title: Immunotherapy of Epstein-Barr virus associated malignancies using mycobacterial HSP70 and LMP2A356-364 epitope fusion protein.
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.
authors.affiliation: Department of Microbiology and Immunology, Nanjing Medical University, Nanjing 210029, China.
authors.forename: Genyan
authors.initials: G
authors.lastname: Liu
authors.forename: Kun
authors.initials: K
authors.lastname: Yao
authors.forename: Bing
authors.initials: B
authors.lastname: Wang
authors.forename: Yun
authors.initials: Y
authors.lastname: Chen
authors.forename: Feng
authors.initials: F
authors.lastname: Zhou
authors.forename: Yidi
authors.initials: Y
authors.lastname: Guo
authors.forename: Jian
authors.initials: J
authors.lastname: Xu
authors.forename: Hongzhen
authors.initials: H
authors.lastname: Shi
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D045744:Cell Line, Tumor; D018450:Disease Progression; D000939:Epitopes / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism*; D004854:Herpesvirus 4, Human / Q000276:immunology*; D007114:Immunization; D008545:Melanoma / Q000276:immunology* / Q000473:pathology / Q000628:therapy; D051379:Mice; D008810:Mice, Inbred C57BL; D009368:Neoplasm Transplantation; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology; D014763:Viral Matrix Proteins / Q000737:chemistry / Q000235:genetics / Q000276:immunology*
chemical_list: C037662:EBV-associated membrane antigen, Epstein-Barr virus; D000939:Epitopes; D018840:HSP70 Heat-Shock Proteins; D011993:Recombinant Fusion Proteins; D014763:Viral Matrix Proteins