LOCALIZATION OF A T-CELL EPITOPE OF SUPERANTIGEN TOXIC-SHOCK-SYNDROMETOXIN-1 TO RESIDUE-125 TO RESIDUE-158

Toxic shock syndrome toxin 1 (TSST-1) is a member of the staphylococca l enterotoxin superantigen family. So far, little is known about T-cel l epitopes on superantigens. In this study, we developed an improved m ethod for localizing T-cell epitopes on superantigens that involved sy nthetic peptides plus costimulation by CD28 or phorbol myristate aceta te. Using this method, we localized a T-cell epitope to a 34-residue r egion, TSST-1 (residues 125 to 158), which possessed only two of four TSST-1-targeted beta-chain variable element (V beta) specificities of T-cell receptors in humans and mice, human V beta 2 and murine V beta 15.