title: In vitro T cell-mediated killing of Pseudomonas aeruginosa. IV. Nonresponsiveness in polysaccharide-immunized BALB/c mice is attributable to vinblastine-sensitive suppressor T cells.
abstract: We reported previously that BALB/c mice immunized with a polysaccharide (PS) antigen isolated from immunotype 1 Pseudomonas aeruginosa and vinblastine sulfate develop T cell-mediated protective immunity, despite their failure to produce specific antibody. In vitro, Lyt-1-,2+, I-J+ T cells from vinblastine- and PS-immunized mice kill P. aeruginosa by secretion of a bactericidal lymphokine. BALB/c mice immunized with PS alone generate neither protective antibodies nor a protective T cell response. The current studies indicate that T cells from mice immunized with PS alone significantly suppress the bactericidal activity of T cells from mice immunized with vinblastine and PS. The suppressor T cells are of the same Lyt-1-,2+, I-J+ phenotype as the bactericidal T cells. Suppression is mediated by a soluble product of these suppressor T cells which both inhibits T cell proliferation and interferes with the production or release of the bactericidal lymphokine. Cyclophosphamide, used in other systems to remove suppressor T cells, fails to enhance bacterial killing and does not inhibit suppressor cell activity. These studies indicate that immunization with PS elicits responses in two functionally distinct subgroups of Lyt-1-,2+, I-J+ T cells, and that these cells are distinguishable by their sensitivity to vinblastine sulfate.
mesh_terms: D000818:Animals; D000945:Antigens, Differentiation, T-Lymphocyte; D000950:Antigens, Ly / Q000032:analysis; D000954:Antigens, Surface / Q000032:analysis; D001770:Blood Bactericidal Activity / Q000187:drug effects; D003520:Cyclophosphamide / Q000494:pharmacology; D007108:Immune Tolerance; D007111:Immunity, Cellular / Q000187:drug effects; D051379:Mice; D008807:Mice, Inbred BALB C; D011135:Polysaccharides, Bacterial / Q000276:immunology*; D011550:Pseudomonas aeruginosa / Q000276:immunology*; D013491:Suppressor Factors, Immunologic / Q000276:immunology; D050378:T-Lymphocytes, Regulatory / Q000145:classification / Q000187:drug effects / Q000276:immunology*; D014747:Vinblastine / Q000494:pharmacology
chemical_list: D000945:Antigens, Differentiation, T-Lymphocyte; D000950:Antigens, Ly; D000954:Antigens, Surface; D011135:Polysaccharides, Bacterial; D013491:Suppressor Factors, Immunologic; D014747:Vinblastine; D003520:Cyclophosphamide