Chimerically fused antigen rich of overlapped epitopes from latent membrane protein 2 （LMP2） of Epstein-Barr virus as a potential vaccine and diagnostic agent  

作　　者：Xiaoyun Lin Shao Chen Xiangyang Xue Lijun Lu Shanli Zhu Wenshu Li Xiangmin Chen Xiaozhi Zhong Pengfei Jiang Torsoo Sophia Sename Yi Zheng Lifang Zhang 

机构地区：[1]Department of Microbiology and Immunology, Institute of Molecular Virology and Immunology, Wenzhou Medical University, Wenzhou, China [2]School of Laboratory Medicine and Life Science, Wenzhou Medical University, Wenzhou, China

出　　处：《Cellular & Molecular Immunology》2016年第4期492-501,共10页中国免疫学杂志（英文版）

基　　金：This work was supported by a grant from the National Natural Science Foundation of China （No： 81372447）.

摘　　要：Epstein-Barr virus （EBV） is prevalent throughout the world and is associated with several malignant diseases in humans. Latent membrane protein 2 （LMP2） of EBV plays a crucial role in the pathogenesis of EBV-associated tumors; therefore, LMP2 has been considered to be a potential immunodiagnostic and immunotherapeutic target. A multi-epitope-based antigen is a promising option for therapeutic vaccines and diagnoses of such malignancies. In this study, we systematically screened cytotoxic T lymphocyte （CTL）, helper T cell （Th） and B-cell epitopes within EBV-LMP2 using bioinformatics. Based on the screen, two peptides rich in overlapping epitopes of both T cells and B cells were selected to construct a plasmid containing the sequence for a chimeric multi-epitope protein referred to as EBV-LMP2m, which is composed of LMP2aa195-232 and LMP2aa419-436. The EBV-LMP2m protein was expressed in E. coil BL21 （DE3） after prokaryotic codon optimization. Inoculation of the purified chimeric antigen in BALB/c mice induced not only high levels of specific IgG in the serum and secretory IgA in the vaginal mucus but also a specific CTL response. By using purified EBV-LMP2m as an antigen, the presence of specific IgG in the serum specimens of 202 nasopharyngeal carcinoma （NPC） patients was effectively detected with 52.84% sensitivity and 95.40% specificity, which represents an improvement over the traditional detection method based on VCA-IgA （60.53% sensitivity and 76.86% specificity）. The above results indicate that EBV-LMP2m may be used not only as a potential target antigen for EBV-associated tumors but also a diagnostic agent for NPC patients.Epstein-Barr virus （EBV） is prevalent throughout the world and is associated with several malignant diseases in humans. Latent membrane protein 2 （LMP2） of EBV plays a crucial role in the pathogenesis of EBV-associated tumors; therefore, LMP2 has been considered to be a potential immunodiagnostic and immunotherapeutic target. A multi-epitope-based antigen is a promising option for therapeutic vaccines and diagnoses of such malignancies. In this study, we systematically screened cytotoxic T lymphocyte （CTL）, helper T cell （Th） and B-cell epitopes within EBV-LMP2 using bioinformatics. Based on the screen, two peptides rich in overlapping epitopes of both T cells and B cells were selected to construct a plasmid containing the sequence for a chimeric multi-epitope protein referred to as EBV-LMP2m, which is composed of LMP2aa195-232 and LMP2aa419-436. The EBV-LMP2m protein was expressed in E. coil BL21 （DE3） after prokaryotic codon optimization. Inoculation of the purified chimeric antigen in BALB/c mice induced not only high levels of specific IgG in the serum and secretory IgA in the vaginal mucus but also a specific CTL response. By using purified EBV-LMP2m as an antigen, the presence of specific IgG in the serum specimens of 202 nasopharyngeal carcinoma （NPC） patients was effectively detected with 52.84% sensitivity and 95.40% specificity, which represents an improvement over the traditional detection method based on VCA-IgA （60.53% sensitivity and 76.86% specificity）. The above results indicate that EBV-LMP2m may be used not only as a potential target antigen for EBV-associated tumors but also a diagnostic agent for NPC patients.

关 键 词：Epstein-Barr virus （EBV） EPITOPE latent membrane protein 2 （LMP2） VACCINE 

分 类 号：Q78[生物学—分子生物学] Q556.3