摘要
2020年5月,本实验室在对禽流感常规监测时从广西一鸭场分离到一株H9N8亚型禽流感病毒(AIV),命名为A/duck/Guangxi/S10590/2020(H9N8)(简称DK/GX/S10590/2020)。为了解该H9N8分离株的生物学特性和公共卫生风险,本研究对其进行了全基因组序列及遗传演化分析,并采用贝叶斯端点定年法进行进化分析;进一步以小鼠为动物模型,评价该AIV对哺乳动物的感染性。全基因组序列经BLAST比对,结果显示,该病毒株与H1N1、H3N8、H4N8、H6N1、H7N3、H7N7和H9N2等多种亚型野鸟源低致病性AIV(LPAIV)具有较高同源性,提示其可能是由多种LPAIV在病毒传播过程中经过复杂重配而形成。遗传演化及贝叶斯进化分析结果显示,该病毒可能在2018年末重配产生,后由东亚-澳大利西亚迁徙线上的野鸟引入广西鸭群。特殊氨基酸位点分析结果显示,该病毒HA蛋白裂解位点为PAASNR/GL,仅含有一个碱性氨基酸,且其HA蛋白具有T分子特征,进一步表明该AIV为LPAIV,且具有结合人型唾液酸受体的潜在能力;此外,在内部基因表达蛋白中发现了PB1蛋白的LP、PB1-F2蛋白的LS、PA蛋白的KE和VD、NP蛋白的VM和KQ、以及M1蛋白的HY和AV等多个可增强H9亚型AIV对鸡或哺乳动物组织嗜性的突变,表明该病毒株具有潜在感染鸡和哺乳动物的风险。小鼠感染性试验结果显示,该病毒仅在小鼠鼻甲中低水平复制,对小鼠呈低致病力。本研究为H9亚型AIV的监测和流行病学评估提供了数据支持。
In May 2020, an H9N8 subtype of avian influenza virus(AIV), A/duck/Guangxi/S10590/2020(H9N8)(DK/GX/S10590/2020), was isolated from a duck farm in Guangxi province during our routine surveillance of avian influenza. To understand the biological characteristics and public health risk of this H9N8 isolate, whole-genome sequence analysis, genetic evolution analysis, and Bayesian evolution analysis were performed in this study, and its infectivity to mammals was evaluated in mice as an animal model. A BLAST search of the whole genome sequence revealed that the strain had high homology with H1N1,H3N8, H4N8, H6N1, H7N3, H7N7, H9N2 subtypes of low pathogenic avian influenza virus(LPAIV) from wild birds, suggesting that it may have been formed by complex reassortment of multiple LPAIVs during their transmission. The results of genetic evolution and Bayesian evolutionary analysis indicated that the virus may have been reassorted at the end of 2018 and later introduced into the duck population of Guangxi province by wild birds along the East Asia-Australasian migratory route. Analysis of specific amino acid sites revealed that the virus has the amino acidT in its HA(H3 numbering), indicating its poteintial ability to bind human-type sialic acid receptors;in addition, many mutations, LP in PB1, LS in PB1-F2, KE and VD in PA, VM and KQ in NP, HY and AV in M1, that enhance the tropism in chickens or mammals were identified in its internal gene expression protein, suggesting that this virus is at poteintial risk of infecting chickens and mammals. The results of the mice infectivity test showed that the virus replicated only at low levels in the nasal turbinates of mice and showed low pathogenicity in mice. This study provides data support for surveillance and epidemiological evaluation of H9 subtype AIV.
作者
颜成
崔鹏飞
邢鑫
谷文丽
张元成
衡武昌
王丛丛
邓国华
陈化兰
YAN Cheng;CUI Peng-fei;XING Xin;GU Wen-li;ZHANG Yuan-cheng;HENG Wu-chang;WANG Cong-cong;DENG Guo-hua;CHEN Hua-lan(Influenza Laboratory of the Ministry of Agricultural,State Key Laboratory of Veterinary Biotechnology,Harbin Veterinary Research Institute,Chinese Academy of Agricultural Sciences,Harbin 150069,China)
出处
《中国预防兽医学报》
CAS
CSCD
北大核心
2022年第7期691-696,共6页
Chinese Journal of Preventive Veterinary Medicine
基金
十四五国家重点研发计划(2021YFD1800201)。
关键词
禽流感病毒
H9N8
重配
感染性
avian influenza virus
H9N8
reassortment
infectivity
