title: Characterization and activity of contrasuppressor T cells induced by type III pneumococcal polysaccharide.
abstract: Optimally immunogenic amounts of type III pneumococcal polysaccharide (S3) activate a population of contrasuppressor T cells (Tcs), which have been shown to play an important role in the induction of anti-S3 antibody responses. These Tcs belong to a unique T cell subset that has the surface phenotype Lyt 1+2- L3T4- I-J+ I-A+. These Tcs are also cyclophosphamide (Cy)-sensitive and sensitive to antilymphocyte serum (ALS) and mitomycin C. Tcs have antigen-binding receptors, indicating that any interactions of Tcs with B cells or T suppressor cells (Ts) (both of which also have antigen-binding receptors) must be via an antigen bridge rather than an idiotype-anti-idiotype interaction. Tcs are also Igh restricted in their action. Contrasuppression is manifest only when the Tcs are Igh compatible with both the Ts and the responding B cells. Tcs apparently mediate their effects by releasing a soluble factor, since a soluble factor extracted from Tcs is able to abrogate the effects of S3-specific Ts.
mesh_terms: D000818:Animals; D000945:Antigens, Differentiation, T-Lymphocyte; D000950:Antigens, Ly / Q000032:analysis; D000954:Antigens, Surface / Q000032:analysis; D003520:Cyclophosphamide / Q000494:pharmacology; D005260:Female; D000949:Histocompatibility Antigens Class II / Q000032:analysis; D007143:Immunoglobulin Heavy Chains / Q000276:immunology; D008222:Lymphokines / Q000276:immunology; D051379:Mice; D016685:Mitomycin; D008937:Mitomycins / Q000494:pharmacology; D011135:Polysaccharides, Bacterial / Q000276:immunology*; D011948:Receptors, Antigen, T-Cell / Q000276:immunology; D013296:Streptococcus pneumoniae / Q000276:immunology*; D013601:T-Lymphocytes / Q000145:classification / Q000187:drug effects / Q000276:immunology*; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*
chemical_list: D000945:Antigens, Differentiation, T-Lymphocyte; D000950:Antigens, Ly; D000954:Antigens, Surface; D000949:Histocompatibility Antigens Class II; D007143:Immunoglobulin Heavy Chains; D008222:Lymphokines; D008937:Mitomycins; D011135:Polysaccharides, Bacterial; D011948:Receptors, Antigen, T-Cell; D016685:Mitomycin; D003520:Cyclophosphamide