SHARED T-CELL EPITOPES IN EPITHELIAL TUMORS

we have previously shown the importance of human leukocyte antigen (HL A)-A2 and the proto-oncogene HER2/neu in the T cell recognition of ova rian cancer, Since these proteins are ubiquitously expressed in epithe lial-derived tumors, we have acid-eluted HLA-bound peptides from ovari an cancers, fractionated the peptides, and reconstituted T cell epitop es on the HLA-A2(+) T2 cell line to determine if common tumor-associat ed antigens exist among HLA-A2(+), HER2/neu(+) epithelial cancers. We demonstrate that tumor-specific cytotoxic T lymphocytes (CTL) generate d from tumorinfiltrating lymphocytes isolated from three ovarian, two breast, and two non-small-cell lung cancers recognize at least three o f the same peptide fractions from multiple elutions, One of these pept ide fractions coelutes with a HERS/neu-derived peptide which has been shown recently to be recognized by these same CTL, These findings demo nstrate that a common peptide-based tumor vaccine is theoretically pos sible for many different epithelial-derived cancers. (C) 1995 Academic Press, Inc.