title: Antigen specific T cell factors.
abstract: Antigen specific helper and suppressor factors have a similar structure, with two major sections, a 'variable region', determining antigen specificity which is likely to be controlled by Immunoglobulin VH genes, with which it shares idiotype and framework determinants. Specific factors also have a 'constant region' which does not vary between strains and minimally between species or with the antigenic specificity of the factors, which are defined by rabbit anti-helper or anti-suppressor antisera. This region determines the biological function of the molecule. Anti-Ia antisera react with factors, but the nature and function of Ia molecules on T cell factors is still unclear. The model of specific factor structure, with C and V regions resembles that of immunoglobulin, and it is thus possible that the C region of factors, like the V region is Ig linked. Because there are multiple T cells, helping and suppressing antibody responses specifically, it seems improbable that all of these cells could interact directly with rare antigen-specific B cells. Thus we propose that macrophage presenting cells are the key to the integration of signals for immune induction and regulation for T and B cells. Since Ir genes have been identified in the macrophage presenting cells interacting with both T and B cells, this suggests that macrophage Ia antigens are of importance in the integration of triggering signals for the lymphoid pool.
mesh_terms: D000818:Animals; D000917:Antibody Formation; D000954:Antigens, Surface; D001402:B-Lymphocytes / Q000276:immunology; D000939:Epitopes; D005802:Genes, MHC Class II; D006801:Humans; D007126:Immunoglobulin Allotypes; D007165:Immunosuppression Therapy; D008211:Lymphocyte Cooperation; D008264:Macrophages / Q000276:immunology; D051379:Mice; D008970:Molecular Weight; D051381:Rats; D011947:Receptors, Antigen, B-Cell / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D000954:Antigens, Surface; D000939:Epitopes; D007126:Immunoglobulin Allotypes; D011947:Receptors, Antigen, B-Cell