IDENTIFICATION OF A PEPTIDE RECOGNIZED BY 5 MELANOMA-SPECIFIC HUMAN CYTOTOXIC T-CELL LINES

Of several thousand peptides presented by the major histocompatibility molecule HLA-A2.1, at least nine are recognized by melanoma-specific cytotoxic T lymphocytes (CTLs). Tandem mass spectrometry was used to i dentify and to sequenceone of these peptide epitopes. Melanoma-specifi c CTLs had an exceptionally high affinity for this nine-residue peptid e, which reconstituted an epitope for CTL lines from each of five diff erent melanoma patients tested. Recognition bymultiple CTL lines sugge sts that this may be a promising candidate for use inpeptide-based mel anoma vaccines.