Back on the scene: Advances and challenges in CD3-related drugs in tumor therapy

CD3 molecules are mainly distributed on the membrane of mature T cells. They are involved in T cell antigen recognition, signal transduction, and regulation of T cell development. CD3-related monoclonal antibodies (mAbs) are mainly used in the treatment of autoimmune diseases. Nearly half of all bispecific antibodies developed are used in tumor therapy, one of which is CD3 antigen. In this review, we discuss the importance of biological function and the crucial role of CD3 in tumor therapy. We highlight the research status of antibodies and small molecules targeting CD3 to provide guidance for future drug research.