2008-2014年GⅡ.4诺如病毒抗原表位进化研究

Evolution of GⅡ.4 norovirus epitopes of Huzhou City during 2008-2014

目的 了解新的GⅡ.4变异株相对于旧变异株在遗传和结构上的选择优势,研究近几年湖州市GⅡ.4型诺如病毒的进化替换规律.方法 收集从2008年到2014年湖州市GⅡ.4型诺如病毒13株,进行全长VP1区的序列测定,通过序列比对分析找到关键的变异位点.结果 湖州地区的GⅡ.4型诺如病毒在七年中经历了3次变异,2008年和2009年的诺如病毒与2006b variant聚成一个分支;2010和2011年检测到的病毒与2010 variant聚成一个分支;最近从2012年底一起暴发疫情中检测到的诺如病毒和2013年、2014年检测到的与国际上最新的2012 variant聚成一个分支.在氨基酸水平,我们找到77个信息位点（540个氨基酸中的14.3％）.其中39个位于P2区,N端4个,S区18个,P1区16个.结论 GⅡ.4型诺如病毒是全球范围内严重的病毒性肠胃炎首要原因.在过去的十几年时间里,诺如病毒GⅡ.4型已经引起了四次世界范围的急性胃肠炎流行暴发.新出现的变异株迅速并完全的替换已经正在流行的变异株.

Objective To obtain more insight into the genetic and structural bases of the selective advantage of new GGⅡ.4 variants over the old GGⅡ.4 variants.Methods We sequenced the complete capsid of 13 full-length GⅡ.4 norovirus virus VP1 region from 2008 to 2014 and find the key variable sites.Results GⅡ.4 norovirus virus has gone though three big variation during the past seven years.The noroviruses in 2008 and 2009 were the 2006b variant; virus detected in 2010 and 2011 were the 2010 variant ; virus detected in 2012-2014 were the latest 2012 variant.At the amino acid level,we found 77 information sites （540 amino acids in the 14.3%）.39 of them located in the P2 region,N-terminal,4; S region,18; P1 region,16.Conclusions GⅡ.4 noroviruses have been recognized as a leading cause of severe viral gastroenteritis worldwide.During the past decades,four worldwide epidemics of acute gastroenteritis caused by emerging variants of GGⅡ.4 noroviruses have been described.Emerging new variant lineages replaced the previously circulating dominant types rapidly and completely.