title: Serologic heterogeneity in I-J determinants associated with functionally distinct T cell regulatory factors.
abstract: Information transfer among regulatory T cell subsets is mediated by biologically active T cell factors. Many of these factors are comprised of two molecules: one that binds antigen, and another that is I-J+ and determines the self recognition capability of the factor (I-J molecule). In the in vitro response to sheep red blood cells, we used three functionally distinct I-J+ factors to study the relationship between polymorphic I-J determinants and the biological activity of these factors. Our study shows that several monoclonal I-J antibodies react with I-J molecules associated with T suppressor-inducer factor (TsiF) and T suppressor-effector factor (TseF), but not with T contrasuppressor inducer factor (TcsiF). In contrast, a different set of monoclonal I-J reagents reacts with TcsiF but not TsiF or TseF. Finally, some monoclonal I-J antibodies distinguish between I-J molecules associated with TsiF and TseF. Thus anti-I-J reagents differentially react with I-J determinants on regulatory factors, and this differential pattern of reactivity correlates with the functional activity of the factors. The possible relationship between I-J heterogeneity and the biological function of I-J molecules in regulation is discussed.
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal; D000917:Antibody Formation; D000939:Epitopes; D000949:Histocompatibility Antigens Class II / Q000276:immunology*; D008222:Lymphokines / Q000276:immunology*; D051379:Mice; D008815:Mice, Inbred Strains; D013491:Suppressor Factors, Immunologic / Q000145:classification / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*; D050378:T-Lymphocytes, Regulatory / Q000276:immunology
chemical_list: D000911:Antibodies, Monoclonal; D000939:Epitopes; D000949:Histocompatibility Antigens Class II; D008222:Lymphokines; D013491:Suppressor Factors, Immunologic