[Human cytotoxic T cell clones that recognize HLA-DQw3 antigens].

Human cytotoxic T cell (CTL) clones generated against a DQw3-positive EBV-transformed B cell line were analyzed in terms of immunological characteristics. The cytolytic activities of clones 1-18 and 3-34 were inhibited by anti-DQw3 monoclonal antibodies (HU-18 and HU-23), but they were not affected by anti-DR (HU-4 and HU-20) and anti-HLA-A, B, C (W6/32) monoclonal antibodies. In contrast to that the clone 1-18 cytolyzed all the human B cell lines typed as DQw3, the clone 3-34 reacted only with DR4/Dw4 and DR5-positive cells that were positive for HU-23 and typed as TA10. In addition, the clone 3-34 were cross-reactive to DQw2-typed cells. These results show that there are two epitopes that CTL recognize on the same DQw3 molecules; one is the public epitope among DQw3 antigens, and the other is the private epitope that HU-23 recognizes. This is the further evidence for CTL recognition of HLA-DQ antigens.