中国大陆H9N2亚型禽流感病毒HA基因遗传分析及抗原相关性研究

Genetic analysis and antigenic relationship of hemagglutinin genes of H9N2 avian influenza viruses in China's Mainland

为研究我国大陆H9N2亚型禽流感病毒血凝素(HA)基因的分子进化及抗原相关性,本研究对来自15个省、市、自治区的34株H9N2亚型禽流感病毒的HA基因进行了测序及系统发育分析,并采用交叉血凝抑制试验及交叉攻毒保护试验对不同遗传分支下毒株间抗原相关性进行了分析.结果表明,所有34个毒株HA基因均符合低致病性禽流感病毒的特征,但毒株间变异程度增加.系统发育分析表明,我国大陆H9N2亚型禽流感病毒主要分为三个系列,各系列内毒株没有明显的地区及时间特征.抗原相关性研究表明,不同遗传系列下的毒株其抗原相关性明显低于同一系列内部毒株间的抗原相关性,说明我国H9N2亚型禽流感病毒抗原性差异较大.此外,本研究同时筛选得到了用于制备多价苗的代表毒株.

To invesigate the phylogenesis and antigenic relationship of H9N2 avian influenza viruses（AIV） in China's Mainland, hemagglutinin（HA） genes of 34 strains from 15 provinces, cities or autonomous regions are sequenced and analyzed. The antigenic relationship between different strains is also determined by cross- hemagglutination-inhibition test and cross-protection assay. The results show that all 34 isolates belong to low-pathogenic AIV, but increased mutation is observed among strains. Phylogenetic analysis indicates H9N2 AIV from China could be divided into three main genetic series. Antigenic relationship within strains under the same genetic series is significantly higher than strains under different genetic series. These results suggest that there is a significant antigenic variation among H9N2 AIV strains in China's Mainland In addition, three candidate H9N2 strains are recommended for preparation of multivalent vaccine.