V-BETA-17 GENE POLYMORPHISM IN WILD-DERIVED MOUSE STRAINS - 2 AMINO-ACID SUBSTITUTIONS IN THE V-BETA-17 REGION GREATLY ALTER T-CELL RECEPTOR SPECIFICITY

Of 41 wild-derived mouse strains analyzed, 14 contained T cells bearing Vβ17 receptors in splte of the concomitant expression of I-E antigens. Reciprocal F1 and F2 hybrids of one of these strains, PWK, with laboratory strains revealed different patterns of Vβ17 T cell deletions from those observed with Vβ17 T cells from SJL, implying that the two Vβ17 regions are associated with recognition of distinct superantigens. The structures of the Vβ17 alleles differ by two amino acid substitutions, which lie together in an area distant from the predicted site of T cell receptor interaction with peptide-MHC complexes but overlapping with that implicated in Vβ8.2 recognition of Mls-1 superantigen. This demonstrates that the self-superantigen leading to Vβ17 T cell deletion varies with the allele of the receptor gene and confirms that T cell deletions by such ligands involve interactions with a region of the Vβ domain that is distinct from the conventional combining site. © 1990.