SARS病毒S蛋白受体结合区DNA疫苗及免疫效果研究  

Construction of a DNA vaccine encoding the receptor-binding domain of SARS-CoV spike protein and its immune effects

作　　者：谢力[1] 肖文珺[1] 管洁[1] 于虹[1] 赵瑞景[2] 周育森[1] 

机构地区：[1]军事医学科学院微生物流行病研究所病原微生物生物安全国家重点实验室,北京100071 [2]河北医科大学免疫学教研室,石家庄050017

出　　处：《免疫学杂志》2007年第2期131-134,共4页Immunological Journal

基　　金：北京科委中英SARS免疫病理学研究基金项目资助(H030230100130)

摘　　要：目的研究SARS冠状病毒(SARS-CoV)靶细胞受体结合区所构建之DNA疫苗的免疫效果,为进一步的SARS-CoV免疫机理研究及疫苗研制奠定基础。方法选取SARS-CoVS基因包含靶细胞受体结合区和S1亚单位C端2个基因片段作为目的基因,构建真核表达质粒pVAX-RBD(receptor binding domain)、pVAX-S1C作为DNA疫苗免疫BALB/c小鼠,检测其特异性体液免疫及细胞免疫情况。结果体液免疫方面,以SARS全病毒裂解产物和原核表达的RBD蛋白作为诊断抗原,用ELISA均可检测到高滴度的小鼠血清抗体IgG的产生。而且,血清中和试验显示pVAX-RBD质粒激发了小鼠保护性中和抗体的产生。通过流式细胞分析和酶联免疫斑点实验(ELISPOT)检测,pVAX-RBD和pVAX-S1C两组质粒均诱导免疫小鼠产生了特异性细胞免疫反应。结论证明SARS-CoVS蛋白受体结合区上中和表位的存在;体液免疫在抗SARS-CoV感染方面起到重要作用。Objective To investigate immune response of the DNA vaccine encoding receptor-binding domain of SARS-coronavirus （SARS-CoV） and its immune effects for exploring the immune mechanisms of SARS-CoV and developing vaccines. Methods Two kinds of truncated S protein gene fragments were cloned into eukazyotie expression domain （RBD） and S1 subunit C terminal （S1C）, respectively. Balb/ e mice were immunized with the two DNA vaccines pVAX-RBD and pVAX-S1C and the speeific humoral and cell-mediated immune responses were detected by flow cytometry （FCM） and enzyme-linked immunosopt （ELSPOT）. Results Mouse sere IgG antibodies with high titer were detected by enzyme-linked imnmnosorbent assay （ ELISA）, with E. coli-expressed protein RBD or SARS-CoV lysate as diagnostic antigen. Furthennore, neutralizing antibodies were also detected in mice vaccinated with the plasmid pVAX-RBD containing the receptor-binding domain. The two expression plasmids could induce some speeiiie cell-mediated immune responses. Conclusion It is proved that the existence of neutralizing epitope in S protein receptor-binding domain; in addition, humoml immunity plays a significant role in preventing virus infection, while the effect of ceil-mediated immune is uncertain and need to be further study.

关 键 词：SARS冠状病毒 S蛋白 受体结合区 中和抗体 DNA疫苗 

分 类 号：R392.1[医药卫生—免疫学]