title: Antigen-specific and nonspecific mediators of T cell/B cell cooperation. III. Characterization of the nonspecific mediator(s) from different sources.
abstract: T cell-containing lymphoid populations produce a nonantigen-specific mediator(s) (NSM) which can replace T cell helper function in vitro in the response of B cells to sheep red blood cells (SRBC), but not to the hapten-protein conjugate, trinitrophenyl-keyhole limpet hemocyanin, (TNP-KLH). NSM produced under three conditions: 1) stimulation of KLH-primed cells with KLH; 2) allogeneic stimulation of normal spleen cells; and 3) stimulation of normal spleen cells with Con A (but not PHA) are indistinguishable on the basis of their biologic activity and m.w., estimated as 30 to 40,000 daltons by G-200 chromatography. Production of NSM is dependent on the presence of T cells. The action of NSM on B cells responding to SRBC in the presence of 2-mercaptoethanol is unaffected by severe macrophage depletion. Extensive absorption of NSM with SRBC failed to remove its activity, confirming its nonantigen-specific nature.
mesh_terms: D000818:Animals; D000917:Antibody Formation; D001402:B-Lymphocytes / Q000276:immunology*; D002448:Cell Adhesion; D002850:Chromatography, Gel; D000939:Epitopes; D006433:Hemocyanins / Q000276:immunology; D066298:In Vitro Techniques; D051379:Mice; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D009578:Nitrobenzenes / Q000276:immunology; D013154:Spleen / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D000939:Epitopes; D009578:Nitrobenzenes; D006433:Hemocyanins