ANTIGEN RECOGNITION PROPERTIES OF MUTANT V-BETA-3+ T-CELL RECEPTORS ARE CONSISTENT WITH AN IMMUNOGLOBULIN-LIKE STRUCTURE FOR THE RECEPTOR

We examined the effect of mutations in the Vbeta portion of a pigeon cytochrome c (cyto c)-specific Vbeta3+/Valpha11+ T cell receptor on its ability to recognize cyto c/IE(k) and various superantigens. The results were consistent with an immunoglobulin-like structure for the receptor Vbeta domain and with separate interaction sites on Vbeta for conventional antigen and superantigens. An amino acid predicted to lie in CDR1 was critical for cyto c/IE(k) but not superantigen recognition, while several amino acids predicted to lie in the hypervariable region 4 loop were critical for superantigen but not cyto c/IE(k) recognition.