GENE-TRANSFER STUDIES OF T-CELL RECEPTOR-GAMMA-DELTA RECOGNITION - SPECIFICITY FOR STAPHYLOCOCCAL ENTEROTOXIN-A IS CONVEYED BY V-GAMMA-9 ALONE

gamma delta T cells bearing the V gamma 9 gene segment have been shown to recognize staphylococcal enterotoxin A (SEA) and a range of other Ags including mycobacterial Ags. We have established an experimental s ystem to analyze the recognition properties of human TCR-gamma delta o n a molecular level by transferring the receptor from its original T c ell into a Jurkat T cell host that does not express an endogenous TCR. Three groups of transfectants that express the same delta-chain, V de lta 1, but different gamma-chains (V gamma 9-J2-C gamma 2, V gamma 3-J 2-C gamma 2, and V gamma 9-JP-C gamma 1)(3) together with the endogeno us CD3 were obtained. The transfectant T cells each expressing differe nt gamma delta receptors all produced IL-2 after stimulation with plas tic bound anti-CD3 Ab, but only those expressing V gamma 9 responded t o stimulation with SEA in the presence of an autologous lymphoblastoid B cell line. In addition, transfectants that expressed V delta 2 comb ined with V gamma 9 could also respond to SEA. These results indicate that the V gamma 9 portion of the receptor, independent of the J regio n and C region or the delta-chain, is responsible for recognizing SEA.