Abstract: A linker peptide for constructing a fusion protein. The linker peptide comprises a flexible peptide and a rigid peptide. The flexible peptide consists of one or more flexible units. The rigid peptide consists of one or more rigid units. The flexible unit comprises two or more amino acid residues selected from Gly, Ser, Ala, and Thr. The rigid unit comprises a human chorionic gonadotropin ?-subunit carboxy-terminal peptide (CTP) bearing a plurality of glycosylation sites. The linker peptide can more effectively eliminate mutual steric hindrance of two fusion molecules, decreasing a reduction/loss of polymerization or activity resulting from improper folding of an active protein or a conformational change. On the other hand, the negatively charged, highly sialylated CTP can resist renal clearance, further prolonging a half-life of a fused molecule and enhancing bioavailability of a fused protein.

Abstract: Provided by the present invention are an antibody against human TIM-3 or an antigen-binding fragment thereof, and further provided are a nucleic acid molecule encoding the antibody, an expression vector for expressing the antibody and a host cell, and a method for producing the antibody. Further provided by the present invention are a pharmaceutical composition comprising the antibody or an antigen-binding fragment of the antibody, and an application of the pharmaceutical composition in the preparation of a medicine, the medicine is used for preventing and/or treating various diseases (including tumors, infectious diseases and autoimmune diseases).

Abstract: A bispecific antibody, which specifically binds the surface antigen CD3 of immune cells and the BCMA antigen on the surface of tumor cells and which may bind to human CD3 with high affinity, induce T cell proliferation, and mediate tumor cell killing effects. The bispecific antibody may be used to mediate the T cell-specific killing of target cells in in vitro tests. The method for constructing a bispecific antibody is simple, and avoids the possibility of mismatching between two sets of light chains and heavy chains of a heterologous bispecific antibody, thus the difficulty of antibody purification is reduced, the affinity of the obtained antibody is high, the side effects of induced cytokines are few, and safety is high.

Abstract: A linker peptide for constructing a fusion protein. The linker peptide comprises a flexible peptide and a rigid peptide. The flexible peptide consists of one or more flexible units. The rigid peptide consists of one or more rigid units. The flexible unit comprises two or more amino acid residues selected from Gly, Ser, Ala, and Thr. The rigid unit comprises a human chorionic gonadotropin ?-subunit carboxy-terminal peptide (CTP) bearing a plurality of glycosylation sites. The linker peptide can more effectively eliminate mutual steric hindrance of two fusion molecules, decreasing a reduction/loss of polymerization or activity resulting from improper folding of an active protein or a conformational change. On the other hand, the negatively charged, highly sialylated CTP can resist renal clearance, further prolonging a half-life of a fused molecule and enhancing bioavailability of a fused protein.

Abstract: A tetravalent, homodimer-type bispecific antibody molecule that simultaneously targets immune effector cell antigen CD3 and human epidermal growth factor receptor 2 (Her2); the bispecific antibody molecule comprises, from in sequence from N-terminus to C-terminus, a first single-chain Fv capable of specifically binding to Her2, a second single-chain Fv capable of specifically binding to CD3, and an Fc fragment; the first and second single-chain Fv are connected by means of a connection peptide, and the second single-chain Fv is connected to the Fc directly fragment or is connected by means of a connection peptide; the Fc fragment does not have effector functions such as CDC, ADCC and ADCP. The bispecific antibody may significantly inhibit or kill tumor cells, and has controlled toxic side effects that may be caused by excessive activation of effector cells.

Abstract: A linker peptide for constructing a fusion protein. The linker peptide comprises a flexible peptide and a rigid peptide. The flexible peptide consists of one or more flexible units. The rigid peptide consists of one or more rigid units. The flexible unit comprises two or more amino acid residues selected from Gly, Ser, Ala, and Thr. The rigid unit comprises a human chorionic gonadotropin ?-subunit carboxy-terminal peptide (CTP) bearing a plurality of glycosylation sites. The linker peptide can more effectively eliminate mutual steric hindrance of two fusion molecules, decreasing a reduction/loss of polymerization or activity resulting from improper folding of an active protein or a conformational change. On the other hand, the negatively charged, highly sialylated CTP can resist renal clearance, further prolonging a half-life of a fused molecule and enhancing bioavailability of a fused protein.

Abstract: Provided is a tetravalent, homodimer-type bispecific antibody molecule that targets both immune effector cell antigen CD3 and tumor-related antigen CD19. The bispecific antibody molecule comprises first and second single-chain Fv and Fc fragments in sequence from the N-terminus to the C-terminus, wherein the first single-chain Fv can specifically bind to CD19, the second single-chain Fv can specifically bind to CD3, the first and second single-chains Fv are connected by means of a linker peptide, the second single-chain Fv and Fc fragments are directly connected to each other or connected by means of a linker peptide; and the Fc fragment does not have effector functions such as CDC, ADCC, and ADCP.

Abstract: Disclosed is a bispecific antibody that specifically binds to surface antigens CD3 of immune cells and CD20 antigens on the surfaces of tumor cells, and that can bind to human CD3 with high affinity, inducing T cell proliferation, and mediating tumor cell killing. The bispecific antibody in an in vitro test was able to mediate the specific killing of target cells by T cells. The construction method thereof is simple, avoiding the possibility of mismatch between two sets of light chains and heavy chains of heterobispecific antibodies, thereby reducing the difficulty of antibody purification. The affinity of the obtained antibody is high, the side effects caused by cytokines are small, and safety is high.

Abstract: Provided is a tetravalent homodimeric bispecific antibody molecule simultaneously targeting an immune effector cell antigen CD3 and a tumor-associated antigen, wherein the bispecific antibody molecule contains, in order from N-terminus to C-terminus, a first single chain Fv, a second single chain Fv and a Fc fragment; wherein the first single chain Fv can specifically bind to the tumor-associated antigen, the second single chain Fv can specifically bind to CD3, and the first and the second single chain Fvs are connected by a linker peptide, while the second single chain Fv and the Fc fragment are directly connected or connected by a linker peptide; and the Fc fragment does not have effector functions such as CDC, ADCC and ADCP.

Abstract: This disclosure provides an antibody specifically binding to PD-1 with high affinity. Also provided are a nucleic acid molecule for coding the antibody, an expression vector and a host cell for expressing the antibody, and a production method for the antibody. In addition, also provided are an immunoconjugate and a pharmaceutical composition comprising the antibody and use of the antibody in preparation of drugs for treating cancers, infectious diseases, and inflammatory diseases.

Abstract: A linker peptide for constructing a fusion protein. The linker peptide comprises a flexible peptide and a rigid peptide. The flexible peptide consists of one or more flexible units. The rigid peptide consists of one or more rigid units. The flexible unit comprises two or more amino acid residues selected from Gly, Ser, Ala, and Thr. The rigid unit comprises a human chorionic gonadotropin ?-subunit carboxy-terminal peptide (CTP) bearing a plurality of glycosylation sites. The linker peptide can more effectively eliminate mutual steric hindrance of two fusion molecules, decreasing a reduction/loss of polymerization or activity resulting from improper folding of an active protein or a conformational change. On the other hand, the negatively charged, highly sialylated CTP can resist renal clearance, further prolonging a half-life of a fused molecule and enhancing bioavailability of a fused protein.

Abstract: Provided by the present invention are an antibody against human TIM-3 or an antigen-binding fragment thereof, and further provided are a nucleic acid molecule encoding the antibody, an expression vector for expressing the antibody and a host cell, and a method for producing the antibody. Further provided by the present invention are a pharmaceutical composition comprising the antibody or an antigen-binding fragment of the antibody, and an application of the pharmaceutical composition in the preparation of a medicine, the medicine is used for preventing and/or treating various diseases (including tumors, infectious diseases and autoimmune diseases).

Abstract: An antibody specifically binding to PD-1 with high affinity. Also provided are a nucleic acid molecule for coding the antibody, an expression vector and a host cell for expressing the antibody, and a production method for the antibody In addition, also provided are an immunoconjugate and a pharmaceutical composition comprising the antibody, and use of the antibody in preparation of drugs for treating cancers, infectious diseases, inflammatory diseases.

Abstract: A linker peptide for constructing a fusion protein. The linker peptide comprises a flexible peptide and a rigid peptide. The flexible peptide consists of one or more flexible units. The rigid peptide consists of one or more rigid units. The flexible unit comprises two or more amino acid residues selected from Gly, Ser, Ala, and Thr. The rigid unit comprises a human chorionic gonadotropin ?-subunit carboxy-terminal peptide (CTP) bearing a plurality of glycosylation sites. The linker peptide can more effectively eliminate mutual steric hindrance of two fusion molecules, decreasing a reduction/loss of polymerization or activity resulting from improper folding of an active protein or a conformational change. On the other hand, the negatively charged, highly sialylated CTP can resist renal clearance, further prolonging a half-life of a fused molecule and enhancing bioavailability of a fused protein.