Human allospecific cytolytic T lymphocyte lysis of a murine cell transfected with HLA-A2

A variety of molecules are involved in the interaction of human allospecific cytolytic T lymphocytes (CTL) with target cells. Monoclonal antibodies specific for these molecules inhibit CTL-target conjugate formation and/or lysis. To further study recognition and lysis of targets by human CTL, we used a murine mastocytoma cell line transfected with the histocompatibility leukocyte antigen (HLA)-A2 gene (P815-A2⁺) as a target for human HLA-A2-specific CTL. We find that only a subset of human HLA-A2-specific CTL can lyse murine P815-A2⁺ cells, suggesting that the murine cells may lack one or more accessory molecules needed for CTL recognition and lysis.