Immunotherapy of Epstein-Barr virus associated malignancies using mycobacterial HSP70 and LMP2A356-364 epitope fusion protein

Cell Mol Immunol. 2009 Dec;6(6):423-31. doi: 10.1038/cmi.2009.54.

Abstract

Epstein-Barr virus infection is strongly associated with a number of malignancies. The EBV latent membrane protein 2A has been implicated as one of the most attractive candidates for immunotherapy of related malignancies. In previous studies, the T cell epitopes of LMP2A have been identified systematically. However, the epitope-based vaccine generally meets inefficient immunogenicity when used in vivo directly, which could be overcome by combination with appropriate adjuvants. Heat shock protein is a natural chaperon, which is able to activate the classical major histocompatibility complex class I antigen-processing pathway (cross-presentation). In this study, a minigene encoding LMP2A(356-364) (FLYALALLL) was genetically fused to the carboxy-terminal of mycobacterial heat shock protein 70. The epitope fusion protein was expressed and purified, and the cross-presentation of LMP2A(356-364) by monocyte-derived dendritic cells pulsed with the epitope fusion protein was evaluated. Results showed that the epitope fusion protein-pulsed mDCs were much more efficient than the single peptide-pulsed mDCs on CTL activation. Immunization of HLA-A2.1 transgenic mice with MtHsp70-LMP2A(356-364) generated peptide specific CTL more effectively than a single peptide plus incomplete Freund's adjuvant (IFA). Growth of LMP2A expressing B16 melanoma tumor cells was suppressed in the vaccinated groups. Our results suggested that MtHsp70-LMP2A(356-364) fusion protein was more effective than the CD8(+) T cell epitope alone on anti-tumor immunity. As a result, the MtHsp70-LMP2A(356-364) fusion protein is considered to be a promising candidate vaccine for EBV related malignancies.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Cell Line, Tumor
  • Disease Progression
  • Epitopes / chemistry
  • Epitopes / genetics
  • Epitopes / immunology*
  • HSP70 Heat-Shock Proteins / genetics
  • HSP70 Heat-Shock Proteins / metabolism*
  • Herpesvirus 4, Human / immunology*
  • Immunization*
  • Melanoma / immunology*
  • Melanoma / pathology
  • Melanoma / therapy
  • Mice
  • Mice, Inbred C57BL
  • Neoplasm Transplantation
  • Recombinant Fusion Proteins / chemistry
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / immunology
  • Recombinant Fusion Proteins / metabolism
  • T-Lymphocytes, Cytotoxic / immunology
  • Viral Matrix Proteins / chemistry
  • Viral Matrix Proteins / genetics
  • Viral Matrix Proteins / immunology*

Substances

  • EBV-associated membrane antigen, Epstein-Barr virus
  • Epitopes
  • HSP70 Heat-Shock Proteins
  • Recombinant Fusion Proteins
  • Viral Matrix Proteins