1株H3N2亚型猪流感病毒的分离鉴定、基因序列分析及其致病性评价  

Isolation,identification,gene sequence analysis and pathogenicity of H3N2 subtype swine influenza virus

作　　者：陈超阳[1,2] 张颖雪 徐聪聪 施元杰 曹龙 闫喜军 唐丽杰 CHEN Chaoyang;ZHANG Yingxue;XU Congcong;SHI Yuanjie;CAO Long;YAN Xijun;TANG Lijie(College of Veterinary Medicines,Northeast Agricultural University,Harbin 150030,China;Sinovet(Jiangsu)Biopharmaceuticals Co.,Ltd.,Taizhou,Jiangsu 225300,China)

机构地区：[1]东北农业大学动物医学学院,黑龙江哈尔滨150030 [2]华威特(江苏)生物制药有限公司,江苏泰州225300

出　　处：《中国兽医学报》2024年第9期1841-1847,共7页Chinese Journal of Veterinary Science

基　　金：江苏省农业科技自主创新资金资助项目(CX(22)2018)。

摘　　要：采集猪流感(swine influenza, SI)疑似病猪的鼻拭子样品,经RT-qPCR检测H3亚型猪流感病毒(swine influenza virus, SIV),将阳性样品接种SPF鸡胚进行病毒分离,对分离到的H3N2亚型SIV进行全基因组测序及序列分析,并对其致病性进行研究。结果表明,成功分离到1株SIV,经分型RT-PCR鉴定为H3N2亚型,命名为A/Swine/YunNan/KM/06/2023(H3N2),简称SIV H3N2 KM株。全基因组序列BLSAT比对结果显示,SIV H3N2 KM株的8个节段分别与8个不同毒株的猪源或人源流感病毒的同源性最高,分别为95.41%~97.49%,其中HA和NA节段来源于H3N2亚型SIV,NP节段来源于H1N1亚型人流感病毒,M节段来源于H1N2亚型SIV,其他节段均来源于H1N1亚型SIV。HA蛋白的关键受体位点(190D、223V、226I、228S)未发生改变。致病性试验结果显示,感染组仔猪出现体温升高、喷嚏、流鼻涕等症状,可通过鼻腔向外界排毒,剖检后肺脏产生不同程度的肉样实变,免疫组化结果显示,病毒可在肺脏中大量复制。综上,本试验成功分离到1株H3N2亚型SIV,并对该病毒的基因遗传演化、分子特征和致病性进行了研究,揭示了H3N2亚型SIV在不断地发生演变,分离株对仔猪具有致病力,为我国SIV流行情况的监测和SI防控提供了参考依据,并为SI疫苗研发提供了候选毒株。The nasal swab samples of swine influenza(SI)suspected pigs were collected and tested for H3 subtype swine influenza virus(SIV)positive by RT-qPCR,The positive samples were inoculated into SPF chicken embryos for virus isolation.The full genome sequencing and sequence analysis of the isolated H3N2 subtype SIV were conducted,and its pathogenicity was studied.The results showed that a strain of SIV was successfully isolated and identified as H3N2 subtype by RTPCR,named A/Swine/Yunnan/KM/06/2023(H3N2).The BLSAT results showed that the eight segments of SIV H3N2 KM had the highest homology with eight different strains of swine influenza or human influenza viruses,reaching 95.41%-97.49%.The HA and NA segments were derived from H3N2 subtype SIV,the NP segment was derived from H1N1 subtype human influenza virus,the M segment was derived from H1N2 subtype SIV,and all other segments were derived from H1N1 subtype SIV.The key receptor sites(190D,223V,226I,228S)of HA protein remained unchanged.The pathogenicity experiment results showed that infected piglets exhibited symptoms such as fever,sneezing,runny nose,the virus could be detoxified to the outside through the nasal cavity,and the lungs had different degrees of lesion.Immunohistochemistry(IHC)showed that the virus could replicate in the lungs.In conclusion,a strain of H3N2 subtype SIV was successfully isolated,and the genetic evolution,molecular characteristics and pathogenicity of the virus were studied.It revealed that H3N2 subtype SIV is constantly evolving and had pathogenicity to piglets,providing a reference for monitoring and preventing SIV epidemics in China,and provided a candidate strain for SI vaccine development.

关 键 词：猪流感病毒 H3N2亚型 分离鉴定 序列分析 致病性 

分 类 号：S852.65[农业科学—基础兽医学]