广西鸡源H9N2亚型禽流感病毒分离鉴定及遗传进化分析  

Isolation and identification of H9N2 subtype avian influenza virus from chicken in Guangxi and its genetic evolution

作　　者：张艳雯[1,2] 何永权 吴云月 于冬玲 曾文榜[1] 宁志鹏 ZHANG Yan-wen;HE Yong-quan;WU Yun-yue;YU Dong-ling;ZENG Wen-bang;NING Zhi-peng(Nanning University,Nanning 530200,China;The State Key Laboratory of Virology,Wuhan 430072,China;Nanning Shanfeng Agriculture and Livestock Husbandry Investment Co.,Ltd.,Nanning 530000,China)

机构地区：[1]南宁学院,南宁530200 [2]病毒学国家重点实验室,武汉430072 [3]南宁市山凤农牧投资有限公司,南宁530000

出　　处：《南方农业学报》2018年第4期780-786,共7页Journal of Southern Agriculture

基　　金：病毒学国家重点实验室开放研究基金项目(2016KF008);广西高校中青年教师基础能力提升项目(2017KY1443);南宁市科学研究与技术开发计划项目(20172151-1);南宁市邕宁区科学研究与技术开发计划项目(20170105C)

摘　　要：【目的】明确广西鸡源H9N2亚型禽流感病毒(AIV)的分子遗传变异规律及其对公共卫生安全的影响,为H9亚型禽流感(AI)的防控提供参考依据。【方法】从广西某肉鸡养殖场采集病料,经SPF鸡胚接种进行病毒分离,对初步鉴定为H9亚型AIV分离株的HA、NA、PB2、PB1、PA、NP、M和NS等8个基因片段进行克隆测定及遗传进化分析,同时对分离毒株的生物学特性进行测定。【结果】从广西发病鸡群中分离获得一株H9N2亚型AIV,命名为A/chicken/Guangxi/BT1/2016(H9N2)。分离毒株A/chicken/Guangxi/BT1/2016(H9N2)HA基因的裂解位点为PSRSSR↓GLF,具有典型的低致病性AIV(LPAIV)分子特征,在遗传进化关系上属于4.2.5分支,与国内常用H9N2亚型AIV疫苗株所属的4.2.3分支存在一定差异;其他7个基因也分别来源于不同的AIV亚型。分离毒株A/chicken/Guangxi/BT1/2016(H9N2)同时具备与α-2,3唾液酸和α-2,6唾液酸受体结合的特性,且具有感染人类的潜在风险;其感染鸡群后病毒分布主要集中在气管、肺脏和脾脏,可通过呼吸道和消化道同时排毒,且在攻毒后第1 d即开始排毒,第5 d为排毒高峰。【结论】从广西发病鸡群中分离获得的A/chicken/Guangxi/BT1/2016(H9N2)属于LPAIV,是由不同亚型AIV重组产生的H9N2亚型新毒株,可导致鸡群疫苗免疫失败,且具有感染人类的潜在风险。【Objective】This study determined molecular genetic variation regularity of H9N2 subtype avian influenza virus(AIV)and its effects on public health safety of human so as to provide reference for the prevention and control of H9 subtype avian influenza(AI).【Method】Suspected tissue samples were collected from one chicken farm in Guangxi,viral isolation was performed by inoculating SPF chicken embryo.The virus was preliminarily identified as H9 subtype AIV isolated strain.Then eight gene fragments isolated from H9 subtype AIV including HA,NA,PB2,PB,PA,NP,M and NS were sequenced,and their genetic evolution was analyzed.The biological characteristics of the isolated strain were also determined at the same time.【Result】A H9N2 subtype AIV strain,named A/chicken/Guangxi/BT1/2016(H9N2),was successfully separated from the sick chicken population in Guangxi.The cleavage site of HA gene in A/chicken/Guangxi/BT1/2016(H9N2)was PSRSSR↓GLF,which had typical features of low pathogenic AIV(LPAIV)molecule.In genetic evolution relation,it belonged to 4.2.5 branch,and had some differences with the domestic H9N2 subtype AIV vaccine strains which belonged to 4.2.3 branch.The other seven genes were also derived from different AIV subtypes.The isolated virus strain A/chicken/Guangxi/BT1/2016(H9N2)could bind toα-2,3 sialic acid andα-2,6 sialic acid receptors,with the potential risk to infect human.Virus distribution was mainly concentrated in trachea,lung and spleen after it infected chicken,and the virus also could be released through the respiratory tract and digestive tract at same time.The virus was released from day 1 and peaked on the day 5 after the chicken was infected.【Conclusion】A/chicken/Guangxi/BT1/2016(H9N2),isolated from Guangxi sick chicken population,belonged to LPAIV.It is a H9N2 subtype new virus created by different subtypes AIV.It can lead to the failure of chicken vaccine immunization and has the potential risk of infecting human beings.

关 键 词：禽流感病毒(AIV) H9N2亚型 分离鉴定 遗传进化 裂解位点 受体结合特性 广西 

分 类 号：S858.31[农业科学—临床兽医学]