Igh variable region-restricted T cell interactions. Genetic restriction of an antigen-specific suppressor inducer factor is imparted by an I-J+ antigen-nonspecific molecule.
Immunized Ly-1 T cells secrete an antigen-specific molecule that will induce Ly-2+ T cells to express suppressive activity. In two separate systems, factors that suppress the primary anti-sheep erythrocyte (SE) plaque-forming cell response of spleen cells in vitro (Ly-1 TsiF) or the contact sensitivity of azobenzenearsonate (ABA)-TsF1 consist of two macromolecules, one which binds antigen and is IJ-, the other which is I-J+ and does not bind antigen. Both of these chains are required for the factor's biological activity. These factors show a genetic restriction in their ability to induce suppression that is linked to the variable region of the Ig heavy chain gene complex (Igh-V). The I-J+ chain from the ABA-specific TsF1 could replace the I-J+ chain needed by the SE-specific Ly-1 TsiF for biological activity. Mixtures of ABA-binding chain with I-J+ material obtained from the SE-specific Ly-1 TsiF had no effect on the primary anti-SE response in vitro. In mixtures of SE antigen-binding chain from Ly-1 TsiF and I-J+ material from the ABA-specific TsF1, it is the I-J+ molecule that determined the factor's Igh-V restriction. Thus, the antigen-combining site of the factor determined the antigen specificity of this factor but is irrelevant to its Igh-V-linked genetic restrictions. The implications of these results for the idiotype network hypothesis are discussed.
D000818:Animals; D000911:Antibodies, Monoclonal; D000950:Antigens, Ly / Q000276:immunology; D000939:Epitopes; D007143:Immunoglobulin Heavy Chains / Q000235:genetics*; D007135:Immunoglobulin Variable Region / Q000235:genetics*; D008222:Lymphokines / Q000276:immunology*; D051379:Mice; D008815:Mice, Inbred Strains; D008957:Models, Genetic; D013491:Suppressor Factors, Immunologic; D013601:T-Lymphocytes / Q000276:immunology*
D000911:Antibodies, Monoclonal; D000950:Antigens, Ly; D000939:Epitopes; D007143:Immunoglobulin Heavy Chains; D007135:Immunoglobulin Variable Region; D008222:Lymphokines; D013491:Suppressor Factors, Immunologic