A型流感病毒致病性及跨种间传播的分子生物学基础

MOLECULAR BIOLOGY BASIS OF PATHOGENICITY AND INTERSPECIES TRANSMISSION OF INFLUENZA A VIRUS

A型流感病毒在温血动物中广泛存在,也是目前导致人类和各种动物流感疾病的主型。在自然情况下流感病毒感染的宿主范围有一定的特异性,分离自人的流感病毒一般不能在鸡、鸭等禽类体内复制,同样禽流感病毒在灵长类动物体内的复制能力也极差。但近年来不断发生禽流感病毒(包括H5N1,H9N2,H7N7亚型病毒)直接传染给人的事件,而2009年爆发的人类的H1N1流感的病原则是猪源流感病毒重组而来。研究证实,流感病毒的致病性及跨种间传播的深层原因是病毒分子结构差异及其与宿主细胞相互作用。病毒多种结构蛋白和非结构蛋白某些功能位点上氨基酸的差异是病毒致病性及其跨中传播的分子生物学基础。

Influenza A virus exists in almost all of homothermal animals and is the prime type leading to infection in humans and animals.Under natural circumstances,influenza virus has certain host range.In general,influenza virus of human origin cannot replicate in birds,such as chickens or ducks.Likewise,avian influenza virus has very low replication ability in primates.In the past several years,however,there have been many incidents that avian influenza virus（including H5N1,H9N2 and H7N7 subtypes）have transmitted from avian to human.The pandemics of H1N1 influenza that occurred in 2009 has been confirmed a recombination with influenza virus of swine origin.Studies have demonstrated that the differences in viral molecular structure and the interaction between virus and host cell determine influenza virus pathogenicity and interspecies transmission and the molecular biology basis for such changes are mutations of certain amino acids in functional sites on structural or nonstructural proteins.