Abstract: A bispecific antibody binding to BCMA and CD3, and a preparation method therefor and the use thereof. A bispecific antibody, which can bind to BCMA and CD3 simultaneously, has specific targeting effects and can efficiently stimulate directed immune responses. The bispecific antibody retains the biological functions of an anti-CD3 antibody and an anti-BCMA antibody, enables the bispecific antibody molecule to achieve excellent biological functions of simultaneously binding to BCMA and CD3 in a targeted manner, forms a bridge between tumor cells and immune effector cells, effectively activates the immune effector cells and the directed immune responses, significantly enhances the effects of immune cells in killing tumor cells, has a high targeted cell killing efficiency, reduces the ADCC effect to the largest extent, has high safety, and has good application prospects in tumor immunotherapy.

Abstract: A bispecific antibody, a preparation method therefor and an application thereof. The bispecific antibody includes a monoclonal antibody unit and a single-chain antibody unit. The single-chain antibody unit includes two complete light chain-heavy chain pairs, and is specifically bound to a surface antigen of a tumor cell. The single-chain antibody unit includes two single-chain antibodies. The single-chain antibody includes a heavy chain variable region and a light chain variable region, and is specifically bound to a surface antigen of an immunocyte. The bispecific antibody can be simultaneously bound to the immunocyte and the tumor cell, can mediate a directed immune response, and can effectively kill the tumor cell.