title: Nonspecific T suppressor factor (nsTsF) cascade in contact sensitivity: nsTsF-1 causes an Ly-1+2- I-A+ immune T cell to produce a second, genetically restricted, nsTsF-2.
abstract: We studied the mode of action of the nonspecific T suppressor factor (nsTsF-1) made in the picryl (TNP) system when T acceptor cells armed with antigen-specific TsF are triggered by antigen in the context of I-J. This suppressor factor does not inhibit the passive transfer of contact sensitivity directly, as shown by its failure to inhibit passive transfer by immune cells deprived of I-A+ cells. Its immediate target is an immune, antigen-specific, Ly-1+2-, I-A+ T cell. This cell, which may be regarded as a T suppressor effector cell (Ts-eff-2), produces nsTsF-2 when exposed sequentially to nsTsF-1 and antigen. This nsTsF subsequently inhibits the passive transfer of contact sensitivity. The action of nsTsF-2 is MHC genetically restricted. As the nsTsF-2 bears I-A determinant(s), this raises the possibility that it may act by combining with the recognition site for I-A on the T cell that mediates contact sensitivity.
mesh_terms: D000818:Animals; D000950:Antigens, Ly / Q000276:immunology; D003877:Dermatitis, Contact / Q000276:immunology*; D000939:Epitopes / Q000276:immunology; D006183:H-2 Antigens / Q000235:genetics; D000949:Histocompatibility Antigens Class II / Q000276:immunology; D007108:Immune Tolerance; D007116:Immunization, Passive; D051379:Mice; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D010641:Phenotype; D013491:Suppressor Factors, Immunologic / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology*; D050378:T-Lymphocytes, Regulatory / Q000145:classification* / Q000276:immunology / Q000378:metabolism
chemical_list: D000950:Antigens, Ly; D000939:Epitopes; D006183:H-2 Antigens; D000949:Histocompatibility Antigens Class II; D013491:Suppressor Factors, Immunologic