EVIDENCE THAT THE ANTIGEN RECEPTORS OF CYTOTOXIC T-LYMPHOCYTES INTERACT WITH A COMMON RECOGNITION PATTERN ON THE H-2K(B) MOLECULE

Recognition of class I MHC antigens involves interaction between TCRs of cytotoxic T lymphocytes (CTL) and the two alpha helices of MHC molecules. Using a combined panel of H-2K(b) mutants selected by either a CTL clone or MAbs, we have shown evidence that the TCRs of 59 K-b-specific CTL clones shared a common binding pattern on the H-2K(b) molecule. Mutations of amino acid residues at the C-terminal regions, but not the N-terminal regions, of the a helices abrogated the recognition by the majority of the clones. The data suggests that TCRs predominantly recognize the class I MHC molecule with an orientation that is parallel to the beta-pleated strands and diagonal to the alpha helices.