SARS-CoV-2S蛋白mRNA疫苗对不同毒株交叉中和活性的研究  

Cross-neutralization activity of mRNA vaccine of SARS-CoV-2 S protein against different variants

作　　者：童菲 赵蕊蕊[1] 张润芳 张凤莲 刘懿萱 乔秋榕 刘婧[1] 钏鸿云 徐丽兰[1] 沈霏[1] 代小虎[1] 马雪峰 宋绍辉[1] 解云 洪超[1] 吴雅楠[1] 周健[1] 廖国阳[1] TONG Fei;ZHAO Ruirui;ZHANG Runfang;ZHANG Fenglian;LIU Yixuan;QIAO Qiurong;LIU Jing;CHUAN Hongyun;XU Lilan;SHEN Fei;DAI Xiaohu;MA Xuefeng;SONG Shaohui;XIE Yun;HONG Chao;WU Yanan;ZHOU Jian;LIAO Guoyang(Institute of Medical Biology,Chinese Academy of Medical Science and Peking Union Medical College,Kunming 650118,Yunnan,China;Kunming Medical University,Kunming 650500,Yunnan,China)

机构地区：[1]中国医学科学院北京协和医学院医学生物学研究所,云南昆明650118 [2]昆明医科大学,云南昆明650500

出　　处：《云南大学学报（自然科学版）》2024年第4期785-792,共8页Journal of Yunnan University(Natural Sciences Edition)

基　　金：中国医学科学院医学与健康科技创新工程(2021-I2M-1-043).

摘　　要：新型冠状病毒(SARS-CoV-2)在感染和持续性进化过程中不断发生变异,导致现有疫苗的有效性降低,因此人类迫切需要能够建立广谱免疫保护的有效疫苗.作者采用mRNA疫苗技术,设计了原型(Prototype)株刺突(Spike,S)蛋白mRNA疫苗(P0).在S蛋白基因序列中引入氨基酸突变位点,制备了Prototype-mut mRNA疫苗P1~P7,并对小鼠进行了免疫.结果表明,引入Q498R-Y505H-H655Y和Q498R-N501Y突变位点的S蛋白mRNA疫苗可以显著提升对Delta株的中和抗体(neutralizing antibody,NAb)滴度(P<0.05).引入Q493R-Q498R-H655Y和Q498R-N501Y突变疫苗对Prototype、Alpha、Beta、Delta、Omicron BA.1等多个毒株的几何平均滴度(geometric mean titer,GMT)分别为1∶194.0、1∶73.5、1∶32.0、1∶194.0、1∶16.0和1∶294.1、1∶294.1、1∶64.0、1∶256.0、1∶8.0.同时,引入Q493R-Q498R-H655Y、Q498R-Y505H和Q498R-Y505H-H655Y等突变疫苗对Prototype、Alpha、Beta、Delta 4种毒株的中和抗体阳转率可达到100%.通过在S蛋白mRNA疫苗中引入点突变的策略,验证了可能具有免疫逃逸或改变受体结合亲和力潜力的氨基酸突变位点的引入对mRNA疫苗交叉中和活性的影响,这为提升mRNA疫苗广谱性的研发提供了参考.The continuous mutation of the SARS-CoV-2 during infection and persistent evolution has led to a decrease in the effectiveness of existing vaccines,and therefore there is an urgent need for effective vaccines capable of establishing broad-spectrum immune protection in humans.The authors used mRNA vaccine technology to design a mRNA vaccine(P0)targeting the spike protein of the Prototype strain.The Prototype-mut mRNA vaccines P1-P7 were prepared by introducing amino acid mutations into the S protein gene sequence and immunized in mice.The results showed that the S protein mRNA vaccines with Q498R-Y505H-H655Y and Q498R-N501Y mutation sites significantly increased the neutralizing antibody(NAb)titer against the Delta strain after the second vaccination(P<0.05).The geometric mean titer(GMT)of the vaccines introducing the Q493R-Q498R-H655Y and Q498R-N501Y mutations against multiple strains of Prototype,Alpha,Beta,Delta,and Omicron BA.1 were 1∶194.0,1∶73.5,1∶32.0,1∶194.0,1.16.0 and 1∶294.1,1∶294.1,1∶64.0,1∶256.0,1∶8.0,respectively.Meanwhile,the vaccines introducing the mutations Q493R-Q498R-H655Y,Q498R-Y505H,and Q498R-Y505H-H655Y could achieve 100%neutralizing antibody positive seroconversion rate against the four strains Prototype,Alpha,Beta,and Delta.Through the strategy of introducing point mutations in S protein mRNA vaccine,the effect of the introduction of amino acid mutation sites that may have the potential for immune escape or alteration of receptor binding affinity on the cross neutralizing activity of mRNA vaccines was verified,which provides a reference for the development of mRNA vaccines to enhance their broad-spectrum properties.

关 键 词：新型冠状病毒 mRNA疫苗 交叉中和活性 氨基酸突变 

分 类 号：R373.1[医药卫生—病原生物学]