1株H1N1亚型猪流感病毒的全基因组特征及其对小鼠的致病性

Genomic and Evolutionary Characterization of a H1N1 Swine Influenza Virus and Its Pathogenicity in Mice

旨在了解河南省猪流感病毒的流行情况及其遗传进化和基因组特征。2018年4月,从河南省某一出现疑似流感症状猪群中采集鼻拭子样品150份用于分离病毒,对分离病毒的全基因组进行序列测定和分析。同时感染6周龄BALB/c小鼠,研究其对小鼠的致病性。结果显示,获得1株H1N1亚型病毒[命名为A/swine/Henan/NY20/2018(H1N1)]。遗传进化表明,其HA和NA基因属于欧亚类禽H1N1分支,PB2、PB1、PA、NP和M基因属于2009甲型H1N1分支,NS基因属于经典H1N1分支。HA蛋白的裂解位点序列为PSIQSR↓GL,具有低致病性流感病毒的分子特征,在小鼠肺和鼻甲有效复制并能引起肺组织病理学变化。本研究分离到1株3源重排H1N1亚型病毒,对小鼠呈现一定致病力,提示应进一步加强对SIV的监测。

This study aimed to understand the epidemiological situation of swine influenza virus(SIV)and analyze its evolutionary and genomic characterization in Henan province.In April 2018,150 nasal swabs were collected from a pig herd with suspected influenza clinical signs to isolate the virus.The isolated virus was sequenced and analyzed.The pathogenicity was evaluated by infecting BALB/c mice.A strain of H1N1 subtype SIV was isolated and named of A/swine/Henan/NY20/2018(H1N1).Phylogenetic analysis results demonstrated that HA and NA genes of the isolated virus belong to the Eurasian avian H1N1 lineage,PB2,PB1,PA,NP and M genes belonged to the pdm/09 H1N1 lineage,and NS gene belonged to the classical swine H1N1 lineage.The HA protein cleavage site of the isolated is PSIQSR↓GL,which accords with the molecular characteristics of low pathogenic avian influenza virus.It can effectively replicate in the lungs and turbinates of mice and can cause pathological changes in lung tissue.A triple reassortant H1N1 subtype virus was isolated in this study,which has a certain pathogenicity to mice,suggesting that further monitoring of SIV should be strengthened.