title: Nature of the antigenic complex recognized by T lymphocytes. IV. Inhibition of antigen-specific T cell proliferation by antibodies to stimulator macrophage Ia antigens.
abstract: We have previously demonstrated that nonimmune guinea pig T lymphocytes could be specifically sensitized with TNP-modified allogeneic macrophages after eliminating the alloreactive T cells with bromodeoxyuridine (BUdR) and light treatment. This procedure allowed the unique opportunity to use anti-Ia sera directed against the Ia antigens of only the stimulator macrophages or responder T cells to determine against which cell type anti-Ia would block TNP-specific stimulation. It was found that the TNP-specific DNA synthetic response of BUdR and light-treated T cells stimulated with TNP-modified allogeneic macrophages was totally eliminated by anti-Ia sera directed solely against the allogeneic stimulator macrophage. In contrast, anti-Ia sera directed only against the responder T cells had no effect on their response to TNP-modified allogeneic macrophages. These findings indicate that macrophage Ia antigens are required for efficient T cell-macrophage interactions and raise the possibility that T cell Ia antigens may not be required for collaboration with macrophages. This latter possibility was substantiated by experiments in which we show that treating T cells with anti-Ia sera and complement to remove the Ia-positive cells either before or after priming, or both, had no effect on their ability to be primed and restimulated with TNP-modified macrophages.
mesh_terms: D000818:Animals; D000906:Antibodies; D000936:Antigen-Antibody Complex; D001973:Bromodeoxyuridine / Q000378:metabolism; D000939:Epitopes; D006168:Guinea Pigs; D006649:Histocompatibility Antigens; D007106:Immune Sera / Q000494:pharmacology; D008027:Light; D008213:Lymphocyte Activation; D008264:Macrophages / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*; D014301:Trinitrobenzenes / Q000276:immunology
chemical_list: D000906:Antibodies; D000936:Antigen-Antibody Complex; D000939:Epitopes; D006649:Histocompatibility Antigens; D007106:Immune Sera; D014301:Trinitrobenzenes; D001973:Bromodeoxyuridine