Abstract: Related are a novel antibody specifically binding with B7-H3, an antigen-binding fragment of the antibody, and a composition comprising the antibody or the antigen-binding fragment thereof. Related are nucleic acids encoding the antibody or the antigen-binding fragment thereof, a host cell comprising the nucleic acids, and relevant uses. In addition, related are therapeutic and diagnostic uses of the antibody and the antigen-binding fragment thereof.

Abstract: The present invention provides a novel artificial triple-chain antibody comprising three polypeptide chains, wherein a first polypeptide chain comprises a first heavy-chain variable domain, a second polypeptide chain comprises a first light-chain variable domain that is paired with the first heavy-chain variable domain to form a first antigen-binding site; and a third polypeptide chain comprises a second single-domain antigen-binding site and a third single-domain antigen-binding site. The present invention also provides a polynucleotide encoding the triple-chain antibody, a vector comprising the polynucleotide, a host cell comprising the polynucleotide or vector, an immunoconjugate comprising the triple-chain antibody and a pharmaceutical composition comprising the triple-chain antibody or the immunoconjugate thereof, and use of the triple-chain antibody in immunotherapy, prevention and/or diagnosis of diseases.

Abstract: The present invention provides a novel, artificially designed antibody molecule comprising: a polypeptide chain of formula (I): VH-CH1-Fc-X-VHH; and a polypeptide chain of formula (II): VL-CL; wherein: the VH represents a heavy chain variable region; the CH represents a heavy chain constant region; the Fc comprises CH2, CH3, and optionally CH4; the CH1, the CH2, the CH3 and the CH4 represent domains 1, 2, 3 and 4, respectively, of the heavy chain constant region; the X may be absent, or represents a linker such as a flexible linker when present; the VHH represents a single-domain antigen-binding site such as a single-domain antibody; the VL represents a light chain variable region; the CL represents a light chain constant region; optionally, a hinge region is present between the CH1 and the Fc.