Molecular analysis of antigen recognition by insulin-specific T-cell hybridomas from B6 wild-type and bm12 mutant mice.
Molecular analysis of the heterodimeric T-cell antigen receptor of insulin-specific class II-restricted T-cell hybridomas (THys) derived from C57BL/6 (B6) wild-type and B6.C-H-2bm12 (bm12) mutant mice revealed that such T cells use a diverse V gene repertoire. Analysis of three THys that use related V genes, however, showed a number of novel features. Two THys that share major histocompatibility complex restriction use V alpha genes that are 98.6% homologous. Two THys sharing the same antigen fine specificity use a particular germ line V beta D beta J beta combination. A 21-base-pair deletion in the 5' segment of the J beta gene occurs in one THy, suggesting a novel mechanism for generating diversity in T-cell antigen receptor beta genes. The first amino acid encoded by N sequences at the V-D junction is conserved in a pair of T cells which recognize identical antigenic epitopes. The implications of these findings for the structural mechanisms underlying major histocompatibility complex-restricted antigen-specific T-cell recognition are discussed.
D000818:Animals; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics; D000939:Epitopes; D000949:Histocompatibility Antigens Class II / Q000276:immunology*; D006825:Hybridomas / Q000276:immunology; D007328:Insulin / Q000276:immunology*; D008285:Major Histocompatibility Complex; D051379:Mice; D008817:Mice, Mutant Strains; D010446:Peptide Fragments / Q000235:genetics; D011948:Receptors, Antigen, T-Cell / Q000235:genetics / Q000502:physiology*; D016693:Receptors, Antigen, T-Cell, alpha-beta; D013601:T-Lymphocytes / Q000276:immunology*
D000939:Epitopes; D000949:Histocompatibility Antigens Class II; D007328:Insulin; D010446:Peptide Fragments; D011948:Receptors, Antigen, T-Cell; D016693:Receptors, Antigen, T-Cell, alpha-beta; D004247:DNA