HLA-G as a target molecule in specific immunotherapy against renal cell carcinoma

Oncol Rep. 2007 Dec;18(6):1463-8.

Abstract

The human leukocyte antigen (HLA)-G molecule can exert immunoregulatory functions. However, its limited tissue distribution and preferential expression in a variety of malignancies suggest the possibility that it could be a target in anti-cancer immunotherapy. In the present study, we tested this possibility by focusing on renal cell carcinoma (RCC) patients, especially those with HLA-A24 alleles. Four HLA-G-derived peptides were prepared based on the binding motif to the HLA-A24 alleles. After a stabilization assay confirmed the binding of these peptides to HLA-A24 molecules, they were screened for the capacity to induce peptide-specific cytotoxic T lymphocytes (CTLs) from peripheral blood mononuclear cells (PBMCs) of HLA-A24+ RCC cancer patients. As a result, the HLA-G(146-154) peptide was found to effectively induce peptide-specific CTLs, and HLA-G(146-154) peptide-stimulated PBMCs exhibited cytotoxic activity against HLA-G-expressing HLA-A24+ RCC cells. Antibody blocking and cold inhibition experiments confirmed that the cytotoxicity was partially ascribed to peptide-specific and HLA class I-restricted CD8+ T cells. These results indicate that HLA-G-associated immunoregulation can be overcome and that HLA-G peptide-based anti-cancer immunotherapy is feasible.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Carcinoma, Renal Cell / genetics
  • Carcinoma, Renal Cell / immunology*
  • Carcinoma, Renal Cell / pathology
  • Cell Line, Tumor
  • Flow Cytometry
  • HLA Antigens / immunology*
  • HLA-A Antigens / genetics
  • HLA-A24 Antigen
  • HLA-G Antigens
  • Histocompatibility Antigens Class I / immunology*
  • Humans
  • Immunotherapy / methods*
  • Interferon-gamma / pharmacology
  • Kidney Neoplasms / genetics
  • Kidney Neoplasms / immunology*
  • Kidney Neoplasms / pathology
  • Peptide Fragments
  • T-Lymphocytes, Cytotoxic / drug effects
  • T-Lymphocytes, Cytotoxic / immunology

Substances

  • HLA Antigens
  • HLA-A Antigens
  • HLA-A24 Antigen
  • HLA-G Antigens
  • Histocompatibility Antigens Class I
  • Peptide Fragments
  • Interferon-gamma