Anti-CD28 antibody and related methods

Abstract

This disclosure provides CD28-binding domains, antibodies that bind to CD28, antigen-binding antibody fragments, and multispecific antibodies. The antibodies of this disclosure include, among other things, those having desirable T-cell activation and (re)targeted target cell killing ability, and / or development potential profiles. This disclosure further provides nucleic acids and vectors encoding such antibodies or antibody fragments, and cells containing such nucleic acids. Pharmaceutical compositions, in vivo methods, and methods for producing such antibodies or antigen-binding antibody fragments are further provided.

Description

[Technical Field]

[0001] Cross-reference of related applications This application claims priority to U.S. Provisional Application No. 63 / 467,202, filed on 17 May 2023, entitled “ANTI-CD28 ANTIBODIES AND METHODS RELATED THERETO”, and U.S. Provisional Application No. 63 / 607,811, filed on 8 December 2023, entitled “ANTI-CD28 ANTIBODIES AND METHODS RELATED THERETO”. The contents of said applications are incorporated herein by reference in their entirety.

[0002] Reference to electronic sequence listings The contents of the electronic sequence listing (1160430_004413_SL.xml, size: 13,964,535 bytes, and creation date: April 23, 2024) are incorporated herein by reference in their entirety. [Background technology]

[0003] T cell activation is crucial for stimulating the immune response. T cells exhibit immunological specificity and direct most of the cellular immune response. While T cells do not secrete antibodies themselves, they are necessary for antibody secretion by B lymphocytes. T cell activation requires the involvement of numerous cell surface molecules, including the T cell receptor (TCR) complex (a disulfide-linked heterodimer, which is a membrane glycoprotein having alpha and beta (α and β) chains or gamma and delta (γ and δ) chains non-covalently linked to an immutable protein complex designated as CD3), CD4 or CD8 molecules, and receptors for costimulatory molecules (e.g., CD28 as a receptor for CD80 and CD86).

[0004] Due to its role in T cell activation, CD28 is an important therapeutic target. Based on this, agonist anti-CD28 antibodies have been studied and clinically tested as therapeutic agents for the treatment of diseases where immune activation is desirable, such as cancer (e.g., celalizumab, a super-agonist anti-CD28 monoclonal antibody (also known as TGN1412)). Agonist anti-CD28 antibodies are also thought to potentially be useful in treating autoimmune and inflammatory diseases, possibly through regulatory T cell activation (e.g., Beyersdorf et al., Ann Rheum Dis. 2005 Nov;64 Suppl 4(Suppl 4):iv91-5). Antagonist anti-CD28 antibodies have also been developed for potential use in the treatment of autoimmune diseases and inflammatory diseases and conditions, including those associated with transplantation (e.g., Vanhove et al., Antibodies (Basel). 2017 Dec;6(4):19., Suchard et al., J Immunol. 2013 Nov 1;191(9):4599-610.). However, the development of anti-CD28 antibodies has so far faced difficulties, such as the induction of cytokine release syndrome (CRS), and regulatory approval has not yet been achieved.

[0005] Recent developments and uses of multispecific antibodies, such as bispecific antibodies (bsAbs), to redirect effector T cells for targeted killing of tumor cells have shown considerable promise both preclinically and clinically (see, e.g., Topp et al, 2012, Blood 120:5185-87, Bargou et al, 2008, Science 321:974-77). Many of the bispecific antibodies developed to date contain a primary binding site specific to CD3 for T cell recruitment and activation, and a secondary binding site for targeted disease-associated antigens such as CD19 (Bassan, 2012, Blood 120:5094-95). Bispecific antibodies are thought to direct CD3+ T cells into direct contact with targeted disease cells, thereby directing them to cell-mediated cytotoxicity (Bassan, 2012).

[0006] Numerous methods are known for producing bispecific antibodies. For example, bispecific antibodies can be produced by the quadroma method, which involves the fusion of two different hybridomas, each producing a monoclonal antibody that recognizes a different antigenic site (Milstein and Cuello, Nature 1983;305:537-540). Another method for producing bispecific antibodies involves chemically tethering two different monoclonal antibodies using a heterobifunctional crosslinking agent, resulting in a hybrid conjugate that binds to two different targets (Staerz, et al. Nature 1985;314:628-631, Perez, et al. Nature 1985;316:354-356). Bispecific antibodies can also be produced by reducing each of two parental monoclonal antibodies to their respective halves, which are then mixed and reoxidized to obtain a hybrid structure (Staerz and Bevan. Proc Natl Acad Sci USA 1986;83:1453-1457). An alternative approach involves chemically crosslinking two or three separately purified Fab' fragments using a suitable linker. Several bispecific antibodies targeting CD3 and CD19 are at various stages of development and / or have been approved as therapeutic agents.

[0007] A bispecific antibody construct based on scFv, known as BITE® (Bispecific T-cell Engager), is also known, employing a single polypeptide containing two antigen-binding specificities, each contributed by congeneral VH and VL cells linked in series via a flexible linker (see, for example, Nagarsen et al, 2009, Leukemia & Lymphoma 50:886-91, Amann et al, 2009, J Immunother 32:453-64, and Baeuerle and Reinhardt, 2009, Cancer Res 69:4941-44). Another type of bispecific antibody called DART® (Dual-Affinity Re-Targeting), which utilizes a disulfide-stabilized diabody design, is also known (see, e.g., Moore et al., 2011, Blood 117:4542-51, Veri et al., 2010, Arthritis Rheum 62:1933-43). Both BITE® and DART® exhibit rapid blood clearance due to their small size (approximately 55 kDa), which necessitates frequent administration to maintain therapeutic levels of bispecific antibodies.

[0008] Furthermore, SCORPION Therapeutics (Emergent Biosolutions, Inc., Seattle, Wash.) has reported developing a platform technology that combines two antigen-binding domains in a single-strand protein, with one binding domain located at the C-terminus and a second binding domain located at the N-terminus of an effector domain base on the immunoglobulin Fc region.

[0009] A tetravalent and bispecific antibody-like protein called DVD-Ig is also known, and these are engineered from two monoclonal antibodies (Wu, C. et al., Nature Biotechnology, 25, pp. 1290-1297, 2007). To construct the DVD-Ig molecule, the V domains of two mAbs are fused in series with the variable domain of the first antibody light (VL) chain at the N-terminus, followed by the other antibody VL and Ck, by a short peptide linker (TVAAP) (SEQ ID NO: 56) to form the DVD-Ig protein light chain. The variable regions of the heavy (VH) chains of the two mAbs are fused in series with the first antibody at the N-terminus, followed by the other antibody and the heavy chain constant domain, by a short peptide linker (ASTKGP) (SEQ ID NO: 57) to form the DVD-Ig protein heavy chain (VH1 / VL1). All light and heavy chain constant domains are retained in the DVD-Ig design, and simultaneous transfection of mammalian cells with expression vectors encoding the DVD-Ig light and heavy chains has been reported to result in the secretion of a single species of IgG-like molecule with a molecular weight of approximately 200 kDa from each mAb, containing two and four binding sites.

[0010] While many candidate clinical and therapeutic bispecific antibodies have been disclosed and reported to exhibit excellent selectivity and high efficacy against the target of interest, the majority of these antibodies have been found to suffer from undesirable characteristics during downstream development and clinical efficacy studies, including binding disorder, polyspecific binding (also referred to herein and throughout), off-target binding; nonspecific binding; insufficient expression levels or profiles in mammalian host cells and eukaryotic host cells such as yeast cells; insufficient chemical and physical properties such as insufficient stability during storage (e.g., insufficient / low "shelf life"), insufficient (low) solubility, insufficient (high) viscosity, and tendency to aggregate; as well as insufficient clinical and biophysical profiles such as insufficient pharmacokinetic profiles, insufficient pharmacodynamic profiles, fast or insufficient in vivo clearance rates, and short circulating half-lives, thereby necessitating the termination of further therapeutic development of such candidate antibodies. Furthermore, antibodies derived from display technology have been observed to exhibit a tendency, at least in part by many, to be historically a minority of all clinical and commercially available antibodies, characterized by binding disorder, inadequate PK profiles, and inadequate CMC features (further assumed to be primarily due to the lack of suitable means and methods for detecting and / or counter-selecting undevelopable antibodies when screening antibodies using display technology) (see, for example, Meninger 2012, available in the hypertext transfer protocol:proteins-congress.com / wordpress / wp-content / uploads / 2012 / 01 / Trends-in-Therapeutic-Monoclonal-Antibody-Discovery-Technology.pdf).

[0011] To address these issues, certain techniques and assays have been developed to evaluate many of the aforementioned development potential features of antibodies discovered in the context of downstream development activities (post-discovery antibodies), such as CIC, SIC, BVP-ELISA, TMA, and other assays. However, such assays are typically not suitable for integration into high-throughput early polypeptide and antibody discovery platforms, such as antibody display platforms. Furthermore, evaluating these features typically requires milligram to gram quantities of protein, which limits the number of reads that can be considered commercially viable for development, and consequently reduces the likelihood of program success. As a result, vast resources are often wasted in attempts to identify lead candidates with poor characteristics, leaving little backup available in later stages of development.

[0012] Recognizing this obstacle, considerable effort has been made to develop assays with lower material requirements and to bring feasibility assessment further up the development process (Esfandiary et al., 2013, Protein Eng Des Sel 26(10):663-670, 2013; Sathish et al., 2013, Nat Rev Drug Discov. 12(4):306-24). Many of these assays aim to predict the antibody solubility and aggregation behavior of identified lead candidates. Self-interaction chromatography (SIC) and cross-interaction chromatography (CIC) are column-based low-to-medium throughput assays that correlate with and thus predict antibody solubility at relatively low concentrations (Ahamed et al., 2005, J Biol Chem 280(37):32090-100, Jacobs et al., Pharm Res 27:65-71, 2010, Spencer et al., mAbs 4(3)319-325, 2012). In addition, Sule and collaborators reported a medium-throughput gold nanoparticle assay for predicting solubility at very low concentrations, further expanding the assay range to accommodate complex cell culture media (Sule et al., Biophys J 101(7):1749-1757, 2011, Mol Pharmaceutics 10(4):1322-1331, 2013).

[0013] Furthermore, due to issues associated with multispecificity and its inadequate antibody pharmacokinetics (see Wu et al., J Mol Biol 368:652-665, 2007; Hotzel et al., 2012, mAbs 4(6):753-760), multispecific assays have been developed. For example, Wardemann and collaborators have reported an enzyme-linked immunosorbent assay (ELISA) method using LPS, insulin, dsDNA, and ssDNA to study the multireactivity of the innate antibody repertoire throughout the process of B cell maturation (Wardemann et al., 2003, Science 301(5638):1374-7). Protein biochips, in which a diverse set of proteins is placed on an array for high-throughput ELISA, are another type of screening tool. Chips containing approximately 400 different human proteins derived from Protagen (Dortmund, Germany) have been reported to be comparable to IHC staining analysis (Lueking et al., 2008, Bio Techniques 45(4):Pi-Pv) and measures of off-target binding of clinically approved TNF-alpha inhibitors (Feyen et al., Anal Bioanal Chem 391:1713-1720, 2008). Furthermore, Frese et al. reported a 384-well assay called protein panel profiling or 3P, which measures multireactivity to 32 test proteins (Frese et al., 2013, mAbs 5:2, 279-287). Using this assay, the authors demonstrated that FDA-approved therapeutic antibodies exhibit highly specific profiles to 32 test proteins and that this can be used to screen candidates from phage selection processes. Furthermore, Hotzel et al. (2012 mAbs 4(6):753-760) developed a baculovirus particle (BVP) ELISA that has been reported to predict faster antibody-nontargeted clearance in vivo.Furthermore, reagents, methods, and means for evaluating, predicting, selecting, and enriching developable therapeutic antibodies, and ultimately for generating and obtaining developable antibodies from, for example, antibody libraries, have been reported (see, for example, WO2014 / 179363).

[0014] For example, proliferative disorders such as cancer are characterized by the unregulated growth of cell subgroups. They are the leading cause of death in developed countries and the second leading cause of death in developing countries, with over 12 million new cancer cases diagnosed and 7 million cancer deaths each year. The National Cancer Institute estimates that more than 500,000 Americans died from cancer in 2013, accounting for nearly one in four deaths in the country. As the elderly population grows, the incidence of cancer also increases, as the probability of developing cancer more than doubles after the age of 70. Therefore, cancer treatment is a serious and ever-increasing social burden. Accordingly, there is a need to provide CD28-binding domains and antibodies (including multispecific antibodies) that are safe and effective, exhibiting the desired development potential and / or CRS risk profile in, for example, specifically binding to CD28 expressed on T cells, activating T cells, and (re)directing activated T cells to kill target cells. This disclosure addresses these needs. [Overview of the project]

[0015] This disclosure relates to anti-CD28 antibodies and antigen-binding antibody fragments, nucleic acids and vectors encoding such antibodies or antibody fragments, cells containing such nucleic acids, pharmaceutical compositions in therapeutic methods, and related manufacturing methods.

[0016] In one embodiment, the present disclosure provides an anti-CD28 antibody and an antigen-binding antibody fragment. An anti-CD28 antibody or antigen-binding antibody fragment according to the present disclosure may include a first heavy chain variable domain (VH-1) comprising a first heavy chain complementarity-determining region (CDR) 1 (CDRH1-1), a first heavy chain CDR2 (CDRH2-1), and a first heavy chain CDR3 (CDRH3-1), and / or a first light chain variable domain (VL-1) comprising a first light chain CDR1 (CDRL1-1), a first light chain CDR2 (CDRL2-1), and a first light chain CDR3 (CDRL3-1).

[0017] In some embodiments, the anti-CD28 antibody or antigen-binding antibody fragment may include a CDR amino acid sequence according to any one of those listed in Table 1B and / or 12B, or a variant thereof having at least about 50%, 60%, 70%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity.

[0018] In some embodiments, (a) the amino acid sequence of CDRH1-1 may include, or consist of, one of the heavy chain complementarity determination region 1 (CDRH1) amino acid sequences included in any one of the heavy chain variable domain (VH) amino acid sequences listed in Table 1A and / or 12A, and / or one of the CDRH1 amino acid sequences listed in Table 1B and / or 12B, and (b) the amino acid sequence of CDRH2-1 may include one of the heavy chain complementarity determination region included in any one of the VH amino acid sequences listed in Table 1A and / or 12A 2(CDRH2) amino acid sequence and / or one of the CDRH2 amino acid sequences listed in Table 1B and / or 12B may be included or consist of them, and / or (c)CDRH3-1 amino acid sequence may include or consist of one of the heavy chain complementarity determining region 3(CDRH3) amino acid sequences included in one of the VH amino acid sequences listed in Table 1A and / or 12A, and / or one of the CDRH3 amino acid sequences listed in Table 1B and / or 12B.

[0019] In some embodiments, (d) the amino acid sequence of CDRL1-1 may include, or consist of, one of the light chain complementarity determining region 1 (CDRL1) amino acid sequences included in any one of the light chain variable domain (VL) amino acid sequences listed in Table 1A and / or 12A, and / or one of the CDRL1 amino acid sequences listed in Table 1B and / or 12B, and (e) the amino acid sequence of CDRL2-1 may include one of the light chain phase sequences included in any one of the VL amino acid sequences listed in Table 1A and / or 12A. The complementarity-determining region 2 (CDRL2) may include, or consist of, any one of the CDRL2 amino acid sequences listed in Table 1B and / or 12B, and / or the amino acid sequence of (f)CDRL3-1 may include, or consist of, any one of the light chain complementarity-determining region 3 (CDRL3) contained in any one of the VL amino acid sequences listed in Table 1A and / or 12A, and / or the CDRL3 amino acid sequences listed in Table 1B and / or 12B.

[0020] In some embodiments, the anti-CD28 antibody or antigen-binding antibody fragment according to this disclosure is: (a) a set of heavy chain CDR amino acid sequences of a first anti-CD28 antibody selected from antibodies having amino acid sequences listed in Tables 1A-1D and / or 12A-12D; (b) a set of light chain CDR amino acid sequences of a first anti-CD28 antibody selected from antibodies having amino acid sequences listed in Tables 1A-1D and / or 12A-12D; (c) a set of amino acid sequences of the sequence listed in Tables 1A-1D and / or 12A-12D. (d) A set of heavy and light chain CDR amino acid sequences of a first anti-CD28 antibody selected from antibodies having the listed amino acid sequences, (d) a set of heavy chain CDR amino acid sequences of a first anti-CD28 antibody selected from enumerated antibodies having the amino acid sequences in Tables 1A-1D and / or 12A-12D, and a set of light chain CDR amino acid sequences of a second anti-CD28 antibody selected from antibodies having the amino acid sequences enumerated in Tables 1A-1D and / or 12A-12D. The first anti-CD28 antibody and the second anti-CD28 antibody may be the same antibody or not.

[0021] In certain embodiments, the anti-CD28 antibody or antigen-binding antibody fragment may include (A) the VH-1 and VL-1, (1) the amino acid sequences of CDRH1-1, CDRH2-1, and CDRH3-1 each include or consist of the amino acid sequences of CDRH1, CDRH2, and CDRH3 contained in the VH of the first anti-CD28 antibody, and (2) the amino acid sequences of CDRL1-1, CDRL2-1, and CDRL3-1 each include or consist of the amino acid sequences of CDRL1, CDRL2, and CDRL3 contained in the VL of the first anti-CD28 antibody. The first anti-CD28 antibody is one of the following anti-CD28 antibodies listed in Tables 1A-1D and / or 12A-12D: (i) antibody number 1, (ii) antibody number 2, (iii) antibody number 3, (iv) antibody number 4, (v) antibody number 5, (vi) antibody number 6, (vii) antibody number 7, (viii) antibody number 8, (ix) antibody number 9, (x) antibody number 10, (xi) antibody number 11, (xii) antibody number 12, (xiii) antibody number 13, (xiv) antibody number 14, (xv) antibody number 15, (xvi) antibody number 16, (xvii) antibody Number 17, (xviii) Antibody number 18, (xix) Antibody number 19, (xx) Antibody number 20, (xxi) Antibody number 21, (xxi-a) Antibody number 21a, (xxi-b) Antibody number 21b, (xxi-c) Antibody number 21c, (xxi-d) Antibody number 21d, (xxi-e) Antibody number No. 21e, (xxi-f) Antibody number 21f, (xxii) Antibody number 22, (xxiii) Antibody number 23, (xxiv) Antibody number 24, (xv) Antibody number 25, (xvi) Antibody number 26, (xvii) Antibody number 27, (xviii) Antibody number 28, (xviii-a) Antibody number 28 a, (xviii-b) Antibody number 28b, (xviii-c) Antibody number 28c, (xviii-d) Antibody number 28d, (xviii-e) Antibody number 28e, (xviii-f) Antibody number 28f, (xix) Antibody number 29, (xxx) Antibody number 30, (xxxi) Antibody number 31, ( xxxii) Antibody number 32, (xxxiii) Antibody number 33, (xxxiv) Antibody number 34, (xxxv) Antibody number 35, (xxxvi) Antibody number 36, (xxxvii) Antibody number 37, (xxxviii) Antibody number 38, (xxxix) Antibody number 39, (XL) Antibody number 40,(xli) Antibody number 41, (xlii) Antibody number 42, (xliiii) Antibody number 43, (xliv) Antibody number 44, (xlv) Antibody number 45, (xlvi) Antibody number 46, (xlvi-a) Antibody number 46 a, (xlvi-b) Antibody number 46b, (xlvi-c) Antibody number 46c, (xlvi-d) Antibody number 46d, (xlvi-e) Antibody number 46e, (xlvii) Antibody number 47, (xlviii) Antibody number No. 48, (xlix) Antibody number 49, (l) Antibody number 50, (li) Antibody number 51, (lii) Antibody number 52, (liiii) Antibody number 53, (liv) Antibody number 54, (lv) Antibody number 55, (lvi) Antibody number 56, (lvii) Antibody number 57, (lvii-a) Antibody number 57a, (lvii-b) Antibody number 57b, (lvii-c) Antibody number 57c, (lvii-d) Antibody number 57d, (lvii-e) Antibody number 57e, (lvii-f) Antibody number 57f, (lviii) Antibody number 58, (lix) Antibody number 59, (lx) Antibody number 60, (lxi) Antibody number 61, (lxi-a) Antibody number 61a, (lx i-b) Antibody number 61b, (lxi-c) Antibody number 61c, (lxi-d) Antibody number 61d, (lxi-e) Antibody number 61e, (lxii) Antibody number 62, (lxiii) Antibody number 63, (lxiv) Anti Antibody number 64, (lxv) antibody number 65, (lxvi) antibody number 66, (lxvii) antibody number 67, (lxviii) antibody number 68, (lxviii-a) antibody number 68a, (lxviii-b) antibody number 68b, (lxviii-c) antibody number 68c, (lxviii-d) antibody number 68d, (lxviii-e) antibody number 68e, (lxviii-f) antibody number 68f, or (lxix) antibody number 69.

[0022] In the specific embodiment of (A) above, the first anti-CD28 antibody may be any one of (1) antibody number 1, (2) antibody number 21, (3) antibody number 28, (4) antibody number 46, (5) antibody number 57, (6) antibody number 61, or (7) antibody number 68 according to Tables 1A to 1D. In a particular case, the first anti-CD28 antibody may be antibody number 1 according to Tables 1A to 1D.

[0023] In certain embodiments, VH-1 may be sufficient for binding to CD28, or VH-1 paired with another VL or VL-1, such as but not limited to those disclosed herein, may provide binding to CD28. Thus, in certain embodiments, the anti-CD28 antibody or antigen-binding antibody fragment may comprise (B)VH-1 and optionally VL-1, where the amino acid sequences of CDRH1-1, CDRH2-1, and CDRH3-1 comprise or consist of the amino acid sequences of CDRH1, CDRH2, and CDRH3 contained in any one of the following anti-CD28 antibodies listed in Tables 1A-1D and / or 12A-12D: (i) antibody number 1, (ii) antibody number 2, (iii) antibody Number 3, (iv) Antibody number 4, (v) Antibody number 5, (vi) Antibody number 6, (vii) Antibody number 7, (viii) Antibody number 8, (ix) Antibody number 9, (x) Antibody number 10, (xi) Antibody number 11, (xii) Antibody number 12, (xiii) Antibody number 13 , (xiv) Antibody number 14, (xv) Antibody number 15, (xvi) Antibody number 16, (xvii) Antibody number 17, (xviii) Antibody number 18, (xix) Antibody number 19, (xx) Antibody number 20, (xxi) Antibody number 21, (xxi-a) Antibody number 21 a, (xxi-b) Antibody number 21b, (xxi-c) Antibody number 21c, (xxi-d) Antibody number 21d, (xxi-e) Antibody number 21e, (xxi-f) Antibody number 21f, (xxii) Antibody number 22, (xxiii) Antibody number 23, (xxiv) Antibody body number 24, (xv) antibody number 25, (xvi) antibody number 26, (xvii) antibody number 27, (xviii) antibody number 28, (xviii-a) antibody number 28a, (xviii-b) antibody number 28b, (xviii-c) antibody number 28c, (xvi ii-d) Antibody number 28d, (xviii-e) Antibody number 28e, (xviii-f) Antibody number 28f, (xix) Antibody number 29, (xxx) Antibody number 30, (xxxi) Antibody number 31, (xxxii) Antibody number 32, (xxxiii) Antibody number 3 3, (xxxiv) Antibody number 34, (xxxv) Antibody number 35, (xxxvi) Antibody number 36, (xxxvii) Antibody number 37, (xxxviii) Antibody number 38, (xxxix) Antibody number 39, (XL) Antibody number 40, (xli) Antibody number 41,(xlii) antibody number 42, (xliii) antibody number 43, (xliv) antibody number 44, (xlv) antibody number 45, (xlvi) antibody number 46, (xlvi-a) antibody number 46a, (xlvi-b) antibody number 46b, (xlvi-c) antibody number 46c, (xlvi-d) antibody number 46d, (xlvi-e) antibody number 46e, (xlvii) antibody number 47, (xlviii) antibody number 48, (xlix) antibody number 49, (l) antibody number 50, (li) antibody number 51, (lii) antibody number 52, (liii) antibody number 53, (liv) antibody number 54, (l (v) Antibody number 55, (lvi) Antibody number 56, (lvii) Antibody number 57, (lvii-a) Antibody number 57a, (lvii-b) Antibody number 57b, (lvii-c) Antibody number 57c, (lvii-d) Antibody number 57d, (lvii-e) Antibody number 57e, (lvii-f) Antibody number 57f, (lviii) Antibody number 58, (lix) Antibody number 59, (lx) Antibody number 60, (lxi) Antibody number 61, (lxi-a) Antibody number 61a, (lxi-b) Antibody number 61b, (lxi-c) Antibody number 61c, (lxi-d) Antibody number 61d, (lxi-e) Antibody Antibody number 61e, (lxii) antibody number 62, (lxiii) antibody number 63, (lxiv) antibody number 64, (lxv) antibody number 65, (lxvi) antibody number 66, (lxvii) antibody number 67, (lxviii) antibody number 68, (lxviii-a) antibody number 68a, (lxviii-b) antibody number 68b, (lxviii-c) antibody number 68c, (lxviii-d) antibody number 68d, (lxviii-e) antibody number 68e, (lxviii-f) antibody number 68f, (lxix) antibody number 69, (lxx) antibody number 70, (lxx-a) antibody number 70 a, (lxx-b) antibody number 70b, (lxx-c) antibody number 70c, (lxx-d) antibody number 70d, (lxx-e) antibody number 70e, (lxx-f) antibody number 70f, (lxxi) antibody number 71, (lxxii) antibody number 72, (lxxiii) antibody number 73, (lxxiv) antibody number 74, (lxxv) antibody number 75, (lxxvi) antibody number 76, (lxxvii) antibody number 77, (lxxviii) antibody number 78, (lxxix) antibody number 79, (lxxx) antibody number 80, (lxxxi) antibody number 81, (lxxxii) antibody number 82.(lxxxiii) Antibody number 83, (lxxxiii-a) Antibody number 83a, (lxxxiii-b) Antibody number 83b, (lxxxiii-c) Antibody number 83c, (lxxxiii-d) Antibody number 83d, (lxxxiii-e) Antibody number 83e, (lxxxiii-f) Antibody number 83f, or (lxxxiv) Antibody number 84.

[0024] In the specific embodiment of (B) above, the anti-CD28 antibody or antigen-binding antibody fragment according to the present disclosure may comprise VH-1 and optionally VL-1, and the amino acid sequences of CDRH1-1, CDRH2-1 and CDRH3-1 comprise or consist of the amino acid sequences of CDRH1, CDRH2, and CDRH3 contained in (1) antibody number 70 or (2) antibody number 83 of VH, respectively.

[0025] In certain embodiments, the anti-CD28 antibody or antigen-binding antibody fragment may include (A) VH-1 and VL-1, where CDRH1-1, CDRH2-1, CDRH3-1, CDRL1-1, CDRL2-1, and CDRL3-1 in VH-1 and VL-1 are (i) SEQ ID NOs. 112, 114, 116, 122, 124, and 126, respectively; (ii) SEQ ID NOs. 212, 214, 216, 222, 224, and 226, respectively; (iii) SEQ ID NOs. 312, 314, 316, 322, 324, and 326, respectively; and (iv) SEQ ID NOs. 412 and 414, respectively. (v) Sequence numbers 512, 514, 516, 522, 524, and 526 respectively, (vi) Sequence numbers 612, 614, 616, 622, 624, and 626 respectively, (vii) Sequence numbers 712, 714, 716, 722, 724, and 726 respectively, (viii) Sequence numbers 812, 814, 816, 822, 824, and 826 respectively, (ix) Sequence numbers 912, 914, 916, 922, 924, and 926 respectively, (x) Sequence numbers 1012, 1014, 1016, 1022, 1024, and 1 026, (xi) Sequence numbers 1112, 1114, 1116, 1122, 1124, and 1126 respectively, (xii) Sequence numbers 1212, 1214, 1216, 1222, 1224, and 1226 respectively, (xiii) Sequence numbers 1312, 1314, 1316, 1322, 1324, and 1326 respectively, (xiv) Sequence numbers 1412, 1414, 1416, 1422, 1424, and 1426 respectively, (xv) Sequence numbers 1512, 1514, 1516, 1522, 1524, and 1526 respectively, (xvi) Sequence numbers 1612, 1614 , 1616, 1622, 1624, and 1626, (xvii) sequence numbers 1712, 1714, 1716, 1722, 1724, and 1726 respectively, (xviii) sequence numbers 1812, 1814, 1816, 1822, 1824, and 1826 respectively, (xix) sequence numbers 1912, 1914, 1916, 1922, 1924, and 1926 respectively, (xx) sequence numbers 2012, 2014, 2016, 2022, 2024, and 2026 respectively, (xxi) sequence numbers 2112, 2114, 2116, 2122, 2124, and 2126 respectively,(xxi-a) Sequence numbers 2132, 2134, 2136, 2122, 2124, and 2126 respectively, (xxi-b) Sequence numbers 2142, 2144, 2146, 2122, 2124, and 2126 respectively, (xxi-c) Sequence numbers 2152, 2154, 2156, 2122, 2124, and 2126 respectively, (xxi-d) Sequence numbers 2162, 2164, 2166, 2122, 2124, and 2126 respectively, (xxi-e) Sequence numbers 2172, 2174, 2176, 2122, 2124, and 2126 respectively, (xxi-f) Sequence number Sequence numbers 2182, 2184, 2186, 2122, 2124, and 2126, (xxii) Sequence numbers 2212, 2214, 2216, 2222, 2224, and 2226 respectively, (xxiii) Sequence numbers 2312, 2314, 2316, 2322, 2324, and 2326 respectively, (xxiv) Sequence numbers 2412, 2414, 2416, 2422, 2424, and 2426 respectively, (xxv) Sequence numbers 2512, 2514, 2516, 2522, 2524, and 2526 respectively, (xxvi) Sequence numbers 2612, 2614, 2616, and 2622 respectively , 2624, and 2626, (xxvii) sequence numbers 2712, 2714, 2716, 2722, 2724, and 2726 respectively, (xxviii) sequence numbers 2812, 2814, 2816, 2822, 2824, and 2826 respectively, (xxviii-a) sequence numbers 2832, 2834, 2836, 2822, 2824, and 2826 respectively, (xxviii-b) sequence numbers 2842, 2844, 2846, 2822, 2824, and 2826 respectively, (xxviii-c) sequence numbers 2852, 2854, 2856, 2822, 282 4, and 2826, (xxviii-d) sequence numbers 2862, 2864, 2866, 2822, 2824, and 2826 respectively, (xxviii-e) sequence numbers 2872, 2874, 2876, 2822, 2824, and 2826 respectively, (xxviii-f) sequence numbers 2882, 2884, 2886, 2822, 2824, and 2826 respectively, (xxix) sequence numbers 2912, 2914, 2916, 2922, 2924, and 2926 respectively, (xxx) sequence numbers 3012, 3014, 3016, 3022, 3024, and 3026 respectively,(xxxi) Sequence numbers 3112, 3114, 3116, 3122, 3124, and 3126 respectively, (xxxii) Sequence numbers 3212, 3214, 3216, 3222, 3224, and 3226 respectively, (xxxiii) Sequence numbers 3312, 3314, 3316, 3322, 3324, and 3326 respectively, (xxxiv) Sequence numbers 3412, 3414, 3416, 3422, 3424, and 3426 respectively, (xxxv) Sequence numbers 3512, 3514, 3516, 3522, 3524, and 3526 respectively, (xxxvi) Each Column numbers 3612, 3614, 3616, 3622, 3624, and 3626, (xxxvii) sequence numbers 3712, 3714, 3716, 3722, 3724, and 3726 respectively, (xxxviii) sequence numbers 3812, 3814, 3816, 3822, 3824, and 3826 respectively, (xxxix) sequence numbers 3912, 3914, 3916, 3922, 3924, and 3926 respectively, (xl) sequence numbers 4012, 4014, 4016, 4022, 4024, and 4026 respectively, (xli) sequence numbers 4112, 4114 respectively, 4116, 4122, 4124, and 4126, (xlii) array keys 4212, 4214, 4216, 4222, 4224, and 4226 respectively, (xliii) array keys 4312, 4314, 4316, 4322, 4324, and 4326 respectively, (xliv) array keys 4412, 4414, 4416, 4422, 4424, and 4426 respectively, (xlv) array keys 4512, 4514, 4516, 4522, 4524, and 4526 respectively, (xlvi) array keys 4612, 4614, 4616, 4622, 4624, and 4626, (xlvi-a) sequence numbers 4632, 4634, 4636, 4622, 4624, and 4626 respectively, (xlvi-b) sequence numbers 4642, 4644, 4646, 4622, 4624, and 4626 respectively, (xlvi-c) sequence numbers 4652, 4654, 4656, 4622, 4624, and 4626 respectively, (xlvi-d) sequence numbers 4662, 4664, 4666, 4622, 4624, and 4626 respectively, (xlvi-e) sequence numbers 4672, 4674, 4676, 4622, 4624, and 4626 respectively,(xlvii) Sequence numbers 4712, 4714, 4716, 4722, 4724, and 4726 respectively, (xlviii) Sequence numbers 4812, 4814, 4816, 4822, 4824, and 4826 respectively, (xlix) Sequence numbers 4912, 4914, 4916, 4922, 4924, and 4926 respectively, (l) Sequence numbers 5012, 5014, 5016, 5022, 5024, and 5026 respectively, (li) Sequence numbers 5112, 5114, 5116, 5122, 5124, and 5126 respectively, (lii) Sequence numbers 5212, 521 4, 5216, 5222, 5224, and 5226, (liii) respective sequence numbers 5312, 5314, 5316, 5322, 5324, and 5326, (liv) respective sequence numbers 5412, 5414, 5416, 5422, 5424, and 5426, (lv) respective sequence numbers 5512, 5514, 5516, 5522, 5524, and 5526, (lvi) respective sequence numbers 5612, 5614, 5616, 5622, 5624, and 5626, (lvii) respective sequence numbers 5712, 5714, 5716, 5722, 5724, and 5726, (lvii-a) Sequence numbers 5732, 5734, 5736, 5722, 5724, and 5726 respectively, (lvii-b) Sequence numbers 5742, 5744, 5746, 5722, 5724, and 5726 respectively, (lvii-c) Sequence numbers 5752, 5754, 5756, 5722, 5724, and 5726 respectively, (lvii-d) Sequence numbers 5762, 5764, 5766, 5722, 5724, and 5726 respectively, (lvii-e) Sequence numbers 5772, 5774, 5776, 5722, 5724, and 5726 respectively, (lvii-f) These are sequence numbers 5782, 5784, 5786, 5722, 5724, and 5726 respectively, (lviii) sequence numbers 5812, 5814, 5816, 5822, 5824, and 5826 respectively, (lix) sequence numbers 5912, 5914, 5916, 5922, 5924, and 5926 respectively, (lx) sequence numbers 6012, 6014, 6016, 6022, 6024, and 6026 respectively, (lxi) sequence numbers 6112, 6114, 6116, 6122, 6124, and 6126 respectively, (lxi-a) sequence numbers 6132, 6134, 6136 respectively,6122, 6124, and 6126, (lxi-b) sequence numbers 6142, 6144, 6146, 6122, 6124, and 6126 respectively, (lxi-c) sequence numbers 6152, 6154, 6156, 6122, 6124, and 6126 respectively, (lxi-d) sequence numbers 6162, 6164, 6166, 6122, 6124, and 6126 respectively, (lxi-e) sequence numbers 6172, 6174, 6176, 6122, 6124, and 6126 respectively, (lxii) sequence number 6212 , 6214, 6216, 6222, 6224, and 6226, (lxiii) respective sequence numbers 6312, 6314, 6316, 6322, 6324, and 6326, (lxiv) respective sequence numbers 6412, 6414, 6416, 6422, 6424, and 6426, (lxv) respective sequence numbers 6512, 6514, 6516, 6522, 6524, and 6526, (lxvi) respective sequence numbers 6612, 6614, 6616, 6622, 6624, and 6626, (lxvii) respective Sequence numbers 6712, 6714, 6716, 6722, 6724, and 6726, (lxviii) sequences 6812, 6814, 6816, 6822, 6824, and 6826 respectively, (lxviii-a) sequences 6832, 6834, 6836, 6822, 6824, and 6826 respectively, (lxviii-b) sequences 6842, 6844, 6846, 6822, 6824, and 6826 respectively, (lxviii-c) sequences 6852, 6854, 6856, 6822, 6 Includes or consists of 824 and 6826, (lxviii-d) sequence numbers 6862, 6864, 6866, 6822, 6824, and 6826 respectively, (lxviii-e) sequence numbers 6872, 6874, 6876, 6822, 6824, and 6826 respectively, (lxviii-f) sequence numbers 6882, 6884, 6886, 6822, 6824, and 6826 respectively, or (lxix) sequence numbers 6912, 6914, 6916, 6922, 6924, and 6926 respectively.

[0026] In a particular embodiment of (A) above, the anti-CD28 antibody or antigen-binding antibody fragment may include VH-1 and VL-1, the amino acid sequences of CDRH1-1, CDRH2-1, CDRH3-1, CDRL1-1, CDRL2-1, and CDRL3-1 in VH-1 and VL-1 include or consist of (1) SEQ ID NOs: 112, 114, 116, 122, 124, and 126, respectively.

[0027] In a particular embodiment of (A) above, the anti-CD28 antibody or antigen-binding antibody fragment may include VH-1 and VL-1, where VL-1 is kappa VL. In a particular case, the amino acid sequences of CDRH1-1, CDRH2-1, CDRH3-1, CDRL1-1, CDRL2-1, and CDRL3-1 in VH-1 and VL-1 may include (2) SEQ ID NOs. 2112, 2114, 2116, 2122, 2124, and 2126, respectively, or (3) SEQ ID NOs. 2812, 2814, 2816, 2822, 2824, and 2826, respectively, or consist of these.

[0028] In the particular embodiment of (A) above, the anti-CD28 antibody or antigen-binding antibody fragment may include VH-1 and VL-1, where VL-1 is lambda VL. In particular, the amino acid sequences of CDRH1-1, CDRH2-1, CDRH3-1, CDRL1-1, CDRL2-1, and CDRL3-1 in VH-1 and VL-1 may include (4) SEQ ID NOs. 4612, 4614, 4616, 4622, 4624, and 4626, respectively, or (5) SEQ ID NOs. 5712, 5714, 5716, 5722, 5724, and 5726, respectively, or consist of these.

[0029] In certain embodiments of (A) above, the anti-CD28 antibody or antigen-binding antibody fragment may include VH-1 and VL-1, where VL-1 can also pair with VH having specificity for CD3. In certain cases, the amino acid sequences of CDRH1-1, CDRH2-1, CDRH3-1, CDRL1-1, CDRL2-1, and CDRL3-1 in the VH-1 and VL-1 may include (6) SEQ ID NOs. 6112, 6114, 6116, 6122, 6124, and 6126, respectively, or (7) SEQ ID NOs. 6812, 6814, 6816, 6822, 6824, and 6826, respectively, or consist of these.

[0030] In certain embodiments, VH-1 may be sufficient for binding to CD28, or VH-1 paired with another VL or VL-1, such as but not limited to those disclosed herein, may provide binding to CD28. Thus, in certain embodiments, the anti-CD28 antibody or antigen-binding antibody fragment may comprise (B) the VH-1 and optionally the VL-1, where the amino acid sequences of CDRH1-1, CDRH2-1, and CDRH3-1 in the VH-1 are (i) SEQ ID NOs. 112, 114, and 116, respectively; (ii) SEQ ID NOs. 212, 214, and 216, respectively; (iii) SEQ ID NOs. 312, 314, and 316, respectively; (iv) SEQ ID NOs. 412, 414, and 416, respectively; and (v) SEQ ID NOs. (vi) Sequence numbers 512, 514, and 516 respectively, (vii) Sequence numbers 712, 714, and 716 respectively, (viii) Sequence numbers 812, 814, and 816 respectively, (ix) Sequence numbers 912, 914, and 916 respectively, (x) Sequence numbers 1012, 1014, and 1016 respectively, (xi) Sequence numbers 1112, 1114, and 1116 respectively, (xii) Sequence numbers 1212, 1214, and 1216 respectively, (xiii) Sequence number 1 312, 1314, and 1316, (xiv) sequence numbers 1412, 1414, and 1416 respectively, (xv) sequence numbers 1512, 1514, and 1516 respectively, (xvi) sequence numbers 1612, 1614, and 1616 respectively, (xvii) sequence numbers 1712, 1714, and 1716 respectively, (xviii) sequence numbers 1812, 1814, and 1816 respectively, (xix) sequence numbers 1912, 1914, and 1916 respectively, (xx) sequence numbers 2012, 2014, and 20 16, (xxi) Sequence numbers 2112, 2114, and 2116 respectively, (xxi-a) Sequence numbers 2132, 2134, and 2136 respectively, (xxi-b) Sequence numbers 2142, 2144, and 2146 respectively, (xxi-c) Sequence numbers 2152, 2154, and 2156 respectively, (xxi-d) Sequence numbers 2162, 2164, and 2166 respectively, (xxi-e) Sequence numbers 2172, 2174, and 2176 respectively, (xxi-f) Sequence numbers 2182, 2184, and 2186 respectively,(xxii) Sequence numbers 2212, 2214, and 2216 respectively, (xxiii) Sequence numbers 2312, 2314, and 2316 respectively, (xxiv) Sequence numbers 2412, 2414, and 2416 respectively, (xxv) Sequence numbers 2512, 2514, and 2516 respectively, (xxvi) Sequence numbers 2612, 2614, and 2616 respectively, (xxvii) Sequence numbers 2712, 2714, and 2716 respectively, (xxviii) Sequence numbers 2812, 2814, and 2816 respectively, (xxviii-a) Sequence numbers 2832, 2834 respectively, and 2836, (xxviii-b) sequence numbers 2842, 2844, and 2846 respectively, (xxviii-c) sequence numbers 2852, 2854, and 2856 respectively, (xxviii-d) sequence numbers 2862, 2864, and 2866 respectively, (xxviii-e) sequence numbers 2872, 2874, and 2876 respectively, (xxviii-f) sequence numbers 2882, 2884, and 2886 respectively, (xxix) sequence numbers 2912, 2914, and 2916 respectively, (xxx) sequence numbers 3012, 3014, and 3016 respectively, (xxxi) (xxxii) Sequence numbers 3112, 3114, and 3116 respectively, (xxxii) Sequence numbers 3212, 3214, and 3216 respectively, (xxxiii) Sequence numbers 3312, 3314, and 3316 respectively, (xxxiv) Sequence numbers 3412, 3414, and 3416 respectively, (xxxv) Sequence numbers 3512, 3514, and 3516 respectively, (xxxvi) Sequence numbers 3612, 3614, and 3616 respectively, (xxxvii) Sequence numbers 3712, 3714, and 3716 respectively, (xxxviii) Sequence numbers 3812, 3814, and 38 16, (xxxix) sequence numbers 3912, 3914, and 3916 respectively, (xl) sequence numbers 4012, 4014, and 4016 respectively, (xli) sequence numbers 4112, 4114, and 4116 respectively, (xlii) sequence numbers 4212, 4214, and 4216 respectively, (xliii) sequence numbers 4312, 4314, and 4316 respectively, (xliv) sequence numbers 4412, 4414, and 4416 respectively, (xlv) sequence numbers 4512, 4514, and 4516 respectively, (xlvi) sequence numbers 4612, 4614, and 4616 respectively,(xlvi-a) Sequence numbers 4632, 4634, and 4636 respectively, (xlvi-b) Sequence numbers 4642, 4644, and 4646 respectively, (xlvi-c) Sequence numbers 4652, 4654, and 4656 respectively, (xlvi-d) Sequence numbers 4662, 4664, and 4666 respectively, (xlvi-e) Sequence numbers 4672, 4674, and 4676 respectively, (xlvii) Sequence numbers 4712, 4714, and 4716 respectively, (xlviii) Sequence numbers 4812, 4814, and 4816 respectively, (xlix) Sequence number 4912 respectively, 4914 and 4916, (l) SEQ ID NOs 5012, 5014, and 5016 respectively, (li) SEQ ID NOs 5112, 5114, and 5116 respectively, (lii) SEQ ID NOs 5212, 5214, and 5216 respectively, (liii) SEQ ID NOs 5312, 5314, and 5316 respectively, (liv) SEQ ID NOs 5412, 5414, and 5416 respectively, (lv) SEQ ID NOs 5512, 5514, and 5516 respectively, (lvi) SEQ ID NOs 5612, 5614, and 5616 respectively, (lvii) SEQ ID NOs 5712, 5714, and 5716 respectively , (lvii-a) Sequence numbers 5732, 5734, and 5736 respectively, (lvii-b) Sequence numbers 5742, 5744, and 5746 respectively, (lvii-c) Sequence numbers 5752, 5754, and 5756 respectively, (lvii-d) Sequence numbers 5762, 5764, and 5766 respectively, (lvii-e) Sequence numbers 5772, 5774, and 5776 respectively, (lvii-f) Sequence numbers 5782, 5784, and 5786 respectively, (lviii) Sequence numbers 5812, 5814, and 5816 respectively, (lix) Sequence number 5912 respectively, 5914 and 5916, (lx) sequence numbers 6012, 6014, and 6016 respectively, (lxi) sequence numbers 6112, 6114, and 6116 respectively, (lxi-a) sequence numbers 6132, 6134, and 6136 respectively, (lxi-b) sequence numbers 6142, 6144, and 6146 respectively, (lxi-c) sequence numbers 6152, 6154, and 6156 respectively, (lxi-d) sequence numbers 6162, 6164, and 6166 respectively, (lxi-e) sequence numbers 6172, 6174, and 6176 respectively, (lxii) sequence number 6212 respectively,6214 and 6216, (lxiii) sequence numbers 6312, 6314, and 6316 respectively, (lxiv) sequence numbers 6412, 6414, and 6416 respectively, (lxv) sequence numbers 6512, 6514, and 6516 respectively, (lxvi) sequence numbers 6612, 6614, and 6616 respectively, (lxvii) sequence numbers 6712, 6714, and 6716 respectively, (lxviii) sequence numbers 6812, 6814, and 6816 respectively, (lxviii-a) sequence numbers 6832, 6834, and 6836 respectively, (lxviii-b) These are sequence numbers 6842, 6844, and 6846 respectively, (lxviii-c) sequence numbers 6852, 6854, and 6856 respectively, (lxviii-d) sequence numbers 6862, 6864, and 6866 respectively, (lxviii-e) sequence numbers 6872, 6874, and 6876 respectively, (lxviii-f) sequence numbers 6882, 6884, and 6886 respectively, (lxix) sequence numbers 6912, 6914, and 6916 respectively, (lxx) sequence numbers 7012, 7014, and 7016 respectively, (lxx-a) sequence number 7032 respectively, 7034 and 7036, (lxx-b) sequence numbers 7042, 7044, and 7046 respectively, (lxx-c) sequence numbers 7052, 7054, and 7056 respectively, (lxx-d) sequence numbers 7062, 7064, and 7066 respectively, (lxx-e) sequence numbers 7072, 7074, and 7076 respectively, (lxx-f) sequence numbers 7082, 7084, and 7086 respectively, (lxxxi) sequence numbers 7112, 7114, and 7116 respectively, (lxxii) sequence numbers 7212, 7214, and 7216 respectively, (lxxiii) each (lxxiv) Sequence numbers 7312, 7314, and 7316 respectively, (lxxv) Sequence numbers 7412, 7414, and 7416 respectively, (lxxv) Sequence numbers 7512, 7514, and 7516 respectively, (lxxvi) Sequence numbers 7612, 7614, and 7616 respectively, (lxxvii) Sequence numbers 7712, 7714, and 7716 respectively, (lxxviii) Sequence numbers 7812, 7814, and 7816 respectively, (lxxix) Sequence numbers 7912, 7914, and 7916 respectively, (lxxx) Sequence numbers 8012, 8014, and 8016 respectively,(lxxxi) Sequence numbers 8112, 8114, and 8116 respectively, (lxxxii) Sequence numbers 8212, 8214, and 8216 respectively, (lxxxiii) Sequence numbers 8312, 8314, and 8316 respectively, (lxxxiii-a) Sequence numbers 8332, 8334, and 8336 respectively, (lxxxiii-b) Sequence numbers 8342, 8344, and 8346 respectively, (lxxxiii-c) Each of these includes or consists of sequence numbers 8352, 8354, and 8356, (lxxxiii-d) each of sequence numbers 8362, 8364, and 8366, (lxxxiii-e) each of sequence numbers 8372, 8374, and 8376, (lxxxiii-f) each of sequence numbers 8382, 8384, and 8386, or (lxxxiv) each of sequence numbers 8412, 8414, and 8416.

[0031] In the specific embodiment of (B) above, for example, if VH-1 is sufficient to bind to CD28, or if VH-1 paired with another VL or VL-1, such as but not limited to those disclosed herein, can provide binding to CD28, the anti-CD28 antibody or antigen-binding antibody fragment may comprise VH-1 and optionally VL-1, wherein the amino acid sequences of CDRH1-1, CDRH2-1, and CDRH3-1 in the VH-1 comprise (1) SEQ ID NOs. 7012, 7014, and 7016, respectively, or (2) SEQ ID NOs. 8312, 8314, and 8316, respectively.

[0032] In certain embodiments, the amino acid sequence of VH-1 may include, or consist of, one of the VH amino acid sequences listed in Table 1A and / or 12A, or variants thereof having at least about 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity thereto.

[0033] In certain embodiments, the amino acid sequence of VL-1 may include, or consist of, one of the VL amino acid sequences listed in Table 1A and / or 12A, or variants thereof having at least about 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity thereto.

[0034] In certain embodiments, the amino acid sequence of VH-1 may be encoded by a nucleic acid sequence comprising, or consisting of, one of the VH-coding nucleic acid sequences listed in Table 2A and / or 13A, or a variant thereof having at least about 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity thereto.

[0035] In certain embodiments, the amino acid sequence of VL-1 may be encoded by any one of the VL-coding nucleic acid sequences listed in Table 2A and / or 13A, or by a variant thereof having at least about 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity, or by a nucleic acid sequence comprising such a variant.

[0036] In a particular embodiment, in (A) above, the amino acid sequences of VH-1 and VL-1 are: (i) SEQ ID NOs. 110 and 120, respectively; (ii) SEQ ID NOs. 210 and 220, respectively; (iii) SEQ ID NOs. 310 and 320, respectively; (iv) SEQ ID NOs. 410 and 420, respectively; (v) SEQ ID NOs. 510 and 520, respectively; (vi) SEQ ID NOs. 610 and 620, respectively; (vii) SEQ ID NOs. 710 and 720, respectively; (viii) SEQ ID NOs. 810 and 820, respectively; (ix (x) has sequence numbers 910 and 920 respectively, (x) has sequence numbers 1010 and 1020 respectively, (xi) has sequence numbers 1110 and 1120 respectively, (xii) has sequence numbers 1210 and 1220 respectively, (xiii) has sequence numbers 1310 and 1320 respectively, (xiv) has sequence numbers 1410 and 1420 respectively, (xv) has sequence numbers 1510 and 1520 respectively, (xvi) has sequence numbers 1610 and 1620 respectively, (xvii) has sequence numbers 1710 and 1720 respectively, (xvi ii) Sequence numbers 1810 and 1820 respectively, (xix) sequence numbers 1910 and 1920 respectively, (xx) sequence numbers 2010 and 2020 respectively, (xxi) sequence numbers 2110 and 2120 respectively, (xxi-a) sequence numbers 2130 and 2120 respectively, (xxi-b) sequence numbers 2140 and 2120 respectively, (xxi-c) sequence numbers 2150 and 2120 respectively, (xxi-d) sequence numbers 2160 and 2120 respectively, (xxi-e) sequence numbers Sequence numbers 2170 and 2120, sequence numbers 2180 and 2120 in (xxi-f) respectively, sequence numbers 2210 and 2220 in (xxii) respectively, sequence numbers 2310 and 2320 in (xxiii) respectively, sequence numbers 2410 and 2420 in (xxiv) respectively, sequence numbers 2510 and 2520 in (xxv) respectively, sequence numbers 2610 and 2620 in (xxvi) respectively, sequence numbers 2710 and 2720 in (xxvii) respectively, sequence numbers 2810 and 2820 in (xxviii) respectively,Sequence numbers 2830 and 2820 in (xxviii-a), 2840 and 2820 in (xxviii-b), 2850 and 2820 in (xxviii-c), 2860 and 2820 in (xxviii-d), 2870 and 2820 in (xxviii-e), 2880 and 2820 in (xxviii-f), 2910 and 2920 in (xxix), and 3010 in (xxx). bi 3020, (xxxi) sequence numbers 3110 and 3120 respectively, (xxxii) sequence numbers 3210 and 3220 respectively, (xxxiii) sequence numbers 3310 and 3320 respectively, (xxxiv) sequence numbers 3410 and 3420 respectively, (xxxv) sequence numbers 3510 and 3520 respectively, (xxxvi) sequence numbers 3610 and 3620 respectively, (xxxvii) sequence numbers 3710 and 3720 respectively, (xxxviii) sequence numbers 3810 and 3820 respectively, (x (xxix) Sequence IDs 3910 and 3920 respectively, (xl) Sequence IDs 4010 and 4020 respectively, (xli) Sequence IDs 4110 and 4120 respectively, (xlii) Sequence IDs 4210 and 4220 respectively, (xliii) Sequence IDs 4310 and 4320 respectively, (xliiv) Sequence IDs 4410 and 4420 respectively, (xlv) Sequence IDs 4510 and 4520 respectively, (xlvi) Sequence IDs 4610 and 4620 respectively, (xlvi-a) Sequence ID 4 630 and 4620, (xlvi-b) sequence numbers 4640 and 4620 respectively, (xlvi-c) sequence numbers 4650 and 4620 respectively, (xlvi-d) sequence numbers 4660 and 4620 respectively, (xlvi-e) sequence numbers 4670 and 4620 respectively, (xlvii) sequence numbers 4710 and 4720 respectively, (xlviii) sequence numbers 4810 and 4820 respectively, (xlix) sequence numbers 4910 and 4920 respectively, (l) sequence numbers 5010 and 5020 respectively,(li) contains sequence numbers 5110 and 5120 respectively, (lii) contains sequence numbers 5210 and 5220 respectively, (liii) contains sequence numbers 5310 and 5320 respectively, (liv) contains sequence numbers 5410 and 5420 respectively, (lv) contains sequence numbers 5510 and 5520 respectively, (lvi) contains sequence numbers 5610 and 5620 respectively, (lvii) contains sequence numbers 5710 and 5720 respectively, (lvii-a) contains sequence numbers 5730 and 5720 respectively, and (lvii-b) contains sequence numbers Sequence numbers 5740 and 5720, (lvii-c) sequence numbers 5750 and 5720 respectively, (lvii-d) sequence numbers 5760 and 5720 respectively, (lvii-e) sequence numbers 5770 and 5720 respectively, (lvii-f) sequence numbers 5780 and 5720 respectively, (lvii-f) sequence numbers 5810 and 5820 respectively, (lviii) sequence numbers 5910 and 5920 respectively, (lix) sequence numbers 6010 and 6020 respectively, (lx) sequence numbers 6110 and 61 20, SEQ ID NOs 6130 and 6120 in (lxi-a), SEQ ID NOs 6140 and 6120 in (lxi-b), SEQ ID NOs 6150 and 6120 in (lxi-c), SEQ ID NOs 6160 and 6120 in (lxi-d), SEQ ID NOs 6170 and 6120 in (lxi-e), SEQ ID NOs 6210 and 6220 in (lxii), SEQ ID NOs 6310 and 6320 in (lxiii), SEQ ID NOs 6410 and 6420 in (lxiv), (lxv) Sequence numbers 6510 and 6520 in (lxvi), sequence numbers 6610 and 6620 in (lxvii), sequence numbers 6710 and 6720 in (lxvii), sequence numbers 6830 and 6820 in (lxviii-a), sequence numbers 6840 and 6820 in (lxviii-b), sequence numbers 6850 and 6820 in (lxviii-c), sequence numbers 6860 and 6820 in (lxviii-d), and sequence numbers 6870 and 6820 in (lxviii-e).(lxviii-f) may have at least approximately 80%, at least approximately 85%, at least approximately 90%, at least approximately 91%, at least approximately 92%, at least approximately 93%, at least approximately 94%, at least approximately 95%, at least approximately 96%, at least approximately 97%, at least approximately 98%, or at least or at least approximately 99% sequence identity with respect to sequence numbers 6880 and 6820 in (lxviii), at least approximately 6810 and 6820 in (lxix), or at least approximately 6910 and 6920 in (lxix).

[0037] In a particular embodiment, in (A) above, the amino acid sequences of VH-1 and VL-1 are: (1) SEQ ID NOs. 110 and 120 respectively (i.e., including the heavy and light chain CDRs of antibody number 1 on one hand), (2) SEQ ID NOs. 2110 and 2120 respectively (i.e., including the heavy and light chain CDRs of antibody number 21 on one hand), (3) SEQ ID NOs. 2810 and 2820 respectively (i.e., including the heavy and light chain CDRs of antibody number 28 on one hand), (4) SEQ ID NOs. 4610 and 4620 respectively (i.e., including the heavy and light chain CDRs of antibody number 46 on one hand), (5) SEQ ID NOs. 5710 and 5720 respectively ( That is, it may have at least about 80%, at least about 85%, at least about 90%, at least about 91%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, or at least or at least about 99% sequence identity with respect to (6) SEQ ID NOs. 6110 and 6120 respectively (i.e., at least about 61 heavy chain and light chain CDR), or (7) SEQ ID NOs. 6810 and 6820 respectively (i.e., at least about 68 heavy chain and light chain CDR).

[0038] In a particular embodiment, in (B) above, the amino acid sequence of VH-1 is: (i) SEQ ID NO: 110, (ii) SEQ ID NO: 210, (iii) SEQ ID NO: 310, (iv) SEQ ID NO: 410, (v) SEQ ID NO: 510, (vi) SEQ ID NO: 610, (vii) SEQ ID NO: 710, (viii) SEQ ID NO: 810, (ix) SEQ ID NO: 910, (x) SEQ ID NO: 1010, (xi) SEQ ID NO: 1110, (xii) SEQ ID NO: 1210, (xiii) SEQ ID NO: 1310, SEQ ID NO: 1410 in (xiv), SEQ ID NO: 1510 in (xv), SEQ ID NO: 1610 in (xvi), SEQ ID NO: 1710 in (xvii), SEQ ID NO: 1810 in (xviii), SEQ ID NO: 1910 in (xix), SEQ ID NO: 2010 in (xx), SEQ ID NO: 2110 in (xxi), SEQ ID NO: 2130 in (xxi-a), SEQ ID NO: 2140 in (xx-b), SEQ ID NO: 2150 in (xxi-c), SEQ ID NO: 2160 in (xxi-d), SEQ ID NO: 217 in (xxi-e) 0, SEQ ID NO: 2180 in (xxi-f), SEQ ID NO: 2210 in (xxii), SEQ ID NO: 2310 in (xxiii), SEQ ID NO: 2410 in (xxiv), SEQ ID NO: 2510 in (xxv), SEQ ID NO: 2610 in (xxvi), SEQ ID NO: 2710 in (xxvii), SEQ ID NO: 2810 in (xxviii), SEQ ID NO: 2830 in (xxviii-a), SEQ ID NO: 2840 in (xxviii-b), SEQ ID NO: 2850 in (xxviii-c), SEQ ID NO: 28 in (xxviii-d) 60, SEQ ID NO: 2870 in (xxviii-e), SEQ ID NO: 2880 in (xxviii-f), SEQ ID NO: 2910 in (xxix), SEQ ID NO: 3010 in (xxx), SEQ ID NO: 3110 in (xxxi), SEQ ID NO: 3210 in (xxxii), SEQ ID NO: 3310 in (xxxiii), SEQ ID NO: 3410 in (xxxiv), SEQ ID NO: 3510 in (xxxv), SEQ ID NO: 3610 in (xxxvi), SEQ ID NO: 3710 in (xxxvii), SEQ ID NO: 3810 in (xxxviii),SEQ ID NO: 3910 in (xxxix), 4010 in (xl), 4110 in (xli), 4210 in (xlii), 4310 in (xliii), 4410 in (xliv), 4510 in (xlv), 4610 in (xlvi), 4630 in (xlvi-a), 4640 in (xlvi-b), 4650 in (xlvi-c), 4660 in (xlvi-d), in (xlvi-e) Sequence ID 4670, Sequence ID 4710 in (xlvii), Sequence ID 4810 in (xlviii), Sequence ID 4910 in (xlix), Sequence ID 5010 in (l), Sequence ID 5110 in (li), Sequence ID 5210 in (lii), Sequence ID 5310 in (liii), Sequence ID 5410 in (liv), Sequence ID 5510 in (lv), Sequence ID 5610 in (lvi), Sequence ID 5710 in (lvii), Sequence ID 5730 in (lvii-a), Sequence ID in (lvii-b) Number 5740, SEQ ID NO: 5750 in (lvii-c), SEQ ID NO: 5760 in (lvii-d), SEQ ID NO: 5770 in (lvii-e), SEQ ID NO: 5780 in (lvii-f), SEQ ID NO: 5810 in (lviii), SEQ ID NO: 5910 in (lix), SEQ ID NO: 6010 in (lx), SEQ ID NO: 6110 in (lxi), SEQ ID NO: 6130 in (lxi-a), SEQ ID NO: 6140 in (lxi-b), SEQ ID NO: 6150 in (lxi-c), SEQ ID NO: 6160 in (lxi-d), (l Sequence ID 6170 in (lxii), Sequence ID 6210 in (lxii), Sequence ID 6310 in (lxiii), Sequence ID 6410 in (lxiv), Sequence ID 6510 in (lxv), Sequence ID 6610 in (lxvi), Sequence ID 6710 in (lxvii), Sequence ID 6810 in (lxviii), Sequence ID 6830 in (lxviii-a), Sequence ID 6840 in (lxviii-b), Sequence ID 6850 in (lxviii-c), Sequence ID 6860 in (lxviii-d),SEQ ID NOs: 6870 in (lxviii-e), 6880 in (lxviii-f), 6910 in (lxix), 7010 in (lxx), 7030 in (lxx-a), 7040 in (lxx-b), 7050 in (lxx-c), 7060 in (lxx-d), 7070 in (lxx-e), 7080 in (lxx-f), 7110 in (lxxi), 7210 in (lxxii), 7310 in (lxxiii), 7410 in (lxxiv), 7510 in (lxxv), 7610 in (lxxvi), 7710 in (lxxvii), 7810 in (lxxviii), or 7910 in (lxxix), (l The sequence may have at least approximately 80%, at least approximately 85%, at least approximately 90%, at least approximately 91%, at least approximately 92%, at least approximately 93%, at least approximately 94%, at least approximately 95%, at least approximately 96%, at least approximately 97%, at least approximately 98%, or at least or at least approximately 99% sequence identity with sequence number 8010 in (xxx), sequence number 8110 in (lxxxi), sequence number 8210 in (lxxxii), sequence number 8310 in (lxxxiii-a), sequence number 8330 in (lxxxiii-b), sequence number 8340 in (lxxxiii-c), sequence number 8350 in (lxxxiii-d), sequence number 8360 in (lxxxiii-e), sequence number 8370 in (lxxxiii-f), sequence number 8380 in (lxxxiii-f), or sequence number 8410 in (lxxxiv).

[0039] In certain embodiments, in (B) above, the amino acid sequence of VH-1 may have at least about 80%, at least about 85%, at least about 90%, at least about 91%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, or at least or at least about 99% sequence identity with SEQ ID NO: 7010 in (1) (i.e., including the heavy and light chain CDR of antibody number 70 on one hand) or SEQ ID NO: 8310 in (2) (i.e., including the heavy and light chain CDR of antibody number 831 on the other hand).

[0040] In a particular embodiment, in (A) above, the amino acid sequences of VH-1 and VL-1 are as follows: (i) SEQ ID NOs. 110 and 120, respectively; (ii) SEQ ID NOs. 210 and 220, respectively; (iii) SEQ ID NOs. 310 and 320, respectively; (iv) SEQ ID NOs. 410 and 420, respectively; (v) SEQ ID NOs. 510 and 520, respectively; (vi) SEQ ID NOs. 610 and 620, respectively; (vii) SEQ ID NOs. 710 and 720, respectively; (viii) SEQ ID NOs. 810 and 820, respectively; (ix) (x) and (xii) respectively, sequence numbers 910 and 920, (x) respectively, sequence numbers 1010 and 1020, (xii) respectively, sequence numbers 1110 and 1120, (xii) respectively, sequence numbers 1210 and 1220, (xiii) respectively, sequence numbers 1310 and 1320, (xiv) respectively, sequence numbers 1410 and 1420, (xv) respectively, sequence numbers 1510 and 1520, (xvi) respectively, sequence numbers 1610 and 1620, (xvii) respectively, sequence numbers 1710 and 1720, (xvii i) Sequence numbers 1810 and 1820 respectively, (xix) sequence numbers 1910 and 1920 respectively, (xx) sequence numbers 2010 and 2020 respectively, (xxi) sequence numbers 2110 and 2120 respectively, (xxi-a) sequence numbers 2130 and 2120 respectively, (xxi-b) sequence numbers 2140 and 2120 respectively, (xxi-c) sequence numbers 2150 and 2120 respectively, (xxi-d) sequence numbers 2160 and 2120 respectively, (xxi-e) sequence numbers 2170 and 2120, sequence numbers 2180 and 2120 in (xxi-f) respectively, sequence numbers 2210 and 2220 in (xxii) respectively, sequence numbers 2310 and 2320 in (xxiii) respectively, sequence numbers 2410 and 2420 in (xxiv) respectively, sequence numbers 2510 and 2520 in (xxv) respectively, sequence numbers 2610 and 2620 in (xxvi) respectively, sequence numbers 2710 and 2720 in (xxvii) respectively, sequence numbers 2810 and 2820 in (xxviii) respectively,Sequence numbers 2830 and 2820 in (xxviii-a), 2840 and 2820 in (xxviii-b), 2850 and 2820 in (xxviii-c), 2860 and 2820 in (xxviii-d), 2870 and 2820 in (xxviii-e), 2880 and 2820 in (xxviii-f), 2910 and 2920 in (xxix), and 3010 in (xxx). bi 3020, (xxxi) sequence numbers 3110 and 3120 respectively, (xxxii) sequence numbers 3210 and 3220 respectively, (xxxiii) sequence numbers 3310 and 3320 respectively, (xxxiv) sequence numbers 3410 and 3420 respectively, (xxxv) sequence numbers 3510 and 3520 respectively, (xxxvi) sequence numbers 3610 and 3620 respectively, (xxxvii) sequence numbers 3710 and 3720 respectively, (xxxviii) sequence numbers 3810 and 3820 respectively, (x (xxix) Sequence IDs 3910 and 3920 respectively, (xl) Sequence IDs 4010 and 4020 respectively, (xli) Sequence IDs 4110 and 4120 respectively, (xlii) Sequence IDs 4210 and 4220 respectively, (xliii) Sequence IDs 4310 and 4320 respectively, (xliiv) Sequence IDs 4410 and 4420 respectively, (xlv) Sequence IDs 4510 and 4520 respectively, (xlvi) Sequence IDs 4610 and 4620 respectively, (xlvi-a) Sequence ID 4 630 and 4620, (xlvi-b) sequence numbers 4640 and 4620 respectively, (xlvi-c) sequence numbers 4650 and 4620 respectively, (xlvi-d) sequence numbers 4660 and 4620 respectively, (xlvi-e) sequence numbers 4670 and 4620 respectively, (xlvii) sequence numbers 4710 and 4720 respectively, (xlviii) sequence numbers 4810 and 4820 respectively, (xlix) sequence numbers 4910 and 4920 respectively, (l) sequence numbers 5010 and 5020 respectively,(li) contains sequence numbers 5110 and 5120 respectively, (lii) contains sequence numbers 5210 and 5220 respectively, (liii) contains sequence numbers 5310 and 5320 respectively, (liv) contains sequence numbers 5410 and 5420 respectively, (lv) contains sequence numbers 5510 and 5520 respectively, (lvi) contains sequence numbers 5610 and 5620 respectively, (lvii) contains sequence numbers 5710 and 5720 respectively, (lvii-a) contains sequence numbers 5730 and 5720 respectively, and (lvii-b) contains sequence numbers Sequence numbers 5740 and 5720, sequence numbers 5750 and 5720 in (lvii-c) respectively, sequence numbers 5760 and 5720 in (lvii-d) respectively, sequence numbers 5770 and 5720 in (lvii-e) respectively, sequence numbers 5780 and 5720 in (lvii-f) respectively, sequence numbers 5810 and 5820 in (lviii) respectively, sequence numbers 5910 and 5920 in (lix) respectively, sequence numbers 6010 and 6020 in (lx) respectively, sequence numbers 6110 and 6 in (lxi) respectively 120, (lxi-a) with sequence numbers 6130 and 6120 respectively, (lxi-b) with sequence numbers 6140 and 6120 respectively, (lxi-c) with sequence numbers 6150 and 6120 respectively, (lxi-d) with sequence numbers 6160 and 6120 respectively, (lxi-e) with sequence numbers 6170 and 6120 respectively, (lxii) with sequence numbers 6210 and 6220 respectively, (lxiii) with sequence numbers 6310 and 6320 respectively, (lxiv) with sequence numbers 6410 and 6420 respectively, (lxv Sequence numbers 6510 and 6520 in (lxvi), sequence numbers 6610 and 6620 in (lxvii), sequence numbers 6710 and 6720 in (lxvii), sequence numbers 6810 and 6820 in (lxviii), sequence numbers 6830 and 6820 in (lxviii-a), sequence numbers 6840 and 6820 in (lxviii-b), sequence numbers 6850 and 6820 in (lxviii-c), and sequence numbers 6860 and 6820 in (lxviii-d).(lxviii-e) may include, or consist of, sequence numbers 6870 and 6820, respectively, sequence numbers 6880 and 6820, respectively, in (lxviii-f), or sequence numbers 6910 and 6920, respectively, in (lxix).

[0041] In certain embodiments of (A) above, the amino acid sequences of VH-1 and VL-1 may include, or consist of, sequence numbers 110 and 120 in (1).

[0042] In certain embodiments of (A) above, in some cases VL-1 may be kappa VL. In certain cases the amino acid sequences of VH-1 and VL-1 may include or consist of SEQ ID NOs. 2110 and 2120 in (2), or SEQ ID NOs. 2810 and 2820 in (3), respectively.

[0043] In certain embodiments of (A) above, in some cases VL-1 may be lambda VL. In certain cases the amino acid sequences of VH-1 and VL-1 may include or consist of SEQ ID NOs. 4610 and 4620 in (4), or SEQ ID NOs. 5710 and 5720 in (5), respectively.

[0044] In certain embodiments of (A) above, in some cases, VL-1 can also pair with VH having specificity for CD3 (i.e., a common VL that can be shared by a CD28 binding domain and a CD3 binding domain). In certain cases, the amino acid sequences of VH-1 and VL-1 may include, or consist of, sequence numbers 6110 and 6120 in (6) or sequence numbers 6810 and 6820 in (7).

[0045] In a particular embodiment, in (B) above, the amino acid sequence of VH-1 is: (i) SEQ ID NO: 110, (ii) SEQ ID NO: 210, (iii) SEQ ID NO: 310, (iv) SEQ ID NO: 410, (v) SEQ ID NO: 510, (vi) SEQ ID NO: 610, (vii) SEQ ID NO: 710, (viii) SEQ ID NO: 810, (ix) SEQ ID NO: 910, (x) SEQ ID NO: 1010, (xi) SEQ ID NO: 1110, (xii) SEQ ID NO: 1210, (xiii) SEQ ID NO: 1 310, SEQ ID NO: 1410 in (xiv), SEQ ID NO: 1510 in (xv), SEQ ID NO: 1610 in (xvi), SEQ ID NO: 1710 in (xvii), SEQ ID NO: 1810 in (xviii), SEQ ID NO: 1910 in (xix), SEQ ID NO: 2010 in (xx), SEQ ID NO: 2110 in (xxi), SEQ ID NO: 2130 in (xxi-a), SEQ ID NO: 2140 in (xx-b), SEQ ID NO: 2150 in (xxi-c), SEQ ID NO: 2160 in (xxi-d), SEQ ID NO: 2170 in (xxi-e) , (xxi-f) SEQ ID NO: 2180, (xxii) SEQ ID NO: 2210, (xxiii) SEQ ID NO: 2310, (xxiv) SEQ ID NO: 2410, (xxv) SEQ ID NO: 2510, (xxvi) SEQ ID NO: 2610, (xxvii) SEQ ID NO: 2710, (xxviii) SEQ ID NO: 2810, (xxviii-a) SEQ ID NO: 2830, (xxviii-b) SEQ ID NO: 2840, (xxviii-c) SEQ ID NO: 2850, (xxviii-d) SEQ ID NO: 286 0, SEQ ID NO: 2870 in (xxviii-e), SEQ ID NO: 2880 in (xxviii-f), SEQ ID NO: 2910 in (xxix), SEQ ID NO: 3010 in (xxx), SEQ ID NO: 3110 in (xxxi), SEQ ID NO: 3210 in (xxxii), SEQ ID NO: 3310 in (xxxiii), SEQ ID NO: 3410 in (xxxiv), SEQ ID NO: 3510 in (xxxv), SEQ ID NO: 3610 in (xxxvi), SEQ ID NO: 3710 in (xxxvii), SEQ ID NO: 3810 in (xxxviii),SEQ ID NO: 3910 in (xxxix), 4010 in (xl), 4110 in (xli), 4210 in (xlii), 4310 in (xliii), 4410 in (xliv), 4510 in (xlv), 4610 in (xlvi), 4630 in (xlvi-a), 4640 in (xlvi-b), 4650 in (xlvi-c), 4660 in (xlvi-d), in (xlvi-e) Sequence ID 4670, Sequence ID 4710 in (xlvii), Sequence ID 4810 in (xlviii), Sequence ID 4910 in (xlix), Sequence ID 5010 in (l), Sequence ID 5110 in (li), Sequence ID 5210 in (lii), Sequence ID 5310 in (liii), Sequence ID 5410 in (liv), Sequence ID 5510 in (lv), Sequence ID 5610 in (lvi), Sequence ID 5710 in (lvii), Sequence ID 5730 in (lvii-a), Sequence ID in (lvii-b) Number 5740, SEQ ID NO: 5750 in (lvii-c), SEQ ID NO: 5760 in (lvii-d), SEQ ID NO: 5770 in (lvii-e), SEQ ID NO: 5780 in (lvii-f), SEQ ID NO: 5810 in (lviii), SEQ ID NO: 5910 in (lix), SEQ ID NO: 6010 in (lx), SEQ ID NO: 6110 in (lxi), SEQ ID NO: 6130 in (lxi-a), SEQ ID NO: 6140 in (lxi-b), SEQ ID NO: 6150 in (lxi-c), SEQ ID NO: 6160 in (lxi-d), (l Sequence ID 6170 in (lxii), Sequence ID 6210 in (lxii), Sequence ID 6310 in (lxiii), Sequence ID 6410 in (lxiv), Sequence ID 6510 in (lxv), Sequence ID 6610 in (lxvi), Sequence ID 6710 in (lxvii), Sequence ID 6810 in (lxviii), Sequence ID 6830 in (lxviii-a), Sequence ID 6840 in (lxviii-b), Sequence ID 6850 in (lxviii-c), Sequence ID 6860 in (lxviii-d),SEQ ID NOs: 6870 in (lxviii-e), 6880 in (lxviii-f), 6910 in (lxix), 7010 in (lxx), 7030 in (lxx-a), 7040 in (lxx-b), 7050 in (lxx-c), 7060 in (lxx-d), 7070 in (lxx-e), 7080 in (lxx-f), 7110 in (lxxi), 7210 in (lxxii), 7310 in (lxxiii), 7410 in (lxxiv), 7510 in (lxxv), 7610 in (lxxvi), (lxxvii It may include, or consist of, the following: ) with sequence number 7710, sequence number 7810 in (lxxviii), or sequence number 7910 in (lxxix), sequence number 8010 in (lxxx), sequence number 8110 in (lxxxi), sequence number 8210 in (lxxxii), sequence number 8310 in (lxxxiii), sequence number 8330 in (lxxxiii-a), sequence number 8340 in (lxxxiii-b), sequence number 8350 in (lxxxiii-c), sequence number 8360 in (lxxxiii-d), sequence number 8370 in (lxxxiii-e), sequence number 8380 in (lxxxiii-f), or sequence number 8410 in (lxxxiv).

[0046] In certain embodiments of (B) above, the amino acid sequence of VH-1 may, in some cases, include or consist of SEQ ID NO: 7010 in (1) or SEQ ID NO: 8310 in (2).

[0047] In some embodiments, the anti-human CD28 antibody or antigen-binding antibody fragment according to this disclosure may be (a) an immunoglobulin (Ig) format or a semi-antibody variant thereof, optionally an IgG, IgA, IgE, IgD, or IgM format, and optionally an IgG1, IgG2, IgG3, or IgG4 format; (b) an antibody fragment antigen-binding region (Fab) format, a Fab' format, an F(ab')2 format, an F(ab')3 format, and / or a variable fragment (Fv) format; (c) a single-stranded fragment variable region (scFv) format, a tandem scFv format, a diabody format, a triabody format, a tetrabody format, or an scFv-Fc format. (d) a mat, scFv-CH format, minibody format, scFv-zipper format, diabody-Fc format, diabody-CH format, any of the aforementioned semi-antibody variants, and / or single-chain Fab (scFab) format, (d) heavy-chain-only antibody (HCAb) format, nanobody-Fc format, nanobody-CH format, single-chain nanobody-CH format, camel Ig format, and / or IgNAR format, or any of the aforementioned single-chain variants, and / or (e) single-domain antibody (sdAb) format, nanobody format, tandem nanobody format.

[0048] In some embodiments, the anti-human CD28 antibody or antigen-binding antibody fragment according to the present disclosure may include VH-1 and VL-1, and the anti-human CD28 antibody or antigen-binding antibody fragment is (a) a heavy chain containing VH-1 and a light chain containing VL-1, and optionally the antibody or antigen-binding antibody fragment comprises (a-1) the heavy chain and light chain, (a-2) an Ig molecule comprising two of the heavy chain and two of the light chains, or a polymer of the Ig molecule, and / or (a-3) a heavy chain containing VH-1 and a light chain containing VL-1, comprising IgG, IgA, IgE, IgD, or IgM, optionally IgG1, IgG2, IgG3, or IgG4, and / or (b) Fab containing VH-1 and VL-1, F containing VH-1 and VL-1 ab', F(ab')2 including VH-1 and VL-1, F(ab')3 including VH-1 and VL-1, and / or Fv including VH-1 and VL-1, (c)scFv including VH-1 and VL-1, tandem scFv including VH-1 and VL-1, diamond body including VH-1 and VL-1, tria body including VH-1 and VL-1, tetra body including VH- It may include or consist of scFv-Fc including 1 and VL-1, scFv-CH including VH-1 and VL-1, minibody including VH-1 and VL-1, scFv-zipper including VH-1 and VL-1, diabody-Fc including VH-1 and VL-1, diabody-CH including VH-1 and VL-1, and / or scFab including VH-1 and VL-1.

[0049] In some embodiments, the anti-human CD28 antibody or antigen-binding antibody fragment according to the present disclosure may contain VH-1, and the anti-human CD28 antibody or antigen-binding antibody fragment may contain (d) an HCAb containing VH-1, a nanobody-Fc containing VH-1, a nanobody-CH containing VH-1, a camel Ig containing VH-1, an IgNAR containing VH-1, and / or any single-strand variant of the foregoing, and / or (e) an sdAb containing VH-1, a nanobody containing VH-1, and / or a tandem nanobody containing VH-1, or consist of these.

[0050] In some embodiments, an anti-human CD28 antibody or antigen-binding antibody fragment according to this disclosure may (a) bind to mouse CD28 and / or cynomolgus monkey CD28.

[0051] In some embodiments, the anti-human CD28 antibody or antigen-binding antibody fragment according to this disclosure is (b) optionally measured by biolayer interferometry (BLI), and further optionally performed in Examples 3 and / or 12, at physiological pH or pH 7.4, in concentrations of less than approximately 1 μM, less than approximately 500 nM, less than approximately 200 nM, less than approximately 100 nM, less than approximately 50 nM, less than approximately 20 nM, less than approximately 10 nM, less than approximately 5 nM, less than approximately 2 nM, less than approximately 1 nM, and less than approximately 500 pM. Less than, about 1μM, about 500nM, about 200nM, about 100nM, about 50nM, about 20nM, about 10nM, about 5nM, about 2nM, about 1nM, about 500pM, about 200pM, about 100nM~1nM, about 50nM~1nM, about 20nM~1 nM, about 10nM to 1nM, about 5nM to 1nM, about 2nM to 1nM, about 10nM to 500pM, about 5nM to 500pM, about 2nM to 500pM, about 1nM to 500pM, about 1nM to 200pM, or about 500pM to about 200pM. D It can bind to human CD28.

[0052] In some embodiments, the anti-human CD28 antibody or antigen-binding antibody fragment according to this disclosure is (c) optionally measured by BLI, and further optionally carried out in Example 3, at an acidic pH or pH 6.0, with a K content of less than approximately 1 μM, less than approximately 500 nM, less than approximately 200 nM, less than approximately 100 nM, less than approximately 50 nM, less than approximately 20 nM, less than approximately 10 nM, less than approximately 5 nM, less than approximately 2 nM, less than approximately 1 nM, approximately 1 μM, approximately 500 nM, approximately 200 nM, approximately 100 nM, approximately 50 nM, approximately 20 nM, approximately 10 nM, approximately 5 nM, approximately 2 nM, or approximately 1 nM. D It can bind to human CD28.

[0053] In some embodiments, the anti-human CD28 antibody or antigen-binding antibody fragment according to this disclosure is (d) optionally measured by BLI, and further optionally carried out in Example 3, at acidic pH or pH 6.0 compared to physiological pH or pH 7.4, optionally about 1.5 times, about 2 times, about 3 times, about 4 times, about 5 times, about 6 times, about 7 times, about 8 times, about 9 times, about 10 times, about 12 times, about 15 times, about 20 times, about 25 times, about 30 times, about 35 times, about 40 times, about 45 times, about 50 times, about 60 times, about 70 times, about 80 times, about 90 times, about 100 times, about 200 times, about 300 times, about 400 times, about 500 times, about 600 times, about 700 times, about 800 times, about 90 times, or about 1000 times, or at least that much lower K at acidic pH or pH 6.0. D It can bind to human CD28.

[0054] In some embodiments, the anti-human CD28 antibody or antigen-binding antibody fragment according to this disclosure may (e) optionally be measured by BLI, and further optionally be carried out in Example 3, bind to human CD28 at an acidic pH or pH 6.0, but not bind to human CD28 at a physiological pH or pH 7.4.

[0055] In some embodiments, the anti-human CD28 antibody or antigen-binding antibody fragment according to this disclosure may (f) not bind to mouse or murine CD28 as measured by BLI, or as performed in Examples 3 and / or 12, or may have a K content of approximately 10 nM, 20 nM, 50 nM, 100 nM, 200 nM, 50 nM, 100 nM, 200 nM, 500 nM, or 1 μM. D It binds to mouse or mouse family CD28.

[0056] In some embodiments, the anti-human CD28 antibody or antigen-binding antibody fragment according to this disclosure may (g) not bind to the human CD28 monomer as measured by BLI, or as performed in Examples 3 and / or 12, or may contain K+ of about 1 nM, about 10 nM, about 20 nM, about 50 nM, about 100 nM, about 200 nM, about 500 nM, about 1 μM, about 1 nM, about 10 nM, about 20 nM, about 50 nM, about 100 nM, about 200 nM, about 500 nM, or about 1 μM. D It can bind to the human CD28 monomer.

[0057] In some embodiments, anti-human CD28 antibodies or antigen-binding antibody fragments according to this disclosure can bind more efficiently to human CD28-expressing cells, optionally Jurkat cells and / or human CD28-CHO cells, than (h) when measured optionally by flow cytometry, optionally based on median fluorescence intensity and / or normalized cell binding values, and optionally performed according to Examples 5 and / or 13.

[0058] In some embodiments, anti-human CD28 antibodies or antigen-binding antibody fragments according to this disclosure may exhibit a multispecific reagent (PSR) score of (i) < 0.1 (clean), 0.10 ≤ score < 0.33 (low), 0.33 ≤ score < 0.66 (medium), or 0.00, as measured by a PSR assay, as optionally performed in Examples 6 and / or 14.

[0059] In some embodiments, anti-human CD28 antibodies or antigen-binding antibody fragments according to this disclosure may exhibit hydrophobic interaction chromatography (HIC) retention times (RT) of RT < 9.5 min, RT < 10.0 min, or RT < 10.5 min (clean or low), or 10.5 min ≤ RT < 11.5 min (medium), as measured by HIC, as optionally carried out in Examples 6 and / or 14.

[0060] In some embodiments, the anti-human CD28 antibody or antigen-binding antibody fragment according to the present disclosure may exhibit a melting temperature (Tm) of less than about 45°C, less than about 50°C, less than about 55°C, less than about 60°C, less than about 65°C, less than about 70°C, less than about 75°C, less than about 80°C, less than about 85°C, greater than about 45°C, greater than about 50°C, greater than about 55°C, greater than about 60°C, greater than about 65°C, greater than about 70°C, greater than about 75°C, greater than about 80°C, greater than 85°C, about 45°C, about 50°C, about 55°C, about 60°C, about 65°C, about 70°C, about 75°C, about 80°C, or about 85°C, as can be optionally measured by differential scanning fluorescence (DSF) and as can be optionally carried out in Examples 6 and / or 14.

[0061] In some embodiments, an anti-human CD28 antibody or antigen-binding antibody fragment according to this disclosure can stimulate (1) T cells.

[0062] In certain embodiments, such T cell stimulation may be determined by (l-1) an increase in CD69 expression of only about 5%, about 10%, about 15%, about 20%, about 25%, about 30%, about 35%, about 40%, about 45%, about 50%, about 55%, about 60%, about 65%, about 70%, about 75%, about 80%, about 85%, about 90%, about 95%, about 100%, about 150%, about 200%, about 250%, about 300%, about 350%, about 400%, about 450%, or 500%, based on an increase in mean fluorescence intensity (MFI), as (l-1) arbitrarily measured by flow cytometry.

[0063] In certain embodiments, such T cell stimulation is (l-2) optionally measured by an immunoassay, such as an enzyme-linked immunosorbent assay (ELISA), by an optionally selected immunoassay, such as by an optionally selected immunosorbent assay, such as by an optionally selected immunosorbent assay (ELISA), by an optionally selected immunosorbent assay, such as by an optionally selected immunosorbent assay (ELISA), by an optionally selected immunosorbent assay (ELISA), by an optionally selected immunosorbent assay (ELISA), by an optionally selected immunosorbent assay (ELISA), by an optionally selected immunosorbent assay (ELISA), by an optionally selected immunosorbent assay (ELISA), by an optionally selected immunosorbent assay (ELISA), by an optionally selected immunosorbent assay (ELISA), by an optionally selected immunosorbent assay (ELISA), by an optionally selected immunosorbent assay (ELISA), by an optionally selected immunosorbent assay (ELISA), by an optionally selected immunosorbent assay (ELISA), by an optionally selected immunosorbent assay (ELISA), by an optionally selected immunosorbent assay (ELISA), by an optionally selected immunosorbent assay (ELISA), by an optionally selected immunosorbent assay (ELISA), by an optionally selected immunosorbent assay (1-2 This can be determined by an arbitrarily selected increase in IL-2 emissions of approximately 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 100%, 150%, 200%, 250%, 300%, 350%, 400%, 450%, or 500%, as measured by [unspecified method].

[0064] In certain embodiments, such T cell stimulation may be determined by an increase in transcriptional activation, as performed in Example 7, as measured using the CD28 Bioassay (Promega, TM633), when T cells are incubated with (1-3) an anti-human CD28 antibody or antigen-binding antibody fragment, and optionally with an anti-CD3 antibody, compared to T cell incubation without an anti-human CD28 antibody or antigen-binding antibody fragment, with or without an anti-CD3 antibody, optionally with an anti-human CD28 antibody or antigen-binding antibody fragment.

[0065] In one embodiment, the present disclosure provides a multispecific antibody. The multispecific antibody may include (1) a first antigen-binding region (ABR-1) that binds to human CD28, wherein ABR-1 contains either the anti-human CD28 antibody or the antigen-binding antibody fragment described above, and (2) a second antigen-binding region (ABR-2) that binds to a second antigen.

[0066] In some embodiments, ABR-2 may include a second heavy chain variable domain (VH-2) comprising a second heavy chain complementarity determining region (CDR) 1 (CDRH1-2), a second heavy chain CDR2 (CDRH2-2), and a second heavy chain CDR3 (CDRH3-2), and / or a second light chain variable domain (VL-2) comprising a second light chain CDR1 (CDRL1-2), a second light chain CDR2 (CDRL2-2), and a second light chain CDR3 (CDRL3-2).

[0067] In some embodiments, the second antigen may be optionally the same as or different from CD28 (or human CD28). If different, the first and second specificities of the multispecific antibody may be the epitope of CD28 and another epitope of CD28, respectively.

[0068] In some embodiments, the multispecific antibody may be bispecific, triplicate, quadruple, or quintuple specific, or may have more than quintuple specificity.

[0069] In some embodiments, the multispecific antibody may be bivalent, trivalent, tetravalent, pentavalent, or have a higher valency. In some embodiments, the multispecific antibody may bind to CD28 monovalent, bivalent, trivalent, tetravalent, or pentavalent, or with a higher valency. In some embodiments, the multispecific antibody may bind to the second antigen monovalent, bivalent, trivalent, tetravalent, or pentavalent, or with a higher valency.

[0070] In some embodiments, the second antigen may be any one of (a) human differentiation cluster 3 (CD3), (b) cancer antigen, optionally tumor-specific antigen (TSA) or tumor-associated antigen (TAA), (c) human CD28, or (d) an antigen selected from those listed in Table 3, and / or (c) any one of the cancer antigens selected from those listed in Table 3, optionally one of the TSAs or one of the TAAs, or may include these.

[0071] In certain embodiments, the second antigen may be CD3 or may contain CD3.

[0072] In certain embodiments, ABR-2 may include VH-2 and / or VL-2, and may include a CDR amino acid sequence according to any one of those listed in Table 4B.

[0073] In certain embodiments, in the VH-2 in ABR-2, (a) the amino acid sequence of CDRH1-2 may include, or consist of, one of the heavy chain complementarity determination region 1 (CDRH1) amino acid sequences contained in any one of the heavy chain variable domain (VH) amino acid sequences listed in Table 4A, and / or one of the CDRH1 amino acid sequences listed in Table 4B; (b) the amino acid sequence of CDRH2-2 may include, or consist of, one of the heavy chain complementarity determination region 2 (CDRH2) amino acid sequences contained in any one of the VH amino acid sequences listed in Table 4A, and / or one of the CDRH2 amino acid sequences listed in Table 4B; and / or (c) the amino acid sequence of CDRH3-2 may include, or consist of, one of the heavy chain complementarity determination region 3 (CDRH3) amino acid sequences contained in any one of the VH amino acid sequences listed in Table 4A, and / or one of the CDRH3 amino acid sequences listed in Table 4B; and / or

[0074] In a particular embodiment, in the VL-2 in ABR-2, (d) the amino acid sequence of CDRL1-2 may include, or consist of, the light chain complementarity determination region 1 (CDRL1) amino acid sequence contained in any one of the light chain variable domain (VL) amino acid sequences listed in Table 4A, and / or any one of the CDRL1 amino acid sequences listed in Table 4B; (c) the amino acid sequence of CDRL2-2 may include, or consist of, the light chain complementarity determination region 2 (CDRL2) contained in any one of the VL amino acid sequences listed in Table 4A, and / or any one of the CDRL2 amino acid sequences listed in Table 4B; and / or (f) the amino acid sequence of CDRL3-2 may include, or consist of, the light chain complementarity determination region 3 (CDRL3) contained in any one of the VL amino acid sequences listed in Table 4A, and / or any one of the CDRL3 amino acid sequences listed in Table 4B.

[0075] In some embodiments, in a multispecific antibody according to this disclosure, ABR-2 may include (a) a set of heavy chain CDR amino acid sequences of a first anti-CD3 antibody selected from the antibodies listed in Tables 4A to 4E, (b) a set of light chain CDR amino acid sequences of a first anti-CD3 antibody selected from the antibodies listed in Tables 4A to 4E, (c) a set of heavy chain and light chain CDR amino acid sequences of a first anti-CD3 antibody selected from the antibodies listed in Tables 4A to 4E, and / or (d) a set of heavy chain CDR amino acid sequences of a first anti-CD3 antibody selected from the antibodies listed in Tables 4A to 4E, and a set of light chain CDR amino acid sequences of a second anti-CD3 antibody selected from the antibodies listed in Tables 4A to 4E. The first and second anti-CD3 antibodies may be the same antibody or not. In certain embodiments, ABR-2 may include (a) a set of heavy chain CDR amino acid sequences of ADI-26906 or ADI-26921. In certain embodiments, ABR-2 may include (b) a set of light chain CDR amino acid sequences of ADI-26906 or ADI-26921. In certain embodiments, ABR-2 may include (c) a set of heavy chain and light chain CDR amino acid sequences of ADI-26906 or ADI-26921. In certain embodiments, ABR-1 and ABR-2 may have the same VL sequence (i.e., a common VL). In certain embodiments, ABR-1 may include a set of heavy chain and light chain CDR amino acid sequences (such as those included in its VH and VL) of any one of antibody numbers 59 to 69, and ABR-2 may include a set of heavy chain and light chain CDR amino acid sequences (such as those included in its VH and VL) of ADI-26921. In certain embodiments, ABR-1 may include a set of heavy and light chain CDR amino acid sequences (such as those included in its VH and VL) of antibody number 61 or 68, and ABR-2 may include a set of heavy and light chain CDR amino acid sequences (such as those included in its VH and VL) of ADI-26921.

[0076] In some embodiments, a multispecific antibody according to the disclosure comprising ABR-2 comprising VH-2 and VL-2, wherein (1) the amino acid sequences of CDRH1-2, CDRH2-2, and CDRH3-2 in VH-2 of ABR-2 comprise or consist of the amino acid sequences of CDRH1, CDRH2, and CDRH3 contained in VH of a first anti-CD3 antibody, respectively, and (2) the amino acid sequences of CDRL1-2, CDRL2-2, and CDRL3-2 in VL-2 of ABR-2 comprise or consist of the amino acid sequences of CDRL1, CDRL2, and CDRL3 contained in VL of the first anti-CD3 antibody, the first anti-CD3 antibody being one selected from the antibodies listed in Tables 4A to 4E. In certain embodiments, the first anti-CD3 antibody may be ADI-26906 or ADI-26921. In certain embodiments, ABR-1 and ABR-2 may have the same VL sequence (i.e., a common VL). In certain embodiments, VL-1 and VL-2 may comprise a set of light chain CDR amino acid sequences (such as those contained in the VL) of ADI-26921. In some cases, ABR-1 may comprise a set of heavy chain and light chain CDR amino acid sequences (such as those contained in its VH and VL) of any one of antibody numbers 59 to 69, and ABR-2 may comprise a set of heavy chain and light chain CDR amino acid sequences (such as those contained in its VH and VL) of ADI-26921. In certain cases, ABR-1 may comprise a set of heavy chain and light chain CDR amino acid sequences (such as those contained in its VH and VL) of antibody number 61 or 68, and ABR-2 may comprise a set of heavy chain and light chain CDR amino acid sequences (such as those contained in its VH and VL) of ADI-26921.

[0077] In some embodiments, ABR-2 may also include VH-2 and VL-2, and the amino acid sequences of CDRH1-2, CDRH2-2, CDRH3-2, CDRL1-2, CDRL2-2, and CDRL3-2 include or consist of the amino acid sequences of CDRH1, CDRH2, CDRH3, CDRL1, CDRL2, and CDRL3 of the first anti-CD3 antibody, the first anti-CD3 antibody being one selected from the antibodies listed in Tables 4A to 4E.

[0078] In certain embodiments, the first anti-CD3 antibody may be ADI-26906 or ADI-26921.

[0079] In certain embodiments, the multispecific antibody may include VH-2 and / or VL-2, wherein the amino acid sequence of VH-2 includes, or consists of, an amino acid sequence selected from any one of the VH amino acid sequences listed in Table 4A, or a variant thereof having at least about 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity, and / or the amino acid sequence of VL-2 includes, or consists of, an amino acid sequence selected from any one of the VL amino acid sequences listed in Table 4A, or a variant thereof having at least about 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity.

[0080] In certain embodiments, the amino acid sequences of VH-2 and VL-2 may have at least about 80%, at least about 85%, at least about 90%, at least about 91%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, or at least about 99% sequence identity with the respective amino acid sequences of VH and VL of the first anti-CD3 antibody. In certain embodiments, the first anti-CD3 antibody may be ADI-26906 or ADI-26921.

[0081] In certain embodiments, ABR-2 may include a variable domain pair according to any of those listed in Table 4A. In some cases, ABR-2 may include the VH and VL of ADI-26906 or ADI-26921. In certain cases, ABR-1 may include a VH pair and a VL pair of any one of antibody numbers 59 to 69, and ABR-2 may include a VH pair and a VL pair of ADI-26921. In certain cases, ABR-1 may include a VH pair and a VL pair of antibody number 61 or 68, and ABR-2 may include a VH pair and a VL pair of ADI-26921.

[0082] In certain embodiments, the amino acid sequences of VH-2 and VL-2 in ABR-2 may include, or consist of, the respective amino acid sequences of VH and VL of the first anti-CD3 antibody.

[0083] In a particular embodiment, in any of the multispecific antibodies described above, (1) ABR-1 is (a) a heavy chain containing VH-1 and a light chain containing VL-1, and optionally ABR-1 contains (a-1) the heavy chain and light chain, (a-2) an Ig molecule containing two of the heavy chains and two of the light chains, or a polymer of the Ig molecule, and / or (a-3) IgG, IgA, IgE, IgD, or I (b) gM, a heavy chain containing VH-1 and a light chain containing VL-1, optionally containing IgG1, IgG2, IgG3, or IgG4, or consisting thereof, (b) Fab containing VH-1 and VL-1, Fab' containing VH-1 and VL-1, F(ab')2 containing VH-1 and VL-1, F(ab')3 containing VH-1 and VL-1, and / or Fv containing VH-1 and VL-1, (c) scFv containing VH-1 and VL-1, VH-1 and Tandem scFv including VL-1, Diabody including VH-1 and VL-1, Triabody including VH-1 and VL-1, Tetrabody including VH-1 and VL-1, scFv-Fc including VH-1 and VL-1, scFv-CH including VH-1 and VL-1, Minibody including VH-1 and VL-1, scFv-Zipper including VH-1 and VL-1, Diabody-Fc including VH-1 and VL-1, including VH-1 and VL-1 (d) a diabody-CH and / or scFab containing VH-1 and VL-1, (d) an HCAb containing VH-1, a nanobody-Fc containing VH-1, a nanobody-CH containing VH-1, a camel Ig containing VH-1, an IgNAR containing VH-1, and / or any single-stranded variant of the above, and / or (e) an sdAb containing VH-1, a nanobody containing VH-1, and / or a tandem nanobody containing VH-1.

[0084] In a particular embodiment, in any of the multispecific antibodies described above, (2) ABR-2 is (a) a heavy chain containing VH-2 and a light chain containing VL-2, and optionally ABR-2 contains (a-1) the heavy chain and light chain, (a-2) an Ig molecule containing two of the heavy chain and two of the light chain, or a polymer of the Ig molecule, and / or (a-3) IgG, IgA, IgE, IgD, or (b) a heavy chain containing VH-2 and a light chain containing VL-2, which optionally contain or consist of IgM, IgG1, IgG2, IgG3, or IgG4, (b) Fab containing VH-2 and VL-2, Fab' containing VH-2 and VL-2, F(ab')2 containing VH-2 and VL-2, F(ab')3 containing VH-2 and VL-2, and / or Fv containing VH-2 and VL-2, (c) scFv containing VH- Tandem scFv including 2 and VL-2, Diabody including VH-2 and VL-2, Triabody including VH-2 and VL-2, Tetrabody including VH-2 and VL-2, scFv-Fc including VH-2 and VL-2, scFv-CH including VH-2 and VL-2, Minibody including VH-2 and VL-2, scFv-Zipper including VH-2 and VL-2, Diabody-Fc including VH-2 and VL-2, VH-2 and VL-2 (d) a diabody-CH containing VH-2 and VL-2, and / or scFab containing VH-2 and VL-2, (d) an HCAb containing VH-2, a nanobody-Fc containing VH-2, a nanobody-CH containing VH-2, a camel Ig containing VH-2, an IgNAR containing VH-2, and / or any single-stranded variant of the above, and / or (e) an sdAb containing VH-2, a nanobody containing VH-2, and / or a tandem nanobody containing VH-2.

[0085] In some cases, ABR-1 and ABR-2 may associate or link with each other via a linker, optionally a peptide linker, and optionally a flexible peptide linker. In some cases, ABR-1 and ABR-2 may associate or link with each other via one or more disulfide bonds. In some cases, ABR-1 and ABR-2 may associate or link with each other directly.

[0086] In certain embodiments, the multispecific antibody may include any one of Figures 1-6, optionally any one of Figures 2-6, and optionally any one of Figures 2A-2M, 4A-4C, 5A-5N, and 6. In certain cases, the multispecific antibody may include the structure in the box in Figure 2G.

[0087] In some cases, in any of the multispecific antibodies described above, (1) ABR-1 may include at least one Ig constant domain, optionally one or more of heavy chain constant domain 1 (CH1), heavy chain constant domain 2 (CH2), heavy chain constant domain 3 (CH3), and / or light chain constant domain (CL), and / or a fragment crystallizable (Fc) region, optionally (a) CH1, CH2, and / or CH3 may individually be of the IgG, IgA, IgE, IgD, or IgM class, optionally of the IgG1, IgG2, IgG3, and / or IgG4 subclass, (b) CL may be of the kappa isotype (CLκ) or lambda isotype (CLλ), and / or (c) the Fc region may be of the IgG, IgA, IgE, IgD, or IgM class, optionally of the IgG1, IgG2, IgG3, and / or IgG4 subclass.

[0088] In some cases, in any of the multispecific antibodies described above, (2) ABR-2 may include at least one Ig constant domain, optionally one or more of CH1, CH2, CH3, and / or CL, and / or an Fc region, optionally (a) CH1, CH2, and / or CH3 may individually be of the IgG, IgA, IgE, IgD, or IgM class, optionally of the IgG1, IgG2, IgG3, and / or IgG4 subclass, (b) CL is CLκ or CLλ, and / or (c) the Fc region may be of the IgG, IgA, IgE, IgD, or IgM class, optionally of the IgG1, IgG2, IgG3, and / or IgG4 subclass.

[0089] In some cases, the multispecific antibodies may contain a common light chain, and / or VL-1 and VL-2 may have the same or essentially the same amino acid sequence. In certain cases, the second antigen is human CD3, and the amino acid sequences of VL-1 and VL-2 individually have at least about 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity with the amino acid sequence of VL of ADI-26921 (SEQ ID NO: 13270). In certain cases, the amino acid sequences of VL-1 and VL-2 individually contain or consist of SEQ ID NO: 1327.

[0090] In some cases, the multispecific antibody may include one or more of the following: (4-i) a heavy chain constant region (CH), optionally CH1, which is modified to promote pairing with CLκ rather than CLλ, and optionally the CH1 modification is one of those described in WO2021 / 067404; (4-ii) CH, optionally CH1, which is modified to promote pairing with CLλ rather than CLκ, and optionally the CH1 modification is one of those described in WO2021 / 067404; CH, optionally CH1; and / or (4-iii) CH, optionally CH1. CH, optionally CH1, and / or (4-iv) at least two CHs having different amino acid sequences, optionally at least two CH3s having different amino acid sequences, wherein the CH3 operation is configured to promote heteromer pairing between two CHs rather than homomer pairing, optionally at least two CH3s having different amino acid sequences, wherein the CH3 operation is configured to promote heteromer pairing between two CHs rather than homomer pairing, optionally at least two CH3s having different amino acid sequences, wherein the CH3 operation is configured to promote heteromer pairing between two CHs rather than homomer pairing, optionally at least two CH3s having different amino acid sequences, wherein the CH3 operation is configured to promote heteromer pairing between two CHs rather than homomer pairing, optionally at least two CH3s having different amino acid sequences, optionally at least two CH3s having different amino acid sequences.

[0091] In some embodiments, any of the multispecific antibodies described above may include a third antigen-binding region (ABR-3) that binds to a third antigen. In some embodiments, any of the multispecific antibodies described above may include an ABR-3 that includes a third heavy chain variable domain (VH-3) comprising a third heavy chain complementarity-determining region (CDR) 1 (CDRH1-3), a third heavy chain CDR2 (CDRH2-3), and a third heavy chain CDR3 (CDRH3-3), and / or a third light chain variable domain (VL-3) comprising a third light chain CDR1 (CDRL1-3), a third light chain CDR2 (CDRL2-3), and a third light chain CDR3 (CDRL3-3).

[0092] In some embodiments, the third antigen may be optionally the same as or different from CD28 (or human CD28) and / or the second antigen. If the third antigen is CD28, ABR-1 and ABR-3 may bind to the same epitope of CD28 or to different epitopes of CD28. If the third antigen is the same as the second antigen, ABR-2 and ABR-3 may bind to the same epitope of the second antigen or to different epitopes of the second antigen.

[0093] In some embodiments, the third antigen may be any one of (a) human CD3, (b) cancer antigen, optionally TSA or TAA, (c) human CD28, (d) an antigen selected from those listed in Table 3, and / or (e) any one of the cancer antigens selected from those listed in Table 3, optionally one of the TSAs or one of the TAAs, or may include these.

[0094] In some embodiments, the third antigen may be CD3 or may contain CD3.

[0095] In certain embodiments, ABR-3 may include VH-3 and / or VL-3, and may include a CDR amino acid sequence according to any one of those listed in Table 4B.

[0096] In certain embodiments, ABR-3 may include the VH-3, and (a) the amino acid sequences of CDRH1-3 include, or consist of, one of the heavy chain complementarity-determining region 1 (CDRH1) amino acid sequences contained in any one of the heavy chain variable domain (VH) amino acid sequences listed in Table 4A, and / or one of the CDRH1 amino acid sequences listed in Table 4B; (b) the amino acid sequences of CDRH2-3 include, or consist of, one of the heavy chain complementarity-determining region 2 (CDRH2) amino acid sequences contained in any one of the VH amino acid sequences listed in Table 4A, and / or one of the CDRH2 amino acid sequences listed in Table 4B; and / or (c) the amino acid sequences of CDRH3-3 include, or consist of, one of the heavy chain complementarity-determining region 3 (CDRH3) amino acid sequences contained in any one of the VH amino acid sequences listed in Table 4A, and / or one of the CDRH3 amino acid sequences listed in Table 4B.

[0097] In certain embodiments, ABR-3 may include the VL-3, and (d) the amino acid sequences of CDRL1-3 include, or consist of, one of the light chain complementarity-determining region 1 (CDRL1) amino acid sequences included in any one of the light chain variable domain (VL) amino acid sequences listed in Table 4A, and / or one of the CDRL1 amino acid sequences listed in Table 4B; (c) the amino acid sequences of CDRL2-3 include, or consist of, one of the light chain complementarity-determining region 2 (CDRL2) amino acid sequences included in any one of the VL amino acid sequences listed in Table 4A, and / or one of the CDRL2 amino acid sequences listed in Table 4B; and / or (f) the amino acid sequences of CDRL3-3 include, or consist of, one of the light chain complementarity-determining region 3 (CDRL3) amino acid sequences included in any one of the VL amino acid sequences listed in Table 4A, and / or one of the CDRL3 amino acid sequences listed in Table 4B.

[0098] In some embodiments, ABR-3 may include (a) a set of heavy chain CDR amino acid sequences of a third anti-CD3 antibody selected from the antibodies listed in Tables 4A to 4E, (b) a set of light chain CDR amino acid sequences of a third anti-CD3 antibody selected from the antibodies listed in Tables 4A to 4E, (c) a set of heavy and light chain CDR amino acid sequences of a third anti-CD3 antibody selected from the antibodies listed in Tables 4A to 4E, and / or (d) a set of heavy chain CDR amino acid sequences of a third anti-CD3 antibody selected from the antibodies listed in Tables 4A to 4E, and a set of light chain CDR amino acid sequences of a fourth anti-CD3 antibody selected from the antibodies listed in Tables 4A to 4E. In certain embodiments, the third anti-CD3 antibody may be ADI-26906 or ADI-26921. In (d), the third and / or fourth anti-CD3 antibody may be ADI-26906 or ADI-26921. In (d), the third anti-CD3 antibody and the fourth anti-CD3 antibody may or may not be the same antibody.

[0099] In certain embodiments, ABR-3 may include a set of heavy chain CDR amino acid sequences contained in the VH of ADI-26906 or ADI-26921. In some cases, ABR-3 may include a set of light chain CDR amino acid sequences contained in the VL of ADI-26906 or ADI-26921. In certain embodiments, ABR-3 may include a set of heavy chain and light chain CDR amino acid sequences contained in the VH and VL of ADI-26906, or the VH and VL of ADI-26921. In some cases, ABR-1 may include a set of heavy chain and light chain CDR amino acid sequences contained in the VH and VL of any one of antibody numbers 59 to 69, and ABR-3 may include a set of heavy chain and light chain CDR amino acid sequences contained in the VH and VL of ADI-26921. In certain cases, ABR-1 may include a set of heavy and light chain CDR amino acid sequences contained in the VH and VL of antibody number 61 or 68, and ABR-3 may include a set of heavy and light chain CDR amino acid sequences contained in the VH and VL of ADI-26921.

[0100] In some embodiments, ABR-3 may also contain VH-3 and VL-3, where (1) the amino acid sequences of CDRH1-3, CDRH2-3, and CDRH3-3 in VH-3 of ABR-3 contain or consist of the amino acid sequences of CDRH1, CDRH2, and CDRH3 contained in VH of the third anti-CD3 antibody, respectively, and (2) the amino acid sequences of CDRL1-3, CDRL2-3, and CDRL3-3 in VL-3 of ABR-3 contain or consist of the amino acid sequences of CDRL1, CDRL2, and CDRL3 contained in VL of the third anti-CD3 antibody, respectively, and the third anti-CD3 antibody is one selected from the antibodies listed in Tables 4A to 4E. In certain embodiments, the third anti-CD3 antibody may be ADI-26906 or ADI-26921.

[0101] In some embodiments, the amino acid sequences of CDRH1-3, CDRH2-3, CDRH3-3, CDRL1-3, CDRL2-3, and CDRL3-3 of VL-3 and VH-3 of ABR-3 may include, or consist of, the amino acid sequences of CDRH1, CDRH2, CDRH3, CDRL1, CDRL2, and CDRL3 of a third anti-CD3 antibody, the third anti-CD3 antibody being one selected from the antibodies listed in Tables 4A to 4E. In certain embodiments, the third anti-CD3 antibody may be ADI-26906 or ADI-26921.

[0102] In certain embodiments, the amino acid sequence of VH-3 of ABR-3 may include, or consist of, an amino acid sequence selected from any one of the VH amino acid sequences listed in Table 4A, or a variant thereof having at least about 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity, and / or the amino acid sequence of VL-3 of ABR-3 may include, or consist of, an amino acid sequence selected from any one of the VL amino acid sequences listed in Table 4A, or a variant thereof having at least about 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity.

[0103] In a particular embodiment, the amino acid sequences of VH-3 and VL-3 of ABR-3 may have at least about 80%, at least about 85%, at least about 90%, at least about 91%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, or at least about 99% sequence identity with the respective amino acid sequences of VH and VL of the third anti-CD3 antibody.

[0104] In certain embodiments, the third anti-CD3 antibody may be ADI-26906 or ADI-26921.

[0105] In certain embodiments, ABR3 may include a variable domain pair according to any of those listed in Table 4A. In some cases, ABR3 may include a variable domain pair of ADI-26906 or ADI-26921. In certain cases, ABR-1 may include a VH pair and a VL pair of any one of antibody numbers 59 to 69, and ABR-3 may include a VH pair and a VL pair of ADI-26921. In certain cases, ABR-1 may include a VH pair and a VL pair of antibody number 61 or 68, and ABR-3 may include a VH pair and a VL pair of ADI-26921.

[0106] In certain embodiments, the amino acid sequences of VH-3 and VL-3 may include, or consist of, the respective amino acid sequences of VH and VL of the third anti-CD3 antibody.

[0107] In a particular embodiment, in any of the multispecific antibodies described above, ABR-3 is (a) a heavy chain containing VH-3 and a light chain containing VL-3, and optionally ABR-3 is (a-1) composed of the heavy chain and light chain, (a-2) an Ig molecule containing two of the heavy chain and two of the light chain, or a polymer of the Ig molecule, and / or (a-3) IgG, IgA, IgE, IgD, or Ig M, a heavy chain containing VH-3 and a light chain containing VL-3, optionally containing or consisting of IgG1, IgG2, IgG3, or IgG4, (b) Fab containing VH-3 and VL-3, Fab' containing VH-3 and VL-3, F(ab')2 containing VH-3 and VL-3, F(ab')3 containing VH-3 and VL-3, and / or Fv containing VH-3 and VL-3, (c) scFv containing VH- Includes tandem scFv with 3 and VL-3, diamond body with VH-3 and VL-3, tria body with VH-3 and VL-3, tetra body with VH-3 and VL-3, scFv-Fc with VH-3 and VL-3, scFv-CH with VH-3 and VL-3, mini body with VH-3 and VL-3, scFv-zipper with VH-3 and VL-3, diamond body-Fc with VH-3 and VL-3, and VH-3 and VL-3. (d) a diabody-CH and / or scFab containing VH-3 and VL-3, (d) an HCAb containing VH-3, a nanobody-Fc containing VH-3, a nanobody-CH containing VH-3, a camel Ig containing VH-3, an IgNAR containing VH-3, and / or any single-stranded variant of the above, and / or (e) an sdAb containing VH-3, a nanobody containing VH-3, and / or a tandem nanobody containing VH-3.

[0108] In some cases, (f) ABR-1 and ABR-2 may associate or link with each other via a linker, optionally a peptide linker, optionally a flexible peptide linker, or via one or more disulfide bonds. In some cases, (g) ABR-1 and ABR-3 are associated or linked with each other via a linker, optionally a peptide linker, optionally a flexible peptide linker, or via one or more disulfide bonds. In some cases, (h) ABR-2 and ABR-3 are associated or linked with each other via a linker, optionally a peptide linker, optionally a flexible peptide linker, or via one or more disulfide bonds.

[0109] In certain embodiments, the multispecific antibody may include any one of Figures 1-6, optionally any one of Figures 2-6, and optionally any one of Figures 3A-3B, 4A-4C, 5A-5N, and 6. In certain cases, the multispecific antibody may include the structure in the box in Figure 2G.

[0110] In some cases, in any of the multispecific antibodies described above, (1) ABR-3 may include at least one Ig constant domain, optionally one or more of CH1, CH2, CH3, and / or CL, and / or an Fc region, optionally (a) CH1, CH2, and / or CH3 being of the IgG, IgA, IgE, IgD, or IgM class, optionally of the IgG1, IgG2, IgG3, and / or IgG4 subclass, (b) CL is CLκ or CLλ, and / or (c) the Fc region being of the IgG, IgA, IgE, IgD, or IgM class, optionally of the IgG1, IgG2, IgG3, and / or IgG4 subclass.

[0111] In some cases, in any of the multispecific antibodies described above, (2) the multispecific antibody may contain a common light chain and / or VL-1 and VL-2 have the same or essentially the same amino acid sequence and / or VL-1 and VL-3 have the same or essentially the same amino acid sequence and / or VL-2 and VL-3 have the same or essentially the same amino acid sequence.

[0112] In certain cases, (i) the second antigen may be human CD3, and the amino acid sequences of VL-1 and VL-2 may, individually, have at least about 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity with the amino acid sequence of VL of ADI-26921 (sequence number 13270), or may contain or consist of sequence number 13270. In certain cases, (ii) the third antigen may be human CD3, and the amino acid sequences of VL-1 and VL-3 may, individually, have at least about 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity with the amino acid sequence of VL of ADI-26921 (SEQ ID NO: 13270), or may contain or consist of SEQ ID NO: 13270.

[0113] In some cases, in any of the multispecific antibodies described above, (3) the multispecific antibody may include one or more of the following: (3-i) a heavy chain constant region (CH), optionally CH1, which is modified to promote pairing with CLκ rather than CLλ, and optionally the CH1 modification is one of those described in WO2021 / 067404; (3-ii) CH, optionally CH1, which is modified to promote pairing with CLλ rather than CLκ, and optionally the CH1 modification is one of those described in WO2021 / 067404; CH, optionally CH1, and / or (3-iii) CH, optionally CH1, which is optionally CH1, which is modified to promote pairing with a modified CL contained in a multispecific antibody rather than with another CL, and optionally the combination of CH modification and CL modification is one of those described in WO2022 / 150787, and / or (3-iv) two CHs having different amino acid sequences, optionally two CH3s having different amino acid sequences, which are modified to promote heteromer pairing between the two CHs rather than homomer pairing, and optionally the CH3 modification is one of those described in WO2022 / 150785, and optionally two CH3s.

[0114] In some embodiments, any of the multispecific antibodies described above may include a fourth antigen-binding region (ABR-4) that binds to a fourth antigen. In some embodiments, any of the multispecific antibodies described above may include an ABR-4 that includes a fourth heavy chain variable domain (VH-4) comprising a fourth heavy chain complementarity-determining region (CDR) 1 (CDRH1-4), a fourth heavy chain CDR2 (CDRH2-4), and a fourth heavy chain CDR3 (CDRH3-4), and / or a fourth light chain variable domain (VL-4) comprising a fourth light chain CDR1 (CDRL1-4), a fourth light chain CDR2 (CDRL2-4), and a fourth light chain CDR3 (CDRL3-4).

[0115] In some embodiments, the fourth antigen may be, optionally, the same as or different from CD28 (or human CD28), the second antigen, and / or the third antigen. If the fourth antigen is CD28, ABR-1 and ABR-4 may bind to the same epitope of CD28 or to different epitopes of CD28. If the fourth antigen is the same as the second antigen, ABR-2 and ABR-4 may bind to the same epitope of the second antigen or to different epitopes of the second antigen. If the fourth antigen is the same as the third antigen, ABR-3 and ABR-4 may bind to the same epitope of the third antigen or to different epitopes of the third antigen.

[0116] In some embodiments, the fourth antigen may include (a) human differentiation cluster 3 (CD3), (b) cancer antigen, optionally TSA or TAA, (c) human CD28, (d) any one antigen selected from those listed in Table 3, and / or (e) any one cancer antigen selected from those listed in Table 3, optionally one TSA or one TAA, or all of these.

[0117] In some embodiments, the fourth antigen may include CD3, or may not include CD3.

[0118] In certain embodiments, ABR-4 may include VH-4 and / or VL-4, and may include a CDR amino acid sequence according to any one of those listed in Table 4B.

[0119] In certain embodiments, ABR-4 may include the VH-4, and (a) the amino acid sequences of CDRH1-4 include, or consist of, one of the heavy chain complementarity determination region 1 (CDRH1) amino acid sequences contained in any one of the heavy chain variable domain (VH) amino acid sequences listed in Table 4A, and / or one of the CDRH1 amino acid sequences listed in Table 4B; (b) the amino acid sequences of CDRH2-4 include, or consist of, one of the heavy chain complementarity determination region 2 (CDRH2) amino acid sequences contained in any one of the VH amino acid sequences listed in Table 4A, and / or one of the CDRH2 amino acid sequences listed in Table 4B; and / or (c) the amino acid sequences of CDRH3-4 include, or consist of, one of the heavy chain complementarity determination region 3 (CDRH3) amino acid sequences contained in any one of the VH amino acid sequences listed in Table 4A, and / or one of the CDRH3 amino acid sequences listed in Table 4B; and / or

[0120] In certain embodiments, ABR-4 may include the VL-4, and (d) the amino acid sequences of CDRL1-4 include, or consist of, one of the light chain complementarity-determining region 1 (CDRL1) amino acid sequences included in any one of the light chain variable domain (VL) amino acid sequences listed in Table 4A, and / or one of the CDRL1 amino acid sequences listed in Table 4B; (c) the amino acid sequences of CDRL2-4 include, or consist of, one of the light chain complementarity-determining region 2 (CDRL2) amino acid sequences included in any one of the VL amino acid sequences listed in Table 4A, and / or one of the CDRL2 amino acid sequences listed in Table 4B; and / or (f) the amino acid sequences of CDRL3-4 include, or consist of, one of the light chain complementarity-determining region 3 (CDRL3) amino acid sequences included in any one of the VL amino acid sequences listed in Table 4A, and / or one of the CDRL3 amino acid sequences listed in Table 4B.

[0121] In certain embodiments, ABR-4 may include (a) a set of heavy chain CDR amino acid sequences of a fifth anti-CD3 antibody selected from the antibodies listed in Tables 4A-4E, (b) a set of light chain CDR amino acid sequences of a fifth anti-CD3 antibody selected from the antibodies listed in Tables 4A-4E, (c) a set of heavy chain and light chain CDR amino acid sequences of a fifth anti-CD3 antibody selected from the antibodies listed in Tables 4A-4E, and / or (d) a set of heavy chain CDR amino acid sequences of a fifth anti-CD3 antibody selected from the antibodies listed in Tables 4A-4E, and a set of light chain CDR amino acid sequences of a sixth anti-CD3 antibody selected from the antibodies listed in Tables 4A-4E. In certain embodiments, the fifth anti-CD3 antibody may be ADI-26906 or ADI-26921. In (d), the fifth and / or sixth anti-CD3 antibodies may be ADI-26906 or ADI-26921. In (d), the fifth anti-CD3 antibody and the sixth anti-CD3 antibody may or may not be the same antibody.

[0122] In certain embodiments, ABR-4 may include a set of heavy chain CDR amino acid sequences contained in the VH of ADI-26906 or ADI-26921. In some cases, ABR-4 may include a set of light chain CDR amino acid sequences contained in the VL of ADI-26906 or ADI-26921. In certain embodiments, ABR-4 may include a set of heavy chain and light chain CDR amino acid sequences contained in the VH and VL of ADI-26906, or the VH and VL of ADI-26921. In some cases, ABR-1 may include a set of heavy chain and light chain CDR amino acid sequences contained in the VH and VL of any one of antibody numbers 59 to 69, and ABR-4 may include a set of heavy chain and light chain CDR amino acid sequences contained in the VH and VL of ADI-26921. In certain cases, ABR-1 may include a set of heavy and light chain CDR amino acid sequences contained in the VH and VL of antibody number 61 or 68, and ABR-4 may include a set of heavy and light chain CDR amino acid sequences contained in the VH and VL of ADI-26921.

[0123] In some embodiments, ABR-4 may include (1) the amino acid sequences of CDRH1-4, CDRH2-4, and CDRH3-4 of ABR-4's VH-4 containing or consisting of the amino acid sequences of CDRH1, CDRH2, and CDRH3 contained in the VH of the fifth anti-CD3 antibody, respectively, and (2) the amino acid sequences of CDRL1-4, CDRL2-4, and CDRL3-4 of ABR-4's VL-4 containing or consisting of the amino acid sequences of CDRL1, CDRL2, and CDRL3 contained in the VL of the fifth anti-CD3 antibody, the fifth anti-CD3 antibody being one selected from the antibodies listed in Tables 4A to 4E. In certain embodiments, the fifth anti-CD3 antibody may be ADI-26906 or ADI-26921.

[0124] In some embodiments, the amino acid sequences of CDRH1-4, CDRH2-4, CDRH3-4, CDRL1-4, CDRL2-4, and CDRL3-4 of VH-4 and VL-4 in ABR-4 may include, or consist of, the amino acid sequences of CDRH1, CDRH2, CDRH3, CDRL1, CDRL2, and CDRL3 of a fifth anti-CD3 antibody, and the fifth anti-CD3 antibody is selected from the antibodies listed in Tables 4A to 4E.

[0125] In a particular embodiment, the amino acid sequence of VH-4 may include, or consist of, an amino acid sequence selected from any one of the VH amino acid sequences listed in Table 4A, or a variant thereof having at least about 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity, and / or the amino acid sequence of VL-4 may include, or consist of, an amino acid sequence selected from any one of the VL amino acid sequences listed in Table 4A, or a variant thereof having at least about 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity.

[0126] In certain embodiments, the amino acid sequences of VH-4 and VL-4 may have at least about 80%, at least about 85%, at least about 90%, at least about 91%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, or at least or at least about 99% sequence identity with respect to the respective amino acid sequences of VH and VL of the fifth anti-CD3 antibody.

[0127] In certain embodiments, the fifth anti-CD3 antibody may be ADI-26906 or ADI-26921.

[0128] In certain embodiments, ABR-4 may include a variable domain pair according to any of those listed in Table 4A. In some cases, ABR-4 may include the VH and VL of ADI-26906 or ADI-26921. In some cases, ABR-1 may include a VH pair and a VL pair of any one of antibody numbers 59 to 69, and ABR-4 may include a VH pair and a VL pair of ADI-26921. In certain cases, ABR-1 may include a VH pair and a VL pair of antibody number 61 or 68, and ABR-4 may include a VH pair and a VL pair of ADI-26921.

[0129] In certain embodiments, the amino acid sequences of VH-4 and VL-4 may include, or consist of, the respective amino acid sequences of VH and VL of the fifth anti-CD3 antibody.

[0130] Some of the ABR-4s are (a) heavy chains containing VH-4 and light chains containing VL-4, and optionally contain an antibody or antigen-binding antibody fragment that (a-1) consists of the heavy chain and light chain, (a-2) contains an Ig molecule or a polymer of the Ig molecule comprising two of the heavy chains and two of the light chains, and / or (a-3) contains IgG, IgA, IgE, IgD, or IgM, optionally IgG1, IgG2, (b) a heavy chain containing VH-4 and a light chain containing VL-4, comprising or consisting of IgG3 or IgG4, (b) Fab containing VH-4 and VL-4, Fab' containing VH-4 and VL-4, F(ab')2 containing VH-4 and VL-4, F(ab')3 containing VH-4 and VL-4, and / or Fv containing VH-4 and VL-4, (c) scFv containing VH-4 and VL-4, tandem containing VH-4 and VL-4 Diabody including scFv, VH-4 and VL-4, Triabody including VH-4 and VL-4, Tetrabody including VH-4 and VL-4, scFv-Fc including VH-4 and VL-4, scFv-CH including VH-4 and VL-4, Minibody including VH-4 and VL-4, scFv-Zipper including VH-4 and VL-4, Diabody-Fc including VH-4 and VL-4, Diabody including VH-4 and VL-4 (d) an scFab comprising body-CH and / or VH-4 and VL-4, an HCAb comprising VH-4, a nanobody-Fc comprising VH-4, a nanobody-CH comprising VH-4, a camel Ig comprising VH-4, an IgNAR comprising VH-4, and / or any single-stranded variant of the foregoing, and / or (e) an sdAb comprising VH-4, a nanobody comprising VH-4, and / or a tandem nanobody comprising VH-4.

[0131] In some cases, (f) ABR-1 and ABR-2 may associate or link with each other via a linker, optionally a peptide linker, optionally a flexible peptide linker, or one or more disulfide bonds. In some cases, (g) ABR-1 and ABR-3 may associate or link with each other via a linker, optionally a peptide linker, optionally a flexible peptide linker, or one or more disulfide bonds. In some cases, (h) ABR-1 and ABR-4 may associate or link with each other via a linker, optionally a peptide linker, optionally a flexible peptide linker, or one or more disulfide bonds. In some cases, (i) ABR-2 and ABR-3 may associate or link with each other via a linker, optionally a peptide linker, optionally a flexible peptide linker, or one or more disulfide bonds. In some cases, (j) ABR-2 and ABR-4 may associate or link with each other via a linker, optionally a peptide linker, optionally a flexible peptide linker, or via one or more disulfide bonds. In some cases, (k) ABR-3 and ABR-4 may associate or link with each other via a linker, optionally a peptide linker, optionally a flexible peptide linker, or via one or more disulfide bonds. In some cases, ABR-4 may directly associate or link with one or more of ABR-1, ABR-2, and / or ABR-4.

[0132] In certain embodiments, the multispecific antibody may include any one of Figures 1-6, optionally any one of Figures 4-6, and optionally any one of Figures 4A-4C, 5A-5N, and 6. In certain cases, the multispecific antibody may include the structure shown in the box in Figure 2G.

[0133] In some cases, in any of the multispecific antibodies described above, (1) ABR-4 comprises at least one Ig constant domain, optionally one or more of CH1, CH2, CH3, and / or CL, and / or an Fc region, and optionally (a) CH1, CH2, and / or CH3 are each of the IgG, IgA, IgE, IgD, or IgM class, optionally of the IgG1, IgG2, IgG3, and / or IgG4 subclass, (b) CL is CLκ or CLλ, and / or (c) the Fc region is of the IgG, IgA, IgE, IgD, or IgM class, optionally of the IgG1, IgG2, IgG3, and / or IgG4 subclass.

[0134] In some cases, in any of the multispecific antibodies described above, (2) the multispecific antibody may contain a common light chain and / or VL-1 and VL-2 have the same or essentially the same amino acid sequence and / or VL-1 and VL-3 have the same or essentially the same amino acid sequence and / or VL-1 and VL-4 have the same or essentially the same amino acid sequence and / or VL-2 and VL-3 have the same or essentially the same amino acid sequence and / or VL-2 and VL-4 have the same or essentially the same amino acid sequence and / or VL-3 and VL-4 have the same or essentially the same amino acid sequence. In certain cases, (i) the second antigen may be human CD3, and the amino acid sequences of VL-1 and VL-2 may, individually, have at least about 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity with the amino acid sequence of VL of ADI-26921 (sequence number 13270), or may contain or consist of sequence number 13270; (ii) the third antigen may be human CD3, and the amino acid sequences of VL-1 and VL-3 may, individually, have at least about 80%, 85% sequence identity with the amino acid sequence of VL of ADI-26921 (sequence number 13270). , may have 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity, or may include or be derived from sequence number 13270, and / or (iii) the fourth antigen may be human CD3, and the amino acid sequences of VL-1 and VL-4 may, individually, have at least about 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity with the amino acid sequence of VL of ADI-26921 (sequence number 13270), or may include or be derived from sequence number 1327.

[0135] For example, in any of the embodiments described herein, if the sequences of VL-1 and VL-2 (or VL-1 and VL-3, and / or VL-1 and VL-4) are the same, such VL domains having the same sequence may be referred to as a “common VL domain” or “cVL” domain. Similarly, light chains having the same sequence may be referred to as a “common light chain” or “cLC”.

[0136] In some cases, in any of the multispecific antibodies described above, (3) the multispecific antibody may include one or more of the following: (3-i) a heavy chain constant region (CH), optionally CH1, which is modified to promote pairing with CLκ rather than CLλ, and optionally the CH1 modification is one of those described in WO2021 / 067404; (3-ii) CH, optionally CH1, which is modified to promote pairing with CLλ rather than CLκ, and optionally the CH1 modification is one of those described in WO2021 / 067404; CH, optionally CH1, and / or (3-iii) CH, optionally CH1, which is optionally CH1, which is modified to promote pairing with a modified CL contained in a multispecific antibody rather than with another CL, and optionally the combination of CH modification and CL modification is one of those described in WO2022 / 150787, and / or (3-iv) two CHs having different amino acid sequences, optionally two CH3s having different amino acid sequences, which are modified to promote heteromer pairing between the two CHs rather than homomer pairing, and optionally the CH3 modification is one of those described in WO2022 / 150785, and optionally two CH3s.

[0137] In one embodiment, the present disclosure provides a multispecific antibody which may optionally be any of the multispecific antibodies described above.

[0138] In some embodiments, the multispecific antibody comprises (A) at least one antigen-binding region (ABR-A) that binds to antigen A, and (Ai) at least one heavy chain A optionally comprising a heavy chain variable domain A (VH-A) and a heavy chain constant domain A (CH-A) from the N-terminus to the C-terminus, wherein CH-A optionally comprises (a) a heavy chain constant domain 1A (CH1-A), a hinge (Hinge-A), a heavy chain constant domain 2A (CH2-A), and / or a heavy chain constant domain 3A (CH3-A), and / or (b) CH1-A, Hinge-A, CH2-A, and CH3-A optionally comprising at least one heavy chain A, and optionally comprising (A-ii) a light chain variable domain A (VL-A) and a light chain constant domain A (CL-A), and heavy chain A and light chain A (present The present invention may include at least one antigen-binding region (ABR-A) that binds to antigen A and optionally pairs with each other via at least one disulfide bond, and at least one antigen-binding region B (ABR-B) that includes (B) a Fab (Fab-B) that binds to antigen B, and comprising (Bi) a heavy chain variable domain B (VH-B) and a heavy chain constant domain B (CH-B) that includes at least one heavy chain constant domain 1B (CH1-B), and (B-ii) a light chain variable domain B (VL-B) and a light chain constant domain B (CL-B), wherein the heavy chain B and light chain B optionally pair with each other via at least one disulfide bond to form an antigen-binding region that binds to antigen B, and at least one antigen-binding region B (ABR-B) that includes a Fab (Fab-B) that binds to antigen B.

[0139] In some cases, (a) heavy chain B, optionally the C-terminus or N-terminus of heavy chain B, is associated or linked to (a-1) heavy chain A, optionally the N-terminus or C-terminus of heavy chain A, or (a-2) light chain A (if present), optionally the N-terminus or C-terminus of light chain A (if present), optionally via a linker, optionally a peptide linker, and optionally a flexible peptide linker.

[0140] In some cases, (b) light chain B, optionally the C-terminus or N-terminus of light chain B, is associated or linked to (b-1) light chain A (if present), optionally the N-terminus or C-terminus of light chain A (if present), and / or (b-2) heavy chain A, optionally the N-terminus or C-terminus of heavy chain A, optionally via a linker, optionally further optionally via a peptide linker, and optionally further optionally via a flexible peptide linker.

[0141] In certain embodiments, the multispecific antibody may include structures optionally according to any one of 2A-2I, 3A-3B, 4A-4C, and 5A-5I, as illustrated in any one of Figures 1-6, and further optionally, antigen B may be the same as or different from antigen A. In certain embodiments, the multispecific antibody may include structures illustrated in the box structure of Figure 2G.

[0142] In some embodiments, the multispecific antibody comprises (A) at least one antigen-binding region (ABR-A) that binds to antigen A, and (Ai) at least one heavy chain A optionally comprising a heavy chain variable domain A (VH-A) and a heavy chain constant domain A (CH-A) from the N-terminus to the C-terminus, wherein CH-A optionally comprises (a) a heavy chain constant domain 1A (CH1-A), a hinge (Hinge-A), a heavy chain constant domain 2A (CH2-A), and / or a heavy chain constant domain 3A (CH3-A), and / or (b) at least one heavy chain A optionally comprising CH1-A, Hinge-A, CH2-A, and CH3-A from the N-terminus to the C-terminus, and optionally (A-ii) a light chain variable domain A The device may also include: at least one light chain A comprising (VL-A) and light chain constant domain A (CL-A), wherein heavy chain A and light chain A (if present) optionally pair with each other via at least one disulfide bond to form an antigen-binding region that binds to antigen A; and at least one antigen-binding region B (ABR-B) comprising (B) scFv (scFv-B) that binds to antigen B, wherein (Bi) heavy chain variable domain B (VH-B) and (B-ii) light chain variable domain B (VL-B), comprising scFv (scFv-B) that binds to antigen B.

[0143] In some cases, (a) the C-terminus of VH-B is coupled to the N-terminus of VL-B, and optionally scFv-B contains VH-B, a linker, and VL-B from the N-terminus to the C-terminus, or (b) the C-terminus of VL-B is coupled to the N-terminus of VH-B, and optionally scFv-B contains VL-B, a linker, and VH-B from the N-terminus to the C-terminus.

[0144] In some cases, scFv-B, optionally the C-terminus or N-terminus of scFv-B, may be associated or linked (1) to heavy chain A, optionally the N-terminus or C-terminus of heavy chain A, and / or (2) to light chain A (if present), optionally the N-terminus or C-terminus of light chain A (if present), optionally via a linker, optionally a peptide linker, and optionally a flexible peptide linker.

[0145] In certain embodiments, the multispecific antibody may include structures optionally according to any one of Figures 2A, 2F, 2J, 3A-3B, 4A-4C, 5C-5G, and 5J-5N, as illustrated in any one of Figures 1-6, wherein antigen B is either the same as or different from antigen A.

[0146] In some embodiments, the multispecific antibody comprises (A) at least one antigen-binding region (ABR-A) that binds to antigen A, and (Ai) at least one heavy chain A optionally comprising heavy chain variable domain A (VH-A) and heavy chain constant domain A (CH-A) from the N-terminus to the C-terminus, wherein CH-A optionally comprises (a) heavy chain constant domain 1A (CH1-A), hinge (hinge-A), heavy chain constant domain 2A (CH2-A), and / or heavy chain constant domain Antigen binding comprising: 3A(CH3-A), and / or (b)CH1-A, hinge-A, CH2-A, and CH3-A optionally from the N-terminus to the C-terminus, at least one heavy chain A, and optionally (A-ii)light chain variable domain A (VL-A) and light chain constant domain A (CL-A), wherein the heavy chain A and light chain A (if present) optionally pair with each other via at least one disulfide bond to bind to antigen A. (B) A heavy chain B comprising (B) a heavy chain variable domain B (VH-B) and a heavy chain constant domain B (CH-B) comprising (B) a heavy chain variable domain B (VL-B) and a light chain constant domain B (CL-B), and (B-ii) a light chain variable domain B (VL-B) and a light chain constant domain B (CL-B). The invention may also include at least one antigen-binding region B (ABR-B) comprising a light chain B and an antigen-binding scFab (scFab-B), wherein (a) the C-terminus of the heavy chain B is ligated to the N-terminus of the light chain B, and optionally, the scFab-B comprises the heavy chain B, a linker, and the light chain B from the N-terminus to the C-terminus, or (b) the C-terminus of the light chain B is ligated to the N-terminus of the heavy chain B, and optionally, the scFab-B comprises the light chain B, a linker, and the heavy chain B from the N-terminus to the C-terminus.

[0147] In some cases, scFab-B, or optionally the C-terminus or N-terminus of scFab-B, is associated or linked (1) to heavy chain A, optionally the N-terminus or C-terminus of heavy chain A, and / or (2) to light chain A (if present), optionally the N-terminus or C-terminus of light chain A (if present), optionally via a linker, optionally a peptide linker, and optionally a flexible peptide linker.

[0148] In certain embodiments, the multispecific antibody may include a structure optionally according to one of Figures 2A, 2F, 2K, 3A-3B, and 4A-4C, as illustrated in any one of Figures 1-6, wherein antigen B is optionally the same as or different from antigen A.

[0149] In some embodiments, the multispecific antibody comprises (A) at least one antigen-binding region (ABR-A) that binds to antigen A, and (Ai) at least one heavy chain A optionally comprising a heavy chain variable domain A (VH-A) and a heavy chain constant domain A (CH-A) from the N-terminus to the C-terminus, wherein CH-A optionally comprises (a) a heavy chain constant domain 1A (CH1-A), a hinge (Hinge-A), a heavy chain constant domain 2A (CH2-A), and / or a heavy chain constant domain 3A (CH3-A), and / or (b) CH1-A, Hinge-A, CH2-A, and CH3-A optionally from the N-terminus to the C-terminus. The material may also include at least one heavy chain A containing at least one heavy chain A at its C-terminus, and at least one light chain A optionally containing (A-ii) a variable light chain domain A (VL-A) and a constant light chain domain A (CL-A), wherein heavy chain A and light chain A optionally pair with each other via at least one disulfide bond to form an antigen-binding region that binds to antigen A, and at least one antigen-binding region B (ABR-B) containing (B) a variable heavy chain domain B (VH-B) that binds to antigen B, and at least one antigen-binding region B (ABR-B).

[0150] In some cases, sdAb, or optionally the C-terminus or N-terminus of sdAb-B, is associated or linked (1) to heavy chain A, or optionally to the N-terminus or C-terminus of heavy chain A, and / or (2) to light chain A (if present), or optionally to the N-terminus or C-terminus of light chain A (if present), via an optionally linker, optionally a peptide linker, or optionally a flexible peptide linker.

[0151] In certain embodiments, the multispecific antibody may include a structure according to one of Figures 2-6, which is further optionally modified to omit at least one VL, as illustrated in one of Figures 1-6, and further optionally, antigen B is the same as or different from antigen A.

[0152] In some embodiments, the multispecific antibody comprises (A) at least one antigen-binding region (ABR-A) that binds to antigen A, and (Ai) at least one heavy chain A optionally comprising a heavy chain variable domain A (VH-A) and a heavy chain constant domain A (CH-A) from the N-terminus to the C-terminus, wherein CH-A optionally comprises (a) heavy chain constant domain 1A (CH1-A), hinge A (hinge-A), heavy chain constant domain 2A (CH2-A), and / or heavy chain constant domain 3A (CH3-A), and / or (b) CH1-A, hinge-A The device comprises at least one heavy chain A comprising CH2-A and CH3-A optionally from the N-terminus to the C-terminus, and at least one light chain A optionally comprising (A-ii) a variable light chain domain A (VL-A) and a constant light chain domain A (CL-A), wherein the heavy chain A and light chain A (if present) optionally pair with each other via at least one disulfide bond to form an antigen-binding region that binds to antigen A, and (B) at least one antigen-binding region that binds to antigen B An antigen-binding region (ABR-B) comprising at least one heavy chain B, which optionally includes a (Bi) heavy chain variable domain B (VH-B) and a heavy chain constant domain B (CH-B) from the N-terminus to the C-terminus, wherein CH-B optionally includes (a) a heavy chain constant domain 1B (CH1-B), hinge B (hinge-B), heavy chain constant domain 2B (CH2-B), and / or a heavy chain constant domain 3B (CH3-A), and / or (b) CH1-B, hinge-B, CH2-B, and CH3-B from the N-terminus to the C-terminus, at least The present invention may also include at least one antigen-binding region (ABR-B) that binds to antigen B, comprising one heavy chain B, and optionally one light chain B comprising a (B-ii) light chain variable domain B (VL-B) and a light chain constant domain B (CL-B), wherein the heavy chain B and light chain B (if present) optionally pair with each other via at least one disulfide bond to form an antigen-binding region that binds to antigen B, and optionally, the heavy chain A and heavy chain B optionally pair with each other via at least one disulfide bond.

[0153] In a particular embodiment, (a)(a-1) light chain A (if present) and light chain B (if present) have the same or essentially the same amino acid sequence, or are a common light chain.

[0154] In certain embodiments, (a-2)(a-2i)CH-A and / or CL-A (if present), optionally CH1-A and / or CL-A (if present) may be manipulated to promote pairing between CH-A and CL-A more than between CH-A and CL-B and / or between CH-B and CL-A, optionally (1) CL-A is CLκ and CH-A, optionally CH1-A is manipulated to promote pairing with CLκ more than CLλ, optionally CH1-A manipulation is one of those described in WO2021 / 067404, or (2) CL -A is CLλ, and CH-A, optionally CH1-A, is manipulated to promote pairing with CLλ rather than CLκ, optionally the CH1-A manipulation is one of those described in WO2021 / 067404, or (3) CH-A, optionally CH1-A, and both CL-A are manipulated to promote pairing between CH-A and CL-A rather than between CH-A and CL-B and / or between CH-B and CL-A, optionally the combination of CH-A and CL-A manipulations is one of those described in WO2022 / 150787.

[0155] In certain embodiments, (a-2)(a-2ii)CH-B and / or CL-B (if present), optionally CH1-B and / or CL-B (if present) may be manipulated to promote pairing between CH-B and CL-B more than between CH-B and CL-A and / or between CH-A and CL-B, optionally (1) CL-B is CLλ and CH-B, optionally CH1-B is manipulated to promote pairing with CLλ more than CLκ, optionally CH1-B manipulation is one of those described in WO2021 / 067404, or (2) C L-B is CLκ, and CH-B, optionally CH1-B, are manipulated to promote pairing with CLκ more than with CLλ, optionally the CH1-B manipulation is one of those described in WO2021 / 067404, or (3) CH-B, optionally CH1-B, and both CL-B are manipulated to promote pairing between CH-B and CL-B more than between CH-B and CL-A and / or between CH-A and CL-B, optionally the combination of CH-B and CL-B manipulations is one of those described in WO2022 / 150787.

[0156] In certain embodiments, (b) CH-A and / or CH-B, optionally CH3-A and / or CH3-B and / or optionally CH3-A and / or CH3-B may be manipulated to promote heteromer pairing between CH-A and CH-B more than homomer CH-A pairing and / or homomer CH-B pairing, and optionally the CH3-A and / or CH3-B manipulation is one of those described in WO2022 / 150785.

[0157] In certain embodiments, the multispecific antibody may include structures optionally according to 2G-2K, 3A-3B, 4A-4C, and 5A-5N, as illustrated in any one of Figures 1-6, and further optionally, antigen B may be the same as or different from antigen A. In certain embodiments, the multispecific antibody may include structures illustrated in the box structure of Figure 2G.

[0158] In certain embodiments, the multispecific antibody may be any of the above-described multispecific antibodies, including ABR-1 and ABR-2, where (I)(A) antigen A is human CD28, VH-A is VH-1 or includes it, and / or VL-A (if present) is VL-1 or includes it, (B) antigen B is a second antigen, VH-B is VH-2 or includes it, and / or VL-B (if present) is VL-2 or includes it, or (II)(A) antigen A is a second antigen, VH-A is VH-2 or includes it, and / or VL-A (if present) is VL-2 or includes it, (B) antigen B is human CD28, VH-B is VH-1 or includes it, and / or VL-B (if present) is VL-1 or includes it.

[0159] In some embodiments, any of the above-described multispecific antibodies, including ABR-A and ABR-B, may further include at least one antigen-binding region (ABR-C) that binds to antigen C.

[0160] In certain embodiments, ABR-C may include a Fab(Fab-C) that binds to antigen C, comprising a heavy chain C comprising a heavy chain variable domain C(VH-C) and a heavy chain constant region C(CH-C) comprising at least a heavy chain constant domain 1C(CH1-C), and a light chain C comprising a light chain variable domain C(VL-C) and a light chain constant domain C(CL-C), wherein the heavy chain C and light chain C optionally pair with each other via at least one disulfide bond.

[0161] In certain embodiments, ABR-C may include an (C-2) scFv(scFv-C) that binds to antigen C, comprising (Ci) a heavy chain variable domain C (VH-C) and (C-ii) a light chain variable domain C (VL-C), wherein (a) the C-terminus of VH-C is ligated to the N-terminus of VL-C, and optionally, the scFv-C comprises VH-C, a linker, and VL-C from the N-terminus to the C-terminus, or (b) the C-terminus of VL-C is ligated to the N-terminus of VH-C, and optionally, the scFv-C comprises VL-C, a linker, and VH-C from the N-terminus to the C-terminus.

[0162] In certain embodiments, ABR-C may include (a)(scFab-C) that binds to (C-3) antigen C, and comprises (Ci) heavy chain C comprising a heavy chain variable domain C (VH-C) and a heavy chain constant region C (CH-C) comprising at least a heavy chain constant domain 1C (CH1-C), and (C-ii) light chain C comprising a light chain variable domain C (VL-C) and a light chain constant domain C (CL-C), wherein (a) the C-terminus of heavy chain C is ligated to the N-terminus of light chain C, and optionally scFab-C comprises heavy chain C, a linker, and light chain B from the N-terminus to the C-terminus, or (b) the C-terminus of light chain C is ligated to the N-terminus of heavy chain C, and optionally scFab-C comprises light chain C, a linker, and heavy chain C from the N-terminus to the C-terminus.

[0163] In certain embodiments, ABR-C may further include at least one antigen-binding region (ABR-C) comprising at least one sdAb (sdFab-C) that binds to antigen C and includes a (C-4) heavy chain variable domain C (VH-C).

[0164] In certain embodiments, the multispecific antibody comprises a structure optionally according to one of Figures 2-6, as illustrated in any one of Figures 1-6, wherein antigen C is optionally the same as or different from antigen A and / or antigen B.

[0165] In some cases, in (C-1), Fab-C is associated with or linked to ABR-A and / or ABR-B, and optionally, (a) heavy chain C, optionally the C-terminus or N-terminus of heavy chain C may be associated with or linked to ABR-A and / or ABR-B, optionally, the C-terminus and / or N-terminus of heavy chain A and / or light chain A (if present) of ABR-A, and / or the C-terminus and / or N-terminus of heavy chain B (if present) and / or light chain B (if present), scFv-B (if present), scFab-B (if present), or sdAb-B (if present), optionally via a linker (b) The light chain C, optionally the C-terminus or N-terminus of the light chain C, may be associated with or linked to ABR-A and / or ABR-B, and optionally the heavy chain A of ABR-A and / or the C-terminus and / or N-terminus of the light chain A (if present), and / or the heavy chain B of ABR-B (if present) and / or the light chain B (if present), scFv-B (if present), scFab-B (if present), or sdAb-B (if present) may be associated with or linked to a linker, optionally a peptide linker, and optionally a flexible peptide linker.

[0166] In some cases, in (C-2), scFv-C, optionally the C-terminus or N-terminus of scFv-C, may be associated with or linked to ABR-A and / or ABR-B, and optionally, the C-terminus and / or N-terminus of the heavy chain A and / or light chain A (if present) of ABR-A, and / or the C-terminus and / or N-terminus of the heavy chain B (if present) and / or light chain B (if present), scFv-B (if present), scFab-B (if present), or sdAb-B (if present) may be associated with or linked to a linker, optionally a peptide linker, and optionally a flexible peptide linker.

[0167] In some cases, in (C-3), scFab-C, optionally the C-terminus or N-terminus of scFab-C, may be associated with or linked to ABR-A and / or ABR-B, and optionally, the C-terminus and / or N-terminus of the heavy chain A and / or light chain A (if present) of ABR-A, and / or the C-terminus and / or N-terminus of the heavy chain B (if present) and / or light chain B (if present), scFv-B (if present), scFab-B (if present), or sdAb-B (if present) may be associated with or linked to ABR-A and / or the C-terminus and / or N-terminus of ABR-B, optionally via a linker, optionally via a peptide linker, and optionally via a flexible peptide linker.

[0168] In some cases, in (C-4), the C-terminus or N-terminus of sdFab-C, optionally sdAb-C, may be associated with or linked to ABR-A and / or ABR-B, and optionally, the C-terminus and / or N-terminus of the heavy chain A and / or light chain A (if present) of ABR-A, and / or the C-terminus and / or N-terminus of the heavy chain B (if present) and / or light chain B (if present), scFv-B (if present), scFab-B (if present), or sdAb-B (if present) may be associated with or linked to and / or light chain B (if present) of ABR-B, optionally sdAb-B (if present), optionally sdAb-B (if present), optionally sdAb-B (if present), optionally sdAb-B (if present), optionally sdAb-B (if present), optionally sdAb-B (if present), optionally sdAb-B (if present), optionally sdAb-C, optionally sdAb-C, optionally sdAb-C, optionally sdAb-C, optionally sdAb-C, optionally sdAb-C, optionally sdAb-C, optionally sdAb-C, optionally sdAb-C, optionally sdAb-C, optionally sdAb-B, optionally sdAb-C, optionally sdAb-B, optionally sdAb-C, optionally sdAb-B, optionally sdAb-B, optionally sdAb-B, optionally

[0169] In certain embodiments, the multispecific antibody may be any of the above-described multispecific antibodies, including ABR-1, ABR-2, and ABR-3, (I)(A) antigen A is human CD28, VH-A is VH-1 or includes it, and / or VL-A (if present) is VL-1 or includes it; (B) antigen B is a second antigen, VH-B is VH-2 or includes it, and / or VL-B (if present) is VL-2 or includes it; (C) antigen C is a third antigen, VH-C is VH-3 or includes it, and / or VL-C (if present) is VL-3 or includes it.

[0170] In certain embodiments, the multispecific antibody may be any of the above-described multispecific antibodies, including ABR-1, ABR-2, and ABR-3, (II)(A) Antigen A is human CD28, VH-A is VH-1 or includes it, and / or VL-A (if present) is VL-1 or includes it; (B) Antigen B is a third antigen, VH-B is VH-3 or includes it, and / or VL-B (if present) is VL-3 or includes it; (C) Antigen C is a second antigen, VH-C is VH-2 or includes it, and / or VL-C (if present) is VL-2 or includes it.

[0171] In certain embodiments, the multispecific antibody may be any of the above-described multispecific antibodies, including ABR-1, ABR-2, and ABR-3, (III)(A) Antigen A is a second antigen, where VH-A is VH-2 or includes it, and / or VL-A (if present) is VL-2 or includes it; (B) Antigen B is human CD28, where VH-B is VH-1 or includes it, and / or VL-B (if present) is VL-1 or includes it; (C) Antigen C is a third antigen, where VH-C is VH-3 or includes it, and / or VL-C (if present) is VL-3 or includes it.

[0172] In certain embodiments, the multispecific antibody may be any of the above-described multispecific antibodies, including ABR-1, ABR-2, and ABR-3, (IV)(A) Antigen A is a second antigen, where VH-A is VH-2 or includes it, and / or VL-A (if present) is VL-2 or includes it; (B) Antigen B is a third antigen, where VH-B is VH-3 or includes it, and / or VL-B (if present) is VL-3 or includes it; (C) Antigen C is human CD28, where VH-C is VH-1 or includes it, and / or VL-C (if present) is VL-1 or includes it.

[0173] In certain embodiments, the multispecific antibody may be any of the above-mentioned multispecific antibodies, including ABR-1, ABR-2, and ABR-3, (V)(A) Antigen A is a third antigen, VH-A is VH-3 or contains it, and / or VL-A (if present) is VL-3 or contains it, (B) Antigen B is human CD28, VH-B is VH-1 or contains it, and / or VL-B (if present) is VL-1 or contains it, (C) Antigen C is a second antigen, VH-C is VH-2 or contains it, and / or VL-C (if present) is VL-2 or contains it, or

[0174] In certain embodiments, the multispecific antibody may be any of the above-described multispecific antibodies, including ABR-1, ABR-2, and ABR-3, (VI)(A) Antigen A is a third antigen, VH-A is VH-3 or includes it, and / or VL-A (if present) is VL-3 or includes it, (B) Antigen B is a second antigen, VH-B is VH-2 or includes it, and / or VL-B (if present) is VL-2 or includes it, (C) Antigen C is human CD28, VH-C is VH-1 or includes it, and / or VL-C (if present) is VL-1 or includes it.

[0175] In some embodiments, any of the above-described multispecific antibodies, including ABR-A and ABR-B, may further include at least one antigen-binding region (ABR-D) that binds to antigen D.

[0176] In certain embodiments, ABR-D may include a Fab(Fab-D) that binds to antigen D, comprising (D-1-i) a heavy chain D comprising a heavy chain variable domain D(VH-D) and a heavy chain constant region D(CH-D) comprising at least a heavy chain constant domain 1D(CH1-D), and (D-ii) a light chain D comprising a light chain variable domain D(VL-D) and a light chain constant domain D(CL-D), wherein the heavy chain D and light chain D optionally pair with each other via at least one disulfide bond.

[0177] In certain embodiments, ABR-D may include an (D-2) antigen D-binding scFv(scFv-D) comprising (Di) heavy chain variable domain D(VH-D) and (D-ii) light chain variable domain D(VL-D), wherein (a) the C-terminus of VH-D is ligated to the N-terminus of VL-D, and optionally scFv-D comprises VH-D, a linker, and VL-D from the N-terminus to the C-terminus, or (b) the C-terminus of VL-D is ligated to the N-terminus of VH-D, and optionally scFv-D comprises VL-D, a linker, and VH-D from the N-terminus to the C-terminus.

[0178] In certain embodiments, ABR-D may include a scFab(scFab-D) that binds to antigen D, comprising (Di) a heavy chain D comprising a heavy chain variable domain D(VH-D) and a heavy chain constant region D(CH-D) comprising at least a heavy chain constant domain 1D(CH1-D), and (D-ii) a light chain D comprising a light chain variable domain D(VL-D) and a light chain constant domain D(CL-D), wherein (a) the C-terminus of the heavy chain D is ligated to the N-terminus of the light chain D, and optionally, the scFab-D comprises a heavy chain D, a linker, and a light chain D from the N-terminus to the C-terminus, or (b) the C-terminus of the light chain D is ligated to the N-terminus of the heavy chain D, and optionally, the scFab-D comprises a light chain D, a linker, and a heavy chain D from the N-terminus to the C-terminus.

[0179] In certain embodiments, ABR-D may include an sdAb (sdFab-D) that binds to antigen D and contains a (D-4) heavy chain variable domain D (VH-D).

[0180] In certain embodiments, the multispecific antibody may include a structure optionally according to one of Figures 2-6, as illustrated in any one of Figures 1-6, wherein antigen D is optionally the same as or different from antigens A, B, and / or C.

[0181] In some cases, in (D-1), Fab-D is associated with or linked to ABR-A, ABR-B, and / or ABR-C, and optionally, (a) heavy chain D, optionally the C-terminus or N-terminus of heavy chain D is associated with or linked to ABR-A, ABR-B, and / or ABR-C, and optionally, the C-terminus and / or N-terminus of heavy chain A and / or light chain A (if present) of ABR-A, heavy chain B (if present) and / or light chain B (if present) of ABR-B, scFv-B (if present), scFab-B (if present), or sdAb-B (if present) is linked with an optionally, linker. (a) The light chain D, optionally the C-terminus or N-terminus of the light chain C, is associated with or linked to ABR-A, ABR-B, and / or ABR-C, and optionally the C-terminus and / or N-terminus of the heavy chain A and / or light chain A (if present) of ABR-A, the heavy chain B (if present) and / or light chain B (if present) of ABR-B, the scFv-B (if present), the scFab-B (if present), or the sdAb-B (if present) is associated with or linked to the C-terminus and / or N-terminus of the heavy chain C (if present) and / or light chain C (if present) of ABR-C, the scFv-C (if present), the scFab-C (if present), or the sdAb-C (if present) is associated with or linked to ABR-A, ABR-B, and / or ABR-C, optionally the C-terminus and / or N-terminus of the heavy chain A and / or light chain A (if present) of ABR-A, optionally the C-terminus and / or N-terminus of the heavy chain C and / or light chain C (if present) of ABR-C N-terminus of the light chain C (if present) is associated with or linked to ABR-A, ABR-B, and / or ABR-C, optionally the C-terminus and / or N-terminus of ABR-A and / or ABR-B, and optionally the C-terminus and / or N-terminus of ABR-A and / or ABR-B, and optionally the C

[0182] In some cases, in (D-2), scFv-D, optionally the C-terminus or N-terminus of scFv-D, is associated with or linked to ABR-A, ABR-B, and / or ABR-C, and optionally the C-terminus and / or N-terminus of heavy chain A and / or light chain A (if present) of ABR-A, heavy chain B (if present) and / or light chain B (if present) of ABR-B, scFv-B (if present), scFab-B (if present), or sdAb-B (if present) is associated with or linked to the C-terminus and / or N-terminus of heavy chain C (if present) and / or light chain C (if present) of ABR-C, scFv-C (if present), scFab-C (if present), or sdAb-C), scFv-C (if present), or sdAb-C (if present) is associated with or linked to the C-terminus and / or N-terminus of heavy chain C (if present) and / or light chain C (if present) of ABR-C, optionally the C-terminus and / or N-terminus of heavy chain C (if present) of ABR-C, optionally the C-terminus and / or N-terminus of heavy chain C (if present) of ABR-C (if present), optionally the C-terminus and / or N-terminus of heavy chain C (if present) of heavy chain C (if present), optionally the C-terminus and / or N-terminus of heavy chain C (if present

[0183] In some cases, in (D-3), scFab-D, optionally the C-terminus or N-terminus of scFab-D, is associated with or linked to ABR-A, ABR-B, and / or ABR-C, and optionally the C-terminus and / or N-terminus of heavy chain A and / or light chain A (if present) of ABR-A, heavy chain B (if present) and / or light chain B (if present) of ABR-B, scFv-B (if present), scFab-B (if present), or sdAb-B (if present) is associated with or linked to the C-terminus and / or N-terminus of heavy chain C (if present) and / or light chain C (if present) of ABR-C, scFv-C (if present), scFab-C (if present), or sdAb-C), scFv-C (if present), or sdAb-C (if present) is associated with or linked to the C-terminus and / or N-terminus of heavy chain C (if present) and / or light chain C (if present) of ABR-C, optionally the C-terminus and / or N-terminus of heavy chain C (if present) of ABR-C, optionally the C-terminus and / or N-terminus of heavy chain C (if present) of ABR-C (if present), optionally the C-terminus and / or N-terminus of heavy chain C (if present) of ABR-C (if present), optionally the C-terminus and / or N-terminus of heavy chain C (if present),

[0184] In some cases, in (D-4), the C-terminus or N-terminus of sdFab-D, optionally sdAb-D, is associated with or linked to ABR-A, ABR-B, and / or ABR-C, and optionally, the C-terminus and / or N-terminus of the heavy chain A and / or light chain A (if present) of ABR-A, the heavy chain B (if present) and / or light chain B (if present) of ABR-B, the C-terminus and / or N-terminus of scFv-B (if present), scFab-B (if present), or sdAb-B (if present), and / or the C-terminus and / or N-terminus of the heavy chain C (if present) and / or light chain C (if present) of ABR-C, scFv-C (if present), scFab-C (if present), or sdAb-C (if present) are associated with or linked to the C-terminus and / or N-terminus of ABR-A, optionally sdAb-C (if present), and optionally linked to the C-terminus and / or N-terminus of ABR-C (if present) and / or light chain C (if present), scFv-C (if present), scFab-C (if present), or sdAb-C (if present) via optionally linked to a linker, optionally sdAb-C (if present), or optionally sdAb-C (if present).

[0185] In certain embodiments, the multispecific antibody may be any of the above-described multispecific antibodies, including ABR-1, ABR-2, ABR-3, and ABR-4, where (I)(A) antigen A is human CD28, VH-A is VH-1 or includes it, and / or VL-A (if present) is VL-1 or includes it; (B) antigen B is a second antigen, VH-B is VH-2 or includes it, and / or VL-B (if present) is VL-2 or includes it; (C) antigen C is a third antigen, VH-C is VH-3 or includes it, and / or VL-C (if present) is VL-3 or includes it; (D) antigen D is a fourth antigen, VH-D is VH-4 or includes it, and / or VL-D (if present) is VL-4 or includes it.

[0186] In certain embodiments, the multispecific antibody may be any of the above-described multispecific antibodies, including ABR-1, ABR-2, ABR-3, and ABR-4, (II)(A) Antigen A is human CD28, VH-A is VH-1 or includes it, and / or VL-A (if present) is VL-1 or includes it; (B) Antigen B is a second antigen, VH-B is VH-2 or includes it, and / or VL-B (if present) is VL-2 or includes it; (C) Antigen C is a fourth antigen, VH-C is VH-4 or includes it, and / or VL-C (if present) is VL-4 or includes it; (D) Antigen D is a third antigen, VH-D is VH-3 or includes it, and / or VL-D (if present) is VL-3 or includes it.

[0187] In certain embodiments, the multispecific antibody may be any of the above-described multispecific antibodies, including ABR-1, ABR-2, ABR-3, and ABR-4, (III)(A) Antigen A is human CD28, VH-A is VH-1 or includes it, and / or VL-A (if present) is VL-1 or includes it; (B) Antigen B is a third antigen, VH-B is VH-3 or includes it, and / or VL-B (if present) is VL-3 or includes it; (C) Antigen C is a second antigen, VH-C is VH-2 or includes it, and / or VL-C (if present) is VL-2 or includes it; (D) Antigen D is a fourth antigen, VH-D is VH-4 or includes it, and / or VL-D (if present) is VL-4 or includes it.

[0188] In certain embodiments, the multispecific antibody may be any of the above-described multispecific antibodies, including ABR-1, ABR-2, ABR-3, and ABR-4, (IV)(A) Antigen A is human CD28, VH-A is VH-1 or includes it, and / or VL-A (if present) is VL-1 or includes it; (B) Antigen B is a third antigen, VH-B is VH-3 or includes it, and / or VL-B (if present) is VL-3 or includes it; (C) Antigen C is a fourth antigen, VH-C is VH-4 or includes it, and / or VL-C (if present) is VL-4 or includes it; (D) Antigen D is a second antigen, VH-D is VH-2 or includes it, and / or VL-D (if present) is VL-2 or includes it.

[0189] In certain embodiments, the multispecific antibody may be any of the above-described multispecific antibodies, including ABR-1, ABR-2, ABR-3, and ABR-4, (V)(A) Antigen A is human CD28, VH-A is VH-1 or includes it, and / or VL-A (if present) is VL-1 or includes it; (B) Antigen B is a fourth antigen, VH-B is VH-4 or includes it, and / or VL-B (if present) is VL-4 or includes it; (C) Antigen C is a second antigen, VH-C is VH-2 or includes it, and / or VL-C (if present) is VL-2 or includes it; (D) Antigen D is a third antigen, VH-D is VH-3 or includes it, and / or VL-D (if present) is VL-3 or includes it.

[0190] In certain embodiments, the multispecific antibody may be any of the above-described multispecific antibodies, including ABR-1, ABR-2, ABR-3, and ABR-4, (VI)(A) Antigen A is human CD28, VH-A is VH-1 or includes it, and / or VL-A (if present) is VL-1 or includes it; (B) Antigen B is a fourth antigen, VH-B is VH-4 or includes it, and / or VL-B (if present) is VL-4 or includes it; (C) Antigen C is a third antigen, VH-C is VH-3 or includes it, and / or VL-C (if present) is VL-3 or includes it; (D) Antigen D is a second antigen, VH-D is VH-2 or includes it, and / or VL-D (if present) is VL-2 or includes it.

[0191] In certain embodiments, the multispecific antibody may be any of the above-described multispecific antibodies, including ABR-1, ABR-2, ABR-3, and ABR-4, (VII)(A) Antigen A is a second antigen, VH-A is VH-2 or contains it, and / or VL-A (if present) is VL-2 or contains it, (B) Antigen B is human CD28, VH-B is VH-1 or contains it (C) Antigen C is the third antigen, VH-C is VH-3 or contains VH-3, and / or VL-C (if present) is VL-3 or contains VL-3, and (D) Antigen D is the fourth antigen, VH-D is VH-4 or contains VH-4, and / or VL-D (if present) is VL-4 or contains VL-4.

[0192] In certain embodiments, the multispecific antibody may be any of the above-mentioned multispecific antibodies, including ABR-1, ABR-2, ABR-3, and ABR-4, (VIII)(A) Antigen A is a second antigen, VH-A is VH-2 or contains it, and / or VL-A (if present) is VL-2 or contains it, (B) Antigen B is human CD28, VH-B is VH-1 or contains it (C) Antigen C is the fourth antigen, VH-C is VH-4 or contains VH-4, and / or VL-C (if present) is VL-4 or contains VL-4, and (D) Antigen D is the third antigen, VH-D is VH-3 or contains VH-3, and / or VL-D (if present) is VL-3 or contains VL-3.

[0193] In certain embodiments, the multispecific antibody may be any of the above-described multispecific antibodies, including ABR-1, ABR-2, ABR-3, and ABR-4, (IX)(A) Antigen A is a second antigen, where VH-A is VH-2 or includes it, and / or VL-A (if present) is VL-2 or includes it; (B) Antigen B is a third antigen, where VH-B is VH-3 or includes it, and / or VL-B (if present) is VL-3 or includes it; (C) Antigen C is human CD28, where VH-C is VH-1 or includes it, and / or VL-C (if present) is VL-1 or includes it; (D) Antigen D is a fourth antigen, where VH-D is VH-4 or includes it, and / or VL-D (if present) is VL-4 or includes it.

[0194] In certain embodiments, the multispecific antibody may be any of the above-described multispecific antibodies, including ABR-1, ABR-2, ABR-3, and ABR-4, (X)(A) Antigen A is a second antigen, where VH-A is VH-2 or includes it, and / or VL-A (if present) is VL-2 or includes it; (B) Antigen B is a third antigen, where VH-B is VH-3 or includes it, and / or VL-B (if present) is VL-3 or includes it; (C) Antigen C is a fourth antigen, where VH-C is VH-4 or includes it, and / or VL-C (if present) is VL-4 or includes it; (D) Antigen D is human CD28, where VH-D is VH-1 or includes it, and / or VL-D (if present) is VL-1 or includes it.

[0195] In certain embodiments, the multispecific antibody may be any of the above-described multispecific antibodies, including ABR-1, ABR-2, ABR-3, and ABR-4, (XI)(A) Antigen A is a second antigen, where VH-A is VH-2 or includes it, and / or VL-A (if present) is VL-2 or includes it; (B) Antigen B is a fourth antigen, where VH-B is VH-4 or includes it, and / or VL-B (if present) is VL-4 or includes it; (C) Antigen C is human CD28, where VH-C is VH-1 or includes it, and / or VL-C (if present) is VL-1 or includes it; (D) Antigen D is a third antigen, where VH-D is VH-3 or includes it, and / or VL-D (if present) is VL-3 or includes it.

[0196] In certain embodiments, the multispecific antibody may be any of the above-described multispecific antibodies, including ABR-1, ABR-2, ABR-3, and ABR-4, (XII)(A) Antigen A is a second antigen, VH-A is VH-2 or contains it, and / or VL-A (if present) is VL-2 or contains it, (B) Antigen B is a fourth antigen, VH-B is VH-4 or contains it (C) Antigen C is a third antigen, VH-C is VH-3 or contains VH-3, and / or VL-C (if present) is VL-3 or contains VL-3, and (D) Antigen D is human CD28, VH-D is VH-1 or contains VH-1, and / or VL-D (if present) is VL-1 or contains VL-1.

[0197] In certain embodiments, the multispecific antibody may be any of the above-described multispecific antibodies, including ABR-1, ABR-2, ABR-3, and ABR-4, (XIII)(A) Antigen A is a third antigen, VH-A is VH-3 or contains it, and / or VL-A (if present) is VL-3 or contains it, (B) Antigen B is human CD28, VH-B is VH-1 or contains it (C) Antigen C is the second antigen, VH-C is VH-2 or contains VH-2, and / or VL-C (if present) is VL-2 or contains VL-2, and (D) Antigen D is the fourth antigen, VH-D is VH-4 or contains VH-4, and / or VL-D (if present) is VL-4 or contains VL-4.

[0198] In certain embodiments, the multispecific antibody may be any of the above-described multispecific antibodies, including ABR-1, ABR-2, ABR-3, and ABR-4, (XIV)(A) Antigen A is a third antigen, VH-A is VH-3 or contains it, and / or VL-A (if present) is VL-3 or contains it, (B) Antigen B is human CD28, VH-B is VH-1 or contains it (C) Antigen C is the fourth antigen, VH-C is VH-4 or contains VH-4, and / or VL-C (if present) is VL-4 or contains VL-4, and (D) Antigen D is the second antigen, VH-D is VH-2 or contains VH-2, and / or VL-D (if present) is VL-2 or contains VL-2.

[0199] In certain embodiments, the multispecific antibody may be any of the above-mentioned multispecific antibodies, including ABR-1, ABR-2, ABR-3, and ABR-4, where (XV)(A) antigen A is a third antigen, VH-A is VH-3 or includes it, and / or VL-A (if present) is VL-3 or includes it, and (B) antigen B is a second antigen, VH-B is VH-2 or includes it. (C) Antigen C is human CD28, VH-C is VH-1 or contains VH-1, and / or VL-C (if present) is VL-1 or contains VH-1, and (D) Antigen D is the fourth antigen, VH-D is VH-4 or contains VH-4, and / or VL-D (if present) is VL-4 or contains VH-4.

[0200] In certain embodiments, the multispecific antibody may be any of the above-described multispecific antibodies, including ABR-1, ABR-2, ABR-3, and ABR-4, (XVI)(A) Antigen A is a third antigen, VH-A is VH-3 or contains it, and / or VL-A (if present) is VL-3 or contains it, (B) Antigen B is a second antigen, VH-B is VH-2 or contains it. (C) Antigen C is the fourth antigen, VH-C is VH-4 or contains VH-4, and / or VL-C (if present) is VL-4 or contains VH-4, and (D) Antigen D is human CD28, VH-D is VH-1 or contains VH-1, and / or VL-D (if present) is VL-1 or contains VH-1.

[0201] In certain embodiments, the multispecific antibody may be any of the above-described multispecific antibodies, including ABR-1, ABR-2, ABR-3, and ABR-4, (XVII)(A) Antigen A is a third antigen, VH-A is VH-3 or contains it, and / or VL-A (if present) is VL-3 or contains it, (B) Antigen B is a fourth antigen, VH-B is VH-4 or contains it (C) Antigen C is human CD28, VH-C is VH-1 or contains VH-1, and / or VL-C (if present) is VL-1 or contains VL-1, and (D) Antigen D is a second antigen, VH-D is VH-2 or contains VH-2, and / or VL-D (if present) is VL-2 or contains VL-2.

[0202] In certain embodiments, the multispecific antibody may be any of the above-described multispecific antibodies, including ABR-1, ABR-2, ABR-3, and ABR-4, (XVIII)(A) Antigen A is a third antigen, VH-A is VH-3 or contains it, and / or VL-A (if present) is VL-3 or contains it, (B) Antigen B is a fourth antigen, VH-B is VH-4 or contains it (C) Antigen C is a secondary antigen, VH-C is VH-2 or contains VH-2, and / or VL-C (if present) is VL-2 or contains VL-2, and (D) Antigen D is human CD28, VH-D is VH-1 or contains VH-1, and / or VL-D (if present) is VL-1 or contains VL-1.

[0203] In certain embodiments, the multispecific antibody may be any of the above-mentioned multispecific antibodies, including ABR-1, ABR-2, ABR-3, and ABR-4, (IXX)(A) antigen A is the fourth antigen, VH-A is VH-4 or contains it, and / or VL-A (if present) is VL-4 or contains it, (B) antigen B is human CD28, VH-B is VH-1 or contains it (C) Antigen C is the second antigen, VH-C is VH-2 or contains VH-2, and / or VL-C (if present) is VL-2 or contains VL-2, and (D) Antigen D is the third antigen, VH-D is VH-3 or contains VH-3, and / or VL-D (if present) is VL-3 or contains VL-3.

[0204] In certain embodiments, the multispecific antibody may be any of the above-described multispecific antibodies, including ABR-1, ABR-2, ABR-3, and ABR-4, (XX)(A) Antigen A is a fourth antigen, VH-A is VH-4 or includes it, and / or VL-A (if present) is VL-4 or includes it; (B) Antigen B is human CD28, VH-B is VH-1 or includes it, and / or VL-B (if present) is VL-1 or includes it; (C) Antigen C is a third antigen, VH-C is VH-3 or includes it, and / or VL-C (if present) is VL-3 or includes it; (D) Antigen D is a second antigen, VH-D is VH-2 or includes it, and / or VL-D (if present) is VL-2 or includes it.

[0205] In certain embodiments, the multispecific antibody may be any of the above-described multispecific antibodies, including ABR-1, ABR-2, ABR-3, and ABR-4, (XXI)(A) Antigen A is a fourth antigen, VH-A is VH-4 or contains it, and / or VL-A (if present) is VL-4 or contains it, and (B) Antigen B is a second antigen, VH-B is VH-2 or contains it. (C) Antigen C is human CD28, VH-C is VH-1 or contains VH-1, and / or VL-C (if present) is VL-1 or contains VH-1, and (D) Antigen D is a third antigen, VH-D is VH-3 or contains VH-3, and / or VL-D (if present) is VL-3 or contains VH-3.

[0206] In certain embodiments, the multispecific antibody may be any of the above-described multispecific antibodies, including ABR-1, ABR-2, ABR-3, and ABR-4, (XXII)(A) Antigen A is the fourth antigen, VH-A is VH-4 or contains it, and / or VL-A (if present) is VL-4 or contains it, and (B) Antigen B is the second antigen, VH-B is VH-2 or contains it. (C) Antigen C is a third antigen, VH-C is VH-3 or contains VH-3, and / or VL-C (if present) is VL-3 or contains VL-3, and (D) Antigen D is human CD28, VH-D is VH-1 or contains VH-1, and / or VL-D (if present) is VL-1 or contains VL-1.

[0207] In certain embodiments, the multispecific antibody may be any of the above-described multispecific antibodies, including ABR-1, ABR-2, ABR-3, and ABR-4, (XXIII)(A) Antigen A is the fourth antigen, VH-A is VH-4 or contains it, and / or VL-A (if present) is VL-4 or contains it, (B) Antigen B is the third antigen, VH-B is VH-3 or contains it (C) Antigen C is human CD28, VH-C is VH-1 or contains VH-1, and / or VL-C (if present) is VL-1 or contains VL-1, and (D) Antigen D is a second antigen, VH-D is VH-2 or contains VH-2, and / or VL-D (if present) is VL-2 or contains VL-2.

[0208] In certain embodiments, the multispecific antibody may be any of the above-described multispecific antibodies, including ABR-1, ABR-2, ABR-3, and ABR-4, (XXIV)(A) Antigen A is the fourth antigen, VH-A is VH-4 or contains it, and / or VL-A (if present) is VL-4 or contains it, and (B) Antigen B is the third antigen, VH-B is VH-3 or contains it. (C) Antigen C is a secondary antigen, VH-C is VH-2 or contains VH-2, and / or VL-C (if present) is VL-2 or contains VL-2, and (D) Antigen D is human CD28, VH-D is VH-1 or contains VH-1, and / or VL-D (if present) is VL-1 or contains VL-1.

[0209] In certain embodiments, a multispecific antibody according to any of the multispecific antibodies described above may include the structure shown in any one of Figures 2C (top left), 2F, 2G (in the box), 2J (in the box), 2K (in the box), 2J, and / or 2M, wherein antigen A and antigen B are CD28 and CD3, or CD3 and CD28, respectively.

[0210] In a particular embodiment, a multispecific antibody according to any of the multispecific antibodies described above may include a structure shown in any one of Figures 3A to 3B, which optionally includes: (a) antigen A and antigen B are CD28 and CD3, or CD3 and CD28, respectively; (b) antigen A and antigen C are CD28 and CD3, or CD3 and CD28, respectively; or (c) antigen B and antigen C are CD28 and CD3, or CD3 and CD28, respectively.

[0211] In a particular embodiment, a multispecific antibody according to any of the multispecific antibodies described above may include the structure shown in any one of Figures 4A-4C, 5A (in the box), 5C-5F, 5H (top left), 5I (top left), and / or 5J-5M, and optionally (a) antigen A and antigen B are CD28 and CD3, or CD3 and CD28, respectively; (b) antigen A and antigen C are CD28 and CD3, or CD3 and CD28, respectively; (c) antigen A and antigen D are CD28 and CD3, or CD3 and CD28, respectively; (d) antigen B and antigen C are CD28 and CD3, or CD3 and CD28, respectively; (e) antigen B and antigen D are CD28 and CD3, or CD3 and CD28, respectively; or (f) antigen C and antigen D are CD28 and CD3, or CD3 and CD28, respectively.

[0212] In certain embodiments, a multispecific antibody according to any of the multispecific antibodies described above may be conjugated monovalently, bivalently, trivalently, or tetravalently to (a) human differentiation cluster 3 (CD3), (b) cancer antigen, optionally TSA or TAA, (c) human CD28, (d) any one antigen selected from those listed in Table 3, and / or (e) any one cancer antigen selected from those listed in Table 3, optionally one TSA or one TAA.

[0213] In a particular embodiment, a multispecific antibody according to any of the above-described multispecific antibodies may be bivalently bound to CD3.

[0214] In one embodiment, the present disclosure provides nucleic acids (e.g., encoding nucleic acids, or sets of encoding combined nucleic acids) encoding any of the anti-human CD28 antibodies or antigen-binding antibody fragments described herein, or any of the multispecific antibodies described herein or a portion thereof.

[0215] In some embodiments, the nucleic acids may include VH-1 coding nucleic acids having at least about 80%, at least about 85%, at least about 90%, at least about 91%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, at least about 99%, or 100% identity with any one of the VH coding sequences in Table 2A and / or 13A, and VL-1 coding nucleic acids having at least about 80%, at least about 85%, at least about 90%, at least about 91%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, at least about 99%, or 100% identity with any one of the VL coding sequences in Table 2A and / or 13A.

[0216] In a particular embodiment, nucleic acids have at least about 80%, at least about 85%, at least about 90%, at least about 91%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, at least about 99%, or 100% identity with the VH coding sequence of SEQ ID NOs. 119, 2119, 2819, 4619, 5719, 6119, 6819, 7019, or 8319. It may also contain a VL-1 coding nucleic acid having at least about 80%, at least about 85%, at least about 90%, at least about 91%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, at least about 99%, or 100% identity with the 1 coding nucleic acid and / or the VL coding sequence of sequence numbers 129, 2129, 2829, 4629, 5729, 6129, or 6829.

[0217] In a particular embodiment, the nucleic acids may include VH-1 coding nucleic acids and VL-1 coding nucleic acids having at least about 80%, at least about 85%, at least about 90%, at least about 91%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, at least about 99%, or 100% identity with SEQ ID NOs: 119 and 129, 2119 and 2129, 2819 and 2829, 4619 and 4629, 5719 and 5729, 6119 and 6129, or 6819 and 6829, respectively.

[0218] In certain embodiments, the nucleic acids may include VH-1 coding nucleic acids and VL-1 coding nucleic acids having at least about 80%, at least about 85%, at least about 90%, at least about 91%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, at least about 99%, or 100% identity with respect to SEQ ID NOs. 119 and 129, respectively.

[0219] In certain embodiments, the encoded anti-CD28 antibody or antigen-binding antibody fragment comprising VH-1 and VL-1 may also comprise kappa VL. In certain embodiments, the nucleic acids may comprise VH-1 coding nucleic acids and VL-1 coding nucleic acids having at least about 80%, at least about 85%, at least about 90%, at least about 91%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, at least about 99%, or 100% identity with SEQ ID NOs. 2119 and 2129, or 2819 or 2829, respectively.

[0220] In certain embodiments, the encoded anti-CD28 antibody or antigen-binding antibody fragment comprising VH-1 and VL-1 may also comprise lambda VL. In certain embodiments, the nucleic acids may comprise VH-1 coding nucleic acids and VL-1 coding nucleic acids having at least about 80%, at least about 85%, at least about 90%, at least about 91%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, at least about 99%, or 100% identity with respect to SEQ ID NOs. 4619 and 4629, and 5719 and 5729, respectively.

[0221] In certain embodiments, the encoded anti-CD28 antibody or antigen-binding antibody fragment comprising VH-1 and VL-1 may include a common VL (for example, a VL that binds to CD28 when paired with a VH having specificity for CD28, and binds to CD3 when paired with a VH having specificity for CD3). In certain embodiments, the nucleic acids may include VH-1 coding nucleic acids and VL-1 coding nucleic acids having at least about 80%, at least about 85%, at least about 90%, at least about 91%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, at least about 99%, or 100% identity with SEQ ID NOs. 6119 and 6129, or 6819 and 6829, respectively.

[0222] In certain embodiments, a VH-1-encoded anti-CD28 antibody or antigen-binding antibody fragment may be able to bind to CD28 without requiring a VL (e.g., VHH, nanobody, single-domain antibody (sdAb), heavy-chain antibody (HCAb), etc.). In certain embodiments, the nucleic acid may contain a VH-1-encoded nucleic acid having at least about 80%, at least about 85%, at least about 90%, at least about 91%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, at least about 99%, or 100% identity to SEQ ID NO: 7019 or 8319.

[0223] In one embodiment, the present disclosure provides a vector (e.g., an encoding vector or a set of encoding combined vectors) encoding any of the anti-human CD28 antibodies or antigen-binding antibody fragments described herein, or any of the multispecific antibodies described herein or a portion thereof. Such a vector may include the nucleic acids described above.

[0224] In some embodiments, the vector may be an expression vector.

[0225] In some embodiments, the vector may include plasmids, viral vectors (optionally adenoviruses, lentiviruses, or retroviruses), lipid-based vectors, self-replicating RNA vectors, virus-like particles, polymer-based vectors, and / or nanoparticles, optionally lipid-based nanoparticles.

[0226] In one embodiment, the present disclosure provides isolated, recombinant, and / or host cells comprising the nucleic acids or vectors described above.

[0227] In some embodiments, the cells may be non-mammalian, optionally bacteria, yeast, fungi, protozoa, plants, or insects, or may include bacterial cells.

[0228] In some embodiments, the cells may be (ii) mammalian, optionally human, non-human primate, monkey, rabbit, rodent, hamster, rat, or mouse cells, or may include them.

[0229] In one embodiment, the present disclosure provides a composition comprising at least one excipient, and at least one of any anti-human CD28 antibody or antigen-binding antibody fragment described herein and / or any multispecific antibody, any nucleic acid described herein, any vector described herein, and any isolation, recombination, and / or host cell described herein.

[0230] In further embodiments, the Disclosure provides a method for treating a disease, disorder, or condition in a subject. The method may include administering to the subject an effective amount of at least one of the anti-human CD28 antibody or antigen-binding antibody fragments and / or multispecific antibodies described herein, any nucleic acid described herein, any vector described herein, and any isolated, recombinant, and / or host cells described herein, and / or compositions described herein.

[0231] In some embodiments, the subjects are (i) mammals, optionally humans, non-human primates, monkeys, horses, cattle, sheep, goats, pigs, dogs, cats, rabbits, rodents, hamsters, rats, or mice, or (ii) non-mammalian vertebrates, optionally birds, fish, amphibians, or reptiles.

[0232] In some embodiments, the method may further include administering an additional drug, optionally an adjuvant, or therapeutic agent to the subject.

[0233] In some embodiments, the disease, disorder, or condition may include cancer or neoplasm, autoimmune disease, neurodegenerative disease, infectious disease, inflammatory disease, or other disease.

[0234] In certain embodiments, the cancer may be a solid cancer, or optionally selected from one or more of the following: mesothelioma, malignant pleural mesothelioma, non-small cell lung cancer, small cell lung cancer, squamous cell carcinoma of the lung, large cell lung cancer, pancreatic cancer, pancreatic ductal adenocarcinoma, esophageal adenocarcinoma, breast cancer, glioblastoma, ovarian cancer, colorectal cancer, prostate cancer, cervical cancer, skin cancer, melanoma, kidney cancer, liver cancer, brain cancer, thymoma, sarcoma, carcinoma, uterine cancer, kidney cancer, gastrointestinal cancer, urothelial carcinoma, pharyngeal cancer, head and neck cancer, rectal cancer, esophageal cancer, or bladder cancer, or metastases thereof.

[0235] In certain embodiments, cancer is humoral cancer, optionally including chronic lymphocytic leukemia (CLL), mantle cell lymphoma (MCL), multiple myeloma, acute lymphoblastic leukemia (ALL), Hodgkin lymphoma, B-cell acute lymphoblastic leukemia (BALL), T-cell acute lymphoblastic leukemia (TALL), small lymphocytic leukemia (SLL), B-cell prolymphocytic leukemia, blast-cell plasmacytoid dendritic neoplasm, and - Kitt lymphoma, diffuse large B-cell lymphoma (DLBCL), DLBCL associated with chronic inflammation, chronic myeloid leukemia, myeloproliferative disorders, follicular lymphoma, pediatric follicular lymphoma, hairy cell leukemia, small cell or large cell follicular lymphoma, malignant lymphoproliferative state, MALT lymphoma (extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue), marginal zone lymphoma, spinal dysplasia, myelodysplastic syndrome Non-Hodgkin lymphoma, plasmablastic lymphoma, plasmacytoid dendritic cell neoplasm, Waldenström's hypergammaglobulinemia, splenic marginal zone lymphoma, splenic lymphoma / leukemia, diffuse red medullary small cell B-cell lymphoma of the spleen, hairy cell leukemia variant, lymphoplasmacytic lymphoma, heavy chain disease, plasmacytomyeloma, solitary plasmacytoma of bone, extraskeletal plasmacytoma, nodular marginal zone lymphoma, pediatric nodular marginal zone lymphoma It may also be a humoral cancer selected from pediatric leukemia, primary cutaneous follicular lymphoma, lymphomatoid granulomatosis, primary mediastinal (thymic) large B-cell lymphoma, intravascular large B-cell lymphoma, ALK+ large B-cell lymphoma, large B-cell lymphoma arising from HHV8-associated multicentric Castleman disease, primary humoral lymphoma, B-cell lymphoma, acute myeloid leukemia (AML), or lymphoma that cannot be classified.

[0236] In certain embodiments, the autoimmune or inflammatory disease is psoriasis, rheumatoid arthritis, autoimmune arthritis, type 1 diabetes, systemic lupus erythematosus, myasthenia gravis, multiple sclerosis, scleroderma, inflammatory bowel disease, Crohn's disease, ulcerative colitis, Guillain-Barré syndrome, chronic inflammatory demyelinating polyneuropathy, pemphigus vulgaris, Sjögren's syndrome, Addison's disease, Behçet's disease, Schmidt's syndrome, celiac disease, dermatomyositis, autoimmune vitiligo, Graves' disease, Hashimoto's thyroiditis, Kawasaki disease, pernicious anemia, autoimmune vasculitis, or fibrosis.

[0237] In certain embodiments, neurodegenerative diseases include Alzheimer's disease, Huntington's disease, Parkinson's disease, amyotrophic lateral sclerosis, Friedreich's ataxia, Lewy body dementia, spinal muscular atrophy, motor neuron disease, multiple sclerosis, Batten disease, and Creutzfeldt-Jakob disease.

[0238] In certain embodiments, the infectious disease may be a viral disease, bacterial disease, fungal disease, yeast disease, protozoan disease, prion disease, or parasitic disease, and optionally, (1) viral diseases may include human immunodeficiency virus (HIV), hepatitis virus (optionally, hepatitis A, B, or C), human papillomavirus (HPV), herpes simplex virus (HSV) (optionally, HSV-1 or HSV-2), enterovirus, human cytomegalovirus, adenovirus, rhinovirus, poxvirus, influenza virus, coronavirus (optionally, MERS-CoV, SARS-CoV, or SARS-CoV-2, or common human coronavirus). (1) Bacterial diseases include infections of Salmonella, Escherichia coli, Mycobacterium tuberculosis, Staphylococcus aureus methicillin-resistant (MRSA), Clostridium difficile, Streptococcus pneumoniae, Klebsiella pneumoniae, Pseudomonas aeruginosa, Helicobacter pylori, Neisseria gonorrhoeae, Vibrio vulnificus, and / or (3) Fungal diseases include infections of Aspergillosis, Candida, Candida auris, Cryptococcus neoformans, Pneumocystis irovecii, Mucor, Talaromyces, Ringworm, Blastomyces, Coccidioides, Cryptococcus gattii, Histoplasma, Paracoccidioides, or Sporotrichus.

[0239] In a further embodiment, the present disclosure provides a method for producing any of the anti-human CD28 antibodies or antigen-binding antibody fragments described herein, or any of the multispecific antibodies described herein.

[0240] In some embodiments, the method may include (a) culturing cells containing any of the nucleic acids described herein under conditions that enable the expression of the antibody or antigen-binding antibody fragment or the multispecific antibody, and (b) collecting and purifying the antibody or antigen-binding antibody fragment from the cell culture from (a).

[0241] In a further embodiment, the present disclosure provides a method for producing any of the isolated, recombinant, and / or host cells described herein, or a population of such cells.

[0242] In some embodiments, the method may include introducing one or more cells with any of the nucleic acids and / or vectors described herein, and optionally, the introduction may occur in vitro, ex vivo, or in vivo.

[0243] Any anti-human CD28 antibody or antigen-binding antibody fragment according to this disclosure, or any multispecific antibody according to this disclosure, any nucleic acid according to this disclosure, any vector according to this disclosure, any isolation, recombination, and / or host cell or population of such cells according to this disclosure, or any composition according to this disclosure may be for use in pharmaceutical use or for use in the preparation of pharmaceuticals for use in pharmaceutical use.

[0244] Any anti-human CD28 antibody or antigen-binding antibody fragment in accordance with this disclosure, or any multispecific antibody in accordance with this disclosure, any nucleic acid in accordance with this disclosure, any vector in accordance with this disclosure, any isolation, recombination, or host cell or population of such cells in accordance with this disclosure, or any composition in accordance with this disclosure may be for use in the treatment of a disease, disorder, or condition, and optionally, the disease, disorder, or condition includes one or more of those described herein.

[0245] Any anti-human CD28 antibody or antigen-binding antibody fragment in accordance with this disclosure, or any multispecific antibody in accordance with this disclosure, any nucleic acid in accordance with this disclosure, any vector in accordance with this disclosure, any isolation, recombination, or host cell or population of such cells in accordance with this disclosure, or any composition in accordance with this disclosure may be for use in the manufacture of a pharmaceutical for the treatment of a disease, disorder, or condition, and optionally, the disease, disorder, or condition comprises one or more of those described herein. [Brief explanation of the drawing]

[0246] Figures 1-6 provide exemplary and non-limiting embodiments of the structures of various antibodies, antigen-binding antibody fragments, and multispecific antibodies, which may include any of the anti-CD28 antibody sequences disclosed herein. In Figures 1-6, unless otherwise indicated, the following rules apply. (1) Each domain is represented as a rectangle containing text indicating a domain name (e.g., CH3, VH, etc.), (2) A set of multiple domains connected to each other represents a polypeptide (e.g., heavy chain polypeptide, light chain polypeptide, etc.), (3) The orientation of domains within a polypeptide follows the direction of the text indicating the domain name, from the N-terminus to the C-terminus, (4) Linkers or hinges may be used between domains as necessary, and disulfide bonds may be present between polypeptides (and / or within domains or polypeptides) to enable the correct formation of antigen-binding sites, even if the drawing does not explicitly show linkers, hinges, or disulfide bonds, (5) Any of the constant domains shown in the drawing (e.g., CH1, CH2, and / or CH3 domains) may be omitted or replaced with another constant domain if possible and / or desirable, and may be replaced with a hinge or linker if appropriate, (6) Pattern (i.e., the outlined rectangles) are domains that may each contain a corresponding wild-type sequence or one or more amino acid substitutions relative to the wild-type sequence, (7) the hinges and CH1, CH2, and CH3 domains may each be of any (heavy chain) isotype, (8) if two or more hinges are present in the structure, the hinges may or may not be of the same isotype; if two or more CH1 domains are present in the structure, the CH1 domains may or may not be of the same isotype; if two or more CH2 domains are present in the structure, the CH2 domains may or may not be of the same isotype; if two or more CH3 domains are present in the structure, the CH3 domains may or may not be of the same isotype, (9) the light chain constant (CL) domains may be kappa CL domains or lambda CL domains, (10) if two or more CL domains are present in the structure, all CL domains are(11) If both kappa and lambda CL domains are present, the CH1 domains paired with the CL domains may, in some cases, be variant CH1 domains, one of which may be a variant CH1 that preferentially binds to kappa CLs, and another CH1 domain may be a variant CH1 that preferentially binds to lambda CLs (for example, if the molecule contains kappa CL (12) The presence of lambda CL, as well as kappa-preferred CH1 and lambda-preferred CH1, potentially enables efficient manufacturing. (13) In a given VH-VL pair, if VH alone provides sufficient specificity to a congener antigen (e.g., a nanobody), VL may be omitted even if it is shown in the drawing. (14) If two or more antigen-binding sites are present, all antigen-binding sites may bind to the same epitope, or at least one or more antigen-binding sites may bind to different epitopes.

[0247] [Figure 1A-J](i) various anti-CD28 antibodies and antigen-binding antibody fragments, and / or (ii) various antigen-binding regions (ABRs) that may be included in multispecific antibodies according to this disclosure, or some exemplary and non-limiting embodiments of such structures are provided. Figure 1A provides some basic and exemplary antibody structures. The antibody in the upper left (in the box) is an exemplary, standard full-size antibody in which hinges or disulfide bonds are not explicitly shown. The antibody in the box may, for example, include a hinge between CH1 and CH2, and one or more disulfide bonds (dashed lines) may be present between the hinges and / or between CH1 and CL (center). Alternatively, the antibody in the box may, for example, include a hinge between CH1 and CH2, and one or more disulfide bonds (dashed lines) may be present between the hinges and / or between CL and the hinge (right). Hinge and disulfide bonds, including but not limited to those shown in the central and right antibody structures, may be present in any of the structures shown in the drawings and described herein, even if not explicitly shown. Figure 1B provides some variations of the boxed antibody structure and its description provided in Figure 1A. In some variants of the boxed antibody in Figure 1A, the positions of VH and VL are swapped, and / or the positions of CH1 and CL are swapped, compared to the boxed structure in Figure 1A. Variations equivalent to those shown in Figure 1B (swapping of VH-VL and / or CH1-CL positions) may, where appropriate, be further applied to any of the structures shown in Figures 1-6 and their descriptions, or their variations, even if not explicitly shown. Figure 1C provides some variations of the boxed antibody structure and its description provided in Figure 1A. In some variants of the boxed antibody in Figure 1A, any of the constant domains may be omitted, where possible and / or desirable, even if shown in the drawings. For example, the CH3 domain may be omitted (top column), the CH2 domain may be omitted (middle column), and / or the CH1 and CL domains may be omitted (bottom column).Even when such constant domains can be omitted, hinges and / or disulfide bonds may be present (e.g., in the middle and right structures of each column), or linkers may be present to connect the domains (e.g., an exemplary and optional linker shown by a dashed square in the left structure of the third bottom column). Variations equivalent to those shown in Figure 1C (omitting one or more CH3, CH2, CH1, and / or CL domains) may, where appropriate, be further applied to any of the structures shown in Figures 1-6 and their descriptions, or their variations, even if not explicitly shown. Figure 1D provides some variations of the antibody box structure and its description provided in Figure 1A. In some variants of the antibody box in Figure 1A, two or more of the constant domains may be omitted where possible and / or desirable, even if shown in the drawing. For example, the CH1, CL, and CH2 domains may be omitted (top column), the CD1, CL, and CH3 domains may be omitted (second column), the CH2 and CH3 domains may be omitted (third column), and / or the CH1, CH2, and CH3 domains may be omitted (bottom column). Even when such constant domains can be omitted, hinges and / or disulfide bonds may be present (e.g., the middle and right structures in each column). The middle and right structures in the third column may be referred to as F(ab')2. Variations equivalent to those shown in Figure 1D (omitting two or more of the CH3, CH2, CH1, and / or CL domains) may, where appropriate, be further applied to any of the structures shown in Figures 1-6 and their descriptions, or their variations, even if not explicitly shown. Figure 1E provides additional variations of antibody structures. This disclosure further encompasses “half-antibody” variants of any of the antibodies provided in Figures 1A-1D or their descriptions. The structure in the upper left (inside the box) is a "half-antibody" variant of the antibody structure in the box provided in Figure 1A. In some variants of the "half-antibody" in the box, the positions of VH and VL are swapped, and / or the positions of CH1 and CL are swapped, compared to the structure in the box in Figure 1A.In some variants of the "half-antibody" in the box, the CH3 domain may be omitted (center left), the CH2 domain may be omitted (center column, second from the left), the CH1 and CL domains may be omitted (center of the center column), the CH1, CH2, and CL domains may be omitted (center column, second from the right), or the CH1, CH3, and CL domains may be omitted (center column, right). In some variants of the "half-antibody domain" in the box, the CH2 and CH3 domains may be omitted (bottom left (inside the box), which may be called the fragment antigen-binding region (Fab)), or the CH2 and CH3 domains may be omitted, and there is a hinge or portion thereof of sufficient length to provide cysteine ​​for disulfide bonding (bottom, second from the left, which may be called Fab'). Variants of the Fab structure may include those in which the positions of CH1 and CL are swapped (bottom, second from the right). In some variants of the “half-antibody” in the box, the CH1, CH2, CH3, and CL domains may be omitted (bottom right), and this may be referred to as a variable fragment (Fv). Variations equivalent to those shown in Figure 1E (“half-antibody” variants, i.e., structures containing the monomer portion of a dimer (or the dimer portion of a tetramer, etc.) contained in the parent structure) may, where appropriate, be further applied to any of the structures shown in Figures 1-6 and their descriptions, or their variations, even if not explicitly shown. Figure 1F provides further variations of the antibody structure in the box and its description provided in Figure 1A. In some variants of the antibody in the box in Figure 1A, VH and VL may be arranged in series within the polypeptide in the direction from the N-terminus to the C-terminus or from the C-terminus to the N-terminus, with or without a linker between VH and VL (top row, left, and right, respectively). Such structures may be referred to as single-stranded fragment variable regions (scFv). In further variants, two or more of these scFvs may be arranged in series within the polypeptide (in the middle column). Such a structure may be called a tandem scFv. Variants containing multiple scFvs may also include diabodies, triabodies, and tetrabodies (left, center, and right below, respectively).Each is shown using an in-box scFv structure, although, for example, the positions of VH-VL may be swapped). Figure 1G provides further variations of the in-box antibody structure provided in Figure 1A or the in-box scFv and their descriptions in Figure 1F. Some structures may include scFv instead of the VH-VL set of the in-box antibody structure provided in Figure 1A, or the scFv may be located at the N-terminus of CH1 (e.g., top left), the N-terminus of CL (e.g., bottom left), the C-terminus of CL (e.g., bottom center), or the C-terminus of CH3 (e.g., bottom right), or a combination thereof. Structures containing two scFv are shown, but some structures may contain one scFv, two scFv (e.g., top left (in-box) and bottom), three scFv, four scFv, or more scFv (e.g., five, six, seven, or eight scFv). As described above, one or more of the constant domains may be omitted. For example, the CH1 and CL domains may be omitted (the structure may be referred to as scFv-Fc), or either the CH2 or CH3 domain may be further omitted (the structure may be referred to as scFv-CH). Any such structure in which an scFv is directly or indirectly (e.g., via a hinge) linked to a CH domain paired with another CH domain may be referred to as scFv-CH. Furthermore, as described above, any of the structures in Figure 1G and the “half-antibody” variants described therein are further encompassed by this disclosure. Some structures may include two scFvs, each attached to the N-terminus or C-terminus of a dimeric polypeptide forming a leucine zipper (top row, middle, and right, respectively). Such structures may be referred to as scFv-zippers. Figure 1G shows a structure using the scFv in the box in Figure 1F, but structures using any scFv or scFv variant, such as those in Figure 1F, but not limited to those, are also included in this disclosure (e.g., diabody-Fc and diabody-CH, where the scFv in scFv-Fc and scFv-CH are replaced by diabodies, respectively). Figure 1H provides further variations of the antibody structure in the box provided in Figure 1A or the scFv in the box in Figure 1F and their descriptions.In some variants of the antibody in the box in Figure 1A, VH followed by a constant domain (e.g., CH1) and VL followed by a constant domain (e.g., CL) may be arranged in series within the polypeptide with or without a linker between VH followed by a constant domain and VL followed by a constant domain, either from the N-terminus to the C-terminus (top row, left (in the box) and second from the left) or from the C-terminus to the N-terminus (top row, third and fourth from the left). Such structures may be referred to as single-stranded Fabs (scFabs). In further variants, any two or more of these scFabs may be arranged in series within the polypeptide with or without a linker (e.g., top right). Such structures may be referred to as tandem scFabs. Variants containing multiple scFabs may also include structures in the bottom row, each of which is shown using the scFab structure in the box, but the positions of VH-VL and / or CH1-CL may be swapped, for example. Figure 1I provides further variations of the box-in-box antibody structure provided in Figure 1A or the box-in-box scFab and their descriptions in Figure 1H. Some structures may include scFab instead of the VH-VL set of box-in-box antibody structures provided in Figure 1A, or the scFab may be located at the N-terminus of CH1 (e.g., top left (in the box)), the N-terminus of CL (e.g., bottom left), the C-terminus of CL (e.g., bottom center), or the C-terminus of CH3 (e.g., bottom right), or a combination thereof. Structures containing two scFab are shown, but some structures may contain one scFab, two scFabs (e.g., top left (in the box) and bottom), three scFabs, four scFabs, or more scFabs (e.g., five, six, seven, or eight scFabs). As described above, one or more of the constant domains may be omitted. For example, the CH1 and CL domains (present in the parent structure, i.e., the structure in the box in Figure 1A) may be omitted (the structure may be referred to as scFab-Fc), or either the CH2 or CH3 domain may be further omitted (the structure may be referred to as scFab-CH). Furthermore, as mentioned above, any of the structures in Figure 1I and their descriptions, as well as the "half-antibody" variants, are also included.Some structures may include two scFabs, each attached to the N-terminus or C-terminus of a dimeric polypeptide forming a leucine zipper (top row, center, and right, respectively). Such structures may be referred to as scFab-zippers. Figure 1I shows structures using the scFab in the box in Figure 1H, but this disclosure also includes, and is not limited to, structures using other scFabs and their variants. Figure 1J provides further variations of the antibody structures in the box provided in Figure 1A, or the structures and their descriptions provided in any of Figures 1A-1I. As stated above, the VL may be omitted as long as the VH alone provides sufficient specificity to the congener antigen. Therefore, this disclosure includes structures that are the same as any of the structures included in Figures 1A-1I or their descriptions, except that at least one VL (and optionally one or more CL domains) is omitted. For example, some structures may contain only VH that is not paired with VL (e.g., top left, which may be called a single-domain antibody (sdAb) or nanobody). In some structures, any two or more such sdAbs may be arranged in series within the polypeptide with or without a linker (e.g., top right), which may be called a tandem sdAb or tandem nanobody. Some structures may contain sdAbs instead of the VH-VL set of antibody structures in the box provided in Figure 1A. In some structures, the sdAb may be located at the N-terminus of CH1 (e.g., center left). In some cases, one or more of the CL domains may be further omitted (e.g., middle column, second from the left), and in some cases, the CH1 domain may be further omitted, and the structure may be called a camel or camelid antibody (a hinge is typically present). In some cases, sdAb may be located at the N-terminus of CL (e.g., bottom left), the C-terminus of CL (e.g., bottom center), or the C-terminus of CH3 (e.g., top row, second from the right; or one or more of the CL domains may be further omitted (e.g., top right)), or a combination thereof.While structures containing two scFvs are shown, some structures may contain one, two, three, four, or more sdAbs (e.g., five, six, seven, or eight sdAbs). As described above, one or more of the constant domains may be omitted. For example, the CH1 and CL domains may be omitted (the structure may be referred to as sdAb-Fc), or either the CH2 or CH3 domain may be further omitted (the structure may be referred to as sdAb-CH). Any of these structures may further contain one or more additional constant domains. The structure in the lower right may be referred to as an immunoglobulin neoantigen receptor (IgNAR), and variants thereof that do not contain the CH4 or CH5 domain are also included in this disclosure. Furthermore, as described above, any of the structures in Figure 1J and the “half-antibody” variants described therein are also included. Any structure that does not contain VL or CL may be referred to as a heavy-chain-only antibody (HCAb). Figures 2 to 6 provide schematic diagrams of structures that may be composed of or contained in antibodies containing two or more antigen-binding regions (ABRs), such as multispecific antibodies according to this disclosure, and some exemplary and non-limiting embodiments. In addition to rules (1) to (14) above, the following rules apply unless otherwise indicated.(15) VH-A and VL-A form antigen-binding sites specific to antigen A or epitope A; VH-B and VL-B form antigen-binding sites for antigen B or epitope B; VH-C and VL-C form antigen-binding sites for antigen C or epitope C; VH-D and VL-D form antigen-binding sites for antigen D or epitope D; VH-E and VL-E form antigen-binding sites for antigen E or epitope E; VH-F and VL-F form antigen-binding sites for antigen F or epitope F forms an antigen-binding site, VH-G and VL-G form an antigen-binding site for antigen G or epitope G, VH-H and VL-H form an antigen-binding site for antigen H or epitope H, VH-I and VL-I form an antigen-binding site for antigen I or epitope I, and VH-J and VL-J form an antigen-binding site for antigen J or epitope J, (16) all of antigens A to J or epitopes A to J may be different from each other, or antigens A to J or (17) If all of epitopes A to J are not different from each other, the paired striped and dashed constant domains in the diagram (e.g., a set of CH1 and CL domains, or a set of two CH3 domains) may or may not be a set of constant domains, and one or both of them are manipulated to promote preferential pairing between the constant domains of the set (e.g., pairing with another constant domain), (18) Two or more VL domains in a dashed grid in the structure may or may not be common VLs (i.e., VLs having the same amino acid sequence), and two or more VL domains in a solid grid in the structure may or may not be common VLs, (19) If both VL domains in a dashed grid and VL domains in a solid grid are present, the VL domains in a dashed grid and VL domains in a solid grid may or may not have the same amino acid sequence. [Figure 2A]This document provides schematic diagrams of antigen-binding structures ("AB-A / B") that bind to antigens A and B and / or epitopes A and B, which may be included in antibodies, antigen-binding antibody fragments, and multispecific antibodies (e.g., bispecific antibodies). Such an AB-A / B comprises (1) an antigen-binding structure (AB-A) containing at least one antigen-binding region (ABR-A) that binds to antigen A or epitope A, and (2) at least one antigen-binding region (ABR-B) that binds to antigen B or epitope B. Antigens A and B may be the same or different from each other, and epitopes A and B may be the same or different from each other. Eight ABR-Bs are shown, but the structure may contain one or any number of ABR-Bs, for example, one, two, three, four, or more (e.g., five, six, seven, or eight). In some cases, AB-A and / or ABR-A may include one or more of the structures in Figures 1A-1J or descriptions thereof. In some cases, ABR-B may include one or more of the structures in Figures 1A-1J or descriptions thereof. AB-A and ABR-B may optionally associate with each other via one or more disulfide bonds, or optionally link with each other in any suitable manner via hinges or linkers. For example, the N-terminus or C-terminus of a polypeptide contained in ABR-B may be linked to the N-terminus or C-terminus of a polypeptide contained in AB-A. [Figure 2B-E](1) ABR-A having the structure of a full-size antibody that binds to antigen A or epitope A, comprising (a) a polypeptide (which may be called heavy chain A) comprising a heavy chain variable domain A (VH-A) and a heavy chain constant domain A (CH-A) (CH-A may include heavy chain constant domain 1A (CH1-A), hinge (Hinge-A), heavy chain constant domain 2A (CH2-A), and / or heavy chain constant domain 3A (CH3-A)) from the N-terminus to the C-terminus, and (b) a polypeptide (which may be called light chain A) comprising a light chain variable domain A (VL-A) and a light chain constant domain A (CL-A) from the N-terminus to the C-terminus, wherein heavy chain A and light chain A are optionally paired with each other via at least one disulfide bond, ABR-A (e.g., structure in the box in Figure 1A), and (2 )Providing an exemplary AB-A / B structure (as encompassed by the structure in Figure 2A and its description) comprising: (a) a polypeptide (which may be called heavy chain B) comprising a heavy chain variable domain B (VH-B) and a heavy chain constant domain B (CH-B) (CH-B may include at least a heavy chain constant domain 1B (CH1-B)) from the N-terminus to the C-terminus; and (b) a polypeptide (which may be called light chain B) comprising a light chain variable domain B (VL-B) and a light chain constant domain B (CL-B) from the N-terminus to the C-terminus, wherein heavy chain B and light chain B are optionally paired with each other via at least one disulfide bond; and an ABR-B (e.g., the Fab structure in the box in Figure 1E). In Figures 2B-2E, both the heavy chain B and light chain B of at least one Fab-B are linked to heavy chain A and light chain A, or light chain A and heavy chain A, respectively, of AB-A. Figure 2B shows an exemplary structure containing one Fab-B. The C-terminus of heavy chain B is attached to the N-terminus of heavy chain A, and the C-terminus of light chain B is attached to the N-terminus of light chain A paired with heavy chain A (top left), the C-terminus of light chain B is attached to the N-terminus of heavy chain A, and the C-terminus of heavy chain B is attached to the N-terminus of light chain A paired with heavy chain A (top right), or the N-terminus of heavy chain B is attached to the C-terminus of one heavy chain A, and the N-terminus of light chain B is attached to the C-terminus of another heavy chain A (bottom).Figure 2C shows additional exemplary structures containing two Fab-Bs. In some structures, one Fab-B is attached to the N-terminus of one heavy-chain and light-chain A pair, and the other Fab-B is attached to the N-terminus of the other heavy-chain and light-chain A pair (the three structures on the left). In some structures, two Fab-Bs are attached in series to the C-terminuses of two heavy-chain As (the structures in the center and on the right). Figure 2D shows additional exemplary structures containing two Fab-Bs. In some structures, two Fab-Bs are attached in series to the C-terminus of one heavy-chain and light-chain A pair. Figure 2E shows additional exemplary structures containing two Fab-Bs. In some structures, one Fab-B is attached to the N-terminus of one heavy-chain and light-chain A pair, and the other Fab-B is attached to the C-terminuses of two heavy-chain As. In Figures 2B–2E, the structures include one full-size antibody and one or two Fabs are shown, but structures including any number of Fabs (e.g., three, four, five, six, seven, eight, or more) are also covered by this disclosure. Furthermore, in Figures 2B–2E, structures using the full-size antibody structure in the box in Figure 1A and the Fab structure in the box in Figure 1E are shown, but structures using other full-size antibody structures and their variants, including but not limited to those in Figures 1A–1E and their descriptions (e.g., with one or more domains omitted, with domain positions swapped, and / or half-antibody variants), and / or those in Figure 1E and their descriptions (e.g., with one or more domains omitted (e.g., Fv when both CH-B and CL-B are omitted), with domain positions swapped, and / or hinged (Fab')), are also covered by this disclosure. [Figure 2F]We provide schematic diagrams of antibodies, antigen-binding antibody fragments, and multispecific antibodies (as encompassed by the structure and description in Figure 2A), which include (1) at least one ABR-A having the structure of a full-size antibody that binds to antigen A or epitope A, and comprising (a) a polypeptide (which may be called heavy chain A) from the N-terminus to the C-terminus, comprising VH-A and CH-A (wherein CH-A may include CH1-A, hinge-A, CH2-A, and / or CH3-A), and (b) a polypeptide (which may be called light chain A) from the N-terminus to the C-terminus, comprising VL-A and CL-A, and the heavy chain A and light chain A are optionally paired with each other via at least one disulfide bond, comprising at least one ABR-A comprising AB-A (e.g., the structure in the box in Figure 1A), and (2) one or more ABR-Bs. Each of the one or more ABR-Bs comprises (i) Fab-B as described above in relation to Figures 2B-2E, (ii) Fv(Fv-B) that binds to antigen B or epitope B (e.g., the structure in the lower right of Figure 1E), (iii) (a) from the N-terminus to the C-terminus, (a) VH-B, (b) an optional linker, and (c) V The structure may include (iv) an scFv (scFv-B) (for example, the structure in the box in Figure 1F) that contains L-B and binds to antigen B or epitope B, (a) an scFab (scFab-B) (for example, the structure in the box in Figure 1H) (for example, the structure in the box in Figure 1H) that binds to antigen B or epitope B, with (a) VH-B, (b) CH-B (CH-B may contain at least CH1-B), (c) an optional linker, (d) VL-B, and (e) CL-B from the N-terminus to the C-terminus, or (v) an sdAb (sdAb-B) that contains VH-B and binds to antigen B or epitope B. In the case of (a) and (b) (i.e., Fab-B and Fv-B), either the heavy chain B or the light chain B is linked to the heavy chain A or light chain A of AB-A.In the case of (c)~(e) (i.e., scFv-B, scFab-B, and sdAb-B), the N-terminus or C-terminus of ABR-B is ligated to the heavy chain A or light chain A of AB-A. Furthermore, (1) structures using ABR-A having other full-size antibody structures or variants thereof, including but not limited to those in Figures 1A~1E and their descriptions (e.g., those with one or more domains omitted, those with swapped domain positions, and / or half-antibody variants), and / or (2) (a) structures in Figure 1E and their descriptions (e.g., those with one or more domains omitted, those with swapped domain positions, and / or those with hinges (Fab')), including but not limited to those, (b) other Fv structures or variants thereof, (c) structures in Figures 1F and 1G and their descriptions (e.g., those with one or more domains added, those with one or more domains omitted) (d) Other scFab structures or variants thereof, including, but not limited to, those shown in Figures 1H and 1I and their descriptions (e.g., those with one or more domains added, those with one or more domains omitted, and / or those with the domain positions swapped), or (e) Structures using ABR-B having sdAb structures or variants thereof, including, but not limited to, those shown in Figure 1J and its description (e.g., those with one or more domains added, those with one or more domains omitted, and / or those with the domain positions swapped), are further encompassed by this disclosure. Furthermore, although eight ABR-Bs are shown, a structure may include one or any number of ABR-Bs, for example, one, two, three, four, or more (e.g., five, six, seven, or eight). If two or more ABR-Bs exist, the structures of all ABR-Bs may be the same (e.g., all scFv), or one or more of the ABR-Bs may have different structures (e.g., scFv and Fab). [Figure 2G-I](1) ABR-A having the structure of a half-antibody variant of a full-size antibody (e.g., any of the full-size antibodies in Figures 1A-1B) that binds to antigen A or epitope A, wherein the half-antibody variant comprises (a) a polypeptide containing VH-A (which may optionally be called heavy chain A) and (b) a polypeptide containing VL-A (which may optionally be called light chain A), and the heavy chain A and light chain A are optionally paired with each other via at least one disulfide bond, and (2) a complete antibody that binds to antigen B or epitope B The present invention provides an exemplary structure (as encompassed by the structure in Figure 2A and its description) comprising ABR-B having the structure of a half-antibody variant of a full-size antibody (for example, any of the full-size antibodies in Figures 1A-1B), wherein the half-antibody variant comprises (a) a polypeptide containing VH-B (which may optionally be called heavy chain B) and (b) a polypeptide containing VL-B (which may optionally be called light chain B), and ABR-A and ABR-B are optionally paired with each other via at least one disulfide bond.In Figure 2G, the upper structure (in the box) is (1) ABR-A having the structure of a semi-antibody (semi-antibody A) shown in the upper left structure (in the box) of Figure 1E, which binds to antigen A or epitope A, wherein semi-antibody A comprises (a) a polypeptide (which may be called heavy chain A) from the N-terminus to the C-terminus, containing VH-A and CH-A (CH-A may also contain CH1-A, hinge-A, CH2-A, and / or CH3-A), and (b) a polypeptide (which may be called light chain A) containing VL-A and CL-A, wherein heavy chain A and light chain A are optionally paired with each other via at least one disulfide bond, and (2) ABR-A that binds to antigen B or epitope B ABR-B having the structure of a semi-antibody (semi-antibody B) shown in the upper left (inside the box) of Figure 1E, wherein semi-antibody B comprises (a) a polypeptide (which may be called heavy chain B) from the N-terminus to the C-terminus, containing VH-B and CH-B (CH-B may also contain CH1-B, hinge-B, CH2-B, and / or CH3-B), and (b) a polypeptide (which may be called light chain B) containing VL-B and CL-B, with heavy chain B and light chain B being optionally paired with each other via at least one disulfide bond, and ABR-A and ABR-B being optionally paired with each other via at least one disulfide bond. In the three structures below, one or more of the paired VH-VL positions are swapped compared to the structure in the box. In Figure 2H, in the top three structures, one or more of the positions of the paired CH1-CLs are swapped with those of the structure in the box in Figure 2G. In the bottom three structures, one or more of the positions of the paired CH1-CLs are swapped with those of the structure in the lower left of Figure 2G. In Figure 2I, in the top three structures, one or more of the positions of the paired CH1-CLs are swapped with those of the structure in the lower center of Figure 2G. In the bottom three structures, one or more of the positions of the paired CH1-CLs are swapped with those of the structure in the lower right of Figure 2G.Furthermore, relating to Figures 2G to 2I, the present disclosure further encompasses (1) structures using ABR-A having other semi-antibody structures or variants thereof, including but not limited to those shown in Figure 1E and their descriptions (e.g., with one or more domains omitted, with domain positions swapped, and / or with one or more domains added), and / or (2) structures using ABR-B having other semi-antibody structures or variants thereof, including but not limited to those shown in Figure 1E and their descriptions (e.g., with one or more domains omitted, with domain positions swapped, and / or with one or more domains added). [Figure 2J-K]The present invention provides exemplary structures (as encompassed by the structures in Figure 2A and their description) comprising: (1) ABR-A having the structure of a semi-antibody variant of one of the structures in Figures 1G and 1I and their descriptions, which binds to antigen A or epitope A; and (2) ABR-B having the structure of a semi-antibody variant of one of the structures in Figures 1G and 1I and their descriptions, which binds to antigen B or epitope B, wherein ABR-A and ABR-B are optionally paired with each other via at least one disulfide bond. In Figure 2J, the upper structure (in the box) is an ABR-A having the structure of a semi-antibody variant of the upper left structure in Figure 1G that binds to antigen A or epitope A, wherein the semi-antibody variant comprises (a) a polypeptide containing scFv-A and CH-A (CH-A may include CH1-A, hinge-A, CH2-A, and / or CH3-A) (this may optionally be called heavy chain A), and optionally (b) a polypeptide containing CL-A (this may optionally be called light chain A), and if present, heavy chain A and light chain A optionally face each other via at least one disulfide bond. ABR-B comprising (2) a half-antibody variant structure of the upper left structure in Figure 1G that binds to antigen B or epitope B, and (a) a polypeptide comprising scFv-B and CH-B (CH-B may include CH1-B, hinge-B, CH2-B, and / or CH3-B) (this may optionally be called heavy chain B), and optionally (b) a polypeptide comprising CL-B (this may optionally be called light chain B), wherein, if present, heavy chain B and light chain B are optionally paired with each other via at least one disulfide bond. Variants of some of the structures in the box are also shown (above, outside the box) in which one or more of the paired VH-VL positions are swapped compared to the structure in the box. Alternatively, ABR-A and / or ABR-B may individually contain any of the half-antibody variants from the structures in Figure 1G, instead of the half-antibody variant in the upper left structure of Figure 1G. Some of these variants include, but are not limited to, the four structures shown below.In Figure 2K, the upper structure (in the box) is an ABR-A having the structure of a semi-antibody variant of the upper left structure in Figure 1I that binds to antigen A or epitope A, wherein the semi-antibody variant comprises (a) a polypeptide containing scFab-A and CH-A (CH-A may include CH1-A, hinge-A, CH2-A, and / or CH3-A) (this may optionally be called heavy chain A), and optionally (b) a polypeptide containing CL-A (this may optionally be called light chain A), and if present, heavy chain A and light chain A optionally face each other via at least one disulfide bond. ABR-B comprising (2) a half-antibody variant structure of the structure in the upper left of Figure 1I that binds to antigen B or epitope B, and (a) a polypeptide comprising scFab-B and CH-B (CH-B may include CH1-B, hinge-B, CH2-B, and / or CH3-B) (this may optionally be called heavy chain B), and optionally (b) a polypeptide comprising CL-B (this may optionally be called light chain B), wherein, if present, heavy chain B and light chain B are optionally paired with each other via at least one disulfide bond. Variants of some of the structures in the box are also shown (above, outside the box) in which one or more of the paired VH-VL positions are swapped compared to the structure in the box. Alternatively, ABR-A and / or ABR-B may individually contain any of the half-antibody variants from the structures in Figure 1I, instead of the half-antibody variant in the upper left structure of Figure 1I. Some such variants include, but are not limited to, the three structures shown below.Further, in connection with FIGS. 2J-2K, (1) a structure using ABR-A having another half-antibody structure or a variant thereof, such as those in FIGS. 1G and 1I and their descriptions (e.g., those with one or more domains omitted, those with domain positions exchanged, and / or those with one or more domains added), but not limited thereto, and / or (2) a structure using ABR-B having another half-antibody structure or a variant thereof, such as those in FIGS. 1G and 1I and their descriptions (e.g., those with one or more domains omitted, those with domain positions exchanged, and / or those with one or more domains added), but not limited thereto, are further encompassed by the present disclosure. [Figure 2L-M]Additional exemplary structures, including structurally asymmetric formats (as encompassed by the structure and its description in Figure 2A), are provided. In Figure 2L, the upper left structure includes (1) ABR-A having the structure of a semi-antibody variant of the upper left structure in Figure 1G, which binds to antigen A or epitope A, and (2) ABR-B having the structure of a semi-antibody variant of the upper structure in Figure 2G, which binds to antigen B or epitope B, wherein ABR-A and ABR-B are optionally paired with each other via at least one disulfide bond. In some cases, CL-A and / or CH1-A may be omitted. In the upper right structure, the CH1-A and CL-A pair is omitted. The lower left structure includes (1) ABR-A that binds to antigen A or epitope A, having the same structure as the semi-antibody variant of the upper (in-box) structure in Figure 2G, except that VL-A is omitted and (VH-A) is sufficient to bind to antigen A or epitope A; and (2) ABR-B that binds to antigen B or epitope B, having the structure of the semi-antibody variant of the upper (in-box) structure in Figure 2G, wherein ABR-A and ABR-B are optionally paired with each other via at least one disulfide bond. In some cases, CL-A and / or CH1-A may be omitted. In the upper right structure, the CH1-A and CL-A pair is omitted. In Figure 2M, the upper left structure includes (1) ABR-A having the structure of the semi-antibody variant of the upper left structure in Figure 1G, and (2) ABR-B having the same structure as the semi-antibody variant of the upper (in-box) structure in Figure 2G, except that VL-B is omitted and (VH-B) is sufficient to bind to antigen B or epitope B, and ABR-A and ABR-B are paired with each other via at least one disulfide bond optionally. In some cases, one or more of CL-A, CH1-A, CL-B, and / or CH1-B may be omitted (e.g., the first and second structures from the left in the middle and bottom rows).The structure in the upper right includes (1) ABR-A that binds to antigen A or epitope A, having the same structure as the semi-antibody variant of the structure in the upper (box) of Figure 2G, except that VL-A is omitted and (VH-A) is sufficient to bind to antigen A or epitope A; and (2) ABR-B that binds to antigen B or epitope B, having the same structure as the semi-antibody variant of the structure in the upper (box) of Figure 2G, except that VL-B is omitted and (VH-B) is sufficient to bind to antigen B or epitope B, wherein ABR-A and ABR-B are optionally paired with each other via at least one disulfide bond. In some cases, one or more of CL-A, CH1-A, CL-B, and / or CH1-B may be omitted (e.g., the first and second structures from the right in the middle and bottom rows). The structures of antibodies having a structurally asymmetric format (e.g., multispecific antibodies) are not limited to those shown in Figures 2L-2M and their descriptions, but many other structures are possible, such as (1) ABR-A that binds to antigen A or epitope A having the structure of one of the structures shown in Figures 1 and 2A-2K and the half-antibody variant structure described therein, and (2) ABR-B that binds to antigen B or epitope B having another structure of the structure shown in Figures 1 and 2A-2K and the half-antibody variant structure described therein, where ABR-A and ABR-B are paired with each other via at least one optionally disulfide bond. Antibodies, antigen-binding antibody fragments, and multispecific antibodies having any of these structures are also included in the disclosure herein. [Figure 3A]A schematic diagram is provided of an antigen-binding structure ("AB-A / B / C") that binds to antigens A, B, and C and / or epitopes A, B, and C, which may be included in antibodies, antigen-binding antibody fragments, and multispecific antibodies (e.g., bispecific or trispecific antibodies). Such an AB-A / B / C comprises (1) an antigen-binding structure (AB-A / B) comprising at least one ABR-A and at least one ABR-B, and (2) at least one antigen-binding region (ABR-C) that binds to antigen C or epitope C, comprising a heavy chain variable domain C (VH-C) and optionally a light chain variable domain (VL-C). One or more of antigens A, B, and C may be the same as or different from each other, and one or more of epitopes A, B, and C may be the same as or different from each other. Although eight ABR-Cs are shown, the structure may include one or any number of ABR-Cs, for example, one, two, three, four, or more (for example, five, six, seven, or eight). In some cases, AB-A and / or ABR-A may include one or more of the structures in Figures 1A-1J or their descriptions. In some cases, ABR-B may include one or more of the structures in Figures 1A-1J or their descriptions. In some cases, AB-A / B may include one or more of the structures in Figures 2A-2K or their descriptions. In some cases, ABR-C may include one or more of the structures in Figures 1A-1J or their descriptions. AB-A / B and ABR-C may optionally associate with each other via one or more disulfide bonds, or optionally link with each other in any suitable manner via hinges or linkers. For example, the N-terminus or C-terminus of a polypeptide contained in ABR-C may be ligated to the N-terminus or C-terminus of a polypeptide contained in AB-A / B. [Figure 3B]The following schematic diagrams are provided of exemplary antibodies, antigen-binding antibody fragments, and multispecific antibodies (as encompassed by the structure and description in Figure 3A), comprising (1) an AB-A / B including the structure in the box in Figure 2G, and (2) one or more ABR-Cs (connected in series or linked at separate sites of the AB-A / B). Each of the one or more ABR-Cs comprises (i) (a) a polypeptide (which may be called heavy chain C) comprising a heavy chain variable domain C (VH-C) and a heavy chain constant domain C (CH-C) (CH-C may contain at least a heavy chain constant domain 1C (CH1-C)) from the N-terminus to the C-terminus, and (b) a polypeptide (which may be called light chain C) comprising a light chain variable domain C (VL-C) and a light chain constant domain C (CL-C) from the N-terminus to the C-terminus, wherein the heavy chain C and light chain C are optionally paired with each other via at least one disulfide bond, and (ii) a polypeptide comprising (a) a heavy chain C (which may be called heavy chain C), and (b) a polypeptide (which may be called light chain C), wherein the heavy chain C and light chain C are optionally paired with each other via at least one disulfide bond, and The structures may include: (iii) an Fv(Fv-C) that binds to antigen C or epitope C, selectively paired with each other via at least one disulfide bond (e.g., the structure in the lower right of Figure 1E); (iii) an scFv(scFv-C) that binds to antigen C or epitope C, comprising (a) VH-C, (b) an optional linker, and (c) VL-C from the N-terminus to the C-terminus (e.g., the structure in the box in Figure 1F); (iv) an scFab(scFab-C) that binds to antigen C or epitope C, comprising (a) VH-C, (b) CH-C (CH-C may include at least CH1-C), (c) an optional linker, (d) VL-C, and (e) CL-C from the N-terminus to the C-terminus (e.g., the structure in the box in Figure 1H); or (v) an sdAb(sdAb-C) that binds to antigen C or epitope C, comprising VH-C.In the cases of (i) and (ii) (i.e., Fab-C and Fv-C), either heavy chain C or light chain C is linked to heavy chain A or light chain A and / or heavy chain B or light chain B of AB-A / B, or heavy chain C and light chain C are linked to heavy chain A and light chain A, or light chain A and heavy chain A, and / or heavy chain B and light chain B, or light chain B and heavy chain B, respectively. In the cases of (iii) to (v) (i.e., scFv-C, scFab-C, and sdAb-C), the N-terminus or C-terminus of ABR-C is linked to heavy chain A, light chain A, heavy chain B, and / or light chain B of AB-A / B. Furthermore, (1) structures using ABR-A / B having other full-size antibody structures or variants thereof, including but not limited to those in Figures 2A-2M and their descriptions (e.g., those with one or more domains omitted, those with swapped domain positions, and / or half-antibody variants), and / or (2) (a) structures in Figure 1E and their descriptions (e.g., those with one or more domains omitted, those with swapped domain positions, and / or those with a hinge (Fab')), including but not limited to those, (b) other Fv structures or variants thereof, (c) structures in Figures 1F and 1G and their descriptions (e.g., those with one or more domains added, those with one or more domains omitted) (d) Other scFv-containing structures or variants thereof, including but not limited to those shown in Figures 1H and 1I and their descriptions (e.g., those with one or more domains added, those with one or more domains omitted, and / or those with the domain positions swapped), or structures using ABR-C having an sdAb structure or variant thereof, including but not limited to those shown in Figure 1J and its description (e.g., those with one or more domains added, those with one or more domains omitted, and / or those with the domain positions swapped), are further encompassed by this disclosure.Furthermore, although eight ABR-Cs are shown, a structure may contain one or any number of ABR-Cs, for example, one, two, three, four, or more (for example, five, six, seven, or eight). If two or more ABR-Cs are present, the structures of all ABR-Cs may be the same (for example, all scFv), or one or more of the ABR-Cs may have different structures (for example, scFv and Fab). [Figure 4A]Provided is a schematic diagram of an antigen-binding structure (referred to as "AB-A / B / C / D") that may be included in an antibody, an antigen-binding antibody fragment, and a multispecific antibody (e.g., a bispecific, trispecific, or tetravalent antibody), which binds to antigens A, B, C, and D and / or epitopes A, B, C, and D. Such AB-A / B / C / D includes (1) an antigen-binding structure (AB-A / B / C) that includes at least one ABR-A, at least one ABR-B, and at least one ABR-C, and (2) at least one antigen-binding region (ABR-D) that includes a heavy chain variable domain D (VH-D) and optionally a light chain variable domain (VL-D) and binds to antigen D or epitope D. One or more of antigens A, B, C, and D may be the same as or different from each other, and one or more of epitopes A, B, C, and D may be the same as or different from each other. Although eight ABR-Ds are shown, the structure may include one, any number, e.g., one, two, three, four, or more (e.g., five, six, seven, or eight) ABR-Ds. In some cases, AB-A and / or ABR-A may include one or more of the structures in FIGS. 1A-1J or descriptions thereof. In some cases, ABR-B may include one or more of the structures in FIGS. 1A-1J or descriptions thereof. In some cases, ABR-C may include one or more of the structures in FIGS. 1A-1J or descriptions thereof. In some cases, AB-A / B / C may include one or more of the structures according to FIGS. 3A-3B or descriptions thereof. In some cases, ABR-D may include one or more of the structures in FIGS. 1A-1J or descriptions thereof. AB-A / B / C and ABR-D may optionally be associated with each other via one or more disulfide bonds or may be linked to each other in any suitable manner via an optional hinge or linker. For example, the N-terminus or C-terminus of the polypeptide included in ABR-D may be linked to the N-terminus or C-terminus of the polypeptide included in AB-A / B / C. [Figure 4B]Schematic diagrams of exemplary antibodies, antigen-binding antibody fragments, and multispecific antibodies (as encompassed by the structure and description in Figure 4A) are provided, comprising: (1) AB-A / B including the structure in the box in Figure 2G; (2) one or more ABR-Cs (connected in series or at separate sites of AB-A / B); and (3) one or more ABR-Ds (connected in series or at separate sites of AB-A / B). Each of the one or more ABR-Cs may have a structure as shown in Figure 3B. Each of the one or more ABR-Ds comprises (i) (a) a polypeptide (which may be called heavy chain D) comprising a heavy chain variable domain D (VH-D) and a heavy chain constant domain D (CH-D) (CH-D may also include at least a heavy chain constant domain 1D (CH1-D)) from the N-terminus to the C-terminus, and (b) a polypeptide (which may be called light chain D) comprising a light chain variable domain D (VL-D) and a light chain constant domain D (CL-D) from the N-terminus to the C-terminus, wherein the heavy chain D and light chain D are optionally paired with each other via at least one disulfide bond, and (ii) (a) a polypeptide comprising a heavy chain D The structures may include: (iii) an Fv(Fv-D) that binds to antigen D or epitope D, selectively pairing with each other via at least one disulfide bond (e.g., the structure in the lower right of Figure 1E); (iii) an scFv(scFv-D) that binds to antigen D or epitope D, comprising (a) VH-D, (b) an optional linker, and (c) VL-D from the N-terminus to the C-terminus (e.g., the structure in the box in Figure 1F); (iv) an scFab(scFab-D) that binds to antigen D or epitope D, comprising (a) VH-D, (b) CH-D (CH-D may include at least CH1-D), (c) an optional linker, (d) VL-D, and (e) CL-D from the N-terminus to the C-terminus (e.g., the structure in the box in Figure 1H); or (v) an sdAb(sdAb-D) that binds to antigen D or epitope D, comprising VH-D.For Fab-C and Fv-C, either heavy chain C or light chain C is linked to heavy chain A or light chain A, or heavy chain C and light chain C are linked to heavy chain A and light chain A, respectively, or light chain A and heavy chain A, respectively. For Fab-D and Fv-D, either heavy chain D or light chain D is linked to heavy chain B or light chain B, or heavy chain D and light chain D are linked to heavy chain B and light chain B, respectively, or light chain B and heavy chain B, respectively. For scFv-C, scFab-C, and sdAb-C, the N-terminus or C-terminus of ABR-C is linked to heavy chain A and / or light chain A. For scFv-D, scFab-D, and sdAb-D, the N-terminus or C-terminus of ABR-D is linked to heavy chain B and / or light chain B.Furthermore, (1) structures using ABR-A / B having other full-size antibody structures or variants thereof, including but not limited to those in Figures 2A-2M and their descriptions (e.g., those with one or more domains omitted, those with swapped domain positions, and / or half-antibody variants), and / or (2) ABR-C and / or (3) ABR-D, including but not limited to (a) those in Figure 1E and their descriptions (e.g., those with one or more domains omitted, those with swapped domain positions, and / or those with a hinge (Fab')), (b) other Fv structures or variants thereof, (c) those in Figures 1F and 1G and their descriptions (e.g., those with one or more domains added, one or more domains The present disclosure further encompasses structures using ABR-C and / or ABR-D having sdAb structures or variants thereof, including, but not limited to, (d) other scFv-containing structures or variants thereof, including, but not limited to, (d) those in Figures 1H and 1I and their descriptions (e.g., with one or more domains added, with one or more domains omitted, and / or with domain positions swapped), or (e) those in Figure 1J and its description (e.g., with one or more domains added, with one or more domains omitted, and / or with domain positions swapped). Furthermore, although four ABR-Cs and four ABR-Ds are shown, the structure may include one or any number of ABR-Cs, for example, one, two, three, four, or more (e.g., five, six, seven, or eight) and / or one or any number of ABR-Ds, for example, one, two, three, four, or more (e.g., five, six, seven, or eight). If two or more ABR-Cs are present, the structures of all ABR-Cs may be the same (e.g., all scFv), or one or more of the ABR-Cs may have different structures (e.g., scFv and Fab).If two or more ABR-Ds exist, the structures of all ABR-Ds may be the same (e.g., all scFv), or one or more ABR-Ds may have different structures (e.g., scFv and Fab). Furthermore, the structures of ABR-C and ABR-D may or may not be the same. [Figure 4C]Further exemplary antibodies, antigen-binding antibody fragments, and multispecific antibodies (as encompassed by the structures and descriptions in Figure 4A) are provided, comprising: (1) the Fc region of an Ig molecule, each comprising two heavy chains, each comprising at least a CH2 domain and a CH3 domain; (2) one or more ABR-A (in series or linked to separate sites on the Fc); (3) one or more ABR-B (in series or linked to separate sites on the Fc); (4) one or more ABR-C (in series or linked to separate sites on the Fc); and (5) one or more ABR-D (in series or linked to separate sites on the Fc). Each of the one or more ABR-A may have the structure of (i) Fab-A described above, (ii) Fv-A described above, (iii) scFv-A described above, (iv) scFab-A described above, or (v) sdAb-A described above. Each of the one or more ABR-Bs may have the structure of (i) Fab-B described above, (ii) Fv-B described above, (iii) scFv-B described above, (iv) scFab-B described above, or (v) sdAb-B described above. Each of the one or more ABR-Cs may have the structure of (i) Fab-C described above, (ii) Fv-C described above, (iii) scFv-C described above, (iv) scFab-C described above, or (v) sdAb-C described above. Each of the one or more ABR-Ds may have the structure of (i) Fab-D described above, (ii) Fv-D described above, (iii) scFv-D described above, (iv) scFab-D described above, or (v) sdAb-D described above. For any of ABR-A, ABR-B, ABR-C, and ABR-D, in the cases of (i) and (ii) (i.e., Fab and Fv), either the heavy chain or light chain of Fab or Fv is ligated to the heavy chain of Fc (optionally, the N-terminus or C-terminus of the heavy chain), or the heavy chain and light chain of Fab or Fv are ligated to one heavy chain and the other heavy chain of Fc, respectively. For any of ABR-A, ABR-B, ABR-C, and ABR-D, in the cases of scFv, scFab, and sdAb, the N-terminus or C-terminus of scFv, scFab, or sdAb is ligated to the heavy chain of Fc (optionally, the N-terminus or C-terminus of the heavy chain).Regarding Fab, examples include those shown in Figure 1E and their descriptions (e.g., those with one or more domains omitted, those with swapped domain positions, and / or those with hinges (Fab')), but are not limited to these; any Fab structure or variant thereof may be used. Regarding Fv, any Fv structure or variant thereof may be used. Regarding scFv, examples include those shown in Figures 1F and 1G and their descriptions (e.g., those with one or more domains added, those with one or more domains omitted, and / or those with swapped domain positions), but are not limited to these; any scFv-containing structure or variant thereof may be used. Regarding scFab, examples include those shown in Figures 1H and 1I and their descriptions (e.g., those with one or more domains added, those with one or more domains omitted, and / or those with swapped domain positions), but are not limited to these; any scFab structure or variant thereof may be used. Regarding sdAb, the examples shown in Figure 1J and their descriptions (e.g., those with one or more domains added, those with one or more domains omitted, and / or those with swapped domain positions) are included, but any sdAb structure or variant thereof may be used, not limited to these. Furthermore, although one ABR-A, one ABR-B, one ABR-C, and one ABR-D are shown, the structure may include one or any number, for example, one, two, three, four, or more (e.g., five, six, seven, or eight) ABR-A, ABR-B, ABR-C, and ABR-D. If two or more of a given ABR (ABR-A, ABR-B, ABR-C, or ABR-D) exist, the structures of two or more of the ABRs may all be the same (e.g., all scFv), or one or more of the ABRs may have different structures (e.g., scFv and Fab). If two or more of a given ABR (ABR-A, ABR-B, ABR-C, or ABR-D) are present, the ABRs may be arranged in series, one of which may be connected to at least one heavy chain of Fc, or at least two of the ABRs may be connected to separate parts of Fc. [Figure 5A-N]Various exemplary structures are provided (included by the structures in Figures 2, 3, and 4 and their descriptions), particularly those including any of the structures in Figures 2G to 2K and the core structures in their descriptions. In Figure 5A, the structure is an ABR-C having (1) a core structure (AR-A / B) according to the structure in the box in Figure 2G, and (2) a structure of Fv(Fv-C) that binds to antigen C or epitope C, comprising (a) a polypeptide containing VH-C (which may be called heavy chain C), and (b) a polypeptide containing VL-C (which may be called light chain C), wherein the heavy chain C and light chain C are optionally paired with each other via at least one disulfide bond, ABR ABR-D having a structure of -C (for example, the lower right structure in Figure 1E) and (3) Fv (Fv-D) that binds to antigen D or epitope D, comprising (a) a polypeptide containing VH-D (which may be called heavy chain D) and (b) a polypeptide containing VL-D (which may be called light chain D), wherein heavy chain D and light chain D are optionally paired with each other via at least one disulfide bond, the ABR-D (for example, the lower right structure in Figure 1E). Structures in which Fv-C and Fv-D are located at the N-terminuses of heavy chain A and light chain B and heavy chain B, respectively, of the core structure (AR-A / B) in Figure 5A, but structures in which Fv-C and Fv-D are located at the C-terminuses of heavy chain A and B of the core structure (AR-A / B), are also encompassed by this disclosure. Although not explicitly shown, variants in which the core structure (AR-A / B) includes any of the structures in Figures 2G-2K are also included. Furthermore, variants in which one or more of ABR-A, ABR-B, ABR-C, and / or ABR-D are omitted are also included. In Figure 5B, the structures include (1) a core structure (AB-A / B / C / D) according to the structure in the upper left of Figure 5A, and (2) an ABR-E having a structure of Fv(Fv-E) that binds to antigen E or epitope C, comprising (a) a polypeptide containing VH-E (which may be called heavy chain E), and (b) a polypeptide containing VL-E (which may be called light chain E), wherein the heavy chain E and light chain E are optionally paired with each other via at least one disulfide bond (e.g., the structure in the lower right of Figure 1E).Heavy chain E and light chain E are located at the C-terminuses of heavy chain A and heavy chain B of the core structure (left structure), or at the C-terminuses of heavy chain B and heavy chain A (right structure). Although not explicitly shown, variants in which the core structure (AR-A / B / C / D) includes any of the structures in Figure 5A are also included. Furthermore, variants in which one or more of ABR-A, ABR-B, ABR-C, ABR-D, and / or ABR-E are omitted are also included. In Figure 5C, the structure includes (1) a core structure (AR-A / B) according to the structure in the box in Figure 2G, (2) an ABR-C having a scFv (scFv-C) structure that binds to antigen C or epitope C, comprising (a) VH-C, (b) an optional linker, and (c) VL-C from the N-terminus to the C-terminus, or from the C-terminus to the N-terminus, (e.g., the scFv structure above Figure 1F), and (3) an ABR-D having a scFv (scFv-D) structure that binds to antigen D or epitope D, comprising (a) VH-D, (b) an optional linker, and (c) VL-D from the N-terminus to the C-terminus, or from the C-terminus to the N-terminus, (e.g., the Fab structure above Figure 1F). scFv-C and scFv-D are located at the C-terminuses of heavy chain A and heavy chain B, respectively, of the core structure. Although not explicitly shown, variants in which the core structure (AR-A / B) includes any of the structures in Figures 2G-2K are also included. Furthermore, variants in which one or more of scFv-A, scFv-B, scFv-C, and / or scFv-D are replaced with the corresponding scFab structure (e.g., according to any of the scFab structures in Figure 1H), and / or one or more of ABR-A, ABR-B, ABR-C, and / or ABR-D are omitted. In Figure 5D, the structure includes (1) a core structure (AR-A / B) according to the structure in the box in Figure 2G, (2) an ABR-C containing scFv-C (as shown in Figure 5B), and (3) an ABR-D containing scFv-D (as shown in Figure 5B). scFv-C and scFv-D are located at the C-terminuses of light chain A and light chain B, respectively, of the core structure. Although not explicitly shown, variants in which the core structure (AR-A / B) includes any of the structures shown in Figures 2G-2K are also included.Furthermore, variants are also included in which one or more of scFv-A, scFv-B, scFv-C, and / or scFv-D are replaced by the corresponding scFab structure (for example, according to any of the scFab structures in Figure 1H), and / or one or more of ABR-A, ABR-B, ABR-C, and / or ABR-D are omitted. In Figure 5E, the structure includes (1) a core structure (AR-A / B) according to the structure in the box in Figure 2G, (2) an ABR-C containing scFv-C (as shown in Figure 5B), and (3) an ABR-D containing scFv-D (as shown in Figure 5B). scFv-C and scFv-D are located at the N-terminuses of heavy chain A and heavy chain B, respectively, of the core structure. Although not explicitly shown, variants are also included in which the core structure (AR-A / B) contains any of the structures in Figures 2G-2K. Furthermore, variants are also included in which one or more of scFv-A, scFv-B, scFv-C, and / or scFv-D are replaced by the corresponding scFab structure (for example, according to any of the scFab structures in Figure 1H), and / or one or more of ABR-A, ABR-B, ABR-C, and / or ABR-D are omitted. In Figure 5F, the structure includes (1) a core structure (AR-A / B) according to the structure in the box in Figure 2G, (2) an ABR-C containing scFv-C (as shown in Figure 5B), and (3) an ABR-D containing scFv-D (as shown in Figure 5B). scFv-C and scFv-D are located at the N-terminuses of light chain A and light chain B, respectively, of the core structure. Although not explicitly shown, variants are also included in which the core structure (AR-A / B) contains any of the structures in Figures 2G-2K. Furthermore, variants are also included in which one or more of scFv-A, scFv-B, scFv-C, and / or scFv-D are replaced with the corresponding scFab structure (for example, according to one of the scFab structures in Figure 1H), and / or one or more of ABR-A, ABR-B, ABR-C, and / or ABR-D are omitted.In Figure 5G, the structure is an ABR-E having the structure of (1) a core structure (AR-A / B) according to the structure in the box in Figure 2G, (2) an ABR-C containing scFv-C (as shown in Figure 5B), (3) an ABR-D containing scFv-D (as shown in Figure 5B), and (4) an scFv (scFv-E) that binds to antigen E or epitope E, and having (a) a VH-E, (b) an optional linker, and (c) a VL-E from the N-terminus to the C-terminus, or from the C-terminus to the N-terminus, for example, ABR-F having the scFv structure shown above in Figure 1F, and (5) an scFv (scFv-F) structure that binds to antigen F or epitope F, comprising (a) VH-F, (b) an optional linker, and (c) VL-F from the N-terminus to the C-terminus, or from the C-terminus to the N-terminus, ABR-F (e.g., the scFv structure shown above in Figure 1F), and (6) an scFv (scFv-G) structure that binds to antigen G or epitope G, comprising (a) VH-F, ( ABR-G (e.g., the scFv structure shown above in Figure 1F) comprising (b) an optional linker and (c) VL-G, and ABR-C having the structure of (7) an scFv (scFv-H) that binds to antigen H or epitope H, wherein ABR-C (e.g., the scFv structure shown above in Figure 1F) comprises (a) VH-H, (b) an optional linker and (c) VL-H from the N-terminus to the C-terminus, or from the C-terminus to the N-terminus, and ABR-C having the structure of (8) an scFv (scFv-I) that binds to antigen I or epitope I. ABR-I (e.g., the structure of scFv above Figure 1F) comprises (a) VH-I, (b) an optional linker, and (c) VL-I, from the N-terminus to the C-terminus, or from the C-terminus to the N-terminus, and ABR-J (e.g., the structure of scFv above Figure 1F) having the structure of scFv (scFv-J) that binds to antigen J or epitope J, comprising (a) VH-J, (b) an optional linker, and (c) VL-J, from the N-terminus to the C-terminus, or from the C-terminus to the N-terminus. scFv-C and scFv-D are located at the N-terminuses of heavy chain A and heavy chain B, respectively, of the core structure. scFv-E and scFv-F are located at the N-terminuses of light chain A and light chain B, respectively, of the core structure.scFv-G and scFv-H are located at the C-terminuses of light chain A and light chain B, respectively, of the core structure. scFv-I and scFv-J are located at the C-terminuses of heavy chain A and heavy chain B, respectively, of the core structure. One or more antigens A-J may be the same as or different from each other, and one or more epitopes A-J may be the same as or different from each other. Although not explicitly shown, variants in which the core structure (AR-A / B) contains any of the structures in Figures 2G-2K are also included. Furthermore, variants are also included in which one or more of scFv-A, scFv-B, scFv-C, scFv-D, scFv-E, scFv-F, scFv-G, scFv-H, scFv-I, and / or scFv-J are replaced with the corresponding scFab structure (for example, according to one of the scFab structures in Figure 1H), and / or one or more of ABR-A, ABR-B, ABR-C, ABR-D, ABR-E, ABR-F, ABR-G, ABR-H, ABR-I, and / or ABR-J are omitted. In Figure 5H, the structure is an ABR-C having (1) a core structure (AR-A / B) according to the structure in the box in Figure 2G, and (2) a Fab (Fab-C) structure that binds to antigen C or epitope C, comprising (a) a polypeptide (which may be called heavy chain C) from the N-terminus to the C-terminus containing VH-C and CH-C (CH-C may also contain CH1-C, hinge-C, CH2-C, and / or CH3-C), and (b) a polypeptide (which may be called light chain C) containing VL-C and CL-C, wherein the heavy chain C and light chain C are optionally paired with each other via at least one disulfide bond (e.g., the structure in the lower left (in the box) of Figure 1E), and (3) an ABR-D having a Fab (Fab-D) structure that binds to antigen D or epitope D, comprising (a) VH-D and CH-D (CH-D may also contain CH1-C, hinge-C, CH2-C, and / or CH3-C) from the N-terminus to the C-terminus.ABR-D (e.g., the structure in the lower left (in the box) of Figure 1E) comprises a polypeptide (which may be called heavy chain D) containing CH1-D, hinge-D, CH2-D, and / or CH3-D, and (b) a polypeptide (which may be called light chain D) containing VL-D and CL-D, wherein heavy chain D and light chain D are optionally paired with each other via at least one disulfide bond. Heavy chain C and light chain C may be located at the N-terminus of heavy chain A and the N-terminus of light chain A, respectively, or at the N-terminus of light chain A and the N-terminus of heavy chain A, respectively. Heavy chain D and light chain D may be located at the N-terminus of heavy chain B and the N-terminus of light chain B, respectively, or at the N-terminus of light chain B and the N-terminus of heavy chain B, respectively. Variants in which the core structure (AR-A / B) contains any of the structures in Figures 2G-2K are also included, although not explicitly shown. Furthermore, variants are also included in which one of the positions of the paired VH-VL and / or one of the positions of the paired CH1-CL are swapped, and / or one or more of ABR-A, ABR-B, ABR-C, and / or ABR-D are omitted. In Figure 5I, the structures are (1) a core structure (AR-A / B) according to the structure in the box in Figure 2G, (2) an ABR-C having the structure of Fab-C, comprising (a) a polypeptide (which may be called heavy chain C) from the N-terminus to the C-terminus, comprising VH-C and CH-C (where CH-C may also include CH1-C, hinge-C, CH2-C, and / or CH3-C), and (b) a polypeptide (which may be called light chain C) comprising VL-C and CL-C, wherein the heavy chain C and light chain C are optionally paired with each other via at least one disulfide bond, such as the structure in the lower left (in the box) of Figure 1E, and (3) an ABR-D having the structure of Fab-D, comprising (a) VH-D and CH-D (where CH-D is...ABR-D (e.g., the structure in the lower left (in the box) of Figure 1E) comprises a polypeptide (which may be called heavy chain D) containing CH1-D, hinge-D, CH2-D, and / or CH3-D, and (b) a polypeptide (which may be called light chain D) containing VL-D and CL-D, wherein heavy chain D and light chain D are optionally paired with each other via at least one disulfide bond. Heavy chain C and light chain C may be located at the C-terminus of heavy chain A and the C-terminus of light chain A, respectively, or at the C-terminus of light chain A and the C-terminus of heavy chain A, respectively. Heavy chain D and light chain D may be located at the C-terminus of heavy chain B and the C-terminus of light chain B, respectively, or at the C-terminus of light chain B and the C-terminus of heavy chain B, respectively. Variants in which the core structure (AR-A / B) contains any of the structures in Figures 2G-2K are also included, although not explicitly shown. Furthermore, variants are also included in which one of the positions of the paired VH-VL and / or one of the positions of the paired CH1-CL are swapped, and / or one or more of ABR-A, ABR-B, ABR-C, and / or ABR-D are omitted. In Figure 5J, the structure includes (1) a core structure (AR-A / B) following the structure in the upper left (inside the box) of Figure 2J, (2) an ABR-C having an scFv (scFv-C) structure that binds to antigen C or epitope C, comprising (a) VH-C, (b) an optional linker, and (c) VL-C from the N-terminus to the C-terminus, or from the C-terminus to the N-terminus, such as the ABR-C (e.g., the scFv structure in the upper left or upper right of Figure 1F), and (3) an ABR-D having an scFv (scFv-D) structure that binds to antigen D or epitope D, comprising (a) VH-D, (b) an optional linker, and (c) VL-D from the N-terminus to the C-terminus, or from the C-terminus to the N-terminus, such as the ABR-D (e.g., the scFv structure in the upper left or upper right of Figure 1F). scFv-C and scFv-D are located at the N-terminus of scFv-A and scFv-B, respectively, of the core structure. Although not explicitly shown, variants in which the core structure (AR-A / B) includes any of the structures shown in Figures 2J-2K are also included.Furthermore, variants in which one or more of ABR-A, ABR-B, ABR-C, and / or ABR-D are omitted, and / or one or more are CL and omitted, are also included. In Figure 5K, the structure includes (1) a core structure (AR-A / B) according to the structure in the upper left (inside the box) of Figure 2J, (2) an ABR-C having the scFv-C structure as described above for Figure 5J, and (3) an ABR-D having the scFv-D structure as described above for Figure 5J. scFv-C and scFv-D are located at the N-terminus of light chain A and the N-terminus of light chain B, respectively, of the core structure. Although not explicitly shown, variants in which the core structure (AR-A / B) includes any of the structures in Figures 2J to 2K are also included. Furthermore, variants in which one or more of ABR-A, ABR-B, ABR-C, and / or ABR-D are omitted, and / or one or more are CL and omitted, are also included. In Figure 5L, the structure includes (1) a core structure (AR-A / B) according to the structure in the upper left (inside the box) of Figure 2J, (2) an ABR-C having the scFv-C structure as described above for Figure 5J, and (3) an ABR-D having the scFv-D structure as described above for Figure 5J. scFv-C and scFv-D are located at the C-terminus of light chain A and the C-terminus of light chain B, respectively, of the core structure. Although not explicitly shown, variants in which the core structure (AR-A / B) includes any of the structures in Figures 2J to 2K are also included. Furthermore, variants in which one or more of ABR-A, ABR-B, ABR-C, and / or ABR-D are omitted, and / or one or more are CL and omitted, are also included. In Figure 5M, the structure includes (1) a core structure (AR-A / B) according to the structure in the upper left (inside the box) of Figure 2J, (2) an ABR-C having the scFv-C structure as described above for Figure 5J, and (3) an ABR-D having the scFv-D structure as described above for Figure 5J. scFv-C and scFv-D are located at the C-terminus of heavy chain A and the C-terminus of heavy chain B, respectively, of the core structure. Although not explicitly shown, variants in which the core structure (AR-A / B) includes any of the structures in Figures 2J to 2K are also included.Furthermore, variants in which one or more of ABR-A, ABR-B, ABR-C, and / or ABR-D are omitted, and / or one or more are CL, are also included. In Figure 5N, the structure is an ABR-E having (1) a core structure (AR-A / B / C / D) according to the structure in the upper left (in the box) of Figure 5J, and (2) an scFv (scFv-E) structure that binds to antigen E or epitope E, and which includes (a) VH-E, (b) an optional linker, and (c) VL-E from the N-terminus to the C-terminus, or from the C-terminus to the N-terminus, and (3) an scFv (scFv-F) that binds to antigen F or epitope F. ABR-F having the structure of (a) VH-F, (b) an optional linker, and (c) VL-F from the N-terminus to the C-terminus, or from the C-terminus to the N-terminus (for example, the scFv structure in the upper left or upper right of Figure 1F), and ABR-G having the structure of (4) an scFv (scFv-G) that binds to antigen G or epitope G, and having (a) VH-G, (b) an optional linker, and (c) VL-G from the N-terminus to the C-terminus, or from the C-terminus to the N-terminus, ABR-G ( For example, an ABR-H having the scFv structure shown in the upper left or upper right of Figure 1F, and (5) an scFv (scFv-H) structure that binds to antigen H or epitope H, wherein the ABR-H (for example, the scFv structure shown in the upper left or upper right of Figure 1F) contains (a) VH-H, (b) an optional linker, and (c) VL-F from the N-terminus to the C-terminus, or from the C-terminus to the N-terminus, Alternatively, the ABR-J includes an ABR-I (e.g., the scFv structure in the upper left or upper right of Figure 1F) having (a) a VH-I, (b) an optional linker, and (c) a VL-I from the C-terminus to the N-terminus, and an ABR-J (e.g., the scFv structure in the upper left or upper right of Figure 1F) having a structure of scFv (scFv-J) that binds to antigen J or epitope J, and having (a) a VH-J, (b) an optional linker, and (c) a VL-J from the N-terminus to the C-terminus, or from the C-terminus to the N-terminus. scFv-E and scFv-F are located at the N-terminus of light chain A and the N-terminus of light chain B, respectively, of the core structure.scFv-G and scFv-H are located at the C-terminus of light chain A and the C-terminus of light chain B, respectively, in the core structure. scFv-I and scFv-J are located at the C-terminus of heavy chain A and the C-terminus of heavy chain B, respectively, in the core structure. Although not explicitly shown, variants in which the core structure (AR-A / B / C / D) includes any of the structures in Figure 5J are also included. Furthermore, variants in which one or more of ABR-A, ABR-B, ABR-C, ABR-D, ABR-E, ABR-F, ABR-G, ABR-H, ABR-I, and / or ABR-J are omitted and / or one or more of the positions of the paired VH-VL are swapped are also included. [Figure 6] The structures of additional antibodies, antigen-binding antibody fragments, and multispecific antibodies are provided, which are variations of the antibody structure in the box in Figure 5A, but with the variable domains positioned in different orientations. Further variants are included, though not explicitly shown, in which one or more of the positions of the paired VH-VL are swapped, one or more of the positions of the paired CH1-CL are swapped, or one or more of the constant domains are omitted. [Modes for carrying out the invention]

[0248] definition Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those universally understood by those skilled in the art to which this disclosure belongs.

[0249] Furthermore, unless the context explicitly indicates otherwise, the singular forms "a," "an," and "the" used herein and in the appended claims include multiple references. Thus, a reference to "cell" refers to one or more cells and their equivalents, etc., known to those skilled in the art. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art.

[0250] Unless explicitly indicated otherwise, it should be understood that in any method disclosed or claimed herein involving two or more steps, the order in which the steps to be performed is not limited by the order of steps cited.

[0251] As used herein, the terms “about” or “approximately” mean, when used in reference to a specific enumerated number, that the value may vary by no more than 10% from the enumerated value. For example, as used herein, the expression “about 100” includes 90 and 110, as well as all values ​​in between (e.g., 91, 92, 93, 99, 99.1, 99.2, 99.3, 99.4, 100, 100.8, 100.9, 101, 106, 107, 108, 109, etc.).

[0252] The aspects and embodiments of the disclosure described herein should be understood to include the phrases "comprising," "consisting," and "consisting essentially of." Transitional phrases such as "comprising," "including," "having," "containing," "involving," and "composed of" should be understood as open-ended, meaning they include but are not limited to. Only the transitional phrases "consisting" and "essentially consisting of" are considered closed or semi-closed transitional phrases, respectively.

[0253] "Comprising" means that the enumerated elements are required, for example, in a composition, method, kit, etc., but other elements for forming a composition, method, kit, etc., may be included within the scope of the claims. For example, an expression cassette "comprising" a gene encoding a therapeutic polypeptide operably linked to a promoter is an expression cassette that may include other elements in addition to the gene and promoter, such as polyadenylated sequences, enhancer elements, other genes, linker domains, etc. The terms "including," "includes," "having," "has," and "with," as used herein, or variations thereof, are intended to be comprehensive in the same manner as the term "comprising."

[0254] "Essentially derived from" means, for example, a limitation on the scope of a composition, method, kit, etc., to a specific material or process that does not substantially affect the basic and novel characteristics of the composition, method, kit, etc. For example, an expression cassette "essentially derived from" a gene encoding a therapeutic polypeptide operably linked to a promoter and a polyadenylation sequence may include additional sequences, such as a linker sequence, as long as they do not substantially affect the transcription or translation of the gene. As another example, a variant or mutant polypeptide fragment "essentially derived from" an enumerated sequence has approximately 10 amino acid residues plus or minus the amino acid sequence of the enumerated sequence at the sequence boundary, based on the full-length naive polypeptide from which it is derived, for example, 10, 9, 8, 7, 6, 5, 4, 3, 2, or 1 fewer residues than the enumerated boundary amino acid residues, or 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 more residues than the enumerated boundary amino acid residues.

[0255] "~consisting of" means the exclusion of any element, process, or component from a composition, method, or kit that is not explicitly stated in the claim. For example, a polypeptide or polypeptide domain "consisting of" the enumerated sequences includes only the enumerated sequences.

[0256] "Differentiation cluster 28" or "CD28," also known as "Tp44," is a protein that plays a vital role in T cell development, activation, proliferation, and survival. Generally, unless otherwise indicated, it refers to any natural CD28 from any vertebrate source, including primates (e.g., humans or non-human primates such as cynomolgus monkeys) and mammals such as rodents (e.g., mice and rats). The term encompasses "full-length" untreated CD28 and any form of CD28 resulting from processing in cells, as well as naturally occurring variants of CD28, including, for example, splice variants or allele variants. In humans, CD28 is encoded by the CD28 gene on chromosome 2, located at 2q33.2 (NCBI). Human CD28 may have the amino acid sequence provided as GenBank:GenBank:AAH93698.1, which is 220 amino acids long. In one embodiment, human CD28 may have the amino acid sequence provided as SEQ ID NO: 100, or it may contain one or more equivalent / corresponding residues from a non-human species such as mouse, rodent, monkey, or ape.

[0257] The term "antibody" is used in its broadest sense herein and encompasses a variety of antibody structures, including, but is not limited to, monoclonal antibodies, polyclonal antibodies, multispecific antibodies (e.g., bispecific, tripspecific, and quadrupspecific antibodies), and / or antibody fragments (preferably referred to as "antigen-binding antibody fragments," which exhibit desirable antigen-binding activity). "Complete antibody," "complete Ab," "full-size antibody," "full-length antibody," "intact antibody," or "whole antibody" encompasses molecules having a structure substantially similar to that of a natural antibody, and in the case of IgG, IgD, or IgE, includes two immunoglobulin heavy chains and two immunoglobulin light chains. "Antigen-binding fragment" or "antigen-binding antibody fragment" refers to a portion of an intact antibody, or a combination of portions derived from an intact antibody, which binds to the antigen to which the intact antibody binds.

[0258] The terms “intact antibody,” “full-length antibody,” and “whole antibody” are used interchangeably herein to refer to antibodies having a structure substantially similar to that of natural antibodies. In some cases, antibodies include heavy (H) and light (L) chains interconnected by disulfide bonds. There are five main classes of antibodies: IgA, IgD, IgE, IgG, and IgM, some of which may be further divided into subclasses (isotypes), e.g., IgG1, IgG2, IgG3, IgG4, IgA1, and IgA2. The heavy chain constant domains corresponding to different classes of immunoglobulins are called α, δ, ε, γ, and μ, respectively. For example, an intact IgG (or IgD or IgE) antibody includes two immunoglobulin heavy chains and two immunoglobulin light chains. Thus, in some cases, antibodies according to this disclosure may include two pairs of heavy and light chains interconnected by disulfide bonds, or their antigen-binding fragments. Some intact antibodies contain multiple units, each containing two pairs of heavy and light chains interconnected by disulfide bonds. For example, intact IgA contains two units, and intact IgM contains five units. In other cases, antibodies according to this disclosure may instead contain multiple units (e.g., two, three, four, five, etc.), each containing two pairs of heavy and light chains interconnected by disulfide bonds, or their antigen-binding fragments.

[0259] In intact antibodies, each heavy chain contains variable domains such as the heavy chain variable domain ("VH") (also called the heavy chain variable region) and the heavy chain constant region ("CH"). In intact antibodies, CH contains heavy chain constant domain 1 (CH1), hinge, heavy chain constant domain 2 (CH2), and heavy chain constant domain 3 (CH3), with some exceptions, such as camel IgG2 or camel IgG3 containing CH hinge, CH2, and CH3, or shark antibodies (e.g., IgNAR) containing CH hinge, CH1, CH2, CH3, CH4, and CH5. In intact antibodies, each light chain consists of a light chain variable domain (VL) and a light chain constant domain (CL). Typically (with some exceptions such as nanobodies, camelid heavy chain antibodies, and IgNAR), one VH and one VL can form an antigen-binding structure. Therefore, a “set of variable domains” or “pair of variable domains” (or similar) of an antibody refers to a set or combination of VH and VL domains of the antibody.

[0260] VH and VL polypeptides can be further subdivided into highly variable regions called complementarity-determining regions (CDRs), with more conserved regions called framework regions (FRs) positioned between them. Each VH and VL polypeptide consists of three CDRs and four FRs arranged from the amino terminus to the carboxyl terminus in the following order: FR1, CDR1, FR2, CDR2, FR3, CDR3, FR4. The CDRs in the heavy chain are named "CDRH1," "CDRH2," and "CDRH3," respectively, while the CDRs in the light chain are named "CDRL1," "CDRL2," and "CDRL3." Therefore, a set of heavy chain CDRs (or similar) of an antibody means a set or combination of the antibody CDRH1, CDRH2, and CDRH3; a set of light chain CDRs (or similar) of an antibody means a set or combination of the antibody CDRL1, CDRL2, and CDRL3; and a set of heavy and light chain CDRs (or similar) of an antibody means a set or combination of the antibody CDRH1, CDRH2, CDRH3, CDRL1, CDRL2, and CDRL3. The FRs within the heavy chain are named "FRH1," "FRH2," "FR3," and "FRH4," respectively, and the FRs within the light chain are named "FRL1," "FRL2," "FRL3," and "FRL4." In certain embodiments of this disclosure, the FR of an antibody (or its antigen-binding fragment) is a heavy chain FR sequence encoded by a human germline coding sequence (e.g., VH1-03, VH1-69, VH2-05, VH3-09, VH3-23, VH4-31, VH4-39, VH4-4A, VH4-59, VH1-02, VH4-0B, VH4-59, VH1-18, or VH3-48 germline), and The amino acid consensus sequence may be identical to or may be naturally or artificially modified (light chain FR sequence) encoded by VK4-01, VK1-12, VK3-11, VK1-39, VK1-33, VK-2-28, VK3-15, VK1-05, VK3-20, VL2-11, VL1-51, VL1-40, VL2-11, VL6-57, VL2-14, or VL1-44 germline. The amino acid consensus sequence may be defined based on controlled comparative analysis of two or more CDRs.

[0261] The terms "heavy chain" or "HC" are used in their broadest sense and encompass polypeptides that include at least one immunoglobulin heavy chain domain or portion (i.e., at least one of VH, CH1, hinge, CH2, and / or CH3). Similarly, the terms "light chain" or "LC" are used in their broadest sense and encompass polypeptides that include at least one immunoglobulin light chain domain (i.e., at least one of VL and / or CL).

[0262] Generally, CDRs can be determined using any suitable manner. For example, CDR sequences can be determined based on a suitable numbering system for variable regions (e.g., Kabat numbering or IMGT numbering, or alternatively Chothia numbering, Martin numbering (also known as AbM numbering), Gelfand numbering, Honneger's numbering (also known as AHo numbering), or Chemical Computing Group (CCG) numbering, for example, by using X-ray crystallographic analysis to visualize specific epitope contact residues, it may be determined structurally (e.g., IgBlast(https: / / www.ncbi.nlm.nih.gov / igblast / ), Dondelinger et al., Front Immunol. 2018 Oct 16;9:2278, http: / / www.bioinf.org.uk / abs / info.html#cdrid, http: / / opig.stats.ox.ac.uk / webapps / newsabdab / sabpred / anarci / see), or combinations thereof may also be used.

[0263] Numbering of amino acid residues within antibody variable and constant domains can be carried out by the EU index or EU numbering system described in Kabat et al., Sequences of Proteins of Immunological Interest, 5th Ed. Public Health Service, National Institutes of Health, Bethesda, Md., (1991). Unless otherwise specified, the EU numbering system is used herein.

[0264] According to IMGT (International ImMunoGeneTics Information System for Immunoglobulins or Antibodies, T Cell Receptors, MHs, Immunoglobulin Superfamilies IgSFs, and MhSFs), the CH1 domain is located at amino acid positions 118–215 (EU numbering), and the hinge region is located at amino acid positions 216–230 (EU numbering). The term "CH1 domain" is used herein in a broad sense to encompass any naturally occurring corresponding heavy chain constant domain and / or region allotypes and their variants (which may include fewer or more amino acids and / or amino acid modifications), and to refer to a heavy chain region that includes at least 80% of heavy chain positions 118–215 (EU numbering), and in some cases also includes a portion of the hinge region (a portion of heavy chain positions 216–230 (EU numbering)) (e.g., up to position 218 or 220). The human IgG1 CH1 domain reference sequence corresponding to amino acid positions 118-220 according to EU numbering is provided herein as Sequence ID No. 1, which corresponds to the CH1 domain sequences of human IgG1 allotypes "IGHG1*01 (J00228)", "IGHG1*04 (JN582178)", or "IGHG1*07", and is an exemplary amino acid sequence of the wild-type (WT) CH1 domain. Human IgG1 CH1 domain reference sequence: ASTKGPSVFPLAPSSKSTSGGTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSSLGTQTYICNVNHKPSNTKVDKKVEPKSC (positions 118-220 according to EU numbering) (Sequence ID 1).

[0265] An alternative CH1 domain reference sequence for human IgG1 is, but is not limited to, Sequence ID No. 2, which corresponds to the CH1 domain sequence of human IgG1 allotypes "IGHG1*03(Y14737)" or "IGHG1*08". A substitute CH1 domain reference sequence for human IgG1 (compared to Sequence ID No. 1) 214R):ASTKGPSVFPLAPSSKSTSGGTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSSLGTQTYICNVNHKPSNTKVDK R VEPKSC (ranked 118th to 220th in the EU classification system) (Sequence ID 2).

[0266] These CH1 domain reference sequences are illustrative because the “CH1 domain” sequences used herein include any naturally occurring CH1 domain allotype or allele variant.

[0267] According to IMGT, the hinge is located at amino acid positions 216–230 (EU numbering). The term “hinge” is used broadly herein to refer to the heavy chain region containing at least 60% of hinge positions 216–230 (EU numbering). Human IgG1, IgG2, IgG3, and IgG4 hinge reference sequences corresponding to amino acid positions 231–340 by EU numbering are provided herein as SEQ ID NOs. 11, 12, 13, and 14, respectively, which are exemplary amino acid sequences of the wild-type (WT) hinge. Human IgG1 hinge reference sequence: EPKSCDKTHTCPPCP (ranked 216th to 230th in the EU numbering system) (Sequence ID 11). Human IgG2 hinge reference sequence: ERKCCVECPPCP (Sequence ID 12). Human IgG3 hinge reference sequence: ELKTPLGDTTHTCPRCPEPKSCDTPPPCPRCPEPKSCDTPPPCPRCPEPKSCDTPPPCPRCP(Sequence ID 13). Human IgG4 hinge reference sequence: ESKYGPPCPSCP (Sequence ID 14).

[0268] According to IMGT, the CH2 domain is located at amino acid positions 231–340 (EU numbering), which are referred to herein simply as "positions." The term "CH2 domain" is used herein in a broad sense to refer to the heavy chain region that includes at least 80% of heavy chain positions 231–340 (EU numbering). The human IgG1 CH2 domain reference sequence corresponding to amino acid positions 231–340 (EU numbering) is provided herein as Sequence ID No. 21, which is an exemplary amino acid sequence of the wild-type (WT) CH2 domain. Human IgG1 CH2 domain reference sequence: APELLGGPSVFLFPPKPKDTLMISRTPEVTCVVVDVSHEDPEVKFNWYVDGVEVHNAKTKPREEQYNSTYRVVSVLTVLHQDWLNGKEYKCKVSNKALPAPIEKTISKAK (SEQ ID NO: 21).

[0269] The enumerated CH2 domain reference sequences are illustrative, as the “CH2 domain” sequences used herein include any naturally occurring CH2 domain allotype or allele variant.

[0270] According to IMGT, the CH3 domain is located at amino acid positions 341–446 (EU numbering), which are referred to herein simply as "positions." The term "CH3 domain" is used herein in a broad sense to refer to a heavy chain region containing at least seven consecutive amino acid positions among heavy chain positions 341–446 (EU numbering). The CH3 domain reference sequence corresponding to amino acid positions 341–446 (EU numbering) is provided herein as Sequence ID No. 31, which corresponds to the CH3 domain sequence of human IgG1 allotypes "IGHG1*01 (J00228)" or "IGHG1*08" and is an exemplary amino acid sequence of the wild-type (WT) CH3 domain. Human IgG1 CH3 domain reference sequence: GQPREPQVYTLPPSRDELTKNQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSKLTVDKSRWQQGNVFSCSVMHEALHNHYTQKSLSLSPG (Sequence ID 31).

[0271] Possible alternative CH3 domain reference sequences for human IgG1 include, but are not limited to, Sequence ID 32, which corresponds to the CH3 domain sequence of human IgG1 allotype "IGHG1*03 (Y14737)", Sequence ID 33, which corresponds to the CH3 domain sequence of human IgG1 allotype "IGHG1*04 (JN582178)", and Sequence ID 34, which corresponds to the CH3 domain sequence of human IgG1 allotype "IGHG1*07". Alternative CH3 domain reference sequence 1 for human IgG1 (compared to SEQ ID NO: 31) 356E and 358M ): GQPREPQVYTLPPSR E E M TKNQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSKLTVDKSRWQQGNVFSCSVMHEALHNHYTQKSLSLSPG (Sequence ID 32). Alternative CH3 domain reference sequence 2 for human IgG1 (compared to SEQ ID NO: 31) 422I ): GQPREPQVYTLPPSRDELTKNQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSKLTVDKSRWQQGN I FSCSVMHEALHNHYTQKSLSLSPG (Sequence ID 33). Alternative CH3 domain reference sequence 3 for human IgG1 (compared to SEQ ID NO: 31) 431G ): GQPREPQVYTLPPSRDELTKNQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSKLTVDKSRWQQGNVFSCSVMHE G LHNHYTQKSLSLSPG (Sequence ID 34).

[0272] Furthermore, the CH3 domain reference sequences for human IgG2, IgG3, and IgG4 include, but are not limited to, sequence numbers 35, 36, and 37, respectively. Reference sequence of the CH3 domain of human IgG2: GQPREPQVYTLPPSREEMTKNQVSLTCLVKGFYPSDISVEWESNGQPENNYKTTPPMLDSDGSFFLYSKLTVDKSRWQQGNVFSCSVMHEALHNHYTQKSLSLSPG (Sequence ID 35) Reference sequence of the CH3 domain of human IgG3: GQPREPQVYTLPPSREEMTKNQVSLTCLVKGFYPSDIAVEWESSGQPENNYNTTPPMLDSDGSFFLYSKLTVDKSRWQQGNIFSCSVMHEALHNRFTQKSLSLSPG (Sequence ID 36) Reference sequence of the CH3 domain of human IgG4: GQPREPQVYTLPPSQEEMTKNQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSRLTVDKSRWQEGNVFSCSVMHEALHNHYTQKSLSLSLG (Sequence ID 37)

[0273] These CH3 domain reference sequences are illustrative because the “CH3 domain” sequences used herein include any naturally occurring CH3 domain allotype or allele variant. Therefore, amino acid modifications within variant CH3 domain polypeptides according to this disclosure may be compared to and / or incorporated into any parental CH3 domain polypeptide, such as, for example, the wild-type sequence (e.g., SEQ ID NO: 1) or any of those allele variants (e.g., any of SEQ ID NOs: 31-37). In some embodiments, the CH3 domain may further contain lysine at its C-terminus (i.e., K447 by EU numbering).

[0274] There are two main CL isotypes, kappa ("κ") and lambda ("λ"), and such CL domains are referred to herein as kappa CL domains ("CLκ" domains) and lambda CL domains ("CLλ" domains).

[0275] According to IMGT, the CLκ domain is located at amino acid positions 108–214 (EU numbering). The term “CLκ domain” is used herein in a broad sense to refer to a light chain region containing at least seven consecutive amino acid positions among the kappa light chain positions 108–214 (EU numbering). The human Ig CLκ domain reference sequence corresponding to amino acid positions 108–214 (EU numbering) is provided herein as Sequence ID No. 41, which is an exemplary amino acid sequence of the wild-type (WT) CLκ domain. Human Ig CLκ domain reference sequence: RTVAAPSVFIFPPSDEQLKSGTASVVCLLNNFYPREAKVQWKVDNALQSGNSQESVTEQDSKDSTYSLSSTLTLSKADYEKHKVYACEVTHQGLSSPVTKSFNRGEC (ranked 108th to 214th in EU numbering) (Sequence ID 41).

[0276] According to IMGT, the CLλ domain is located at amino acid positions 107–215 (EU numbering). The term "CLλ domain" is used herein in a broad sense to refer to a light chain region containing at least seven consecutive amino acid positions among lambda light chain positions 107–215 (EU numbering). The CLλ domain reference sequence corresponding to amino acid positions 107–215 (EU numbering) is provided herein as Sequence ID No. 42, which is an exemplary amino acid sequence of the wild-type (WT) CLλ domain. Human Ig CLλ domain reference sequence: GQPKAAPSVTLFPPSSEELQANKATLVCLISDFYPGAVTVAWKADSSPVKAGVETTTPSKQSNNKYAASSYLSLTPEQWKSHRSYSCQVTHEGSTVEKTVAPTECS (ranked 107th to 215th according to EU numbering) (Sequence ID 42).

[0277] Various standard sequences (corresponding to different allotypes) of the constant domains of human IgG1, IgG2, IgG3, and IgG4 are known in the art and can be found, for example, in Vidarsson et al., Front Immunol. 2014 Oct 20;5:520 and U.S. Patent No. 9150663, which are incorporated herein by reference in their entirety. Again, these reference sequences are illustrative, as they include any naturally occurring human IgG1, IgG2, IgG3, and IgG4 allotypes.

[0278] The “Fc region” is the C-terminal region of the immunoglobulin heavy chain, which includes at least a portion of the constant region, including the native Fc region and variant Fc regions. The Fc region of the human IgG heavy chain may extend from Asp221 to the carboxyl terminus of the heavy chain. However, the C-terminal lysine (Lys447) of the Fc region may or may not be present. Unless otherwise specified herein, the numbering of amino acid residues in the Fc region or constant region follows the EU numbering system, as described in Kabat et al., Sequences of Proteins of Immunological Interest, 5th Ed., Public Health Service, National Institutes of Health, Bethesda, Md., 1991.

[0279] The term "effector function" of an antibody refers to the biological activity resulting from the antibody's Fc region, which varies depending on the antibody class or isotype. Exemplary effector functions include complement (e.g., C1q) binding and complement-dependent cell-mediated cytotoxicity (CDC), Fc receptor binding, antibody-dependent cell-mediated cytotoxicity (ADCC), phagocytosis, downregulation of cell surface receptors (e.g., B cell receptors), and B cell activation.

[0280] "Antibody antigen-binding fragments" or "antigen-binding antibody fragments" include any naturally occurring, enzymatically obtainable, synthetic (e.g., with rearranged domain order compared to naturally occurring antibodies), or genetically modified polypeptides, proteins, or glycoproteins that contain an antigen-binding antibody domain (e.g., a VH domain or VH and VL domains) and specifically bind to an antigen to form a complex. Exemplary antigen-binding antibody fragments include Fv, fragment antigen-binding ("Fab") fragments, single-chain Fab (scFab), Fab' fragments, Fab' containing free sulfhydryl groups ("Fab'-SH'"), F(ab')2 fragments, F(ab')3 fragments, diabodies, triabodies, tetrabodies, linear antibodies, single-chain antibody molecules (e.g., single-chain variable fragments ("scFv")), tandem scFv, scFv-Fc, scFv-CH (e.g., scFv-CH3, scFv -CH2, scFv-CH1, scFv-CH2 / CH3, scFv-CH1 / CH2, scFv-CH1 / CH3, scFv-CH1 / CH2 / CH3, scFv-CH1 / Hinge / CH2 / CH3, Mini Body, etc.), scFv-Zipper, Tandem scFv-Fc, Tandem scFv-CH (e.g., Tandem scFv-CH3, Tandem scFv-CH2, Tandem scFv-CH1, Tandem scFv-CH2 / CH3, Tandem scFv-C) H1 / CH2, Tandem scFv-CH1 / CH3, Tandem scFv-CH1 / CH2 / CH3, Tandem scFv-CH1 / Hinge / CH2 / CH3, etc.), Tandem scFv-Zipper, Diabody-Fc, Diabody-CH (e.g., Diabody-CH3, Diabody-CH2, Diabody-CH1, Diabody-CH2 / CH3, Diabody-CH1 / CH2, Diabody-CH1 / CH3, Diabody-CH1 / CH2) / CH3, diabody-CH1 / hinge / CH2 / CH3 etc.), diabody-zipper, single-domain antibody (sdAb), nanobody or VHH (i.e., VH domain only and no VL), tandem sdAb or tandem nanobody, sdAb-Fc or nanobody-Fc, sdAb-CH or nanobody-CH (e.g., sdAb-CH3, sdAb-CH2, sdAb-CH1, sdAb-CH2 / CH3, sdAb-CH1 / CH2,Examples of monospecific or multispecific antibodies formed from one or more antibody fragments such as sdAb-CH1 / CH3, sdAb-CH1 / CH2 / CH3, sdAb-CH1 / Hinge / CH2 / CH3, etc., heavy-chain-only antibodies (HCAb), camel Ig, immunoglobulin novel antigen receptors (IgNAR), any of the aforementioned “half-antibody” variants (where structure permits), and the aforementioned antibody fragments include, but are not limited to, monospecific or multispecific antibodies. Further exemplary antigen-binding antibody fragments include, but are not limited to, the hypervariable regions of antibodies (e.g., isolated complementarity-determining regions (CDRs) such as the CDR3 peptide), or minimal recognition units of amino acid residues mimicking the restricted FR3-CDR3-FR4 peptide, and small modular immunoassays (SMIPs). In some embodiments, the antibodies described herein (e.g., multispecific antibodies) include one or more Fab, scFv, scFab, sdAb, and / or IgG.

[0281] For a discussion of a specific antibody fragment, see, for example, Hudson et al. Nat. Med. 9:129-134 (2003). For a discussion of Fab and F(ab')2 fragments containing salvage receptor-binding epitope residues and exhibiting increased in vivo half-lives, see U.S. Patent No. 5,869,046. Diabodies are antibody fragments having two antigen-binding sites that may be bivalent or bispecific. See, for example, EP404,097, WO1993 / 01161, Hudson et al. Nat. Med. 9:129-134 (2003), and Hollinger et al. Proc. Natl. Acad. Sci. USA 90:6444-6448 (1993). Triabodies and tetrabodies are also described in Hudson et al. Nat. Med. 9:129-134 (2003). A single-domain antibody is an antibody fragment comprising all or part of the heavy chain variable domains or all or part of the light chain variable domains of an antibody. In certain embodiments, the single-domain antibody is a human single-domain antibody (see, for example, Domantis, Inc., Waltham, Mass, U.S. Patent No. 6,248,516 B1). Antibody fragments can be prepared by a variety of techniques, including, but not limited to, proteolytic digestion of intact antibodies and production by recombinant host cells (e.g., E. coli or phages), as described herein.

[0282] Antibody antigen-binding fragments typically contain at least one variable domain. The variable domain may be of any size or amino acid composition and generally contains at least one CDR, which is adjacent to or in-frame with one or more framework sequences. In antigen-binding fragments having a VH associated with a VL, the VH and VL may be positioned relative to each other in any preferred configuration. For example, the variable region may be a dimer and may include VH-VH, VH-VL, or VL-VL dimers. Alternatively, antibody antigen-binding fragments may contain a monomeric VH domain or a VL domain.

[0283] In certain embodiments, the antigen-binding fragment of the antibody may include at least one variable domain covalently bound to at least one constant domain. Non-limiting and exemplary configurations of variable and constant domains that may be found in the antigen-binding fragment of the antibody of the Disclosure include (i) VH-CH1, (ii) VH-CH2, (iii) VH-CH3, (iv) VH-CH1-CH2, (V) VH-CH1-CH2-CH3, (vi) VH-CH2-CH3, (vii) VH-CL, (viii) VL-CH1, (ix) VL-CH2, (x) VL-CH3, (xi) VL-CH1-CH2, (xii) VL-CH1-CH2-CH3, (xiii) VL-CH2-CH3, and (xiv) VL-CL. In any configuration of the variable domain and constant domain, including any of the exemplary configurations listed above, the variable domain and constant domain may be directly linked to each other or linked by a complete or partial hinge or linker region. The hinge region may consist of at least two (e.g., 5, 10, 15, 20, 40, 60, or more) amino acids, thereby providing a flexible or semi-flexible linkage between adjacent variable domains and / or constant domains in a single polypeptide molecule. Furthermore, the antigen-binding fragment of the antibody of this disclosure may include homodimers or heterodimers (or other polymers) of any of the variable domain configurations and constant domain configurations listed above, non-covalently linked to each other and / or to one or more monomeric VH or VL domains (e.g., by disulfide bonds).

[0284] The terms “scFv,” “single-stranded Fv,” or “single-stranded variable fragment” refer to a fusion protein comprising at least one VH and at least one VL of an antibody, wherein the VH and VL are linked in a continuum, and the scFv retains the specificity of the antibody from which it is derived (the antibody from which the VH and VL are derived). Unless otherwise specified, as used herein, an scFv may have VH and VL in either order with respect to the N-terminus and C-terminus of a polypeptide, for example. For example, VH and VL may be linked via a linker such as a synthetic and / or flexible polypeptide linker, and the scFv may be expressed as a single-stranded polypeptide. If the linker links VH and VL, the scFv may include a VL-linker-VH or VH-linker-VL structure in the direction from the N-terminus to the C-terminus. If the linker links VH and VL, the linker may be any suitable linker, but is not limited to any of the linkers described herein. In some cases, VH and VL are linked by one or more disulfide bonds, either additionally or alternatively. In certain specific cases, the VH and / or VL sequences may be modified to include cysteine ​​residues that enable such disulfide bonds (e.g., one or more amino acids may be substituted) (see, e.g., Weatherill et al., Protein Eng Des Sel. 2012 Jul;25(7):321-9). For a discussion of scFv fragments, see, e.g., Pluckthun, in The Pharmacology of Monoclonal Antibodies, vol.113, Rosenburg and Moore eds., (Springer-Verlag, New York), pp.269-315 (1994). See also WO93 / 16185, and U.S. Patents 5,571,894 and 5,587,458.

[0285] As used herein, a “half-antibody” variant of a given antibody or antigen-binding antibody fragment refers to an antigen-binding antibody structure that contains a symmetrical or essentially symmetrical half of the given antibody or antigen-binding antibody fragment. Therefore, if a given antibody or its antigen-binding fragment is a homodimer (or essentially a homodimer), its half-antibody variant contains the corresponding monomer. For example, a half-antibody variant of intact IgG contains one (but not two) set of heavy chains containing VH, CH1, hinge, CH2, and CH3, and light chains containing VL and CL. Similarly, a half-antibody variant of scFv-Fc contains one (but not two) polypeptides containing scFv, hinge (or linker), CH2, and CH3, and a half-antibody variant of a minibody contains one (but not two) polypeptides containing scFv, hinge (or linker), and CH3. Since both the scFv-Fc semi-antibody variant and the minibody semi-antibody variant are single-chain molecules, they can be referred to as the scFv-Fc single-chain variant and the minibody single-chain variant, respectively. Similarly, the camel Ig (or camel IgG such as camel IgG2 or camel IgG3) semi-antibody variant contains one (but not two) polypeptide including VH, hinge (or linker), CH2, and CH3, and the IgNAR semi-antibody variant contains one (but not two) polypeptide including VH, hinge (or linker), CH1, CH2, CH3, CH4, and CH5. Since both the camel Ig semi-antibody variant and the IgNAR semi-antibody variant are single-chain molecules, they can be referred to as the camel Ig single-chain variant and the IgNAR single-chain variant, respectively.

[0286] The term "linker" refers to a variable-length construct that connects two or more domains or parts of a polypeptide, or connects two or more polypeptides. In some cases, linkers are used to confer flexibility, improved spatial organization, proximity, etc., and in such cases they may be called flexible linkers. Exemplary linkers may consist of one or more amino acids, optionally 1 to 50 amino acids, e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 amino acids. In some embodiments, linkers may consist mainly of or entirely of G, S, and / or A amino acid residues. In some embodiments, the linker may include, or consist of, an amino acid sequence selected from the group consisting of GGGGS (SEQ ID NO: 51, which may also be called "G4S"), GGGS (SEQ ID NO: 52, which may also be called "G3S"), GGGGGS (SEQ ID NO: 53, which may also be called "G5S"), G, GG, GGG, GS, SG, GGS (which may also be called "G2S"), GSG, SGG, GSS, SGS, and SSG. In some embodiments, the linker may include, or consist of, multiple repeats (e.g., 2, 3, 4, 5, or more repeats) of an amino acid sequence selected from the group consisting of G, GS, SG, GGS, GSG, SGG, GSS, SGS, SSG, and any combination thereof. If a linker contains or consists of multiple iterations of G5S, G4S, G3S, G2S, GS, or G, the linker may optionally be called a (G5S)n linker, a (G4S)n linker, a (G3S)n linker, a (G2S)n linker, a (GS)n linker, or a (G)n linker (where n is a natural number, arbitrarily selected from 1 to 20, e.g., 2, 3, 4, 5). In certain embodiments, the linker may contain two or three iterations of sequence number 51, i.e., sequences GGGGSGGGGS (sequence number 54) or GGGGSGGGGSGGGGS (sequence number 55), which may optionally be called a (G4S)2 linker or a (G4S)3 linker, respectively.

[0287] "Monoclonal antibody" or "mAb" refers to an antibody obtained from a substantially homogeneous population of antibodies, that is, the individual antibodies within that population are identical and / or bind to the same epitope, except for potential variant antibodies (e.g., including naturally occurring mutations and / or substitutions, or arising during the production of the monoclonal antibody preparation), and such variants are generally present in small amounts. In contrast to polyclonal antibody preparations, which typically contain d...

Claims

1. Anti-human differentiation cluster 28 (CD28) antibody or antigen-binding antibody fragment, A first heavy chain variable domain (VH-1) comprising a first heavy chain complementarity determining region (CDR) 1 (CDRH1-1), a first heavy chain CDR2 (CDRH2-1), and a first heavy chain CDR3 (CDRH3-1), and / or It comprises a first light chain variable domain (VL-1) including a first light chain CDR1 (CDRL1-1), a first light chain CDR2 (CDRL2-1), and a first light chain CDR3 (CDRL3-1), An anti-human differentiation cluster 28 (CD28) antibody or antigen-binding antibody fragment thereof, wherein the antibody or antigen-binding antibody fragment comprises a CDR amino acid sequence according to any one of those listed in Table 1B and / or 12B, or a variant thereof having at least about 50%, 60%, 70%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity.

2. (a) The amino acid sequence of CDRH1-1 includes, or is composed of, one of the heavy chain complementarity determining region 1 (CDRH1) amino acid sequences included in any one of the heavy chain variable domain (VH) amino acid sequences listed in Table 1A and / or 12A, and / or one of the CDRH1 amino acid sequences listed in Table 1B and / or 12B. (b) The amino acid sequence of CDRH2-1 includes, or consists of, one of the heavy chain complementarity determining region 2 (CDRH2) amino acid sequences included in any one of the VH amino acid sequences listed in Table 1A and / or 12A, and / or one of the CDRH2 amino acid sequences listed in Table 1B and / or 12B, and / or (c) The amino acid sequence of CDRH3-1 includes, or consists of, one of the heavy chain complementarity determining region 3 (CDRH3) amino acid sequences included in any one of the VH amino acid sequences listed in Table 1A and / or 12A, and / or one of the CDRH3 amino acid sequences listed in Table 1B and / or 12B, and / or (d) The amino acid sequence of CDRL1-1 includes, or is composed of, a light chain complementarity determining region 1 (CDRL1) amino acid sequence contained in any one of the light chain variable domain (VL) amino acid sequences listed in Table 1A and / or 12A, and / or any one of the CDRL1 amino acid sequences listed in Table 1B and / or 12B. (e) The amino acid sequence of CDRL2-1 includes, or consists of, a light chain complementarity determining region 2 (CDRL2) contained in any one of the VL amino acid sequences listed in Table 1A and / or 12A, and / or any one of the CDRL2 amino acid sequences listed in Table 1B and / or 12B, and / or (f) The anti-human CD28 antibody or antigen-binding antibody fragment according to claim 1, wherein the amino acid sequence of CDRL3-1 includes, or comprises, one of the light chain complementarity determining region 3 (CDRL3) included in any one of the VL amino acid sequences listed in Table 1A and / or 12A, and / or one of the CDRL3 amino acid sequences listed in Table 1B and / or 12B.

3. (a) A set of heavy chain CDR amino acid sequences of a first anti-CD28 antibody selected from antibodies having amino acid sequences listed in Tables 1A to 1D and / or 12A to 12D, (b) A set of light chain CDR amino acid sequences of a first anti-CD28 antibody selected from antibodies having amino acid sequences listed in Tables 1A to 1D and / or 12A to 12D, (c) A set of heavy and light chain CDR amino acid sequences of a first anti-CD28 antibody selected from antibodies having amino acid sequences listed in Tables 1A to 1D and / or 12A to 12D, and / or (d) an anti-human CD28 antibody or antigen-binding antibody fragment according to claim 1 or 2, comprising: (d) a set of heavy chain CDR amino acid sequences of a first anti-CD28 antibody selected from an enumerated set of antibodies having amino acid sequences in Tables 1A to 1D and / or 12A to 12D; and a set of light chain CDR amino acid sequences of a second anti-CD28 antibody selected from an antibody having amino acid sequences enumerated in Tables 1A to 1D and / or 12A to 12D.

4. (A) The VH-1 and the VL-1, (1) The amino acid sequences of CDRH1-1, CDRH2-1, and CDRH3-1 each contain or consist of the amino acid sequences of CDRH1, CDRH2, and CDRH3 contained in the VH of the first anti-CD28 antibody, (2) The amino acid sequences of CDRL1-1, CDRL2-1, and CDRL3-1 each contain or consist of the amino acid sequences of CDRL1, CDRL2, and CDRL3 contained in the VL of the first anti-CD28 antibody, The first anti-CD28 antibody described above, (I) Any one of the following anti-CD28 antibodies listed in Tables 1A to 1D: (1) Antibody No. 1, (2) Antibody No. 21, (3) Antibody No. 28, (4) Antibody No. 46, (5) Antibody No. 57, (6) Antibody No. 61, or (7) Antibody No. 68, and / or (II) Any one of the following anti-CD28 antibodies listed in Tables 1A-1D and / or 12A-12D: (i) antibody number 1, (ii) antibody number 2, (iii) antibody number 3, (iv) antibody number 4, (v) antibody number 5, (vi) antibody number 6, (vii) antibody number 7, (viiii) antibody number 8, (ix) antibody number 9, (x) antibody number 10, (xi) antibody number 11, (xii) antibody number 12, (xiiii) antibody number 13, (xiv) antibody number 14, (xv) antibody number 15, (xvi) antibody number 16, (xvii) antibody number 17, (xviiii) antibody number 1 8, (xix) Antibody number 19, (xx) Antibody number 20, (xxi) Antibody number 21, (xxi-a) Antibody number 21a, (xxi-b) Antibody number 21b, (xxi-c) Antibody number 21c, (xxi-d) Antibody number 21d, (xxi-e) Antibody number 21e, (xxi-f) Antibody number 21 f, (xxii) Antibody number 22, (xxiii) Antibody number 23, (xxiv) Antibody number 24, (xv) Antibody number 25, (xvi) Antibody number 26, (xvii) Antibody number 27, (xviii) Antibody number 28, (xviii-a) Antibody number 28a, (xviii-b) Antibody number 28b , (xviii-c) Antibody number 28c, (xviii-d) Antibody number 28d, (xviii-e) Antibody number 28e, (xviii-f) Antibody number 28f, (xix) Antibody number 29, (xxx) Antibody number 30, (xxxi) Antibody number 31, (xxxii) Antibody number 32, (xxxi ii) Antibody number 33, (xxxiv) Antibody number 34, (xxxv) Antibody number 35, (xxxvi) Antibody number 36, (xxxvii) Antibody number 37, (xxxviii) Antibody number 38, (xxxix) Antibody number 39, (xl) Antibody number 40, (xli) Antibody number 41, (xlii) Antibody number 42, (xliii) Antibody number 43, (xliv) Antibody number 44, (xlv) Antibody number 45, (xlvi) Antibody number 46, (xlvi-a) Antibody number 46a, (xlvi-b) Antibody number 46b, (xlvi-c) Antibody number 46c, (xlvi-d) Antibody number 46d, (x lvi-e) Antibody number 46e, (xlvii) Antibody number 47, (xlviii) Antibody number 48, (xlix) Antibody number 49, (l) Antibody number 50, (li) Antibody number 51, (lii) Antibody number 52, (liii) Antibody number 53, (liv) Antibody number 54, (lv) Antibody number 55,(lvi) Antibody number 56, (lvii) Antibody number 57, (lvii-a) Antibody number 57a, (lvii-b) Antibody number 57b, (lvii-c) Antibody number 57c, (lvii-d) Antibody number 57d, (lvii-e) Antibody number 57e, (lvii-f) Antibody number 57f, (lviii) Antibody number 58, (lix) Antibody number 59, (lx) Antibody number 60, (lxi) Antibody number 61, (lxi-a) Antibody number 61a, (lxi-b) Antibody number 61b, (lxi-c) Antibody number 61c, (lxi-d) Antibody number 61d, (lxi-e) Antibody number 61 e, (lxii) antibody number 62, (lxiii) antibody number 63, (lxiv) antibody number 64, (lxv) antibody number 65, (lxvi) antibody number 66, (lxvii) antibody number 67, (lxviiii) antibody number 68, (lxviiii-a) antibody number 68a, (lxviiii-b) antibody number 68b, (lxviiii-c) antibody number 68c, (lxviiii-d) antibody number 68d, (lxviiii-e) antibody number 68e, (lxviiii-f) antibody number 68f, or (lxix) antibody number 69, the above VH-1 and the above VL-1, or (B) The VH-1 and optionally the VL-1, wherein the amino acid sequences of the CDRH1-1, CDRH2-1, and CDRH3-1 are (I) Any one of the following anti-CD28 antibodies listed in Tables 1A to 1D: (1) antibody number 70 or (2) antibody number 83, and / or (II) Any one of the following anti-CD28 antibodies listed in Tables 1A-1D and / or 12A-12D: (i) antibody number 1, (ii) antibody number 2, (iii) antibody number 3, (iv) antibody number 4, (v) antibody number 5, (vi) antibody number 6, (vii) antibody number 7, (viiii) antibody number 8, (ix) antibody number 9, (x) antibody number 10, (xi) antibody number 11, (xii) antibody number 12, (xiiii) antibody number 13, (xiv) antibody number 14, (xv) antibody number 15, (xvi) antibody number 16, (xvii) antibody number 17, (xviiii) antibody number 1 8, (xix) Antibody number 19, (xx) Antibody number 20, (xxi) Antibody number 21, (xxi-a) Antibody number 21a, (xxi-b) Antibody number 21b, (xxi-c) Antibody number 21c, (xxi-d) Antibody number 21d, (xxi-e) Antibody number 21e, (xxi-f) Antibody number 21 f, (xxii) Antibody number 22, (xxiii) Antibody number 23, (xxiv) Antibody number 24, (xv) Antibody number 25, (xvi) Antibody number 26, (xvii) Antibody number 27, (xviii) Antibody number 28, (xviii-a) Antibody number 28a, (xviii-b) Antibody number 28b , (xviii-c) Antibody number 28c, (xviii-d) Antibody number 28d, (xviii-e) Antibody number 28e, (xviii-f) Antibody number 28f, (xix) Antibody number 29, (xxx) Antibody number 30, (xxxi) Antibody number 31, (xxxii) Antibody number 32, (xxxi ii) Antibody number 33, (xxxiv) Antibody number 34, (xxxv) Antibody number 35, (xxxvi) Antibody number 36, (xxxvii) Antibody number 37, (xxxviii) Antibody number 38, (xxxix) Antibody number 39, (xl) Antibody number 40, (xli) Antibody number 41, (xlii) Antibody number 42, (xliii) Antibody number 43, (xliv) Antibody number 44, (xlv) Antibody number 45, (xlvi) Antibody number 46, (xlvi-a) Antibody number 46a, (xlvi-b) Antibody number 46b, (xlvi-c) Antibody number 46c, (xlvi-d) Antibody number 46d, (x lvi-e) Antibody number 46e, (xlvii) Antibody number 47, (xlviii) Antibody number 48, (xlix) Antibody number 49, (l) Antibody number 50, (li) Antibody number 51, (lii) Antibody number 52, (liii) Antibody number 53, (liv) Antibody number 54, (lv) Antibody number 55,(lvi) Antibody number 56, (lvii) Antibody number 57, (lvii-a) Antibody number 57a, (lvii-b) Antibody number 57b, (lvii-c) Antibody number 57c, (lvii-d) Antibody number 57d, (lvii-e) Antibody number 57e, (lvii-f) Antibody number 57f, (lv iii) Antibody number 58, (lix) Antibody number 59, (lx) Antibody number 60, (lxi) Antibody number 61, (lxi-a) Antibody number 61a, (lxi-b) Antibody number 61b, (lxi-c) Antibody number 61c, (lxi-d) Antibody number 61d, (lxi-e) Antibody number 61e, (lxi i) Antibody number 62, (lxiii) Antibody number 63, (lxiv) Antibody number 64, (lxv) Antibody number 65, (lxvi) Antibody number 66, (lxvii) Antibody number 67, (lxviii) Antibody number 68, (lxviii-a) Antibody number 68a, (lxviii-b) Antibody number 68b , (lxviii-c) antibody number 68c, (lxviii-d) antibody number 68d, (lxviii-e) antibody number 68e, (lxviii-f) antibody number 68f, (lxix) antibody number 69, (lxx) antibody number 70, (lxx-a) antibody number 70a, (lxx-b) antibody number 7 0b, (lxx-c) Antibody number 70c, (lxx-d) Antibody number 70d, (lxx-e) Antibody number 70e, (lxx-f) Antibody number 70f, (lxxxi) Antibody number 71, (lxxii) Antibody number 72, (lxxxiii) Antibody number 73, (lxxiv) Antibody number 74, (lxxv ) Antibody No. 75, (lxxvi) Antibody No. 76, (lxxvii) Antibody No. 77, (lxxviii) Antibody No. 78, (lxxx) Antibody No. 79, (lxxx) Antibody No. 80, (lxxxi) Antibody No. 81, (lxxxii) Antibody No. 82, (lxxxiii) Antibody No. 83, An anti-human CD28 antibody or antigen-binding antibody fragment according to any one of claims 1 to 3, comprising VH-1 and optionally VL-1, which include the amino acid sequences of CDRH1, CDRH2, and CDRH3 contained in the VH of (lxxxiii-a) antibody number 83a, (lxxxiii-b) antibody number 83b, (lxxxiii-c) antibody number 83c, (lxxxiii-d) antibody number 83d, (lxxxiii-e) antibody number 83e, (lxxxiii-f) antibody number 83f, or (lxxxiv) antibody number 84, respectively.

5. (A) The VH-1 and VL-1, wherein the amino acid sequences of CDRH1-1, CDRH2-1, CDRH3-1, CDRL1-1, CDRL2-1, and CDRL3-1 in the VH-1 and VL-1 are (I) (1) Sequence numbers 112, 114, 116, 122, 124, and 126 respectively, (2) Sequence numbers 2112, 2114, 2116, 2122, 2124, and 2126 respectively, (3) Sequence numbers 2812, 2814, 2816, 2822, 2824, and 2826 respectively, (4) Sequence numbers 4612, 4614, 4616, and 46 22, 4624, and 4626, (5) Sequence numbers 5712, 5714, 5716, 5722, 5724, and 5726 respectively, (6) Sequence numbers 6112, 6114, 6116, 6122, 6124, and 6126 respectively, or (7) Sequence numbers 6812, 6814, 6816, 6822, 6824, and 6826 respectively, and / or (II) (i) Sequence numbers 112, 114, 116, 122, 124, and 126 respectively, (ii) Sequence numbers 212, 214, 216, 222, 224, and 226 respectively, (iii) Sequence numbers 312, 314, 316, 322, 324, and 326 respectively, (iv) Sequence numbers 412, 414, 416, 422, 424, and 426 respectively, (v) Sequence numbers 512, 514, 516, 522, 524, and 526 respectively, (vi) Sequence numbers 612, 614, 616, 622, 624, and 626 respectively, (vii) Sequence numbers 712, 71 4, 716, 722, 724, and 726, (viiii) sequence numbers 812, 814, 816, 822, 824, and 826 respectively, (ix) sequence numbers 912, 914, 916, 922, 924, and 926 respectively, (x) sequence numbers 1012, 1014, 1016, 1022, 1024, and 1026 respectively, (xi) sequence numbers 1112, 1114, 1116, 1122, 1124, and 1126 respectively, (xi) sequence numbers 1212, 1214, 1216, 1222, 1224, and 1226 respectively, (xiiii) sequence numbers 1312, 1 314, 1316, 1322, 1324, and 1326, (xiv) sequence numbers 1412, 1414, 1416, 1422, 1424, and 1426 respectively, (xv) sequence numbers 1512, 1514, 1516, 1522, 1524, and 1526 respectively, (xvi) sequence numbers 1612, 1614, 1616, 1622, 1624, and 1626 respectively, (xvii) sequence numbers 1712, 1714, 1716, 1722, 1724, and 1726 respectively, (xviiii) sequence numbers 1812, 1814, 1816, 1822, 1824, and 18 26, (xix) respective sequence numbers 1912, 1914, 1916, 1922, 1924, and 1926, (xx) respective sequence numbers 2012, 2014, 2016, 2022, 2024, and 2026, (xxi) respective sequence numbers 2112, 2114, 2116, 2122, 2124, and 2126, (xxi-a) respective sequence numbers 2132, 2134, 2136, 2122, 2124, and 2126, (xxi-b) respective sequence numbers 2142, 2144, 2146, 2122, 2124, and 2126, (xxi-c) respective sequence number 2152,2154, 2156, 2122, 2124, and 2126, (xxi-d) sequence numbers 2162, 2164, 2166, 2122, 2124, and 2126 respectively, (xxi-e) sequence numbers 2172, 2174, 2176, 2122, 2124, and 2126 respectively, (xxi-f) sequence numbers 2182, 2184, 2186, 2122, 2124, and 2126 respectively, (xxii) sequence numbers 2212, 2214, 2216, 2222, 2224, and 2226 respectively, (xxiii) sequence numbers 2312, 2314, 2316, 2322, 2324 and 2326, (xxiv) sequence numbers 2412, 2414, 2416, 2422, 2424 and 2426 respectively, (xxv) sequence numbers 2512, 2514, 2516, 2522, 2524 and 2526 respectively, (xxvi) sequence numbers 2612, 2614, 2616, 2622, 2624 and 2626 respectively, (xxvii) sequence numbers 2712, 2714, 2716, 2722, 2724 and 2726 respectively, (xxviiii) sequence numbers 2812, 2814, 2816, 2822, 2824 and 2826 respectively, (xxvii i-a) Sequence numbers 2832, 2834, 2836, 2822, 2824, and 2826 respectively, (xxviiii-b) Sequence numbers 2842, 2844, 2846, 2822, 2824, and 2826 respectively, (xxviiii-c) Sequence numbers 2852, 2854, 2856, 2822, 2824, and 2826 respectively, (xxviiii-d) Sequence numbers 2862, 2864, 2866, 2822, 2824, and 2826 respectively, (xxviiii-e) Sequence numbers 2872, 2874, 2876, 2822, 2824, and 2826 respectively, (xxvi ii-f) Sequence numbers 2882, 2884, 2886, 2822, 2824, and 2826 respectively, (xxix) Sequence numbers 2912, 2914, 2916, 2922, 2924, and 2926 respectively, (xxx) Sequence numbers 3012, 3014, 3016, 3022, 3024, and 3026 respectively, (xxxi) Sequence numbers 3112, 3114, 3116, 3122, 3124, and 3126 respectively, (xxxii) Sequence numbers 3212, 3214, 3216, 3222, 3224, and 3226 respectively, (xxxiiii) Sequence number 3312 respectively,3314, 3316, 3322, 3324, and 3326, (xxxiv) sequence numbers 3412, 3414, 3416, 3422, 3424, and 3426 respectively, (xxxv) sequence numbers 3512, 3514, 3516, 3522, 3524, and 3526 respectively, (xxxvi) sequence numbers 3612, 3614, 3616, 3622, 3624, and 3626 respectively, (xxxvii) sequence numbers 3712, 3714, 3716, 3722, 3724, and 3726 respectively, (xxxviiii) sequence numbers 3812, 3814, 3816, 38 22, 3824, and 3826, (xxxix) sequence numbers 3912, 3914, 3916, 3922, 3924, and 3926 respectively, (xl) sequence numbers 4012, 4014, 4016, 4022, 4024, and 4026 respectively, (xli) sequence numbers 4112, 4114, 4116, 4122, 4124, and 4126 respectively, (xliii) sequence numbers 4212, 4214, 4216, 4222, 4224, and 4226 respectively, (xliiii) sequence numbers 4312, 4314, 4316, 4322, 4324, and 4326 respectively, (xliiv) Sequence numbers 4412, 4414, 4416, 4422, 4424, and 4426 respectively (xlv) Sequence numbers 4512, 4514, 4516, 4522, 4524, and 4526 respectively (xlvi) Sequence numbers 4612, 4614, 4616, 4622, 4624, and 4626 respectively (xlvi-a) Sequence numbers 4632, 4634, 4636, 4622, 4624, and 4626 respectively (xlvi-b) Sequence numbers 4642, 4644, 4646, 4622, 4624, and 4626 respectively (xlvi-c) Sequence numbers 4652, 46 54, 4656, 4622, 4624, and 4626, (xlvi-d) sequence numbers 4662, 4664, 4666, 4622, 4624, and 4626 respectively, (xlvi-e) sequence numbers 4672, 4674, 4676, 4622, 4624, and 4626 respectively, (xlvii) sequence numbers 4712, 4714, 4716, 4722, 4724, and 4726 respectively, (xlviiii) sequence numbers 4812, 4814, 4816, 4822, 4824, and 4826 respectively, (xlix) sequence numbers 4912, 4914, 4916, 4922,4924 and 4926, (l) SEQ ID NOs. 5012, 5014, 5016, 5022, 5024, and 5026 respectively, (li) SEQ ID NOs. 5112, 5114, 5116, 5122, 5124, and 5126 respectively, (lii) SEQ ID NOs. 5212, 5214, 5216, 5222, 5224, and 5226 respectively, (liiii) SEQ ID NOs. 5312, 5314, 5316, 5322, 5324, and 5326 respectively, (liv) SEQ ID NOs. 5412, 5414, 5416, 5422, 5424, and 5426 respectively, (lv) SEQ ID NOs. 551 2, 5514, 5516, 5522, 5524, and 5526, (lvi) sequence numbers 5612, 5614, 5616, 5622, 5624, and 5626 respectively, (lvii) sequence numbers 5712, 5714, 5716, 5722, 5724, and 5726 respectively, (lvii-a) sequence numbers 5732, 5734, 5736, 5722, 5724, and 5726 respectively, (lvii-b) sequence numbers 5742, 5744, 5746, 5722, 5724, and 5726 respectively, (lvii-c) sequence numbers 5752, 5754, 5756, and 572 2, 5724, and 5726, (lvii-d) sequence numbers 5762, 5764, 5766, 5722, 5724, and 5726 respectively, (lvii-e) sequence numbers 5772, 5774, 5776, 5722, 5724, and 5726 respectively, (lvii-f) sequence numbers 5782, 5784, 5786, 5722, 5724, and 5726 respectively, (lviiii) sequence numbers 5812, 5814, 5816, 5822, 5824, and 5826 respectively, (lix) sequence numbers 5912, 5914, 5916, 5922, 5924, and 5926 respectively, (lx) Sequence numbers 6012, 6014, 6016, 6022, 6024, and 6026 respectively, (lxi) Sequence numbers 6112, 6114, 6116, 6122, 6124, and 6126 respectively, (lxi-a) Sequence numbers 6132, 6134, 6136, 6122, 6124, and 6126 respectively, (lxi-b) Sequence numbers 6142, 6144, 6146, 6122, 6124, and 6126 respectively, (lxi-c) Sequence numbers 6152, 6154, 6156, 6122, 6124, and 6126 respectively, (lxi-d) Sequence number 6162,6164, 6166, 6122, 6124, and 6126 (lxi-e) respectively, sequence numbers 6172, 6174, 6176, 6122, 6124, and 6126 (lxi) respectively, sequence numbers 6212, 6214, 6216, 6222, 6224, and 6226 (lxi) respectively, sequence numbers 6312, 6314, 6316, 6322, 6324, and 6326 (lxi) respectively, sequence numbers 6412, 6414, and 6416 6422, 6424, and 6426, (lxv) sequence numbers 6512, 6514, 6516, 6522, 6524, and 6526 respectively, (lxvi) sequence numbers 6612, 6614, 6616, 6622, 6624, and 6626 respectively, (lxvii) sequence numbers 6712, 6714, 6716, 6722, 6724, and 6726 respectively, (lxviiii) sequence numbers 6812, 6814, 6816, 6822, and 6824 respectively , and 6826, (lxviiii-a) sequence numbers 6832, 6834, 6836, 6822, 6824, and 6826 respectively, (lxviiii-b) sequence numbers 6842, 6844, 6846, 6822, 6824, and 6826 respectively, (lxviiii-c) sequence numbers 6852, 6854, 6856, 6822, 6824, and 6826 respectively, (lxviiii-d) sequence numbers 6862, 6864, 6866, 6822, VH-1 and VL-1 include, or consist of, 6824 and 6826, (lxviiii-e) sequence numbers 6872, 6874, 6876, 6822, 6824, and 6826 respectively, (lxviiii-f) sequence numbers 6882, 6884, 6886, 6822, 6824, and 6826 respectively, or (lxix) sequence numbers 6912, 6914, 6916, 6922, 6924, and 6926 respectively, or (B) The VH-1 and optionally the VL-1, wherein the amino acid sequences of the CDRH1-1, CDRH2-1, and CDRH3-1 in the VH-1 are (I) (1) Sequence IDs 7012, 7014, and 7016, respectively, or (2) Sequence IDs 8312, 8314, and 8316, respectively, and / or (II) (i) Sequence numbers 112, 114, and 116 respectively, (ii) Sequence numbers 212, 214, and 216 respectively, (iii) Sequence numbers 312, 314, and 316 respectively, (iv) Sequence numbers 412, 414, and 416 respectively, (v) Sequence numbers 512, 514, and 516 respectively, (vi) Sequence numbers 612, 614, and 616 respectively, (vii) Sequence numbers 712, 714, and 716 respectively, (viiii) Sequence numbers 812, 814, and 816 respectively, (ix) Sequence numbers 912, 914, and 916 respectively, (x) Sequence numbers Numbers 1012, 1014, and 1016, (xi) sequence numbers 1112, 1114, and 1116 respectively, (xi) sequence numbers 1212, 1214, and 1216 respectively, (xiiii) sequence numbers 1312, 1314, and 1316 respectively, (xiv) sequence numbers 1412, 1414, and 1416 respectively, (xv) sequence numbers 1512, 1514, and 1516 respectively, (xvi) sequence numbers 1612, 1614, and 1616 respectively, (xvii) sequence numbers 1712, 1714, and 1716 respectively, (xviiii) sequence number 1812, 1 814 and 1816, (xix) sequence numbers 1912, 1914 and 1916 respectively, (xx) sequence numbers 2012, 2014 and 2016 respectively, (xxi) sequence numbers 2112, 2114 and 2116 respectively, (xxi-a) sequence numbers 2132, 2134 and 2136 respectively, (xxi-b) sequence numbers 2142, 2144 and 2146 respectively, (xxi-c) sequence numbers 2152, 2154 and 2156 respectively, (xxi-d) sequence numbers 2162, 2164 and 2166 respectively, (xxi-e) sequence numbers 2172 and 21 74, and 2176, (xxi-f) sequence numbers 2182, 2184, and 2186 respectively, (xxii) sequence numbers 2212, 2214, and 2216 respectively, (xxiii) sequence numbers 2312, 2314, and 2316 respectively, (xxiv) sequence numbers 2412, 2414, and 2416 respectively, (xxv) sequence numbers 2512, 2514, and 2516 respectively, (xxvi) sequence numbers 2612, 2614, and 2616 respectively, (xxvii) sequence numbers 2712, 2714, and 2716 respectively, (xxviiii) sequence number 2812,2814 and 2816, (xxviiii-a) sequence numbers 2832, 2834, and 2836 respectively, (xxviiii-b) sequence numbers 2842, 2844, and 2846 respectively, (xxviiii-c) sequence numbers 2852, 2854, and 2856 respectively, (xxviiii-d) sequence numbers 2862, 2864, and 2866 respectively, (xxviiii-e) sequence numbers 2872, 2874, and 2876 respectively, (xxviiii-f) sequence numbers 2882, 2884, and 2886 respectively, (xxix) sequence numbers 2912, 2914 respectively, and 2916, (xxx) sequence numbers 3012, 3014, and 3016 respectively, (xxxi) sequence numbers 3112, 3114, and 3116 respectively, (xxxii) sequence numbers 3212, 3214, and 3216 respectively, (xxxiiii) sequence numbers 3312, 3314, and 3316 respectively, (xxxiv) sequence numbers 3412, 3414, and 3416 respectively, (xxxv) sequence numbers 3512, 3514, and 3516 respectively, (xxxvi) sequence numbers 3612, 3614, and 3616 respectively, (xxxvii) sequence number 37 12, 3714, and 3716, (xxxviiii) sequence numbers 3812, 3814, and 3816 respectively, (xxxix) sequence numbers 3912, 3914, and 3916 respectively, (xl) sequence numbers 4012, 4014, and 4016 respectively, (xli) sequence numbers 4112, 4114, and 4116 respectively, (xlii) sequence numbers 4212, 4214, and 4216 respectively, (xliiii) sequence numbers 4312, 4314, and 4316 respectively, (xliv) sequence numbers 4412, 4414, and 4416 respectively, (xlv) sequence number Sequence numbers 4512, 4514, and 4516, (xlvi) sequence numbers 4612, 4614, and 4616 respectively, (xlvi-a) sequence numbers 4632, 4634, and 4636 respectively, (xlvi-b) sequence numbers 4642, 4644, and 4646 respectively, (xlvi-c) sequence numbers 4652, 4654, and 4656 respectively, (xlvi-d) sequence numbers 4662, 4664, and 4666 respectively, (xlvi-e) sequence numbers 4672, 4674, and 4676 respectively, (xlviii) sequence numbers 4712, 4714, and 4716 respectively,(xlviiii) Sequence numbers 4812, 4814, and 4816 respectively, (xlix) Sequence numbers 4912, 4914, and 4916 respectively, (l) Sequence numbers 5012, 5014, and 5016 respectively, (li) Sequence numbers 5112, 5114, and 5116 respectively, (lii) Sequence numbers 5212, 5214, and 5216 respectively, (liiii) Sequence numbers 5312, 5314, and 5316 respectively, (liv) Sequence numbers 5412, 5414, and 5416 respectively, (lv) Sequence numbers 5512, 5514, and 5516 respectively, (lvi) Sequence IDs 5612, 5614, and 5616, (lvii) sequence IDs 5712, 5714, and 5716 respectively, (lvii-a) sequence IDs 5732, 5734, and 5736 respectively, (lvii-b) sequence IDs 5742, 5744, and 5746 respectively, (lvii-c) sequence IDs 5752, 5754, and 5756 respectively, (lvii-d) sequence IDs 5762, 5764, and 5766 respectively, (lvii-e) sequence IDs 5772, 5774, and 5776 respectively, (lvii-f) sequence IDs 5782, 5784, and 5786 respectively, (lviiii) Sequence numbers 5812, 5814, and 5816 respectively, (lix) Sequence numbers 5912, 5914, and 5916 respectively, (lx) Sequence numbers 6012, 6014, and 6016 respectively, (lxi) Sequence numbers 6112, 6114, and 6116 respectively, (lxi-a) Sequence numbers 6132, 6134, and 6136 respectively, (lxi-b) Sequence numbers 6142, 6144, and 6146 respectively, (lxi-c) Sequence numbers 6152, 6154, and 6156 respectively, (lxi-d) Sequence numbers 6162, 6164, and 6166 respectively, ( lxi-e) Sequence codes 6172, 6174, and 6176 respectively, (lxii) Sequence codes 6212, 6214, and 6216 respectively, (lxiii) Sequence codes 6312, 6314, and 6316 respectively, (lxiv) Sequence codes 6412, 6414, and 6416 respectively, (lxv) Sequence codes 6512, 6514, and 6516 respectively, (lxvi) Sequence codes 6612, 6614, and 6616 respectively, (lxvii) Sequence codes 6712, 6714, and 6716 respectively, (lxviiii) Sequence codes 6812, 6814, and 6816 respectively,(lxviiii-a) Sequence numbers 6832, 6834, and 6836 respectively, (lxviiii-b) Sequence numbers 6842, 6844, and 6846 respectively, (lxviiii-c) Sequence numbers 6852, 6854, and 6856 respectively, (lxviiii-d) Sequence numbers 6862, 6864, and 6866 respectively, (lxviiii-e) Sequence numbers 6872, 6874, and 6876 respectively, (lxviiii-f) Sequence numbers 6882, 6884, and 6886 respectively, (lxix) Sequence numbers 6912, 6914, and 6916 respectively, (lxx) Each of these is sequence numbers 7012, 7014, and 7016, (lxx-a) each is sequence numbers 7032, 7034, and 7036, (lxx-b) each is sequence numbers 7042, 7044, and 7046, (lxx-c) each is sequence numbers 7052, 7054, and 7056, (lxx-d) each is sequence numbers 7062, 7064, and 7066, (lxx-e) each is sequence numbers 7072, 7074, and 7076, (lxx-f) each is sequence numbers 7082, 7084, and 7086, (lxxi) each is sequence numbers 7112, 7114, and 7116, ( lxxii) SEQ ID NOs 7212, 7214, and 7216 respectively, (lxxiiii) SEQ ID NOs 7312, 7314, and 7316 respectively, (lxxiv) SEQ ID NOs 7412, 7414, and 7416 respectively, (lxxv) SEQ ID NOs 7512, 7514, and 7516 respectively, (lxxvi) SEQ ID NOs 7612, 7614, and 7616 respectively, (lxxvii) SEQ ID NOs 7712, 7714, and 7716 respectively, (lxxviiii) SEQ ID NOs 7812, 7814, and 7816 respectively, (lxxix) SEQ ID NOs 7912, 79 14, and 7916, (lxxx) sequence numbers 8012, 8014, and 8016 respectively, (lxxxi) sequence numbers 8112, 8114, and 8116 respectively, (lxxxii) sequence numbers 8212, 8214, and 8216 respectively, (lxxxiiii) sequence numbers 8312, 8314, and 8316 respectively, (lxxxiiii-a) sequence numbers 8332, 8334, and 8336 respectively, (lxxxiiii-b) sequence numbers 8342, 8344, and 8346 respectively, (lxxxiiii-c) sequence numbers 8352, 8354, and 8356 respectively,An anti-human CD28 antibody or antigen-binding antibody fragment according to any one of claims 1 to 3, comprising (lxxxiii-d) SEQ ID NOs. 8362, 8364, and 8366, respectively; (lxxxiii-e) SEQ ID NOs. 8372, 8374, and 8376, respectively; (lxxxiii-f) SEQ ID NOs. 8382, 8384, and 8386, respectively; or (lxxxiv) SEQ ID NOs. 8412, 8414, and 8416, respectively, or comprising the above, VH-1 and optionally VL-1.

6. The amino acid sequence of VH-1 includes, or consists of, one of the VH amino acid sequences listed in Table 1A and / or 12A, or a variant thereof having at least about 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity thereto. The amino acid sequence of VL-1 includes, or consists of, one of the VL amino acid sequences listed in Table 1A and / or 12A, or a variant thereof having at least about 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity thereto. The amino acid sequence of VH-1 is encoded by a nucleic acid sequence comprising, and / or, one of the VH coding nucleic acid sequences listed in Table 2A and / or 13A, or a variant thereof having at least about 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity thereto, or a nucleic acid sequence comprising such a sequence. The anti-human CD28 antibody or antigen-binding antibody fragment according to any one of claims 1 to 5, wherein the amino acid sequence of VL-1 comprises any one of the VL-coding nucleic acid sequences listed in Table 2A and / or 13A, or a variant thereof having at least about 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity thereto, or is encoded by a nucleic acid sequence consisting of such a sequence.

7. In (A), the amino acid sequences of VH-1 and VL-1 are, (I) includes, respectively, sequence numbers 110 and 120 in (1), sequence numbers 2110 and 2120 in (2), sequence numbers 2810 and 2820 in (3), sequence numbers 4610 and 4620 in (4), sequence numbers 5710 and 5720 in (5), sequence numbers 6110 and 6120 in (6), or sequence numbers 6810 and 6820 in (7), and / or In (II), the sequence numbers 110 and 120 in (i), 210 and 220 in (ii), 310 and 320 in (iii), 410 and 420 in (iv), 510 and 520 in (v), 610 and 620 in (vi), 710 and 720 in (vii), 810 and 820 in (viiii), 910 and 920 in (ix), and the sequence numbers in (x) Numbers 1010 and 1020, sequence numbers 1110 and 1120 in (xi) respectively, sequence numbers 1210 and 1220 in (xi) respectively, sequence numbers 1310 and 1320 in (iii) respectively, sequence numbers 1410 and 1420 in (xiv) respectively, sequence numbers 1510 and 1520 in (xv) respectively, sequence numbers 1610 and 1620 in (xvi) respectively, sequence numbers 1710 and 1720 in (xvii) respectively, sequence numbers 1810 and 1820 in (xviiii) respectively, in (xix) These are sequence numbers 1910 and 1920 respectively, sequence numbers 2010 and 2020 in (xx) respectively, sequence numbers 2110 and 2120 in (xxi) respectively, sequence numbers 2130 and 2120 in (xxi-a) respectively, sequence numbers 2140 and 2120 in (xxi-b) respectively, sequence numbers 2150 and 2120 in (xxi-c) respectively, sequence numbers 2160 and 2120 in (xxi-d) respectively, sequence numbers 2170 and 2120 in (xxi-e) respectively, and sequence number 218 in (xxi-f) respectively. 0 and 2120, sequence numbers 2210 and 2220 in (xxii), sequence numbers 2310 and 2320 in (xxiiii), sequence numbers 2410 and 2420 in (xxiv), sequence numbers 2510 and 2520 in (xxv), sequence numbers 2610 and 2620 in (xxvi), sequence numbers 2710 and 2720 in (xxvii), sequence numbers 2810 and 2820 in (xxviiiii), sequence numbers 2830 and 2820 in (xxviiii-a),SEQ ID NOs 2840 and 2820 in (xxviiii-b), 2850 and 2820 in (xxviiii-c), 2860 and 2820 in (xxviiii-d), 2870 and 2820 in (xxviiii-e), 2880 and 2820 in (xxviiii-f), 2910 and 2920 in (xxix), 3010 and 3020 in (xxx), and 3110 and 31 in (xxxi). 20, SEQ ID NOs 3210 and 3220 in (xxxii), SEQ ID NOs 3310 and 3320 in (xxxiiii), SEQ ID NOs 3410 and 3420 in (xxxiv), SEQ ID NOs 3510 and 3520 in (xxxv), SEQ ID NOs 3610 and 3620 in (xxxvi), SEQ ID NOs 3710 and 3720 in (xxxvii), SEQ ID NOs 3810 and 3820 in (xxxviiiii), SEQ ID NOs 3910 and 3920 in (xxxix), (x (l) Sequence numbers 4010 and 4020 respectively, (xli) sequence numbers 4110 and 4120 respectively, (xliii) sequence numbers 4210 and 4220 respectively, (xliiii) sequence numbers 4310 and 4320 respectively, (xliiv) sequence numbers 4410 and 4420 respectively, (xlv) sequence numbers 4510 and 4520 respectively, (xlvi) sequence numbers 4610 and 4620 respectively, (xlvvi-a) sequence numbers 4630 and 4620 respectively, (xlvvi-b) sequence numbers Sequence numbers 4640 and 4620, sequence numbers 4650 and 4620 in (xlvi-c) respectively, sequence numbers 4660 and 4620 in (xlvi-d) respectively, sequence numbers 4670 and 4620 in (xlvi-e) respectively, sequence numbers 4710 and 4720 in (xlvii) respectively, sequence numbers 4810 and 4820 in (xlviiii) respectively, sequence numbers 4910 and 4920 in (xlix) respectively, sequence numbers 5010 and 5020 in (l) respectively, sequence numbers 5110 and 5120 in (li) respectively,Sequence numbers 5210 and 5220 in (lii), sequence numbers 5310 and 5320 in (liiii), sequence numbers 5410 and 5420 in (lv), sequence numbers 5510 and 5520 in (lv), sequence numbers 5610 and 5620 in (lvi), sequence numbers 5710 and 5720 in (lvii), sequence numbers 5730 and 5720 in (lvii-a), sequence numbers 5740 and 5720 in (lvii-b), and in (lvii-c) Sequence IDs 5750 and 5720, 5760 and 5720 in (lvii-d) respectively, 5770 and 5720 in (lvii-e) respectively, 5780 and 5720 in (lvii-f) respectively, 5810 and 5820 in (lviiii) respectively, 5910 and 5920 in (lix) respectively, 6010 and 6020 in (lx) respectively, 6110 and 6120 in (lxi) respectively, and 6130 and 6 in (lxi-a) respectively. 120, (lxi-b) with sequence numbers 6140 and 6120 respectively, (lxi-c) with sequence numbers 6150 and 6120 respectively, (lxi-d) with sequence numbers 6160 and 6120 respectively, (lxi-e) with sequence numbers 6170 and 6120 respectively, (lxi-e) with sequence numbers 6210 and 6220 respectively, (lxiii) with sequence numbers 6310 and 6320 respectively, (lxiiii) with sequence numbers 6410 and 6420 respectively, (lxiv) with sequence numbers 6510 and 6520 respectively, (lxv) with sequence numbers 6510 and 6520 respectively, (lxvi) The respective sequence numbers 6610 and 6620 in (lxvii), sequence numbers 6710 and 6720 in (lxvii), sequence numbers 6810 and 6820 in (lxviiiii), sequence numbers 6830 and 6820 in (lxviiii-a), sequence numbers 6840 and 6820 in (lxviiiii-b), sequence numbers 6850 and 6820 in (lxviiiii-c), sequence numbers 6860 and 6820 in (lxviiiii-d), and sequence numbers 6870 and 6820 in (lxviiiii-e).The sequence identity of sequence numbers 6880 and 6820 in (lxviiii-f), or sequence numbers 6910 and 6920 in (lxix), respectively, is at least about 80%, at least about 85%, at least about 90%, at least about 91%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, or at least or at least about 99%, or, (B) The amino acid sequence of VH-1 is (I) in (1) Sequence ID 7010, or in (2) Sequence ID 8310, and / or (II) includes, in (i) sequence number 110, in (ii) sequence number 210, in (iii) sequence number 310, in (iv) sequence number 410, in (v) sequence number 510, in (vi) sequence number 610, in (vii) sequence number 710, in (viiii) sequence number 810, in (ix) sequence number 910, in (x) sequence number 1010, in (xi) sequence number 1110, in (xi) sequence number 1210, in (xiiii) sequence number 1310, in (xiv) sequence number 1410, and in (xv) sequence number Column number 1510, SEQ ID NO: 1610 in (xvi), SEQ ID NO: 1710 in (xvii), SEQ ID NO: 1810 in (xviiii), SEQ ID NO: 1910 in (xix), SEQ ID NO: 2010 in (xx), SEQ ID NO: 2110 in (xxi), SEQ ID NO: 2130 in (xxi-a), SEQ ID NO: 2140 in (xx-b), SEQ ID NO: 2150 in (xxi-c), SEQ ID NO: 2160 in (xxi-d), SEQ ID NO: 2170 in (xxi-e), SEQ ID NO: 2180 in (xxi-f), Array in (xxii) Number 2210, SEQ ID NO: 2310 in (xxiiii), SEQ ID NO: 2410 in (xxiv), SEQ ID NO: 2510 in (xxv), SEQ ID NO: 2610 in (xxvi), SEQ ID NO: 2710 in (xxvii), SEQ ID NO: 2810 in (xxviiiii), SEQ ID NO: 2830 in (xxviiiii-a), SEQ ID NO: 2840 in (xxviiiii-b), SEQ ID NO: 2850 in (xxviiiii-c), SEQ ID NO: 2860 in (xxviiiii-d), SEQ ID NO: 2870 in (xxviiiii-e), (xxviiiii-f) SEQ ID NO: 2880 in (xxxx), SEQ ID NO: 2910 in (xxxx), SEQ ID NO: 3010 in (xxxi), SEQ ID NO: 3110 in (xxxii), SEQ ID NO: 3210 in (xxxiiii), SEQ ID NO: 3310 in (xxxiv), SEQ ID NO: 3410 in (xxxv), SEQ ID NO: 3510 in (xxxvi), SEQ ID NO: 3610 in (xxxvii), SEQ ID NO: 3710 in (xxxviiiii), SEQ ID NO: 3810 in (xxxix), SEQ ID NO: 3910 in (xxxix), SEQ ID NO: 4010 in (xl)SEQ ID NOs in (xli) 4110, (xliii) 4210, (xliiii) 4310, (xliv) 4410, (xlv) 4510, (xlvi) 4610, (xlvi-a) 4630, (xlvi-b) 4640, (xlvi-c) 4650, (xlvi-d) 4660, (xlvi-e) 4670, (xlviii) 4710, (xlviiii) Sequence ID 4810, Sequence ID 4910 in (xlix), Sequence ID 5010 in (l), Sequence ID 5110 in (li), Sequence ID 5210 in (liii), Sequence ID 5310 in (liiii), Sequence ID 5410 in (liv), Sequence ID 5510 in (lv), Sequence ID 5610 in (lvi), Sequence ID 5710 in (lviii), Sequence ID 5730 in (lviii-a), Sequence ID 5740 in (lviii-b), Sequence ID 5750 in (lviii-c), Sequence ID 5750 in (lviii-d) Column number 5760, SEQ ID NO: 5770 in (lvii-e), SEQ ID NO: 5780 in (lvii-f), SEQ ID NO: 5810 in (lviiiii), SEQ ID NO: 5910 in (lix), SEQ ID NO: 6010 in (lx), SEQ ID NO: 6110 in (lxi), SEQ ID NO: 6130 in (lxi-a), SEQ ID NO: 6140 in (lxi-b), SEQ ID NO: 6150 in (lxi-c), SEQ ID NO: 6160 in (lxi-d), SEQ ID NO: 6170 in (lxii-e), SEQ ID NO: 6210 in (lxii), (lxiiiii SEQ ID NO: 6310 in (lxiv), SEQ ID NO: 6410 in (lxiv), SEQ ID NO: 6510 in (lxv), SEQ ID NO: 6610 in (lxvi), SEQ ID NO: 6710 in (lxviii), SEQ ID NO: 6810 in (lxviiiii-a), SEQ ID NO: 6830 in (lxviiiii-b), SEQ ID NO: 6840 in (lxviiiii-c), SEQ ID NO: 6860 in (lxviiiii-d), SEQ ID NO: 6870 in (lxviiiii-e), SEQ ID NO: 6880 in (lxviiiii-f)SEQ ID NO: 6910 in (lxix), SEQ ID NO: 7010 in (lxx), SEQ ID NO: 7030 in (lxx-a), SEQ ID NO: 7040 in (lxx-b), SEQ ID NO: 7050 in (lxx-c), SEQ ID NO: 7060 in (lxx-d), SEQ ID NO: 7070 in (lxx-e), SEQ ID NO: 7080 in (lxxi), SEQ ID NO: 7110 in (lxxii), SEQ ID NO: 7 210, SEQ ID NO: 7310 in (lxxiiii), SEQ ID NO: 7410 in (lxxiv), SEQ ID NO: 7510 in (lxxv), SEQ ID NO: 7610 in (lxxvii), SEQ ID NO: 7710 in (lxxvii), SEQ ID NO: 7810 in (lxxviiiii), or SEQ ID NO: 7910 in (lxxix), SEQ ID NO: 8010 in (lxxxx), SEQ ID NO: 8110 in (lxxxi), (l SEQ ID NO: 8210 in (xxxii), SEQ ID NO: 8310 in (lxxxiiii), SEQ ID NO: 8330 in (lxxxiiii-a), SEQ ID NO: 8340 in (lxxxiiii-b), SEQ ID NO: 8350 in (lxxxiiii-c), SEQ ID NO: 8360 in (lxxxiiii-d), SEQ ID NO: 8370 in (lxxxiiii-e), SEQ ID NO: 8380 in (lxxxiiii-f), or (lx The anti-human CD28 antibody or antigen-binding antibody fragment according to claim 4 or 5, having at least about 80%, at least about 85%, at least about 90%, at least about 91%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, or at least or at least about 99% sequence identity with respect to sequence number 8410 in xxiv).

8. In (A), the amino acid sequences of VH-1 and VL-1 are, (I) includes, respectively, sequence numbers 110 and 120 in (1), sequence numbers 2110 and 2120 in (2), sequence numbers 2810 and 2820 in (3), sequence numbers 4610 and 4620 in (4), sequence numbers 5710 and 5720 in (5), sequence numbers 6110 and 6120 in (6), or sequence numbers 6810 and 6820 in (7), and / or In (II), the sequence numbers 110 and 120 in (i), 210 and 220 in (ii), 310 and 320 in (iii), 410 and 420 in (iv), 510 and 520 in (v), 610 and 620 in (vi), 710 and 720 in (vii), 810 and 820 in (viiii), 910 and 920 in (ix), and the sequence numbers in (x) Numbers 1010 and 1020, sequence numbers 1110 and 1120 in (xi) respectively, sequence numbers 1210 and 1220 in (xi) respectively, sequence numbers 1310 and 1320 in (iii) respectively, sequence numbers 1410 and 1420 in (xiv) respectively, sequence numbers 1510 and 1520 in (xv) respectively, sequence numbers 1610 and 1620 in (xvi) respectively, sequence numbers 1710 and 1720 in (xvii) respectively, sequence numbers 1810 and 1820 in (xviiii) respectively, in (xix) These are sequence numbers 1910 and 1920 respectively, sequence numbers 2010 and 2020 in (xx) respectively, sequence numbers 2110 and 2120 in (xxi) respectively, sequence numbers 2130 and 2120 in (xxi-a) respectively, sequence numbers 2140 and 2120 in (xxi-b) respectively, sequence numbers 2150 and 2120 in (xxi-c) respectively, sequence numbers 2160 and 2120 in (xxi-d) respectively, sequence numbers 2170 and 2120 in (xxi-e) respectively, and sequence number 218 in (xxi-f) respectively. 0 and 2120, sequence numbers 2210 and 2220 in (xxii), sequence numbers 2310 and 2320 in (xxiiii), sequence numbers 2410 and 2420 in (xxiv), sequence numbers 2510 and 2520 in (xxv), sequence numbers 2610 and 2620 in (xxvi), sequence numbers 2710 and 2720 in (xxvii), sequence numbers 2810 and 2820 in (xxviiiii), sequence numbers 2830 and 2820 in (xxviiii-a),SEQ ID NOs 2840 and 2820 in (xxviiii-b), 2850 and 2820 in (xxviiii-c), 2860 and 2820 in (xxviiii-d), 2870 and 2820 in (xxviiii-e), 2880 and 2820 in (xxviiii-f), 2910 and 2920 in (xxix), 3010 and 3020 in (xxx), and 3110 and 31 in (xxxi). 20, SEQ ID NOs 3210 and 3220 in (xxxii), SEQ ID NOs 3310 and 3320 in (xxxiiii), SEQ ID NOs 3410 and 3420 in (xxxiv), SEQ ID NOs 3510 and 3520 in (xxxv), SEQ ID NOs 3610 and 3620 in (xxxvi), SEQ ID NOs 3710 and 3720 in (xxxvii), SEQ ID NOs 3810 and 3820 in (xxxviiiii), SEQ ID NOs 3910 and 3920 in (xxxix), (x (l) Sequence numbers 4010 and 4020 respectively, (xli) sequence numbers 4110 and 4120 respectively, (xliii) sequence numbers 4210 and 4220 respectively, (xliiii) sequence numbers 4310 and 4320 respectively, (xliiv) sequence numbers 4410 and 4420 respectively, (xlv) sequence numbers 4510 and 4520 respectively, (xlvi) sequence numbers 4610 and 4620 respectively, (xlvvi-a) sequence numbers 4630 and 4620 respectively, (xlvvi-b) sequence numbers Sequence numbers 4640 and 4620, sequence numbers 4650 and 4620 in (xlvi-c) respectively, sequence numbers 4660 and 4620 in (xlvi-d) respectively, sequence numbers 4670 and 4620 in (xlvi-e) respectively, sequence numbers 4710 and 4720 in (xlvii) respectively, sequence numbers 4810 and 4820 in (xlviiii) respectively, sequence numbers 4910 and 4920 in (xlix) respectively, sequence numbers 5010 and 5020 in (l) respectively, sequence numbers 5110 and 5120 in (li) respectively,Sequence numbers 5210 and 5220 in (lii), sequence numbers 5310 and 5320 in (liiii), sequence numbers 5410 and 5420 in (lv), sequence numbers 5510 and 5520 in (lv), sequence numbers 5610 and 5620 in (lvi), sequence numbers 5710 and 5720 in (lvii), sequence numbers 5730 and 5720 in (lvii-a), sequence numbers 5740 and 5720 in (lvii-b), and in (lvii-c) Sequence IDs 5750 and 5720, 5760 and 5720 in (lvii-d) respectively, 5770 and 5720 in (lvii-e) respectively, 5780 and 5720 in (lvii-f) respectively, 5810 and 5820 in (lviiii) respectively, 5910 and 5920 in (lix) respectively, 6010 and 6020 in (lx) respectively, 6110 and 6120 in (lxi) respectively, and 6130 and 6 in (lxi-a) respectively. 120, (lxi-b) with sequence numbers 6140 and 6120 respectively, (lxi-c) with sequence numbers 6150 and 6120 respectively, (lxi-d) with sequence numbers 6160 and 6120 respectively, (lxi-e) with sequence numbers 6170 and 6120 respectively, (lxi-e) with sequence numbers 6210 and 6220 respectively, (lxiii) with sequence numbers 6310 and 6320 respectively, (lxiiii) with sequence numbers 6410 and 6420 respectively, (lxiv) with sequence numbers 6510 and 6520 respectively, (lxv) with sequence numbers 6510 and 6520 respectively, (lxvi) The respective sequence numbers 6610 and 6620 in (lxvii), sequence numbers 6710 and 6720 in (lxvii), sequence numbers 6810 and 6820 in (lxviiiii), sequence numbers 6830 and 6820 in (lxviiii-a), sequence numbers 6840 and 6820 in (lxviiiii-b), sequence numbers 6850 and 6820 in (lxviiiii-c), sequence numbers 6860 and 6820 in (lxviiiii-d), and sequence numbers 6870 and 6820 in (lxviiiii-e).(lxviiii-f) contains or consists of sequence numbers 6880 and 6820, respectively, or (lxix), or sequence numbers 6910 and 6920, respectively, or (B) The amino acid sequence of VH-1 is (I) in (1) Sequence ID 7010, or in (2) Sequence ID 8310, and / or (II) includes, in (i) sequence number 110, in (ii) sequence number 210, in (iii) sequence number 310, in (iv) sequence number 410, in (v) sequence number 510, in (vi) sequence number 610, in (vii) sequence number 710, in (viiii) sequence number 810, in (ix) sequence number 910, in (x) sequence number 1010, in (xi) sequence number 1110, in (xi) sequence number 1210, in (xiiii) sequence number 1310, in (xiv) sequence number 1410, and in (xv) sequence number Column number 1510, SEQ ID NO: 1610 in (xvi), SEQ ID NO: 1710 in (xvii), SEQ ID NO: 1810 in (xviiii), SEQ ID NO: 1910 in (xix), SEQ ID NO: 2010 in (xx), SEQ ID NO: 2110 in (xxi), SEQ ID NO: 2130 in (xxi-a), SEQ ID NO: 2140 in (xx-b), SEQ ID NO: 2150 in (xxi-c), SEQ ID NO: 2160 in (xxi-d), SEQ ID NO: 2170 in (xxi-e), SEQ ID NO: 2180 in (xxi-f), Array in (xxii) Number 2210, SEQ ID NO: 2310 in (xxiiii), SEQ ID NO: 2410 in (xxiv), SEQ ID NO: 2510 in (xxv), SEQ ID NO: 2610 in (xxvi), SEQ ID NO: 2710 in (xxvii), SEQ ID NO: 2810 in (xxviiiii), SEQ ID NO: 2830 in (xxviiiii-a), SEQ ID NO: 2840 in (xxviiiii-b), SEQ ID NO: 2850 in (xxviiiii-c), SEQ ID NO: 2860 in (xxviiiii-d), SEQ ID NO: 2870 in (xxviiiii-e), (xxviiiii-f) SEQ ID NO: 2880 in (xxxx), SEQ ID NO: 2910 in (xxxx), SEQ ID NO: 3010 in (xxxi), SEQ ID NO: 3110 in (xxxii), SEQ ID NO: 3210 in (xxxiiii), SEQ ID NO: 3310 in (xxxiv), SEQ ID NO: 3410 in (xxxv), SEQ ID NO: 3510 in (xxxvi), SEQ ID NO: 3610 in (xxxvii), SEQ ID NO: 3710 in (xxxviiiii), SEQ ID NO: 3810 in (xxxix), SEQ ID NO: 3910 in (xxxix), SEQ ID NO: 4010 in (xl)SEQ ID NOs in (xli) 4110, (xliii) 4210, (xliiii) 4310, (xliv) 4410, (xlv) 4510, (xlvi) 4610, (xlvi-a) 4630, (xlvi-b) 4640, (xlvi-c) 4650, (xlvi-d) 4660, (xlvi-e) 4670, (xlviii) 4710, (xlviiii) Sequence ID 4810, Sequence ID 4910 in (xlix), Sequence ID 5010 in (l), Sequence ID 5110 in (li), Sequence ID 5210 in (liii), Sequence ID 5310 in (liiii), Sequence ID 5410 in (liv), Sequence ID 5510 in (lv), Sequence ID 5610 in (lvi), Sequence ID 5710 in (lviii), Sequence ID 5730 in (lviii-a), Sequence ID 5740 in (lviii-b), Sequence ID 5750 in (lviii-c), Sequence ID 5750 in (lviii-d) Column number 5760, SEQ ID NO: 5770 in (lvii-e), SEQ ID NO: 5780 in (lvii-f), SEQ ID NO: 5810 in (lviiiii), SEQ ID NO: 5910 in (lix), SEQ ID NO: 6010 in (lx), SEQ ID NO: 6110 in (lxi), SEQ ID NO: 6130 in (lxi-a), SEQ ID NO: 6140 in (lxi-b), SEQ ID NO: 6150 in (lxi-c), SEQ ID NO: 6160 in (lxi-d), SEQ ID NO: 6170 in (lxii-e), SEQ ID NO: 6210 in (lxii), (lxiiiii SEQ ID NO: 6310 in (lxiv), SEQ ID NO: 6410 in (lxiv), SEQ ID NO: 6510 in (lxv), SEQ ID NO: 6610 in (lxvi), SEQ ID NO: 6710 in (lxviii), SEQ ID NO: 6810 in (lxviiiii-a), SEQ ID NO: 6830 in (lxviiiii-b), SEQ ID NO: 6840 in (lxviiiii-c), SEQ ID NO: 6860 in (lxviiiii-d), SEQ ID NO: 6870 in (lxviiiii-e), SEQ ID NO: 6880 in (lxviiiii-f)SEQ ID NO: 6910 in (lxix), SEQ ID NO: 7010 in (lxx), SEQ ID NO: 7030 in (lxx-a), SEQ ID NO: 7040 in (lxx-b), SEQ ID NO: 7050 in (lxx-c), SEQ ID NO: 7060 in (lxx-d), SEQ ID NO: 7070 in (lxx-e), SEQ ID NO: 7080 in (lxx-f), SEQ ID NO: 7110 in (lxxi), SEQ ID NO: 7210 in (lxxii), SEQ ID NO: 7310 in (lxxiiii), SEQ ID NO: 7410 in (lxxiv), SEQ ID NO: 7510 in (lxxv), SEQ ID NO: 7610 in (lxxvii), SEQ ID NO: 7710 in (lxxviiiii), SEQ ID NO: 7810 in (lxxviiiii), or (l An anti-human CD28 antibody or antigen-binding antibody fragment according to any one of claims 4, 5, or 7, comprising or consisting of: SEQ ID NO: 7910 in (xxxx), SEQ ID NO: 8010 in (lxxxx), SEQ ID NO: 8110 in (lxxxxi), SEQ ID NO: 8210 in (lxxxiiii), SEQ ID NO: 8310 in (lxxxiiiiii-a), SEQ ID NO: 8330 in (lxxxiiiiii-b), SEQ ID NO: 8340 in (lxxxiiiiii-c), SEQ ID NO: 8350 in (lxxxiiiiii-d), SEQ ID NO: 8360 in (lxxxiiiiii-e), SEQ ID NO: 8370 in (lxxxiiiiii-f), or SEQ ID NO: 8380 in (lxxxiv).

9. (a) Immunoglobulin (Ig) format or its half-antibody variant, optionally IgG, IgA, IgE, IgD, or IgM format, further optionally IgG1, IgG2, IgG3, or IgG4 format, (b) Antibody fragment antigen-binding region (Fab) format, Fab' format, F(ab') ２ Format, F(ab') ３ Format, and / or variable fragment (Fv) format, (c) Single-stranded fragment variable region (scFv) format, tandem scFv format, diabody format, triabody format, tetrabody format, scFv-Fc format, scFv-CH format, minibody format, scFv-zipper format, diabody-Fc format, diabody-CH format, any of the aforementioned half-antibody variants, and / or single-stranded Fab (scFab) format, (d) Heavy chain-only antibody (HCAb) format, nanobody-Fc format, nanobody-CH format, single-chain nanobody-CH format, camel Ig format, and / or IgNAR format, or any single-chain variant of any of the above, and / or (e) an anti-human CD28 antibody or antigen-binding antibody fragment according to any one of claims 1 to 8, comprising a single-domain antibody (sdAb) format, a nanobody format, or a tandem nanobody format.

10. The VH-1 and VL-1, wherein the anti-human CD28 antibody or antigen-binding antibody fragment is (a) A heavy chain containing VH-1 and a light chain containing VL-1, wherein optionally the antibody or antigen-binding antibody fragment is (a-1) Consists of the heavy chain and light chain, (a-2) an Ig molecule containing two heavy chains and two light chains, or a polymer of the Ig molecule, and / or (a-3) A heavy chain containing VH-1 and a light chain containing VL-1, comprising or consisting of IgG, IgA, IgE, IgD, or IgM, optionally IgG1, IgG2, IgG3, or IgG4, and / or (b) Fab including VH-1 and VL-1, Fab' including VH-1 and VL-1, F(ab') including VH-1 and VL-1 ２ F(ab') including the VH-1 and the VL-1 ３ , and / or Fv including the VH-1 and the VL-1, and / or (c) scFv including VH-1 and VL-1, tandem scFv including VH-1 and VL-1, diamond body including VH-1 and VL-1, tria body including VH-1 and VL-1, tetra body including VH-1 and VL-1, scFv-Fc including VH-1 and VL-1, scFv-CH including VH-1 and VL-1, mini body including VH-1 and VL-1, scFv-zipper including VH-1 and VL-1, diamond body-Fc including VH-1 and VL-1, diamond body-CH including VH-1 and VL-1, and / or scFab including VH-1 and VL-1, or VH-1 and VL-1, or The VH-1, wherein the anti-human CD28 antibody or antigen-binding antibody fragment is (d) HCAb containing VH-1, nanobody-Fc containing VH-1, nanobody-CH containing VH-1, camel Ig containing VH-1, IgNAR containing VH-1, and / or any single-stranded variant of the above, and / or (e) an anti-human CD28 antibody or antigen-binding antibody fragment according to any one of claims 1 to 9, comprising VH-1, an sdAb comprising VH-1, a nanobody comprising VH-1, and / or a tandem nanobody comprising VH-1, or comprising VH-1 therein.

11. The following features: (a) binds to mouse CD28 and / or cynomolgus monkey CD28, (b) At physiological pH or pH 7.4, measured by biolayer interferometry (BLI), and further optionally as performed in Examples 3 and / or 12, in concentrations less than approximately 1 μM, less than approximately 500 nM, less than approximately 200 nM, less than approximately 100 nM, less than approximately 50 nM, less than approximately 20 nM, less than approximately 10 nM, less than approximately 5 nM, less than approximately 2 nM, less than approximately 1 nM, less than approximately 500 pM, approximately 1 μM, approximately 500 nM, approximately 200 nM, about 100 nM, about 50 nM, about 20 nM, about 10 nM, about 5 nM, about 2 nM, about 1 nM, about 500 pM, about 200 pM, about 100 nM to 1 nM, about 50 nM to 1 nM, about 20 nM to 1 nM, about 10 nM to K of 1 nM, about 5 nM to 1 nM, about 2 nM to 1 nM, about 10 nM to 500 pM, about 5 nM to 500 pM, about 2 nM to 500 pM, about 1 nM to 500 pM, about 1 nM to 200 pM, or about 500 pM to about 200 pM. Ｄ It binds to human CD28. (c) K at an acidic pH or pH 6.0, with concentrations of less than approximately 1 μM, less than approximately 500 nM, less than approximately 200 nM, less than approximately 100 nM, less than approximately 50 nM, less than approximately 20 nM, less than approximately 10 nM, less than approximately 5 nM, less than approximately 2 nM, less than approximately 1 nM, approximately 1 μM, approximately 500 nM, approximately 200 nM, approximately 100 nM, approximately 50 nM, approximately 20 nM, approximately 10 nM, approximately 5 nM, approximately 2 nM, or approximately 1 nM. Ｄ It binds to human CD28. (d) As optionally measured by BLI, and further optionally carried out in Example 3, at acidic pH or pH 6.0 compared to physiological pH or pH 7.4, optionally about 1.5 times, about 2 times, about 3 times, about 4 times, about 5 times, about 6 times, about 7 times, about 8 times, about 9 times, about 10 times, about 12 times, about 15 times, about 20 times, about 25 times, about 30 times, about 35 times, about 40 times, about 45 times, about 50 times, about 60 times, about 70 times, about 80 times, about 90 times, about 100 times, about 200 times, about 300 times, about 400 times, about 500 times, about 600 times, about 700 times, about 800 times, about 90 times, or about 1000 times, or at least that much lower K at acidic pH or pH 6.

0. Ｄ It binds to human CD28. (e) To be measured by BLI, and further optionally as performed in Example 3, a substance that binds to human CD28 at an acidic pH or pH 6.0 but does not bind to human CD28 at a physiological pH or pH 7.4, (f) K is not bound to mouse or murine CD28, or is measured by BLI, and is further optionally carried out in Examples 3 and / or 12, or is greater than 10 nM, greater than 20 nM, greater than 50 nM, greater than 100 nM, greater than 200 nM, greater than 500 nM, greater than 1 μM, greater than 10 nM, greater than 20 nM, greater than 500 nM, greater than 1 μM, greater than 10 nM, greater than 20 nM, greater than 50 nM, greater than 100 nM, greater than 200 nM, greater than 500 nM, or greater than 1 μM. Ｄ It binds to mouse or mouse family CD28, (g)Optionally, as measured by BLI, and further optionally as performed in Example 3 and / or 12, does not bind to the human CD28 monomer or binds to the human CD28 monomer with a K of greater than about 1 nM, greater than about 10 nM, greater than about 20 nM, greater than about 50 nM, greater than about 100 nM, greater than about 200 nM, greater than about 500 nM, greater than about 1 μM, about 1 nM, about 10 nM, about 20 nM, about 50 nM, about 100 nM, about 200 nM, about 500 nM, or about 1 μM Ｄ that binds to the human CD28 monomer, (h) As can be optionally measured by flow cytometry, and further optionally based on the median fluorescence intensity and / or normalized cell binding values, and further optionally as performed in Examples 5 and / or 13, CTL-77428 (TheraMab IgG Hu5.11 Defines Bin 1), CTL-77431 (OSE IgG HCD28.3 Defines Bin 2), CTL-77432 (Astellas IgG FK734), CTL-77435 (Sanofi IgG CD28sup), CTL-77436 (Roche IgG Compared to one or more of SA28_v15), and / or CTL-77440 (Inhibirx HCAb INRX28), it binds more efficiently to human CD28-expressing cells, optionally to Jurkat cells and / or human CD28-CHO cells. (i) A polyspecific reagent (PSR) score of < 0.1 (clean), 0.10 ≤ score < 0.33 (low), or 0.33 ≤ score < 0.66 (medium), or 0.00, as measured by a PSR assay, as optionally performed in Examples 6 and / or 14. (j) As measured by hydrophobic interaction chromatography (HIC), the HIC retention time (RT) is optionally performed in Examples 6 and / or 14, with RT < 9.5 min, RT < 10.0 min, or RT < 10.5 min (clean or low), or 10.5 min ≤ RT < 11.5 min (medium), (k) exhibiting a melting temperature (Tm) of less than about 45°C, less than about 50°C, less than about 55°C, less than about 60°C, less than about 65°C, less than about 70°C, less than about 75°C, less than about 80°C, less than about 85°C, greater than about 45°C, greater than about 50°C, greater than about 55°C, greater than about 60°C, greater than about 65°C, greater than about 70°C, greater than about 75°C, greater than about 80°C, greater than 85°C, about 45°C, about 50°C, about 55°C, about 60°C, about 65°C, about 70°C, about 75°C, about 80°C, or about 85°C, and / or (l)(l-1) an increase in CD69 expression of approximately 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 100%, 150%, 200%, 250%, 300%, 350%, 400%, 450%, or 500%, based on an increase in mean fluorescence intensity (MFI), as measured by flow cytometry. (l-2) Selectively measure by an immunoassay, such as by an enzyme-linked immunosorbent assay (ELISA), approximately 1.5 times, 2 times, 3 times, 4 times, 5 times, 6 times, 7 times, 8 times, 9 times, 10 times, 12 times, 15 times, 20 times, 25 times, 30 times, 35 times, 40 times, 45 times, or 50 times, or at least that much. Therefore, an optional increase in IL-2 emissions of approximately 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 100%, 150%, 200%, 250%, 300%, 350%, 400%, 450%, or 500%, or (l-3) Optionally, during T cell incubation with anti-human CD28 antibody or antigen-binding antibody fragment, and optionally with anti-CD3 antibody, as measured using CD28 Bioassay (Promega, TM633), The anti-human CD28 antibody or antigen-binding antibody fragment according to any one of claims 1 to 10, comprising one or more of the following: the T cells can be stimulated as determined by at least one of the following, further optionally, an increase in transcriptional activation, as performed in Example 7, compared optionally with the incubation of the T cells without the anti-human CD28 antibody or antigen-binding antibody fragment, with or without the anti-CD3 antibody.

12. A multispecific antibody, (1) A first antigen-binding region (ABR-1) that binds to human CD28, wherein the ABR-1 comprises an anti-human CD28 antibody or antigen-binding antibody fragment according to any one of claims 1 to 11, (2) A second antigen-binding region (ABR-2) that binds to a second antigen, wherein the ABR-2 is optionally, A second heavy chain variable domain (VH-2) comprising a second heavy chain complementarity determining region (CDR) 1 (CDRH1-2), a second heavy chain CDR2 (CDRH2-2), and a second heavy chain CDR3 (CDRH3-2), and / or A second antigen-binding region (ABR-2) includes a second light chain variable domain (VL-2) comprising a second light chain CDR1 (CDRL1-2), a second light chain CDR2 (CDRL2-2), and a second light chain CDR3 (CDRL3-2), The second antigen is optionally the same as or different from human CD28. A multispecific antibody in which, optionally, the multispecific antibody is bispecific, triplicate, or quadruplicate.

13. The second antigen described above is (a) Human differentiation cluster 3 (CD3), (b) cancer antigens, optionally tumor-specific antigens (TSAs) or tumor-associated antigens (TAAs), (c) Human CD28, (d) Any one of the antigens selected from those listed in Table 3, and / or (c) The multispecific antibody according to claim 12, which is any one of the cancer antigens selected from those listed in Table 3, optionally any one of the TSAs or any one of the TAAs, or comprises the same.

14. The multispecific antibody according to claim 12 or 13, wherein the second antigen is CD3 or comprises CD3.

15. The multispecific antibody according to claim 14, wherein the ABR-2 comprises the VH-2 and / or VL-2 and includes a CDR amino acid sequence according to any one of those listed in Table 4B.

16. The aforementioned ABR-2, The aforementioned VH-2, (a) The amino acid sequence of CDRH1-2 includes, or is composed of, one of the heavy chain complementarity determining region 1 (CDRH1) amino acid sequences included in any one of the heavy chain variable domain (VH) amino acid sequences listed in Table 4A, and / or one of the CDRH1 amino acid sequences listed in Table 4B. (b) The amino acid sequence of CDRH2-2 includes, or consists of, one of the heavy chain complementarity determining region 2 (CDRH2) amino acid sequences included in any one of the VH amino acid sequences listed in Table 4A, and / or one of the CDRH2 amino acid sequences listed in Table 4B, and / or (c) The amino acid sequence of CDRH3-2 includes, or consists of, one of the heavy chain complementarity determining region 3 (CDRH3) amino acid sequences included in any one of the VH amino acid sequences listed in Table 4A, and / or one of the CDRH3 amino acid sequences listed in Table 4B, the VH-2 and / or The VL-2 is, (d) The amino acid sequence of CDRL1-2 includes, or is composed of, one of the light chain complementarity determining region 1 (CDRL1) amino acid sequences included in any one of the light chain variable domain (VL) amino acid sequences listed in Table 4A, and / or one of the CDRL1 amino acid sequences listed in Table 4B. (c) The amino acid sequence of CDRL2-2 includes, or consists of, a light chain complementarity determining region 2 (CDRL2) contained in any one of the VL amino acid sequences listed in Table 4A, and / or any one of the CDRL2 amino acid sequences listed in Table 4B, and / or (f) The multispecific antibody according to claim 14 or 15, wherein the VL-2 comprises a light chain complementarity determining region 3 (CDRL3) included in any one of the VL amino acid sequences listed in Table 4A, and / or any one of the CDRL3 amino acid sequences listed in Table 4B, or consists of the same.

17. The aforementioned ABR-2, (a) A set of heavy chain CDR amino acid sequences of a first anti-CD3 antibody selected from the antibodies listed in Tables 4A to 4E, wherein the set of heavy chain CDR amino acid sequences wherein the first anti-CD3 antibody is ADI-26906 or ADI-26921, (b) A set of light chain CDR amino acid sequences of a first anti-CD3 antibody selected from the antibodies listed in Tables 4A to 4E, wherein the set of light chain CDR amino acid sequences wherein the first anti-CD3 antibody is ADI-26906 or ADI-26921, (c) A set of heavy chain and light chain CDR amino acid sequences of a first anti-CD3 antibody selected from the antibodies listed in Tables 4A to 4E, wherein the first anti-CD3 antibody is ADI-26906 or ADI-26921, and further optionally, ABR-1 includes a set of heavy chain and light chain CDR amino acid sequences of any one of antibody numbers 59 to 69 (and further optionally, antibody number 61 or 68), and ABR-2 includes a set of heavy chain and light chain CDR amino acid sequences of ADI-26921, and / or (d) A multispecific antibody according to any one of claims 14 to 16, comprising a set of heavy chain CDR amino acid sequences of a first anti-CD3 antibody selected from the antibodies listed in Tables 4A to 4E, and a set of light chain CDR amino acid sequences of a second anti-CD3 antibody selected from the antibodies listed in Tables 4A to 4E.

18. The ABR-2 includes the VH-2 and the VL-2, (1) The amino acid sequences of CDRH1-2, CDRH2-2, and CDRH3-2 in the VH-2 of ABR-2 include, or consist of, the amino acid sequences of CDRH1, CDRH2, and CDRH3 contained in the VH of the first anti-CD3 antibody, respectively. (2) The amino acid sequences of CDRL1-2, CDRL2-2, and CDRL3-2 in the VL-2 of ABR-2 include, or consist of, the amino acid sequences of CDRL1, CDRL2, and CDRL3 contained in the VL of the first anti-CD3 antibody, respectively. The multispecific antibody according to any one of claims 14 to 17, wherein the first anti-CD3 antibody is one selected from the antibodies listed in Tables 4A to 4E, and optionally the first anti-CD3 antibody is ADI-26906 or ADI-26921.

19. The multispecific antibody according to any one of claims 14 to 17, wherein the ABR-2 comprises the VH-2 and the VL-2, and the amino acid sequences of the CDRH1-2, CDRH2-2, CDRH3-2, CDRL1-2, CDRL2-2, and CDRL3-2 include or consist of the amino acid sequences of the first anti-CD3 antibody CDRH1, CDRH2, CDRH3, CDRL1, CDRL2, and CDRL3, and the first anti-CD3 antibody is one selected from the antibodies listed in Tables 4A to 4E, and optionally the first anti-CD3 antibody is ADI-26906 or ADI-26921.

20. The amino acid sequence of VH-2 includes, or consists of, an amino acid sequence selected from any one of the VH amino acid sequences listed in Table 4A, or a variant thereof having at least about 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity, and / or The multispecific antibody according to any one of claims 14 to 18, wherein the amino acid sequence of VL-2 includes, or comprises, an amino acid sequence selected from any one of the VL amino acid sequences listed in Table 4A, or a variant thereof having at least about 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity.

21. The multispecific antibody according to claim 18 or 19, wherein the amino acid sequences of VH-2 and VL-2 have at least about 80%, at least about 85%, at least about 90%, at least about 91%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, or at least about 99% sequence identity with respect to the respective amino acid sequences of VH and VL of the first anti-CD3 antibody.

22. The multispecific antibody according to claim 14, wherein ABR-2 optionally includes a variable domain pair according to any of those listed in Table 4A, including the VH and VL of ADI-26906 or ADI-26921, and optionally ABR-1 includes a set of heavy and light chain CDR amino acid sequences or a variable domain pair from any one of antibody numbers 59 to 69 (and optionally antibody number 61 or 68), and ABR-2 includes the variable domain pair of ADI-26921.

23. The multispecific antibody according to any one of claims 18, 19, or 21, wherein the amino acid sequences of VH-2 and VL-2 include, or consist of, the respective amino acid sequences of VH and VL of the first anti-CD3 antibody.

24. (1) The ABR-1 is, (a) A heavy chain containing VH-1 and a light chain containing VL-1, wherein ABR-1 is optionally (a-1) Consists of the heavy chain and light chain, (a-2) an Ig molecule containing two heavy chains and two light chains, or a polymer of the Ig molecule, and / or (a-3) A heavy chain containing VH-1 and a light chain containing VL-1, which optionally contain or consist of IgG, IgA, IgE, IgD, or IgM, and optionally IgG1, IgG2, IgG3, or IgG4. (b) Fab including VH-1 and VL-1, Fab' including VH-1 and VL-1, F(ab') including VH-1 and VL-1 ２ F(ab') including the VH-1 and the VL-1 ３ , and / or Fv including the VH-1 and the VL-1, (c) scFv including VH-1 and VL-1, tandem scFv including VH-1 and VL-1, diamond body including VH-1 and VL-1, tria body including VH-1 and VL-1, tetra body including VH-1 and VL-1, scFv-Fc including VH-1 and VL-1, scFv-CH including VH-1 and VL-1, mini body including VH-1 and VL-1, scFv-zipper including VH-1 and VL-1, diamond body-Fc including VH-1 and VL-1, diamond body-CH including VH-1 and VL-1, and / or scFab including VH-1 and VL-1, (d) HCAb containing VH-1, nanobody-Fc containing VH-1, nanobody-CH containing VH-1, camel Ig containing VH-1, IgNAR containing VH-1, and / or any single-stranded variant of the above, and / or (e) comprising sdAb containing VH-1, nanobody containing VH-1, and / or tandem nanobody containing VH-1, and / or (2) The ABR-2 said, (a) A heavy chain containing VH-2 and a light chain containing VL-2, wherein ABR-2 is optionally (a-1) Consists of the heavy chain and light chain, (a-2) an Ig molecule containing two heavy chains and two light chains, or a polymer of the Ig molecule, and / or (a-3) A heavy chain containing VH-2 and a light chain containing VL-2, which optionally contain or consist of IgG, IgA, IgE, IgD, or IgM, and optionally IgG1, IgG2, IgG3, or IgG4. (b) Fab including VH-2 and VL-2, Fab' including VH-2 and VL-2, F(ab') including VH-2 and VL-2 ２ F(ab') including the VH-2 and the VL-2 ３ , and / or Fv including the VH-2 and the VL-2, (c) scFv including VH-2 and VL-2, tandem scFv including VH-2 and VL-2, diamond body including VH-2 and VL-2, tria body including VH-2 and VL-2, tetra body including VH-2 and VL-2, scFv-Fc including VH-2 and VL-2, scFv-CH including VH-2 and VL-2, mini body including VH-2 and VL-2, scFv-zipper including VH-2 and VL-2, diamond body-Fc including VH-2 and VL-2, diamond body-CH including VH-2 and VL-2, and / or scFab including VH-2 and VL-2, (d) HCAb containing VH-2, nanobody-Fc containing VH-2, nanobody-CH containing VH-2, camel Ig containing VH-2, IgNAR containing VH-2, and / or any single-stranded variant of the above, and / or (e) comprising sdAb containing VH-2, a nanobody containing VH-2, and / or a tandem nanobody containing VH-2, Optionally, ABR-1 and ABR-2 are associated or linked to each other via a linker, optionally a peptide linker, and optionally a flexible peptide linker, or via one or more disulfide bonds. The multispecific antibody according to any one of claims 12 to 23, wherein the multispecific antibody optionally includes one of Figures 1 to 6, optionally one of Figures 2 to 6, optionally one of Figures 2A to 2M, 4A to 4C, 5A to 5N, and 6, and optionally one of Figures 2G.

25. (1) The ABR-1 comprises at least one Ig steady domain, optionally one or more of heavy chain steady domain 1 (CH1), heavy chain steady domain 2 (CH2), heavy chain steady domain 3 (CH3), and / or light chain steady domain (CL), and / or a fragment crystallizable (Fc) region, optionally (a) CH1, CH2, and / or CH3 are each of the IgG, IgA, IgE, IgD, or IgM classes, and optionally of the IgG1, IgG2, IgG3, and / or IgG4 subclasses, (b) The CL is a kappa isotype (CLκ) or a lambda isotype (CLλ), and / or (c) The Fc region is of the IgG, IgA, IgE, IgD, or IgM class, and optionally of the IgG1, IgG2, IgG3, and / or IgG4 subclass, (2) The ABR-2 comprises at least one Ig constant domain, optionally one or more of CH1, CH2, CH3, and / or CL, and / or an Fc region, optionally (a) CH1, CH2, and / or CH3 are each of the IgG, IgA, IgE, IgD, or IgM classes, and optionally of the IgG1, IgG2, IgG3, and / or IgG4 subclasses, (b) The CL is CLκ or CLλ, and / or (c) The Fc region is of the IgG, IgA, IgE, IgD, or IgM class, and optionally of the IgG1, IgG2, IgG3, and / or IgG4 subclass, (3) The multispecific antibody contains a common light chain and / or VL-1 and VL-2 have the same or essentially the same amino acid sequence, and optionally the second antigen is human CD3, and the amino acid sequences of VL-1 and VL-2 each have at least about 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity with the amino acid sequence of VL of ADI-26921 (SEQ ID NO: 13270), or include SEQ ID NO: 13270 or consist of them and / or (4) The multispecific antibodies are as follows: (4-i) Heavy chain steady region (CH), optionally CH1, which is manipulated to promote pairing with CLκ rather than CLλ, optionally the manipulation of CH1 is one of those described in WO2021 / 067404, heavy chain steady region (CH), optionally CH1, (4-ii) CH, optionally CH1, which is manipulated to promote pairing with CLλ rather than CLκ, optionally the manipulation of CH1 is one of those described in WO2021 / 067404, CH, optionally CH1, and / or (4-iii) CH, optionally CH1, which is manipulated to promote pairing with the manipulated CL contained in the multispecific antibody more than another CL, optionally the combination of the manipulation of the CH and the manipulation of the CL is one of those described in WO2022 / 150787, CH, optionally CH1, and / or (4-iv) A multispecific antibody according to any one of claims 12 to 24, comprising at least two CHs having different amino acid sequences, and at least two CH3s having different amino acid sequences, wherein the CH3s are manipulated to promote heteromer pairing between the two CHs rather than homomer pairing, and optionally the manipulation of the CH3s is one of those described in WO2022 / 150785.

26. It includes a third antigen-binding region (ABR-3) that binds to a third antigen, and optionally, the ABR-3 is A third heavy chain variable domain (VH-3) comprising a third heavy chain complementarity determining region (CDR) 1 (CDRH1-3), a third heavy chain CDR2 (CDRH2-3), and a third heavy chain CDR3 (CDRH3-3), and / or It includes a third light chain variable domain (VL-3) comprising a third light chain CDR1 (CDRL1-3), a third light chain CDR2 (CDRL2-3), and a third light chain CDR3 (CDRL3-3), The multispecific antibody according to any one of claims 12 to 25, wherein the third antigen is optionally the same as or different from human CD28 and / or the second antigen.

27. The third antigen described above is (a) Human CD3, (b) Cancer antigen, optionally TSA or TAA, (c) Human CD28, (d) Any one of the antigens selected from those listed in Table 3, and / or (e) The multispecific antibody according to claim 26, which is any one of the cancer antigens selected from those listed in Table 3, optionally any one of the TSAs or any one of the TAAs, or comprises them.

28. The multispecific antibody according to claim 26 or 27, wherein the third antigen is CD3 or comprises CD3.

29. The multispecific antibody according to claim 28, wherein the ABR-3 comprises the VH-3 and / or VL-3 and includes a CDR amino acid sequence according to any one of those listed in Table 4B.

30. The aforementioned ABR-3, The aforementioned VH-3, (a) The amino acid sequences of CDRH1-3 include, or consist of, one of the heavy chain complementarity determining region 1 (CDRH1) amino acid sequences included in any one of the heavy chain variable domain (VH) amino acid sequences listed in Table 4A, and / or one of the CDRH1 amino acid sequences listed in Table 4B. (b) The amino acid sequence of CDRH2-3 includes, or consists of, one of the heavy chain complementarity determining region 2 (CDRH2) amino acid sequences included in any one of the VH amino acid sequences listed in Table 4A, and / or one of the CDRH2 amino acid sequences listed in Table 4B, and / or (c) The VH-3 and / or VH-3 whose amino acid sequence includes, or consists of, one of the heavy chain complementarity determining region 3 (CDRH3) amino acid sequences included in any one of the VH amino acid sequences listed in Table 4A, and / or one of the CDRH3 amino acid sequences listed in Table 4B. The VL-3 is, (d) The amino acid sequences of CDRL1-3 include, or consist of, one of the light chain complementarity determining region 1 (CDRL1) amino acid sequences included in any one of the light chain variable domain (VL) amino acid sequences listed in Table 4A, and / or one of the CDRL1 amino acid sequences listed in Table 4B. (c) The amino acid sequence of CDRL2-3 contains, or consists of, a light chain complementarity determining region 2 (CDRL2) included in any one of the VL amino acid sequences listed in Table 4A, and / or any one of the CDRL2 amino acid sequences listed in Table 4B, and / or (f) The multispecific antibody according to claim 28 or 29, wherein the VL-3 comprises a light chain complementarity determining region 3 (CDRL3) included in any one of the VL amino acid sequences listed in Table 4A, and / or any one of the CDRL3 amino acid sequences listed in Table 4B, or consists of the same.

31. The aforementioned ABR-3, (a) A set of heavy chain CDR amino acid sequences of a third anti-CD3 antibody selected from the antibodies listed in Tables 4A to 4E, wherein the set of heavy chain CDR amino acid sequences wherein the third anti-CD3 antibody is ADI-26906 or ADI-26921, (b) A set of light chain CDR amino acid sequences of a third anti-CD3 antibody selected from the antibodies listed in Tables 4A to 4E, wherein the set of light chain CDR amino acid sequences wherein the third anti-CD3 antibody is ADI-26906 or ADI-26921, (c) A set of heavy chain and light chain CDR amino acid sequences of a third anti-CD3 antibody selected from the antibodies listed in Tables 4A to 4E, wherein the third anti-CD3 antibody is ADI-26906 or ADI-26921, and further optionally, ABR-1 includes a set of heavy chain and light chain CDR amino acid sequences of any one of antibody numbers 59 to 69 (and further optionally, antibody number 61 or 68), and ABR-3 includes a set of heavy chain and light chain CDR amino acid sequences of ADI-26921, and / or (d) A multispecific antibody according to any one of claims 28 to 30, comprising a set of heavy chain CDR amino acid sequences of a third anti-CD3 antibody selected from the antibodies listed in Tables 4A to 4E, and a set of light chain CDR amino acid sequences of a fourth anti-CD3 antibody selected from the antibodies listed in Tables 4A to 4E.

32. The ABR-3 includes the VH-3 and the VL-3, (1) The amino acid sequences of CDRH1-3, CDRH2-3, and CDRH3-3 of VH-3 of ABR-3 include, or consist of, the amino acid sequences of CDRH1, CDRH2, and CDRH3 contained in the VH of the third anti-CD3 antibody, respectively. (2) The amino acid sequences of CDRL1-3, CDRL2-3, and CDRL3-3 of VL-3 of ABR-3 include, or consist of, the amino acid sequences of CDRL1, CDRL2, and CDRL3 contained in VL of the third anti-CD3 antibody, respectively. The multispecific antibody according to any one of claims 28 to 31, wherein the third anti-CD3 antibody is one selected from the antibodies listed in Tables 4A to 4E, and optionally the third anti-CD3 antibody is ADI-26906 or ADI-26921.

33. The multispecific antibody according to any one of claims 28 to 32, wherein the amino acid sequences of CDRH1-3, CDRH2-3, CDRH3-3, CDRL1-3, CDRL2-3, and CDRL3-3 of ABR-3's VH-3 and VL-3's CDRH3-3 include or consist of the amino acid sequences of CDRH1, CDRH2, CDRH3, CDRL1, CDRL2, and CDRL3 of the third anti-CD3 antibody, the third anti-CD3 antibody is one selected from the antibodies listed in Tables 4A to 4E, and optionally the third anti-CD3 antibody is ADI-26906 or ADI-26921.

34. The amino acid sequence of the VH-3 of the ABR-3 includes, or consists of, an amino acid sequence selected from any one of the VH amino acid sequences listed in Table 4A, or a variant thereof having at least about 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity, and / or The multispecific antibody according to any one of claims 29 to 33, wherein the amino acid sequence of the VL-3 of the ABR-3 includes, or comprises, an amino acid sequence selected from any one of the VL amino acid sequences listed in Table 4A, or a variant thereof having at least about 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity.

35. The multispecific antibody according to claim 32 or 33, wherein the amino acid sequences of VH-3 and VL-3 of ABR-3 have at least about 80%, at least about 85%, at least about 90%, at least about 91%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, or at least about 99% sequence identity with respect to the respective amino acid sequences of VH and VL of the third anti-CD3 antibody.

36. The multispecific antibody according to any one of claims 28 to 35, wherein ABR3 optionally comprises a variable domain pair according to any of those listed in Table 4A, including the VH and VL of ADI-26906 or ADI-26921, and optionally ABR-1 comprises a set of heavy and light chain CDR amino acid sequences of any one of antibody numbers 59 to 69 (and optionally antibody number 61 or 68), and ABR-3 comprises the variable domain pair of ADI-26921.

37. The multispecific antibody according to any one of claims 32, 33, or 35, wherein the amino acid sequences of VH-3 and VL-3 include, or consist of, the respective amino acid sequences of VH and VL of the third anti-CD3 antibody.

38. The aforementioned ABR-3, (a) A heavy chain containing VH-3 and a light chain containing VL-3, wherein ABR-3 is optionally (a-1) Consists of the heavy chain and light chain, (a-2) an Ig molecule containing two heavy chains and two light chains, or a polymer of the Ig molecule, and / or (a-3) A heavy chain containing VH-3 and a light chain containing VL-3, which optionally contain or consist of IgG, IgA, IgE, IgD, or IgM, and optionally IgG1, IgG2, IgG3, or IgG4. (b) Fab including VH-3 and VL-3, Fab' including VH-3 and VL-3, F(ab') including VH-3 and VL-3 ２ F(ab') including the VH-3 and the VL-3 ３ , and / or Fv including the VH-3 and the VL-3, (c) scFv including VH-3 and VL-3, tandem scFv including VH-3 and VL-3, diamond body including VH-3 and VL-3, tria body including VH-3 and VL-3, tetra body including VH-3 and VL-3, scFv-Fc including VH-3 and VL-3, scFv-CH including VH-3 and VL-3, mini body including VH-3 and VL-3, scFv-zipper including VH-3 and VL-3, diamond body-Fc including VH-3 and VL-3, diamond body-CH including VH-3 and VL-3, and / or scFab including VH-3 and VL-3, (d) HCAb containing VH-3, nanobody-Fc containing VH-3, nanobody-CH containing VH-3, camel Ig containing VH-3, IgNAR containing VH-3, and / or any single-stranded variant of the above, and / or (e) comprising sdAb containing VH-3, nanobody containing VH-3, and / or tandem nanobody containing VH-3, Optionally, (f) The ABR-1 and ABR-2 are associated or linked to each other via a linker, optionally a peptide linker, even more optionally a flexible peptide linker, or via one or more disulfide bonds. (g) The ABR-1 and ABR-3 are associated or linked to each other via a linker, optionally a peptide linker, even more optionally a flexible peptide linker, or via one or more disulfide bonds, and / or (h) The ABR-2 and ABR-3 are associated or linked to each other via a linker, optionally a peptide linker, even more optionally a flexible peptide linker, or via one or more disulfide bonds. The multispecific antibody according to any one of claims 26 to 37, wherein the multispecific antibody optionally includes one of Figures 1 to 6, optionally one of Figures 2 to 6, optionally one of Figures 3A to 3B, 4A to 4C, 5A to 5N, and 6, and optionally the structure shown in the box structure of Figure 2G.

39. (1) The ABR-3 comprises at least one Ig constant domain, optionally one or more of CH1, CH2, CH3, and / or CL, and / or an Fc region, optionally (a) CH1, CH2, and / or CH3 are each of the IgG, IgA, IgE, IgD, or IgM classes, and optionally of the IgG1, IgG2, IgG3, and / or IgG4 subclasses, (b) The CL is CLκ or CLλ, and / or (c) The Fc region is of the IgG, IgA, IgE, IgD, or IgM class, and optionally of the IgG1, IgG2, IgG3, and / or IgG4 subclass, (2) The multispecific antibody contains a common light chain and / or VL-1 and VL-2 have the same or essentially the same amino acid sequence and / or VL-1 and VL-3 have the same or essentially the same amino acid sequence and / or VL-2 and VL-3 have the same or essentially the same amino acid sequence, and optionally (i) the second antigen is human CD3, and the amino acid sequences of VL-1 and VL-2 are, individually, at least about 80%, 85%, 90%, 91%, and 92% of the amino acid sequence of VL of ADI-26921 (SEQ ID NO: 13270). (ii) The third antigen is human CD3, and the amino acid sequences of VL-1 and VL-3 each have at least about 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity with the amino acid sequence of VL of ADI-26921 (SEQ ID NO: 13270), or include or consist of SEQ ID NO: 13270, and / or (3) The multispecific antibody is as follows: (3-i) Heavy chain steady region (CH), optionally CH1, which is manipulated to promote pairing with CLκ rather than CLλ, optionally the manipulation of CH1 is one of those described in WO2021 / 067404, heavy chain steady region (CH), optionally CH1, (3-ii) CH, optionally CH1, which is operated to promote pairing with CLλ rather than CLκ, optionally the operation of CH1 is one of those described in WO2021 / 067404, CH, optionally CH1, and / or (3-iii) CH, optionally CH1, which is manipulated to promote pairing with the manipulated CL contained in the multispecific antibody more than another CL, optionally the combination of the manipulation of the CH and the manipulation of the CL is one of those described in WO2022 / 150787, CH, optionally CH1, and / or (3-iv) A multispecific antibody according to any one of claims 26 to 38, comprising at least two CHs having different amino acid sequences, and optionally two CH3s having different amino acid sequences, wherein the CH3s are manipulated to promote heteromer pairing between the two CHs rather than homomer pairing, and optionally the manipulation of the CH3s is one of those described in WO2022 / 150785.

40. It includes a fourth antigen-binding region (ABR-4) that binds to a fourth antigen, and optionally, the ABR-4 is A fourth heavy chain variable domain (VH-4) comprising a fourth heavy chain complementarity determining region (CDR) 1 (CDRH1-4), a fourth heavy chain CDR2 (CDRH2-4), and a fourth heavy chain CDR3 (CDRH3-4), and / or It includes a fourth light chain variable domain (VL-4) comprising a fourth light chain CDR1 (CDRL1-4), a fourth light chain CDR2 (CDRL2-4), and a fourth light chain CDR3 (CDRL3-4), The multispecific antibody according to any one of claims 12 to 39, wherein the fourth antigen is optionally the same as or different from human CD28, the second antigen, and / or the third antigen.

41. The fourth antigen is (a) Human differentiation cluster 3 (CD3), (b) Cancer antigen, optionally TSA or TAA, (c) Human CD28, (d) Any one of the antigens selected from those listed in Table 3, and / or (e) The multispecific antibody according to claim 40, comprising any one of the cancer antigens selected from those listed in Table 3, and optionally any one of the TSAs or any one of the TAAs.

42. The multispecific antibody according to claim 40, wherein the fourth antigen is CD3 or comprises CD3.

43. The multispecific antibody according to claim 42, wherein the ABR-4 comprises the VH-4 and / or VL-4 and includes a CDR amino acid sequence according to any one of those listed in Table 4B.

44. The aforementioned ABR-4, The aforementioned VH-4, (a) The amino acid sequences of CDRH1-4 include, or consist of, one of the heavy chain complementarity determining region 1 (CDRH1) amino acid sequences included in any one of the heavy chain variable domain (VH) amino acid sequences listed in Table 4A, and / or one of the CDRH1 amino acid sequences listed in Table 4B. (b) The amino acid sequence of CDRH2-4 includes, or consists of, one of the heavy chain complementarity determining region 2 (CDRH2) amino acid sequences included in any one of the VH amino acid sequences listed in Table 4A, and / or one of the CDRH2 amino acid sequences listed in Table 4B, and / or (c) The VH-4 and / or the VH-4 whose amino acid sequence includes, or consists of, one of the heavy chain complementarity determining region 3 (CDRH3) amino acid sequences included in any one of the VH amino acid sequences listed in Table 4A, and / or one of the CDRH3 amino acid sequences listed in Table 4B. The VL-4 is, (d) The amino acid sequences of CDRL1-4 include, or consist of, one of the light chain complementarity determining region 1 (CDRL1) amino acid sequences included in any one of the light chain variable domain (VL) amino acid sequences listed in Table 4A, and / or one of the CDRL1 amino acid sequences listed in Table 4B. (c) The amino acid sequence of CDRL2-4 contains, or consists of, a light chain complementarity determining region 2 (CDRL2) included in any one of the VL amino acid sequences listed in Table 4A, and / or any one of the CDRL2 amino acid sequences listed in Table 4B, and / or (f) The multispecific antibody according to claim 42 or 43, wherein the VL-4 comprises a light chain complementarity determining region 3 (CDRL3) included in any one of the VL amino acid sequences listed in Table 4A, and / or any one of the CDRL3 amino acid sequences listed in Table 4B, or consists of the same.

45. The aforementioned ABR-4, (a) A set of heavy chain CDR amino acid sequences of a fifth anti-CD3 antibody selected from the antibodies listed in Tables 4A to 4E, wherein the set of heavy chain CDR amino acid sequences wherein the fifth anti-CD3 antibody is ADI-26906 or ADI-26921, (b) A set of light chain CDR amino acid sequences of a fifth anti-CD3 antibody selected from the antibodies listed in Tables 4A to 4E, wherein the set of light chain CDR amino acid sequences wherein the fifth anti-CD3 antibody is ADI-26906 or ADI-26921, (c) A set of heavy chain and light chain CDR amino acid sequences of a fifth anti-CD3 antibody selected from the antibodies listed in Tables 4A to 4E, wherein the fifth anti-CD3 antibody is ADI-26906 or ADI-26921, and further optionally, ABR-1 includes a set of heavy chain and light chain CDR amino acid sequences of any one of antibody numbers 59 to 69 (and further optionally, antibody number 61 or 68), and ABR-4 includes a set of heavy chain and light chain CDR amino acid sequences of ADI-26921, and / or (d) A multispecific antibody according to any one of claims 42 to 44, comprising a set of heavy chain CDR amino acid sequences of a fifth anti-CD3 antibody selected from the antibodies listed in Tables 4A to 4E, and a set of light chain CDR amino acid sequences of a sixth anti-CD3 antibody selected from the antibodies listed in Tables 4A to 4E.

46. The ABR-4 includes the VH-4 and the VL-4, (1) The amino acid sequences of CDRH1-4, CDRH2-4, and CDRH3-4 of the VH-4 of the ABR-4 include, or consist of, the amino acid sequences of CDRH1, CDRH2, and CDRH3 contained in the VH of the fifth anti-CD3 antibody, respectively. (2) The amino acid sequences of CDRL1-4, CDRL2-4, and CDRL3-4 of VL-4 of ABR-4 include, or consist of, the amino acid sequences of CDRL1, CDRL2, and CDRL3 contained in VL of the fifth anti-CD3 antibody, respectively. The multispecific antibody according to any one of claims 42 to 45, wherein the fifth anti-CD3 antibody is one selected from the antibodies listed in Tables 4A to 4E, and optionally the fifth anti-CD3 antibody is ADI-26906 or ADI-26921.

47. The multispecific antibody according to any one of claims 42 to 46, wherein the amino acid sequences of CDRH1-4, CDRH2-4, CDRH3-4, CDRL1-4, CDRL2-4, and CDRL3-4 of ABR-4 and VL-4 include or consist of the amino acid sequences of CDRH1, CDRH2, CDRH3, CDRL1, CDRL2, and CDRL3 of the fifth anti-CD3 antibody, and the fifth anti-CD3 antibody is one selected from the antibodies listed in Tables 4A to 4E.

48. The amino acid sequence of VH-4 includes, or consists of, an amino acid sequence selected from any one of the VH amino acid sequences listed in Table 4A, or a variant thereof having at least about 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity, and / or The multispecific antibody according to any one of claims 43 to 47, wherein the amino acid sequence of VL-4 includes, or comprises, an amino acid sequence selected from any one of the VL amino acid sequences listed in Table 4A, or a variant thereof having at least about 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity.

49. The multispecific antibody according to claim 46 or 47, wherein the amino acid sequences of VH-4 and VL-4 have at least about 80%, at least about 85%, at least about 90%, at least about 91%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, or at least or at least about 99% sequence identity with respect to the respective amino acid sequences of VH and VL of the fifth anti-CD3 antibody.

50. The multispecific antibody according to claim 49, wherein ABR-4 optionally comprises a variable domain pair according to any of those listed in Table 4A, including the VH and VL of ADI-26906 or ADI-26921, and optionally ABR-1 comprises a set of heavy and light chain CDR amino acid sequences of any one of antibody numbers 59 to 69 (and optionally antibody number 61 or 68), and ABR-4 comprises the variable domain pair of ADI-26921.

51. The multispecific antibody according to any one of claims 46, 47, or 49, wherein the amino acid sequences of VH-4 and VL-4 include, or consist of, the respective amino acid sequences of VH and VL of the fifth anti-CD3 antibody.

52. The aforementioned ABR-4, (a) A heavy chain containing VH-4 and a light chain containing VL-4, wherein ABR-4 is optionally (a-1) Consists of the heavy chain and light chain, (a-2) an Ig molecule containing two heavy chains and two light chains, or a polymer of the Ig molecule, and / or (a-3) A heavy chain containing VH-4 and a light chain containing VL-4, which optionally contain or consist of IgG, IgA, IgE, IgD, or IgM, and optionally IgG1, IgG2, IgG3, or IgG4. (b) Fab including VH-4 and VL-4, Fab' including VH-4 and VL-4, F(ab') including VH-4 and VL-4 ２ F(ab') including the VH-4 and the VL-4 ３ , and / or Fv including the VH-4 and the VL-4, (c) scFv including VH-4 and VL-4, tandem scFv including VH-4 and VL-4, diamond body including VH-4 and VL-4, tria body including VH-4 and VL-4, tetra body including VH-4 and VL-4, scFv-Fc including VH-4 and VL-4, scFv-CH including VH-4 and VL-4, mini body including VH-4 and VL-4, scFv-zipper including VH-4 and VL-4, diamond body-Fc including VH-4 and VL-4, diamond body-CH including VH-4 and VL-4, and / or scFab including VH-4 and VL-4 (d) HCAb containing VH-4, nanobody-Fc containing VH-4, nanobody-CH containing VH-4, camel Ig containing VH-4, IgNAR containing VH-4, and / or any single-stranded variant of the above, and / or (e) comprising sdAb containing VH-4, a nanobody containing VH-4, and / or a tandem nanobody containing VH-4, Optionally, (f) The ABR-1 and ABR-2 are associated or linked to each other via a linker, optionally a peptide linker, even more optionally a flexible peptide linker, or via one or more disulfide bonds. (g) The ABR-1 and ABR-3 are associated or linked to each other via a linker, optionally a peptide linker, optionally a flexible peptide linker, or via one or more disulfide bonds. (h) The ABR-1 and ABR-4 are associated or linked to each other via a linker, optionally a peptide linker, even more optionally a flexible peptide linker, or via one or more disulfide bonds. (i) The ABR-2 and ABR-3 are associated or linked to each other via a linker, optionally a peptide linker, even more optionally a flexible peptide linker, or via one or more disulfide bonds, (j) The ABR-2 and ABR-4 are associated or linked to each other via a linker, optionally a peptide linker, even more optionally a flexible peptide linker, or via one or more disulfide bonds, and / or (k) The ABR-3 and the ABR-4 are associated or linked to each other via a linker, optionally a peptide linker, even more optionally a flexible peptide linker, or via one or more disulfide bonds. The multispecific antibody according to any one of claims 40 to 51, further and optionally comprising any one of Figures 1 to 6, optionally any one of Figures 4 to 6, further optionally any one of Figures 4A to 4C, 5A to 5N, and 6, and further optionally any structure shown in the structure within the box of Figure 2G.

53. (1) The ABR-4 comprises at least one Ig constant domain, optionally one or more of CH1, CH2, CH3, and / or CL, and / or an Fc region, and optionally, (a) CH1, CH2, and / or CH3 are each of the IgG, IgA, IgE, IgD, or IgM classes, and optionally of the IgG1, IgG2, IgG3, and / or IgG4 subclasses, (b) The CL is CLκ or CLλ, and / or (c) The Fc region is of the IgG, IgA, IgE, IgD, or IgM class, and optionally of the IgG1, IgG2, IgG3, and / or IgG4 subclass, (2) The multispecific antibody contains a common light chain and / or VL-1 and VL-2 have the same or essentially the same amino acid sequence and / or VL-1 and VL-3 have the same or essentially the same amino acid sequence and / or VL-1 and VL-4 have the same or essentially the same amino acid sequence and / or VL-2 and VL-3 have the same or essentially the same amino acid sequence and / or VL-2 and the preceding VL-4 has the same or essentially the same amino acid sequence, and / or VL-3 and VL-4 have the same or essentially the same amino acid sequence, and optionally (i) the second antigen is human CD3, and the amino acid sequences of VL-1 and VL-2 are, individually, at least about 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, and 98% of the amino acid sequence of VL of ADI-26921 (SEQ ID NO: 13270). (ii) The third antigen is human CD3, and the amino acid sequences of VL-1 and VL-3 each have at least about 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity with the amino acid sequence of VL of ADI-26921 (SEQ ID NO: 13270), or SEQ ID NO: 1327 (iii) The fourth antigen is human CD3, and the amino acid sequences of VL-1 and VL-4 each have at least about 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% sequence identity with the amino acid sequence of VL of ADI-26921 (SEQ ID NO: 13270), or include SEQ ID NO: 13270, and / or (3) The multispecific antibody is as follows: (3-i) Heavy chain steady region (CH), optionally CH1, which is manipulated to promote pairing with CLκ rather than CLλ, optionally the manipulation of CH1 is one of those described in WO2021 / 067404, heavy chain steady region (CH), optionally CH1, (3-ii) CH, optionally CH1, which is operated to promote pairing with CLλ rather than CLκ, optionally the operation of CH1 is one of those described in WO2021 / 067404, CH, optionally CH1, and / or (3-iii) CH, optionally CH1, which is manipulated to promote pairing with the manipulated CL contained in the multispecific antibody more than another CL, optionally the combination of the manipulation of the CH and the manipulation of the CL is one of those described in WO2022 / 150787, CH, optionally CH1, and / or (3-iv) A multispecific antibody according to any one of claims 40 to 52, comprising at least two CHs having different amino acid sequences, and optionally two CH3s having different amino acid sequences, wherein the CH3s are manipulated to promote heteromer pairing between the two CHs rather than homomer pairing, and optionally the manipulation of the CH3s is one of those described in WO2022 / 150785.

54. (A) At least one antigen-binding region (ABR-A) that binds to antigen A, (A-i) At least one heavy chain A comprising a heavy chain variable domain A (VH-A) and a heavy chain constant region A (CH-A) from the N-terminus to the C-terminus, wherein the CH-A is optionally (a) Heavy chain steady domain 1A (CH1-A), hinge (hinge-A), heavy chain steady domain 2A (CH2-A), and / or heavy chain steady domain 3A (CH3-A), and / or (b) at least one heavy chain A comprising CH1-A, hinge-A, CH2-A, and CH3-A from the N-terminus to the C-terminus, and optionally (A-ii) comprising at least one light chain A including a light chain variable domain A (VL-A) and a light chain constant domain A (CL-A), The heavy chain A and the light chain A (if present) optionally pair with each other via at least one disulfide bond, and have at least one antigen-binding region (ABR-A) that binds to antigen A, (B) At least one antigen-binding region B (ABR-B) comprising a Fab (Fab-B) that binds to antigen B, (B-i) Heavy chain variable domain B (VH-B), and heavy chain steady region B (CH-B) which includes at least heavy chain steady domain 1B (CH1-B), and (B-ii) Light chain B, which includes a variable light chain domain B (VL-B) and a constant light chain domain B (CL-B), The heavy chain B and the light chain B optionally pair with each other via at least one disulfide bond to form an antigen-binding region that binds to the antigen B, and includes at least one antigen-binding region B (ABR-B), which includes a Fab (Fab-B) that binds to the antigen B, Optionally, (a) The heavy chain B, optionally the C-terminus or N-terminus of the heavy chain B, (a-1) The heavy chain A, optionally at the N-terminus or C-terminus of the heavy chain A, (a-2) If the light chain A (if present) is present, optionally at the N-terminus or C-terminus of the light chain A (if present) They are optionally associated or linked via linkers, optionally further optionally via peptide linkers, optionally further optionally via flexible peptide linkers, and / or (b) The light chain B, optionally the C-terminus or N-terminus of the light chain B, (b-1) If the light chain A (if present) is present, optionally the N-terminus or C-terminus of the light chain A (if present) (b-2) The heavy chain A, optionally at the N-terminus or C-terminus of the heavy chain A, They are optionally associated or linked via linkers, optionally via peptide linkers, and optionally via flexible peptide linkers. Furthermore, optionally, the multispecific antibody may include a structure according to any one of Figures 1 to 6, optionally one of Figures 2A to 2I, 3A to 3B, 4A to 4C, and 5A to 5I, and optionally the structure within the box in Figure 2G. Furthermore, optionally, the multispecific antibody according to any one of claims 12 to 53, wherein antigen B is the same as or different from antigen A.

55. (A) At least one antigen-binding region (ABR-A) that binds to antigen A, (A-i) At least one heavy chain A, which optionally includes a heavy chain variable domain A (VH-A) and a heavy chain constant region A (CH-A) from the N-terminus to the C-terminus, wherein optionally the CH-A is (a) Heavy chain steady domain 1A (CH1-A), hinge (hinge-A), heavy chain steady domain 2A (CH2-A), and / or heavy chain steady domain 3A (CH3-A), and / or (b) at least one heavy chain A comprising CH1-A, hinge-A, CH2-A, and CH3-A from the N-terminus to the C-terminus, and optionally (A-ii) comprising at least one light chain A including a light chain variable domain A (VL-A) and a light chain constant domain A (CL-A), The heavy chain A and the light chain A (if present) optionally pair with each other via at least one disulfide bond to form an antigen-binding region that binds to antigen A, comprising at least one antigen-binding region (ABR-A) that binds to antigen A, (B) At least one antigen-binding region B (ABR-B) comprising an scFv (scFv-B) that binds to antigen B, (B-i) Heavy chain variable domain B (VH-B), and (B-ii) light chain variable domain B (VL-B), comprising at least one antigen-binding region B (ABR-B) including an scFv (scFv-B) that binds to antigen B, (a) The C-terminus of the VH-B is connected to the N-terminus of the VL-B, and optionally the scFv-B includes the VH-B, linker, and VL-B from the N-terminus to the C-terminus, or (b) The C-terminus of the VL-B is connected to the N-terminus of the VH-B, and optionally the scFv-B includes the VL-B, linker, and VH-B from the N-terminus to the C-terminus. Optionally, the scFv-B, and optionally the C-terminus or N-terminus of the scFv-B, (1) The heavy chain A, optionally at the N-terminus or C-terminus of the heavy chain A, and / or (2) If the light chain A (if present) is present, optionally, at the N-terminus or C-terminus of the light chain A (if present) They are optionally associated or linked via linkers, optionally further optionally via peptide linkers, optionally further optionally via flexible peptide linkers, and / or Furthermore, optionally, the multispecific antibody comprises a structure optionally according to one of Figures 2A, 2F, 2J, 3A-3B, 4A-4C, 5C-5G, and 5J-5N, as shown in any one of Figures 1-6. A multispecific antibody according to any one of claims 12 to 53, wherein, optionally, the antigen B is the same as or different from the antigen A.

56. (A) At least one antigen-binding region (ABR-A) that binds to antigen A, (A-i) At least one heavy chain A, which optionally includes a heavy chain variable domain A (VH-A) and a heavy chain constant region A (CH-A) from the N-terminus to the C-terminus, wherein optionally the CH-A is (a) Heavy chain steady domain 1A (CH1-A), hinge (hinge-A), heavy chain steady domain 2A (CH2-A), and / or heavy chain steady domain 3A (CH3-A), and / or (b) at least one heavy chain A comprising CH1-A, hinge-A, CH2-A, and CH3-A from the N-terminus to the C-terminus, and optionally (A-ii) comprising at least one light chain A including a light chain variable domain A (VL-A) and a light chain constant domain A (CL-A), The heavy chain A and the light chain A (if present) optionally pair with each other via at least one disulfide bond to form an antigen-binding region that binds to antigen A, comprising at least one antigen-binding region (ABR-A) that binds to antigen A, (B) At least one antigen-binding region B (ABR-B) comprising an scFab (scFab-B) that binds to antigen B, (B-i) Heavy chain variable domain B (VH-B), and heavy chain steady region B (CH-B) which includes at least heavy chain steady domain 1B (CH1-B), and (B-ii) comprising a light chain B comprising a light chain variable domain B (VL-B) and a light chain constant domain B (CL-B), comprising at least one antigen-binding region B (ABR-B) comprising an antigen-binding scFab (scFab-B) comprising an antigen-binding scFab (scFab-B), (a) The C-terminus of the heavy chain B is connected to the N-terminus of the light chain B, and optionally the scFab-B includes the heavy chain B, a linker, and the light chain B from the N-terminus to the C-terminus, or (b) The C-terminus of the light chain B is connected to the N-terminus of the heavy chain B, and optionally the scFab-B includes the light chain B, a linker, and the heavy chain B from the N-terminus to the C-terminus. Optionally, the scFab-B, and optionally, the C-terminus or N-terminus of the scFab-B, (1) The heavy chain A, optionally at the N-terminus or C-terminus of the heavy chain A, and / or (2) If the light chain A (if present) is present, optionally, at the N-terminus or C-terminus of the light chain A (if present) They are optionally associated or linked via linkers, optionally further optionally via peptide linkers, optionally further optionally via flexible peptide linkers, and / or Furthermore, optionally, the multispecific antibody comprises a structure optionally according to one of Figures 2A, 2F, 2K, 3A-3B, and 4A-4C, as shown in any one of Figures 1-6. A multispecific antibody according to any one of claims 12 to 53, wherein, optionally, the antigen B is the same as or different from the antigen A.

57. (A) At least one antigen-binding region (ABR-A) that binds to antigen A, (A-i) At least one heavy chain A, which optionally includes a heavy chain variable domain A (VH-A) and a heavy chain constant region A (CH-A) from the N-terminus to the C-terminus, wherein optionally the CH-A is (a) Heavy chain steady domain 1A (CH1-A), hinge (hinge-A), heavy chain steady domain 2A (CH2-A), and / or heavy chain steady domain 3A (CH3-A), and / or (b) at least one heavy chain A comprising CH1-A, hinge-A, CH2-A, and CH3-A from the N-terminus to the C-terminus, and optionally (A-ii) comprising at least one light chain A including a light chain variable domain A (VL-A) and a light chain constant domain A (CL-A), The heavy chain A and the light chain A optionally pair with each other via at least one disulfide bond to form an antigen-binding region that binds to antigen A, comprising at least one antigen-binding region (ABR-A) that binds to antigen A, (B) comprising at least one antigen-binding region B (ABR-B) which includes a heavy chain variable domain B (VH-B) and an sdAb (sdAb-B) that binds to antigen B, Optionally, the C-terminus or N-terminus of sdAb, (1) The heavy chain A, optionally at the N-terminus or C-terminus of the heavy chain A, and / or (2) If the light chain A (if present) is present, optionally, at the N-terminus or C-terminus of the light chain A (if present) They are optionally associated or linked via linkers, optionally further optionally via peptide linkers, optionally further optionally via flexible peptide linkers, and / or Furthermore, optionally, the multispecific antibody is further modified to omit at least one VL, and comprises a structure optionally according to one of Figures 2 to 6, as illustrated in any one of Figures 1 to 6. Furthermore, optionally, the multispecific antibody according to any one of claims 12 to 53, wherein antigen B is the same as or different from antigen A.

58. (A) At least one antigen-binding region (ABR-A) that binds to antigen A, (A-i) At least one heavy chain A, which optionally includes a heavy chain variable domain A (VH-A) and a heavy chain constant region A (CH-A) from the N-terminus to the C-terminus, wherein optionally the CH-A is (a) Heavy chain steady domain 1A (CH1-A), Hinge A (Hinge-A), Heavy chain steady domain 2A (CH2-A), and / or Heavy chain steady domain 3A (CH3-A), and / or (b) at least one heavy chain A comprising CH1-A, hinge-A, CH2-A, and CH3-A from the N-terminus to the C-terminus, and optionally (A-ii) comprising at least one light chain A including a light chain variable domain A (VL-A) and a light chain constant domain A (CL-A), The heavy chain A and the light chain A (if present) optionally pair with each other via at least one disulfide bond to form an antigen-binding region that binds to antigen A, comprising at least one antigen-binding region (ABR-A) that binds to antigen A, (B) At least one antigen-binding region (ABR-B) that binds to antigen B, (B-i) At least one heavy chain B comprising a heavy chain variable domain B (VH-B) and a heavy chain constant region B (CH-B) from the N-terminus to the C-terminus, wherein the CH-B is optionally (a) Heavy chain steady domain 1B (CH1-B), Hinge B (Hinge-B), Heavy chain steady domain 2B (CH2-B), and / or Heavy chain steady domain 3B (CH3-A), and / or (b) at least one heavy chain B comprising CH1-B, hinge-B, CH2-B, and CH3-B from the N-terminus to the C-terminus, and optionally (B-ii) comprising at least one light chain B including a variable light chain domain B (VL-B) and a constant light chain domain B (CL-B), The heavy chain B and the light chain B (if present) optionally pair with each other via at least one disulfide bond to form an antigen-binding region that binds to antigen B, comprising at least one antigen-binding region (ABR-B) that binds to antigen B, Selectively, heavy chain A and heavy chain B pair with each other via at least one disulfide bond. Furthermore, optionally, (a) (a-1) Whether the light chain A (if present) and the light chain B (if present) have the same or essentially the same amino acid sequence, or whether they are a common light chain, (a-2) (a-2i) If CH-A and / or CL-A (if present), CH1-A and / or CL-A (if present) are optionally operated to promote pairing between CH-A and CL-A more than between CH-A and CL-B and / or between CH-B and CL-A, optionally, (1) The CL-A is CLκ, and the CH-A, optionally the CH1-A, is manipulated to promote pairing with CLκ more than CLλ, optionally the manipulation of the CH1-A is one of those described in WO2021 / 067404, (2) The CL-A is CLλ, and the CH-A, optionally the CH1-A, is operated to promote pairing with CLλ more than CLκ, optionally the operation of the CH1-A is one of those described in WO2021 / 067404, or (3) Both CH-A, optionally CH1-A, and CL-A are operated to promote pairing between CH-A and CL-A more than pairing between CH-A and CL-B and / or between CH-B and CL-A, optionally the combination of the operation of CH-A and the operation of CL-A is one of those described in WO2022 / 150787 and / or (a-2ii) If CH-B and / or CL-B (if present), CH1-B and / or CL-B (if present) are optionally operated to promote pairing between CH-B and CL-B more than between CH-B and CL-A and / or between CH-A and CL-B, optionally, (1) The CL-B is CLλ, and the CH-B, optionally the CH1-B, is operated to promote pairing with CLλ more than CLκ, optionally the operation of the CH1-B is one of those described in WO2021 / 067404, (2) The CL-B is CLκ, and the CH-B, optionally the CH1-B, is manipulated to promote pairing with CLκ more than CLλ, optionally the manipulation of the CH1-B is one of those described in WO2021 / 067404, or (3) Both CH-B, optionally CH1-B, and CL-B are operated to promote pairing between CH-B and CL-B more than pairing between CH-B and CL-A and / or pairing between CH-A and CL-B, optionally the combination of the operation of CH-B and the operation of CL-B is one of those described in WO2022 / 150787 and / or (b) CH-A and / or CH-B, optionally CH3-A and / or CH3-B and / or optionally CH3-A and / or CH3-B are manipulated to promote heteromer pairing between CH-A and CH-B more than homomer CH-A pairing and / or homomer CH-B pairing, wherein optionally the manipulation of CH3-A and / or CH3-B is one of those described in WO2022 / 150785, Furthermore, optionally, the multispecific antibody may include a structure according to any one of Figures 1 to 6, optionally one of Figures 2G to 2K, 3A to 3B, 4A to 4C, and 5A to 5N, and further optionally, a structure according to the structure in the box in Figure 2G. A multispecific antibody according to any one of claims 12 to 53, wherein, optionally, the antigen B is the same as or different from the antigen A.

59. (I) (A) The antigen A is human CD28, the VH-A is the VH-1 or contains the same, and / or the VL-A (if present) is the VL-1 or contains the same. (B) The antigen B is the second antigen, the VH-B is the VH-2 or contains the same, and / or the VL-B (if present) is the VL-2 or contains the same, (II) (A) The antigen A is the second antigen, the VH-A is the VH-2 or contains the VH-2, and / or the VL-A (if present) is the VL-2 or contains the VL-2, (B) A multispecific antibody according to any one of claims 54 to 58, in accordance with any one of claims 12 to 25, wherein the antigen B is human CD28, the VH-B is or comprises the VH-1, and / or the VL-B (if present) is or comprises the VL-1.

60. (C) At least one antigen-binding region (ABR-C) that binds to antigen C, (C-1) A Fab (Fab-C) that binds to antigen C, (C-1-i) Heavy chain variable domain C (VH-C), and heavy chain steady region C (CH-C) including at least heavy chain steady domain 1C (CH1-C), and (C-ii) Light chain C, which includes a variable light chain domain C (VL-C) and a constant light chain domain C (CL-C), The heavy chain C and the light chain C are optionally paired with each other via at least one disulfide bond, and Fab (Fab-C) is bound to antigen C. (C-2) scFv (scFv-C) that binds to antigen C, (C-i) Heavy chain variable domain C (VH-C), and (C-ii) Light chain variable domain C (VL-C), (a) The C-terminus of the VH-C is connected to the N-terminus of the VL-C, and optionally the scFv-C includes the VH-C, linker, and VL-C from the N-terminus to the C-terminus, or (b) The C-terminus of the VL-C is linked to the N-terminus of the VH-C, and optionally the scFv-C contains the VL-C, a linker, and the VH-C, and is an scFv (scFv-C) that binds to antigen C, from the N-terminus to the C-terminus. (C-3) a(scFab-C) that binds to antigen C, (C-i) Heavy chain variable domain C (VH-C), and heavy chain steady region C (CH-C) which includes at least heavy chain steady domain 1C (CH1-C), and (C-ii) Light chain C, which includes a variable light chain domain C (VL-C) and a constant light chain domain C (CL-C), (a) The C-terminus of the heavy chain C is connected to the N-terminus of the light chain C, and optionally the scFab-C includes the heavy chain C, a linker, and the light chain B from the N-terminus to the C-terminus, or (b) The C-terminus of the light chain C is linked to the N-terminus of the heavy chain C, and optionally the scFab-C is a(scFab-C) that binds to antigen C, with the light chain C, linker, and heavy chain C connected from the N-terminus to the C-terminus, or (C-4) Further comprising at least one antigen-binding region (ABR-C) that binds to antigen C, and containing at least one sdAb (sdFab-C) that binds to antigen C, which includes heavy chain variable domain C (VH-C), Furthermore, optionally, the multispecific antibody includes a structure optionally according to one of Figures 2 to 6, as shown in one of Figures 1 to 6. A multispecific antibody according to any one of claims 54 to 58, wherein, optionally, the antigen C is the same as or different from antigen A and / or antigen B.

61. In (C-1), Fab-C is associated with or connected to ABR-A and / or ABR-B, and optionally, (a) The heavy chain C, optionally the C-terminus or N-terminus of the heavy chain C, is associated with or linked to the ABR-A and / or the ABR-B, optionally the C-terminus and / or N-terminus of the heavy chain A and / or the light chain A (if present) of the ABR-A, and / or the C-terminus and / or N-terminus of the heavy chain B (if present) and / or the light chain B (if present), the scFv-B (if present), the scFab-B (if present), or the sdAb-B (if present) of the ABR-B, are optionally associated with or linked to the C-terminus and / or N-terminus via linkers, and / or (b) The light chain C, optionally the C-terminus or N-terminus of the light chain C is associated with or linked to the ABR-A and / or the ABR-B, optionally the C-terminus and / or N-terminus of the heavy chain A and / or the light chain A (if present) of the ABR-A, and / or the heavy chain B (if present) and / or the light chain B (if present), the scFv-B (if present), the scFab-B (if present), or the sdAb-B (if present) is associated with or linked to the C-terminus and / or N-terminus via a linker, In (C-2), the scFv-C, optionally the C-terminus or N-terminus of the scFv-C, is associated with or linked to the ABR-A and / or the ABR-B, optionally the C-terminus and / or N-terminus of the heavy chain A and / or the light chain A (if present) of the ABR-A, and / or the heavy chain B (if present) and / or the light chain B (if present), the scFv-B (if present), the scFab-B (if present), or the sdAb-B (if present) is associated with or linked to the C-terminus and / or N-terminus via a linker, In (C-3), the scFab-C, optionally the C-terminus or N-terminus of the scFab-C, is associated with or linked to the ABR-A and / or the ABR-B, optionally the C-terminus and / or N-terminus of the heavy chain A and / or light chain A (if present) of the ABR-A, and / or the heavy chain B (if present) and / or light chain B (if present) of the ABR-B, the scFv-B (if present), the scFab-B (if present), or the C-terminus and / or N-terminus of the sdAb-B (if present) are optionally associated with or linked to the C-terminus and / or N-terminus of the sdAb-B (if present), or In (C-4), the sdFab-C, optionally the C-terminus or N-terminus of the sdAb-C, is associated with or linked to the ABR-A and / or the ABR-B, optionally the C-terminus and / or N-terminus of the heavy chain A and / or the light chain A (if present) of the ABR-A, and / or the heavy chain B (if present) and / or the light chain B (if present) of the ABR-B, the scFv-B (if present), the scFab-B (if present), or the C-terminus and / or N-terminus of the sdAb-B (if present) are optionally associated with or linked to the C-terminus and / or N-terminus of the sdAb-B (if present), optionally linked with or linked to the C-terminus and / or N-terminus of the sdFab-C, optionally linked with the sdAb-C, optionally the C-terminus or N-terminus of the sdAb-C, optionally linked with the ABR-A and / or N-terminus of the heavy chain A and / or the light chain A (if present) of the ABR-A, and / or the heavy chain B (if present) and / or the light chain B (if present) of the ABR-B, optionally linked with or linked to the C-terminus and / or N-terminus of the scFv-B (if present), if present. The multispecific antibody according to claim 60, wherein optionally, the optionally selected linker in (C-1), (C-2), (C-3), and / or (C-4) is a peptide linker, or optionally a flexible peptide linker.

62. (I) (A) The antigen A is human CD28, the VH-A is the VH-1 or contains the same, and / or the VL-A (if present) is the VL-1 or contains the same. (B) The antigen B is the second antigen, the VH-B is the VH-2 or contains the same, and / or the VL-B (if present) is the VL-2 or contains the same. (C) The antigen C is the third antigen, the VH-C is the VH-3 or contains the VH-3, and / or the VL-C (if present) is the VL-3 or contains the VL-3. (II) (A) The antigen A is human CD28, the VH-A is the VH-1 or contains the same, and / or the VL-A (if present) is the VL-1 or contains the same (B) The antigen B is the third antigen, the VH-B is the VH-3 or contains the same, and / or the VL-B (if present) is the VL-3 or contains the same. (C) The antigen C is the second antigen, the VH-C is the VH-2 or contains the VH-2, and / or the VL-C (if present) is the VL-2 or contains the VL-2. (III) (A) The antigen A is the second antigen, the VH-A is the VH-2 or contains the same, and / or the VL-A (if present) is the VL-2 or contains the same (B) The antigen B is human CD28, the VH-B is the VH-1 or contains the same, and / or the VL-B (if present) is the VL-1 or contains the same. (C) The antigen C is the third antigen, the VH-C is the VH-3 or contains the VH-3, and / or the VL-C (if present) is the VL-3 or contains the VL-3. (IV)(A) The antigen A is the second antigen, the VH-A is the VH-2 or contains the same, and / or the VL-A (if present) is the VL-2 or contains the same (B) The antigen B is the third antigen, the VH-B is the VH-3 or contains the same, and / or the VL-B (if present) is the VL-3 or contains the same. (C) The antigen C is human CD28, the VH-C is the VH-1, or contains the VH-1, and / or the VL-C (if present) is the VL-1, or contains the VL-1. (V)(A) The antigen A is the third antigen, the VH-A is the VH-3 or contains the same, and / or the VL-A (if present) is the VL-3 or contains the same (B) The antigen B is human CD28, the VH-B is the VH-1 or contains the same, and / or the VL-B (if present) is the VL-1 or contains the same. (C) The antigen C is the second antigen, the VH-C is the VH-2 or contains the same, and / or the VL-C (if present) is the VL-2 or contains the same, (VI)(A) The antigen A is the third antigen, the VH-A is the VH-3 or contains the same, and / or the VL-A (if present) is the VL-3 or contains the same (B) The antigen B is the second antigen, the VH-B is the VH-2 or contains the same, and / or the VL-B (if present) is the VL-2 or contains the same. (C) The multispecific antibody according to any one of claims 26 to 39, wherein the antigen C is human CD28, the VH-C is the VH-1 or comprises the same, and / or the VL-C (if present) is the VL-1 or comprises the same.

63. (D) At least one antigen-binding region (ABR-D) that binds to antigen D, (D-1) A Fab (Fab-D) that binds to antigen D, (D-1-i) Heavy chain D, comprising a heavy chain variable domain D (VH-D) and a heavy chain steady region D (CH-D) which includes at least a heavy chain steady domain 1D (CH1-D), and (D-ii) Light chain D, comprising a variable light chain domain D (VL-D) and a constant light chain domain D (CL-D), The heavy chain D and the light chain D are optionally paired with each other via at least one disulfide bond, and Fab (Fab-D) is bound to antigen D. (D-2) scFv (scFv-D) that binds to antigen D, (D-i) Heavy chain variable domain D (VH-D), and (D-ii) Light chain variable domain D (VL-D), (a) The C-terminus of the VH-D is connected to the N-terminus of the VL-D, and optionally the scFv-D includes the VH-D, linker, and VL-D from the N-terminus to the C-terminus, or (b) The C-terminus of the VL-D is linked to the N-terminus of the VH-D, and optionally the scFv-D contains the VL-D, a linker, and the VH-D, and is an scFv (scFv-D) that binds to antigen D, from the N-terminus to the C-terminus. (D-3) scFab (scFab-D) that binds to antigen D, (D-i) Heavy chain variable domain D (VH-D), and heavy chain steady region D (CH-D) which includes at least heavy chain steady domain 1D (CH1-D), and (D-ii) Light chain D, comprising a variable light chain domain D (VL-D) and a constant light chain domain D (CL-D), (a) The C-terminus of the heavy chain D is connected to the N-terminus of the light chain D, and optionally the scFab-D includes the heavy chain D, a linker, and the light chain D from the N-terminus to the C-terminus, or (b) The C-terminus of the light chain D is linked to the N-terminus of the heavy chain D, and optionally the scFab-D is an scFab that binds to antigen D, comprising the light chain D, a linker, and the heavy chain D from the N-terminus to the C-terminus, or (D-4) Further comprising at least one antigen-binding region (ABR-D) that binds to antigen D, including an sdAb (sdFab-D) that binds to antigen D, which contains a heavy chain variable domain D (VH-D), Furthermore, optionally, the multispecific antibody includes a structure optionally according to one of Figures 2 to 6, as shown in one of Figures 1 to 6. A multispecific antibody according to any one of claims 60 to 62, wherein, optionally, antigen D is the same as or different from antigen A, antigen B, and / or antigen C.

64. In (D-1), Fab-D is associated with or connected to ABR-A, ABR-B, and / or ABR-C, and optionally, (a) The heavy chain D, optionally the C-terminus or N-terminus of the heavy chain D, is associated or linked to the ABR-A, the ABR-B, and / or the ABR-C, optionally the C-terminus and / or N-terminus of the heavy chain A and / or the light chain A (if present) of the ABR-A, the heavy chain B (if present) and / or the light chain B (if present) of the ABR-B, the scFv-B (if present), the scFab-B (if present), or the sdAb-B (if present) is associated or linked to the C-terminus and / or N-terminus of the heavy chain C (if present) and / or the light chain C (if present) of the ABR-C, the scFv-C (if present), the scFab-C (if present), or the sdAb-C (if present) is associated or linked to the C-terminus and / or N-terminus of the heavy chain C (if present) and / or the light chain C (if present) of the ABR-C, and / or (a) The light chain D, optionally the C-terminus or N-terminus of the light chain C, is associated or linked to the ABR-A, the ABR-B, and / or the ABR-C, optionally the C-terminus and / or N-terminus of the heavy chain A of the ABR-A and / or the light chain A (if present), the heavy chain B of the ABR-B (if present) and / or the light chain B (if present), the scFv-B (if present), the scFab-B (if present), or the sdAb-B (if present), is associated or linked to the C-terminus and / or N-terminus of the heavy chain C of the ABR-C (if present) and / or the light chain C (if present), the scFv-C (if present), the scFab-C (if present), or the sdAb-C (if present), is associated or linked to the C-terminus and / or N-terminus of the heavy chain C of the ABR-C (if present) and / or the light chain C (if present), the scFv-C (if present), the scFab-C (if present), or the sdAb-C (if present), is associated or linked to the C-terminus and / or N-terminus of the heavy chain C of the ABR-C (if present), optionally via a linker. In (D-2), the scFv-D, optionally the C-terminus or N-terminus of the scFv-D, is associated with or linked to the ABR-A, the ABR-B, and / or the ABR-C, optionally the C-terminus and / or N-terminus of the heavy chain A and / or the light chain A (if present) of the ABR-A, the heavy chain B (if present) and / or the light chain B (if present) of the ABR-B, and the scFv-B (if present) ), the C-terminus and / or the N-terminus of scFab-B (if present) or sdAb-B (if present), and / or the heavy chain C (if present) and / or the light chain C (if present), scFv-C (if present), scFab-C (if present), or sdAb-C (if present), are optionally associated or linked via a linker. In (D-3), the scFab-D, optionally the C-terminus or N-terminus of the scFab-D, is associated with or linked to the ABR-A, the ABR-B, and / or the ABR-C, optionally the C-terminus and / or N-terminus of the heavy chain A and / or light chain A (if present) of the ABR-A, the heavy chain B (if present) and / or light chain B (if present) of the ABR-B, and the scFv-B (if present) The C-terminus and / or N-terminus of scFab-B (if present) or sdAb-B (if present), and / or the heavy chain C (if present) and / or light chain C (if present) of ABR-C, the C-terminus and / or N-terminus of scFv-C (if present), the scFab-C (if present) or sdAb-C (if present), are optionally associated or linked via a linker, or In (D-4), the sdFab-D, optionally the C-terminus or N-terminus of the sdFab-D, is associated with or linked to the ABR-A, the ABR-B, and / or the ABR-C, optionally the C-terminus and / or N-terminus of the heavy chain A and / or the light chain A (if present) of the ABR-A, the heavy chain B (if present) and / or the light chain B (if present) of the ABR-B, and the scFv-B (if present) If, in the case of, the C-terminus and / or N-terminus of scFab-B (if present) or sdAb-B (if present), and / or the heavy chain C (if present) and / or the light chain C (if present), scFv-C (if present), scFab-C (if present), or sdAb-C (if present), are optionally associated or linked via a linker. The multispecific antibody according to claim 63, wherein optionally, the optionally selected linker in (D-1), (D-2), (D-3), and / or (D-4) is a peptide linker, or optionally a flexible peptide linker.

65. (I) (A) The antigen A is human CD28, the VH-A is the VH-1 or contains the same, and / or the VL-A (if present) is the VL-1 or contains the same. (B) The antigen B is the second antigen, the VH-B is the VH-2 or contains the same, and / or the VL-B (if present) is the VL-2 or contains the same. (C) The antigen C is the third antigen, the VH-C is the VH-3 or contains the same, and / or the VL-C (if present) is the VL-3 or contains the same. (D) The antigen D is the fourth antigen, the VH-D is the VH-4 or contains the VH-4, and / or the VL-D (if present) is the VL-4 or contains the VL-4. (II) (A) The antigen A is human CD28, the VH-A is the VH-1 or contains the same, and / or the VL-A (if present) is the VL-1 or contains the same (B) The antigen B is the second antigen, the VH-B is the VH-2 or contains the same, and / or the VL-B (if present) is the VL-2 or contains the same. (C) The antigen C is the fourth antigen, the VH-C is the VH-4 or contains the same, and / or the VL-C (if present) is the VL-4 or contains the same. (D) The antigen D is the third antigen, the VH-D is the VH-3 or contains the VH-3, and / or the VL-D (if present) is the VL-3 or contains the VL-3. (III) (A) The antigen A is human CD28, the VH-A is the VH-1 or contains the same, and / or the VL-A (if present) is the VL-1 or contains the same (B) The antigen B is the third antigen, the VH-B is the VH-3 or contains the same, and / or the VL-B (if present) is the VL-3 or contains the same. (C) The antigen C is the second antigen, the VH-C is the VH-2 or contains the same, and / or the VL-C (if present) is the VL-2 or contains the same. (D) The antigen D is the fourth antigen, the VH-D is the VH-4 or contains the VH-4, and / or the VL-D (if present) is the VL-4 or contains the VL-4. (IV)(A) The antigen A is human CD28, the VH-A is the VH-1 or contains the same, and / or the VL-A (if present) is the VL-1 or contains the same. (B) The antigen B is the third antigen, the VH-B is the VH-3 or contains the same, and / or the VL-B (if present) is the VL-3 or contains the same. (C) The antigen C is the fourth antigen, the VH-C is the VH-4 or contains the same, and / or the VL-C (if present) is the VL-4 or contains the same. (D) The antigen D is the second antigen, the VH-D is the VH-2 or contains the VH-2, and / or the VL-D (if present) is the VL-2 or contains the VL-2. (V)(A) The antigen A is human CD28, the VH-A is the VH-1 or contains the same, and / or the VL-A (if present) is the VL-1 or contains the same. (B) The antigen B is the fourth antigen, the VH-B is the VH-4 or contains the VH-4, and / or the VL-B (if present) is the VL-4 or contains the VL-4. (C) The antigen C is the second antigen, the VH-C is the VH-2 or contains the same, and / or the VL-C (if present) is the VL-2 or contains the same. (D) The antigen D is the third antigen, the VH-D is the VH-3 or contains the VH-3, and / or the VL-D (if present) is the VL-3 or contains the VL-3. (VI)(A) The antigen A is human CD28, the VH-A is the VH-1 or contains the same, and / or the VL-A (if present) is the VL-1 or contains the same. (B) The antigen B is the fourth antigen, the VH-B is the VH-4 or contains the VH-4, and / or the VL-B (if present) is the VL-4 or contains the VL-4. (C) The antigen C is the third antigen, the VH-C is the VH-3 or contains the same, and / or the VL-C (if present) is the VL-3 or contains the same. (D) The antigen D is the second antigen, the VH-D is the VH-2 or contains the VH-2, and / or the VL-D (if present) is the VL-2 or contains the VL-2. (VII) (A) The antigen A is the second antigen, the VH-A is the VH-2 or contains the same, and / or the VL-A (if present) is the VL-2 or contains the same (B) The antigen B is human CD28, the VH-B is the VH-1 or contains the same, and / or the VL-B (if present) is the VL-1 or contains the same. (C) The antigen C is the third antigen, the VH-C is the VH-3 or contains the same, and / or the VL-C (if present) is the VL-3 or contains the same. (D) The antigen D is the fourth antigen, the VH-D is the VH-4 or contains the VH-4, and / or the VL-D (if present) is the VL-4 or contains the VL-4. (VIII) (A) The antigen A is the second antigen, the VH-A is the VH-2 or contains the same, and / or the VL-A (if present) is the VL-2 or contains the same (B) The antigen B is human CD28, the VH-B is the VH-1 or contains the same, and / or the VL-B (if present) is the VL-1 or contains the same. (C) The antigen C is the fourth antigen, the VH-C is the VH-4 or contains the same, and / or the VL-C (if present) is the VL-4 or contains the same. (D) The antigen D is the third antigen, the VH-D is the VH-3 or contains the VH-3, and / or the VL-D (if present) is the VL-3 or contains the VL-3. (IX)(A) The antigen A is the second antigen, the VH-A is the VH-2 or contains the same, and / or the VL-A (if present) is the VL-2 or contains the same. (B) The antigen B is the third antigen, the VH-B is the VH-3 or contains the same, and / or the VL-B (if present) is the VL-3 or contains the same. (C) The antigen C is human CD28, the VH-C is the VH-1 or contains the same, and / or the VL-C (if present) is the VL-1 or contains the same. (D) The antigen D is the fourth antigen, the VH-D is the VH-4 or contains the VH-4, and / or the VL-D (if present) is the VL-4 or contains the VL-4. (X)(A) The antigen A is the second antigen, the VH-A is the VH-2 or contains the same, and / or the VL-A (if present) is the VL-2 or contains the same. (B) The antigen B is the third antigen, the VH-B is the VH-3 or contains the same, and / or the VL-B (if present) is the VL-3 or contains the same. (C) The antigen C is the fourth antigen, the VH-C is the VH-4 or contains the same, and / or the VL-C (if present) is the VL-4 or contains the same. (D) The antigen D is human CD28, the VH-D is the VH-1 or contains the VH-1, and / or the VL-D (if present) is the VL-1 or contains the VL-1. (XI)(A) The antigen A is the second antigen, the VH-A is the VH-2 or contains the VH-2, and / or the VL-A (if present) is the VL-2 or contains the VL-2, (B) The antigen B is the fourth antigen, the VH-B is the VH-4 or contains the VH-4, and / or the VL-B (if present) is the VL-4 or contains the VL-4. (C) The antigen C is human CD28, the VH-C is the VH-1 or contains the same, and / or the VL-C (if present) is the VL-1 or contains the same. (D) The antigen D is the third antigen, the VH-D is the VH-3 or contains the VH-3, and / or the VL-D (if present) is the VL-3 or contains the VL-3. (XII) (A) The antigen A is the second antigen, the VH-A is the VH-2 or contains the same, and / or the VL-A (if present) is the VL-2 or contains the same (B) The antigen B is the fourth antigen, the VH-B is the VH-4 or contains the VH-4, and / or the VL-B (if present) is the VL-4 or contains the VL-4. (C) The antigen C is the third antigen, the VH-C is the VH-3 or contains the same, and / or the VL-C (if present) is the VL-3 or contains the same. (D) The antigen D is human CD28, the VH-D is the VH-1 or contains the VH-1, and / or the VL-D (if present) is the VL-1 or contains the VL-1. (XIII) (A) The antigen A is the third antigen, the VH-A is the VH-3 or contains the same, and / or the VL-A (if present) is the VL-3 or contains the same (B) The antigen B is human CD28, the VH-B is the VH-1 or contains the same, and / or the VL-B (if present) is the VL-1 or contains the same. (C) The antigen C is the second antigen, the VH-C is the VH-2 or contains the same, and / or the VL-C (if present) is the VL-2 or contains the same. (D) The antigen D is the fourth antigen, the VH-D is the VH-4 or contains the VH-4, and / or the VL-D (if present) is the VL-4 or contains the VL-4. (XIV)(A) The antigen A is the third antigen, the VH-A is the VH-3 or contains the same, and / or the VL-A (if present) is the VL-3 or contains the same (B) The antigen B is human CD28, the VH-B is the VH-1 or contains the same, and / or the VL-B (if present) is the VL-1 or contains the same. (C) The antigen C is the fourth antigen, the VH-C is the VH-4 or contains the same, and / or the VL-C (if present) is the VL-4 or contains the same. (D) The antigen D is the second antigen, the VH-D is the VH-2 or contains the VH-2, and / or the VL-D (if present) is the VL-2 or contains the VL-2. (XV)(A) The antigen A is the third antigen, the VH-A is the VH-3 or contains the same, and / or the VL-A (if present) is the VL-3 or contains the same (B) The antigen B is the second antigen, the VH-B is the VH-2 or contains the same, and / or the VL-B (if present) is the VL-2 or contains the same. (C) The antigen C is human CD28, the VH-C is the VH-1 or contains the same, and / or the VL-C (if present) is the VL-1 or contains the same. (D) The antigen D is the fourth antigen, the VH-D is the VH-4 or contains the VH-4, and / or the VL-D (if present) is the VL-4 or contains the VL-4. (XVI)(A) The antigen A is the third antigen, the VH-A is the VH-3 or contains the same, and / or the VL-A (if present) is the VL-3 or contains the same (B) The antigen B is the second antigen, the VH-B is the VH-2 or contains the same, and / or the VL-B (if present) is the VL-2 or contains the same. (C) The antigen C is the fourth antigen, the VH-C is the VH-4 or contains the same, and / or the VL-C (if present) is the VL-4 or contains the same. (D) The antigen D is human CD28, the VH-D is the VH-1 or contains the VH-1, and / or the VL-D (if present) is the VL-1 or contains the VL-1. (XVII) (A) The antigen A is the third antigen, the VH-A is the VH-3 or contains the same, and / or the VL-A (if present) is the VL-3 or contains the same (B) The antigen B is the fourth antigen, the VH-B is the VH-4 or contains the VH-4, and / or the VL-B (if present) is the VL-4 or contains the VL-4. (C) The antigen C is human CD28, the VH-C is the VH-1 or contains the same, and / or the VL-C (if present) is the VL-1 or contains the same. (D) The antigen D is the second antigen, the VH-D is the VH-2 or contains the VH-2, and / or the VL-D (if present) is the VL-2 or contains the VL-2. (XVIII) (A) The antigen A is the third antigen, the VH-A is the VH-3 or contains the same, and / or the VL-A (if present) is the VL-3 or contains the same (B) The antigen B is the fourth antigen, the VH-B is the VH-4 or contains the VH-4, and / or the VL-B (if present) is the VL-4 or contains the VL-4. (C) The antigen C is the second antigen, the VH-C is the VH-2 or contains the same, and / or the VL-C (if present) is the VL-2 or contains the same. (D) The antigen D is human CD28, the VH-D is the VH-1 or contains the VH-1, and / or the VL-D (if present) is the VL-1 or contains the VL-1. (IXX)(A) The antigen A is the fourth antigen, the VH-A is the VH-4 or contains the same, and / or the VL-A (if present) is the VL-4 or contains the same. (B) The antigen B is human CD28, the VH-B is the VH-1 or contains the same, and / or the VL-B (if present) is the VL-1 or contains the same. (C) The antigen C is the second antigen, the VH-C is the VH-2 or contains the same, and / or the VL-C (if present) is the VL-2 or contains the same. (D) The antigen D is the third antigen, the VH-D is the VH-3 or contains the VH-3, and / or the VL-D (if present) is the VL-3 or contains the VL-3. (XX)(A) The antigen A is the fourth antigen, the VH-A is the VH-4 or contains the same, and / or the VL-A (if present) is the VL-4 or contains the same. (B) The antigen B is human CD28, the VH-B is the VH-1 or contains the same, and / or the VL-B (if present) is the VL-1 or contains the same. (C) The antigen C is the third antigen, the VH-C is the VH-3 or contains the same, and / or the VL-C (if present) is the VL-3 or contains the same. (D) The antigen D is the second antigen, the VH-D is the VH-2 or contains the VH-2, and / or the VL-D (if present) is the VL-2 or contains the VL-2. (XXI)(A) The antigen A is the fourth antigen, the VH-A is the VH-4 or contains the VH-4, and / or the VL-A (if present) is the VL-4 or contains the VL-4, (B) The antigen B is the second antigen, the VH-B is the VH-2 or contains the same, and / or the VL-B (if present) is the VL-2 or contains the same. (C) The antigen C is human CD28, the VH-C is the VH-1 or contains the same, and / or the VL-C (if present) is the VL-1 or contains the same. (D) The antigen D is the third antigen, the VH-D is the VH-3 or contains the VH-3, and / or the VL-D (if present) is the VL-3 or contains the VL-3. (XXII) (A) The antigen A is the fourth antigen, the VH-A is the VH-4 or contains the same, and / or the VL-A (if present) is the VL-4 or contains the same (B) The antigen B is the second antigen, the VH-B is the VH-2 or contains the same, and / or the VL-B (if present) is the VL-2 or contains the same. (C) The antigen C is the third antigen, the VH-C is the VH-3 or contains the same, and / or the VL-C (if present) is the VL-3 or contains the same. (D) The antigen D is human CD28, the VH-D is the VH-1 or contains the VH-1, and / or the VL-D (if present) is the VL-1 or contains the VL-1. (XXIII) (A) The antigen A is the fourth antigen, the VH-A is the VH-4 or contains the same, and / or the VL-A (if present) is the VL-4 or contains the same (B) The antigen B is the third antigen, the VH-B is the VH-3 or contains the same, and / or the VL-B (if present) is the VL-3 or contains the same. (C) The antigen C is human CD28, the VH-C is the VH-1 or contains the same, and / or the VL-C (if present) is the VL-1 or contains the same. (D) The antigen D is the second antigen, the VH-D is the VH-2 or contains the VH-2, and / or the VL-D (if present) is the VL-2 or contains the VL-2, or (XXIV)(A) The antigen A is the fourth antigen, the VH-A is the VH-4 or contains the same, and / or the VL-A (if present) is the VL-4 or contains the same (B) The antigen B is the third antigen, the VH-B is the VH-3 or contains the same, and / or the VL-B (if present) is the VL-3 or contains the same. (C) The antigen C is the second antigen, the VH-C is the VH-2 or contains the same, and / or the VL-C (if present) is the VL-2 or contains the same. (D) The multispecific antibody according to any one of claims 40 to 53, wherein the antigen D is human CD28, the VH-D is or contains the VH-1, and / or the VL-D (if present) is or contains the VL-1.

66. (I) Figure 2C (upper left), 2F, 2G (inside the box), 2J (inside the box), 2K (inside the box), 2J, and / or 2M (optionally, antigen A and antigen B are CD28 and CD3, or CD3 and CD28, respectively), (II) Choose any one of Figures 3A to 3B (optionally, (a) Whether antigen A and antigen B are CD28 and CD3, respectively, or CD3 and CD28, (b) Antigen A and Antigen C are CD28 and CD3, respectively, or CD3 and CD28, (c) Antigen B and Antigen C are CD28 and CD3, respectively, or CD3 and CD28, respectively. (III) Any one of Figures 4A-4C, 5A (inside the box), 5C-5F, 5H (top left), 5I (top left), and / or 5J-5M (optionally selected, (a) Whether antigen A and antigen B are CD28 and CD3, respectively, or CD3 and CD28, (b) Whether antigen A and antigen C are CD28 and CD3, respectively, or CD3 and CD28, (c) Whether antigen A and antigen D are CD28 and CD3, respectively, or CD3 and CD28, (d) Whether the antigen B and the antigen C are CD28 and CD3, respectively, or CD3 and CD28, (e) Antigen B and Antigen D are CD28 and CD3, respectively, or CD3 and CD28, (f) The multispecific antibody according to any one of claims 12 to 65, comprising the structure shown in (f) the antigen C and the antigen D being CD28 and CD3, or CD3 and CD28, respectively.

67. Monovalent, divalent, trivalent, or tetravalent, (a) Human differentiation cluster 3 (CD3), (b) Cancer antigen, optionally TSA or TAA, (c) Human CD28, (d) Any one of the antigens selected from those listed in Table 3, and / or (e) A multispecific antibody according to any one of claims 12 to 66, which binds to any one of the cancer antigens selected from those listed in Table 3, and optionally to any one of the TSAs or any one of the TAAs.

68. A multispecific antibody according to claim 67, which binds bivalently to CD3.

69. VH-1 coding nucleic acids having at least about 80%, at least about 85%, at least about 90%, at least about 91%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, at least about 99%, or 100% identity to any one of the VH coding sequences of Table 2A and / or 13A, or any one of the VH coding sequences of sequence numbers 119, 2119, 2819, 4619, 5719, 6119, 6819, 7019, or 8319, and / or The VL-1 coding nucleic acid optionally contains at least about 80%, at least about 85%, at least about 90%, at least about 91%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, at least about 99%, or 100% identity with any one of the VL coding sequences of Table 2A and / or 13A, including at least about 80%, at least about 85%, at least about 90%, at least about 91%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, at least about 99%, or 100% identity with any one of the VL coding sequences of sequence numbers 129, 2129, 2829, 4629, 5729, 6129, or 6829. A nucleic acid encoding a VH-1 coding nucleic acid and a VL-1 coding nucleic acid, further optionally comprising a VH-1 coding nucleic acid comprising SEQ ID NOs: 119 and 129, SEQ ID NOs: 2119 and 2129, SEQ ID NOs: 2819 and 2829, SEQ ID NOs: 4619 and 4629, SEQ ID NOs: 5719 and 5729, SEQ ID NOs: 6119 and 6129, or SEQ ID NOs: 6819 and 6829, respectively, or comprising a VH-1 coding nucleic acid comprising SEQ ID NOs: 7019 or 8319, according to any one of claims 1 to 11, or a nucleic acid encoding a multispecific antibody or a portion thereof, according to any one of claims 12 to 68.

70. Optionally, (i) is an expression vector and / or (ii) A nucleic acid-containing vector according to claim 69, comprising a plasmid, a viral vector (optionally adenovirus, lentivirus, or retrovirus), a lipid-based vector, a self-replicating RNA vector, a virus-like particle, a polymer-based vector, and / or nanoparticles, optionally lipid-based nanoparticles.

71. Isolated, recombinant, and / or host cells comprising the nucleic acid described in claim 69 and / or the vector described in claim 70, wherein the isolated, recombinant, and / or host cells are optionally, (i) Non-mammalian, optionally, bacteria, yeast, fungi, protozoa, plants, or insects, or (ii) Isolated, recombinant, and / or host cells of a mammal, which is optionally human, non-human primate, monkey, rabbit, rodent, hamster, rat, or mouse.

72. At least one excipient, An anti-human CD28 antibody or antigen-binding antibody fragment according to any one of claims 1 to 11, or a multispecific antibody according to any one of claims 12 to 68, The nucleic acid according to claim 69, The vector according to claim 70, and A composition comprising at least one of the isolated, recombinant, and / or host cells described in claim 71.

73. A method for treating a disease, disorder, or condition in a subject, wherein the method involves providing an effective amount of the subject. An anti-human CD28 antibody or antigen-binding antibody fragment according to any one of claims 1 to 11, or a multispecific antibody according to any one of claims 12 to 68, The nucleic acid according to claim 69, The vector according to claim 70, The isolated, recombinant, and / or host cell according to claim 71, and / or The method includes administering at least one of the compositions described in claim 72. Optionally, (a) The subject is, (i) Mammals, optionally including humans, non-human primates, monkeys, horses, cattle, sheep, goats, pigs, dogs, cats, rabbits, rodents, hamsters, rats, or mice, (ii) Non-mammalian vertebrates, optionally birds, fish, amphibians, or reptiles, and / or (b) A method further comprising administering an additional drug, optionally an adjuvant or therapeutic agent, to the subject.

74. The aforementioned disease, disorder, or condition includes cancer or neoplasm, autoimmune disease, neurodegenerative disease, infectious disease, inflammatory disease, or another disease, and is optionally, (i) The cancer described above, (i-1) A solid tumor selected at random from one or more of the following: mesothelioma, malignant pleural mesothelioma, non-small cell lung cancer, small cell lung cancer, squamous cell carcinoma of the lung, large cell lung cancer, pancreatic cancer, pancreatic ductal adenocarcinoma, esophageal adenocarcinoma, breast cancer, glioblastoma, ovarian cancer, colorectal cancer, prostate cancer, cervical cancer, skin cancer, melanoma, kidney cancer, liver cancer, brain cancer, thymoma, sarcoma, carcinoma, uterine cancer, kidney cancer, gastrointestinal cancer, urothelial carcinoma, pharyngeal cancer, head and neck cancer, rectal cancer, esophageal cancer, or bladder cancer, or its metastases, and / or (i-2) Selectively include chronic lymphocytic leukemia (CLL), mantle cell lymphoma (MCL), multiple myeloma, acute lymphoblastic leukemia (ALL), Hodgkin lymphoma, B-cell acute lymphoblastic leukemia (BALL), T-cell acute lymphoblastic leukemia (TALL), small lymphocytic leukemia (SLL), B-cell prolymphocytic leukemia, blastocyte plasmacytoid dendritic cell neoplasm, Burkitt lymphoma, and diffuse lymphoma. Large B-cell lymphoma (DLBCL), DLBCL associated with chronic inflammation, chronic myeloid leukemia, myeloproliferative disorders, follicular lymphoma, pediatric follicular lymphoma, hairy cell leukemia, small cell or large cell follicular lymphoma, malignant lymphoproliferative state, MALT lymphoma (extra-marginal zone lymphoma of mucosa-associated lymphoid tissue), marginal zone lymphoma, spinal dysplasia, myelodysplastic syndrome, non-Hodgkin Lymphoma, plasmablastic lymphoma, plasmacytoid dendritic cell neoplasm, Waldenström's hypergammaglobulinemia, perisplenic zone lymphoma, splenic lymphoma / leukemia, diffuse red medullary small cell B-cell lymphoma of the spleen, hairy cell leukemia variant, lymphoplasmacytic lymphoma, heavy chain disease, plasmacytomyeloma, solitary plasmacytoma of bone, extraskeletal plasmacytoma, nodular marginal zone lymphoma, pediatric nodular marginal zone lymphoma Lymphoma is a humoral cancer selected from primary cutaneous follicular lymphoma, lymphomatoid granulomatosis, primary mediastinal (thymic) large B-cell lymphoma, intravascular large B-cell lymphoma, ALK+ large B-cell lymphoma, large B-cell lymphoma arising from HHV8-associated multicentric Castleman disease, primary humoral lymphoma, B-cell lymphoma, acute myeloid leukemia (AML), or lymphoma that cannot be classified. (ii) The autoimmune disease or inflammatory disease is psoriasis, rheumatoid arthritis, autoimmune arthritis, type 1 diabetes, systemic lupus erythematosus, myasthenia gravis, multiple sclerosis, scleroderma, inflammatory bowel disease, Crohn's disease, ulcerative colitis, Guillain-Barré syndrome, chronic inflammatory demyelinating polyneuropathy, pemphigus vulgaris, Sjögren's syndrome, Addison's disease, Behçet's disease, Schmidt's syndrome, celiac disease, dermatomyositis, autoimmune vitiligo, Graves' disease, Hashimoto's thyroiditis, Kawasaki disease, pernicious anemia, autoimmune vasculitis, or fibrosis. (iii) The neurodegenerative diseases are Alzheimer's disease, Huntington's disease, Parkinson's disease, amyotrophic lateral sclerosis, Friedreich's ataxia, Lewy body dementia, spinal muscular atrophy, motor neuron disease, multiple sclerosis, Batten disease, and Creutzfeldt-Jakob disease. (iv) The infectious disease is a viral disease, bacterial disease, fungal disease, yeast disease, protozoan disease, prion disease, or parasitic disease, and optionally (1) the viral disease is human immunodeficiency virus (HIV), hepatitis virus (optionally, hepatitis A, B, or C), human papillomavirus (HPV), herpes simplex virus (HSV) (optionally, HSV-1 or HSV-2), enterovirus, human cytomegalovirus, adenovirus, rhinovirus, poxvirus, influenza virus, coronavirus (optionally, MERS-CoV, SARS-CoV, SARS-CoV-2, or common human coronavirus), norovirus, West Nile virus, The method according to claim 73, wherein the bacterial disease is a Zika virus, poliovirus, Ebola virus, or dengue virus (DENV) infection, and (2) the bacterial disease is Salmonella, Escherichia coli, Mycobacterium tuberculosis, methicillin-resistant Staphylococcus aureus (MRSA), Clostridium difficile, Streptococcus pneumoniae, Klebsiella pneumoniae, Pseudomonas aeruginosa, Helicobacter pylori, Neisseria gonorrhoeae, Vibrio vulnificus, and / or (3) the fungal disease is aspergillosis, candidiasis, Candida auris infection, Cryptococcus neoformans infection, Pneumocystis irovecii infection, mucormycosis, talaromycetis, tinea, blastomycosis, coccidioidomycosis, Cryptococcus gattii infection, histoplasmosis, paracoccidioidomycosis, or sporotrichosis.

75. A method for producing an anti-human CD28 antibody or antigen-binding antibody fragment according to any one of claims 1 to 11, or a multispecific antibody according to any one of claims 12 to 68, (a) Culturing cells containing the nucleic acid described in claim 69 under conditions that enable the expression of the antibody or antigen-binding antibody fragment or the multispecific antibody, (b) A method comprising recovering the antibody or antigen-binding antibody fragment or the multispecific antibody from the cell culture from (a) and purifying it.

76. A method for isolating, recombining, and / or producing host cells or populations of such cells according to claim 71, comprising introducing the nucleic acid according to claim 69 and / or the vector according to claim 70 into one or more cells, wherein the introduction occurs in vitro, ex vivo, or in vivo.

77. An anti-human CD28 antibody or antigen-binding antibody fragment according to any one of claims 1 to 11, or a multispecific antibody according to any one of claims 12 to 68, a nucleic acid according to claim 69, a vector according to claim 70, an isolated, recombinant, and / or host cell or population of such cells according to claim 71, or a composition according to claim 72.

78. For use in the treatment of a disease, disorder, or condition, optionally comprising one or more of the diseases, disorders, or conditions described in claim 74, an anti-human CD28 antibody or antigen-binding antibody fragment according to any one of claims 1 to 11, or a multispecific antibody according to any one of claims 12 to 68, a nucleic acid according to claim 69, a vector according to claim 70, an isolated, recombinant, and / or host cell or population of such cells according to claim 71, or a composition according to claim 72.

79. Use for the manufacture of a pharmaceutical product for the treatment of a disease, disorder, or condition, optionally comprising one or more of the diseases, disorders, or conditions described in claim 74, an anti-human CD28 antibody or antigen-binding antibody fragment according to any one of claims 1 to 11, or a multispecific antibody according to any one of claims 12 to 68, a nucleic acid according to claim 69, a vector according to claim 70, an isolated, recombinant, and / or host cell or population of such cells according to claim 71, or a composition according to claim 72.

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