title: A novel cytotoxic T-cell clone that exhibits differential modes of recognition in the proliferative and cytolytic phase.
abstract: A T-cell clone (1G8-H7) cytotoxic to P815Y mastocytoma (H-2d) has been established from spleen cells of a C3H/He mouse (H-2k) primed with P815Y cells by means of in vitro stimulation with irradiated C3H.H-2o(H-2KdDk) spleen cells. The clone 1G8-H7 was an interleukin 2 (IL-2)-dependent and H-2Kd antigen-dependent CTL clone and it killed P815Y cells but not Concanavalin A-induced spleen blast cells bearing H-2Kd antigen. The involvement of H-2Kd antigen in the cytolytic recognition mechanism was shown by the inhibition of lysis by anti-H-2Kd monoclonal antibody and also by the cold inhibition experiment that employed H-2Kd-bearing spleen cells. Comparison of cytotoxic activities between 1G8-H7 and Kd-specific CTL clones showed that the killing of P815Y cells by clone 1G8-H7 was not explained by the susceptibility to cell-mediated cytolysis of P815Y cells. These results suggest that H-2Kd antigen on the stimulating cell is sufficient to deliver a proliferation signal in the proliferative phase of this clone, but in the cytolytic phase an additional interaction with surface structure on the target cell other than that with H-2Kd antigen is required for the induction of cytolysis. Possible elucidations for the differential modes of recognition are discussed.
mesh_terms: D000818:Animals; D000950:Antigens, Ly / Q000032:analysis; D002999:Clone Cells; D003080:Cold Temperature; D003602:Cytotoxicity, Immunologic; D006183:H-2 Antigens / Q000276:immunology; D008213:Lymphocyte Activation; D051379:Mice; D008815:Mice, Inbred Strains; D011948:Receptors, Antigen, T-Cell / Q000502:physiology; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*
chemical_list: D000950:Antigens, Ly; D006183:H-2 Antigens; D011948:Receptors, Antigen, T-Cell