Identification of HLA-A2- and A24-restricted T-cell epitopes derived from SOX6 expressed in glioma stem cells for immunotherapy.

Abstract

Malignant gliomas are the most aggressive human primary brain tumors and are currently incurable. Immunotherapies have the potential to target glioma and glioma stem cells (GSCs) that are resistant to conventional therapies. We previously identified SOX6 as a human glioma antigen and demonstrated that vaccination with SOX6 DNA induced cytotoxic T lymphocytes (CTLs) specific for glioma, thereby exerting therapeutic antitumor responses in glioma-bearing mice. In this study, we attempted to identify SOX6-derived peptides as specific targets for effective and safe T-cell-mediated immunotherapy targeting SOX6-positive glioma and GSCs. In vitro stimulation with human leukocyte antigen (HLA)-A*2402 (A24)-restricted peptides, RFENLGPQL (SOX6(504)) and PYYEEQARL (SOX6(628)) or the HLA-A*0201 (A2)-restricted peptide, ALFGDQDTV (SOX6(447)) was capable of inducing SOX6 peptide-specific CTLs in peripheral blood mononuclear cells derived from healthy donors and glioma patients. These CTLs were able to lyse a majority of glioma cell lines and a GSC line derived from human glioblastoma in an HLA Class I-restricted and an antigen-dependent manner. Furthermore, peptide vaccines of SOX6(628), which was conserved in the murine SOX6 protein and expected to bind to major histocompatibility complex (MHC) H-2(d), induced CTLs specific for SOX6(628) in H-2(d) mice. Normal autologous cells from mice, in which SOX6-specific immune responses were generated, were not destroyed. These results suggest that these SOX6 peptides are potnetially immunogenic in HLA-A24 or -A2 positive glioma patients and should be considered as a promising strategy for safe and effective T-cell-based immunotherapy of patients with gliomas.

• Authors: Ryo Ueda, Kozo Ohkusu-Tsukada, Noemi Fusaki, Akio Soeda, Takeshi Kawase, Yutaka Kawakami, Masahiro Toda
• Journal: International journal of cancer (Int J Cancer) Vol. 126 Issue 4 Pg. 919-29 (Feb 15 2010) ISSN: 1097-0215 [Electronic] United States
• PMID: 19728337 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Epitopes
• HLA-A Antigens
• HLA-A2 Antigen
• HLA-A24 Antigen
• HLA-B Antigens
• Peptide Fragments
• SOX6 protein, human
• SOXD Transcription Factors

Topics

• Adult
• Animals
• Brain (immunology, pathology)
• Brain Neoplasms (epidemiology, immunology, pathology)
• Cell Survival (immunology)
• Epitopes (immunology)
• Female
• Glioma (epidemiology, immunology, pathology)
• HLA-A Antigens (genetics, immunology)
• HLA-A2 Antigen (immunology)
• HLA-A24 Antigen
• HLA-B Antigens (genetics)
• Humans
• Immunotherapy (methods)
• Male
• Mice
• Peptide Fragments (immunology)
• SOXD Transcription Factors (genetics, immunology)
• Stem Cells (immunology)
• T-Lymphocytes (immunology)
• T-Lymphocytes, Cytotoxic (immunology, pathology)
• United States (epidemiology)
• Young Adult