Identification of a shared epitope recognized by melanoma-specific, HLA-A3-restricted cytotoxic T lymphocytes.
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.
Hogan
Kevin T
KT
Department of Surgery, University of Virginia, Box 801359, Charlottesville, VA 22908, USA. kh6s@virginia.edu
Coppola
Michael A
MA
Gatlin
Christine L
CL
Thompson
Lee W
LW
Shabanowitz
Jeffrey
J
Hunt
Donald F
DF
Engelhard
Victor H
VH
Slingluff
Craig L
CL
Ross
Mark M
MM
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*
D002860:Chromium Radioisotopes; D018984:Epitopes, T-Lymphocyte; D015791:HLA-A3 Antigen; D010455:Peptides