江苏省首例人感染H9N2禽流感的发现及病毒血凝素基因特征分析  

Hemagglutinin gene characteristics of the H9N2 avian influenza virus from the first patient infected with this virus in Jiangsu province

作　　者：董泽丰 刘成[1] 雅雪蓉 王笛 沈强[1] 夏瑜[1] Dong Zefeng;Liu Cheng;Ya Xuerong;Wang Di;Shen Qiang;Xia Yu(Suzhou Center for Disease Control and Prevention,Suzhou 215004,China)

机构地区：[1]苏州市疾病预防控制中心,215004

出　　处：《中华实验和临床病毒学杂志》2021年第3期276-279,共4页Chinese Journal of Experimental and Clinical Virology

基　　金：苏州市"科教兴卫"青年科技项目(KJXW2017051);苏州科技局—民生科技项目(SYS201780);苏州市民生科技发展计划项目(SS202073);苏州市重大疾病、传染病预防和控制关键技术项目(GWZX202002);姑苏卫生人才计划青年拔尖人才项目(GSWS2020099);苏州市科技局第一批科技发展项目(SYS202006)。

摘　　要：目的了解江苏省首例人感染H9N2亚型禽流感病例的流行病学特点和相应H9N2禽流感病毒血凝素(hemagglutinin,HA)基因特征。方法逆转录聚合酶链反应(reverse transcription polymerase chain reaction,RT-PCR)方法检测不明原因急重症呼吸道感染病例咽拭子标本甲/乙型及各亚型流感病毒核酸。Sanger法对H9N2阳性标本进行病毒HA基因测序,与禽流感病毒数据库中的参考序列进行比对分析。构建HA基因系统进化树。结果苏州市疾病预防控制中心于2019年3月报告了江苏省首例人感染H9N2亚型禽流感病毒实验室确诊病例。HA基因序列分析表明苏州A/Suzhou/S683/2019(H9N2)病毒株为欧亚谱系Y280-like亚系分支,与A/chicken/Shanghai/S1171/2018(H9N2)核酸序列同源性最高,为99.23%。HA蛋白裂解位点氨基酸序列为PSRSSR↓GLF,并且受体结合位点关键氨基酸中发生了Q226L突变。与F98疫苗株相比,该禽流感病毒HA潜在糖基化位点位置发生了一定程度的改变。结论苏州H9N2禽流感病毒仍为低致病性,但可能获得了适应人类宿主的部分能力。Objective To disclose the epidemiological characteristics of the first human case of H9N2 subtype avian influenza and genetic characteristics of hemagglutinin(HA)gene of H9N2 avian influenza virus in Jiangsu province.Methods Reverse transcription polymerase chain reaction(RT-PCR)assay was used to detect the nucleic acid of influenza virus A/B and various subtypes from throat swab specimens of patients with acute and severe respiratory infections of unknown cause.Sanger method was used to sequence the vial HA gene of H9N2 positive specimens.N-J phylogenetic tree of HA gene was constructed by using MEGA X software.Results The first laboratory confirmed case of human infection with H9N2 avian influenza virus in Jiangsu province in March 2019 was reported by Suzhou Center for Disease Control and Prevention.Sequence analysis of the HA gene showed that the A/Suzhou/S683/2019(H9N2)strain belonged to Y280-like sub-lineage of the Eurasian lineage,which had 99.23%nucleic acid identity with A/chicken/Shanghai/S1171/2018(H9N2)strain.The amino acid sequence of the HA protein cleavage site is PSRSSR↓GLF,and the key amino acid in receptor binding site shared Q226L mutation.The location of potential glycosylation sites of HA protein of A/Suzhou/S683/2019(H9N2)have changed.Conclusions The H9N2 avian influenza virus obtained from the first case in Jiangsu province has low pathogenicity,but it may have acquired part of the ability to adapt to human hosts.

关 键 词：禽流感 H9N2病毒 血凝素 突变 糖基化位点 

分 类 号：R511.7[医药卫生—内科学]