56 results about "Antibody constant region" patented technology

The present inventors succeeded in improving the antibody constant region to have increased stability under acid conditions, reduced heterogeneity originated from disulfide bonds in the hinge region, reduced heterogeneity originated from the H chain C terminus, and increased stability at high concentrations as well as in discovering novel constant region sequences having reduced Fcγ receptor-binding, while minimizing the generation of novel T-cell epitope peptides. As a result, the present inventors successfully discovered antibody constant regions with improved physicochemical properties (stability and homogeneity), immunogenicity, safety, and pharmacokinetics.

Disclosed are a CH3 domain variant pair of an antibody, a method for preparing same, and a use thereof. A mutation is induced in the CH3 domain so as to improve a yield of forming a heterodimer heavy chain constant region of an antibody. The CH3 domain heterodimer forms a heterodimer heavy chain constant region with a high efficiency of 90 to 95% or more and also has outstanding heat stability. A heterodimer heavy chain constant region including the CH3 domain heterodimer can construct a bispecific monoclonal antibody which simultaneously recognizes two kinds of antigens. The CH3 domain heterodimer and the bispecific antibody or fusion protein of an antibody constant region comprising same can be usefully applied to the treatment or prevention of a disease associated with a target antigen or a target protein.

This invention provides an agonist antibody to a human thrombopoietin receptor (alias: human c-Mpl). More particularly, this invention provides an agonist antibody to a human thrombopoietin receptor, wherein the agonist antibody comprises: antibody constant regions comprising (1) amino acid sequences in a heavy chain constant region and a light chain constant region of a human antibody, (2) an amino acid sequence of a heavy chain constant region with a domain substituted between human antibody subclasses, and an amino acid sequence of a light chain constant region of a human antibody, or (3) amino acid sequences comprising a deletion(s), substitution(s), addition(s), or insertion(s) of one or several amino acid residues in the amino acid sequences of (1) or (2) above; and antibody variable regions capable of binding to and activating a human thrombopoietin receptor; and wherein the agonist antibody has the properties: (a) that the antibody induces colony formation at a concentration of 10,000 ng/ml or lower as determined by the CFU-MK colony formation assay using human umbilical-cord-blood-derived CD34+ cells; and (b) that the antibody has a maximal activity at least 50% higher than that of PEG-rHuMGDF and an 50% effective concentration (EC50) of 100 nM or less in the cell proliferation assay using UT7/TPO cell. Also provided is a pharmaceutical composition for treating thrombocytopenia comprising said antibody.

The present invention is directed to antibodies, and antigen-binding portions thereof, engineered to introduce amino acids for site-specific conjugation. The invention relates to engineered antibody constant region (Fc, Cγ, Cκ, and Cλ) polypeptides, and portions thereof, and antibodies comprising the polypeptides. Further, the invention relates to Fc fusion proteins comprising an engineered Fc region. The invention also relates to methods and uses of the engineered antibodies and portions for, among other things, production of antibody-drug conjugate therapeutics.

A fusion protein for delivery of a wide variety of agents to a cell via antibody-receptor-mediated endocytosis comprises a first segment and a second segment: the first segment comprising a variable region of an antibody that recognizes an antigen on the surface of a cell that after binding to the variable region of the antibody undergoes antibody-receptor-mediated endocytosis, and, optionally, further comprises at least one domain of a constant region of an antibody; and the second segment comprising a protein domain selected from the group consisting of avidin, an avidin mutein, a chemically modified avidin derivative, streptavidin, a streptavidin mutein, and a chemically modified streptavidin derivative. Typically, the antigen is a protein. Typically, the protein antigen on the surface of the cell is a receptor such as a transferrin receptor-or an insulin receptor. The invention also includes an antibody construct incorporating the fusion protein that is either a heavy chain or a light chain together with a complementary light chain or heavy chain to form an intact antibody molecule. The invention further includes targeting methods and screening methods.

Provided are bispecific antibodies having a full-size antibody portion with two light chains and two heavy chains, wherein the two heavy chains each is fused to a single-chain variable fragment (scFv) portion. In certain embodiments, the full-size antibody has specificity to EGFR and the scFv has specificity to VEGF.

The present invention relates to one or more nucleic acid(s) encoding a binding molecule specifically binding to a human CD28 molecule, comprising (a) a nucleic acid sequence encoding a VH region and a nucleic acid sequence encoding a VL region comprising CDRs in a human immunoglobulin framework, wherein (i) the CDRs of the VH region (CDR-H) comprise the amino acid sequences of SEQ ID NOS: 2 or 18 (CDR-H3), 4 or 20 (CDR-H2) and 6 or 22 (CDR-H1) or are encoded by the nucleic acid sequences of SEQ ID NOS: 1 or 17 (CDR-H3), 3 or 19 (CDR-H2) and 5 or 21 (CDR-H1); and (ii) the CDRs of the VL region (CDR-L) comprise the amino acid sequences of SEQ ID NOS: 8 or 24 (CDR-L3), 10 or 26 (CDR-L2) and 12 or 28 (CDR-L1) or are encoded by the nucleic acid sequences of SEQ ID NOS: 7 or 23 (CDR-L3), 9 or 25 (CDR-L2) and 11 or 27 (CDR-L1); and (b) a nucleic acid sequence encoding the constant region of a human IgG1 or IgG4 antibody.

The present invention provides methods of creating and using OB protein compositions with an antibody constant region or portion thereof fused to an OB protein. The fusion protein is created by attaching the polyamino acids to the OB protein moiety. The fusion proteins can then be used for various therapeutic uses.

By altering amino acid sequences, the present inventors successfully produced constant regions that can confer antibodies with particularly favorable properties for pharmaceutical agents. When used to produce antibodies, the altered constant regions produced according to the present invention significantly reduce heterogeneity. Specifically, the antibody homogeneity can be achieved by using antibody heavy chain and light chain constant regions introduced with alterations provided by the present invention. More specifically, the alterations can prevent the loss of homogeneity of antibody molecules due to disulfide bond differences in the heavy chain. Furthermore, in a preferred embodiment, the present invention can improve antibody pharmacokinetics as well as prevent the loss of homogeneity due to C-terminal deletion in antibody constant region.

The present inventors devised methods for efficiently purifying bispecific antibodies using a chromatography column based on the difference in isoelectric points between the H chains of two types of antibodies, wherein the difference is introduced by modifying the amino acids present on the surface of the antibody variable regions of two types of antibodies that constitute a bispecific antibody. Furthermore, the inventors devised methods for efficiently purifying bispecific antibodies using a chromatography column by linking respective antigen binding sites (heavy chain variable regions) to the antibody constant regions having different isoelectric points, and then coexpressing these antibodies.

Methods of identifying and expressing an antibody variant are disclosed wherein the method comprises identifying a binding region in an antibody, fusing the binding region to a plurality of scaffolds of antibody constant regions to obtain antibody fragment variants, expressing the antibody fragment variants in organisms to form constructs and expressing the constructs carried by the organisms to form induced cultures, wherein the organisms are expressed in HTP mode.

The invention discloses an IgG-like long-acting immunological fusion protein and applications thereof. The IgG-like long-acting immunological fusion protein comprises an effector molecule and an IgG antibody constant region, wherein the effector molecule is linked to the IgG antibody constant region through a linker peptide, the effector molecule is a protein capable of exerting physiological functions in vivo, and the IgG antibody constant region is a structure obtained by removing two heavy chain variable regions and two light chain variable regions from an IgG antibody. According to the present invention, the IgG-like immunological fusion protein can effectively prolong the biological half-life of the protein drug (effector molecule) under the premise of the ensuring of the high affinity to the targeting molecule and the good in vivo activity, is far better than the similar Fc immunological fusion protein, and can be used for the treatment of diabetes, tumors, autoimmune diseases, endocrine and various diseases.

The invention provides a novel bispecific human IgG1 antibody, which comprises two kinds of Fc fragments with the same hinge regions, wherein the amino acid sequence of the hinge region is SEQ ID NO:1 or SEQ ID NO:28; the 216th to 230th site sequences in a natural human IgG1 antibody constant region are replaced. The amino acid position of the antibody constant region is determined according to EU numbering. In addition, the invention also provides a purpose of the bispecific antibody.

The invention belongs to the technical field of biology, and particularly relates to an IgG1Fc monomer and a preparation method and application thereof. In accordance with the sequence of a novel IgG1Fc monomer reformed in an antibody IgG1 constant region, through an antibody engineering technique, a human antibody IgG1 constant region Fc is reformed, so that an Fc dipolymer becomes an Fc monomer,an FcRn combination function is maintained, and an extremely low irrelevant protein non-specific combination characteristic is achieved; main features of the Fc monomer lie in that the Fc monomer hasmutation at positions of T366, L368, P395 and K409 in a CH3 region of the antibody constant region, has high-efficiency expression in prokaryotic cells, can use combination of a pH dependent specialcombination mode with FcRn, and has extremely low nonspecific combination characteristics. Through the novel Fc monomer, the IgG1Fc monomer can fuse or couple with various protein, polypeptide, micromolecules, nucleic acid and the like for different target points, so that fused or coupled molecules have the characteristic of combining pH dependence with FcRn.

Host cell lines for biopharmaceutical production of antibodies, antibody fragments or antibody-derived fusion proteins are selected as having the capability of inducing improved cellular effector functions, e.g., Fc-medicated effector functions. The host cells are derived from the rat myeloma cell line YB2/0 and are adapted to growth in chemically-defined medium.

The present invention discloses an agonistic antibody directed against human thrombopoietin receptor (also referred to as 'human c-Mpl). Specifically, the antibody has a constant region having a set of amino acid sequences selected from the following items (1) to (3): (1) amino acid sequences for a heavy-chain constant region and a light-chain constant region of a human antibody; (2) an amino acid sequence for a human antibody heavy-chain constant region in which the domain is replaced by one of other human antibody subclass and an amino acid sequence for a human antibody light-chain constant region; and (3) a set of amino acid sequences having the deletion, substitution, addition or insertion of one or several amino acid residues in each of the amino acid sequences shown in (1) and (2), and the antibody has a variable region capable of binding to a human thrombopoietin receptor to activate the receptor. The antibody also has the following properties: (a) the antibody can induce the formation of a colony at a concentration of 10,000 ng/mL or less in the CFU-MK colony formation assay using a human umbilical cord blood CD34+ cell; and (b) the antibody has the maximum activity higher than that of PEG-rHuMGDF by 50% or more and a 50% effective concentration (EC50) of 100 nM or less in the cell growth assay using an UT7/TPO cell. Also disclosed is a pharmaceutical composition for the treatment of thrombocytopenia, which comprises the antibody.

The invention discloses an anti-staphylococcus aureus alpha-hemolysin single-chain antibody scFv2 or scFv46, further discloses an anti-staphylococcus aureus alpha-hemolysin recombinant antibody scFv2-Fc or scFv46-Fc containing the scFv2 or scFv46 and a human antibody constant region Fc segment amino acid sequence, and further discloses a universal expression vector sp-Fc/pcDNA3.1 of the fully human anti-staphylococcus aureus alpha-hemolysin recombinant antibody. The nucleic acid sequence of an encoding gene of the universal expression vector is shown in SEQ ID No:13. The invention further discloses a eukaryotic expression vector of the fully human anti-staphylococcus aureus alpha-hemolysin recombinant antibody. The eukaryotic expression vector is obtained by inserting the single-chain antibody into the sp-Fc/pcDNA3.1. The invention further discloses a recombinant expression vector sp-scFv2-Fc/pMH3 or sp-scFv46-Fc/pMH3.