title: Differential antigen presentation in tumor immunity.
abstract: The tumor S1509a elicits a cell-mediated immune response in immune A/J mice but leads to the generation of suppressor T cells (Ts) in nonimmune mice. Previous studies have shown that I-A+ antigen-presenting cells (APC) present S1509a tumor antigen and thereby activate immune T cells. Recent studies with polyoma-induced tumors reveal similar findings. Administration of anti-I-A antibodies not only prevents effective T cell activation by I-A+ APC bearing S1509a tumor antigen but also induces Ts after a tumor challenge. Ts, which inhibit S1509a tumor immunity, may be activated by tumor antigen presented on I-J+ APC. Examination of the immunologic effects of cyclophosphamide and UV radiation supports this hypothesis.
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal; D000951:Antigens, Neoplasm / Q000276:immunology*; D003520:Cyclophosphamide / Q000494:pharmacology; D005354:Fibrosarcoma / Q000276:immunology; D006183:H-2 Antigens / Q000276:immunology; D000949:Histocompatibility Antigens Class II / Q000276:immunology; D006968:Hypersensitivity, Delayed; D007106:Immune Sera; D007111:Immunity, Cellular; D051379:Mice; D008805:Mice, Inbred A; D008954:Models, Biological; D009374:Neoplasms, Experimental / Q000276:immunology*; D009381:Neoplasms, Radiation-Induced / Q000276:immunology; D011120:Polyomavirus; D012878:Skin Neoplasms / Q000209:etiology; D013601:T-Lymphocytes / Q000276:immunology; D050378:T-Lymphocytes, Regulatory / Q000187:drug effects / Q000276:immunology* / Q000528:radiation effects; D014412:Tumor Virus Infections / Q000276:immunology; D014466:Ultraviolet Rays
chemical_list: D000911:Antibodies, Monoclonal; D000951:Antigens, Neoplasm; D006183:H-2 Antigens; D000949:Histocompatibility Antigens Class II; D007106:Immune Sera; D003520:Cyclophosphamide