Yan Yan, Hu Kai, Deng Xu, Guan Xinmeng, Luo Sukun, Tong Lina, Du Tao, Fu Ming, Zhang Mudan, Liu Yalan, Hu Qinxue
State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China; University of Chinese Academy of Sciences, Beijing 100049, China; and.
State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China;
J Immunol. 2015 Jul 1;195(1):329-38. doi: 10.4049/jimmunol.1500198. Epub 2015 May 20.
There is a lack of an HSV-2 vaccine, in part as the result of various factors that limit robust and long-term memory immune responses at the mucosal portals of viral entry. We previously demonstrated that chemokine CCL19 augmented mucosal and systemic immune responses to HIV-1 envelope glycoprotein. Whether such enhanced immunity can protect animals against virus infection remains to be addressed. We hypothesized that using CCL19 in a fusion form to direct an immunogen to responsive immunocytes might have an advantage over CCL19 being used in combination with an immunogen. We designed two fusion constructs, plasmid (p)gBIZCCL19 and pCCL19IZgB, by fusing CCL19 to the C- or N-terminal end of the extracellular HSV-2 glycoprotein B (gB) with a linker containing two (Gly4Ser)2 repeats and a GCN4-based isoleucine zipper motif for self-oligomerization. Following immunization in mice, pgBIZCCL19 and pCCL19IZgB induced strong gB-specific IgG and IgA in sera and vaginal fluids. The enhanced systemic and mucosal Abs showed increased neutralizing activity against HSV-2 in vitro. Measurement of gB-specific cytokines demonstrated that gB-CCL19 fusion constructs induced balanced Th1 and Th2 cellular immune responses. Moreover, mice vaccinated with fusion constructs were well protected from intravaginal lethal challenge with HSV-2. Compared with pgB and pCCL19 coimmunization, fusion constructs increased mucosal surface IgA(+) cells, as well as CCL19-responsive immunocytes in spleen and mesenteric lymph nodes. Our findings indicate that enhanced humoral and cellular immune responses can be achieved by immunization with an immunogen fused to a chemokine, providing information for the design of vaccines against mucosal infection by HSV-2 and other sexually transmitted viruses.
目前缺乏单纯疱疹病毒2型（HSV - 2）疫苗，部分原因是多种因素限制了在病毒进入的黏膜部位产生强大且持久的记忆免疫反应。我们之前证明趋化因子CCL19可增强对HIV - 1包膜糖蛋白的黏膜和全身免疫反应。这种增强的免疫力是否能保护动物免受病毒感染仍有待研究。我们推测，以融合形式使用CCL19将免疫原导向反应性免疫细胞可能比将CCL19与免疫原联合使用具有优势。我们通过将CCL19与细胞外HSV - 2糖蛋白B（gB）的C端或N端融合，并带有包含两个（Gly4Ser）2重复序列和基于GCN4的异亮氨酸拉链基序用于自寡聚化的接头，设计了两种融合构建体，即质粒（p）gBIZCCL19和pCCL19IZgB。在小鼠免疫后，pgBIZCCL19和pCCL19IZgB在血清和阴道分泌物中诱导出强烈的gB特异性IgG和IgA。增强的全身和黏膜抗体在体外对HSV - 2显示出增加的中和活性。对gB特异性细胞因子的检测表明，gB - CCL19融合构建体诱导了平衡的Th1和Th2细胞免疫反应。此外，用融合构建体接种的小鼠在经阴道HSV - 2致死性攻击后得到了良好的保护。与pgB和pCCL19联合免疫相比，融合构建体增加了黏膜表面IgA(+)细胞以及脾脏和肠系膜淋巴结中对CCL19有反应的免疫细胞。我们的研究结果表明，通过用与趋化因子融合的免疫原进行免疫可实现增强的体液和细胞免疫反应，为设计针对HSV - 2和其他性传播病毒黏膜感染的疫苗提供了信息。
