title: Identification of a shared epitope recognized by melanoma-specific, HLA-A3-restricted cytotoxic T lymphocytes.
abstract: We previously established a melanoma-reactive cytotoxic T lymphocyte (CTL) line that recognizes multiple epitopes in the context of HLA-A3. To increase the number of peptides available for use in a vaccine for the treatment of melanoma, we identified one of these epitopes, SQNFPGSQK, through a combination of epitope reconstitution experiments and mass spectrometry. The SQNFPGSQK peptide was also found to be associated with HLA-A3 on an additional melanoma tumor line, thus indicating that the peptide is not unique to the melanoma tumor line from which it was isolated and thus, unlikely to arise through a mutational event. Although the protein origin of SQNFPGSQK has yet to be established, the shared nature of this epitope and the fact that it elicits a natural immune response indicates that it warrants further study to determine its usefulness as a vaccine component for the treatment of melanoma. The peptide may also be useful as a research tool for evaluating spontaneous anti-tumor immune responses in patients with melanoma.
authors.affiliation: Department of Surgery, University of Virginia, Box 801359, Charlottesville, VA 22908, USA. kh6s@virginia.edu
authors.forename: Kevin T
authors.initials: KT
authors.lastname: Hogan
authors.forename: Michael A
authors.initials: MA
authors.lastname: Coppola
authors.forename: Christine L
authors.initials: CL
authors.lastname: Gatlin
authors.forename: Lee W
authors.initials: LW
authors.lastname: Thompson
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Shabanowitz
authors.forename: Donald F
authors.initials: DF
authors.lastname: Hunt
authors.forename: Victor H
authors.initials: VH
authors.lastname: Engelhard
authors.forename: Craig L
authors.initials: CL
authors.lastname: Slingluff
authors.forename: Mark M
authors.initials: MM
authors.lastname: Ross
mesh_terms: D000595:Amino Acid Sequence; D045744:Cell Line, Tumor; D002851:Chromatography, High Pressure Liquid; D002860:Chromium Radioisotopes; D018984:Epitopes, T-Lymphocyte / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D015791:HLA-A3 Antigen / Q000276:immunology*; D006801:Humans; D013058:Mass Spectrometry; D008545:Melanoma / Q000276:immunology*; D010455:Peptides / Q000737:chemistry / Q000235:genetics / Q000276:immunology; D017385:Sequence Homology; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*
chemical_list: D002860:Chromium Radioisotopes; D018984:Epitopes, T-Lymphocyte; D015791:HLA-A3 Antigen; D010455:Peptides