| abstract |
Provided is a binding protein, which comprises a protein functional region A and a protein functional region B, both of which target different antigens or different epitopes of antigens. The protein functional region A is Fab; the protein functional region B is VH; and the binding protein also comprises an Fc homodimer. There are two of both the protein functional region A and the protein functional region B. The binding protein has a left-right symmetrical structure. The binding protein consists of the protein functional region A, the protein functional region B and Fc in sequence from the N-terminus to the C-terminus, wherein the protein functional region A and the protein functional region B are connected by means of L1, and the protein functional region B is connected to the Fc by means of L2. The binding protein has a relatively small molecular mass, few polypeptide chains and a simpler structure. The protein has a versatile structure and may be applied to a variety of different target combinations. Compared with bispecific binding proteins in other structures, the binding protein has stronger ability to activate effector cells. |