广州地区丙型肝炎病毒主要基因型E1蛋白胞外域序列分析  

Sequencing of the glycoprotein E1 ectodomain of hepatitis C virus prevalent in the Guangzhou area

作　　者：杜荣松 许茹[2,3] 黄杰庭[2,3] 王敏 廖峭[2,3] 单振刚 戎霞[2,3] 王淏 郑优荣[2] 付涌水 DU Rong-song;XU Ru;HUANG Jie-ting;WANG Min;LIAO Qiao;SHAN Zhen-gang;RONG Xia;WANG Hao;ZHENG You-rong;FU Yong-shui(Department of Transfusion Medicine,School of Laboratory Medicine and Biotechnology,Southern Medical University,Guangzhou,Guangdong,China 510515;Guangzhou Blood Center;The Key Medical Disciplines and Specialties Program of Guangzhou)

机构地区：[1]南方医科大学检验与生物技术学院输血医学系,广东广州510515 [2]广州血液中心 [3]广州市医学重点实验室(血液安全重点实验室)

出　　处：《中国病原生物学杂志》2020年第11期1241-1245,1256,共6页Journal of Pathogen Biology

基　　金：国家自然科学基金项目(No.81772208);广东省医学科学技术研究基金项目(No.B2020090);广州市医学重点学科建设项目(血液安全重点实验室)。

摘　　要：目的了解广州地区丙型肝炎病毒(HCV)主要流行基因型E1蛋白胞外域氨基酸序列突变特征。方法采集2012-2018年380例广州地区HCV感染者血液标本,使用试剂盒提取HCV RNA,进行Core/E1区序列巢式PCR扩增和测序,采用Mega 7.0构建系统进化树进行基因分型,对广州地区流行的HCV主要基因型的E1胞外域部分序列进行氨基酸翻译和构建共有序列,利用生物信息软件、统计软件分析HCV E1胞外域氨基酸位点突变的分布特征、替换模式及与宿主免疫的关系。结果广州地区HCV主要流行基因型为1b和6a,分别占38.68%和41.84%;1b和6a基因型E1蛋白胞外域(aa 192-320)发生突变的氨基酸位点分别有62个(48.1%)和60个(46.5%),差异无统计学意义(χ^2=2.04,P>0.05);突变主要发生在aa 192-260区段,1b型的高度突变位点(突变率≥20%)比较分散,6a型则集中在aa231-243区段;高度突变位点均处于免疫表位区,BLOSUM评分显示大部分突变位点氨基酸替换模式为保守性替换。结论HCV基因型1b和6a蛋白E1胞外域的高度突变位点主要位于免疫表位区,大部分突变为保守性替换而且种类多样,可能与免疫压力有关。Objective To examine potential amino acid mutations and to ascertain the molecular characteristics of the viral glycoprotein E1 ectodomain of predominant HCV genotypes in Guangzhou,China.Methods Blood samples were collected from 380 volunteers at the Guangzhou Blood Center who were HCV RNA-positive.The sequence of the HCV E1 N-terminal ectodomain was amplified using nested PCR and sequenced.Subtypes were assigned based on a phylogenetic tree constructed using the neighbor-joining method,and amino acid translation was performed using Mega 7.0.Amino acid substitution was analyzed with bioinformatic software(MutationMaster)and SPSS 20.0.Results A total of 380 infected individuals were genotyped and six HCV subtypes were detected,including 1 a(6),1 b(147),2 a(20),3 a(24),3 b(24),and 6 a(159).The predominant HCV genotypes in Guangzhou were 6 a(41.84%)and 1 b(38.68%).In the ectodomain of E1(amino acids 192-320),60 amino acids(46.5%)varied in genotype 6 awhile 62 amino acids(48.1%)varied in in genotype 1 b.The variance in amino acids between subtype 6 aand 1 bwas not significant(χ^2=2.04,P>0.05).Mutations mainly occurred in amino acids 192-260.Frequent mutations were scattered in HCV 1 bbut concentrated in amino acids 231-243 in HCV 6 a.Frequent mutations were in the immunoreactive epitope region and most were conserved,with a zero or positive BLOSUM score.Conclusion Frequent mutations of amino acids in the HCV 1 band 6 a E1 ectodomain were mainly in amino acids 192-260.Most of the mutations were conserved substitutions of various types,which may be related to host immune stress.

关 键 词：丙型肝炎病毒 基因型 突变 疫苗 

分 类 号：R373.21[医药卫生—病原生物学]