Ren Shoufeng, Wei Qimei, Cai Liya, Yang Xuejing, Xing Cuicui, Tan Feng, Leavenworth Jianmei W, Liang Shaohui, Liu Wenquan
Department of Human Parasitology, Wenzhou Medical University, Wenzhou, China.
Institute of Pathogen and Immunology, Wenzhou Medical University, Wenzhou, China.
Front Microbiol. 2018 Jan 10;8:2662. doi: 10.3389/fmicb.2017.02662. eCollection 2017.
Ebola virus (EBOV) causes severe hemorrhagic fevers in humans, and no approved therapeutics or vaccine is currently available. Glycoprotein (GP) is the major protective antigen of EBOV, and can generate virus-like particles (VLPs) by co-expression with matrix protein (VP40). In this study, we constructed a recombinant Alphavirus Semliki Forest virus (SFV) replicon vector DREP to express EBOV GP and matrix viral protein (VP40). EBOV VLPs were successfully generated and achieved budding from 293 cells after co-transfection with DREP-based GP and VP40 vectors (DREP-GP+DREP-VP40). Vaccination of BALB/c mice with DREP-GP, DREP-VP40, or DREP-GP+DREP-VP40 vectors, followed by immediate electroporation resulted in a mixed IgG subclass production, which recognized EBOV GP and/or VP40 proteins. This vaccination regimen also led to the generation of both Th1 and Th2 cellular immune responses in mice. Notably, vaccination with DREP-GP and DREP-VP40, which produces both GP and VP40 antigens, induced a significantly higher level of anti-GP IgG2a antibody and increased IFN-γ secreting CD8 T-cell responses relative to vaccination with DREP-GP or DREP-VP40 vector alone. Our study indicates that co-expression of GP and VP40 antigens based on the SFV replicon vector generates EBOV VLPs , and vaccination with recombinant DREP vectors containing GP and VP40 antigens induces Ebola antigen-specific humoral and cellular immune responses in mice. This novel approach provides a simple and efficient vaccine platform for Ebola disease prevention.
埃博拉病毒（EBOV）可导致人类严重出血热，目前尚无获批的治疗方法或疫苗。糖蛋白（GP）是EBOV的主要保护性抗原，可通过与基质蛋白（VP40）共表达产生病毒样颗粒（VLPs）。在本研究中，我们构建了一种重组甲病毒塞姆利基森林病毒（SFV）复制子载体DREP，以表达EBOV GP和基质病毒蛋白（VP40）。在用基于DREP的GP和VP40载体（DREP-GP+DREP-VP40）共转染后，成功产生了EBOV VLPs，并从293细胞中出芽。用DREP-GP、DREP-VP40或DREP-GP+DREP-VP40载体对BALB/c小鼠进行疫苗接种，随后立即进行电穿孔，可产生混合的IgG亚类产物，其可识别EBOV GP和/或VP40蛋白。这种疫苗接种方案还导致小鼠产生Th1和Th2细胞免疫反应。值得注意的是，与单独用DREP-GP或DREP-VP40载体进行疫苗接种相比，用产生GP和VP40两种抗原的DREP-GP和DREP-VP40进行疫苗接种可诱导产生显著更高水平的抗GP IgG2a抗体，并增加分泌IFN-γ的CD8 T细胞反应。我们的研究表明，基于SFV复制子载体共表达GP和VP40抗原可产生EBOV VLPs，用含有GP和VP40抗原的重组DREP载体进行疫苗接种可诱导小鼠产生埃博拉抗原特异性体液和细胞免疫反应。这种新方法为预防埃博拉疾病提供了一个简单有效的疫苗平台。
