title: T cell regulation of B cell activation. T cells independently regulate the responses mediated by distinct B cell subpopulations.
abstract: The present studies have been carried out to characterize the regulatory influences acting upon defined pathways of T cell-dependent B cell activation. In these studies, it was demonstrated that high concentrations of free carrier strongly inhibited the MHC-restricted in vitro T cell-dependent antibody responses of primed Lyb-5- B cells to the corresponding carrier-hapten conjugate. In contrast, these same concentrations of free carrier failed to inhibit the T cell dependent responses of Lyb-5+ B cells to the same antigen. The inhibition of Lyb-5- B cell responses by free carrier was shown to result from active suppression mediated by carrier-specific primed Lyt-1+2- T cells and to require the additional participation of unprimed Lyt-1-2+ T cells. The activation of this suppression was antigen-specific, but suppression once activated was antigen nonspecific in its effect. These findings thus demonstrate that distinct pathways of B cell activation can be independently regulated by T suppressor network influences, and that these pathways therefore constitute potentially independent components of the immune response to a given antigenic stimulus.
mesh_terms: D000818:Animals; D000950:Antigens, Ly; D001402:B-Lymphocytes / Q000145:classification / Q000276:immunology*; D002352:Carrier Proteins / Q000276:immunology; D004306:Dose-Response Relationship, Immunologic; D000939:Epitopes; D006433:Hemocyanins / Q000276:immunology; D008213:Lymphocyte Activation; D008211:Lymphocyte Cooperation; D008222:Lymphokines / Q000494:pharmacology; D051379:Mice; D008807:Mice, Inbred BALB C; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D008974:Mollusca; D011200:Poultry; D013491:Suppressor Factors, Immunologic; D013601:T-Lymphocytes / Q000145:classification / Q000276:immunology*; D014301:Trinitrobenzenes / Q000276:immunology
chemical_list: D000950:Antigens, Ly; D002352:Carrier Proteins; D000939:Epitopes; D008222:Lymphokines; D013491:Suppressor Factors, Immunologic; D014301:Trinitrobenzenes; D006433:Hemocyanins