乙脑/登革2型嵌合病毒的构建及其作为疫苗候选株的初步检定  

Construction and preliminary quality control of Japanese encephalitis/dengue serotype 2 chimeric virus as a candidate vaccine strain

作　　者：牟建超[1] 范凤鸣 陈智[1] 冯劲松 何婷[1] 杨欢 杨会强[1] 曾献武[1] 刘杰[1] MOU Jian-chao;FAN Feng-ming;CHEN Zhi;FENG Jin-song;HE Ting;YANG Huan;YANG Hui-qiang;ZENG Xian-wu;LIU Jie(Chengdu Institute of Biological Products Co.,Ltd.,Chengdu 610023,Sichuan Province,China)

机构地区：[1]成都生物制品研究所有限责任公司

出　　处：《中国生物制品学杂志》2018年第12期1300-1304,共5页Chinese Journal of Biologicals

基　　金：重大新药创制科技重大专项(2018ZX09201006);863计划重大项目(2012AA02A401)

摘　　要：目的构建以乙脑疫苗株SA14-14-2为基因骨架的乙脑/登革2型嵌合病毒,并进行初步检定,分析其作为疫苗候选株的可行性。方法用登革病毒(dengue virus,DENV)减毒株PDK53 prME基因替换乙脑病毒疫苗株SA14-14-2的相应区域,构建乙脑/登革2型嵌合病毒全长克隆质粒,通过体外转录、转染原代地鼠肾(PHK)细胞,拯救出乙脑/登革2型嵌合病毒,并分析该嵌合病毒的蚀斑特征、增殖特征、神经毒力和神经侵袭力、免疫原性及免疫攻击保护作用。结果构建的嵌合病毒比乙脑疫苗株SA14-14-2具有更小的蚀斑,在PHK细胞上具有更低的增殖能力;对成鼠无神经毒力和神经侵袭力;可诱导小鼠产生较高的中和抗体效价,且免疫8周后,中和抗体滴度无明显下降(P> 0. 05);能保护小鼠免受致死剂量DENV的脑内攻击。结论本实验制备的嵌合病毒具有良好的安全性、免疫原性及免疫保护作用,有望作为登革疫苗候选株。Objective To construct Japanese encephalitis/dengue chimeric(JD2) virus using JE virus(JEV) vaccine strain SA14-14-2 as the genetic skeleton. Methods The corresponding region of genome of strain SA14-14-2 was replaced by the pr ME gene of attenuated dengue virus PDK53 strain to construct the full-length cloning plasmid of JD2,followed by in vitro transcription and transfection of primary hamster kidney(PHK)cells to rescue JD2 chimeric virus,of which the characteristics of plaque and proliferation as well as neurovirulence,neuroinvasiveness,immunogenicity and immune protection were evaluated. Results The plaque of JD2 virus was smaller,while the proliferation ability in PHK cells was lower,than those of strain SA14-14-2. No neurovirulence and neuroinvasiveness were observed in adult mice.However,high neutralizing antibody titer was induced in mice,which showed no significant decrease 8 weeks after immunization(P > 0. 05). The chimeric virus protected mice against a lethal challenge with dengue virus by intracerebral route in mice. Conclusion The JD2 chimeric virus showed good safety,immunogenicity and immune protection,which was a promising candidate strain for dengue vaccine.

关 键 词：乙型脑炎病毒 登革病毒 嵌合疫苗 神经毒力 免疫原性 免疫保护 

分 类 号：R373.3[医药卫生—病原生物学] R392.33[医药卫生—基础医学]