A long peptide from MELOE-1 contains multiple HLA class II T cell epitopes in addition to the HLA-A*0201 epitope: an attractive candidate for melanoma vaccination

Cancer Immunol Immunother. 2011 Mar;60(3):327-37. doi: 10.1007/s00262-010-0938-6. Epub 2010 Nov 16.

Abstract

CD4(+) T cells contribute importantly to the antitumor T cell response, and thus, long peptides comprising CD4 and CD8 epitopes may be efficient cancer vaccines. We have previously identified an overexpressed antigen in melanoma, MELOE-1, presenting a CD8(+) T cell epitope, MELOE-1(36-44), in the HLA-A*0201 context. A T cell repertoire against this epitope is present in HLA-A*0201+ healthy subjects and melanoma patients and the adjuvant injection of TIL containing MELOE-1 specific CD8(+) T cells to melanoma patients was shown to be beneficial. In this study, we looked for CD4(+) T cell epitopes in the vicinity of the HLA-A*0201 epitope. Stimulation of PBMC from healthy subjects with MELOE-1(26-46) revealed CD4 responses in multiple HLA contexts and by cloning responsive CD4(+) T cells, we identified one HLA-DRβ1*1101-restricted and one HLA-DQβ1*0603-restricted epitope. We showed that the two epitopes could be efficiently presented to CD4(+) T cells by MELOE-1-loaded dendritic cells but not by MELOE-1+ melanoma cell-lines. Finally, we showed that the long peptide MELOE-1(22-46), containing the two optimal class II epitopes and the HLA-A*0201 epitope, was efficiently processed by DC to stimulate CD4(+) and CD8(+) T cell responses in vitro, making it a potential candidate for melanoma vaccination.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antigens, Neoplasm / immunology*
  • CD4-Positive T-Lymphocytes / cytology*
  • CD4-Positive T-Lymphocytes / immunology
  • Cancer Vaccines / immunology*
  • Epitopes, T-Lymphocyte / immunology*
  • HLA-A Antigens / immunology*
  • HLA-A2 Antigen
  • Histocompatibility Antigens Class II / immunology*
  • Humans
  • Leukocytes, Mononuclear / immunology
  • Lymphocyte Activation
  • Melanoma / immunology
  • Melanoma / therapy*
  • Neoplasm Proteins / immunology*
  • Reference Standards

Substances

  • Antigens, Neoplasm
  • Cancer Vaccines
  • Epitopes, T-Lymphocyte
  • HLA-A Antigens
  • HLA-A*02:01 antigen
  • HLA-A2 Antigen
  • Histocompatibility Antigens Class II
  • MELOE-1 antigen, human
  • Neoplasm Proteins