Objective In China, 24 cases of human infection with highly pathogenic avian influenza(HPAI) H5 N6 virus have been confirmed since the first confirmed case in 2014. Therefore, we developed and assessed two H5 N6 candi...Objective In China, 24 cases of human infection with highly pathogenic avian influenza(HPAI) H5 N6 virus have been confirmed since the first confirmed case in 2014. Therefore, we developed and assessed two H5 N6 candidate vaccine viruses(CVVs).Methods In accordance with the World Health Organization(WHO) recommendations, we constructed two reassortant viruses using reverse genetics(RG) technology to match the two different epidemic H5 N6 viruses. We performed complete genome sequencing to determine the genetic stability. We assessed the growth ability of the studied viruses in MDCK cells and conducted a hemagglutination inhibition assay to analyze their antigenicity. Pathogenicity attenuation was also evaluated in vitro and in vivo.Results The results showed that no mutations occurred in hemagglutinin or neuraminidase, and both CVVs retained their original antigenicity. The replication capacity of the two CVVs reached a level similar to that of A/Puerto Rico/8/34 in MDCK cells. The two CVVs showed low pathogenicity in vitro and in vivo, which are in line with the WHO requirements for CVVs.Conclusion We obtained two genetically stable CVVs of HPAI H5N6 with high growth characteristics,which may aid in our preparedness for a potential H5N6 pandemic.展开更多
目的 对长沙市1例人感染禽流感H5N6病毒A/Changsha/1/2022(H5N6)的遗传进化与分子特征进行分析,为防控人感染H5N6禽流感提供依据。方法 运用第三代测序平台对样本进行全基因组测序,从美国国家生物技术信息中心(National Center for Biot...目的 对长沙市1例人感染禽流感H5N6病毒A/Changsha/1/2022(H5N6)的遗传进化与分子特征进行分析,为防控人感染H5N6禽流感提供依据。方法 运用第三代测序平台对样本进行全基因组测序,从美国国家生物技术信息中心(National Center for Biotechnology Information, NCBI)和全球共享禽流感数据倡议组织(Global Initiative on Sharing All Influenza Data, GISAID)数据库下载参考序列进行比对,利用Mega7软件构建遗传进化树并分析关键氨基酸变异位点。结果 对序列进行分析发现,本研究毒株属于H5亚型Clade2.3.4.4b分支。PB1与湖南省A/duck/Hunan/S40199/2021(H5N6)同源性为99.69%;PB2与A/Whooper swan/Sanmenxia/Y36/2020(H5N8)同源性为98.58%;其余序列与2021年广州发现的毒株A/Guangdong/1/2021(H5N6)高度同源。以上结果表明该病例是由重组的H5N6亚型禽流感病毒感染导致。对毒株序列的氨基酸位点分析发现,裂解位点氨基酸组成为RERRRKR↓GLF,符合高致病性禽流感特征。HA序列中Q226L和G228S位点未发生突变,提示病毒保留结合禽类受体的特征,然而S127P、S137A、T160A、T192R、A267T的突变增加了病毒对人类的亲和性。NA蛋白茎部59-70位点缺失,提示该毒株能增强病毒在哺乳动物体内的毒力。内部基因PB1发生S622G突变,PB2发生K389R和V598T突变,PA发生N409S突变,M1发生N30D和T215A突变,NS1发生P42S突变,这些突变会增强禽流感病毒感染小鼠的毒力。结论 本研究的长沙市人感染H5N6病毒为高致病性禽流感病毒,倾向于结合禽类受体,但关键氨基酸位点存在多处变异进而易于感染人类,应持续加强对禽流感H5N6病毒的监测与研究。展开更多
基金This study was supported by the National Major Science and Technology Project for Control and Prevention of Major Infectious Diseases in China[No.2018ZX10711001,2018ZX10305409-004-002]Emergency Prevention and Control Project of Ministry of Science and Technology of China[No.10600100000015001206].
文摘Objective In China, 24 cases of human infection with highly pathogenic avian influenza(HPAI) H5 N6 virus have been confirmed since the first confirmed case in 2014. Therefore, we developed and assessed two H5 N6 candidate vaccine viruses(CVVs).Methods In accordance with the World Health Organization(WHO) recommendations, we constructed two reassortant viruses using reverse genetics(RG) technology to match the two different epidemic H5 N6 viruses. We performed complete genome sequencing to determine the genetic stability. We assessed the growth ability of the studied viruses in MDCK cells and conducted a hemagglutination inhibition assay to analyze their antigenicity. Pathogenicity attenuation was also evaluated in vitro and in vivo.Results The results showed that no mutations occurred in hemagglutinin or neuraminidase, and both CVVs retained their original antigenicity. The replication capacity of the two CVVs reached a level similar to that of A/Puerto Rico/8/34 in MDCK cells. The two CVVs showed low pathogenicity in vitro and in vivo, which are in line with the WHO requirements for CVVs.Conclusion We obtained two genetically stable CVVs of HPAI H5N6 with high growth characteristics,which may aid in our preparedness for a potential H5N6 pandemic.
文摘目的 对长沙市1例人感染禽流感H5N6病毒A/Changsha/1/2022(H5N6)的遗传进化与分子特征进行分析,为防控人感染H5N6禽流感提供依据。方法 运用第三代测序平台对样本进行全基因组测序,从美国国家生物技术信息中心(National Center for Biotechnology Information, NCBI)和全球共享禽流感数据倡议组织(Global Initiative on Sharing All Influenza Data, GISAID)数据库下载参考序列进行比对,利用Mega7软件构建遗传进化树并分析关键氨基酸变异位点。结果 对序列进行分析发现,本研究毒株属于H5亚型Clade2.3.4.4b分支。PB1与湖南省A/duck/Hunan/S40199/2021(H5N6)同源性为99.69%;PB2与A/Whooper swan/Sanmenxia/Y36/2020(H5N8)同源性为98.58%;其余序列与2021年广州发现的毒株A/Guangdong/1/2021(H5N6)高度同源。以上结果表明该病例是由重组的H5N6亚型禽流感病毒感染导致。对毒株序列的氨基酸位点分析发现,裂解位点氨基酸组成为RERRRKR↓GLF,符合高致病性禽流感特征。HA序列中Q226L和G228S位点未发生突变,提示病毒保留结合禽类受体的特征,然而S127P、S137A、T160A、T192R、A267T的突变增加了病毒对人类的亲和性。NA蛋白茎部59-70位点缺失,提示该毒株能增强病毒在哺乳动物体内的毒力。内部基因PB1发生S622G突变,PB2发生K389R和V598T突变,PA发生N409S突变,M1发生N30D和T215A突变,NS1发生P42S突变,这些突变会增强禽流感病毒感染小鼠的毒力。结论 本研究的长沙市人感染H5N6病毒为高致病性禽流感病毒,倾向于结合禽类受体,但关键氨基酸位点存在多处变异进而易于感染人类,应持续加强对禽流感H5N6病毒的监测与研究。
