Li Juan, Gu Min, Liu Dong, Liu Benqi, Jiang Kaijun, Zhong Lei, Liu Kaituo, Sun Wenqi, Hu Jiao, Wang Xiaoquan, Hu Shunlin, Liu Xiaowen, Liu Xiufan
Animal Infectious Disease Laboratory, College of Veterinary Medicine, Yangzhou University, No. 48 East Wenhui Road, Yangzhou, 225009, Jiangsu, China.
Co-innovation Center of Jiangsu for the Prevention and Control of Important Animal Infectious Diseases and Zoonosis, Yangzhou, 225009, Jiangsu, China.
Arch Virol. 2016 Feb;161(2):289-302. doi: 10.1007/s00705-015-2661-2. Epub 2015 Nov 2.
Three H5N8 avian influenza viruses isolated from domestic geese in China in 2014 were characterized phylogenetically and biologically. Phylogenetic analysis of the complete genomic sequences of the three isolates from this study and those of 61 other H5N8 viruses retrieved from the GISAID platform indicated that, chronologically and geographically, all H5N8 viruses of the Asian H5N1 HA lineage of clade 2.3.4.4 are the direct descendents of the K1203 (H5N8)-like viruses first isolated in China in 2010. The three viruses from this study shared high sequence similarity in all eight gene segments with three other isolates from China in 2013, and two Korean isolates were distinct from the recently circulating reassortants causing outbreaks in Asia, Europe and the United States in 2014 and 2015. In vitro viral growth curves indicated that these H5N8 viruses replicated to high titers in CEF, DEF, MDCK and A549 cells but to significantly lower titers in Vero cells. Pathogenicity studies in vivo indicated that these viruses were all highly virulent to chickens and mallard ducks, while they varied from moderate to high virulence in mice. Additionally, hemagglutination assays using α-2,3-sialidase-treated goose red blood cells and solid-phase direct binding assays with different glycans demonstrated that the three viruses could bind to both avian-type SAα-2,3Gal and human-type SAα-2,6Gal receptors. Our findings confirmed the progenitor nature of the K1203-like viruses in generating recent prevalent clade 2.3.4.4 H5N8 reassortants, which have caused tremendous damage to the poultry industry and are a potential threat to public health.
对2014年从中国家鹅中分离出的三株H5N8禽流感病毒进行了系统发育和生物学特性分析。对本研究中的三株分离株以及从GISAID平台获取的其他61株H5N8病毒的完整基因组序列进行系统发育分析表明，在时间和地理上，2.3.4.4分支的亚洲H5N1 HA谱系的所有H5N8病毒都是2010年首次在中国分离出的K1203（H5N8）样病毒的直接后代。本研究中的三株病毒在所有八个基因片段上与2013年中国的另外三株分离株具有高度序列相似性，而两株韩国分离株与2014年和2015年在亚洲、欧洲和美国引起疫情的近期流行重组株不同。体外病毒生长曲线表明，这些H5N8病毒在CEF、DEF、MDCK和A549细胞中复制至高滴度，但在Vero细胞中滴度显著降低。体内致病性研究表明，这些病毒对鸡和野鸭均具有高致病性，而在小鼠中致病性从中度到高度不等。此外，使用α-2,3-唾液酸酶处理的鹅红细胞进行的血凝试验以及与不同聚糖的固相直接结合试验表明，这三株病毒均可与禽型SAα-2,3Gal和人型SAα-2,6Gal受体结合。我们的研究结果证实了K1203样病毒在产生近期流行的2.3.4.4分支H5N8重组株中的祖先性质，这些重组株对家禽业造成了巨大破坏，对公共卫生构成潜在威胁。
