title: Clonal analysis of F1 hybrid helper T cells. I-A subregion-encoded hybrid determinants restrict the activity of keyhole limpet hemocyanin-specific helper T cells.
abstract: Clonal expansion of isolated precursors to helper T cells was induced in limiting dilution cultures of keyhole limpet hemocyanin (KLH)-primed F1 hybrid lymph node cells. Progeny of each isolated precursor was tested for helper activity by transfer to independent cultures with hapten-primed B cells of either parental or F1 hybrid origin. The major histocompatibility complex (MHC) restriction specificity of each F1 hybrid helper T clone was determined. To assess the contribution of I-A and I-E subregion-encoded genes to the expression of these restriction elements, helper T cell cultures derived from F1 hybrids between strains with recombinant H-2 haplotypes were analyzed. Parental and unique F1 hybrid MHC determinants that are encoded entirely within the I-A subregion were found to restrict the activity of KLH-specific helper T cells.
mesh_terms: D000818:Animals; D002469:Cell Separation; D002874:Chromosome Mapping; D002999:Clone Cells / Q000276:immunology; D000939:Epitopes; D005815:Genetic Code; D006433:Hemocyanins / Q000276:immunology*; D000949:Histocompatibility Antigens Class II / Q000235:genetics*; D006824:Hybridization, Genetic; D008198:Lymph Nodes / Q000276:immunology; D051379:Mice; D008810:Mice, Inbred C57BL; D011817:Rabbits; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D000939:Epitopes; D000949:Histocompatibility Antigens Class II; D006433:Hemocyanins