Compositions and methods for recombinant antibodies targeting post-translational modifications

Abstract

This application relates to antibodies or combinations of antibodies or antigen¬ binding fragment(s) thereof that comprise a first binding unit that binds to a first epitope of a target protein that harbors a post-translational modification (PTM) and a second binding unit that binds to a second epitope of a target protein that does not harbor the PTM, as well as antibody fusion molecules and multispecific antibodies or antigen-binding fragments thereof that bind to same.

Description

COMPOSITIONS AND METHODS FOR RECOMBINANT ANTIBODIES TARGETING POST-TRANSLATIONAL MODIFICATIONS CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to U.S. Provisional Application No. 63 / 684,165, filedAugust 16, 2024, and U.S. Provisional Application No.63 / 733,094, filed December 12, 2024, the contents of both which are incorporated by reference herein in their entireties. STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH

[0002] This invention was made with government support under R21 CA246457, T32HD007009, R01 GM115945 and R35 GM145373 awarded by the National Institutes of Health. The government has certain rights in the invention. SEQUENCE LISTING

[0003] The instant application contains a Sequence Listing which has been submittedelectronically in XML format and is hereby incorporated by reference in its entirety. Said XML copy, created on August 5, 2025, is named 243735_000436_SL.xml and is 338,176 bytes in size. FIELD OF THE INVENTION

[0004] This application relates to antibodies or combinations of antibodies or antigen-bindingfragment(s) thereof that comprise a first binding unit that binds to a first epitope of a target protein that harbors a post-translational modification (PTM) and a second binding unit that binds to a second epitope of a target protein that does not harbor the PTM, as well as antibody fusion molecules and multispecific antibodies or antigen-binding fragments thereof that bind to same. BACKGROUND

[0005] Post-translational modifications (PTMs) such as methylation, phosphorylation,acetylation, ubiquitination, and glycosylation of proteins play critical roles in regulating manybiological events (1-4), and dysregulation of PTMs in the context of specific protein sequences are observed in diseases, including cancer (5-8). PTMs occur at specific sites within proteins, and each combination of PTM types and modification sites is associated with distinct roles in cellular processes. Accordingly, the identification and quantification of site-specific PTMs are important for the analyses of PTMs. Antibodies targeting site-specific PTMs are essential tools for detecting and enriching PTMs at sites of interest. However, fundamental difficulties in molecular recognition of PTMs, modification sites, and surrounding peptide sequences have hindered the efficient generation of highly sequence-specific anti-PTM antibodies. Many available anti-PTM antibodies, which are commonly generated by animal immunization, have shortcomings (9-13). Furthermore, the widespread use of potentially inconsistent, non- renewable, and molecularly undefined antibodies presents experimental challenges thought to contribute to the reproducibility problem in biomedical research.

[0006] There are two common problems with available antibodies to PTMs. First, many anti-PTM antibodies exhibit low specificity and / or low affinity, leading to cross-reactivity to off- targets or no binding to the intended target (9-13). Second, there is a large lot-to-lot variation of polyclonal antibodies generated by animal immunization. Each polyclonal antibody product is a heterogeneous mixture of antibodies derived from multiple B cells. Thus, each lot (i.e., each immunization product) of a polyclonal antibody is a distinct reagent. Monoclonal antibodies derived from a single B cell should lead to a homogenous antibody (14). Still, hybridoma cells can express multiple different antibody genes or lose the relevant antibody gene over many passages, leading to the lot variability (15, 16). Recombinant antibodies are produced by a defined expression vector, and their amino acid sequences are determined during the characterization process. Their renewability can fundamentally eliminate a major obstacle to reproducibility (12, 17). Indeed, the number of available recombinant antibodies, converted from monoclonal antibodies by cloning genes from hybridoma cells, has increased in the past decade. However, converting sub-optimal monoclonal antibodies into recombinant antibodies itself does not solve the fundamental problem of low-quality anti-PTM antibodies.

[0007] The challenge in generating highly selective antibodies to site-specific PTMs stemsfrom the fundamental, biophysical difficulties in recognizing PTMs. The chemical moieties of PTMs are usually minute, and differences among PTMs (e.g., mono-, di- and trimethylation) are subtle. In addition to specifically recognizing the target PTM, antibodies need to discriminateclosely related sequences surrounding the modification. Furthermore, the PTM sites are usually located in the flexible or disordered regions on proteins (18-20), and thus, unfavorable entropic loss of a flexible peptide segment upon antibody binding hinders achieving high affinity. Previous attempts to generate site-specific anti-PTM antibodies via a standard approach combining library sorting and directed evolution required extensive engineering and iterative optimization to achieve the desired outcomes (12, 21). Consequently, fundamental challenges in molecular recognition hamper identifying high-performance anti-PTM antibodies regardless of the existing antibody-generation methods. SUMMARY OF THE INVENTION

[0008] As specified in the Background section above, there is a great need in the art forhighly selective and high-performance anti-post-translational modification (PTM) antibodies. The present application addresses these and other needs.

[0009] In one aspect, provided herein is an antibody or combination of antibodies or antigen-binding fragment(s) thereof, comprising: (i) a first binding unit (B1) that specifically binds to a first epitope of a target protein, wherein the first epitope includes an amino acid residue harboring one or more of a post- translational modification (PTM); and / or (ii) a second binding unit (B2) that specifically binds to both the first binding unit (B1) and a second epitope of the target protein, wherein the second epitope does not include the PTM.

[0010] In some embodiments, the antibody or combination of antibodies or antigen-bindingfragment(s) thereof comprise: (i) a first binding unit (B1) that specifically binds to a first epitope of a target protein, wherein the first epitope includes an amino acid residue harboring one or more of a post- translational modification (PTM); and (ii) a second binding unit (B2) that specifically binds to both the first binding unit (B1) and a second epitope of the target protein, wherein the second epitope does not include the PTM.

[0011] In some embodiments, the PTM is selected from methylation, phosphorylation,acetylation, ubiquitination, glycosylation, formylation, propinylation, butyrylation, crotonylation,benzoylation, 2-hydroxyisobutyrylation, hydroxybutyrylation, lactylation, malonylation, succinylation, glutarylation, hydroxylation, sumoylation, ufmylation, biotinylation, serotonylation, dopaminylation, isomerization, myristoylation, sulfation, nitrosylation, ADP- ribosylation, prenylation, palmitoylation, deamidation, and proteolytic cleavage.

[0012] In some embodiments, the PTM is methylation or phosphorylation.

[0013] In some embodiments, the PTM is comprised within a flexible, disordered region of thetarget protein that does not form a fixed three-dimensional (3D) structure.

[0014] In some embodiments, the target protein is a histone protein, a platelet-derived growthfactor receptor beta (PDGFRb) protein, a breakpoint cluster region (BCR) protein, a protein tyrosine phosphatase (PTPN11) protein, or a fibroblast growth factor receptor substrate 2 (FRS2) protein.

[0015] In some embodiments, the target protein is a histone protein, or a fragment thereof.

[0016] In some embodiments, the histone protein is a histone H3 protein, or fragment thereof,or a histone H4 protein, or fragment thereof.

[0017] In some embodiments, the histone protein is a histone H3 protein, or fragment thereof.

[0018] In some embodiments, the histone protein is a histone H4 protein, or fragment thereof.

[0019] In some embodiments, the first epitope includes a lysine (K) residue that is methylatedone or more times.

[0020] In some embodiments, the lysine (K) residue is trimethylated.

[0021] In some embodiments, the lysine (K) residue is positioned at amino acid position 9, 27,or 56 of the histone H3 protein, or a fragment thereof.

[0022] In some embodiments, the lysine (K) residue is positioned at amino acid position 20 ofthe histone H4 protein, or a fragment thereof.

[0023] In some embodiments, B1 comprises:a) a heavy chain complementarity determining region 1 (CDR1), a heavy chain CDR2, a heavy chain CDR3 of a heavy chain variable region (VH) comprising the amino acid sequence of SEQ ID NO: 6; and / or a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a light chain variable region (VL) comprising the amino acid sequence of SEQ ID NO: 1; or b) a heavy chain complementarity determining region 1 (CDR1), a heavy chain CDR2, a heavy chain CDR3 of a heavy chain variable region (VH) comprising the amino acidsequence of SEQ ID NO: 6; and / or a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a light chain variable region (VL) comprising the amino acid sequence of SEQ ID NO: 2.

[0024] In some embodiments, B1 comprises a heavy chain CDR1 comprising the amino acidsequence of SEQ ID NO: 7, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 8, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 9.

[0025] In some embodiments, B1 comprises a light chain CDR1 comprising the amino acidsequence of SEQ ID NO: 3, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 4, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 5.

[0026] In some embodiments, B1 comprises a heavy chain CDR1 comprising the amino acidsequence of SEQ ID NO: 7, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 8, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 9; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 3, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 4, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 5.

[0027] In some embodiments, B1 comprises a VH comprising an amino acid sequence of SEQID NO: 6, and a VL comprising an amino acid sequence of SEQ ID NO: 1 or 2.

[0028] In some embodiments, B2 comprises a heavy chain complementarity determiningregion 1 (CDR1), a heavy chain CDR2, a heavy chain CDR3 of a heavy chain variable region (VH) comprising the amino acid sequence of SEQ ID NO: 25, 43, 54, 63, 73, 80, 84, 89, 93, 108, 115, 124, 127, 129, or 131; and / or a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a light chain variable region (VL) comprising the amino acid sequence of SEQ ID NO: 21, 41, 52, 61, 71, 78, 82, 87, 91, 103, 112, 117, or 122.

[0029] In some embodiments, B2 comprises:a) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 25, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 21; b) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 43, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 41;c) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 54, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 52; d) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 63, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 61; e) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 73, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71; f) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 80, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 78; g) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 84, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 82; h) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 89, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 87; i) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 93, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 91; j) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 93, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 103; k) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 93, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71; l) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 108, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71;m) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 93, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 112; n) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 115, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71; o) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 93, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 117; p) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 124, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 122; q) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 127, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 122; r) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 129, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 122; or s) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 131, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 122.

[0030] In some embodiments, B2 comprises:a) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 26, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 28; b) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 46; c) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 26, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 55;d) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 65; e) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 74, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76; f) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76; g) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 74, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 85; h) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76; i) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; j) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; k) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 125; or l) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 132.

[0031] In some embodiments, B2 comprises:a) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 24;b) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 42; c) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 53; d) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 62; e) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; f) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 79; g) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 83; h) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 88; i) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 92; j) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 104; k) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 113;l) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 118; or m) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 123.

[0032] In some embodiments, B2 comprises:a) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 26, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 28; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 24; b) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 46; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 42; c) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 26, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 55; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 53; d) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 65; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 62;e) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 74, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; f) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 79; g) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 74, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 85; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 83; h) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 88; i) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 92;j) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 104; k) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; l) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 113; m) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; n) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 118;o) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 125; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 123; or p) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 132; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 123.

[0033] In some embodiments, B2 comprises a VH comprising an amino acid sequence of SEQID NO: 25, 43, 54, 63, 73, 80, 84, 89, 93, 108, 115, 124, 127, 129, or 131; and / or a VL comprising an amino acid sequence of SEQ ID NO: 21, 41, 52, 61, 71, 78, 82, 87, 91, 103, 112, 117, or 122.

[0034] In some embodiments, B2 comprises:a) a VH comprising an amino acid sequence of SEQ ID NO: 25, and a VL comprising an amino acid sequence of SEQ ID NO: 21; b) a VH comprising an amino acid sequence of SEQ ID NO: 43, and a VL comprising an amino acid sequence of SEQ ID NO: 41; c) a VH comprising an amino acid sequence of SEQ ID NO: 54, and a VL comprising an amino acid sequence of SEQ ID NO: 52; d) a VH comprising an amino acid sequence of SEQ ID NO: 63, and a VL comprising an amino acid sequence of SEQ ID NO: 61; e) a VH comprising an amino acid sequence of SEQ ID NO: 73, and a VL comprising an amino acid sequence of SEQ ID NO: 71; f) a VH comprising an amino acid sequence of SEQ ID NO: 80, and a VL comprising an amino acid sequence of SEQ ID NO: 78; g) a VH comprising an amino acid sequence of SEQ ID NO: 84, and a VL comprising an amino acid sequence of SEQ ID NO: 82;h) a VH comprising an amino acid sequence of SEQ ID NO: 89, and a VL comprising an amino acid sequence of SEQ ID NO: 87; i) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VL comprising an amino acid sequence of SEQ ID NO: 91; j) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VL comprising an amino acid sequence of SEQ ID NO: 103; k) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VL comprising an amino acid sequence of SEQ ID NO: 71; l) a VH comprising an amino acid sequence of SEQ ID NO: 108, and a VL comprising an amino acid sequence of SEQ ID NO: 71; m) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VL comprising an amino acid sequence of SEQ ID NO: 112; n) a VH comprising an amino acid sequence of SEQ ID NO: 115, and a VL comprising an amino acid sequence of SEQ ID NO: 71; o) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VL comprising an amino acid sequence of SEQ ID NO: 117; p) a VH comprising an amino acid sequence of SEQ ID NO: 124, and a VL comprising an amino acid sequence of SEQ ID NO: 122; q) a VH comprising an amino acid sequence of SEQ ID NO: 127, and a VL comprising an amino acid sequence of SEQ ID NO: 122; r) a VH comprising an amino acid sequence of SEQ ID NO: 129, and a VL comprising an amino acid sequence of SEQ ID NO: 122; or s) a VH comprising an amino acid sequence of SEQ ID NO: 131, and a VL comprising an amino acid sequence of SEQ ID NO: 122.

[0035] In some embodiments, (i) B1 specifically binds to a first epitope of a histone H3protein, said first epitope including a lysine (K) residue harboring one or more of a PTM; (ii) B2 specifically binds to both the first binding unit (B1) and to a second epitope of the histone H3 protein, said second epitope not including the PTM; and (iii) the first and the second epitope comprise, or are comprised within, the amino acid sequence selected from (residues harboring PTM in bold text, below): a) ARTKQTARKSTGGKAP (SEQ ID NO: 230);b) QLATKAARKSAPATGG (SEQ ID NO: 231); and c) LREIRRYQKSTELLIR (SEQ ID NO: 233).

[0036] In some embodiments, (i) B1 specifically binds to a first epitope of a histone H4protein, said first epitope including a lysine (K) residue harboring one or more of a PTM; (ii) B2 specifically binds to both the first binding unit (B1) and to a second epitope of the histone H4 protein, said second epitope not including the PTM; and (iii) the first and the second epitope comprise, or are comprised within, the amino acid sequence KGGAKRHRKVLRDNIQ (SEQ ID NO: 235) (residue harboring PTM in bold text).

[0037] In some embodiments, the lysine (K) residue is trimethylated.

[0038] In some embodiments, the histone H3 protein consists of the amino acid sequence ofany one of SEQ ID NOs: 240-247 and the histone H4 protein consists of the amino acid sequence of SEQ ID NO: 248.

[0039] In some embodiments, the target protein is a platelet-derived growth factor receptorbeta (PDGFRb) protein, a breakpoint cluster region (BCR) protein, a protein tyrosine phosphatase (PTPN11) protein, or a fibroblast growth factor receptor substrate 2 (FRS2) protein.

[0040] In some embodiments, the target protein is a platelet-derived growth factor receptorbeta (PDGFRb) protein, or a fragment thereof, or a breakpoint cluster region (BCR) protein, or a fragment thereof.

[0041] In some embodiments, the first epitope includes a tyrosine (Y) residue that isphosphorylated once.

[0042] In some embodiments, the target protein is a platelet-derived growth factor receptorbeta (PDGFRb) protein, or a fragment thereof, and the tyrosine (Y) residue is positioned at amino acid position 716 of the PDGFRb protein, or a fragment thereof.

[0043] In some embodiments, the target protein is a breakpoint cluster region (BCR) protein,or a fragment thereof, and the tyrosine (Y) residue is positioned at amino acid position 177 of the BCR protein, or a fragment thereof.

[0044] In some embodiments, the target protein is a protein tyrosine phosphatase (PTPN11)protein, or a fragment thereof, and the tyrosine (Y) residue is positioned at amino acid position 580 of the PTPN11 protein, or a fragment thereof.

[0045] In some embodiments, the target protein is a fibroblast growth factor receptor substrate2 (FRS2) protein, or a fragment thereof, and the tyrosine (Y) residue is positioned at amino acid position 196 of the FRS2 protein, or a fragment thereof.

[0046] In some embodiments, B1 comprises a heavy chain complementarity determiningregion 1 (CDR1), a heavy chain CDR2, a heavy chain CDR3 of a heavy chain variable region (VH) comprising the amino acid sequence of SEQ ID NO: 138; and / or a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a light chain variable region (VL) comprising the amino acid sequence of SEQ ID NO: 134 or 148.

[0047] In some embodiments, B1 comprises a heavy chain CDR1 comprising the amino acidsequence of SEQ ID NO: 139, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 140, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 141.

[0048] In some embodiments, B1 comprises a light chain CDR1 comprising the amino acidsequence of SEQ ID NO: 135, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 136, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 137.

[0049] In some embodiments, B1 comprises a heavy chain CDR1 comprising the amino acidsequence of SEQ ID NO: 139, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 140, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 141; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 135, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 136, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 137.

[0050] In some embodiments, B1 comprises a VH comprising an amino acid sequence of SEQID NO: 138, and a VL comprising an amino acid sequence of SEQ ID NO: 134 or 148.

[0051] In some embodiments, B2 comprises a heavy chain complementarity determiningregion 1 (CDR1), a heavy chain CDR2, a heavy chain CDR3 of a heavy chain variable region (VH) comprising the amino acid sequence of SEQ ID NO: 144, 152, 156, 162, 167, 173, or 178; and / or a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a light chain variable region (VL) comprising the amino acid sequence of SEQ ID NO: 71, 151, 160, 165, 172, 176, or 180.

[0052] In some embodiments, B2 comprises:a) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 144, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71; b) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 152, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 151; c) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 156, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71; d) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 162, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 160; e) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 167, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 165; f) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 173, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 172; g) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 178, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 176; or h) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 167, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 180.

[0053] In some embodiments, B2 comprises:a) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 145, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 146; b) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 145, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 153;c) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 157, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 146; d) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 157, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 153; or e) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 168, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 169, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 170.

[0054] In some embodiments, B2 comprises:a) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; b) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 161; c) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 166; d) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 177; or e) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 181.

[0055] In some embodiments, B2 comprises:a) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 145, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 146; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising theamino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; b) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 145, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 153; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; c) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 157, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 146; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; d) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 157, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 153; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 161; e) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 168, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 169, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 170; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 166; f) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 168, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 169, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 170; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising theamino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 177; or g) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 168, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 169, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 170; or and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 181.

[0056] In some embodiments, B2 comprises a VH comprising an amino acid sequence of SEQID NO: 144, 152, 156, 162, 167, 173, or 178; and / or a VL comprising an amino acid sequence of SEQ ID NO: 71, 151, 160, 165, 172, 176, or 180.

[0057] In some embodiments, B2 comprises:a) a VH comprising an amino acid sequence of SEQ ID NO: 144, and a VL comprising an amino acid sequence of SEQ ID NO: 71; b) a VH comprising an amino acid sequence of SEQ ID NO: 152, and a VL comprising an amino acid sequence of SEQ ID NO: 151; c) a VH comprising an amino acid sequence of SEQ ID NO: 156, and a VL comprising an amino acid sequence of SEQ ID NO: 71; d) a VH comprising an amino acid sequence of SEQ ID NO: 162, and a VL comprising an amino acid sequence of SEQ ID NO: 160; e) a VH comprising an amino acid sequence of SEQ ID NO: 167, and a VL comprising an amino acid sequence of SEQ ID NO: 165; f) a VH comprising an amino acid sequence of SEQ ID NO: 173, and a VL comprising an amino acid sequence of SEQ ID NO: 172; g) a VH comprising an amino acid sequence of SEQ ID NO: 178, and a VL comprising an amino acid sequence of SEQ ID NO: 176; or h) a VH comprising an amino acid sequence of SEQ ID NO: 167, and a VL comprising an amino acid sequence of SEQ ID NO: 180.

[0058] In some embodiments, (i) B1 specifically binds to a first epitope of a platelet-derivedgrowth factor receptor beta (PDGFRb) protein, said first epitope including a tyrosine (Y) residue harboring one or more of a PTM; (ii) B2 specifically binds to both the first binding unit (B1) andto a second epitope of the PDGFRb protein, said second epitope not including the PTM; and (iii) the first and the second epitope comprise, or are comprised within, the amino acid sequence PSAELYSNALPVG (SEQ ID NO: 236) (residue harboring PTM in bold text).

[0059] In some embodiments, (i) B1 specifically binds to a first epitope of a breakpoint clusterregion (BCR) protein, said first epitope including a tyrosine (Y) residue harboring one or more of a PTM; (ii) B2 specifically binds to both the first binding unit (B1) and a second epitope of the BCR protein, said second epitope not including the PTM; and (iii) the first and the second epitope comprise, or are comprised within, the amino acid sequence AEKPFYVNVEFHH (SEQ ID NO: 237) (residue harboring PTM in bold text).

[0060] In some embodiments, (i) B1 specifically binds to a first epitope of a protein tyrosinephosphatase (PTPN11) protein, said first epitope including a tyrosine (Y) residue harboring one or more of a PTM; (ii) B2 specifically binds to both the first binding unit (B1) and a second epitope of the PTPN11 protein, said second epitope not including the PTM; and (iii) the first and the second epitope comprise, or are comprised within, the amino acid sequence DSARVYENVGLMQ (SEQ ID NO: 238) (residue harboring PTM in bold text).

[0061] In some embodiments, (i) B1 specifically binds to a first epitope of a fibroblast growthfactor receptor substrate 2 (FRS2) protein, said first epitope including a tyrosine (Y) residue harboring one or more of a PTM; (ii) B2 specifically binds to both the first binding unit (B1) and a second epitope of the FRS2 protein, said second epitope not including the PTM; and (iii) the first and the second epitope comprise, or are comprised within, the amino acid sequence EQVHTYVNTTGVQ (SEQ ID NO: 239) (residue harboring PTM in bold text).

[0062] In some embodiments, the tyrosine (Y) residue is phosphorylated once.

[0063] In some embodiments, the platelet-derived growth factor receptor beta (PDGFRb)protein consists of the amino acid sequence of SEQ ID NO: 249, the breakpoint cluster region (BCR) protein consists of the amino acid sequence of SEQ ID NO: 250, the protein tyrosine phosphatase (PTPN11) protein consists of the amino acid sequence of SEQ ID NO: 251, and the fibroblast growth factor receptor substrate 2 (FRS2) protein consists of the amino acid sequence of SEQ ID NO: 252.

[0064] In some embodiments, one or both of B1 and B2 comprise an antibody or an antigen-binding fragment thereof.

[0065] In some embodiments, the antibody or antigen-binding fragment(s) thereof isrecombinant.

[0066] In some embodiments, the antibody or combination of antibodies or antigen-bindingfragment(s) thereof binds to the target protein at a dissociation constant (KD) of about 1x10-7M or less.

[0067] In some embodiments, the antibody or combination of antibodies or antigen-bindingfragment(s) thereof binds to the target protein at a dissociation constant (KD) from about 3.0x10-10to about 1.2x10-8M.

[0068] In some embodiments, the KD is measured using a peptide immunoprecipitation (IP)assay.

[0069] In some embodiments, one or both of B1 and B2 comprise a humanized antibody orantigen-binding fragment thereof, human antibody or antigen-binding fragment thereof, murine antibody or antigen-binding fragment thereof, chimeric antibody or antigen-binding fragment thereof, fragment antigen-binding region (Fab), monovalent Fab', divalent Fab2, F(ab)'3 fragments, single-chain fragment variable (scFv), bis-scFv, (scFv)2, long-neck scFv-Fc, diabody, minibody, nanobody, triabody, tetrabody, disulfide stabilized Fv protein (dsFv), single-domain antibody (sdAb), Ig NAR, single heavy chain antibody, bispecific antibody or biding fragment thereof, bi-specific T-cell engager (BiTE), trispecific antibody, or a derivative thereof.

[0070] In some embodiments, one or both of B1 and B2 comprise a fragment antigen-bindingregion (Fab).

[0071] In some embodiments, one or both of B1 and B2 comprise a single-chain fragmentvariable (scFv).

[0072] In some embodiments, the scFv variable regions are connected by a linker sequence.

[0073] In some embodiments, the linker sequence comprises the amino acid sequenceGILGSGGGGSGGGGSGGGGS (SEQ ID NO: 15) or GILSGSSSSGSSSSGSSSSG (SEQ ID NO: 32).

[0074] In some embodiments, B1 is connected to B2 via a linker sequence.

[0075] In some embodiments, the linker sequence is 10 to 40 amino acids in length.

[0076] In some embodiments, the linker sequence is 15 to 30 amino acids in length.

[0077] In some embodiments, the linker sequence comprises the amino acid sequence(SSSSG)3-SS (SEQ ID NO: 31), (SSSSG)4-SS (SEQ ID NO: 34), or (SSSSG)5-SS (SEQ ID NO: 35).

[0078] In some embodiments, one or both of B1 and B2 comprise an IgG antibody.

[0079] In some embodiments, the IgG antibody is of IgG1, IgG2, IgG3, or IgG4 subclass.

[0080] In some embodiments, the IgG antibody is of IgG1 subclass.

[0081] In some embodiments, the IgG1 antibody comprises one or more of an Fc domain.

[0082] In some embodiments, the IgG1 antibody or antigen-binding fragment comprises aS239C mutation in the Fc domain(s).

[0083] In some embodiments, the IgG1 antibody or antigen-binding fragment comprisesT252M and / or T254S mutations in the Fc domain(s).

[0084] In some embodiments, the antibody or combination of antibodies or antigen-bindingfragment(s) thereof comprise two Fc domains that dimerize to form an Fc heterodimer.

[0085] In some embodiments, the Fc domains in the Fc heterodimer comprise knob-in-holemutations as compared to a wild-type Fc domain.

[0086] In some embodiments, one Fc domain in the Fc heterodimer comprises amino acidsubstitutions P354C and T366W (according to EU numbering) as compared to a wild-type Fc domain, and the other Fc domain in the Fc heterodimer comprises amino acid substitutions Y349C, T366S, M368A, and Y407V (according to EU numbering) as compared to a wild-type Fc domain.

[0087] In some embodiments, one or both of B1 and B2 are connected to the Fc domain via alinker sequence.

[0088] In some embodiments, the linker sequence is 10 to 40 amino acids in length.

[0089] In some embodiments, the linker sequence is 15 to 30 amino acids in length.

[0090] In some embodiments, the linker sequence comprises the amino acid sequenceSSLERSSSSSGSSSSGSSGRS (SEQ ID NO: 16), RTVLSSLERSSSSSGSSSSGSSGRS (SEQ ID NO: 142), or RTVSLERSSSSSGSSSSGSSGRS (SEQ ID NO: 100).

[0091] In some embodiments, a hinge sequence separates the linker sequence and the Fcdomain(s).

[0092] In some embodiments, the hinge sequence comprises the amino acid sequenceGCKPCICT (SEQ ID NO: 17).

[0093] In some embodiments, one of the Fc domains that form the Fc heterodimer comprisesthe amino acid sequence of SEQ ID NO: 187, and the other of the Fc domains that form the Fc heterodimer comprises the amino acid sequence of SEQ ID NO: 188.

[0094] In some embodiments, one or both of B1 and B2 are attached to a solid support or a cellsurface.

[0095] In some embodiments, the solid support is a bead, a membrane, a plate, a tube, acolumn, a biosensor chip, or Sepharose.

[0096] In some embodiments, one or both of B1 and B2 are attached to the solid support usingan affinity binding pair.

[0097] In some embodiments, one member of the affinity binding pair comprises a biotinmoiety, and the other member of the affinity binding pair comprises a streptavidin moiety.

[0098] In some embodiments, one or both of B1 and B2 are attached to the cell surface usingan anchoring protein.

[0099] In some embodiments, the anchoring protein is Aga2 anchoring protein.

[0100] In some embodiments, the Aga2 anchoring protein comprises the amino acid sequenceMQLLRCFSIFSVIASVLAQELTTICEQIPSPTLESTPYSLSTTTILANGKAMQGVFEYYKSV TFVSNCGSHPSTTSKGSPINTQYVF (SEQ ID NO: 29).

[0101] In some embodiments, the cell is a yeast cell.

[0102] In some embodiments, the first or second member of the affinity binding pair, or theanchoring protein, is connected to one or both of B1 and B2 via a linker sequence.

[0103] In some embodiments, the antibody or combination of antibodies or antigen-bindingfragment(s) thereof further comprise one or more of a reporter protein or a protein tag.

[0104] In some embodiments, the protein tag is an affinity tag

[0105] In some embodiments, the reporter protein or the protein tag is a V5 epitope tag (V5-tag), an biotinylation tag, a polyhistidine tag (His-tag), a fluorescent protein, a c-myc tag, a glutathione S-transferase (GST) tag, a FLAG tag, an HA tag, an S-tag, a FLASH tag, a SNAP- tag, a streptavidin moiety, a Strep II tag, an HA tag, an L14 tag, a 4C-RGD tag, an LH tag, a protein A, a maltose-binding protein (MBP), an albumin-binding protein, a chitin binding domain, a calmodulin binding peptide, a cellulose binding domain, a biotin moiety, an oligonucleotide (oligo), or a horseradish peroxidase (HRP).

[0106] In some embodiments, the reporter protein or the protein tag is a V5 epitope tag (V5-tag), a biotinylation tag, or a polyhistidine tag (His-tag).

[0107] In some embodiments, the V5-tag comprises the amino acid sequenceGKPIPNPLLGLDST (SEQ ID NO: 33).

[0108] In some embodiments, the His-tag comprises the amino acid sequence HHHHHH (SEQID NO: 99).

[0109] In some embodiments, the biotinylation tag is Avitag.

[0110] In some embodiments, the Avitag comprises the amino acid sequenceGLNDIFEAQKIEWHE (SEQ ID NO: 14).

[0111] Also provided herein is an antibody fusion molecule, comprising:a) a first binding unit (B1), comprising: (i) a first heavy chain region of a first Fab (“Fab1”); (ii) a first light chain that pairs with the first heavy chain region to form Fab1, wherein Fab1 comprises a first antigen-binding domain (“ABD1”) that specifically binds to a first epitope of a target protein, wherein the first epitope includes an amino acid residue harboring one or more of a post-translational modification (PTM); and b) a second binding unit (B2), comprising: (i) a second heavy chain region of a second Fab (“Fab2”) (ii) a second light chain that pairs with the second heavy chain region to form Fab2, wherein Fab2 comprises a second antigen-binding domain (“ABD2”) that specifically binds to both the first binding unit (B1) and a second epitope of the target protein, wherein the second epitope does not include the PTM; and wherein each of Fab1 and Fab2 are connected to a biotinylation tag comprising a biotin moiety via a linker sequence, wherein the biotin moiety forms a first member of an affinity binding pair.

[0112] In some embodiments, the first member of the affinity binding pair is non-covalentlyattached to a second member of the affinity binding pair, said second member comprising a streptavidin moiety.

[0113] In some embodiments, the second member of the affinity binding pair is immobilizedon a solid support.

[0114] In some embodiments, the solid support is a bead, a membrane, a plate, a tube, acolumn, a biosensor chip, or Sepharose.

[0115] In some embodiments, the PTM is selected from methylation, phosphorylation,acetylation, ubiquitination, glycosylation, formylation, propinylation, butyrylation, crotonylation, benzoylation, 2-hydroxyisobutyrylation, hydroxybutyrylation, lactylation, malonylation, succinylation, glutarylation, hydroxylation, sumoylation, ufmylation, biotinylation, serotonylation, dopaminylation, isomerization, myristoylation, sulfation, nitrosylation, ADP- ribosylation, prenylation, palmitoylation, deamidation, and proteolytic cleavage.

[0116] In some embodiments, the PTM is methylation or phosphorylation.

[0117] In some embodiments, the PTM is comprised within a flexible, disordered region of thetarget protein that does not form a fixed three-dimensional (3D) structure.

[0118] In some embodiments, the target protein is a histone protein, a platelet-derived growthfactor receptor beta (PDGFRb) protein, a breakpoint cluster region (BCR) protein, a protein tyrosine phosphatase (PTPN11) protein, or a fibroblast growth factor receptor substrate 2 (FRS2) protein.

[0119] In some embodiments, the target protein is a histone protein, or a fragment thereof.

[0120] In some embodiments, the histone protein is a histone H3 protein, or fragment thereof,or a histone H4 protein, or fragment thereof.

[0121] In some embodiments, the histone protein is a histone H3 protein, or fragment thereof.

[0122] In some embodiments, the histone protein is a histone H4 protein, or fragment thereof.

[0123] In some embodiments, the first epitope includes a lysine (K) residue that is methylatedone or more times.

[0124] In some embodiments, the lysine (K) residue is trimethylated.

[0125] In some embodiments, the lysine (K) residue is positioned at amino acid position 9, 27,or 56 of the histone H3 protein, or a fragment thereof.

[0126] In some embodiments, the lysine (K) residue is positioned at amino acid position 20 ofthe histone H4 protein, or a fragment thereof.

[0127] In some embodiments, B1 comprises:a) a heavy chain complementarity determining region 1 (CDR1), a heavy chain CDR2, a heavy chain CDR3 of a heavy chain variable region (VH) comprising the amino acid sequence of SEQ ID NO: 6; and / or a light chain CDR1, a light chain CDR2, and a light chainCDR3 of a light chain variable region (VL) comprising the amino acid sequence of SEQ ID NO: 1; or b) a heavy chain complementarity determining region 1 (CDR1), a heavy chain CDR2, a heavy chain CDR3 of a heavy chain variable region (VH) comprising the amino acid sequence of SEQ ID NO: 6; and / or a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a light chain variable region (VL) comprising the amino acid sequence of SEQ ID NO: 2.

[0128] In some embodiments, B1 comprises a heavy chain CDR1 comprising the amino acidsequence of SEQ ID NO: 7, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 8, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 9.

[0129] In some embodiments, B1 comprises a light chain CDR1 comprising the amino acidsequence of SEQ ID NO: 3, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 4, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 5.

[0130] In some embodiments, B1 comprises a heavy chain CDR1 comprising the amino acidsequence of SEQ ID NO: 7, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 8, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 9; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 3, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 4, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 5.

[0131] In some embodiments, B1 comprises a VH comprising an amino acid sequence of SEQID NO: 6, and a VL comprising an amino acid sequence of SEQ ID NO: 1 or 2.

[0132] In some embodiments, B2 comprises a heavy chain complementarity determiningregion 1 (CDR1), a heavy chain CDR2, a heavy chain CDR3 of a heavy chain variable region (VH) comprising the amino acid sequence of SEQ ID NO: 25, 43, 54, 63, 73, 80, 84, 89, 93, 108, 115, 124, 127, 129, or 131; and / or a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a light chain variable region (VL) comprising the amino acid sequence of SEQ ID NO: 21, 41, 52, 61, 71, 78, 82, 87, 91, 103, 112, 117, or 122.

[0133] In some embodiments, B2 comprises:a) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 25, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 21;b) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 43, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 41; c) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 54, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 52; d) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 63, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 61; e) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 73, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71; f) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 80, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 78; g) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 84, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 82; h) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 89, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 87; i) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 93, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 91; j) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 93, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 103; k) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 93, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71;l) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 108, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71; m) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 93, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 112; n) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 115, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71; o) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 93, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 117; p) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 124, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 122; q) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 127, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 122; r) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 129, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 122; or s) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 131, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 122.

[0134] In some embodiments, B2 comprises:a) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 26, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 28; b) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 46;c) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 26, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 55; d) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 65; e) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 74, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76; f) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76; g) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 74, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 85; h) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76; i) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; j) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; k) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 125; or l) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 132.

[0135] In some embodiments, B2 comprises:a) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 24; b) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 42; c) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 53; d) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 62; e) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; f) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 79; g) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 83; h) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 88; i) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 92; j) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 104;k) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 113; l) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 118; or m) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 123.

[0136] In some embodiments, B2 comprises:a) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 26, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 28; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 24; b) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 46; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 42; c) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 26, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 55; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 53; d) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 65; and a light chain CDR1comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 62; e) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 74, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; f) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 79; g) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 74, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 85; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 83; h) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 88; i) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising theamino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 92; j) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 104; k) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; l) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 113; m) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; n) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising theamino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 118; o) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 125; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 123; or p) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 132; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 123.

[0137] In some embodiments, B2 comprises:a) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 26, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 28; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 24; b) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 46; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 42; c) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 26, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 55; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising theamino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 53; d) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 65; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 62; e) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 92; f) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; or g) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 118.

[0138] In some embodiments, B2 comprises a VH comprising an amino acid sequence of SEQID NO: 25, 43, 54, 63, 73, 80, 84, 89, 93, 108, 115, 124, 127, 129, or 131; and / or a VL comprising an amino acid sequence of SEQ ID NO: 21, 41, 52, 61, 71, 78, 82, 87, 91, 103, 112, 117, or 122.

[0139] In some embodiments, B2 comprises a VH comprising an amino acid sequence of SEQID NO: 25, 43, 54, 63, 93, or 108; and / or a VL comprising an amino acid sequence of SEQ ID NO: 21, 41, 52, 61, 71, 91, or 117.

[0140] In some embodiments, B2 comprises:a) a VH comprising an amino acid sequence of SEQ ID NO: 25, and a VL comprising an amino acid sequence of SEQ ID NO: 21; b) a VH comprising an amino acid sequence of SEQ ID NO: 43, and a VL comprising an amino acid sequence of SEQ ID NO: 41; c) a VH comprising an amino acid sequence of SEQ ID NO: 54, and a VL comprising an amino acid sequence of SEQ ID NO: 52; d) a VH comprising an amino acid sequence of SEQ ID NO: 63, and a VL comprising an amino acid sequence of SEQ ID NO: 61; e) a VH comprising an amino acid sequence of SEQ ID NO: 73, and a VL comprising an amino acid sequence of SEQ ID NO: 71; f) a VH comprising an amino acid sequence of SEQ ID NO: 80, and a VL comprising an amino acid sequence of SEQ ID NO: 78; g) a VH comprising an amino acid sequence of SEQ ID NO: 84, and a VL comprising an amino acid sequence of SEQ ID NO: 82; h) a VH comprising an amino acid sequence of SEQ ID NO: 89, and a VL comprising an amino acid sequence of SEQ ID NO: 87; i) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VL comprising an amino acid sequence of SEQ ID NO: 91; j) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VL comprising an amino acid sequence of SEQ ID NO: 103; k) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VL comprising an amino acid sequence of SEQ ID NO: 71; l) a VH comprising an amino acid sequence of SEQ ID NO: 108, and a VL comprising an amino acid sequence of SEQ ID NO: 71; m) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VL comprising an amino acid sequence of SEQ ID NO: 112;n) a VH comprising an amino acid sequence of SEQ ID NO: 115, and a VL comprising an amino acid sequence of SEQ ID NO: 71; o) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VL comprising an amino acid sequence of SEQ ID NO: 117; p) a VH comprising an amino acid sequence of SEQ ID NO: 124, and a VL comprising an amino acid sequence of SEQ ID NO: 122; q) a VH comprising an amino acid sequence of SEQ ID NO: 127, and a VL comprising an amino acid sequence of SEQ ID NO: 122; r) a VH comprising an amino acid sequence of SEQ ID NO: 129, and a VL comprising an amino acid sequence of SEQ ID NO: 122; or s) a VH comprising an amino acid sequence of SEQ ID NO: 131, and a VL comprising an amino acid sequence of SEQ ID NO: 122.

[0141] In some embodiments, B2 comprises:a) a VH comprising an amino acid sequence of SEQ ID NO: 25, and a VL comprising an amino acid sequence of SEQ ID NO: 21; b) a VH comprising an amino acid sequence of SEQ ID NO: 43, and a VL comprising an amino acid sequence of SEQ ID NO: 41; c) a VH comprising an amino acid sequence of SEQ ID NO: 54, and a VL comprising an amino acid sequence of SEQ ID NO: 52; d) a VH comprising an amino acid sequence of SEQ ID NO: 63, and a VL comprising an amino acid sequence of SEQ ID NO: 61; e) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VL comprising an amino acid sequence of SEQ ID NO: 91; f) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VL comprising an amino acid sequence of SEQ ID NO: 71; g) a VH comprising an amino acid sequence of SEQ ID NO: 108, and a VL comprising an amino acid sequence of SEQ ID NO: 71; or h) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VL comprising an amino acid sequence of SEQ ID NO: 117.

[0142] In some embodiments, the histone H3 protein consists of the amino acid sequence ofany one of SEQ ID NOs: 240-247 and the histone H4 protein consists of the amino acid sequence of SEQ ID NO: 248.

[0143] In some embodiments, the target protein is a platelet-derived growth factor receptorbeta (PDGFRb) protein, a breakpoint cluster region (BCR) protein, a protein tyrosine phosphatase (PTPN11) protein, or a fibroblast growth factor receptor substrate 2 (FRS2) protein.

[0144] In some embodiments, the target protein is a platelet-derived growth factor receptorbeta (PDGFRb) protein, or a fragment thereof, or a breakpoint cluster region (BCR) protein, or a fragment thereof.

[0145] In some embodiments, the first epitope includes a tyrosine (Y) residue that isphosphorylated once.

[0146] In some embodiments, the target protein is a platelet-derived growth factor receptorbeta (PDGFRb) protein, or a fragment thereof, and the tyrosine (Y) residue is positioned at amino acid position 716 of the PDGFRb protein, or a fragment thereof.

[0147] In some embodiments, the target protein is a breakpoint cluster region (BCR) protein,or a fragment thereof, and the tyrosine (Y) residue is positioned at amino acid position 177 of the BCR protein, or a fragment thereof.

[0148] In some embodiments, the target protein is a protein tyrosine phosphatase (PTPN11)protein, or a fragment thereof, and the tyrosine (Y) residue is positioned at amino acid position 580 of the PTPN11 protein, or a fragment thereof.

[0149] In some embodiments, the target protein is a fibroblast growth factor receptor substrate2 (FRS2) protein, or a fragment thereof, and the tyrosine (Y) residue is positioned at amino acid position 196 of the FRS2 protein, or a fragment thereof.

[0150] In some embodiments, B1 comprises a heavy chain complementarity determiningregion 1 (CDR1), a heavy chain CDR2, a heavy chain CDR3 of a heavy chain variable region (VH) comprising the amino acid sequence of SEQ ID NO: 138; and / or a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a light chain variable region (VL) comprising the amino acid sequence of SEQ ID NO: 134 or 148.

[0151] In some embodiments, B1 comprises a heavy chain CDR1 comprising the amino acidsequence of SEQ ID NO: 139, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 140, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 141.

[0152] In some embodiments, B1 comprises a light chain CDR1 comprising the amino acidsequence of SEQ ID NO: 135, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 136, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 137.

[0153] In some embodiments, B1 comprises a heavy chain CDR1 comprising the amino acidsequence of SEQ ID NO: 139, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 140, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 141; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 135, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 136, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 137.

[0154] In some embodiments, B1 comprises a VH comprising an amino acid sequence of SEQID NO: 138, and a VL comprising an amino acid sequence of SEQ ID NO: 134 or 148.

[0155] In some embodiments, B2 comprises a heavy chain complementarity determiningregion 1 (CDR1), a heavy chain CDR2, a heavy chain CDR3 of a heavy chain variable region (VH) comprising the amino acid sequence of SEQ ID NO: 144, 152, 156, 162, 167, 173, or 178; and / or a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a light chain variable region (VL) comprising the amino acid sequence of SEQ ID NO: 71, 151, 160, 165, 172, 176, or 180.

[0156] In some embodiments, B2 comprises:a) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 144, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71; b) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 152, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 151; c) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 156, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71; d) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 162, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 160;e) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 167, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 165; f) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 173, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 172; g) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 178, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 176; or h) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 167, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 180.

[0157] In some embodiments, B2 comprises:a) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 145, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 146; b) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 145, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 153; c) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 157, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 146; d) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 157, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 153; or e) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 168, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 169, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 170.

[0158] In some embodiments, B2 comprises:a) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; b) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 161; c) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 166; d) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 177; or e) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 181.

[0159] In some embodiments, B2 comprises:a) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 145, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 146; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; b) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 145, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 153; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; c) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 157, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 146; and a light chain CDR1comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; d) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 157, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 153; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 161; e) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 168, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 169, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 170; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 166; f) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 168, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 169, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 170; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 177; or g) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 168, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 169, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 170; or and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 181.

[0160] In some embodiments, B2 comprises a VH comprising an amino acid sequence of SEQID NO: 144, 152, 156, 162, 167, 173, or 178; and / or a VL comprising an amino acid sequence of SEQ ID NO: 71, 151, 160, 165, 172, 176, or 180.

[0161] In some embodiments, B2 comprises:a) a VH comprising an amino acid sequence of SEQ ID NO: 144, and a VL comprising an amino acid sequence of SEQ ID NO: 71; b) a VH comprising an amino acid sequence of SEQ ID NO: 152, and a VL comprising an amino acid sequence of SEQ ID NO: 151; c) a VH comprising an amino acid sequence of SEQ ID NO: 156, and a VL comprising an amino acid sequence of SEQ ID NO: 71; d) a VH comprising an amino acid sequence of SEQ ID NO: 162, and a VL comprising an amino acid sequence of SEQ ID NO: 160; e) a VH comprising an amino acid sequence of SEQ ID NO: 167, and a VL comprising an amino acid sequence of SEQ ID NO: 165; f) a VH comprising an amino acid sequence of SEQ ID NO: 173, and a VL comprising an amino acid sequence of SEQ ID NO: 172; g) a VH comprising an amino acid sequence of SEQ ID NO: 178, and a VL comprising an amino acid sequence of SEQ ID NO: 176; or h) a VH comprising an amino acid sequence of SEQ ID NO: 167, and a VL comprising an amino acid sequence of SEQ ID NO: 180.

[0162] In some embodiments, the platelet-derived growth factor receptor beta (PDGFRb)protein consists of the amino acid sequence of SEQ ID NO: 249, the breakpoint cluster region (BCR) protein consists of the amino acid sequence of SEQ ID NO: 250, the protein tyrosine phosphatase (PTPN11) protein consists of the amino acid sequence of SEQ ID NO: 251, and the fibroblast growth factor receptor substrate 2 (FRS2) protein consists of the amino acid sequence of SEQ ID NO: 252.

[0163] In some embodiments, Fab1 is formed by a first heavy chain region comprising anamino acid sequence of SEQ ID NO: 257, or an amino acid sequence having at least 75% identity thereto, and a first light chain comprising an amino acid sequence of SEQ ID NO: 18, or an amino acid sequence having at least 75% identity thereto.

[0164] In some embodiments, Fab2 is formed bya) a second heavy chain region comprising an amino acid sequence of SEQ ID NO: 258, or an amino acid sequence having at least 75% identity thereto, and a second light chain comprising an amino acid sequence of SEQ ID NO: 36, or an amino acid sequence having at least 75% identity thereto;b) a second heavy chain region comprising an amino acid sequence of SEQ ID NO: 259, or an amino acid sequence having at least 75% identity thereto, and a second light chain comprising an amino acid sequence of SEQ ID NO: 47, or an amino acid sequence having at least 75% identity thereto; c) a second heavy chain region comprising an amino acid sequence of SEQ ID NO: 260, or an amino acid sequence having at least 75% identity thereto, and a second light chain comprising an amino acid sequence of SEQ ID NO: 56, or an amino acid sequence having at least 75% identity thereto; d) a second heavy chain region comprising an amino acid sequence of SEQ ID NO: 261, or an amino acid sequence having at least 75% identity thereto, and a second light chain comprising an amino acid sequence of SEQ ID NO: 66, or an amino acid sequence having at least 75% identity thereto; e) a second heavy chain region comprising an amino acid sequence of SEQ ID NO: 262, or an amino acid sequence having at least 75% identity thereto, and a second light chain comprising an amino acid sequence of SEQ ID NO: 97, or an amino acid sequence having at least 75% identity thereto; f) a second heavy chain region comprising an amino acid sequence of SEQ ID NO: 262, or an amino acid sequence having at least 75% identity thereto, and a second light chain comprising an amino acid sequence of SEQ ID NO: 107, or an amino acid sequence having at least 75% identity thereto; g) a second heavy chain region comprising an amino acid sequence of SEQ ID NO: 263, or an amino acid sequence having at least 75% identity thereto, and a second light chain comprising an amino acid sequence of SEQ ID NO: 107, or an amino acid sequence having at least 75% identity thereto; or h) a second heavy chain region comprising an amino acid sequence of SEQ ID NO: 262, or an amino acid sequence having at least 75% identity thereto, and a second light chain comprising an amino acid sequence of SEQ ID NO: 120, or an amino acid sequence having at least 75% identity thereto.

[0165] In some embodiments, the linker is selected from Gn (SEQ ID NO: 253, where n is anyinteger, e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10); GnS (SEQ ID NO: 254, where n is any integer, e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10), SGn (SEQ ID NO: 255, where n is any integer, e.g., 1, 2, 3, 4, 5, 6, or7, 8, 9 or 10), and (GGGGS)n (SEQ ID NO: 256, where n is any integer, e.g., 1, 2, 3, 4, 5, 6, or 7, 8, 9 or 10), (SSSSG)3-SS (SEQ ID NO: 31), (SSSSG)4-SS (SEQ ID NO: 34), and (SSSSG)5- SS (SEQ ID NO: 35).

[0166] In some embodiments, the biotinylation tag is Avitag.

[0167] In some embodiments, the Avitag comprises the amino acid sequenceGLNDIFEAQKIEWHE (SEQ ID NO: 14).

[0168] In some aspects, provided herein is an antibody fusion molecule, comprising:a) a first binding unit (B1) comprising a first scFv, said first scFv comprising a first antigen-binding domain (“ABD1”) that specifically binds to a first epitope of a target protein, wherein the first epitope includes an amino acid residue harboring one or more of a post- translational modification (PTM); and b) a second binding unit (B2) comprising a second scFv, said second scFv comprising a second antigen-binding domain (“ABD2”) that specifically binds to both the first binding unit (B1) and a second epitope of the target protein, wherein the second epitope does not include the PTM; wherein: (i) the variable regions of the first scFv are connected by a first linker sequence and the variable regions of the second scFv are connected by a second linker sequence; (ii) the first scFv is connected to the second scFv via a third linker sequence, said third linker sequence being 10 to 40 amino acids in length; and (iii) wherein either the first scFv or the second scFv is further connected to an anchoring protein via a fourth linker sequence, said anchoring protein being capable of attaching to a cell surface.

[0169] In some embodiments, the PTM is selected from methylation, phosphorylation,acetylation, ubiquitination, glycosylation, formylation, propinylation, butyrylation, crotonylation, benzoylation, 2-hydroxyisobutyrylation, hydroxybutyrylation, lactylation, malonylation, succinylation, glutarylation, hydroxylation, sumoylation, ufmylation, biotinylation, serotonylation, dopaminylation, isomerization, myristoylation, sulfation, nitrosylation, ADP- ribosylation, prenylation, palmitoylation, deamidation, and proteolytic cleavage.

[0170] In some embodiments, the PTM is methylation or phosphorylation.

[0171] In some embodiments, the PTM is comprised within a flexible, disordered region of thetarget protein that does not form a fixed three-dimensional (3D) structure.

[0172] In some embodiments, the target protein is a histone protein, a platelet-derived growthfactor receptor beta (PDGFRb) protein, a breakpoint cluster region (BCR) protein, a protein tyrosine phosphatase (PTPN11) protein, or a fibroblast growth factor receptor substrate 2 (FRS2) protein.

[0173] In some embodiments, the target protein is a histone protein, or a fragment thereof.

[0174] In some embodiments, the histone protein is a histone H3 protein, or fragment thereof,or a histone H4 protein, or fragment thereof.

[0175] In some embodiments, the histone protein is a histone H3 protein, or fragment thereof.

[0176] In some embodiments, the histone protein is a histone H4 protein, or fragment thereof.

[0177] In some embodiments, the first epitope includes a lysine (K) residue that is methylatedone or more times.

[0178] In some embodiments, the lysine (K) residue is trimethylated.

[0179] In some embodiments, the lysine (K) residue is positioned at amino acid position 9, 27,or 56 of the histone H3 protein, or a fragment thereof.

[0180] In some embodiments, the lysine (K) residue is positioned at amino acid position 20 ofthe histone H4 protein, or a fragment thereof.

[0181] In some embodiments, B1 comprises:a) a heavy chain complementarity determining region 1 (CDR1), a heavy chain CDR2, a heavy chain CDR3 of a heavy chain variable region (VH) comprising the amino acid sequence of SEQ ID NO: 6; and / or a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a light chain variable region (VL) comprising the amino acid sequence of SEQ ID NO: 1; or b) a heavy chain complementarity determining region 1 (CDR1), a heavy chain CDR2, a heavy chain CDR3 of a heavy chain variable region (VH) comprising the amino acid sequence of SEQ ID NO: 6; and / or a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a light chain variable region (VL) comprising the amino acid sequence of SEQ ID NO: 2.

[0182] In some embodiments, B1 comprises a heavy chain CDR1 comprising the amino acidsequence of SEQ ID NO: 7, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 8, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 9.

[0183] In some embodiments, B1 comprises a light chain CDR1 comprising the amino acidsequence of SEQ ID NO: 3, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 4, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 5.

[0184] In some embodiments, B1 comprises a heavy chain CDR1 comprising the amino acidsequence of SEQ ID NO: 7, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 8, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 9; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 3, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 4, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 5.

[0185] In some embodiments, B1 comprises a VH comprising an amino acid sequence of SEQID NO: 6, and a VL comprising an amino acid sequence of SEQ ID NO: 1 or 2.

[0186] In some embodiments, B2 comprises a heavy chain complementarity determiningregion 1 (CDR1), a heavy chain CDR2, a heavy chain CDR3 of a heavy chain variable region (VH) comprising the amino acid sequence of SEQ ID NO: 25, 43, 54, 63, 73, 80, 84, 89, 93, 108, 115, 124, 127, 129, or 131; and / or a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a light chain variable region (VL) comprising the amino acid sequence of SEQ ID NO: 21, 41, 52, 61, 71, 78, 82, 87, 91, 103, 112, 117, or 122.

[0187] In some embodiments, B2 comprises:a) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 25, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 21; b) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 43, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 41; c) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 54, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 52;d) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 63, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 61; e) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 73, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71; f) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 80, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 78; g) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 84, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 82; h) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 89, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 87; i) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 93, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 91; j) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 93, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 103; k) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 93, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71; l) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 108, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71; m) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 93, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 112;n) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 115, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71; o) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 93, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 117; p) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 124, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 122; q) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 127, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 122; r) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 129, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 122; or s) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 131, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 122.

[0188] In some embodiments, B2 comprises:a) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 26, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 28; b) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 46; c) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 26, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 55; d) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 65;e) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 74, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76; f) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76; g) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 74, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 85; h) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76; i) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; j) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; k) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 125; or l) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 132.

[0189] In some embodiments, B2 comprises:a) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 24; b) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 42;c) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 53; d) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 62; e) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; f) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 79; g) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 83; h) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 88; i) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 92; j) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 104; k) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 113; l) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 118; orm) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 123.

[0190] In some embodiments, B2 comprises:a) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 26, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 28; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 24; b) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 46; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 42; c) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 26, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 55; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 53; d) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 65; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 62; e) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 74, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76; and a light chain CDR1comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; f) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 79; g) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 74, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 85; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 83; h) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 88; i) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 92; j) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising theamino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 104; k) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; l) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 113; m) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; n) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 118; o) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 125; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising theamino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 123; or p) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 132; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 123.

[0191] In some embodiments, B2 comprises a VH comprising an amino acid sequence of SEQID NO: 25, 43, 54, 63, 73, 80, 84, 89, 93, 108, 115, 124, 127, 129, or 131; and / or a VL comprising an amino acid sequence of SEQ ID NO: 21, 41, 52, 61, 71, 78, 82, 87, 91, 103, 112, 117, or 122.

[0192] In some embodiments, B2 comprises:a) a VH comprising an amino acid sequence of SEQ ID NO: 25, and a VL comprising an amino acid sequence of SEQ ID NO: 21; b) a VH comprising an amino acid sequence of SEQ ID NO: 43, and a VL comprising an amino acid sequence of SEQ ID NO: 41; c) a VH comprising an amino acid sequence of SEQ ID NO: 54, and a VL comprising an amino acid sequence of SEQ ID NO: 52; d) a VH comprising an amino acid sequence of SEQ ID NO: 63, and a VL comprising an amino acid sequence of SEQ ID NO: 61; e) a VH comprising an amino acid sequence of SEQ ID NO: 73, and a VL comprising an amino acid sequence of SEQ ID NO: 71; f) a VH comprising an amino acid sequence of SEQ ID NO: 80, and a VL comprising an amino acid sequence of SEQ ID NO: 78; g) a VH comprising an amino acid sequence of SEQ ID NO: 84, and a VL comprising an amino acid sequence of SEQ ID NO: 82; h) a VH comprising an amino acid sequence of SEQ ID NO: 89, and a VL comprising an amino acid sequence of SEQ ID NO: 87; i) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VL comprising an amino acid sequence of SEQ ID NO: 91;j) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VL comprising an amino acid sequence of SEQ ID NO: 103; k) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VL comprising an amino acid sequence of SEQ ID NO: 71; l) a VH comprising an amino acid sequence of SEQ ID NO: 108, and a VL comprising an amino acid sequence of SEQ ID NO: 71; m) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VL comprising an amino acid sequence of SEQ ID NO: 112; n) a VH comprising an amino acid sequence of SEQ ID NO: 115, and a VL comprising an amino acid sequence of SEQ ID NO: 71; o) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VL comprising an amino acid sequence of SEQ ID NO: 117; p) a VH comprising an amino acid sequence of SEQ ID NO: 124, and a VL comprising an amino acid sequence of SEQ ID NO: 122; q) a VH comprising an amino acid sequence of SEQ ID NO: 127, and a VL comprising an amino acid sequence of SEQ ID NO: 122; r) a VH comprising an amino acid sequence of SEQ ID NO: 129, and a VL comprising an amino acid sequence of SEQ ID NO: 122; or s) a VH comprising an amino acid sequence of SEQ ID NO: 131, and a VL comprising an amino acid sequence of SEQ ID NO: 122.

[0193] In some embodiments, the histone H3 protein consists of the amino acid sequence ofany one of SEQ ID NOs: 240-247 and the histone H4 protein consists of the amino acid sequence of SEQ ID NO: 248.

[0194] In some embodiments, the target protein is a platelet-derived growth factor receptorbeta (PDGFRb) protein, a breakpoint cluster region (BCR) protein, a protein tyrosine phosphatase (PTPN11) protein, or a fibroblast growth factor receptor substrate 2 (FRS2) protein.

[0195] In some embodiments, the target protein is a platelet-derived growth factor receptorbeta (PDGFRb) protein, or a fragment thereof, or a breakpoint cluster region (BCR) protein, or a fragment thereof.

[0196] In some embodiments, the first epitope includes a tyrosine (Y) residue that isphosphorylated once.

[0197] In some embodiments, the target protein is a platelet-derived growth factor receptorbeta (PDGFRb) protein, or a fragment thereof, and the tyrosine (Y) residue is positioned at amino acid position 716 of the PDGFRb protein, or a fragment thereof.

[0198] In some embodiments, the target protein is a breakpoint cluster region (BCR) protein,or a fragment thereof, and the tyrosine (Y) residue is positioned at amino acid position 177 of the BCR protein, or a fragment thereof.

[0199] In some embodiments, the target protein is a protein tyrosine phosphatase (PTPN11)protein, or a fragment thereof, and the tyrosine (Y) residue is positioned at amino acid position 580 of the PTPN11 protein, or a fragment thereof.

[0200] In some embodiments, the target protein is a fibroblast growth factor receptor substrate2 (FRS2) protein, or a fragment thereof, and the tyrosine (Y) residue is positioned at amino acid position 196 of the FRS2 protein, or a fragment thereof.

[0201] In some embodiments, B1 comprises a heavy chain complementarity determiningregion 1 (CDR1), a heavy chain CDR2, a heavy chain CDR3 of a heavy chain variable region (VH) comprising the amino acid sequence of SEQ ID NO: 138; and / or a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a light chain variable region (VL) comprising the amino acid sequence of SEQ ID NO: 134 or 148.

[0202] In some embodiments, B1 comprises a heavy chain CDR1 comprising the amino acidsequence of SEQ ID NO: 139, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 140, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 141.

[0203] In some embodiments, B1 comprises a light chain CDR1 comprising the amino acidsequence of SEQ ID NO: 135, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 136, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 137.

[0204] In some embodiments, B1 comprises a heavy chain CDR1 comprising the amino acidsequence of SEQ ID NO: 139, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 140, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 141; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 135, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 136, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 137.

[0205] In some embodiments, B1 comprises a VH comprising an amino acid sequence of SEQID NO: 138, and a VL comprising an amino acid sequence of SEQ ID NO: 134 or 148.

[0206] In some embodiments, B2 comprises a heavy chain complementarity determiningregion 1 (CDR1), a heavy chain CDR2, a heavy chain CDR3 of a heavy chain variable region (VH) comprising the amino acid sequence of SEQ ID NO: 144, 152, 156, 162, 167, 173, or 178; and / or a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a light chain variable region (VL) comprising the amino acid sequence of SEQ ID NO: 71, 151, 160, 165, 172, 176, or 180.

[0207] In some embodiments, B2 comprises:a) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 144, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71; b) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 152, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 151; c) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 156, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71; d) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 162, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 160; e) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 167, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 165; f) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 173, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 172; g) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 178, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 176; or h) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 167, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 180.

[0208] In some embodiments, B2 comprises:a) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 145, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 146; b) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 145, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 153; c) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 157, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 146; d) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 157, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 153; or e) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 168, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 169, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 170.

[0209] In some embodiments, B2 comprises:a) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; b) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 161; c) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 166; d) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 177; ore) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 181.

[0210] In some embodiments, B2 comprises:a) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 145, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 146; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; b) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 145, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 153; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; c) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 157, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 146; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; d) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 157, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 153; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 161; e) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 168, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 169, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 170; and a light chain CDR1comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 166; f) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 168, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 169, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 170; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 177; or g) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 168, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 169, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 170; or and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 181.

[0211] In some embodiments, B2 comprises a VH comprising an amino acid sequence of SEQID NO: 144, 152, 156, 162, 167, 173, or 178; and / or a VL comprising an amino acid sequence of SEQ ID NO: 71, 151, 160, 165, 172, 176, or 180.

[0212] In some embodiments, B2 comprises:a) a VH comprising an amino acid sequence of SEQ ID NO: 144, and a VL comprising an amino acid sequence of SEQ ID NO: 71; b) a VH comprising an amino acid sequence of SEQ ID NO: 152, and a VL comprising an amino acid sequence of SEQ ID NO: 151; c) a VH comprising an amino acid sequence of SEQ ID NO: 156, and a VL comprising an amino acid sequence of SEQ ID NO: 71; d) a VH comprising an amino acid sequence of SEQ ID NO: 162, and a VL comprising an amino acid sequence of SEQ ID NO: 160; e) a VH comprising an amino acid sequence of SEQ ID NO: 167, and a VL comprising an amino acid sequence of SEQ ID NO: 165; f) a VH comprising an amino acid sequence of SEQ ID NO: 173, and a VL comprising an amino acid sequence of SEQ ID NO: 172;g) a VH comprising an amino acid sequence of SEQ ID NO: 178, and a VL comprising an amino acid sequence of SEQ ID NO: 176; or h) a VH comprising an amino acid sequence of SEQ ID NO: 167, and a VL comprising an amino acid sequence of SEQ ID NO: 180.

[0213] In some embodiments, the platelet-derived growth factor receptor beta (PDGFRb)protein consists of the amino acid sequence of SEQ ID NO: 249, the breakpoint cluster region (BCR) protein consists of the amino acid sequence of SEQ ID NO: 250, the protein tyrosine phosphatase (PTPN11) protein consists of the amino acid sequence of SEQ ID NO: 251, and the fibroblast growth factor receptor substrate 2 (FRS2) protein consists of the amino acid sequence of SEQ ID NO: 252.

[0214] In some embodiments, the first linker sequence and / or the second linker sequencecomprises the amino acid sequence GILGSGGGGSGGGGSGGGGS (SEQ ID NO: 15) or GILSGSSSSGSSSSGSSSSG (SEQ ID NO: 32).

[0215] In some embodiments, the third linker sequence is 15-30 amino acids in length.

[0216] In some embodiments, the third linker sequence comprises the amino acid sequence(SSSSG)3-SS (SEQ ID NO: 31), (SSSSG)4-SS (SEQ ID NO: 34), or (SSSSG)5-SS (SEQ ID NO: 35).

[0217] In some embodiments, the fourth linker sequence comprises the amino acid sequenceKLLQASGGGGSGGGGSGGGGSAS (SEQ ID NO: 30) or amino acid sequence KLNSSTIESSYPYDVPDYALQASPAAPAPASPAAPAPSAPAASPAAPAPASPAAPAPSAAS PASSSSGSSSSGSSSSGAPRPAAPAPASPAAPAPSAPAGGGGSGGGGSGGGGSARPAAPA PASPAAPAPSAPAGGGGSGGGGSGGGGSARPAAPAPASPAAPAPSAPAGGGGSGGGGS GGGGSARPAAPAPASPAAPAPSAPAGGGGSGGGGSGGGGSAS (SEQ ID NO: 147).

[0218] In some embodiments, the anchoring protein is Aga2 anchoring protein.

[0219] In some embodiments, the Aga2 anchoring protein comprises the amino acid sequenceMQLLRCFSIFSVIASVLAQELTTICEQIPSPTLESTPYSLSTTTILANGKAMQGVFEYYKSV TFVSNCGSHPSTTSKGSPINTQYVF (SEQ ID NO: 29).

[0220] In some embodiments, the cell is a yeast cell.

[0221] In some embodiments, the amino acid sequence of SEQ ID NO: 38, 39, 40, 49, 50, 51,58, 59, 60, 68, 69, 70, 77, 81, 86, 90, 96, 105, 106, 109, 114, 116, 119, 126, 128, 130, 133, 149,154, 158, 163, 171, 174, 179, or 182, or an amino acid sequence having at least 75% identity thereto.

[0222] Also provided herein is a multispecific antibody or an antigen-binding fragment thereofcomprising: a) a first binding unit (B1) comprising a first scFv, said first scFv comprising a first antigen-binding domain (“ABD1”) that specifically binds to a first epitope of a target protein, wherein the first epitope includes an amino acid residue harboring one or more of a post- translational modification (PTM); and b) a second binding unit (B2) comprising a second scFv, said second scFv comprising a second antigen-binding domain (“ABD2”) that specifically binds to both the first binding unit (B1) and a second epitope of the target protein, wherein the second epitope does not include the PTM; wherein: (i) the variable regions of the first scFv are connected by a first linker sequence and the variable regions of the second scFv are connected by a second linker sequence; (ii) each of the first scFv and the second scFv is operably linked to an Fc domain via a third linker sequence, said third linker sequence being 10 to 40 amino acids in length; (iii) a hinge sequence separates the third linker sequence and the Fc domain(s); and (iv) one of the Fc domains comprises a knob mutation and the other of the Fc domains comprises a hole mutation.

[0223] In some embodiments, the PTM is selected from methylation, phosphorylation,acetylation, ubiquitination, glycosylation, formylation, propinylation, butyrylation, crotonylation, benzoylation, 2-hydroxyisobutyrylation, hydroxybutyrylation, lactylation, malonylation, succinylation, glutarylation, hydroxylation, sumoylation, ufmylation, biotinylation, serotonylation, dopaminylation, isomerization, myristoylation, sulfation, nitrosylation, ADP- ribosylation, prenylation, palmitoylation, deamidation, and proteolytic cleavage.

[0224] In some embodiments, the PTM is methylation or phosphorylation.

[0225] In some embodiments, the PTM is comprised within a flexible, disordered region of thetarget protein that does not form a fixed three-dimensional (3D) structure.

[0226] In some embodiments, the target protein is a histone protein, a platelet-derived growthfactor receptor beta (PDGFRb) protein, a breakpoint cluster region (BCR) protein, a proteintyrosine phosphatase (PTPN11) protein, or a fibroblast growth factor receptor substrate 2 (FRS2) protein.

[0227] In some embodiments, the target protein is a histone protein, or a fragment thereof.

[0228] In some embodiments, the histone protein is a histone H3 protein, or fragment thereof,or a histone H4 protein, or fragment thereof.

[0229] In some embodiments, the histone protein is a histone H3 protein, or fragment thereof.

[0230] In some embodiments, the histone protein is a histone H4 protein, or fragment thereof.

[0231] In some embodiments, the first epitope includes a lysine (K) residue that is methylatedone or more times.

[0232] In some embodiments, the lysine (K) residue is trimethylated.

[0233] In some embodiments, the lysine (K) residue is positioned at amino acid position 9, 27,or 56 of the histone H3 protein, or a fragment thereof.

[0234] In some embodiments, the lysine (K) residue is positioned at amino acid position 20 ofthe histone H4 protein, or a fragment thereof.

[0235] In some embodiments, B1 comprises:a) a heavy chain complementarity determining region 1 (CDR1), a heavy chain CDR2, a heavy chain CDR3 of a heavy chain variable region (VH) comprising the amino acid sequence of SEQ ID NO: 6; and / or a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a light chain variable region (VL) comprising the amino acid sequence of SEQ ID NO: 1; or b) a heavy chain complementarity determining region 1 (CDR1), a heavy chain CDR2, a heavy chain CDR3 of a heavy chain variable region (VH) comprising the amino acid sequence of SEQ ID NO: 6; and / or a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a light chain variable region (VL) comprising the amino acid sequence of SEQ ID NO: 2.

[0236] In some embodiments, B1 comprises a heavy chain CDR1 comprising the amino acidsequence of SEQ ID NO: 7, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 8, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 9.

[0237] In some embodiments, B1 comprises a light chain CDR1 comprising the amino acidsequence of SEQ ID NO: 3, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 4, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 5.

[0238] In some embodiments, B1 comprises a heavy chain CDR1 comprising the amino acidsequence of SEQ ID NO: 7, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 8, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 9; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 3, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 4, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 5.

[0239] In some embodiments, B1 comprises a VH comprising an amino acid sequence of SEQID NO: 6, and a VL comprising an amino acid sequence of SEQ ID NO: 1 or 2.

[0240] In some embodiments, B2 comprises a heavy chain complementarity determiningregion 1 (CDR1), a heavy chain CDR2, a heavy chain CDR3 of a heavy chain variable region (VH) comprising the amino acid sequence of SEQ ID NO: 25, 43, 54, 63, 73, 80, 84, 89, 93, 108, 115, 124, 127, 129, or 131; and / or a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a light chain variable region (VL) comprising the amino acid sequence of SEQ ID NO: 21, 41, 52, 61, 71, 78, 82, 87, 91, 103, 112, 117, or 122.

[0241] In some embodiments, B2 comprises:a) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 25, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 21; b) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 43, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 41; c) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 54, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 52; d) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 63, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 61; e) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 73, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71;f) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 80, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 78; g) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 84, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 82; h) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 89, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 87; i) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 93, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 91; j) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 93, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 103; k) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 93, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71; l) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 108, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71; m) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 93, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 112; n) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 115, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71; o) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 93, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 117;p) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 124, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 122; q) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 127, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 122; r) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 129, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 122; or s) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 131, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 122.

[0242] In some embodiments, B2 comprises:a) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 26, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 28; b) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 46; c) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 26, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 55; d) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 65; e) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 74, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76; f) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76;g) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 74, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 85; h) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76; i) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; j) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; k) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 125; or l) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 132.

[0243] In some embodiments, B2 comprises:a) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 24; b) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 42; c) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 53; d) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 62;e) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; f) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 79; g) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 83; h) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 88; i) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 92; j) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 104; k) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 113; l) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 118; or m) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 123.

[0244] In some embodiments, B2 comprises:a) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 26, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 28; and a light chain CDR1comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 24; b) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 46; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 42; c) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 26, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 55; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 53; d) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 65; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 62; e) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 74, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; f) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising theamino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 79; g) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 74, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 85; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 83; h) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 88; i) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 92; j) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 104; k) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising theamino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; l) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 113; m) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; n) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 118; o) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 125; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 123; or p) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 132; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising theamino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 123.

[0245] In some embodiments, B2 comprises:a) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 92; b) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; or c) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 118.

[0246] In some embodiments, B2 comprises a VH comprising an amino acid sequence of SEQID NO: 25, 43, 54, 63, 73, 80, 84, 89, 93, 108, 115, 124, 127, 129, or 131; and / or a VL comprising an amino acid sequence of SEQ ID NO: 21, 41, 52, 61, 71, 78, 82, 87, 91, 103, 112, 117, or 122.

[0247] In some embodiments, B2 comprises a VH comprising an amino acid sequence of SEQID NO: 93 or 108; and / or a VL comprising an amino acid sequence of SEQ ID NO: 71, 91, or 117.

[0248] In some embodiments, B2 comprises:a) a VH comprising an amino acid sequence of SEQ ID NO: 25, and a VL comprising an amino acid sequence of SEQ ID NO: 21;b) a VH comprising an amino acid sequence of SEQ ID NO: 43, and a VL comprising an amino acid sequence of SEQ ID NO: 41; c) a VH comprising an amino acid sequence of SEQ ID NO: 54, and a VL comprising an amino acid sequence of SEQ ID NO: 52; d) a VH comprising an amino acid sequence of SEQ ID NO: 63, and a VL comprising an amino acid sequence of SEQ ID NO: 61; e) a VH comprising an amino acid sequence of SEQ ID NO: 73, and a VL comprising an amino acid sequence of SEQ ID NO: 71; f) a VH comprising an amino acid sequence of SEQ ID NO: 80, and a VL comprising an amino acid sequence of SEQ ID NO: 78; g) a VH comprising an amino acid sequence of SEQ ID NO: 84, and a VL comprising an amino acid sequence of SEQ ID NO: 82; h) a VH comprising an amino acid sequence of SEQ ID NO: 89, and a VL comprising an amino acid sequence of SEQ ID NO: 87; i) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VL comprising an amino acid sequence of SEQ ID NO: 91; j) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VL comprising an amino acid sequence of SEQ ID NO: 103; k) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VL comprising an amino acid sequence of SEQ ID NO: 71; l) a VH comprising an amino acid sequence of SEQ ID NO: 108, and a VL comprising an amino acid sequence of SEQ ID NO: 71; m) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VL comprising an amino acid sequence of SEQ ID NO: 112; n) a VH comprising an amino acid sequence of SEQ ID NO: 115, and a VL comprising an amino acid sequence of SEQ ID NO: 71; o) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VL comprising an amino acid sequence of SEQ ID NO: 117; p) a VH comprising an amino acid sequence of SEQ ID NO: 124, and a VL comprising an amino acid sequence of SEQ ID NO: 122;q) a VH comprising an amino acid sequence of SEQ ID NO: 127, and a VL comprising an amino acid sequence of SEQ ID NO: 122; r) a VH comprising an amino acid sequence of SEQ ID NO: 129, and a VL comprising an amino acid sequence of SEQ ID NO: 122; or s) a VH comprising an amino acid sequence of SEQ ID NO: 131, and a VL comprising an amino acid sequence of SEQ ID NO: 122.

[0249] In some embodiments, B2 comprises:a) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VL comprising an amino acid sequence of SEQ ID NO: 91; b) a VH comprising an amino acid sequence of SEQ ID NO: 108, and a VL comprising an amino acid sequence of SEQ ID NO: 71; or c) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VL comprising an amino acid sequence of SEQ ID NO: 117.

[0250] In some embodiments, the histone H3 protein consists of the amino acid sequence ofany one of SEQ ID NOs: 240-247 and the histone H4 protein consists of the amino acid sequence of SEQ ID NO: 248.

[0251] In some embodiments, the target protein is a platelet-derived growth factor receptorbeta (PDGFRb) protein, a breakpoint cluster region (BCR) protein, a protein tyrosine phosphatase (PTPN11) protein, or a fibroblast growth factor receptor substrate 2 (FRS2) protein.

[0252] In some embodiments, the target protein is a platelet-derived growth factor receptorbeta (PDGFRb) protein, or a fragment thereof, or a breakpoint cluster region (BCR) protein, or a fragment thereof.

[0253] In some embodiments, the first epitope includes a tyrosine (Y) residue that isphosphorylated once.

[0254] In some embodiments, the target protein is a platelet-derived growth factor receptorbeta (PDGFRb) protein, or a fragment thereof, and the tyrosine (Y) residue is positioned at amino acid position 716 of the PDGFRb protein, or a fragment thereof.

[0255] In some embodiments, the target protein is a breakpoint cluster region (BCR) protein,or a fragment thereof, and the tyrosine (Y) residue is positioned at amino acid position 177 of the BCR protein, or a fragment thereof.

[0256] In some embodiments, the target protein is a protein tyrosine phosphatase (PTPN11)protein, or a fragment thereof, and the tyrosine (Y) residue is positioned at amino acid position 580 of the PTPN11 protein, or a fragment thereof.

[0257] In some embodiments, the target protein is a fibroblast growth factor receptor substrate2 (FRS2) protein, or a fragment thereof, and the tyrosine (Y) residue is positioned at amino acid position 196 of the FRS2 protein, or a fragment thereof.

[0258] In some embodiments, B1 comprises a heavy chain complementarity determiningregion 1 (CDR1), a heavy chain CDR2, a heavy chain CDR3 of a heavy chain variable region (VH) comprising the amino acid sequence of SEQ ID NO: 138; and / or a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a light chain variable region (VL) comprising the amino acid sequence of SEQ ID NO: 134 or 148.

[0259] In some embodiments, B1 comprises a heavy chain CDR1 comprising the amino acidsequence of SEQ ID NO: 139, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 140, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 141.

[0260] In some embodiments, B1 comprises a light chain CDR1 comprising the amino acidsequence of SEQ ID NO: 135, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 136, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 137.

[0261] In some embodiments, B1 comprises a heavy chain CDR1 comprising the amino acidsequence of SEQ ID NO: 139, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 140, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 141; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 135, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 136, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 137.

[0262] In some embodiments, B1 comprises a VH comprising an amino acid sequence of SEQID NO: 138, and a VL comprising an amino acid sequence of SEQ ID NO: 134 or 148.

[0263] In some embodiments, B2 comprises a heavy chain complementarity determiningregion 1 (CDR1), a heavy chain CDR2, a heavy chain CDR3 of a heavy chain variable region (VH) comprising the amino acid sequence of SEQ ID NO: 144, 152, 156, 162, 167, 173, or 178; and / or a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a light chain variable region (VL) comprising the amino acid sequence of SEQ ID NO: 71, 151, 160, 165, 172, 176, or 180.

[0264] In some embodiments, B2 comprises:a) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 144, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71; b) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 152, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 151; c) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 156, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71; d) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 162, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 160; e) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 167, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 165; f) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 173, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 172; g) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 178, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 176; or h) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 167, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 180.

[0265] In some embodiments, B2 comprises:a) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 145, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 146;b) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 145, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 153; c) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 157, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 146; d) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 157, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 153; or e) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 168, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 169, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 170.

[0266] In some embodiments, B2 comprises:a) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; b) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 161; c) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 166; d) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 177; or e) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 181.

[0267] In some embodiments, B2 comprises:a) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 145, and a heavy chainCDR3 comprising the amino acid sequence of SEQ ID NO: 146; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; b) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 145, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 153; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; c) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 157, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 146; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; d) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 157, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 153; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 161; e) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 168, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 169, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 170; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 166; f) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 168, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 169, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 170; and a light chain CDR1comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 177; or g) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 168, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 169, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 170; or and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 181.

[0268] In some embodiments, B2 comprises:a) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 145, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 146; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; b) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 145, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 153; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; c) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 157, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 146; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; d) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 157, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 153; and a light chain CDR1comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 161; e) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 168, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 169, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 170; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 166; or f) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 168, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 169, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 170; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 181.

[0269] In some embodiments, B2 comprises a VH comprising an amino acid sequence of SEQID NO: 144, 152, 156, 162, 167, 173, or 178; and / or a VL comprising an amino acid sequence of SEQ ID NO: 71, 151, 160, 165, 172, 176, or 180.

[0270] In some embodiments, B2 comprises a VH comprising an amino acid sequence of SEQID NO: 144, 152, 156, 162, 167, or 173; and / or a VL comprising an amino acid sequence of SEQ ID NO: 71, 151, 160, 172, or 180.

[0271] In some embodiments, B2 comprises:a) a VH comprising an amino acid sequence of SEQ ID NO: 144, and a VL comprising an amino acid sequence of SEQ ID NO: 71; b) a VH comprising an amino acid sequence of SEQ ID NO: 152, and a VL comprising an amino acid sequence of SEQ ID NO: 151; c) a VH comprising an amino acid sequence of SEQ ID NO: 156, and a VL comprising an amino acid sequence of SEQ ID NO: 71; d) a VH comprising an amino acid sequence of SEQ ID NO: 162, and a VL comprising an amino acid sequence of SEQ ID NO: 160;e) a VH comprising an amino acid sequence of SEQ ID NO: 167, and a VL comprising an amino acid sequence of SEQ ID NO: 165; f) a VH comprising an amino acid sequence of SEQ ID NO: 173, and a VL comprising an amino acid sequence of SEQ ID NO: 172; g) a VH comprising an amino acid sequence of SEQ ID NO: 178, and a VL comprising an amino acid sequence of SEQ ID NO: 176; or h) a VH comprising an amino acid sequence of SEQ ID NO: 167, and a VL comprising an amino acid sequence of SEQ ID NO: 180.

[0272] In some embodiments, B2 comprises:a) a VH comprising an amino acid sequence of SEQ ID NO: 144, and a VL comprising an amino acid sequence of SEQ ID NO: 71; b) a VH comprising an amino acid sequence of SEQ ID NO: 152, and a VL comprising an amino acid sequence of SEQ ID NO: 151; c) a VH comprising an amino acid sequence of SEQ ID NO: 156, and a VL comprising an amino acid sequence of SEQ ID NO: 71; d) a VH comprising an amino acid sequence of SEQ ID NO: 162, and a VL comprising an amino acid sequence of SEQ ID NO: 160; e) a VH comprising an amino acid sequence of SEQ ID NO: 173, and a VL comprising an amino acid sequence of SEQ ID NO: 172; or f) a VH comprising an amino acid sequence of SEQ ID NO: 167, and a VL comprising an amino acid sequence of SEQ ID NO: 180.

[0273] In some embodiments, the platelet-derived growth factor receptor beta (PDGFRb)protein consists of the amino acid sequence of SEQ ID NO: 249, the breakpoint cluster region (BCR) protein consists of the amino acid sequence of SEQ ID NO: 250, the protein tyrosine phosphatase (PTPN11) protein consists of the amino acid sequence of SEQ ID NO: 251, and the fibroblast growth factor receptor substrate 2 (FRS2) protein consists of the amino acid sequence of SEQ ID NO: 252.

[0274] In some embodiments, the first linker sequence and / or the second linker sequencecomprises the amino acid sequence GILGSGGGGSGGGGSGGGGS (SEQ ID NO: 15) or GILSGSSSSGSSSSGSSSSG (SEQ ID NO: 32).

[0275] In some embodiments, the third linker sequence is 15-30 amino acids in length.

[0276] In some embodiments, the third linker sequence comprises the amino acid sequence(SSSSG)3-SS (SEQ ID NO: 31), (SSSSG)4-SS (SEQ ID NO: 34), or (SSSSG)5-SS (SEQ ID NO: 35).

[0277] In some embodiments, the hinge sequence comprises the amino acid sequenceGCKPCICT (SEQ ID NO: 17).

[0278] In some embodiments, one or both of the Fc domain(s) are derived from an IgGantibody.

[0279] In some embodiments, the IgG antibody is of IgG1, IgG2, IgG3, or IgG4 subclass.

[0280] In some embodiments, the IgG antibody is of IgG1 subclass.

[0281] In some embodiments, one or both of the Fc domain(s) comprise a S239C mutation.

[0282] In some embodiments, the Fc domains dimerize to form an Fc heterodimer.

[0283] In some embodiments, the Fc domains in the Fc heterodimer comprise knob-in-holemutations as compared to a wild-type Fc domain.

[0284] In some embodiments, one Fc domain in the Fc heterodimer comprises amino acidsubstitutions P354C and T366W (according to EU numbering) as compared to a wild-type Fc domain, and the other Fc domain in the Fc heterodimer comprises amino acid substitutions Y349C, T366S, M368A, and Y407V (according to EU numbering) as compared to a wild-type Fc domain.

[0285] In some embodiments, one of the Fc domains in the Fc heterodimer comprises theamino acid sequence of SEQ ID NO: 187, and the other of the Fc domains in the Fc heterodimer comprises the amino acid sequence of SEQ ID NO: 188.

[0286] In some embodiments, the multispecific antibody or antigen-binding fragment thereofcomprises two polypeptide chains, wherein the first polypeptide chain comprises the amino acid sequence of SEQ ID NO: 20 or 143, or an amino acid sequence having at least 75% identity thereto, and the second polypeptide chain comprises the amino acid sequence of SEQ ID NO: 102, 111, 121, 150, 155, 159, 164, 175, or 183, or an amino acid sequence having at least 75% identity thereto.

[0287] In some embodiments, the multispecific antibody or antigen-binding fragment thereofcomprises: a) a first polypeptide chain comprising an amino acid sequence of SEQ ID NO: 20, or an amino acid sequence having at least 75% identity thereto; and a second comprising an aminoacid sequence of SEQ ID NO: 102; or an amino acid sequence having at least 75% identity thereto; b) a first polypeptide chain comprising an amino acid sequence of SEQ ID NO: 20, or an amino acid sequence having at least 75% identity thereto; and a second comprising an amino acid sequence of SEQ ID NO: 111; or an amino acid sequence having at least 75% identity thereto; c) a first polypeptide chain comprising an amino acid sequence of SEQ ID NO: 20, or an amino acid sequence having at least 75% identity thereto; and a second comprising an amino acid sequence of SEQ ID NO: 121; or an amino acid sequence having at least 75% identity thereto; d) a first polypeptide chain comprising an amino acid sequence of SEQ ID NO: 143, or an amino acid sequence having at least 75% identity thereto; and a second comprising an amino acid sequence of SEQ ID NO: 150; or an amino acid sequence having at least 75% identity thereto; e) a first polypeptide chain comprising an amino acid sequence of SEQ ID NO: 143, or an amino acid sequence having at least 75% identity thereto; and a second comprising an amino acid sequence of SEQ ID NO: 155; or an amino acid sequence having at least 75% identity thereto; f) a first polypeptide chain comprising an amino acid sequence of SEQ ID NO: 143, or an amino acid sequence having at least 75% identity thereto; and a second comprising an amino acid sequence of SEQ ID NO: 159; or an amino acid sequence having at least 75% identity thereto; g) a first polypeptide chain comprising an amino acid sequence of SEQ ID NO: 143, or an amino acid sequence having at least 75% identity thereto; and a second comprising an amino acid sequence of SEQ ID NO: 164; or an amino acid sequence having at least 75% identity thereto; h) a first polypeptide chain comprising an amino acid sequence of SEQ ID NO: 143, or an amino acid sequence having at least 75% identity thereto; and a second comprising an amino acid sequence of SEQ ID NO: 175; or an amino acid sequence having at least 75% identity thereto; ori) a first polypeptide chain comprising an amino acid sequence of SEQ ID NO: 143, or an amino acid sequence having at least 75% identity thereto; and a second comprising an amino acid sequence of SEQ ID NO: 183; or an amino acid sequence having at least 75% identity thereto.

[0288] In some embodiments, the antibody fusion molecule or the multispecific antibody orantigen-binding fragment thereof further comprises one or more of a reporter protein or an protein tag.

[0289] In some embodiments, the protein tag is an affinity tag.

[0290] In some embodiments, the reporter protein or the protein tag is a V5 epitope tag (V5-tag), an biotinylation tag, a polyhistidine tag (His-tag), a fluorescent protein, a c-myc tag, a glutathione S-transferase (GST) tag, a FLAG tag, an HA tag, an S-tag, a FLASH tag, a SNAP- tag, a streptavidin moiety, a Strep II tag, an HA tag, an L14 tag, a 4C-RGD tag, an LH tag, a protein A, a maltose-binding protein (MBP), an albumin-binding protein, a chitin binding domain, a calmodulin binding peptide, a cellulose binding domain, or a biotin moiety, an oligonucleotide (oligo), or a horseradish peroxidase (HRP).

[0291] In some embodiments, the reporter protein or the protein tag is a V5 epitope tag (V5-tag), a biotinylation tag, or a polyhistidine tag (His-tag).

[0292] In some embodiments, the V5-tag comprises the amino acid sequenceGKPIPNPLLGLDST (SEQ ID NO: 33).

[0293] In some embodiments, the His-tag comprises the amino acid sequence HHHHHH (SEQID NO: 99).

[0294] Also provided herein is an antibody conjugate comprising the antibody or combinationof antibodies or antigen-binding fragment(s) thereof as described herein, the antibody fusion molecule as described herein, or the multispecific antibody or antigen-binding fragment thereof as described herein, conjugated to a heterologous moiety.

[0295] In some embodiments, the heterologous moiety is one or more of a reporter protein or aprotein tag capable of being used for molecular detection.

[0296] In some embodiments, the protein tag is an affinity tag.

[0297] In some embodiments, the reporter protein or the protein tag is a V5 epitope tag (V5-tag), an biotinylation tag, a polyhistidine tag (His-tag), a fluorescent protein, a c-myc tag, a glutathione S-transferase (GST) tag, a FLAG tag, an HA tag, an S-tag, a FLASH tag, a SNAP-tag, a streptavidin moiety, a Strep II tag, an HA tag, an L14 tag, a 4C-RGD tag, an LH tag, a protein A, a maltose-binding protein (MBP), an albumin-binding protein, a chitin binding domain, a calmodulin binding peptide, a cellulose binding domain, a biotin moiety, an oligonucleotide (oligo), or a horseradish peroxidase (HRP).

[0298] In some embodiments, the reporter protein or the protein tag is a V5 epitope tag (V5-tag), a biotinylation tag, or a polyhistidine tag (His-tag).

[0299] In some embodiments, the reporter protein or the protein tag is a fluorescent protein, anoligonucleotide (oligo), a horseradish peroxidase (HRP), or a biotinylation tag.

[0300] In some embodiments, the molecular detection is immunoprecipitation (IP), westernblot, dot blot, immunofluorescence (IF), immunohistochemistry (IHC), immunocytochemistry (ICC), enzyme-linked immunosorbent assay (ELISA), or flow cytometry.

[0301] In some embodiments, the immunoprecipitation (IP) comprises chromatinimmunoprecipitation (ChIP).

[0302] In some embodiments, the molecular detection occurs in a cell of a cancer or a cellularcomponent thereof.

[0303] In some embodiments, the molecular detection occurs in vitro.

[0304] In some embodiments, the molecular detection occurs ex vivo.

[0305] In some embodiments, the molecular detection occurs in vivo.

[0306] In some embodiments, the cancer cell is sampled from a subject in need thereof or is ina subject in need thereof.

[0307] In some embodiments, the cancer is a hematologic cancer or solid cancer.

[0308] In some embodiments, the hematologic cancer is leukemia.

[0309] In some embodiments, the leukemia is acute myeloid leukemia (AML), acutelymphoblastic leukemia (ALL), acute leukemia of ambiguous lineage, chronic myeloid neoplasm, non-Hodgkin lymphoma, Hodgkin lymphoma, chronic leukemia, dendritic / histiocytic neoplasm, or lymphoproliferative disorder.

[0310] In some embodiments, the solid cancer is glioma, thyroid cancer, lung cancer,colorectal cancer, head and neck cancer, esophageal cancer, gastric cancer, stomach cancer, liver cancer, pancreatic cancer, renal cancer, urothelial cancer, prostate cancer, testis cancer, breast cancer, cervical cancer, endometrial cancer, ovarian cancer, gallbladder cancer, sarcoma, melanoma, or malignant peripheral nerve sheath tumors (MPNSTs).

[0311] In some embodiments, the solid cancer is lung cancer, colorectal cancer, esophagealcancer, stomach cancer, liver cancer, renal cancer, prostate cancer, breast cancer, or malignant peripheral nerve sheath tumors (MPNSTs).

[0312] In some embodiments, the antibody conjugate is an antibody-drug conjugate (ADC).

[0313] In some embodiments, the heterologous moiety is a cytotoxic agent, an siRNA, aradionucleotide, a peptide, or an immune-modulatory agent.

[0314] In some embodiments, the subject is human.

[0315] Also provided herein is a polynucleotide encoding the antibody or combination ofantibodies or antigen-binding fragment(s) thereof as described herein, the antibody fusion molecule as described herein, or the multispecific antibody or antigen-binding fragment thereof as described herein.

[0316] Further provided herein is a vector comprising the polynucleotide as described herein.

[0317] Additionally provided herein is a host cell expressing the antibody or combination ofantibodies or antigen-binding fragment(s) thereof as described herein, the antibody fusion molecule as described herein, or the multispecific antibody or antigen-binding fragment thereof as described herein, comprising the polynucleotide as described herein or the vector as described herein.

[0318] In some embodiments, the cell is a hybridoma.

[0319] In some embodiments, the antibody or combination of antibodies or antigen-bindingfragment(s) thereof, the antibody fusion molecule, or the multispecific antibody or antigen- binding fragment thereof is recombinantly produced.

[0320] Further provided herein is a method of producing a host cell expressing the antibody orcombination of antibodies or antigen-binding fragment(s) thereof as described herein, the antibody fusion molecule as described herein, or the multispecific antibody or antigen-binding fragment thereof as described herein, wherein said method comprises culturing the host cell as described herein, and isolating said antibody or combination of antibodies or antigen-binding fragment(s) thereof, said antibody fusion molecule, or said multispecific antibody or antigen- binding fragment thereof.

[0321] Further provided herein is a pharmaceutical composition comprising the antibody orcombination of antibodies or antigen-binding fragment(s) thereof as described herein, the antibody fusion molecule as described herein, the multispecific antibody or antigen-bindingfragment thereof as described herein, the antibody conjugate as described herein, the polynucleotide as described herein, or the vector as described herein, and a pharmaceutically acceptable carrier or diluent.

[0322] Also provided herein is a kit comprising (i) the antibody or combination of antibodiesor antigen-binding fragment(s) thereof as described herein, the antibody fusion molecule as described herein, the multispecific antibody or antigen-binding fragment thereof as described herein, the antibody conjugate as described herein, the polynucleotide as described herein, the vector as described herein, or the pharmaceutical composition as described herein, and (ii) packaging for the same.

[0323] Additionally provided herein is a method for detecting a cell expressing a targetprotein, said target protein including an amino acid residue harboring one or more of a post- translational modification (PTM), the method comprising contacting the cell with the antibody or combination of antibodies or antigen-binding fragment(s) thereof as described herein, the antibody fusion molecule as described herein, the multispecific antibody or antigen-binding fragment thereof as described herein, or the antibody conjugate as described herein.

[0324] Further provided herein is a method of killing a cell expressing a target protein, saidtarget protein including an amino acid residue harboring one or more of a post-translational modification (PTM), the method comprising contacting the cell with an effective amount of the antibody or combination of antibodies or antigen-binding fragment(s) thereof as described herein, the antibody fusion molecule as described herein, the multispecific antibody or antigen- binding fragment thereof as described herein, the antibody conjugate as described herein, the polynucleotide as described herein, the vector as described herein, or the pharmaceutical composition as described herein.

[0325] In some embodiments, the PTM is selected from methylation, phosphorylation,acetylation, ubiquitination, glycosylation, formylation, propinylation, butyrylation, crotonylation, benzoylation, 2-hydroxyisobutyrylation, hydroxybutyrylation, lactylation, malonylation, succinylation, glutarylation, hydroxylation, sumoylation, ufmylation, biotinylation, serotonylation, dopaminylation, isomerization, myristoylation, sulfation, nitrosylation, ADP- ribosylation, prenylation, palmitoylation, deamidation, and proteolytic cleavage.

[0326] In some embodiments, the PTM is methylation or phosphorylation.

[0327] In some embodiments, the PTM is comprised within a flexible, disordered region of thetarget protein that does not form a fixed three-dimensional (3D) structure.

[0328] In some embodiments, the target protein is a histone protein, a platelet-derived growthfactor receptor beta (PDGFRb) protein, a breakpoint cluster region (BCR) protein, a protein tyrosine phosphatase (PTPN11) protein, or a fibroblast growth factor receptor substrate 2 (FRS2) protein.

[0329] In some embodiments, the cell is a cell of a cancer.

[0330] In some embodiments, the contacting occurs in vitro.

[0331] In some embodiments, the contacting occurs ex vivo.

[0332] In some embodiments, the contacting occurs in vivo.

[0333] In some embodiments, the cancer cell is sampled from a subject in need thereof or is ina subject in need thereof.

[0334] Also provided herein is a method of treating or preventing a cancer associated with atarget protein in a subject in need thereof, said target protein including an amino acid residue harboring one or more of a post-translational modification (PTM), comprising administering to the subject an effective amount of the antibody or combination of antibodies or antigen-binding fragment(s) thereof as described herein, the antibody fusion molecule as described herein, the multispecific antibody or antigen-binding fragment thereof as described herein, the antibody conjugate as described herein, the polynucleotide as described herein, the vector as described herein, or the pharmaceutical composition as described herein.

[0335] In some embodiments, the PTM is selected from methylation, phosphorylation,acetylation, ubiquitination, glycosylation, formylation, propinylation, butyrylation, crotonylation, benzoylation, 2-hydroxyisobutyrylation, hydroxybutyrylation, lactylation, malonylation, succinylation, glutarylation, hydroxylation, sumoylation, ufmylation, biotinylation, serotonylation, dopaminylation, isomerization, myristoylation, sulfation, nitrosylation, ADP- ribosylation, prenylation, palmitoylation, deamidation, and proteolytic cleavage.

[0336] In some embodiments, the PTM is methylation or phosphorylation.

[0337] In some embodiments, the PTM is comprised within a flexible, disordered region of thetarget protein that does not form a fixed three-dimensional (3D) structure.

[0338] In some embodiments, the target protein is a histone protein, a platelet-derived growthfactor receptor beta (PDGFRb) protein, a breakpoint cluster region (BCR) protein, a proteintyrosine phosphatase (PTPN11) protein, or a fibroblast growth factor receptor substrate 2 (FRS2) protein.

[0339] In some embodiments, the cancer is a hematologic cancer or solid cancer.

[0340] In some embodiments, the hematologic cancer is leukemia.

[0341] In some embodiments, the leukemia is acute myeloid leukemia (AML), acutelymphoblastic leukemia (ALL), acute leukemia of ambiguous lineage, chronic myeloid neoplasm, non-Hodgkin lymphoma, Hodgkin lymphoma, chronic leukemia, dendritic / histiocytic neoplasm, or lymphoproliferative disorder.

[0342] In some embodiments, the solid cancer is glioma, thyroid cancer, lung cancer,colorectal cancer, head and neck cancer, esophageal cancer, gastric cancer, stomach cancer, liver cancer, pancreatic cancer, renal cancer, urothelial cancer, prostate cancer, testis cancer, breast cancer, cervical cancer, endometrial cancer, ovarian cancer, gallbladder cancer, sarcoma, melanoma, or malignant peripheral nerve sheath tumors (MPNSTs).

[0343] In some embodiments, the solid cancer is lung cancer, colorectal cancer, esophagealcancer, stomach cancer, liver cancer, renal cancer, prostate cancer, breast cancer, or malignant peripheral nerve sheath tumors (MPNSTs).

[0344] In some embodiments, the method further comprises administering one or moreadditional therapeutic agents.

[0345] In some embodiments, the one or more additional therapeutic agents comprise one ormore chemotherapeutic agents, targeted therapies, stem cell transplantation, radiotherapy, or a combination thereof.

[0346] In some embodiments, the one or more chemotherapeutic agents comprises ananthracycline, cytarabine, all-trans-retinoic acid, arsenic trioxide, a hypomethylating agent, a BH-3 mimetic, temozolamide, hydroxyurea, 6-thioguanine, cyclophosphamide, gemtuzumab ozogamicin, midostaurin, ivosidenib, enasidenib, gilteritinib, glasdegib, quizartinib, olutasidenib, vincristine, or a combination thereof.

[0347] In some embodiments, the subject is human.BRIEF DESCRIPTION OF THE DRAWINGS

[0348] Figures 1A-1D show the binding mode-guided design of heterodimeric claspingantibodies. Figure 1A shows a schematic representation of IgG antibody. Figure 1B shows thestructure of homodimeric clasping antibody (PDB ID: 4YHP, left) and its schematic representation (middle cartoon). The right cartoon represents heterodimeric antigen clasping that is composed of two different antigen-binding units, PTM and enhancer units, resembling the distinct roles of Fabs in homodimeric antigen clasping. Figure 1C shows the binding analysis of PTM and enhancer Fabs to the H3K56me3 peptide with the peptide-IP assay. The peptide concentration used was 100 nM. The peptide binding was observed only when both PTM and enhancer Fabs were co-immobilized on beads, indicating cooperative binding of both Fabs in an antigen-clasping manner. Figure 1D shows the binding titration curves of PTM Fab alone and co-immobilized Fabs with the peptide IP assay. The apparent KD values, calculated from the curve fitting of a 1:1 binding model, to the target peptide are shown. Sequence specificity (top panels) and methylation-state specificity (bottom panels) were assessed. Data shown here were from triplicate measurements. Error bars indicate the s.d.

[0349] Figures 2A-2E show efficient identification of clasping antibodies by yeast display andcharacterization of anti-H3K27me3 antibody in ICeChIP. Figure 2A shows a schematic representation of the yeast-display format where the enhancer unit is tethered to the PTM unit with a long linker. Figure 2B shows characterization of clasping antibodies with the peptide IP assay in the yeast-display format harboring the 22-residue linker. Binding titration curves using the target peptides (left panels) and specificity test using off-target peptides (right panels) are shown. The apparent KD values were calculated from the curve fitting of a 1:1 binding model. The highest peptide concentrations used in the binding titration curves were utilized in the specificity test. Data shown here were from triplicate measurements. Error bars indicate the s.d. See also Figures 6, 7 for other clones. Figures 2C-2E show the performance comparison of the widely-used antibody and the clasping antibody to H3K27me3 in native ICeChIP. Figure 2C shows specificity of antibodies assessed by ICeChIP. The bottom cartoons represent the nucleosome standards bearing H3K4me3, H3K27me3 or both. Note that the different standards bearing the H3K27me3 have one or two instances of the mark per nucleosome. Antibody specificity was calculated as the percentage of off-target to on-target (H3K27me3) enrichment of nucleosome standards. The 3C2-H2 clasping antibody captured symmetric and asymmetric nucleosome standards in a less biased manner compared with C36B11 IgG. Figure 2D shows metagene and heatmap performance comparison of antibodies. Histone modification density (HMD) of H3K27me3 across all promoters in mESCs rank-ordered by their RNA-expressionlevel (RNA-seq from ENCODE) was plotted. Figure 2E shows a representative locus showing apparent H3K27me3 HMD with antibodies.

[0350] Figures 3A-3F show characterization of clasping antibodies to H3K27me3 in the long-neck scFv-Fc format. Figure 3A shows a schematic representation of the heterodimeric long- neck scFv-Fc format. Hetero-dimerization is facilitated by the knobs-into-holes mutations in the CH3 domain. Figure 3B shows binding titration curves of the clasping antibodies against the target and the off-target peptides with the peptide IP assay. The apparent KDvalues calculated from the curve fitting of a 1:1 binding model to the target peptide are shown. Data shown are from triplicate measurements. Figure 3C shows kinetic analysis of clasping antibodies with biolayer interferometry (BLI). The H3K27me3 peptide was immobilized, and the binding of soluble long-neck scFv-Fc antibodies was measured. The apparent KDvalues are from the global fit with a 1:1 binding model to the data. Figures 3D, 3E show validation of clasping antibodies in Western blot. Figure 3D shows whole-cell lysate of K562 cells blotted with the indicated long-neck scFv-Fc antibodies at three different concentrations (30, 10 and 3.3 nM, respectively). The isotype composes 4-5 (PTM unit) and a non-binding antibody (in replacement of an enhancer unit), and consequently has weak affinity to Kme3. The “secondary only” lanes refer to no primary antibody with anti-mouse Fc-HRP (secondary only 1) or with anti-rabbit IgG-HRP (secondary only 2). The arrow indicates the location of histone H3. Figure 3E shows whole-cell lysates from K562 cells treated with and without GSK126, an EZH2 methyltransferase inhibitor, which were blotted with indicated long-neck scFv-Fc antibodies. The vinculin protein was detected as a loading control. Figure 3F shows validation of 3C2-H2 long-neck scFv-Fc in native SNAP-ChIP. The enrichment (percentage of H3K27me3 nucleosome recovered after immunoprecipitation relative to input, top panel) and specificity (percentage of off-target immunoprecipitation relative to the on-target, bottom panel) assessed by qPCR are shown. The clasping antibody specifically captured the nucleosome bearing H3K27me3. Data shown are from triplicate measurements. Error bars indicate the s.d. See Figure 10 for the complete datasets for Western blot.

[0351] Figures 4A-4F show characterization of anti-pY clasping antibodies. Figures 4A-4Dshow characterization of clasping antibodies targeting PDGFRb pY716 in the long-neck scFv-Fc format. Figure 4A shows binding titration curves of the clasping antibodies with the peptide IP assay. Figures 4B, 4C show validation of clasping antibodies in Western blot. SUMO-fusedpeptides (Figure 4B), and whole cell lysates (WCLs) from PDGF-BB-treated NIH 3T3 cells (Figure 4C, top blot) and K562 cells that do not or minimally express PDGFRb (Figure 4C, bottom blot) were blotted with indicated clasping antibodies and control IgGs. Figure 4D shows validation of clasping antibodies in IP-Western. The lysates from NIH 3T3 cells treated with or without PDGF-BB were immunoprecipitated with the indicated clasping antibodies, and the immunoprecipitated samples were subsequently blotted with anti-PDGFRb antibody. The clasping antibodies specifically detected and captured PDGFRb in a phosphorylation-dependent manner. Figures 4E, 4F show characterization of clasping antibodies targeting BCR pY177 in the long-neck scFv-Fc format with the peptide IP assay (Figure 4E) and Western blot using WCL (Figure 4F). The isotype (Figures 4B-D, 4F) composes 4G10 (PTM unit) and a non- binding antibody (in place of an enhancer unit), and consequently has weak affinity to pY. The apparent KD values, calculated from the curve fitting of a 1:1 binding model to the target peptide, are shown (Figures 4A, 4E). The abbreviation "dpY" stands for dephosphorylated tyrosine, indicating that the phosphorylation of pY peptides was removed prior to the experiments. The abbreviation “AP” in Western blot (Figures 4C, 4F) stands for alkaline phosphatase and each lane displaying “+” was treated with AP prior to being blotted with antibodies. The “secondary only” lanes refer to no primary antibody with anti-mouse Fc-HRP (secondary only 1) or with anti-rabbit IgG-HRP (secondary only 2). See Figures 12, 13 for the complete datasets for Western blot.

[0352] Figures 5A-5E show amino acid sequences of antigen peptides and characterization ofclasping Fabs targeting H3K56me3. Figure 5A shows the amino acid sequences of histone peptides (bottom table) and pY peptides (top table) in this study. The residues harboring PTMs are labeled in bold. The lysine residue at the GYKD (SEQ ID NO: 284) or GGKD (SEQ ID NO: 285) tags is biotinylated. Figure 5A discloses SEQ ID NOS 189-199, respectively, in order of columns. Figures 5B, 5C show size-exclusion chromatograms using a TSKgel SuperSW mAb HR column (Figure 5B) and SDS-PAGE profiles (Figure 5C) of purified Fabs. The elution positions of standard proteins (with molecular weights of 670, 158, 44, and 17 kDa, respectively) are indicated by arrows (Figure 5B). Figure 5D shows the binding titration curves of clasping Fabs against the target and off-target peptides with the peptide IP assay. The PTM and enhancer Fabs were co-immobilized on beads. The apparent KDvalues, calculated from the curve fitting of a 1:1 binding model to the target peptide are shown. Sequence specificity (left panels) andmethylation-state specificity (right panels) were assessed. Data shown here are from triplicate measurements. Error bars indicate the s.d. Figure 5E shows CDR sequences of enhancer antibodies. Residues that are randomized in the antibody library but located outside CDRH1 are indicated by an underscore. Figure 5E discloses SEQ ID NOS 287-290, 27, 45, 27, 45, 28, 46, 55, 65, 24, 42, 53, and 62, respectively, in order of columns.

[0353] Figures 6A-6C show linker optimization and binding characterization of claspingantibodies to H3K56me3 in the yeast-display format. Figure 6A shows that the length of the linker shown in the left cartoon was optimized. The right table shows the amino acid sequences of the linkers tested. Figure 6A discloses SEQ ID NOS 31 and 34-35, respectively, in order of appearance. Figure 6B shows binding titration curves of clasping antibodies to H3K56me3 harboring different linker lengths in the yeast display format. The apparent KDvalues were calculated from the curve fitting of a 1:1 binding model. Figure 6C shows specificity test of clasping antibodies to H3K56me3 in the yeast-display format harboring the 22-residue linker (Linker B). The concentrations of the peptides used for A5-3, A5-14, and A5-16 were 30, 10 and 80 nM, respectively. Data shown here are from triplicate measurements. Error bars indicate the s.d.

[0354] Figures 7A-7E show characterization of clasping antibodies in the yeast-displayformat. Figures 7A-7D show the binding characterization of clasping antibodies targeting H3K9me3 (Figure 7A), H3K27me3 (Figures 7B, 7C), and H4K20me3 (Figure 7D). The left panels show the binding titration curves to the target peptides. The apparent KDvalues were calculated from the curve fitting of a 1:1 binding model. The right panels show the specificity test using multiple histone peptides. The highest peptide concentrations used in the binding titration curves were utilized in the specificity test. Data shown here are from triplicate measurements. Error bars indicate the s.d. Figure 7E shows CDR sequences of enhancer antibodies. Residues that were randomized in the antibody library but located outside CDRH1 are indicated by an underscore. Figure 7E discloses SEQ ID NOS 291, 292, 291, 288, 293, 293, 293, 294, 293, 295, 293, 293, 296, 290, 293, 75, 75, 75, 27, 94, 94, 94, 94, 94, 45, 94, 45, 45, 45, 45, 76, 76, 85, 76, 95, 95, 95, 95, 95, 95, 95, 125, 125, 125, 132, 72, 79, 83, 88, 92, 104, 72, 72, 113, 72, 118, 123, 123, 123, and 123, respectively, in order of columns.

[0355] Figures 8A-8D show characterization of commercial recombinant antibodies and anti-H3K27me3 clasping antibodies with the peptide IP assay. Figure 8A shows binding titration ofcommercially available recombinant antibodies to H3K27me3 (top) and H4K20me3 (bottom). Figures 8B, 8C show size-exclusion chromatograms using a TSKgel SuperSW mAb HR column (Figure 8B) and SDS-PAGE profiles (Figure 8C) of purified Fabs. The elution positions of standard proteins (with molecular weights of 670, 158, 44, and 17 kDa, respectively) are indicated by arrows (Figure 8B). Figure 8D shows binding titration of clasping Fabs. The PTM and enhancer Fabs were co-immobilized on beads. The apparent KD values calculated from the curve fitting of a 1:1 binding model to the target peptide are shown. Data shown here were from triplicate measurements. Error bars indicate the s.d.

[0356] Figures 9A-9D show performance comparison of the clasping antibody and the widely-used commercial antibody in native ICeChIP. Figure 9A shows scheme of ICeChIP using internal nucleosome standards to calibrate native ChIP. Figure 9B shows cartoon representation of the most relevant barcoded nucleosomes. Figure 9C shows scatter plots of input and IP reads for each member captured for the indicated barcoded nucleosome standards (symmetric H3K4me3, symmetric H3K27me3, symmetric cis-H3K4me3 / H3K27me3 and asymmetric trans- H3K4me3 / H3K27me3). Linear regressions and indicated R2statistics for the fitting are displayed. Bottom: widely-used H3K27me3 monoclonal antibody (C36B11), Top: 3C2-H2 clasping Fab. Figure 9D shows another representative locus on chromosome 3 displaying apparent H3K27me3 histone modification density (HMD) with antibodies.

[0357] Figures 10A-10E show characterization of anti-H3K27me3 long-neck scFv-Fcantibodies and SNAP-ChIP analysis of the commercial recombinant antibody. Figures 10A, 10B show size-exclusion chromatograms using a Superdex 200 increase 5 / 150 GL column (Figure 10A) and SDS-PAGE profiles (Figure 10B) of purified long-neck scFv-Fc antibodies. The elution positions of standard proteins (with molecular weights of 670, 158, 44, and 17 kDa, respectively) are indicated by arrows (Figure 10A). Figure 10C shows binding titration curves of long-neck scFv-Fc antibodies against the H3K27me3S28phos peptide with the peptide IP assay. The apparent KD values calculated from the curve fitting of a 1:1 binding model are shown. Data shown here were from triplicate measurements. Error bars indicate the s.d. Figure 10D shows the uncropped western blot, related to Figure 3D. Whole-cell lysate of K562 cells was blotted with the indicated clasping antibodies at three different concentrations (30, 10 and 3.3 nM, respectively). The isotype composes 4-5 (PTM unit) and a non-binding antibody (in replacement of an enhancer unit), and consequently has weak affinity to Kme3. The “secondaryonly” lanes refer to no primary antibody with anti-mouse Fc-HRP (secondary only 1) or with anti-rabbit IgG-HRP (secondary only 2). The arrow indicates the location corresponding to histone H3. Data shown here were representative of ≥2 equivalent experiments. Figure 10E shows native SNAP-ChIP analysis of recombinant anti-H3K27me3 antibody (AB_2793791). The specificity (percentage of off-target immunoprecipitation relative to the on-target, bottom panel) and enrichment (percentage of nucleosomes recovered after immunoprecipitation relative to input, top panel) assessed by qPCR were shown. Data shown here were from triplicate measurements. Error bars indicate the s.d.

[0358] Figures 11A-11B show binding characterization of 4G10, anti-pan-pY antibody, in theFab and yeast-displayed formats. Figure 11A shows the binding analysis of 4G10 in the Fab format with the peptide IP assay. The SUMO-fused peptides harboring phosphorylated tyrosine were used. The apparent KD values were calculated from the curve fitting of a 1:1 binding model. Figure 11B shows the binding analysis of 4G10 scFv in the yeast-display format. The cartoon on the top depicts the extension of the linker between 4G10 scFv and Aga2 protein. The binding of 4G10 scFv in the domain order of heavy and light variable chains (middle panel) and of light and heavy variable chains (bottom panel) with different linker lengths was tested against indicated peptides at 500 nM concentration. Extending the linker length restored the binding of 4G10 scFv. The abbreviation "dpY" stands for dephosphorylated tyrosine, indicating that the phosphorylation of pY peptides was removed prior to the experiments. Data shown here were from triplicate measurements. Error bars indicate the s.d.

[0359] Figures 12A-12F show characterization of clasping antibodies targeting the PDGFRbpY716 peptide. Figure 12A shows the binding analysis of clasping antibodies to PDGFRb pY716 in the yeast-display format. Figures 12B, 12C show size-exclusion chromatograms using a Superdex 200 increase 5 / 150 GL column (Figure 12B) and SDS-PAGE profiles (Figure 12C) of purified long-neck scFv-Fc antibodies. The elution positions of standard proteins (with molecular weights of 670, 158, 44, and 17 kDa, respectively) are indicated by arrows (Figure 12B). The 4G10 scFv was used as the PTM unit. Figure 12D shows binding titration curves of long-neck scFv-Fc antibodies against the target and off-target peptides with the peptide IP assay. The abbreviation of “dpY” denotes dephosphorylated tyrosine, indicating that the phosphorylation of pY peptides was removed prior to the experiments. The apparent KDvalues were calculated from the curve fitting of a 1:1 binding model. Data shown here were fromtriplicate measurements. Error bars indicate the s.d. Figure 12E shows CDR sequences of enhancer antibodies for PDGFRb pY716. Residues that are randomized in the antibody library but located outside CDRH1 are indicated by an underscore. Figure 12E discloses SEQ ID NOS 297, 298, 297, 297, 145, 145, 157, 157, 146, 153, 146, 153, 72, 72, 72, 161, respectively, in order of columns. Figure 12F shows the uncropped western blots, related to Figure 4C. The whole cell lysates (WCLs) from NIH 3T3 cells treated with PDGF-BB (bottom blot) and from K562 cells (top blot) were blotted with indicated clasping antibodies in the long-neck scFv-Fc format or control IgGs. The isotype composes 4G10 (PTM unit) and a non-binding antibody (in place of an enhancer unit), and consequently has weak affinity to pY. The abbreviation “AP” stands for alkaline phosphatase and each lane displaying “+” was treated with AP prior to being blotted with antibodies. The “secondary only” lanes refer to no primary antibody with anti-mouse Fc- HRP (secondary only 1) and with anti-rabbit-IgG HRP (secondary only 2). The arrows indicate the locations corresponding to PDGFRb and vinculin. The data shown are representative of ≥2 equivalent experiments.

[0360] Figures 13A-13F show characterization of clasping antibodies targeting the BCRpY177 peptide. Figure 13A shows the binding analysis of clasping antibodies to BCR pY177 in the yeast-display format. Figures 13B, 13C show size-exclusion chromatograms using a Superdex 200 increase 5 / 150 GL column (Figure 13B) and SDS-PAGE profiles (Figure 13C) of purified long-neck scFv-Fc antibodies. The elution positions of standard proteins (with molecular weights of 670, 158, 44, and 17 kDa, respectively) are indicated by arrows (Figure 13B). The 4G10 scFv was used as the PTM unit. Figure 13D shows binding titration curves of long-neck scFv-Fc antibodies against the target and off-target peptides with the peptide IP assay. The abbreviation of “dpY” denotes dephosphorylated tyrosine. The apparent KD values were calculated from the curve fitting of a 1:1 binding model. Data shown here were from triplicate measurements. Error bars indicate the s.d. Figure 13E shows CDR sequences of enhancer antibodies for BCR pY177. Residues that are randomized in the antibody library but located outside CDRH1 are indicated by an underscore. Figure 13E discloses SEQ ID NOS 299, 300, 301, 299, 169, 169, 169, 169, 170, 170, 170, 170, 166, 166, 177, and 181, respectively, in order of columns. Figure 13F shows the uncropped western blots, related to Figure 4F. The whole cell lysate (WCL) from K562 cells was blotted with indicated clasping antibodies in the long- neck scFv-Fc format or control IgGs. The isotype composes 4G10 (PTM unit) and a non-bindingantibody (in place of an enhancer unit), and consequently has weak affinity to pY. The abbreviation “AP” stands for alkaline phosphatase and each lane displaying “+” was treated with AP prior to being blotted with antibodies. The “secondary only” lanes refer to no primary antibody with anti-mouse Fc-HRP (secondary only 1) or with anti-rabbit IgG-HRP (secondary only 2). The arrows indicate locations corresponding to BCR-ABL, BCR or vinculin. The data shown are representative of ≥2 equivalent experiments. DETAILED DESCRIPTION

[0361] Post-translational modifications (PTMs) are chemical modifications of proteins that areimportant in many cellular functions. Dysregulation of PTMs contributes to many diseases including cancer. Antibodies to PTMs are a central component in analyzing PTMs. However, many available antibodies have severe shortcomings, including low specificity, low affinity, and lot-to-lot variation, which could lead researchers to incorrect conclusions and contribute to a lack of reproducibility in research results. To solve this antibody problem, the present inventors have developed a technology platform to efficiently generate high-performance recombinant antibodies to PTMs that are molecularly defined and renewable.

[0362] This technology platform is built on an unconventional binding mode of anti-PTMantibodies, antigen clasping, where two antigen binding sites cooperatively clasp a single antigen, creating extensive interactions with the antigen and leading to high selectivity and potency. Antibody fragments such as an antigen-binding fragment (Fab) or a variable fragment (Fv) contain a single antigen-binding site, and the 1:1 stoichiometry of the antibody-antigen recognition is a highly conserved recognition mode among numerous known antibodies. However, antigen clasping comprises two antigen-binding sites that cooperatively sandwich one single antigen by forming a head-to-head homodimer (21). Compared with the conventional 1:1 antibody-antigen recognition, the antigen clasping binding mode doubles the size of the antigen recognition interface, contributing to high affinity and exquisite specificity to both PTM and peptide sequence. Thus, antigen clasping is a suited binding mode for the specific recognition of PTMs in a sequence-specific manner compared to the conventional binding mode of antibodies.

[0363] Antigen clasping serendipitously emerged during the iterative optimization process.Indeed, other anti-histone methylation antibodies exhibit no antigen clasping (12, 21). Although the emergence of antigen clasping demonstrates the power of directed evolution, thedevelopment process required multiple rounds of mutagenesis and screening. The binding mode of antigen clasping is conceptually similar to that of molecules termed affinity clamps, where the clamshell architecture was intentionally designed (22-24). An affinity clamp consists of a naturally occurring modular binding domain, such as PDZ and SH2 domains, and a monobody that is engineered to recognize the target peptide presented by the modular binding domain (22- 24). This concept has successfully been applied to peptides harboring phospho-tyrosine or the C- terminal carboxyl group (22, 24). However, the inherent peptide motif specificity of the natural domains limits the applications of affinity clamps to a broad range of peptides. In addition, the development of affinity clamps often requires extensive modifications of a modular binding domain, e.g., circular permutation (22), which may not be tolerated by a domain of interest.

[0364] The technology platform disclosed herein generates clasping antibodies with twodistinct binding units, resulting in the efficient generation of antibodies to a diverse set of trimethylated histone H3 and phosphotyrosine antigens with high levels of specificity and affinity without extensive optimization steps. Using this technology, the present inventors have generated high-performance antibodies to histone H3 trimethylated Lys9 (H3K9me3), histone H3 trimethylated Lys27 (H3K27me3), histone H3 trimethylated Lys56 (H3K56me3), histone H4 trimethylated Lys20 (H4K20me3), phosphorylated PDGFRb (pY716) and phosphorylated BCR177 (pY177). The ability to generate various high-performance antibodies suggests the broad applicability of this technology platform to producing next-generation antibodies to a variety of PTMs with diverse sequence space. Further, the generated antibodies are recombinant antibodies, and thus they have minimal lot-to-lot variation. Their renewability and well-validated features eliminate a major burden in obtaining reproducible results and an extra effort for researchers to validate antibodies by themselves. Definitions

[0365] The term “antibody” refers to an immunoglobulin molecule capable of specific bindingto a target, such as a carbohydrate, polynucleotide, lipid, polypeptide, protein, etc., through at least one antigen recognition site, located in the variable region(s) of the immunoglobulin molecule. As used herein, the term “antibody”, e.g., a clasping antibody, encompasses not only intact (e.g., full-length) polyclonal or monoclonal antibodies, but also combinations of antibodies, antigen-binding fragments thereof (such as Fab, Fab', F(ab')2, Fv), single chain (scFv), mutants thereof, fusion proteins comprising an antibody portion, a multispecificantibody, an antibody conjugate, humanized antibodies, chimeric antibodies, diabodies, nanobodies, linear antibodies, single chain antibodies, multi-specific antibodies (e.g., bispecific antibodies) and any other modified configuration of the immunoglobulin molecule that comprises an antigen recognition site of the required specificity, including glycosylation variants of antibodies, amino acid sequence variants of antibodies, and covalently modified antibodies. An antibody, e.g., a clasping antibody, includes an antibody of any class, such as IgD, IgE, IgG, IgA, or IgM (or sub-class thereof), and the antibody need not be of any particular class. Depending on the antibody amino acid sequence of the constant domain of its heavy chains, immunoglobulins can be assigned to different classes. There are five major classes of immunoglobulins: IgA, IgD, IgE, IgG, and IgM, and several of these may be further divided into subclasses (isotypes), e.g., IgG1, IgG2, IgG3, IgG4, IgA1 and IgA2. The heavy-chain constant domains that correspond to the different classes of immunoglobulins are called alpha, delta, epsilon, gamma, and mu, respectively. The subunit structures and three-dimensional configurations of different classes of immunoglobulins are well known.

[0366] A typical antibody molecule comprises a heavy chain variable region (VH) and a lightchain variable region (VL), which are usually involved in antigen binding. The VH and VL regions can be further subdivided into regions of hypervariability, also known as “complementarity determining regions” (“CDR”), interspersed with regions that are more conserved, which are known as “framework regions” (“FR”). Each VH and VL is typically composed of three CDRs and four FRs, arranged from amino-terminus to carboxy-terminus in the following order: FR1, CDR1, FR2, CDR2, FR3, CDR3, FR4. The extent of the framework region and CDRs can be precisely identified using methodology known in the art, for example, by the Kabat definition, the Chothia definition, the AbM definition, the EU definition, the “Contact” numbering scheme, the “IMGT” numbering scheme, the “AHo” numbering scheme, and / or the contact definition, all of which are well known in the art. (See, e.g., Kabat, E.A., et al. (1991) Sequences of Proteins of Immunological Interest, Fifth Edition, U.S. Department of Health and Human Services, NIH Publication No.91-3242; Chothia et al., (1989) Nature 342:877; Chothia, C. et al. (1987) J. Mol. Biol.196:901-917; Al-lazikani et al (1997) J. Molec. Biol.273:927-948; Edelman et al., Proc Natl Acad Sci U S A.1969, 63(1):78-85; Almagro, J. Mol. Recognit.17:132-143 (2004); MacCallum et al., J. Mol. Biol.262:732-745 (1996); LefrancM P et al., Dev Comp Immunol, 2003 January; 27(1):55-77; and Honegger A and Pluckthun A, J Mol Biol, 2001, 309(3):657-70. See also hgmp.mrc.ac.uk and bioinf.org.uk / abs).

[0367] In some embodiments, the clasping antibody described herein is a full-length antibody,which contains two heavy chains and two light chains, each including a variable domain and a constant domain. Alternatively, the clasping antibody can be an antigen-binding fragment of a full-length antibody. The clasping antibody can be a combination of antibodies, an antibody fusion molecule, a multispecific antibody, or an antibody conjugate. Examples of binding fragments encompassed within the term “antigen-binding fragment” of a full length antibody include (i) a Fab fragment, a monovalent fragment consisting of the VL, VH, CL and CH1 domains; (ii) a F(ab')2fragment, a bivalent fragment including two Fab fragments linked by a disulfide bridge at the hinge region; (iii) a Fd fragment consisting of the VHand CH1 domains; (iv) a Fv fragment consisting of the VL and VH domains of a single arm of an antibody, (v) a dAb fragment (Ward et al., (1989) Nature 341:544-546), which consists of a VH domain; and (vi) an isolated complementarity determining region (CDR) that retains functionality. Furthermore, although the two domains of the Fv fragment, VL and VH, are coded for by separate genes, they can be joined, using recombinant methods, by a synthetic linker that enables them to be made as a single protein chain in which the VLand VHregions pair to form monovalent molecules known as single chain Fv (scFv). See e.g., Bird et al. (1988) Science 242:423-426; and Huston et al. (1988) Proc. Natl. Acad. Sci. USA 85:5879-5883.

[0368] Any of the antibodies described herein, e.g., clasping antibody, can be eithermonoclonal or polyclonal. A “monoclonal antibody” refers to a homogenous antibody population and a “polyclonal antibody” refers to a heterogeneous antibody population. These two terms do not limit the source of an antibody or the manner in which it is made.

[0369] As used herein “specifically binds”, “specific binding”, “specifically recognizes” or“specifically recognition” refers to the ability of the antibodies or antigen-binding fragments of the disclosure to bind to a predetermined antigen (e.g., an epitope harboring one or more PTMs) with a dissociation constant (KD) of about 1×10−6M or less, for example about 1×10−7M or less, about 1×10−8M or less, about 1×10−9M or less, about 1×10−10M or less, about 1×10−11M or less, about 1×10−12M or less, or about 1×10−13M or less. Typically, the antibody or antigen-binding fragment binds to an antigen (e.g., an epitope harboring one or more PTMs) with a KDthat is atleast ten-fold less than its KDfor a nonspecific antigen (for example BSA or casein) as measured by e.g., surface plasmon resonance using for example a Proteon Instrument (BioRad).

[0370] “Isolated” means a biological component (such as a nucleic acid, peptide or protein)has been substantially separated, produced apart from, or purified away from other biological components of the organism in which the component naturally occurs, i.e., other chromosomal and extrachromosomal DNA and RNA, and proteins. Nucleic acids, peptides and proteins that have been “isolated” thus include nucleic acids and proteins purified by standard purification methods. “Isolated” nucleic acids, peptides and proteins can be part of a composition and still be isolated if such composition is not part of the native environment of the nucleic acid, peptide, or protein. The term also embraces nucleic acids, peptides and proteins prepared by recombinant expression in a host cell as well as chemically synthesized nucleic acids in the polynucleotides that encode for the antibody or antigen-binding fragment described herein. An “isolated” antibody or antigen-binding fragment, as used herein, is intended to refer to an antibody or antigen-binding fragment which is substantially free of other antibodies or antigen-binding fragments having different antigenic specificities (for instance, an isolated antibody that specifically binds to an intended antigen (e.g., an epitope harboring one or more PTMs) is substantially free of antibodies that specifically bind antigens other than the intended antigen).

[0371] The term “polynucleotide” as referred to herein means a polymeric form of nucleotidesof at least 10 bases in length, either ribonucleotides or deoxyribonucleotides or a modified form of either type of nucleotide. The term includes single and double stranded forms.

[0372] The term “isolated polynucleotide” as used herein means a polynucleotide of genomic,cDNA, or synthetic origin or some combination thereof, which by virtue of its origin or source of derivation, the “isolated polynucleotide” has one to three of the following: (1) is not associated with all or a portion of a polynucleotides with which the “isolated polynucleotide” is found in nature, (2) is operably linked to a polynucleotide to which it is not linked in nature, or (3) does not occur in nature as part of a larger sequence.

[0373] “Operably linked” sequences include both expression control sequences that arecontiguous with the gene of interest and expression control sequences that act in trans or at a distance to control the gene of interest. The term “expression control sequence” as used herein means polynucleotide sequences that are necessary to effect the expression and processing of coding sequences to which they are ligated. Expression control sequences include appropriatetranscription initiation, termination, promoter and enhancer sequences; efficient RNA processing signals such as splicing and polyadenylation signals; sequences that stabilize cytoplasmic mRNA; sequences that enhance translation efficiency (i.e., Kozak consensus sequence); sequences that enhance protein stability; and when desired, sequences that enhance protein secretion. The nature of such control sequences differs depending upon the host organism; in prokaryotes, such control sequences generally include promoter, ribosomal binding site, and transcription termination sequence; in eukaryotes, generally, such control sequences include promoters and transcription termination sequence. The term “control sequences” is intended to include, at a minimum, all components whose presence is essential for expression and processing, and can also include additional components whose presence is advantageous, for example, leader sequences and fusion partner sequences.

[0374] The term “vector”, as used herein, means a vehicle capable of transporting a nucleicacid into a host cell. In some embodiments, the vector is a plasmid, i.e., a circular double stranded DNA loop into which additional DNA segments may be ligated. In some embodiments, the vector is a viral vector, wherein additional DNA segments may be ligated into the viral genome. In some embodiments, the vectors are capable of autonomous replication in a host cell into which they are introduced (e.g., bacterial vectors having a bacterial origin of replication and episomal mammalian vectors). In other embodiments, the vectors (e.g., non-episomal mammalian vectors) can be integrated into the genome of a host cell upon introduction into the host cell, and thereby are replicated along with the host genome. Moreover, certain vectors are capable of directing the expression of genes to which they are operatively linked. Such vectors are referred to herein as “recombinant expression vectors” (or simply, “expression vectors”).

[0375] The term “promoter” as used herein is defined as a DNA sequence recognized by thesynthetic machinery of the cell, or introduced synthetic machinery, required to initiate the specific transcription of a polynucleotide sequence. As used herein, the term “regulatory sequence” means a nucleic acid sequence which can regulate expression of a gene product operably linked to the regulatory sequence. In some instances, this sequence may be the core promoter sequence and in other instances, this sequence may also include an enhancer sequence and other regulatory elements which are required for expression of the gene product. The promoter or regulatory sequence may, for example, be one which expresses the gene product in a tissue specific manner.

[0376] The term “recombinant host cell” (or simply “host cell”), as used herein, means a cellinto which an exogenous nucleic acid and / or recombinant vector has been introduced. It should be understood that “recombinant host cell” and “host cell” mean not only the particular subject cell but also the progeny of such a cell. Because certain modifications may occur in succeeding generations due to either mutation or environmental influences, such progeny may not, in fact, be identical to the parent cell, but are still included within the scope of the term “host cell” as used herein.

[0377] The term “percent sequence identity” means a ratio, expressed as a percent of thenumber of identical residues over the total number of residues compared.

[0378] Sequence identity for nucleic acid sequences may be analyzed over a stretch of at leastabout nine nucleotides, usually at least about 18 nucleotides, more usually at least about 24 nucleotides, typically at least about 28 nucleotides, more typically at least about 32 nucleotides, and preferably at least about 36, 48 or more nucleotides. There are a number of different algorithms known in the art which can be used to measure nucleotide sequence identity. For instance, polynucleotide sequences can be compared using FASTA, Gap or Bestfit, which are programs in Wisconsin Package Version 10.0, Genetics Computer Group (GCG), Madison, Wis. FASTA, which includes, e.g., the programs FASTA2 and FASTA3, provides alignments and percent sequence identity of the regions of the best overlap between the query and search sequences (Pearson, Methods Enzymol.183:63-98 (1990); Pearson, Methods Mol. Biol.132:185- 219 (2000); Pearson, Methods Enzymol.266:227-258 (1996); Pearson, J. Mol. Biol.276:71-84 (1998); herein incorporated by reference). Unless otherwise specified, default parameters for a particular program or algorithm are used. For instance, percent sequence identity between nucleic acid sequences can be determined using FASTA with its default parameters (a word size of 6 and the NOPAM factor for the scoring matrix) or using Gap with its default parameters as provided in GCG Version 6.1, herein incorporated by reference.

[0379] A reference to a nucleotide sequence encompasses its complement unless otherwisespecified. Thus, a reference to a nucleic acid having a particular sequence should be understood to encompass its complementary strand, with its complementary sequence.

[0380] Sequence identity for polypeptides, is typically measured using sequence analysissoftware. Protein analysis software matches sequences using measures of similarity assigned to various substitutions, deletions and other modifications, including conservative amino acidsubstitutions. For instance, GCG contains programs such as “Gap” and “Bestfit” which can be used with default parameters, as specified with the programs, to determine sequence homology or sequence identity between closely related polypeptides, such as homologous polypeptides from different species of organisms or between a wild-type protein and a mutein thereof. See, e.g., GCG Version 6.1. Polypeptide sequences also can be compared using FASTA using default or recommended parameters, see GCG Version 6.1. (University of Wisconsin Wis.) FASTA (e.g., FASTA2 and FASTA3) provides alignments and percent sequence identity of the regions of the best overlap between the query and search sequences (Pearson, Methods Enzymol.183:63- 98 (1990); Pearson, Methods Mol. Biol.132:185-219 (2000)). Another preferred algorithm when comparing a sequence of the invention to a database containing a large number of sequences from different organisms is the computer program BLAST, especially blastp or tblastn, using default parameters, as supplied with the programs. See, e.g., Altschul et al., J. Mol. Biol. 215:403-410 (1990); Altschul et al., Nucleic Acids Res.25:3389-402 (1997).

[0381] The length of polypeptide sequences compared for homology will generally be at leastabout 16 amino acid residues, usually at least about 20 residues, more usually at least about 24 residues, typically at least about 28 residues, and preferably more than about 35 residues. When searching a database containing sequences from a large number of different organisms, it is preferable to compare amino acid sequences.

[0382] The term “substantial similarity” or “substantial sequence similarity,” when referring toa nucleic acid or fragment thereof, means that when optimally aligned with appropriate nucleotide insertions or deletions with another nucleic acid (or its complementary strand), there is nucleotide sequence identity in at least about 85%, preferably at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% of the nucleotide bases, as measured by any well- known algorithm of sequence identity, such as FASTA, BLAST or Gap, as discussed above.

[0383] As applied to polypeptides, the term “substantial identity” means that two peptidesequences, when optimally aligned, such as by the programs GAP or BESTFIT using default gap weights, as supplied with the programs, share at least 70%, 75%, 80% or 85% sequence identity, preferably at least 90%, 91%, 92%, 93%, 94% 95%, 96%, 97%, 98% or 99% sequence identity. In certain embodiments, residue positions that are not identical differ by conservative amino acid substitutions.

[0384] A “conservative amino acid substitution” is one in which an amino acid residue issubstituted by another amino acid residue having a side chain R group with similar chemical properties (e.g., charge or hydrophobicity). In general, a conservative amino acid substitution will not substantially change the functional properties of a protein. In cases where two or more amino acid sequences differ from each other by conservative substitutions, the percent sequence identity may be adjusted upwards to correct for the conservative nature of the substitution. Means for making this adjustment are well-known to those of skill in the art. See, e.g., Pearson, Methods Mol. Biol.243:307-31 (1994). Examples of groups of amino acids that have side chains with similar chemical properties include 1) aliphatic side chains: glycine, alanine, valine, leucine, and isoleucine; 2) aliphatic-hydroxyl side chains: serine and threonine; 3) amide-containing side chains: asparagine and glutamine; 4) aromatic side chains: phenylalanine, tyrosine, and tryptophan; 5) basic side chains: lysine, arginine, and histidine; 6) acidic side chains: aspartic acid and glutamic acid; and 7) sulfur-containing side chains: cysteine and methionine. Conservative amino acids substitution groups are: valine-leucine-isoleucine, phenylalanine- tyrosine, lysine-arginine, alanine-valine, glutamate-aspartate, and asparagine-glutamine.

[0385] Alternatively, a conservative substitution or replacement, as the terms are usedinterchangeably herein, is any change having a positive value in the PAM250 log-likelihood matrix disclosed in Gonnet et al., Science 256:1443-45 (1992), herein incorporated by reference. A “moderately conservative” replacement is any change having a nonnegative value in the PAM250 log-likelihood matrix.

[0386] The term “cytotoxic agent” refers to a compound that can cause harm, disturbances, ordeath to a cell.

[0387] The terms “treat” or “treatment” of a state, disorder or condition include: (1)preventing, delaying, or reducing the incidence and / or likelihood of the appearance of at least one clinical or sub-clinical symptom of the state, disorder or condition developing in a subject that may be afflicted with or predisposed to the state, disorder or condition but does not yet experience or display clinical or subclinical symptoms of the state, disorder or condition; or (2) inhibiting the state, disorder or condition, i.e., arresting, reducing or delaying the development of the disease or a relapse thereof (in case of maintenance treatment) or at least one clinical or sub- clinical symptom thereof; or (3) relieving the disease, i.e., causing regression of the state, disorder or condition or at least one of its clinical or sub-clinical symptoms. The benefit to asubject to be treated is either statistically significant or at least perceptible to the patient or to the physician.

[0388] As used herein the term “therapeutically effective” applied to dose or amount refers tothat quantity of a compound or pharmaceutical composition that is sufficient to result in a desired activity upon administration to an animal in need thereof. Within the context of the present invention, the term “therapeutically effective” refers to that quantity of a compound or pharmaceutical composition that is sufficient to reduce or eliminate at least one symptom of a cancer, inflammation, or related disorder. Note that when a combination of active ingredients is administered the effective amount of the combination may or may not include amounts of each ingredient that would have been effective if administered individually.

[0389] The phrase “therapeutically effective amount” as used herein, means an amountsufficient to achieve the desired effect for which it is administered. The subject can be from any suitable species, such as mammalian or eukaryotic subjects (e.g., human subject or non-human mammalian subject). A mammal can be, but is not limited to, a non-human mammal, a hamster, a rodent, a mouse, a human, or a rat. Non-human mammals include, but are not limited to, non- human primates, for example, monkeys and apes. The term “non-human” means excluding humans.

[0390] As used herein, the phrase “pharmaceutically acceptable” refers to molecular entitiesand compositions that are generally regarded as physiologically tolerable.

[0391] As used herein, the term “combination” of a compound or a composition, and at least asecond pharmaceutically active ingredient means at least two, but any desired combination of compound or composition can be delivered simultaneously or sequentially.

[0392] The terms “patient”, “individual”, “subject”, and “animal” are used interchangeablyherein and refer to mammals, including, without limitation, human and veterinary animals (e.g., cats, dogs, cows, horses, goats, sheep, pigs, etc.) and experimental animal models. In a preferred embodiment, the subject is a human.

[0393] As used herein, the term “healthy subject” refers to a subject that is without knowninfections or autoimmune disorders by using conventional diagnostic methods. In certain embodiments, a healthy subject is a subject without a known first degree relative with an autoimmune disorder. In certain embodiments, a matched healthy subject is matched by age, gender, and / or ethnicity.

[0394] The term “carrier” refers to a diluent, adjuvant, excipient, or vehicle with which thecompound is administered. Such pharmaceutical carriers can be sterile liquids, such as water and oils, including those of petroleum, animal, vegetable or synthetic origin, such as peanut oil, soybean oil, mineral oil, sesame oil and the like. Water or aqueous solution saline solutions and aqueous dextrose and glycerol solutions are preferably employed as carriers, particularly for injectable solutions. Alternatively, the carrier can be a solid dosage form carrier, including but not limited to one or more of a binder (for compressed pills), a glidant, an encapsulating agent, a flavorant, and a colorant. Suitable pharmaceutical carriers are described in “Remington’s Pharmaceutical Sciences” by E.W. Martin.

[0395] The term “in vitro” is meant to include artificial environments and includes reactionsand / or processes that occur within said artificial environment (e.g., an isolated cell or cell line or a test tube). The term “in vivo” is meant to includes natural environments (e.g., a body, an organism, or a cell) and includes reactions and / or processes that occur within said natural environment. The term “ex vivo” is meant to include cells that have been removed (e.g., from a body of an individual) and reactions and / or processes that occur within said cells.

[0396] The term “disordered region” is defined as a region of a protein that lacks a fixed orordered tertiary structure.

[0397] The term “about” or “approximately” means within a statistically meaningful range of avalue. Such a range can be within an order of magnitude, preferably within 50%, more preferably within 20%, still more preferably within 10%, and even more preferably within 5% of a given value or range. The allowable variation encompassed by the term “about” or “approximately” depends on the particular system under study, and can be readily appreciated by one of ordinary skill in the art.

[0398] The terms “a,” “an,” and “the” do not denote a limitation of quantity, but rather denotethe presence of “at least one” of the referenced item.

[0399] The practice of the present invention employs, unless otherwise indicated, conventionaltechniques of statistical analysis, molecular biology (including recombinant techniques), microbiology, cell biology, and biochemistry, which are within the skill of the art. Such tools and techniques are described in detail in e.g., Sambrook et al. (2001) Molecular Cloning: A Laboratory Manual.3rd ed. Cold Spring Harbor Laboratory Press: Cold Spring Harbor, New York; Ausubel et al. eds. (2005) Current Protocols in Molecular Biology. John Wiley and Sons,Inc.: Hoboken, NJ; Bonifacino et al. eds. (2005) Current Protocols in Cell Biology. John Wiley and Sons, Inc.: Hoboken, NJ; Coligan et al. eds. (2005) Current Protocols in Immunology, John Wiley and Sons, Inc.: Hoboken, NJ; Coico et al. eds. (2005) Current Protocols in Microbiology, John Wiley and Sons, Inc.: Hoboken, NJ; Coligan et al. eds. (2005) Current Protocols in Protein Science, John Wiley and Sons, Inc.: Hoboken, NJ; and Enna et al. eds. (2005) Current Protocols in Pharmacology, John Wiley and Sons, Inc.: Hoboken, NJ. Additional techniques are explained, e.g., in U.S. Patent No.7,912,698 and U.S. Patent Appl. Pub. Nos.2011 / 0202322 and 2011 / 0307437. Antibodies and Combinations of Antibodies and Antigen-Binding Fragments

[0400] The present disclosure provides antibodies or combinations of antibodies or antigen-binding fragments thereof, that comprise two binding units binding a target protein, one binding unit binding to a first epitope comprising a post-translational modification (PTM) and the other binding unit binding a second epitope not comprising the PTM.

[0401] In one aspect, provided herein is an antibody or combination of antibodies or antigen-binding fragment(s) thereof, comprising: (i) a first binding unit (B1) that specifically binds to a first epitope of a target protein, wherein the first epitope includes an amino acid residue harboring one or more of a post-translational modification (PTM); and / or (ii) a second binding unit (B2) that specifically binds to both the first binding unit (B1) and a second epitope of the target protein, wherein the second epitope does not include the PTM.

[0402] In some embodiments, the antibody or combination of antibodies or antigen-bindingfragment(s) thereof comprise (i) a first binding unit (B1) that specifically binds to a first epitope of a target protein, wherein the first epitope includes an amino acid residue harboring one or more of a post-translational modification (PTM); and (ii) a second binding unit (B2) that specifically binds to both the first binding unit (B1) and a second epitope of the target protein, wherein the second epitope does not include the PTM.

[0403] In some embodiments, the PTM is selected from methylation, phosphorylation,acetylation, ubiquitination, glycosylation, formylation, propinylation, butyrylation, crotonylation, benzoylation, 2-hydroxyisobutyrylation, hydroxybutyrylation, lactylation, malonylation, succinylation, glutarylation, hydroxylation, sumoylation, ufmylation, biotinylation, serotonylation, dopaminylation, isomerization, myristoylation, sulfation, nitrosylation, ADP- ribosylation, prenylation, palmitoylation, deamidation, and proteolytic cleavage.

[0404] In some embodiments, the PTM is methylation or phosphorylation.

[0405] In some embodiments, the PTM is comprised within a flexible, disordered region of thetarget protein that does not form a fixed three-dimensional (3D) structure.

[0406] In some embodiments, the target protein is a histone protein, a platelet-derived growthfactor receptor beta (PDGFRb) protein, a breakpoint cluster region (BCR) protein, a protein tyrosine phosphatase (PTPN11) protein, or a fibroblast growth factor receptor substrate 2 (FRS2) protein.

[0407] In some embodiments, the target protein is a histone protein, or a fragment thereof.

[0408] In some embodiments, the histone protein is a histone H3 protein, or fragment thereof,or a histone H4 protein, or fragment thereof.

[0409] In some embodiments, the histone protein is a histone H3 protein, or fragment thereof.

[0410] In some embodiments, the histone protein is a histone H4 protein, or fragment thereof.

[0411] In some embodiments, the first epitope includes a lysine (K) residue that is methylatedone or more times.

[0412] In some embodiments, the lysine (K) residue is trimethylated.

[0413] In some embodiments, the lysine (K) residue is positioned at amino acid position 9, 27,or 56 of the histone H3 protein, or a fragment thereof.

[0414] In some embodiments, the lysine (K) residue is positioned at amino acid position 20 ofthe histone H4 protein, or a fragment thereof.

[0415] In some embodiments, B1 comprises: a) a heavy chain complementarity determiningregion 1 (CDR1), a heavy chain CDR2, a heavy chain CDR3 of a heavy chain variable region (VH) comprising the amino acid sequence of SEQ ID NO: 6; and / or a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a light chain variable region (VL) comprising the amino acid sequence of SEQ ID NO: 1; or b) a heavy chain complementarity determining region 1 (CDR1), a heavy chain CDR2, a heavy chain CDR3 of a heavy chain variable region (VH) comprising the amino acid sequence of SEQ ID NO: 6; and / or a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a light chain variable region (VL) comprising the amino acid sequence of SEQ ID NO: 2.

[0416] In some embodiments, B1 comprises a heavy chain CDR1 comprising the amino acidsequence of SEQ ID NO: 7, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 8, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 9.

[0417] In some embodiments, B1 comprises a light chain CDR1 comprising the amino acidsequence of SEQ ID NO: 3, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 4, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 5.

[0418] In some embodiments, B1 comprises a heavy chain CDR1 comprising the amino acidsequence of SEQ ID NO: 7, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 8, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 9; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 3, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 4, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 5.

[0419] In some embodiments, B1 comprises a VH comprising an amino acid sequence of SEQID NO: 6, and a VL comprising an amino acid sequence of SEQ ID NO: 1 or 2.

[0420] In some embodiments, B2 comprises a heavy chain complementarity determiningregion 1 (CDR1), a heavy chain CDR2, a heavy chain CDR3 of a heavy chain variable region (VH) comprising the amino acid sequence of SEQ ID NO: 25, 43, 54, 63, 73, 80, 84, 89, 93, 108, 115, 124, 127, 129, or 131; and / or a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a light chain variable region (VL) comprising the amino acid sequence of SEQ ID NO: 21, 41, 52, 61, 71, 78, 82, 87, 91, 103, 112, 117, or 122.

[0421] In some embodiments, B2 comprises: a) a heavy chain CDR1, a heavy chain CDR2, aheavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 25, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 21; b) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 43, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 41; c) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 54, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 52; d) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 63, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 61; e) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 73, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VLcomprising an amino acid sequence of SEQ ID NO: 71; f) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 80, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 78; g) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 84, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 82; h) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 89, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 87; i) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 93, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 91; j) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 93, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 103; k) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 93, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71; l) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 108, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71; m) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 93, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 112; n) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 115, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71; o) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 93, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 117; p) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 124, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VLcomprising an amino acid sequence of SEQ ID NO: 122; q) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 127, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 122; r) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 129, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 122; or s) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 131, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 122.

[0422] In some embodiments, B2 comprises: a) a heavy chain CDR1 comprising the aminoacid sequence of SEQ ID NO: 26, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 28; b) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 46; c) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 26, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 55; d) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 65; e) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 74, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76; f) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76; g) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 74, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 85; h) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76; i)a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; j) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; k) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 125; or l) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 132.

[0423] In some embodiments, B2 comprises: a) a light chain CDR1 comprising the amino acidsequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 24; b) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 42; c) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 53; d) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 62; e) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; f) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 79; g) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 83; h) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising theamino acid sequence of SEQ ID NO: 88; i) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 92; j) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 104; k) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 113; l) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 118; or m) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 123.

[0424] In some embodiments, B2 comprises: a) a heavy chain CDR1 comprising the aminoacid sequence of SEQ ID NO: 26, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 28; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 24; b) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 46; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 42; c) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 26, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 55; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 53; d) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprisingthe amino acid sequence of SEQ ID NO: 65; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 62; e) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 74, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; f) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 79; g) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 74, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 85; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 83; h) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 88; i) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 92; j) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acidsequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 104; k) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; l) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 113; m) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; n) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 118; o) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 125; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 123; or p) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 132; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acidsequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 123.

[0425] In some embodiments, B2 comprises a VH comprising an amino acid sequence of SEQID NO: 25, 43, 54, 63, 73, 80, 84, 89, 93, 108, 115, 124, 127, 129, or 131; and / or a VL comprising an amino acid sequence of SEQ ID NO: 21, 41, 52, 61, 71, 78, 82, 87, 91, 103, 112, 117, or 122.

[0426] In some embodiments, B2 comprises: a) a VH comprising an amino acid sequence ofSEQ ID NO: 25, and a VL comprising an amino acid sequence of SEQ ID NO: 21; b) a VH comprising an amino acid sequence of SEQ ID NO: 43, and a VL comprising an amino acid sequence of SEQ ID NO: 41; c) a VH comprising an amino acid sequence of SEQ ID NO: 54, and a VL comprising an amino acid sequence of SEQ ID NO: 52; d) a VH comprising an amino acid sequence of SEQ ID NO: 63, and a VL comprising an amino acid sequence of SEQ ID NO: 61; e) a VH comprising an amino acid sequence of SEQ ID NO: 73, and a VL comprising an amino acid sequence of SEQ ID NO: 71; f) a VH comprising an amino acid sequence of SEQ ID NO: 80, and a VL comprising an amino acid sequence of SEQ ID NO: 78; g) a VH comprising an amino acid sequence of SEQ ID NO: 84, and a VL comprising an amino acid sequence of SEQ ID NO: 82; h) a VH comprising an amino acid sequence of SEQ ID NO: 89, and a VL comprising an amino acid sequence of SEQ ID NO: 87; i) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VL comprising an amino acid sequence of SEQ ID NO: 91; j) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VL comprising an amino acid sequence of SEQ ID NO: 103; k) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VL comprising an amino acid sequence of SEQ ID NO: 71; l) a VH comprising an amino acid sequence of SEQ ID NO: 108, and a VL comprising an amino acid sequence of SEQ ID NO: 71; m) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VL comprising an amino acid sequence of SEQ ID NO: 112; n) a VH comprising an amino acid sequence of SEQ ID NO: 115, and a VL comprising an amino acid sequence of SEQ ID NO: 71; o) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VL comprising an amino acid sequence of SEQ ID NO: 117; p) a VH comprising an amino acid sequence of SEQ ID NO: 124, and a VL comprising an amino acid sequence of SEQ ID NO: 122; q) a VH comprising an amino acid sequence of SEQ ID NO: 127, and a VL comprising an amino acid sequence of SEQ ID NO: 122; r) a VH comprising an amino acid sequence of SEQ ID NO: 129, and a VLcomprising an amino acid sequence of SEQ ID NO: 122; or s) a VH comprising an amino acid sequence of SEQ ID NO: 131, and a VL comprising an amino acid sequence of SEQ ID NO: 122.

[0427] In some embodiments, (i) B1 specifically binds to a first epitope of a histone H3protein, said first epitope including a lysine (K) residue harboring one or more of a PTM; (ii) B2 specifically binds to both the first binding unit (B1) and to a second epitope of the histone H3 protein, said second epitope not including the PTM; and (iii) the first and the second epitope comprise, or are comprised within, the amino acid sequence selected from (residues harboring PTM in bold text): a) ARTKQTARKSTGGKAP (SEQ ID NO: 230); b) QLATKAARKSAPATGG (SEQ ID NO: 231); and c) LREIRRYQKSTELLIR (SEQ ID NO: 233).

[0428] In some embodiments, (i) B1 specifically binds to a first epitope of a histone H4protein, said first epitope including a lysine (K) residue harboring one or more of a PTM; (ii) B2 specifically binds to both the first binding unit (B1) and to a second epitope of the histone H4 protein, said second epitope not including the PTM; and (iii) the first and the second epitope comprise, or are comprised within, the amino acid sequence KGGAKRHRKVLRDNIQ (SEQ ID NO: 235) (residue harboring PTM in bold text).

[0429] In some embodiments, the lysine (K) residue is trimethylated.

[0430] In some embodiments, the histone H3 protein consists of the amino acid sequence ofany one of SEQ ID NOs: 240-247 and the histone H4 protein consists of the amino acid sequence of SEQ ID NO: 248.

[0431] In some embodiments, the target protein is a platelet-derived growth factor receptorbeta (PDGFRb) protein, a breakpoint cluster region (BCR) protein, a protein tyrosine phosphatase (PTPN11) protein, or a fibroblast growth factor receptor substrate 2 (FRS2) protein.

[0432] In some embodiments, the target protein is a platelet-derived growth factor receptorbeta (PDGFRb) protein, or a fragment thereof, or a breakpoint cluster region (BCR) protein, or a fragment thereof.

[0433] In some embodiments, the first epitope includes a tyrosine (Y) residue that isphosphorylated once.

[0434] In some embodiments, the target protein is a platelet-derived growth factor receptorbeta (PDGFRb) protein, or a fragment thereof, and the tyrosine (Y) residue is positioned at amino acid position 716 of the PDGFRb protein, or a fragment thereof.

[0435] In some embodiments, the target protein is a breakpoint cluster region (BCR) protein,or a fragment thereof, and the tyrosine (Y) residue is positioned at amino acid position 177 of the BCR protein, or a fragment thereof.

[0436] In some embodiments, the target protein is a protein tyrosine phosphatase (PTPN11)protein, or a fragment thereof, and the tyrosine (Y) residue is positioned at amino acid position 580 of the PTPN11 protein, or a fragment thereof.

[0437] In some embodiments, the target protein is a fibroblast growth factor receptor substrate2 (FRS2) protein, or a fragment thereof, and the tyrosine (Y) residue is positioned at amino acid position 196 of the FRS2 protein, or a fragment thereof.

[0438] In some embodiments, B1 comprises a heavy chain complementarity determiningregion 1 (CDR1), a heavy chain CDR2, a heavy chain CDR3 of a heavy chain variable region (VH) comprising the amino acid sequence of SEQ ID NO: 138; and / or a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a light chain variable region (VL) comprising the amino acid sequence of SEQ ID NO: 134 or 148.

[0439] In some embodiments, B1 comprises a heavy chain CDR1 comprising the amino acidsequence of SEQ ID NO: 139, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 140, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 141.

[0440] In some embodiments, B1 comprises a light chain CDR1 comprising the amino acidsequence of SEQ ID NO: 135, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 136, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 137.

[0441] In some embodiments, B1 comprises a heavy chain CDR1 comprising the amino acidsequence of SEQ ID NO: 139, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 140, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 141; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 135, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 136, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 137.

[0442] In some embodiments, B1 comprises a VH comprising an amino acid sequence of SEQID NO: 138, and a VL comprising an amino acid sequence of SEQ ID NO: 134 or 148.

[0443] In some embodiments, B2 comprises a heavy chain complementarity determiningregion 1 (CDR1), a heavy chain CDR2, a heavy chain CDR3 of a heavy chain variable region (VH) comprising the amino acid sequence of SEQ ID NO: 144, 152, 156, 162, 167, 173, or 178; and / or a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a light chain variable region (VL) comprising the amino acid sequence of SEQ ID NO: 71, 151, 160, 165, 172, 176, or 180.

[0444] In some embodiments, B2 comprises: a) a heavy chain CDR1, a heavy chain CDR2, aheavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 144, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71; b) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 152, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 151; c) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 156, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71; d) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 162, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 160; e) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 167, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 165; f) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 173, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 172; g) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 178, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 176; or h) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VH comprising an amino acid sequence of SEQ ID NO: 167, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 180.

[0445] In some embodiments, B2 comprises: a) a heavy chain CDR1 comprising the aminoacid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 145, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 146; b) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 145, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 153; c) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 157, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 146; d) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 157, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 153; or e) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 168, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 169, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 170.

[0446] In some embodiments, B2 comprises: a) a light chain CDR1 comprising the amino acidsequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; b) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 161; c) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 166; d) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 177; or e) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 181.

[0447] In some embodiments, B2 comprises: a) a heavy chain CDR1 comprising the aminoacid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 145, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 146; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a lightchain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; b) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 145, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 153; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; c) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 157, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 146; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; d) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 157, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 153; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 161; e) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 168, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 169, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 170; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 166; f) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 168, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 169, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 170; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 177; or g) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 168, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 169, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 170; or and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 181.

[0448] In some embodiments, B2 comprises a VH comprising an amino acid sequence of SEQID NO: 144, 152, 156, 162, 167, 173, or 178; and / or a VL comprising an amino acid sequence of SEQ ID NO: 71, 151, 160, 165, 172, 176, or 180.

[0449] In some embodiments, B2 comprises: a) a VH comprising an amino acid sequence ofSEQ ID NO: 144, and a VL comprising an amino acid sequence of SEQ ID NO: 71; b) a VH comprising an amino acid sequence of SEQ ID NO: 152, and a VL comprising an amino acid sequence of SEQ ID NO: 151; c) a VH comprising an amino acid sequence of SEQ ID NO: 156, and a VL comprising an amino acid sequence of SEQ ID NO: 71; d) a VH comprising an amino acid sequence of SEQ ID NO: 162, and a VL comprising an amino acid sequence of SEQ ID NO: 160; e) a VH comprising an amino acid sequence of SEQ ID NO: 167, and a VL comprising an amino acid sequence of SEQ ID NO: 165; f) a VH comprising an amino acid sequence of SEQ ID NO: 173, and a VL comprising an amino acid sequence of SEQ ID NO: 172; g) a VH comprising an amino acid sequence of SEQ ID NO: 178, and a VL comprising an amino acid sequence of SEQ ID NO: 176; or h) a VH comprising an amino acid sequence of SEQ ID NO: 167, and a VL comprising an amino acid sequence of SEQ ID NO: 180.

[0450] In some embodiments, (i) B1 specifically binds to a first epitope of a platelet-derivedgrowth factor receptor beta (PDGFRb) protein, said first epitope including a tyrosine (Y) residue harboring one or more of a PTM; (ii) B2 specifically binds to both the first binding unit (B1) and to a second epitope of the PDGFRb protein, said second epitope not including the PTM; and (iii) the first and the second epitope comprise, or are comprised within, the amino acid sequence PSAELYSNALPVG (SEQ ID NO: 236) (residue harboring PTM in bold text).

[0451] In some embodiments, (i) B1 specifically binds to a first epitope of a breakpoint clusterregion (BCR) protein, said first epitope including a tyrosine (Y) residue harboring one or more of a PTM; (ii) B2 specifically binds to both the first binding unit (B1) and a second epitope of the BCR protein, said second epitope not including the PTM; and (iii) the first and the second epitope comprise, or are comprised within, the amino acid sequence AEKPFYVNVEFHH (SEQ ID NO: 237) (residue harboring PTM in bold text).

[0452] In some embodiments, (i) B1 specifically binds to a first epitope of a protein tyrosinephosphatase (PTPN11) protein, said first epitope including a tyrosine (Y) residue harboring oneor more of a PTM; (ii) B2 specifically binds to both the first binding unit (B1) and a second epitope of the PTPN11 protein, said second epitope not including the PTM; and (iii) the first and the second epitope comprise, or are comprised within, the amino acid sequence DSARVYENVGLMQ (SEQ ID NO: 238) (residue harboring PTM in bold text).

[0453] In some embodiments, (i) B1 specifically binds to a first epitope of a fibroblast growthfactor receptor substrate 2 (FRS2) protein, said first epitope including a tyrosine (Y) residue harboring one or more of a PTM; (ii) B2 specifically binds to both the first binding unit (B1) and a second epitope of the FRS2 protein, said second epitope not including the PTM; and (iii) the first and the second epitope comprise, or are comprised within, the amino acid sequence EQVHTYVNTTGVQ (SEQ ID NO: 239) (residue harboring PTM in bold text).

[0454] In some embodiments, the tyrosine (Y) residue is phosphorylated once.

[0455] In some embodiments, the platelet-derived growth factor receptor beta (PDGFRb)protein consists of the amino acid sequence of SEQ ID NO: 249, the breakpoint cluster region (BCR) protein consists of the amino acid sequence of SEQ ID NO: 250, the protein tyrosine phosphatase (PTPN11) protein consists of the amino acid sequence of SEQ ID NO: 251, and the fibroblast growth factor receptor substrate 2 (FRS2) protein consists of the amino acid sequence of SEQ ID NO: 252.

[0456] In some embodiments, one or both of B1 and B2 comprise an antibody or an antigen-binding fragment thereof.

[0457] In some embodiments, the antibody or antigen-binding fragment(s) thereof isrecombinant.

[0458] In some embodiments, the antibody or combination of antibodies or antigen-bindingfragment(s) thereof binds to the target protein at a dissociation constant (KD) of about 1x10-7M or less.

[0459] In some embodiments, the antibody or combination of antibodies or antigen-bindingfragment(s) thereof binds to the target protein at a dissociation constant (KD) from about 3.0x10-10to about 1.2x10-8M.

[0460] In some embodiments, the KD is measured using a peptide immunoprecipitation (IP)assay.

[0461] In some embodiments, one or both of B1 and B2 comprise a humanized antibody orantigen binding fragment thereof, human antibody or antigen binding fragment thereof, murineantibody or antigen binding fragment thereof, chimeric antibody or antigen binding fragment thereof, fragment antigen-binding region (Fab), monovalent Fab', divalent Fab2, F(ab)'3 fragments, single-chain fragment variable (scFv), bis-scFv, (scFv)2, long-neck scFv-Fc, diabody, minibody, nanobody, triabody, tetrabody, disulfide stabilized Fv protein (dsFv), single-domain antibody (sdAb), Ig NAR, single heavy chain antibody, bispecific antibody or biding fragment thereof, bi-specific T-cell engager (BiTE), trispecific antibody, or a derivative thereof.

[0462] In some embodiments, one or both of B1 and B2 comprise a fragment antigen-bindingregion (Fab).

[0463] In some embodiments, one or both of B1 and B2 comprise a single-chain fragmentvariable (scFv).

[0464] In some embodiments, the scFv variable regions are connected by a linker sequence.

[0465] In some embodiments, the linker sequence comprises the amino acid sequenceGILGSGGGGSGGGGSGGGGS (SEQ ID NO: 15) or GILSGSSSSGSSSSGSSSSG (SEQ ID NO: 32).

[0466] In some embodiments, B1 is connected to B2 via a linker sequence.

[0467] In some embodiments, the linker sequence is 10 to 40 amino acids in length.

[0468] In some embodiments, the linker sequence is 15 to 30 amino acids in length.

[0469] In some embodiments, the linker sequence comprises the amino acid sequence(SSSSG)3-SS (SEQ ID NO: 31), (SSSSG)4-SS (SEQ ID NO: 34), or (SSSSG)5-SS (SEQ ID NO: 35).

[0470] In some embodiments, one or both of B1 and B2 comprise an IgG antibody.

[0471] In some embodiments, the IgG antibody is of IgG1, IgG2, IgG3, or IgG4 subclass.

[0472] In some embodiments, the IgG antibody is of IgG1 subclass.

[0473] In some embodiments, the IgG1 antibody compr...

Claims

1. Claims1. An antibody or combination of antibodies or antigen-binding fragment(s) thereof,comprising: (i) a first binding unit (B1) that specifically binds to a first epitope of a targetprotein, wherein the first epitope includes an amino acid residue harboring one or more of a post-translational modification (PTM); and / or (ii) a second binding unit (B2) that specifically binds to both the first binding unit(B1) and a second epitope of the target protein, wherein the second epitope does not include the PTM.

2. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim1, comprising: (i) a first binding unit (B1) that specifically binds to a first epitope of a targetprotein, wherein the first epitope includes an amino acid residue harboring one or more of a post-translational modification (PTM); and (ii) a second binding unit (B2) that specifically binds to both the first binding unit(B1) and a second epitope of the target protein, wherein the second epitope does not include the PTM.

3. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim1 or 2, wherein the PTM is selected from methylation, phosphorylation, acetylation, ubiquitination, glycosylation, formylation, propinylation, butyrylation, crotonylation, benzoylation, 2-hydroxyisobutyrylation, hydroxybutyrylation, lactylation, malonylation, succinylation, glutarylation, hydroxylation, sumoylation, ufmylation, biotinylation, serotonylation, dopaminylation, isomerization, myristoylation, sulfation, nitrosylation, ADP-ribosylation, prenylation, palmitoylation, deamidation, and proteolytic cleavage.

4. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim3, wherein the PTM is methylation or phosphorylation.

5. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of anyone of claims 1-4, wherein the PTM is comprised within a flexible, disordered region of the target protein that does not form a fixed three-dimensional (3D) structure.

6. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of anyone of claims 1-5, wherein the target protein is a histone protein, a platelet-derived growth factor receptor beta (PDGFRb) protein, a breakpoint cluster region (BCR) protein, a protein tyrosine phosphatase (PTPN11) protein, or a fibroblast growth factor receptor substrate 2 (FRS2) protein.

7. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim6, wherein the target protein is a histone protein, or a fragment thereof.

8. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim7, wherein the histone protein is a histone H3 protein, or fragment thereof, or a histone H4 protein, or fragment thereof.

9. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim8, wherein the histone protein is a histone H3 protein, or fragment thereof.

10. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim8, wherein the histone protein is a histone H4 protein, or fragment thereof.

11. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim8, wherein the first epitope includes a lysine (K) residue that is methylated one or more times.

12. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim11, wherein the lysine (K) residue is trimethylated.

13. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim12, wherein the lysine (K) residue is positioned at amino acid position 9, 27, or 56 of the histone H3 protein, or a fragment thereof.

14. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim12, wherein the lysine (K) residue is positioned at amino acid position 20 of the histone H4 protein, or a fragment thereof.

15. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of anyone of claims 1-14, wherein B1 comprises: a) a heavy chain complementarity determining region 1 (CDR1), a heavy chainCDR2, a heavy chain CDR3 of a heavy chain variable region (VH) comprising the amino acid sequence of SEQ ID NO: 6; and / or a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a light chain variable region (VL) comprising the amino acid sequence of SEQ ID NO: 1; or b) a heavy chain complementarity determining region 1 (CDR1), a heavy chainCDR2, a heavy chain CDR3 of a heavy chain variable region (VH) comprising the amino acid sequence of SEQ ID NO: 6; and / or a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a light chain variable region (VL) comprising the amino acid sequence of SEQ ID NO: 2.

16. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim15, wherein B1 comprises a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 7, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 8, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 9.

17. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim15 or 16, wherein B1 comprises a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 3, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 4, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 5.

18. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of anyone of claims 15-17, wherein B1 comprises a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 7, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 8, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 9; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 3, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 4, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 5.

19. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of anyone of claims 15-18, wherein B1 comprises a VH comprising an amino acid sequence of SEQ ID NO: 6, and a VL comprising an amino acid sequence of SEQ ID NO: 1 or 2.

20. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of anyone of claims 15-19, wherein B2 comprises a heavy chain complementarity determining region 1 (CDR1), a heavy chain CDR2, a heavy chain CDR3 of a heavy chain variable region (VH) comprising the amino acid sequence of SEQ ID NO: 25, 43, 54, 63, 73, 80, 84, 89, 93, 108, 115, 124, 127, 129, or 131; and / or a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a light chain variable region (VL) comprising the amino acid sequence of SEQ ID NO: 21, 41, 52, 61, 71, 78, 82, 87, 91, 103, 112, 117, or 122.

21. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim20, wherein B2 comprises: a) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 25, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 21; b) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 43, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 41;c) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 54, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 52;d) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 63, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 61;e) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 73, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71;f) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 80, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 78;g) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 84, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 82;h) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 89, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 87;i) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 93, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 91;j) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 93, and a light chain CDR1, alight chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 103;k) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 93, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71;l) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 108, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71;m) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 93, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 112;n) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 115, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71;o) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 93, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 117;p) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 124, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 122;q) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 127, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 122;r) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 129, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 122; or s) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 131, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 122.

22. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim20 or 21, wherein B2 comprises: a) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 26, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 28; b) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 46; c) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 26, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 55; d) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 65; e) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 74, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76; f) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76;g) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 74, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 85; h) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76; i) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; j) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; k) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 125; or l) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 132.

23. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of anyone of claims 20-22, wherein B2 comprises: a) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 24; b) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 42; c) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 53;d) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 62;e) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72;f) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 79;g) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 83;h) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 88;i) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 92;j) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 104;k) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 113;l) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 118; orm) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 123.

24. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of anyone of claims 20-23, wherein B2 comprises: a) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 26, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 28; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 24; b) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 46; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 42; c) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 26, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 55; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 53; d) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 65; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 62; e) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 74, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a lightchain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72;f) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 79;g) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 74, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 85; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 83;h) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 88;i) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 92;j) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a lightchain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 104;k) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72;l) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 113;m) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72;n) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 118;o) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 125; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 123; or p) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 132; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 123.

25. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of anyone of claims 20-24, wherein B2 comprises a VH comprising an amino acid sequence of SEQ ID NO: 25, 43, 54, 63, 73, 80, 84, 89, 93, 108, 115, 124, 127, 129, or 131; and / or a VL comprising an amino acid sequence of SEQ ID NO: 21, 41, 52, 61, 71, 78, 82, 87, 91, 103, 112, 117, or 122.

26. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim25, wherein B2 comprises: a) a VH comprising an amino acid sequence of SEQ ID NO: 25, and a VLcomprising an amino acid sequence of SEQ ID NO: 21; b) a VH comprising an amino acid sequence of SEQ ID NO: 43, and a VLcomprising an amino acid sequence of SEQ ID NO: 41; c) a VH comprising an amino acid sequence of SEQ ID NO: 54, and a VLcomprising an amino acid sequence of SEQ ID NO: 52; d) a VH comprising an amino acid sequence of SEQ ID NO: 63, and a VLcomprising an amino acid sequence of SEQ ID NO: 61; e) a VH comprising an amino acid sequence of SEQ ID NO: 73, and a VLcomprising an amino acid sequence of SEQ ID NO: 71; f) a VH comprising an amino acid sequence of SEQ ID NO: 80, and a VLcomprising an amino acid sequence of SEQ ID NO: 78; g) a VH comprising an amino acid sequence of SEQ ID NO: 84, and a VLcomprising an amino acid sequence of SEQ ID NO: 82;h) a VH comprising an amino acid sequence of SEQ ID NO: 89, and a VLcomprising an amino acid sequence of SEQ ID NO: 87; i) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VLcomprising an amino acid sequence of SEQ ID NO: 91; j) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VLcomprising an amino acid sequence of SEQ ID NO: 103; k) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VLcomprising an amino acid sequence of SEQ ID NO: 71; l) a VH comprising an amino acid sequence of SEQ ID NO: 108, and a VLcomprising an amino acid sequence of SEQ ID NO: 71; m) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VLcomprising an amino acid sequence of SEQ ID NO: 112; n) a VH comprising an amino acid sequence of SEQ ID NO: 115, and a VLcomprising an amino acid sequence of SEQ ID NO: 71; o) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VLcomprising an amino acid sequence of SEQ ID NO: 117; p) a VH comprising an amino acid sequence of SEQ ID NO: 124, and a VLcomprising an amino acid sequence of SEQ ID NO: 122; q) a VH comprising an amino acid sequence of SEQ ID NO: 127, and a VLcomprising an amino acid sequence of SEQ ID NO: 122; r) a VH comprising an amino acid sequence of SEQ ID NO: 129, and a VLcomprising an amino acid sequence of SEQ ID NO: 122; or s) a VH comprising an amino acid sequence of SEQ ID NO: 131, and a VLcomprising an amino acid sequence of SEQ ID NO: 122.

27. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim6, wherein (i) B1 specifically binds to a first epitope of a histone H3 protein, said first epitope including a lysine (K) residue harboring one or more of a PTM; (ii) B2 specifically binds to both the first binding unit (B1) and to a second epitope of the histone H3 protein, said second epitope not including the PTM; and (iii) the first and the secondepitope comprise, or are comprised within, the amino acid sequence selected from (residues harboring PTM in bold text, below): a) ARTKQTARKSTGGKAP (SEQ ID NO: 230);b) QLATKAARKSAPATGG (SEQ ID NO: 231); andc) LREIRRYQKSTELLIR (SEQ ID NO: 233).

28. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim6, wherein (i) B1 specifically binds to a first epitope of a histone H4 protein, said first epitope including a lysine (K) residue harboring one or more of a PTM; (ii) B2 specifically binds to both the first binding unit (B1) and to a second epitope of the histone H4 protein, said second epitope not including the PTM; and (iii) the first and the second epitope comprise, or are comprised within, the amino acid sequence KGGAKRHRKVLRDNIQ (SEQ ID NO: 235) (residue harboring PTM in bold text).

29. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim27 or 28, wherein the lysine (K) residue is trimethylated.

30. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of anyone of claims 8-29, wherein the histone H3 protein consists of the amino acid sequence of any one of SEQ ID NOs: 240-247 and the histone H4 protein consists of the amino acid sequence of SEQ ID NO: 248.

31. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim6, wherein the target protein is a platelet-derived growth factor receptor beta (PDGFRb) protein, a breakpoint cluster region (BCR) protein, a protein tyrosine phosphatase (PTPN11) protein, or a fibroblast growth factor receptor substrate 2 (FRS2) protein.

32. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim31, wherein the target protein is a platelet-derived growth factor receptor beta (PDGFRb) protein, or a fragment thereof, or a breakpoint cluster region (BCR) protein, or a fragment thereof.

33. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim31, wherein the first epitope includes a tyrosine (Y) residue that is phosphorylated once.

34. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim33, wherein the target protein is a platelet-derived growth factor receptor beta (PDGFRb) protein, or a fragment thereof, and the tyrosine (Y) residue is positioned at amino acid position 716 of the PDGFRb protein, or a fragment thereof.

35. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim33, wherein the target protein is a breakpoint cluster region (BCR) protein, or a fragment thereof, and the tyrosine (Y) residue is positioned at amino acid position 177 of the BCR protein, or a fragment thereof.

36. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim33, wherein the target protein is a protein tyrosine phosphatase (PTPN11) protein, or a fragment thereof, and the tyrosine (Y) residue is positioned at amino acid position 580 of the PTPN11 protein, or a fragment thereof.

37. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim33, wherein the target protein is a fibroblast growth factor receptor substrate 2 (FRS2) protein, or a fragment thereof, and the tyrosine (Y) residue is positioned at amino acid position 196 of the FRS2 protein, or a fragment thereof.

38. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of anyone of claims 1-6 and 31-37, wherein B1 comprises a heavy chain complementarity determining region 1 (CDR1), a heavy chain CDR2, a heavy chain CDR3 of a heavy chain variable region (VH) comprising the amino acid sequence of SEQ ID NO: 138; and / or a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a light chain variable region (VL) comprising the amino acid sequence of SEQ ID NO: 134 or 148.

39. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim38, wherein B1 comprises a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 139, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 140, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 141.

40. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim38 or 39, wherein B1 comprises a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 135, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 136, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 137.

41. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of anyone of claims 38-40, wherein B1 comprises a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 139, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 140, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 141; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 135, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 136, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 137.

42. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of anyone of claims 38-41, wherein B1 comprises a VH comprising an amino acid sequence of SEQ ID NO: 138, and a VL comprising an amino acid sequence of SEQ ID NO: 134 or 148.

43. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of anyone of claims 38-42, wherein B2 comprises a heavy chain complementarity determining region 1 (CDR1), a heavy chain CDR2, a heavy chain CDR3 of a heavy chain variable region (VH) comprising the amino acid sequence of SEQ ID NO: 144, 152, 156, 162, 167, 173, or 178; and / or a light chain CDR1, a light chain CDR2, and a light chain CDR3 of alight chain variable region (VL) comprising the amino acid sequence of SEQ ID NO: 71, 151, 160, 165, 172, 176, or 180.

44. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim43, wherein B2 comprises: a) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 144, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71; b) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 152, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 151; c) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 156, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71; d) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 162, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 160; e) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 167, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 165; f) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 173, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 172; g) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 178, and a light chain CDR1,a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 176; or h) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 167, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 180.

45. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim43 or 44, wherein B2 comprises: a) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 145, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 146; b) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 145, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 153; c) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 157, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 146; d) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 157, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 153; or e) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 168, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 169, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 170.

46. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of anyone of claims 43-45, wherein B2 comprises: a) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72;b) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 161; c) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 166; d) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 177; or e) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 181.

47. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of anyone of claims 43-46, wherein B2 comprises: a) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 145, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 146; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; b) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 145, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 153; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; c) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 157, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 146; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; d) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 157, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 153; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 161; e) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 168, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 169, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 170; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 166; f) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 168, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 169, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 170; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 177; or g) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 168, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 169, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 170; or and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 181.

48. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of anyone of claims 43-47, wherein B2 comprises a VH comprising an amino acid sequence of SEQ ID NO: 144, 152, 156, 162, 167, 173, or 178; and / or a VL comprising an amino acid sequence of SEQ ID NO: 71, 151, 160, 165, 172, 176, or 180.

49. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim48, wherein B2 comprises: a) a VH comprising an amino acid sequence of SEQ ID NO: 144, and a VLcomprising an amino acid sequence of SEQ ID NO: 71; b) a VH comprising an amino acid sequence of SEQ ID NO: 152, and a VLcomprising an amino acid sequence of SEQ ID NO: 151; c) a VH comprising an amino acid sequence of SEQ ID NO: 156, and a VLcomprising an amino acid sequence of SEQ ID NO: 71; d) a VH comprising an amino acid sequence of SEQ ID NO: 162, and a VLcomprising an amino acid sequence of SEQ ID NO: 160; e) a VH comprising an amino acid sequence of SEQ ID NO: 167, and a VLcomprising an amino acid sequence of SEQ ID NO: 165; f) a VH comprising an amino acid sequence of SEQ ID NO: 173, and a VLcomprising an amino acid sequence of SEQ ID NO: 172; g) a VH comprising an amino acid sequence of SEQ ID NO: 178, and a VLcomprising an amino acid sequence of SEQ ID NO: 176; or h) a VH comprising an amino acid sequence of SEQ ID NO: 167, and a VLcomprising an amino acid sequence of SEQ ID NO: 180.

50. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim6, wherein (i) B1 specifically binds to a first epitope of a platelet-derived growth factor receptor beta (PDGFRb) protein, said first epitope including a tyrosine (Y) residue harboring one or more of a PTM; (ii) B2 specifically binds to both the first binding unit (B1) and to a second epitope of the PDGFRb protein, said second epitope not including the PTM; and (iii) the first and the second epitope comprise, or are comprised within, the amino acid sequence PSAELYSNALPVG (SEQ ID NO: 236) (residue harboring PTM in bold text).

51. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim6, wherein (i) B1 specifically binds to a first epitope of a breakpoint cluster region (BCR)protein, said first epitope including a tyrosine (Y) residue harboring one or more of a PTM; (ii) B2 specifically binds to both the first binding unit (B1) and a second epitope of the BCR protein, said second epitope not including the PTM; and (iii) the first and the second epitope comprise, or are comprised within, the amino acid sequence AEKPFYVNVEFHH (SEQ ID NO: 237) (residue harboring PTM in bold text).

52. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim6, wherein (i) B1 specifically binds to a first epitope of a protein tyrosine phosphatase (PTPN11) protein, said first epitope including a tyrosine (Y) residue harboring one or more of a PTM; (ii) B2 specifically binds to both the first binding unit (B1) and a second epitope of the PTPN11 protein, said second epitope not including the PTM; and (iii) the first and the second epitope comprise, or are comprised within, the amino acid sequence DSARVYENVGLMQ (SEQ ID NO: 238) (residue harboring PTM in bold text).

53. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim6, wherein (i) B1 specifically binds to a first epitope of a fibroblast growth factor receptor substrate 2 (FRS2) protein, said first epitope including a tyrosine (Y) residue harboring one or more of a PTM; (ii) B2 specifically binds to both the first binding unit (B1) and a second epitope of the FRS2 protein, said second epitope not including the PTM; and (iii) the first and the second epitope comprise, or are comprised within, the amino acid sequence EQVHTYVNTTGVQ (SEQ ID NO: 239) (residue harboring PTM in bold text).

54. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of anyone of claims 50-53, wherein the tyrosine (Y) residue is phosphorylated once.

55. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of anyone of claims 31-54, wherein the platelet-derived growth factor receptor beta (PDGFRb) protein consists of the amino acid sequence of SEQ ID NO: 249, the breakpoint cluster region (BCR) protein consists of the amino acid sequence of SEQ ID NO: 250, the protein tyrosine phosphatase (PTPN11) protein consists of the amino acid sequence of SEQ IDNO: 251, and the fibroblast growth factor receptor substrate 2 (FRS2) protein consists of the amino acid sequence of SEQ ID NO: 252.

56. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of anyone of claims 1-55, wherein one or both of B1 and B2 comprise an antibody or an antigen- binding fragment thereof.

57. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim56, wherein the antibody or antigen-binding fragment(s) thereof is recombinant.

58. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of anyone of claims 1-57, wherein the antibody or combination of antibodies or antigen-binding fragment(s) thereof binds to the target protein at a dissociation constant (KD) of about 1x10-7M or less.

59. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of anyone of claims 1-58, wherein the antibody or combination of antibodies or antigen-binding fragment(s) thereof binds to the target protein at a dissociation constant (KD) from about 3.0x10-10to about 1.2x10-8M.

60. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim58 or 59, wherein the KD is measured using a peptide immunoprecipitation (IP) assay.

61. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim56 or 57, wherein one or both of B1 and B2 comprise a humanized antibody or antigen- binding fragment thereof, human antibody or antigen-binding fragment thereof, murine antibody or antigen-binding fragment thereof, chimeric antibody or antigen-binding fragment thereof, fragment antigen-binding region (Fab), monovalent Fab', divalent Fab2, F(ab)'3 fragments, single-chain fragment variable (scFv), bis-scFv, (scFv)2, long-neck scFv-Fc, diabody, minibody, nanobody, triabody, tetrabody, disulfide stabilized Fv protein (dsFv), single-domain antibody (sdAb), Ig NAR, single heavy chain antibody, bispecificantibody or biding fragment thereof, bi-specific T-cell engager (BiTE), trispecific antibody, or a derivative thereof.

62. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim61, wherein one or both of B1 and B2 comprise a fragment antigen-binding region (Fab).

63. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim61, wherein one or both of B1 and B2 comprise a single-chain fragment variable (scFv).

64. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim63, wherein the scFv variable regions are connected by a linker sequence.

65. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim64, wherein the linker sequence comprises the amino acid sequence GILGSGGGGSGGGGSGGGGS (SEQ ID NO: 15) or GILSGSSSSGSSSSGSSSSG (SEQ ID NO: 32).

66. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of anyone of claims 63-65, wherein B1 is connected to B2 via a linker sequence.

67. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim66, wherein the linker sequence is 10 to 40 amino acids in length.

68. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim67, wherein the linker sequence is 15 to 30 amino acids in length.

69. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim68, wherein the linker sequence comprises the amino acid sequence (SSSSG)3-SS (SEQ ID NO: 31), (SSSSG)4-SS (SEQ ID NO: 34), or (SSSSG)5-SS (SEQ ID NO: 35).

70. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of anyone of claims 1-69, wherein one or both of B1 and B2 comprise an IgG antibody.

71. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim70, wherein the IgG antibody is of IgG1, IgG2, IgG3, or IgG4 subclass.

72. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim71, wherein the IgG antibody is of IgG1 subclass.

73. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim72, wherein the IgG1 antibody comprises one or more of an Fc domain.

74. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim73, wherein the IgG1 antibody or antigen-binding fragment comprises a S239C mutation in the Fc domain(s).

75. The antibody or combination of antibodies or antigen-binding fragment(s) thereof ofclaim 73, wherein the IgG1 antibody or antigen-binding fragment comprises T252M and / or T254S mutations in the Fc domain(s).

76. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of anyone of claims 73-75, comprising two Fc domains that dimerize to form an Fc heterodimer.

77. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim76, wherein the Fc domains in the Fc heterodimer comprise knob-in-hole mutations as compared to a wild-type Fc domain.

78. The antibody or combination of antibodies or antigen-binding fragment(s) thereof ofclaim 77, wherein one Fc domain in the Fc heterodimer comprises amino acid substitutions P354C and T366W (according to EU numbering) as compared to a wild-type Fc domain, and the other Fc domain in the Fc heterodimer comprises amino acidsubstitutions Y349C, T366S, M368A, and Y407V (according to EU numbering) as compared to a wild-type Fc domain.

79. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of anyone of claims 73-78, wherein one or both of B1 and B2 are connected to the Fc domain via a linker sequence.

80. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim79, wherein the linker sequence is 10 to 40 amino acids in length.

81. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim80, wherein the linker sequence is 15 to 30 amino acids in length.

82. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim81, wherein the linker sequence comprises the amino acid sequence SSLERSSSSSGSSSSGSSGRS (SEQ ID NO: 16), RTVLSSLERSSSSSGSSSSGSSGRS (SEQ ID NO: 142), or RTVSLERSSSSSGSSSSGSSGRS (SEQ ID NO: 100).

83. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of anyone of claims 79-82, wherein a hinge sequence separates the linker sequence and the Fc domain(s).

84. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim83, wherein the hinge sequence comprises the amino acid sequence GCKPCICT (SEQ ID NO: 17).

85. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of anyone of claims 76-84, wherein one of the Fc domains that form the Fc heterodimer comprises the amino acid sequence of SEQ ID NO: 187, and the other of the Fc domains that form the Fc heterodimer comprises the amino acid sequence of SEQ ID NO: 188.

86. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of anyone of claims 1-85, wherein one or both of B1 and B2 are attached to a solid support or a cell surface.

87. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim86, wherein the solid support is a bead, a membrane, a plate, a tube, a column, a biosensor chip, or Sepharose.

88. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim86 or 87, wherein one or both of B1 and B2 are attached to the solid support using an affinity binding pair.

89. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim88, wherein one member of the affinity binding pair comprises a biotin moiety, and the other member of the affinity binding pair comprises a streptavidin moiety.

90. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim86, wherein one or both of B1 and B2 are attached to the cell surface using an anchoring protein.

91. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim90, wherein the anchoring protein is Aga2 anchoring protein.

92. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim91, wherein the Aga2 anchoring protein comprises the amino acid sequence MQLLRCFSIFSVIASVLAQELTTICEQIPSPTLESTPYSLSTTTILANGKAMQGVFEY YKSVTFVSNCGSHPSTTSKGSPINTQYVF (SEQ ID NO: 29).

93. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of anyone of claims 86 and 90-91, wherein the cell is a yeast cell.

94. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim88 or 90, wherein the first or second member of the affinity binding pair, or the anchoring protein, is connected to one or both of B1 and B2 via a linker sequence.

95. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of anyone of claims 1-94, further comprising one or more of a reporter protein or a protein tag.

96. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim95, wherein the protein tag is an affinity tag.

97. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim95, wherein the reporter protein or the protein tag is a V5 epitope tag (V5-tag), an biotinylation tag, a polyhistidine tag (His-tag), a fluorescent protein, a c-myc tag, a glutathione S-transferase (GST) tag, a FLAG tag, an HA tag, an S-tag, a FLASH tag, a SNAP-tag, a streptavidin moiety, a Strep II tag, an HA tag, an L14 tag, a 4C-RGD tag, an LH tag, a protein A, a maltose-binding protein (MBP), an albumin-binding protein, a chitin binding domain, a calmodulin binding peptide, a cellulose binding domain, a biotin moiety, an oligonucleotide (oligo), or a horseradish peroxidase (HRP).

98. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim97, wherein the reporter protein or the protein tag is a V5 epitope tag (V5-tag), a biotinylation tag, or a polyhistidine tag (His-tag).

99. The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim98, wherein the V5-tag comprises the amino acid sequence GKPIPNPLLGLDST (SEQ ID NO: 33). 100.The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim 98, wherein the His-tag comprises the amino acid sequence HHHHHH (SEQ ID NO: 99).101.The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim 98, wherein the biotinylation tag is Avitag. 102.The antibody or combination of antibodies or antigen-binding fragment(s) thereof of claim 101, wherein the Avitag comprises the amino acid sequence GLNDIFEAQKIEWHE (SEQ ID NO: 14). 103.An antibody fusion molecule, comprising: a) a first binding unit (B1), comprising:(i) a first heavy chain region of a first Fab (“Fab1”);(ii) a first light chain that pairs with the first heavy chain region to form Fab1,wherein Fab1 comprises a first antigen-binding domain (“ABD1”) that specifically binds to a first epitope of a target protein, wherein the first epitope includes an amino acid residue harboring one or more of a post-translational modification (PTM); and b) a second binding unit (B2), comprising:(i) a second heavy chain region of a second Fab (“Fab2”)(ii) a second light chain that pairs with the second heavy chain region to formFab2, wherein Fab2 comprises a second antigen-binding domain (“ABD2”) that specifically binds to both the first binding unit (B1) and a second epitope of the target protein, wherein the second epitope does not include the PTM; and wherein each of Fab1 and Fab2 are connected to a biotinylation tag comprising a biotin moiety via a linker sequence, wherein the biotin moiety forms a first member of an affinity binding pair. 104.The antibody fusion molecule of claim 103, wherein the first member of the affinity binding pair is non-covalently attached to a second member of the affinity binding pair, said second member comprising a streptavidin moiety.105.The antibody fusion molecule of claim 103 or 104, wherein the second member of the affinity binding pair is immobilized on a solid support. 106.The antibody fusion molecule of claim 105, wherein the solid support is a bead, a membrane, a plate, a tube, a column, a biosensor chip, or Sepharose. 107.The antibody fusion molecule of any one of claims 103-106, wherein the PTM is selected from methylation, phosphorylation, acetylation, ubiquitination, glycosylation, formylation, propinylation, butyrylation, crotonylation, benzoylation, 2-hydroxyisobutyrylation, hydroxybutyrylation, lactylation, malonylation, succinylation, glutarylation, hydroxylation, sumoylation, ufmylation, biotinylation, serotonylation, dopaminylation, isomerization, myristoylation, sulfation, nitrosylation, ADP-ribosylation, prenylation, palmitoylation, deamidation, and proteolytic cleavage. 108.The antibody fusion molecule of claim 107, wherein the PTM is methylation or phosphorylation. 109.The antibody fusion molecule of any one of claims 103-108, wherein the PTM is comprised within a flexible, disordered region of the target protein that does not form a fixed three-dimensional (3D) structure. 110.The antibody fusion molecule of any one of claims 103-109, wherein the target protein is a histone protein, a platelet-derived growth factor receptor beta (PDGFRb) protein, a breakpoint cluster region (BCR) protein, a protein tyrosine phosphatase (PTPN11) protein, or a fibroblast growth factor receptor substrate 2 (FRS2) protein. 111.The antibody fusion molecule of claim 110, wherein the target protein is a histone protein, or a fragment thereof. 112.The antibody fusion molecule of claim 111, wherein the histone protein is a histone H3 protein, or fragment thereof, or a histone H4 protein, or fragment thereof.113.The antibody fusion molecule of claim 112, wherein the histone protein is a histone H3 protein, or fragment thereof. 114.The antibody fusion molecule of claim 112, wherein the histone protein is a histone H4 protein, or fragment thereof. 115.The antibody fusion molecule of claim 112, wherein the first epitope includes a lysine (K) residue that is methylated one or more times. 116.The antibody fusion molecule of claim 115, wherein the lysine (K) residue is trimethylated. 117.The antibody fusion molecule of claim 116, wherein the lysine (K) residue is positioned at amino acid position 9, 27, or 56 of the histone H3 protein, or a fragment thereof. 118.The antibody fusion molecule of claim 116, wherein the lysine (K) residue is positioned at amino acid position 20 of the histone H4 protein, or a fragment thereof. 119.The antibody fusion molecule of any one of claims 103-118, wherein B1 comprises: a) a heavy chain complementarity determining region 1 (CDR1), a heavy chainCDR2, a heavy chain CDR3 of a heavy chain variable region (VH) comprising the amino acid sequence of SEQ ID NO: 6; and / or a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a light chain variable region (VL) comprising the amino acid sequence of SEQ ID NO: 1; or b) a heavy chain complementarity determining region 1 (CDR1), a heavy chainCDR2, a heavy chain CDR3 of a heavy chain variable region (VH) comprising the amino acid sequence of SEQ ID NO: 6; and / or a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a light chain variable region (VL) comprising the amino acid sequence of SEQ ID NO: 2.120.The antibody fusion molecule of claim 119, wherein B1 comprises a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 7, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 8, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO:

9. 121.The antibody fusion molecule of claim 119 or 120, wherein B1 comprises a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 3, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 4, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO:

5. 122.The antibody fusion molecule of any one of claims 119-121, wherein B1 comprises a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 7, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 8, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 9; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 3, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 4, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO:

5. 123.The antibody fusion molecule of any one of claims 119-122, wherein B1 comprises a VH comprising an amino acid sequence of SEQ ID NO: 6, and a VL comprising an amino acid sequence of SEQ ID NO: 1 or 2. 124.The antibody fusion molecule of any one of claims 119-123, wherein B2 comprises a heavy chain complementarity determining region 1 (CDR1), a heavy chain CDR2, a heavy chain CDR3 of a heavy chain variable region (VH) comprising the amino acid sequence of SEQ ID NO: 25, 43, 54, 63, 73, 80, 84, 89, 93, 108, 115, 124, 127, 129, or 131; and / or a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a light chain variable region (VL) comprising the amino acid sequence of SEQ ID NO: 21, 41, 52, 61, 71, 78, 82, 87, 91, 103, 112, 117, or 122. 125.The antibody fusion molecule of claim 124, wherein B2 comprises:a) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 25, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 21;b) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 43, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 41;c) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 54, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 52;d) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 63, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 61;e) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 73, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71;f) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 80, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 78;g) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 84, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 82;h) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 89, and a light chain CDR1, alight chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 87;i) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 93, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 91;j) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 93, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 103;k) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 93, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71;l) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 108, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71;m) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 93, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 112;n) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 115, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71;o) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 93, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 117;p) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 124, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 122; q) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 127, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 122; r) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 129, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 122; or s) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 131, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO:

122. 126.The antibody fusion molecule of claim 124 or 125, wherein B2 comprises: a) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 26, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 28; b) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 46; c) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 26, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 55; d) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 65;e) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 74, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76; f) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76; g) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 74, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 85; h) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76; i) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; j) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; k) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 125; or l) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO:

132. 127.The antibody fusion molecule of any one of claims 124-126, wherein B2 comprises: a) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 24;b) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 42;c) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 53;d) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 62;e) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72;f) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 79;g) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 83;h) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 88;i) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 92;j) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 104;k) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 113;l) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 118; or m) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO:

123. 128.The antibody fusion molecule of any one of claims 124-127, wherein B2 comprises: a) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 26, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 28; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 24; b) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 46; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 42; c) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 26, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 55; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 53; d) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 65; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a lightchain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 62;e) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 74, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72;f) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 79;g) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 74, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 85; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 83;h) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 88;i) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a lightchain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 92;j) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 104;k) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72;l) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 113;m) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72;n) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a lightchain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 118; o) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 125; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 123; or p) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 132; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO:

123. 129.The antibody fusion molecule of claim 128, wherein B2 comprises: a) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 26, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 28; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 24; b) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 46; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 42; c) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 26, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 55; and alight chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 53; d) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 65; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 62; e) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 92; f) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; or g) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO:

118. 130.The antibody fusion molecule of any one of claims 124-129, wherein B2 comprises a VH comprising an amino acid sequence of SEQ ID NO: 25, 43, 54, 63, 73, 80, 84, 89, 93, 108,115, 124, 127, 129, or 131; and / or a VL comprising an amino acid sequence of SEQ ID NO: 21, 41, 52, 61, 71, 78, 82, 87, 91, 103, 112, 117, or 122. 131.The antibody fusion molecule of claim 130, wherein B2 comprises a VH comprising an amino acid sequence of SEQ ID NO: 25, 43, 54, 63, 93, or 108; and / or a VL comprising an amino acid sequence of SEQ ID NO: 21, 41, 52, 61, 71, 91, or 117. 132.The antibody fusion molecule of claim 130, wherein B2 comprises: a) a VH comprising an amino acid sequence of SEQ ID NO: 25, and a VLcomprising an amino acid sequence of SEQ ID NO: 21; b) a VH comprising an amino acid sequence of SEQ ID NO: 43, and a VLcomprising an amino acid sequence of SEQ ID NO: 41; c) a VH comprising an amino acid sequence of SEQ ID NO: 54, and a VLcomprising an amino acid sequence of SEQ ID NO: 52; d) a VH comprising an amino acid sequence of SEQ ID NO: 63, and a VLcomprising an amino acid sequence of SEQ ID NO: 61; e) a VH comprising an amino acid sequence of SEQ ID NO: 73, and a VLcomprising an amino acid sequence of SEQ ID NO: 71; f) a VH comprising an amino acid sequence of SEQ ID NO: 80, and a VLcomprising an amino acid sequence of SEQ ID NO: 78; g) a VH comprising an amino acid sequence of SEQ ID NO: 84, and a VLcomprising an amino acid sequence of SEQ ID NO: 82; h) a VH comprising an amino acid sequence of SEQ ID NO: 89, and a VLcomprising an amino acid sequence of SEQ ID NO: 87; i) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VLcomprising an amino acid sequence of SEQ ID NO: 91; j) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VLcomprising an amino acid sequence of SEQ ID NO: 103; k) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VLcomprising an amino acid sequence of SEQ ID NO: 71;l) a VH comprising an amino acid sequence of SEQ ID NO: 108, and a VLcomprising an amino acid sequence of SEQ ID NO: 71; m) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VLcomprising an amino acid sequence of SEQ ID NO: 112; n) a VH comprising an amino acid sequence of SEQ ID NO: 115, and a VLcomprising an amino acid sequence of SEQ ID NO: 71; o) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VLcomprising an amino acid sequence of SEQ ID NO: 117; p) a VH comprising an amino acid sequence of SEQ ID NO: 124, and a VLcomprising an amino acid sequence of SEQ ID NO: 122; q) a VH comprising an amino acid sequence of SEQ ID NO: 127, and a VLcomprising an amino acid sequence of SEQ ID NO: 122; r) a VH comprising an amino acid sequence of SEQ ID NO: 129, and a VLcomprising an amino acid sequence of SEQ ID NO: 122; or s) a VH comprising an amino acid sequence of SEQ ID NO: 131, and a VLcomprising an amino acid sequence of SEQ ID NO:

122. 133.The antibody fusion molecule of claim 132, wherein B2 comprises: a) a VH comprising an amino acid sequence of SEQ ID NO: 25, and a VLcomprising an amino acid sequence of SEQ ID NO: 21; b) a VH comprising an amino acid sequence of SEQ ID NO: 43, and a VLcomprising an amino acid sequence of SEQ ID NO: 41; c) a VH comprising an amino acid sequence of SEQ ID NO: 54, and a VLcomprising an amino acid sequence of SEQ ID NO: 52; d) a VH comprising an amino acid sequence of SEQ ID NO: 63, and a VLcomprising an amino acid sequence of SEQ ID NO: 61; e) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VLcomprising an amino acid sequence of SEQ ID NO: 91; f) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VLcomprising an amino acid sequence of SEQ ID NO: 71;g) a VH comprising an amino acid sequence of SEQ ID NO: 108, and a VLcomprising an amino acid sequence of SEQ ID NO: 71; or h) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VLcomprising an amino acid sequence of SEQ ID NO:

117. 134.The antibody fusion molecule of any one of claims 112-133, wherein the histone H3 protein consists of the amino acid sequence of any one of SEQ ID NOs: 240-247 and the histone H4 protein consists of the amino acid sequence of SEQ ID NO:

248. 135.The antibody fusion molecule of claim 110, wherein the target protein is a platelet- derived growth factor receptor beta (PDGFRb) protein, a breakpoint cluster region (BCR) protein, a protein tyrosine phosphatase (PTPN11) protein, or a fibroblast growth factor receptor substrate 2 (FRS2) protein. 136.The antibody fusion molecule of claim 135, wherein the target protein is a platelet- derived growth factor receptor beta (PDGFRb) protein, or a fragment thereof, or a breakpoint cluster region (BCR) protein, or a fragment thereof. 137.The antibody fusion molecule of claim 135, wherein the first epitope includes a tyrosine (Y) residue that is phosphorylated once. 138.The antibody fusion molecule of claim 137, wherein the target protein is a platelet- derived growth factor receptor beta (PDGFRb) protein, or a fragment thereof, and the tyrosine (Y) residue is positioned at amino acid position 716 of the PDGFRb protein, or a fragment thereof. 139.The antibody fusion molecule of claim 137, wherein the target protein is a breakpoint cluster region (BCR) protein, or a fragment thereof, and the tyrosine (Y) residue is positioned at amino acid position 177 of the BCR protein, or a fragment thereof.140.The antibody fusion molecule of claim 137, wherein the target protein is a protein tyrosine phosphatase (PTPN11) protein, or a fragment thereof, and the tyrosine (Y) residue is positioned at amino acid position 580 of the PTPN11 protein, or a fragment thereof. 141.The antibody fusion molecule of claim 137, wherein the target protein is a fibroblast growth factor receptor substrate 2 (FRS2) protein, or a fragment thereof, and the tyrosine (Y) residue is positioned at amino acid position 196 of the FRS2 protein, or a fragment thereof. 142.The antibody fusion molecule of any one of claims 103-110 and 135-141, wherein B1 comprises a heavy chain complementarity determining region 1 (CDR1), a heavy chain CDR2, a heavy chain CDR3 of a heavy chain variable region (VH) comprising the amino acid sequence of SEQ ID NO: 138; and / or a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a light chain variable region (VL) comprising the amino acid sequence of SEQ ID NO: 134 or 148. 143.The antibody fusion molecule of claim 142, wherein B1 comprises a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 139, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 140, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO:

141. 144.The antibody fusion molecule of claim 142 or 143, wherein B1 comprises a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 135, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 136, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO:

137. 145.The antibody fusion molecule of any one of claims 142-144, wherein B1 comprises a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 139, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 140, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 141; and a light chain CDR1comprising the amino acid sequence of SEQ ID NO: 135, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 136, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO:

137. 146.The antibody fusion molecule of any one of claims 142-145, wherein B1 comprises a VH comprising an amino acid sequence of SEQ ID NO: 138, and a VL comprising an amino acid sequence of SEQ ID NO: 134 or 148. 147.The antibody fusion molecule of any one of claims 103-110 and 135-146, wherein B2 comprises a heavy chain complementarity determining region 1 (CDR1), a heavy chain CDR2, a heavy chain CDR3 of a heavy chain variable region (VH) comprising the amino acid sequence of SEQ ID NO: 144, 152, 156, 162, 167, 173, or 178; and / or a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a light chain variable region (VL) comprising the amino acid sequence of SEQ ID NO: 71, 151, 160, 165, 172, 176, or 180. 148.The antibody fusion molecule of claim 147, wherein B2 comprises: a) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 144, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71; b) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 152, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 151; c) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 156, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71; d) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 162, and a light chain CDR1,a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 160; e) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 167, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 165; f) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 173, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 172; g) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 178, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 176; or h) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 167, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO:

180. 149.The antibody fusion molecule of claim 147 or 148, wherein B2 comprises: a) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 145, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 146; b) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 145, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 153; c) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 157, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 146;d) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 157, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 153; or e) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 168, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 169, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO:

170. 150.The antibody fusion molecule of any one of any one of claims 147-149, wherein B2 comprises: a) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; b) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 161; c) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 166; d) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 177; or e) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO:

181. 151.The antibody fusion molecule of any one of claims 147-150, wherein B2 comprises: a) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 145, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 146; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72;b) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 145, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 153; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72;c) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 157, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 146; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72;d) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 157, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 153; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 161;e) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 168, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 169, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 170; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 166;f) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 168, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 169, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 170; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 177; or g) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 168, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 169, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 170; or and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO:

181. 152.The antibody fusion molecule of any one of claims 147-151, wherein B2 comprises a VH comprising an amino acid sequence of SEQ ID NO: 144, 152, 156, 162, 167, 173, or 178; and / or a VL comprising an amino acid sequence of SEQ ID NO: 71, 151, 160, 165, 172, 176, or 180. 153.The antibody fusion molecule of any one of claims 147-152, wherein B2 comprises: a) a VH comprising an amino acid sequence of SEQ ID NO: 144, and a VLcomprising an amino acid sequence of SEQ ID NO: 71; b) a VH comprising an amino acid sequence of SEQ ID NO: 152, and a VLcomprising an amino acid sequence of SEQ ID NO: 151; c) a VH comprising an amino acid sequence of SEQ ID NO: 156, and a VLcomprising an amino acid sequence of SEQ ID NO: 71; d) a VH comprising an amino acid sequence of SEQ ID NO: 162, and a VLcomprising an amino acid sequence of SEQ ID NO: 160; e) a VH comprising an amino acid sequence of SEQ ID NO: 167, and a VLcomprising an amino acid sequence of SEQ ID NO: 165; f) a VH comprising an amino acid sequence of SEQ ID NO: 173, and a VLcomprising an amino acid sequence of SEQ ID NO: 172; g) a VH comprising an amino acid sequence of SEQ ID NO: 178, and a VLcomprising an amino acid sequence of SEQ ID NO: 176; or h) a VH comprising an amino acid sequence of SEQ ID NO: 167, and a VLcomprising an amino acid sequence of SEQ ID NO: 180.154.The antibody fusion molecule of any one of claims 135-153, wherein the platelet-derived growth factor receptor beta (PDGFRb) protein consists of the amino acid sequence of SEQ ID NO: 249, the breakpoint cluster region (BCR) protein consists of the amino acid sequence of SEQ ID NO: 250, the protein tyrosine phosphatase (PTPN11) protein consists of the amino acid sequence of SEQ ID NO: 251, and the fibroblast growth factor receptor substrate 2 (FRS2) protein consists of the amino acid sequence of SEQ ID NO:

252. 155.The antibody fusion molecule of any one of claims 103-154, wherein Fab1 is formed by a first heavy chain region comprising an amino acid sequence of SEQ ID NO: 257, or an amino acid sequence having at least 75% identity thereto, and a first light chain comprising an amino acid sequence of SEQ ID NO: 18, or an amino acid sequence having at least 75% identity thereto. 156.The antibody fusion molecule of any one of claims 103-155, wherein Fab2 is formed by a) a second heavy chain region comprising an amino acid sequence of SEQ ID NO:258, or an amino acid sequence having at least 75% identity thereto, and a second light chain comprising an amino acid sequence of SEQ ID NO: 36, or an amino acid sequence having at least 75% identity thereto; b) a second heavy chain region comprising an amino acid sequence of SEQ ID NO:259, or an amino acid sequence having at least 75% identity thereto, and a second light chain comprising an amino acid sequence of SEQ ID NO: 47, or an amino acid sequence having at least 75% identity thereto; c) a second heavy chain region comprising an amino acid sequence of SEQ ID NO:260, or an amino acid sequence having at least 75% identity thereto, and a second light chain comprising an amino acid sequence of SEQ ID NO: 56, or an amino acid sequence having at least 75% identity thereto; d) a second heavy chain region comprising an amino acid sequence of SEQ ID NO:261, or an amino acid sequence having at least 75% identity thereto, and a second light chain comprising an amino acid sequence of SEQ ID NO: 66, or an amino acid sequence having at least 75% identity thereto;e) a second heavy chain region comprising an amino acid sequence of SEQ ID NO:262, or an amino acid sequence having at least 75% identity thereto, and a second light chain comprising an amino acid sequence of SEQ ID NO: 97, or an amino acid sequence having at least 75% identity thereto; f) a second heavy chain region comprising an amino acid sequence of SEQ ID NO:262, or an amino acid sequence having at least 75% identity thereto, and a second light chain comprising an amino acid sequence of SEQ ID NO: 107, or an amino acid sequence having at least 75% identity thereto; g) a second heavy chain region comprising an amino acid sequence of SEQ ID NO:263, or an amino acid sequence having at least 75% identity thereto, and a second light chain comprising an amino acid sequence of SEQ ID NO: 107, or an amino acid sequence having at least 75% identity thereto; or h) a second heavy chain region comprising an amino acid sequence of SEQ ID NO:262, or an amino acid sequence having at least 75% identity thereto, and a second light chain comprising an amino acid sequence of SEQ ID NO: 120, or an amino acid sequence having at least 75% identity thereto. 157.The antibody fusion molecule of any one of claims 103-156, wherein the linker is selected from Gn (SEQ ID NO: 253, where n is any integer, e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10); GnS (SEQ ID NO: 254, where n is any integer, e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10), SGn(SEQ ID NO: 255, where n is any integer, e.g., 1, 2, 3, 4, 5, 6, or 7, 8, 9 or 10), and (GGGGS)n (SEQ ID NO: 256, where n is any integer, e.g., 1, 2, 3, 4, 5, 6, or 7, 8, 9 or 10), (SSSSG)3-SS (SEQ ID NO: 31), (SSSSG)4-SS (SEQ ID NO: 34), and (SSSSG)5-SS (SEQ ID NO: 35). 158.The antibody fusion molecule of any one of claims 103-157, wherein the biotinylation tag is Avitag. 159.The antibody fusion molecule of claim 158, wherein the Avitag comprises the amino acid sequence GLNDIFEAQKIEWHE (SEQ ID NO: 14).160.An antibody fusion molecule, comprising: a) a first binding unit (B1) comprising a first scFv, said first scFv comprising a firstantigen-binding domain (“ABD1”) that specifically binds to a first epitope of a target protein, wherein the first epitope includes an amino acid residue harboring one or more of a post-translational modification (PTM); and b) a second binding unit (B2) comprising a second scFv, said second scFv comprisinga second antigen-binding domain (“ABD2”) that specifically binds to both the first binding unit (B1) and a second epitope of the target protein, wherein the second epitope does not include the PTM; wherein: (i) the variable regions of the first scFv are connected by a first linker sequenceand the variable regions of the second scFv are connected by a second linker sequence; (ii) the first scFv is connected to the second scFv via a third linker sequence, saidthird linker sequence being 10 to 40 amino acids in length; and (iii) wherein either the first scFv or the second scFv is further connected to ananchoring protein via a fourth linker sequence, said anchoring protein being capable of attaching to a cell surface. 161.The antibody fusion molecule of claim 160, wherein the PTM is selected from methylation, phosphorylation, acetylation, ubiquitination, glycosylation, formylation, propinylation, butyrylation, crotonylation, benzoylation, 2-hydroxyisobutyrylation, hydroxybutyrylation, lactylation, malonylation, succinylation, glutarylation, hydroxylation, sumoylation, ufmylation, biotinylation, serotonylation, dopaminylation, isomerization, myristoylation, sulfation, nitrosylation, ADP-ribosylation, prenylation, palmitoylation, deamidation, and proteolytic cleavage. 162.The antibody fusion molecule of claim 161, wherein the PTM is methylation or phosphorylation.163.The antibody fusion molecule of any one of claims 160-162, wherein the PTM is comprised within a flexible, disordered region of the target protein that does not form a fixed three-dimensional (3D) structure. 164.The antibody fusion molecule of any one of claims 160-163, wherein the target protein is a histone protein, a platelet-derived growth factor receptor beta (PDGFRb) protein, a breakpoint cluster region (BCR) protein, a protein tyrosine phosphatase (PTPN11) protein, or a fibroblast growth factor receptor substrate 2 (FRS2) protein. 165.The antibody fusion molecule of claim 164, wherein the target protein is a histone protein, or a fragment thereof. 166.The antibody fusion molecule of claim 165, wherein the histone protein is a histone H3 protein, or fragment thereof, or a histone H4 protein, or fragment thereof. 167.The antibody fusion molecule of claim 166, wherein the histone protein is a histone H3 protein, or fragment thereof. 168.The antibody fusion molecule of claim 166, wherein the histone protein is a histone H4 protein, or fragment thereof. 169.The antibody fusion molecule of claim 166, wherein the first epitope includes a lysine (K) residue that is methylated one or more times. 170.The antibody fusion molecule of claim 169, wherein the lysine (K) residue is trimethylated. 171.The antibody fusion molecule of claim 170, wherein the lysine (K) residue is positioned at amino acid position 9, 27, or 56 of the histone H3 protein, or a fragment thereof.172.The antibody fusion molecule of claim 170, wherein the lysine (K) residue is positioned at amino acid position 20 of the histone H4 protein, or a fragment thereof. 173.The antibody fusion molecule of any one of claims 160-172, wherein B1 comprises: a) a heavy chain complementarity determining region 1 (CDR1), a heavy chainCDR2, a heavy chain CDR3 of a heavy chain variable region (VH) comprising the amino acid sequence of SEQ ID NO: 6; and / or a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a light chain variable region (VL) comprising the amino acid sequence of SEQ ID NO: 1; or b) a heavy chain complementarity determining region 1 (CDR1), a heavy chainCDR2, a heavy chain CDR3 of a heavy chain variable region (VH) comprising the amino acid sequence of SEQ ID NO: 6; and / or a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a light chain variable region (VL) comprising the amino acid sequence of SEQ ID NO:

2. 174.The antibody fusion molecule of claim 173, wherein B1 comprises a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 7, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 8, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO:

9. 175.The antibody fusion molecule of claim 173 or 174, wherein B1 comprises a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 3, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 4, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO:

5. 176.The antibody fusion molecule of any one of claims 173-175, wherein B1 comprises a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 7, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 8, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 9; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 3, a light chain CDR2 comprising theamino acid sequence of SEQ ID NO: 4, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO:

5. 177.The antibody fusion molecule of any one of claims 173-176, wherein B1 comprises a VH comprising an amino acid sequence of SEQ ID NO: 6, and a VL comprising an amino acid sequence of SEQ ID NO: 1 or 2. 178.The antibody fusion molecule of any one of claims 173-177, wherein B2 comprises a heavy chain complementarity determining region 1 (CDR1), a heavy chain CDR2, a heavy chain CDR3 of a heavy chain variable region (VH) comprising the amino acid sequence of SEQ ID NO: 25, 43, 54, 63, 73, 80, 84, 89, 93, 108, 115, 124, 127, 129, or 131; and / or a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a light chain variable region (VL) comprising the amino acid sequence of SEQ ID NO: 21, 41, 52, 61, 71, 78, 82, 87, 91, 103, 112, 117, or 122. 179.The antibody fusion molecule of claim 178, wherein B2 comprises: a) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 25, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 21; b) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 43, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 41; c) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 54, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 52; d) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 63, and a light chain CDR1, alight chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 61;e) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 73, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71;f) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 80, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 78;g) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 84, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 82;h) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 89, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 87;i) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 93, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 91;j) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 93, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 103;k) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 93, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71;l) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 108, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71;m) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 93, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 112;n) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 115, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71;o) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 93, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 117;p) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 124, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 122;q) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 127, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 122;r) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 129, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 122; ors) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 131, and a light chain CDR1,a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO:

122. 180.The antibody fusion molecule of claim 178 or 179, wherein B2 comprises: a) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 26, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 28; b) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 46; c) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 26, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 55; d) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 65; e) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 74, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76; f) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76; g) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 74, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 85; h) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76; i) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95;j) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; k) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 125; or l) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO:

132. 181.The antibody fusion molecule of any one of claims 178-180, wherein B2 comprises: a) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 24; b) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 42; c) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 53; d) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 62; e) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; f) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 79;g) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 83; h) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 88; i) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 92; j) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 104; k) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 113; l) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 118; or m) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO:

123. 182.The antibody fusion molecule of any one of claims 178-181, wherein B2 comprises: a) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 26, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 28; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 24; b) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and aheavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 46; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 42;c) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 26, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 55; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 53;d) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 65; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 62;e) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 74, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72;f) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 79;g) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 74, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 85; and alight chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 83;h) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 88;i) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 92;j) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 104;k) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72;l) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a lightchain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 113; m) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; n) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 118; o) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 125; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 123; or p) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 132; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO:

123. 183.The antibody fusion molecule of any one of claims 178-182, wherein B2 comprises a VH comprising an amino acid sequence of SEQ ID NO: 25, 43, 54, 63, 73, 80, 84, 89, 93, 108, 115, 124, 127, 129, or 131; and / or a VL comprising an amino acid sequence of SEQ ID NO: 21, 41, 52, 61, 71, 78, 82, 87, 91, 103, 112, 117, or 122.184.The antibody fusion molecule of any one of claims 178-183, wherein B2 comprises: a) a VH comprising an amino acid sequence of SEQ ID NO: 25, and a VLcomprising an amino acid sequence of SEQ ID NO: 21; b) a VH comprising an amino acid sequence of SEQ ID NO: 43, and a VLcomprising an amino acid sequence of SEQ ID NO: 41; c) a VH comprising an amino acid sequence of SEQ ID NO: 54, and a VLcomprising an amino acid sequence of SEQ ID NO: 52; d) a VH comprising an amino acid sequence of SEQ ID NO: 63, and a VLcomprising an amino acid sequence of SEQ ID NO: 61; e) a VH comprising an amino acid sequence of SEQ ID NO: 73, and a VLcomprising an amino acid sequence of SEQ ID NO: 71; f) a VH comprising an amino acid sequence of SEQ ID NO: 80, and a VLcomprising an amino acid sequence of SEQ ID NO: 78; g) a VH comprising an amino acid sequence of SEQ ID NO: 84, and a VLcomprising an amino acid sequence of SEQ ID NO: 82; h) a VH comprising an amino acid sequence of SEQ ID NO: 89, and a VLcomprising an amino acid sequence of SEQ ID NO: 87; i) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VLcomprising an amino acid sequence of SEQ ID NO: 91; j) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VLcomprising an amino acid sequence of SEQ ID NO: 103; k) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VLcomprising an amino acid sequence of SEQ ID NO: 71; l) a VH comprising an amino acid sequence of SEQ ID NO: 108, and a VLcomprising an amino acid sequence of SEQ ID NO: 71; m) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VLcomprising an amino acid sequence of SEQ ID NO: 112; n) a VH comprising an amino acid sequence of SEQ ID NO: 115, and a VLcomprising an amino acid sequence of SEQ ID NO: 71;o) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VLcomprising an amino acid sequence of SEQ ID NO: 117; p) a VH comprising an amino acid sequence of SEQ ID NO: 124, and a VLcomprising an amino acid sequence of SEQ ID NO: 122; q) a VH comprising an amino acid sequence of SEQ ID NO: 127, and a VLcomprising an amino acid sequence of SEQ ID NO: 122; r) a VH comprising an amino acid sequence of SEQ ID NO: 129, and a VLcomprising an amino acid sequence of SEQ ID NO: 122; or s) a VH comprising an amino acid sequence of SEQ ID NO: 131, and a VLcomprising an amino acid sequence of SEQ ID NO:

122. 185.The antibody fusion molecule of any one of claims 166-184, wherein the histone H3 protein consists of the amino acid sequence of any one of SEQ ID NOs: 240-247 and the histone H4 protein consists of the amino acid sequence of SEQ ID NO:

248. 186.The antibody fusion molecule of claim 164, wherein the target protein is a platelet- derived growth factor receptor beta (PDGFRb) protein, a breakpoint cluster region (BCR) protein, a protein tyrosine phosphatase (PTPN11) protein, or a fibroblast growth factor receptor substrate 2 (FRS2) protein. 187.The antibody fusion molecule of claim 186, wherein the target protein is a platelet- derived growth factor receptor beta (PDGFRb) protein, or a fragment thereof, or a breakpoint cluster region (BCR) protein, or a fragment thereof. 188.The antibody fusion molecule of claim 186, wherein the first epitope includes a tyrosine (Y) residue that is phosphorylated once. 189.The antibody fusion molecule of claim 188, wherein the target protein is a platelet- derived growth factor receptor beta (PDGFRb) protein, or a fragment thereof, and the tyrosine (Y) residue is positioned at amino acid position 716 of the PDGFRb protein, or a fragment thereof.190.The antibody fusion molecule of claim 188, wherein the target protein is a breakpoint cluster region (BCR) protein, or a fragment thereof, and the tyrosine (Y) residue is positioned at amino acid position 177 of the BCR protein, or a fragment thereof. 191.The antibody fusion molecule of claim 188, wherein the target protein is a protein tyrosine phosphatase (PTPN11) protein, or a fragment thereof, and the tyrosine (Y) residue is positioned at amino acid position 580 of the PTPN11 protein, or a fragment thereof. 192.The antibody fusion molecule of claim 188, wherein the target protein is a fibroblast growth factor receptor substrate 2 (FRS2) protein, or a fragment thereof, and the tyrosine (Y) residue is positioned at amino acid position 196 of the FRS2 protein, or a fragment thereof. 193.The antibody fusion molecule of any one of claims 160-164 and 186-192, wherein B1 comprises a heavy chain complementarity determining region 1 (CDR1), a heavy chain CDR2, a heavy chain CDR3 of a heavy chain variable region (VH) comprising the amino acid sequence of SEQ ID NO: 138; and / or a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a light chain variable region (VL) comprising the amino acid sequence of SEQ ID NO: 134 or 148. 194.The antibody fusion molecule of claim 193, wherein B1 comprises a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 139, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 140, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO:

141. 195.The antibody fusion molecule of claim 193 or 194, wherein B1 comprises a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 135, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 136, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 137.196.The antibody fusion molecule of any one of claims 193-195, wherein B1 comprises a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 139, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 140, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 141; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 135, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 136, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO:

137. 197.The antibody fusion molecule of any one of claims 193-196, wherein B1 comprises a VH comprising an amino acid sequence of SEQ ID NO: 138, and a VL comprising an amino acid sequence of SEQ ID NO: 134 or 148. 198.The antibody fusion molecule of any one of claims 193-197, wherein B2 comprises a heavy chain complementarity determining region 1 (CDR1), a heavy chain CDR2, a heavy chain CDR3 of a heavy chain variable region (VH) comprising the amino acid sequence of SEQ ID NO: 144, 152, 156, 162, 167, 173, or 178; and / or a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a light chain variable region (VL) comprising the amino acid sequence of SEQ ID NO: 71, 151, 160, 165, 172, 176, or 180. 199.The antibody fusion molecule of claim 198, wherein B2 comprises: a) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 144, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71; b) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 152, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 151; c) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 156, and a light chain CDR1,a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71; d) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 162, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 160; e) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 167, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 165; f) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 173, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 172; g) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 178, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 176; or h) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 167, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO:

180. 200.The antibody fusion molecule of claim 198 or 199, wherein B2 comprises: a) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 145, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 146; b) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 145, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 153;c) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 157, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 146; d) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 157, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 153; or e) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 168, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 169, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO:

170. 201.The antibody fusion molecule of any one of claims 198-200, wherein B2 comprises: a) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; b) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 161; c) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 166; d) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 177; or e) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO:

181. 202.The antibody fusion molecule of any one of claims 198-201, wherein B2 comprises: a) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 145, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 146;and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72;b) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 145, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 153; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72;c) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 157, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 146; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72;d) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 157, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 153; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 161;e) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 168, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 169, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 170; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 166;f) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 168, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 169, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 170; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 177; or g) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 168, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 169, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 170; or and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO:

181. 203.The antibody fusion molecule of any one of claims 198-202, wherein B2 comprises a VH comprising an amino acid sequence of SEQ ID NO: 144, 152, 156, 162, 167, 173, or 178; and / or a VL comprising an amino acid sequence of SEQ ID NO: 71, 151, 160, 165, 172, 176, or 180. 204.The antibody fusion molecule of any one of claims 198-203, wherein B2 comprises: a) a VH comprising an amino acid sequence of SEQ ID NO: 144, and a VLcomprising an amino acid sequence of SEQ ID NO: 71; b) a VH comprising an amino acid sequence of SEQ ID NO: 152, and a VLcomprising an amino acid sequence of SEQ ID NO: 151; c) a VH comprising an amino acid sequence of SEQ ID NO: 156, and a VLcomprising an amino acid sequence of SEQ ID NO: 71; d) a VH comprising an amino acid sequence of SEQ ID NO: 162, and a VLcomprising an amino acid sequence of SEQ ID NO: 160; e) a VH comprising an amino acid sequence of SEQ ID NO: 167, and a VLcomprising an amino acid sequence of SEQ ID NO: 165; f) a VH comprising an amino acid sequence of SEQ ID NO: 173, and a VLcomprising an amino acid sequence of SEQ ID NO: 172; g) a VH comprising an amino acid sequence of SEQ ID NO: 178, and a VLcomprising an amino acid sequence of SEQ ID NO: 176; or h) a VH comprising an amino acid sequence of SEQ ID NO: 167, and a VLcomprising an amino acid sequence of SEQ ID NO: 180.205.The antibody fusion molecule of any one of claims 186-204, wherein the platelet-derived growth factor receptor beta (PDGFRb) protein consists of the amino acid sequence of SEQ ID NO: 249, the breakpoint cluster region (BCR) protein consists of the amino acid sequence of SEQ ID NO: 250, the protein tyrosine phosphatase (PTPN11) protein consists of the amino acid sequence of SEQ ID NO: 251, and the fibroblast growth factor receptor substrate 2 (FRS2) protein consists of the amino acid sequence of SEQ ID NO: 252.

206. The antibody fusion molecule of any one of claims 160-205, wherein the first linkersequence and / or the second linker sequence comprises the amino acid sequence GILGSGGGGSGGGGSGGGGS (SEQ ID NO: 15) or GILSGSSSSGSSSSGSSSSG (SEQ ID NO: 32). 207.The antibody fusion molecule of any one of claims 160-206, wherein the third linker sequence is 15-30 amino acids in length. 208.The antibody fusion molecule of claim 207, wherein the third linker sequence comprises the amino acid sequence (SSSSG)3-SS (SEQ ID NO: 31), (SSSSG)4-SS (SEQ ID NO: 34), or (SSSSG)5-SS (SEQ ID NO: 35). 209.The antibody fusion molecule of any one of claims 160-208, wherein the fourth linker210.The antibody fusion molecule of any one of claims 160-209, wherein the anchoring protein is Aga2 anchoring protein.211.The antibody fusion molecule of claim 210, wherein the Aga2 anchoring protein comprises the amino acid sequence212.The antibody fusion molecule of any one of claims 160-211, wherein the cell is a yeast cell. 213.The antibody fusion molecule of any one of claims 160-212, comprising the amino acid sequence of SEQ ID NO: 38, 39, 40, 49, 50, 51, 58, 59, 60, 68, 69, 70, 77, 81, 86, 90, 96, 105, 106, 109, 114, 116, 119, 126, 128, 130, 133, 149, 154, 158, 163, 171, 174, 179, or 182, or an amino acid sequence having at least 75% identity thereto. 214.A multispecific antibody or an antigen-binding fragment thereof comprising: a) a first binding unit (B1) comprising a first scFv, said first scFv comprising a firstantigen-binding domain (“ABD1”) that specifically binds to a first epitope of a target protein, wherein the first epitope includes an amino acid residue harboring one or more of a post-translational modification (PTM); and b) a second binding unit (B2) comprising a second scFv, said second scFv comprisinga second antigen-binding domain (“ABD2”) that specifically binds to both the first binding unit (B1) and a second epitope of the target protein, wherein the second epitope does not include the PTM; wherein: (i) the variable regions of the first scFv are connected by a first linker sequence andthe variable regions of the second scFv are connected by a second linker sequence; (ii) each of the first scFv and the second scFv is operably linked to an Fc domain via athird linker sequence, said third linker sequence being 10 to 40 amino acids in length; (iii) a hinge sequence separates the third linker sequence and the Fc domain(s); and(iv) one of the Fc domains comprises a knob mutation and the other of the Fc domains comprises a hole mutation. 215.The multispecific antibody or an antigen-binding fragment thereof of claim 214, wherein the PTM is selected from methylation, phosphorylation, acetylation, ubiquitination, glycosylation, formylation, propinylation, butyrylation, crotonylation, benzoylation, 2- hydroxyisobutyrylation, hydroxybutyrylation, lactylation, malonylation, succinylation, glutarylation, hydroxylation, sumoylation, ufmylation, biotinylation, serotonylation, dopaminylation, isomerization, myristoylation, sulfation, nitrosylation, ADP-ribosylation, prenylation, palmitoylation, deamidation, and proteolytic cleavage. 216.The multispecific antibody or an antigen-binding fragment thereof of claim 215, wherein the PTM is methylation or phosphorylation. 217.The multispecific antibody or an antigen-binding fragment thereof of any one of claims 214-216, wherein the PTM is comprised within a flexible, disordered region of the target protein that does not form a fixed three-dimensional (3D) structure. 218.The multispecific antibody or an antigen-binding fragment thereof of any one of claims 214-217, wherein the target protein is a histone protein, a platelet-derived growth factor receptor beta (PDGFRb) protein, a breakpoint cluster region (BCR) protein, a protein tyrosine phosphatase (PTPN11) protein, or a fibroblast growth factor receptor substrate 2 (FRS2) protein. 219.The multispecific antibody or an antigen-binding fragment thereof of claim 218, wherein the target protein is a histone protein, or a fragment thereof. 220.The multispecific antibody or an antigen-binding fragment thereof of claim 219, wherein the histone protein is a histone H3 protein, or fragment thereof, or a histone H4 protein, or fragment thereof.221.The multispecific antibody or an antigen-binding fragment thereof of claim 220, wherein the histone protein is a histone H3 protein, or fragment thereof. 222.The multispecific antibody or an antigen-binding fragment thereof of claim 220, wherein the histone protein is a histone H4 protein, or fragment thereof. 223.The multispecific antibody or an antigen-binding fragment thereof of claim 220, wherein the first epitope includes a lysine (K) residue that is methylated one or more times. 224.The multispecific antibody or an antigen-binding fragment thereof of claim 223, wherein the lysine (K) residue is trimethylated. 225.The multispecific antibody or an antigen-binding fragment thereof of claim 224, wherein the lysine (K) residue is positioned at amino acid position 9, 27, or 56 of the histone H3 protein, or a fragment thereof. 226.The multispecific antibody or an antigen-binding fragment thereof of claim 224, wherein the lysine (K) residue is positioned at amino acid position 20 of the histone H4 protein, or a fragment thereof. 227.The multispecific antibody or an antigen-binding fragment thereof of any one of claims 214-226, wherein B1 comprises: a) a heavy chain complementarity determining region 1 (CDR1), a heavy chainCDR2, a heavy chain CDR3 of a heavy chain variable region (VH) comprising the amino acid sequence of SEQ ID NO: 6; and / or a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a light chain variable region (VL) comprising the amino acid sequence of SEQ ID NO: 1; or b) a heavy chain complementarity determining region 1 (CDR1), a heavy chainCDR2, a heavy chain CDR3 of a heavy chain variable region (VH) comprising the amino acid sequence of SEQ ID NO: 6; and / or a light chain CDR1, a lightchain CDR2, and a light chain CDR3 of a light chain variable region (VL) comprising the amino acid sequence of SEQ ID NO:

2. 228.The multispecific antibody or an antigen-binding fragment thereof of claim 227, wherein B1 comprises a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 7, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 8, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO:

9. 229.The multispecific antibody or an antigen-binding fragment thereof of claim 227 or 228, wherein B1 comprises a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 3, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 4, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO:

5. 230.The multispecific antibody or an antigen-binding fragment thereof of any one of claims 227-229, wherein B1 comprises a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 7, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 8, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 9; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 3, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 4, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO:

5. 231.The multispecific antibody or an antigen-binding fragment thereof of any one of claims 227-230, wherein B1 comprises a VH comprising an amino acid sequence of SEQ ID NO: 6, and a VL comprising an amino acid sequence of SEQ ID NO: 1 or 2. 232.The multispecific antibody or an antigen-binding fragment thereof of any one of claims 227-231, wherein B2 comprises a heavy chain complementarity determining region 1 (CDR1), a heavy chain CDR2, a heavy chain CDR3 of a heavy chain variable region (VH) comprising the amino acid sequence of SEQ ID NO: 25, 43, 54, 63, 73, 80, 84, 89, 93, 108, 115, 124, 127, 129, or 131; and / or a light chain CDR1, a light chain CDR2, and alight chain CDR3 of a light chain variable region (VL) comprising the amino acid sequence of SEQ ID NO: 21, 41, 52, 61, 71, 78, 82, 87, 91, 103, 112, 117, or 122. 233.The multispecific antibody or an antigen-binding fragment thereof of claim 232, wherein B2 comprises: a) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 25, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 21; b) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 43, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 41; c) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 54, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 52; d) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 63, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 61; e) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 73, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71; f) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 80, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 78; g) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 84, and a light chain CDR1, alight chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 82;h) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 89, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 87;i) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 93, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 91;j) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 93, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 103;k) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 93, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71;l) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 108, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71;m) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 93, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 112;n) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 115, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71;o) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 93, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 117; p) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 124, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 122; q) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 127, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 122; r) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 129, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 122; or s) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 131, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO:

122. 234.The multispecific antibody or an antigen-binding fragment thereof of claim 232 or 233, wherein B2 comprises: a) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 26, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 28; b) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 46;c) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 26, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 55;d) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 65;e) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 74, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76;f) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76;g) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 74, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 85;h) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76;i) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95;j) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95;k) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 125; orl) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 132.235.The multispecific antibody or an antigen-binding fragment thereof of any one of claims 232-234, wherein B2 comprises: a) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 24; b) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 42; c) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 53; d) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 62; e) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; f) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 79; g) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 83; h) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 88; i) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 92;j) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 104; k) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 113; l) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 118; or m) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO:

123. 236.The antibody fusion molecule of any one of claims 232-235, wherein B2 comprises: a) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 26, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 28; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 24; b) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 46; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 42; c) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 26, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 55; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a lightchain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 53;d) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 65; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 62;e) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 74, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72;f) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 79;g) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 74, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 75, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 85; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 83;h) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 27, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 76; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a lightchain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 88;i) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 92;j) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 104;k) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72;l) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 113;m) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 44, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a lightchain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; n) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 118; o) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 125; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 123; or p) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 45, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 132; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO:

123. 237.The multispecific antibody or an antigen-binding fragment thereof of claim 236, wherein B2 comprises: a) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 92; b) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and aheavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; or c) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 94, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 95; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO:

118. 238.The multispecific antibody or an antigen-binding fragment thereof of one of claims 232- 237, wherein B2 comprises a VH comprising an amino acid sequence of SEQ ID NO: 25, 43, 54, 63, 73, 80, 84, 89, 93, 108, 115, 124, 127, 129, or 131; and / or a VL comprising an amino acid sequence of SEQ ID NO: 21, 41, 52, 61, 71, 78, 82, 87, 91, 103, 112, 117, or 122. 239.The multispecific antibody or an antigen-binding fragment thereof of claim 238, wherein B2 comprises a VH comprising an amino acid sequence of SEQ ID NO: 93 or 108; and / or a VL comprising an amino acid sequence of SEQ ID NO: 71, 91, or 117. 240.The multispecific antibody or an antigen-binding fragment thereof of claim 238, wherein B2 comprises: a) a VH comprising an amino acid sequence of SEQ ID NO: 25, and a VLcomprising an amino acid sequence of SEQ ID NO: 21; b) a VH comprising an amino acid sequence of SEQ ID NO: 43, and a VLcomprising an amino acid sequence of SEQ ID NO: 41; c) a VH comprising an amino acid sequence of SEQ ID NO: 54, and a VLcomprising an amino acid sequence of SEQ ID NO: 52; d) a VH comprising an amino acid sequence of SEQ ID NO: 63, and a VLcomprising an amino acid sequence of SEQ ID NO: 61;e) a VH comprising an amino acid sequence of SEQ ID NO: 73, and a VLcomprising an amino acid sequence of SEQ ID NO: 71;f) a VH comprising an amino acid sequence of SEQ ID NO: 80, and a VLcomprising an amino acid sequence of SEQ ID NO: 78;g) a VH comprising an amino acid sequence of SEQ ID NO: 84, and a VLcomprising an amino acid sequence of SEQ ID NO: 82;h) a VH comprising an amino acid sequence of SEQ ID NO: 89, and a VLcomprising an amino acid sequence of SEQ ID NO: 87;i) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VLcomprising an amino acid sequence of SEQ ID NO: 91;j) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VLcomprising an amino acid sequence of SEQ ID NO: 103;k) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VLcomprising an amino acid sequence of SEQ ID NO: 71;l) a VH comprising an amino acid sequence of SEQ ID NO: 108, and a VLcomprising an amino acid sequence of SEQ ID NO: 71;m) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VLcomprising an amino acid sequence of SEQ ID NO: 112;n) a VH comprising an amino acid sequence of SEQ ID NO: 115, and a VLcomprising an amino acid sequence of SEQ ID NO: 71;o) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VLcomprising an amino acid sequence of SEQ ID NO: 117;p) a VH comprising an amino acid sequence of SEQ ID NO: 124, and a VLcomprising an amino acid sequence of SEQ ID NO: 122;q) a VH comprising an amino acid sequence of SEQ ID NO: 127, and a VLcomprising an amino acid sequence of SEQ ID NO: 122;r) a VH comprising an amino acid sequence of SEQ ID NO: 129, and a VLcomprising an amino acid sequence of SEQ ID NO: 122; ors) a VH comprising an amino acid sequence of SEQ ID NO: 131, and a VLcomprising an amino acid sequence of SEQ ID NO: 122.241.The multispecific antibody or an antigen-binding fragment thereof of claim 240, wherein B2 comprises: a) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VLcomprising an amino acid sequence of SEQ ID NO: 91; b) a VH comprising an amino acid sequence of SEQ ID NO: 108, and a VLcomprising an amino acid sequence of SEQ ID NO: 71; or c) a VH comprising an amino acid sequence of SEQ ID NO: 93, and a VLcomprising an amino acid sequence of SEQ ID NO:

117. 242.The multispecific antibody or an antigen-binding fragment thereof of any one of claims 220-241, wherein the histone H3 protein consists of the amino acid sequence of any one of SEQ ID NOs: 240-247 and the histone H4 protein consists of the amino acid sequence of SEQ ID NO:

248. 243.The multispecific antibody or an antigen-binding fragment thereof of claim 218, wherein the target protein is a platelet-derived growth factor receptor beta (PDGFRb) protein, a breakpoint cluster region (BCR) protein, a protein tyrosine phosphatase (PTPN11) protein, or a fibroblast growth factor receptor substrate 2 (FRS2) protein. 244.The multispecific antibody or an antigen-binding fragment thereof of claim 243, wherein the target protein is a platelet-derived growth factor receptor beta (PDGFRb) protein, or a fragment thereof, or a breakpoint cluster region (BCR) protein, or a fragment thereof. 245.The multispecific antibody or an antigen-binding fragment thereof of claim 243, wherein the first epitope includes a tyrosine (Y) residue that is phosphorylated once. 246.The multispecific antibody or an antigen-binding fragment thereof of claim 245, wherein the target protein is a platelet-derived growth factor receptor beta (PDGFRb) protein, or a fragment thereof, and the tyrosine (Y) residue is positioned at amino acid position 716 of the PDGFRb protein, or a fragment thereof.247.The multispecific antibody or an antigen-binding fragment thereof of claim 245, wherein the target protein is a breakpoint cluster region (BCR) protein, or a fragment thereof, and the tyrosine (Y) residue is positioned at amino acid position 177 of the BCR protein, or a fragment thereof. 248.The multispecific antibody or an antigen-binding fragment thereof of claim 245, wherein the target protein is a protein tyrosine phosphatase (PTPN11) protein, or a fragment thereof, and the tyrosine (Y) residue is positioned at amino acid position 580 of the PTPN11 protein, or a fragment thereof. 249.The multispecific antibody or an antigen-binding fragment thereof of claim 245, wherein the target protein is a fibroblast growth factor receptor substrate 2 (FRS2) protein, or a fragment thereof, and the tyrosine (Y) residue is positioned at amino acid position 196 of the FRS2 protein, or a fragment thereof. 250.The multispecific antibody or an antigen-binding fragment thereof of any one of claims 214-218 and 243-249, wherein B1 comprises a heavy chain complementarity determining region 1 (CDR1), a heavy chain CDR2, a heavy chain CDR3 of a heavy chain variable region (VH) comprising the amino acid sequence of SEQ ID NO: 138; and / or a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a light chain variable region (VL) comprising the amino acid sequence of SEQ ID NO: 134 or 148. 251.The multispecific antibody or an antigen-binding fragment thereof of claim 250, wherein B1 comprises a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 139, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 140, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO:

141. 252.The multispecific antibody or an antigen-binding fragment thereof of claim 250 or 251, wherein B1 comprises a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 135, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 136, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 137.253.The multispecific antibody or an antigen-binding fragment thereof of any one of claims 250-252, wherein B1 comprises a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 139, a heavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 140, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 141; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 135, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 136, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO:

137. 254.The multispecific antibody or an antigen-binding fragment thereof of any one of claims 250-253, wherein B1 comprises a VH comprising an amino acid sequence of SEQ ID NO: 138, and a VL comprising an amino acid sequence of SEQ ID NO: 134 or 148. 255.The multispecific antibody or an antigen-binding fragment thereof of any one of claims 214-218 and 243-254, wherein B2 comprises a heavy chain complementarity determining region 1 (CDR1), a heavy chain CDR2, a heavy chain CDR3 of a heavy chain variable region (VH) comprising the amino acid sequence of SEQ ID NO: 144, 152, 156, 162, 167, 173, or 178; and / or a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a light chain variable region (VL) comprising the amino acid sequence of SEQ ID NO: 71, 151, 160, 165, 172, 176, or 180. 256.The multispecific antibody or an antigen-binding fragment thereof of claim 255, wherein B2 comprises: a) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 144, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71; b) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 152, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 151;c) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 156, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 71; d) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 162, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 160; e) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 167, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 165; f) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 173, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 172; g) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 178, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO: 176; or h) a heavy chain CDR1, a heavy chain CDR2, a heavy chain CDR3 of a VHcomprising an amino acid sequence of SEQ ID NO: 167, and a light chain CDR1, a light chain CDR2, and a light chain CDR3 of a VL comprising an amino acid sequence of SEQ ID NO:

180. 257.The multispecific antibody or an antigen-binding fragment thereof of claim 255 or 256, wherein B2 comprises: a) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 145, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 146;b) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 145, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 153; c) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 157, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 146; d) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 157, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 153; or e) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 168, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 169, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO:

170. 258.The multispecific antibody or an antigen-binding fragment thereof of any one of claims 255-257, wherein B2 comprises: a) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; b) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 161; c) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 166; d) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 177; or e) a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 181.259.The multispecific antibody or an antigen-binding fragment thereof of any one of claims 255-258, wherein B2 comprises: a) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 145, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 146; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; b) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 145, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 153; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; c) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 157, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 146; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; d) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 157, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 153; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 161; e) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 168, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 169, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 170; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, alight chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 166; f) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 168, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 169, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 170; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 177; or g) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 168, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 169, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 170; or and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO:

181. 260.The multispecific antibody or an antigen-binding fragment thereof of claim 259, wherein B2 comprises: a) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 145, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 146; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; b) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 145, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 153; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; c) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 157, anda heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 146; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 72; d) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 64, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 157, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 153; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 161; e) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 168, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 169, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 170; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO: 166; or f) a heavy chain CDR1 comprising the amino acid sequence of SEQ ID NO: 168, aheavy chain CDR2 comprising the amino acid sequence of SEQ ID NO: 169, and a heavy chain CDR3 comprising the amino acid sequence of SEQ ID NO: 170; and a light chain CDR1 comprising the amino acid sequence of SEQ ID NO: 22, a light chain CDR2 comprising the amino acid sequence of SEQ ID NO: 23, and a light chain CDR3 comprising the amino acid sequence of SEQ ID NO:

181. 261.The multispecific antibody or an antigen-binding fragment thereof of any one of claims 255-260, wherein B2 comprises a VH comprising an amino acid sequence of SEQ ID NO: 144, 152, 156, 162, 167, 173, or 178; and / or a VL comprising an amino acid sequence of SEQ ID NO: 71, 151, 160, 165, 172, 176, or 180. 262.The multispecific antibody or an antigen-binding fragment thereof of claim 261, wherein B2 comprises a VH comprising an amino acid sequence of SEQ ID NO: 144, 152, 156,162, 167, or 173; and / or a VL comprising an amino acid sequence of SEQ ID NO: 71, 151, 160, 172, or 180. 263.The multispecific antibody or an antigen-binding fragment thereof of any one of claims 255-262, wherein B2 comprises: a) a VH comprising an amino acid sequence of SEQ ID NO: 144, and a VLcomprising an amino acid sequence of SEQ ID NO: 71; b) a VH comprising an amino acid sequence of SEQ ID NO: 152, and a VLcomprising an amino acid sequence of SEQ ID NO: 151; c) a VH comprising an amino acid sequence of SEQ ID NO: 156, and a VLcomprising an amino acid sequence of SEQ ID NO: 71; d) a VH comprising an amino acid sequence of SEQ ID NO: 162, and a VLcomprising an amino acid sequence of SEQ ID NO: 160; e) a VH comprising an amino acid sequence of SEQ ID NO: 167, and a VLcomprising an amino acid sequence of SEQ ID NO: 165; f) a VH comprising an amino acid sequence of SEQ ID NO: 173, and a VLcomprising an amino acid sequence of SEQ ID NO: 172; g) a VH comprising an amino acid sequence of SEQ ID NO: 178, and a VLcomprising an amino acid sequence of SEQ ID NO: 176; or h) a VH comprising an amino acid sequence of SEQ ID NO: 167, and a VLcomprising an amino acid sequence of SEQ ID NO:

180. 264.The multispecific antibody or an antigen-binding fragment thereof of claim 263, wherein B2 comprises: a) a VH comprising an amino acid sequence of SEQ ID NO: 144, and a VLcomprising an amino acid sequence of SEQ ID NO: 71; b) a VH comprising an amino acid sequence of SEQ ID NO: 152, and a VLcomprising an amino acid sequence of SEQ ID NO: 151; c) a VH comprising an amino acid sequence of SEQ ID NO: 156, and a VLcomprising an amino acid sequence of SEQ ID NO: 71;d) a VH comprising an amino acid sequence of SEQ ID NO: 162, and a VLcomprising an amino acid sequence of SEQ ID NO: 160; e) a VH comprising an amino acid sequence of SEQ ID NO: 173, and a VLcomprising an amino acid sequence of SEQ ID NO: 172; or f) a VH comprising an amino acid sequence of SEQ ID NO: 167, and a VLcomprising an amino acid sequence of SEQ ID NO:

180. 265.The multispecific antibody or an antigen-binding fragment thereof of any one of claims 243-264, wherein the platelet-derived growth factor receptor beta (PDGFRb) protein consists of the amino acid sequence of SEQ ID NO: 249, the breakpoint cluster region (BCR) protein consists of the amino acid sequence of SEQ ID NO: 250, the protein tyrosine phosphatase (PTPN11) protein consists of the amino acid sequence of SEQ ID NO: 251, and the fibroblast growth factor receptor substrate 2 (FRS2) protein consists of the amino acid sequence of SEQ ID NO: 252.

266. The multispecific antibody or an antigen-binding fragment thereof of any one of claims214-265, wherein the first linker sequence and / or the second linker sequence comprises the amino acid sequence GILGSGGGGSGGGGSGGGGS (SEQ ID NO: 15) or GILSGSSSSGSSSSGSSSSG (SEQ ID NO: 32). 267.The multispecific antibody or an antigen-binding fragment thereof of any one of claims 214-266, wherein the third linker sequence is 15-30 amino acids in length. 268.The multispecific antibody or an antigen-binding fragment thereof of claim 267, wherein the third linker sequence comprises the amino acid sequence (SSSSG)3-SS (SEQ ID NO: 31), (SSSSG)4-SS (SEQ ID NO: 34), or (SSSSG)5-SS (SEQ ID NO: 35). 269.The multispecific antibody or an antigen-binding fragment thereof of any one of claims 214-268, wherein the hinge sequence comprises the amino acid sequence GCKPCICT (SEQ ID NO: 17).270.The multispecific antibody or an antigen-binding fragment thereof of any one of claims 214-269, wherein one or both of the Fc domain(s) are derived from an IgG antibody. 271.The multispecific antibody or an antigen-binding fragment thereof of claim 270, wherein the IgG antibody is of IgG1, IgG2, IgG3, or IgG4 subclass. 272.The multispecific antibody or an antigen-binding fragment thereof of claim 271, wherein the IgG antibody is of IgG1 subclass. 273.The multispecific antibody or an antigen-binding fragment thereof of claim 272, wherein one or both of the Fc domain(s) comprise a S239C mutation. 274.The multispecific antibody or an antigen-binding fragment thereof of claim 272 or 273, wherein the Fc domains dimerize to form an Fc heterodimer. 275.The multispecific antibody or an antigen-binding fragment thereof of claim 274, wherein the Fc domains in the Fc heterodimer comprise knob-in-hole mutations as compared to a wild-type Fc domain.

276. The multispecific antibody or an antigen-binding fragment thereof of claim 275, whereinone Fc domain in the Fc heterodimer comprises amino acid substitutions P354C and T366W (according to EU numbering) as compared to a wild-type Fc domain, and the other Fc domain in the Fc heterodimer comprises amino acid substitutions Y349C, T366S, M368A, and Y407V (according to EU numbering) as compared to a wild-type Fc domain. 277.The multispecific antibody or an antigen-binding fragment thereof of any one of claims 274-276, wherein one of the Fc domains in the Fc heterodimer comprises the amino acid sequence of SEQ ID NO: 187, and the other of the Fc domains in the Fc heterodimer comprises the amino acid sequence of SEQ ID NO: 188.278.The multispecific antibody or antigen-binding fragment thereof of any one of claims 214- 277, comprising two polypeptide chains, wherein the first polypeptide chain comprises the amino acid sequence of SEQ ID NO: 20 or 143, or an amino acid sequence having at least 75% identity thereto, and the second polypeptide chain comprises the amino acid sequence of SEQ ID NO: 102, 111, 121, 150, 155, 159, 164, 175, or 183, or an amino acid sequence having at least 75% identity thereto. 279.The multispecific antibody or antigen-binding fragment thereof of claim 278, comprising: a) a first polypeptide chain comprising an amino acid sequence of SEQ ID NO: 20,or an amino acid sequence having at least 75% identity thereto; and a second comprising an amino acid sequence of SEQ ID NO: 102; or an amino acid sequence having at least 75% identity thereto; b) a first polypeptide chain comprising an amino acid sequence of SEQ ID NO: 20,or an amino acid sequence having at least 75% identity thereto; and a second comprising an amino acid sequence of SEQ ID NO: 111; or an amino acid sequence having at least 75% identity thereto; c) a first polypeptide chain comprising an amino acid sequence of SEQ ID NO: 20,or an amino acid sequence having at least 75% identity thereto; and a second comprising an amino acid sequence of SEQ ID NO: 121; or an amino acid sequence having at least 75% identity thereto; d) a first polypeptide chain comprising an amino acid sequence of SEQ ID NO: 143,or an amino acid sequence having at least 75% identity thereto; and a second comprising an amino acid sequence of SEQ ID NO: 150; or an amino acid sequence having at least 75% identity thereto; e) a first polypeptide chain comprising an amino acid sequence of SEQ ID NO: 143,or an amino acid sequence having at least 75% identity thereto; and a second comprising an amino acid sequence of SEQ ID NO: 155; or an amino acid sequence having at least 75% identity thereto; f) a first polypeptide chain comprising an amino acid sequence of SEQ ID NO: 143,or an amino acid sequence having at least 75% identity thereto; and a secondcomprising an amino acid sequence of SEQ ID NO: 159; or an amino acid sequence having at least 75% identity thereto; g) a first polypeptide chain comprising an amino acid sequence of SEQ ID NO: 143,or an amino acid sequence having at least 75% identity thereto; and a second comprising an amino acid sequence of SEQ ID NO: 164; or an amino acid sequence having at least 75% identity thereto; h) a first polypeptide chain comprising an amino acid sequence of SEQ ID NO: 143,or an amino acid sequence having at least 75% identity thereto; and a second comprising an amino acid sequence of SEQ ID NO: 175; or an amino acid sequence having at least 75% identity thereto; or i) a first polypeptide chain comprising an amino acid sequence of SEQ ID NO: 143,or an amino acid sequence having at least 75% identity thereto; and a second comprising an amino acid sequence of SEQ ID NO: 183; or an amino acid sequence having at least 75% identity thereto. 280.The antibody fusion molecule of any one of claims 103-213 or the multispecific antibody or antigen-binding fragment thereof of any one of claims 214-279, further comprising one or more of a reporter protein or a protein tag. 281.The antibody fusion molecule or the multispecific antibody or antigen-binding fragment thereof of claim 280, wherein the protein tag is an affinity tag. 282.The antibody fusion molecule or the multispecific antibody or antigen-binding fragment thereof of claim 280, wherein the reporter protein or the protein tag is a V5 epitope tag (V5-tag), an biotinylation tag, a polyhistidine tag (His-tag), a fluorescent protein, a c-myc tag, a glutathione S-transferase (GST) tag, a FLAG tag, an HA tag, an S-tag, a FLASH tag, a SNAP-tag, a streptavidin moiety, a Strep II tag, an HA tag, an L14 tag, a 4C-RGD tag, an LH tag, a protein A, a maltose-binding protein (MBP), an albumin-binding protein, a chitin binding domain, a calmodulin binding peptide, a cellulose binding domain, a biotin moiety, an oligonucleotide (oligo), or a horseradish peroxidase (HRP).283.The antibody fusion molecule or the multispecific antibody or antigen-binding fragment thereof of claim 282, wherein the reporter protein or the protein tag is a V5 epitope tag (V5-tag), a biotinylation tag, or a polyhistidine tag (His-tag). 284.The antibody fusion molecule or the multispecific antibody or antigen-binding fragment thereof of claim 283, wherein the V5-tag comprises the amino acid sequence GKPIPNPLLGLDST (SEQ ID NO: 33). 285.The antibody fusion molecule or the multispecific antibody or antigen-binding fragment thereof of claim 283, wherein the His-tag comprises the amino acid sequence HHHHHH (SEQ ID NO: 99). 286.An antibody conjugate comprising the antibody or combination of antibodies or antigen- binding fragment(s) thereof of any one of claims 1-102, the antibody fusion molecule of any one of claims 103-213, or the multispecific antibody or antigen-binding fragment thereof of any one of claims 214-285, conjugated to a heterologous moiety. 287.The antibody conjugate of claim 286, wherein the heterologous moiety is one or more of a reporter protein or a protein tag capable of being used for molecular detection. 288.The antibody conjugate of claim 287, wherein the protein tag is an affinity tag. 289.The antibody conjugate of claim 287 or 288, wherein the reporter protein or the protein tag is a V5 epitope tag (V5-tag), an biotinylation tag, a polyhistidine tag (His-tag), a fluorescent protein, a c-myc tag, a glutathione S-transferase (GST) tag, a FLAG tag, an HA tag, an S-tag, a FLASH tag, a SNAP-tag, a streptavidin moiety, a Strep II tag, an HA tag, an L14 tag, a 4C-RGD tag, an LH tag, a protein A, a maltose-binding protein (MBP), an albumin-binding protein, a chitin binding domain, a calmodulin binding peptide, a cellulose binding domain, a biotin moiety, an oligonucleotide (oligo), or a horseradish peroxidase (HRP).290.The antibody conjugate of claim 289, wherein the reporter protein or the protein tag is a V5 epitope tag (V5-tag), a biotinylation tag, or a polyhistidine tag (His-tag). 291.The antibody conjugate of claim 289, wherein the reporter protein or the protein tag is a fluorescent protein, an oligonucleotide (oligo), a horseradish peroxidase (HRP), or a biotinylation tag.

292. The antibody conjugate of any one of claims 287-291, wherein the molecular detection isimmunoprecipitation (IP), western blot, dot blot, immunofluorescence (IF), immunohistochemistry (IHC), immunocytochemistry (ICC), enzyme-linked immunosorbent assay (ELISA), or flow cytometry. 293.The antibody conjugate of claim 292, wherein the immunoprecipitation (IP) comprises chromatin immunoprecipitation (ChIP). 294.The antibody conjugate of any one of claims 287-293, wherein the molecular detection occurs in a cell of a cancer or a cellular component thereof. 295.The antibody conjugate of any one of claims 287-294, wherein the molecular detection occurs in vitro. 296.The antibody conjugate of any one of claims 287-294, wherein the molecular detection occurs ex vivo. 297.The antibody conjugate of any one of claims 287-294, wherein the molecular detection occurs in vivo. 298.The antibody conjugate of any one of claims 287-297, wherein the cancer cell is sampled from a subject in need thereof or is in a subject in need thereof.299.The antibody conjugate of any one of claims 296-298, wherein the cancer is a hematologic cancer or solid cancer. 300.The antibody conjugate of claim 299, wherein the hematologic cancer is leukemia. 301.The antibody conjugate of claim 300, wherein the leukemia is acute myeloid leukemia (AML), acute lymphoblastic leukemia (ALL), acute leukemia of ambiguous lineage, chronic myeloid neoplasm, non-Hodgkin lymphoma, Hodgkin lymphoma, chronic leukemia, dendritic / histiocytic neoplasm, or lymphoproliferative disorder. 302.The antibody conjugate of claim 299, wherein the solid cancer is glioma, thyroid cancer, lung cancer, colorectal cancer, head and neck cancer, esophageal cancer, gastric cancer, stomach cancer, liver cancer, pancreatic cancer, renal cancer, urothelial cancer, prostate cancer, testis cancer, breast cancer, cervical cancer, endometrial cancer, ovarian cancer, gallbladder cancer, sarcoma, melanoma, or malignant peripheral nerve sheath tumors (MPNSTs). 303.The antibody conjugate of claim 302, wherein the solid cancer is lung cancer, colorectal cancer, esophageal cancer, stomach cancer, liver cancer, renal cancer, prostate cancer, breast cancer, or malignant peripheral nerve sheath tumors (MPNSTs). 304.The antibody conjugate of any one of claims 287-303, wherein the antibody conjugate is an antibody-drug conjugate (ADC). 305.The antibody conjugate of claim 304, wherein the heterologous moiety is a cytotoxic agent, an siRNA, a radionucleotide, a peptide, or an immune-modulatory agent. 306.The antibody conjugate of any one of claims 298-305, wherein the subject is human. 307.A polynucleotide encoding the antibody or combination of antibodies or antigen-binding fragment(s) thereof of any one of claims 1-102, the antibody fusion molecule of any oneof claims 103-213, or the multispecific antibody or antigen-binding fragment thereof of any one of claims 214-285. 308.A vector comprising the polynucleotide of claim 307. 309.A host cell expressing the antibody or combination of antibodies or antigen-binding fragment(s) thereof of any one of claims 1-102, the antibody fusion molecule of any one of claims 103-213, or the multispecific antibody or antigen-binding fragment thereof of any one of claims 214-285, comprising the polynucleotide of claim 307 or the vector of claim 308. 310.The host cell of claim 309, wherein the cell is a hybridoma. 311.The host cell of claim 309 or 310, wherein the antibody or combination of antibodies or antigen-binding fragment(s) thereof, the antibody fusion molecule, or the multispecific antibody or antigen-binding fragment thereof is recombinantly produced. 312.A method of producing a host cell expressing the antibody or combination of antibodies or antigen-binding fragment(s) thereof of any one of claims 1-102, the antibody fusion molecule of any one of claims 103-213, or the multispecific antibody or antigen-binding fragment thereof of any one of claims 214-285, wherein said method comprises culturing the host cell of any one of claims 309-311, and isolating said antibody or combination of antibodies or antigen-binding fragment(s) thereof, said antibody fusion molecule, or said multispecific antibody or antigen-binding fragment thereof. 313.A pharmaceutical composition comprising the antibody or combination of antibodies or antigen-binding fragment(s) thereof of any one of claims 1-102, the antibody fusion molecule of any one of claims 103-213, the multispecific antibody or antigen-binding fragment thereof of any one of claims 214-285, the antibody conjugate of any one of claims 286-306, the polynucleotide of claim 307, or the vector of claim 308, and a pharmaceutically acceptable carrier or diluent.314.A kit comprising (i) the antibody or combination of antibodies or antigen-binding fragment(s) thereof of any one of claims 1-102, the antibody fusion molecule of any one of claims 103-213, the multispecific antibody or antigen-binding fragment thereof of any one of claims 214-285, the antibody conjugate of any one of claims 286-306, the polynucleotide of claim 307, the vector of claim 308, or the pharmaceutical composition of claim 313, and (ii) packaging for the same. 315.A method for detecting a cell expressing a target protein, said target protein including an amino acid residue harboring one or more of a post-translational modification (PTM), the method comprising contacting the cell with the antibody or combination of antibodies or antigen-binding fragment(s) thereof of any one of claims 1-102, the antibody fusion molecule of any one of claims 103-213, the multispecific antibody or antigen-binding fragment thereof of any one of claims 214-285, or the antibody conjugate of any one of claims 286-306. 316.A method of killing a cell expressing a target protein, said target protein including an amino acid residue harboring one or more of a post-translational modification (PTM), the method comprising contacting the cell with an effective amount of the antibody or combination of antibodies or antigen-binding fragment(s) thereof of any one of claims 1- 102, the antibody fusion molecule of any one of claims 103-213, the multispecific antibody or antigen-binding fragment thereof of any one of claims 214-285, the antibody conjugate of any one of claims 286-306, the polynucleotide of claim 307, the vector of claim 308, or the pharmaceutical composition of claim 313. 317.The method of claims 315 or 316, wherein the PTM is selected from methylation, phosphorylation, acetylation, ubiquitination, glycosylation, formylation, propinylation, butyrylation, crotonylation, benzoylation, 2-hydroxyisobutyrylation, hydroxybutyrylation, lactylation, malonylation, succinylation, glutarylation, hydroxylation, sumoylation, ufmylation, biotinylation, serotonylation, dopaminylation, isomerization, myristoylation,sulfation, nitrosylation, ADP-ribosylation, prenylation, palmitoylation, deamidation, and proteolytic cleavage. 318.The method of claim 317, wherein the PTM is methylation or phosphorylation. 319.The method of any one of claims 315-318, wherein the PTM is comprised within a flexible, disordered region of the target protein that does not form a fixed three- dimensional (3D) structure. 320.The method of any one of claims 315-319, wherein the target protein is a histone protein, a platelet-derived growth factor receptor beta (PDGFRb) protein, a breakpoint cluster region (BCR) protein, a protein tyrosine phosphatase (PTPN11) protein, or a fibroblast growth factor receptor substrate 2 (FRS2) protein. 321.The method of any one of claims 315-320, wherein the cell is a cell of a cancer. 322.The method of any one of claims 315-321, wherein the contacting occurs in vitro. 323.The method of any one of claims 315-321, wherein the contacting occurs ex vivo. 324.The method of any one of claims 315-321, wherein the contacting occurs in vivo. 325.The method of any one of claims 321-324, wherein the cancer cell is sampled from a subject in need thereof or is in a subject in need thereof. 326.A method of treating or preventing a cancer associated with a target protein in a subject in need thereof, said target protein including an amino acid residue harboring one or more of a post-translational modification (PTM), comprising administering to the subject an effective amount of the antibody or combination of antibodies or antigen-binding fragment(s) thereof of any one of claims 1-102, the antibody fusion molecule of any one of claims 103-213, the multispecific antibody or antigen-binding fragment thereof of anyone of claims 214-285, the antibody conjugate of any one of claims 286-306, the polynucleotide of claim 307, the vector of claim 308, or the pharmaceutical composition of claim 313. 327.The method of claim 326, wherein the PTM is selected from methylation, phosphorylation, acetylation, ubiquitination, glycosylation, formylation, propinylation, butyrylation, crotonylation, benzoylation, 2-hydroxyisobutyrylation, hydroxybutyrylation, lactylation, malonylation, succinylation, glutarylation, hydroxylation, sumoylation, ufmylation, biotinylation, serotonylation, dopaminylation, isomerization, myristoylation, sulfation, nitrosylation, ADP-ribosylation, prenylation, palmitoylation, deamidation, and proteolytic cleavage. 328.The method of claim 326 or 327, wherein the PTM is methylation or phosphorylation. 329.The method of any one of claims 326-328, wherein the PTM is comprised within a flexible, disordered region of the target protein that does not form a fixed three- dimensional (3D) structure. 330.The method of any one of claims 326-329, wherein the target protein is a histone protein, a platelet-derived growth factor receptor beta (PDGFRb) protein, a breakpoint cluster region (BCR) protein, a protein tyrosine phosphatase (PTPN11) protein, or a fibroblast growth factor receptor substrate 2 (FRS2) protein. 331.The method of any one of claims 326-330, wherein the cancer is a hematologic cancer or solid cancer. 332.The method of claim 331, wherein the hematologic cancer is leukemia. 333.The method of claim 332, wherein the leukemia is acute myeloid leukemia (AML), acute lymphoblastic leukemia (ALL), acute leukemia of ambiguous lineage, chronic myeloidneoplasm, non-Hodgkin lymphoma, Hodgkin lymphoma, chronic leukemia, dendritic / histiocytic neoplasm, or lymphoproliferative disorder. 334.The method of claim 331, wherein the solid cancer is glioma, thyroid cancer, lung cancer, colorectal cancer, head and neck cancer, esophageal cancer, gastric cancer, stomach cancer, liver cancer, pancreatic cancer, renal cancer, urothelial cancer, prostate cancer, testis cancer, breast cancer, cervical cancer, endometrial cancer, ovarian cancer, gallbladder cancer, sarcoma, melanoma, or malignant peripheral nerve sheath tumors (MPNSTs). 335.The method of claim 334, wherein the solid cancer is lung cancer, colorectal cancer, esophageal cancer, stomach cancer, liver cancer, renal cancer, prostate cancer, breast cancer, or malignant peripheral nerve sheath tumors (MPNSTs). 336.The method of any one of claims 326-335, wherein the method further comprises administering one or more additional therapeutic agents. 337.The method of claim 336, wherein the one or more additional therapeutic agents comprise one or more chemotherapeutic agents, targeted therapies, stem cell transplantation, radiotherapy, or a combination thereof. 338.The method of claim 337, wherein the one or more chemotherapeutic agents comprises an anthracycline, cytarabine, all-trans-retinoic acid, arsenic trioxide, a hypomethylating agent, a BH-3 mimetic, temozolamide, hydroxyurea, 6-thioguanine, cyclophosphamide, gemtuzumab ozogamicin, midostaurin, ivosidenib, enasidenib, gilteritinib, glasdegib, quizartinib, olutasidenib, vincristine, or a combination thereof. 339.The method of any one of claims 325-338, wherein the subject is human.

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