Abstract: The present invention relates to a specific binding protein targeting PD-L1 and CD73, wherein the specific binding protein is capable of specifically binding to PD-L1 and/or a fragment thereof, and CD73 and/or a fragment thereof. The present invention further relates to use of the specific binding protein in the treatment, prevention and/or diagnosis of diseases such as immune diseases, acute and chronic inflammatory diseases, and tumor diseases.

Abstract: Disclosed is a binding protein having at least two protein functional regions, the binding protein comprising a protein functional region A and a protein functional region B; the protein functional region A and the protein functional region B target different antigens or epitopes, the protein functional region A is a Fab or a scFv structure, the protein functional region B is a VH structure, and there are one or more of each of the protein functional region A and the protein functional region B. A multi-specific binding protein has a smaller molecular weight, fewer polypeptide chains, and a simpler structure. By means of different structure types, relative positions, binding valence and other parameters, the functional activities for different targets can be adjusted, and then different combinations of activities can be designed so as to meet the needs of different dose combinations of clinical combinations.

Abstract: An OX40-targeted antibody or an antigen binding fragment thereof. The OX40-targeted antibody comprises a VH. The VH comprises the following CDRs or mutants thereof: a VH CDR1 as shown in an amino acid sequence of SEQ ID NO: 10, a VH CDR2 as shown in an amino acid sequence of SEQ ID NO: 44, and/or a VH CDR3 as shown in an amino acid sequence of SEQ ID NO: 86, SEQ ID NO: 84, or SEQ ID NO: 89. Also disclosed is a preparation method, an application, and a double-antibody comprising same. The antibody or the antigen binding fragment thereof can specifically bind to OX40, promote larger activation of NF-Kb, activate OX40 pathways in vitro, and induce activation of T cell function. The double-antibody can identify tumor target TAA, can bind to OX40 on the T cell, and can recruit and activate T cells near tumor cells to kill tumor cells.