A HER2 bispecific antibody can be efficiently expressed in with potent cytotoxicity.

Bispecific antibodies have been actively studied for cancer therapy due to their potent cytotoxicity against tumor cells. A number of bispecific antibody formats have exhibited strong tumor cytotoxicity and . However， effective production of bispecific antibodies remains challenging for the majority of bispecific antibody formats. In the present study， a bispecific antibody was designed that links a conventional antigen-binding fragment (Fab) against cluster of differentiation 3 antigen (CD3) to a camel single domain antibody (VHH) against human epidermal growth factor receptor 2 (HER2). This bispecific antibody may be secreted and purified efficiently from culture medium. The purified bispecific antibody is able to trigger T cell-mediated HER2-specific cytotoxicity and . The data gathered in the present study suggest that this bispecific format may be applied to other tumor antigens to produce bispecific antibodies more efficiently.