禽流感病毒的致病性和宿主范围:分子决定因素和病毒学观点
Toshihiro Ito1,2,3
1Avian Zoonosis Research Center, Faculty of Agriculture, Tottori University, Tottori, Japan.
The Journal of veterinary medical science
|September 17, 2025
概括
禽流感病毒 (AIV) 的致病性和宿主特异性是由血凝素 (HA) 蛋白决定的. 良性水禽AIVs可以在家禽中变得高度致病,HA受体结合会影响动物感染潜力.
科学领域:
- 病毒学 病毒学
- 分子生物学分子生物学
- 免疫学 免疫学 免疫学
背景情况:
- 禽流感病毒 (AIV) 的致病性主要是由血凝素 (HA) 糖蛋白决定的.
- 高致病性AIV具有高度分裂的HA,导致全身感染,而低致病性菌株需要特定的蛋白酶来激活,导致局部感染.
- 艾滋病毒的宿主特异性也由HA决定,酸受体结合的差异 (艾滋病毒的SAα2,3Gal,人类流感病毒的SAα2,6Gal) 限制了跨物种传播.
研究的目的:
- 调查低致病性禽流感病毒获得高致病性的潜力.
- 了解AIV宿主特异性和流行病菌株的出现背后的分子机制.
主要方法:
- 在家禽中,低致病性水禽AIV分离物的连续传输.
- 分析HA切割部位图案的变化.
- 检查HA受体结合特异性的检查.
主要成果:
- 从低致病性前体生成高度致病性的AIV变体.
- 增加的致病性和转向高度致病性的HA裂部位动机之间的相关性.
- 证明AIV HA优先结合SAα2,3Gal受体,而人类流感病毒更喜欢SAα2,6Gal受体.
结论:
- 良性水禽AIVs可以在家禽中演变为高度致病性变体,构成重大威胁.
- 在HA受体结合特异性的差异对于AIV宿主限制和动物传播的潜力至关重要.
- 猪表达了这两种受体类型,作为流感病毒重新分类的关键"混合容器",促进了新型流行病菌株的出现.
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