title: Antigen-specific suppression in genetic responder mice to L-glutamic acid60-L-alanine30-L-tyrosine10 (GAT). Characterization of conventional and hybridoma-derived factors produced by suppressor T cells from mice injected as neonates with syngeneic GAT macrophages.
abstract: Spleen cells from C57BL/10 mice injected with syngeneic B10 L-glutamic acid60-L-alanine30-L-tyrosine10 (GAT)-pulsed macrophages (GAT-M phi) within 18 h of birth were unable to respond to soluble GAT, GAT-methylated bovine serum albumin, or B10 GAT-M phi as adults. Spleen cells from these neonatally treated mice responded at control levels to GAT presented in allogeneic M phi and to sheep erythrocytes. Partially purified T cells from these neonatally treated mice suppressed responses by syngeneic virgin, but not primed, spleen cells in an antigen-specific manner and acted during the early phases of the response. These responder GAT-specific suppressor T cells (GAT-TSR) were sensitive to anti-Thy-1 + C and 500-rad irradiation and have the phenotype Ly-1-2+, I-J+; GAT-TSR cells can only suppress responses by spleen cells syngeneic with the GAT-TSR cells at the I-J subregion of H-2. Restimulation of these Ts cells with syngeneic GAT-M phi induces an antigen-specific suppressor factor within the supernatant fluid. The factor, GAT-TsFR, is a glycoprotein with a molecular weight between 48,000 and 63,000, as determined by gel filtration chromatography using isotonic buffers; it bears serologically detectable determinants encoded by the I-J subregion of the H-2 complex, has an antigen-binding site for GAT and L-glutamic acid50-L-tyrosine50, and shares idiotypic determinants with anti-GAT antibodies. The presence of GAT-TsFR in the first 36 h of in vitro culture is required for significant suppression. Furthermore, only responses by spleen cell syngeneic with the cells producing GAT-TsFR at the I-J subregion are suppressed. The fusion of GAT-TsFR-producing cells with BW5147 resulted in generation of two hybridomas with properties and characteristics identical to those of the conventional GAT-TsFR with one exception: conventional and hybridoma 372.D6.5 GAT-TsFR only suppress responses by spleen cells of the I-Jb haplotype, whereas suppression mediated by the second hybridoma GAT-TsFR (372.B3.5) is genetically unrestricted. These hybridoma GAT-TsFR are compared with nonresponder GAT-Ts factor (GAT-TsF) and these responder and nonresponder GAT-TsF are considered in the context of suppressor pathways.
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D000921:Antibody-Producing Cells / Q000276:immunology; D000939:Epitopes / Q000235:genetics*; D005802:Genes, MHC Class II; D006462:Hemolytic Plaque Technique; D006825:Hybridomas / Q000276:immunology*; D008222:Lymphokines / Q000032:analysis / Q000096:biosynthesis / Q000494:pharmacology; D008264:Macrophages / Q000276:immunology / Q000637:transplantation; D051379:Mice; D008805:Mice, Inbred A; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D010455:Peptides / Q000235:genetics / Q000276:immunology*; D011108:Polymers; D013491:Suppressor Factors, Immunologic; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*
chemical_list: D000939:Epitopes; D008222:Lymphokines; D010455:Peptides; D011108:Polymers; D013491:Suppressor Factors, Immunologic; C020749:GAT