河南地区一株鸡源H9N2亚型禽流感病毒的分离鉴定及HA基因变异分析

由发病蛋鸡体内分离得到一株禽流感病毒,经PCR、血凝试验和免疫荧光鉴定为H9N2亚型,命名为A/Chicken/henanxy/2010(H9N2),病毒对SPF鸡无致病性,对其HA基因进行克隆测序,HA基因氨基酸裂解位点为PSRSSRGLF,符合低致病性禽流感的分类标准;并将HA基因和自GenBank读取的H9N2病毒的HA基因序列比较,表明河南分离株属于欧亚分支中的Y280-like分支,与A/Chicken/shandongHL/2010(H9N2)氨基酸同源性94.8%,可能是Y280-like个别核苷酸突变的一株。

Isolation,Identification and Variation Analysis of HA Gene of Chicken H9N2 Subtype Avian Influenza Viruses in Henan

A newly H9N2 isolate,named A/Chicken /henanxy/2010(H9N2),was collected from Hen flock at peak of laying and PCR technique,hemagglutination test and immunofluorescence identified as subtype H9N2. A/Chicken /henanxy/2010(H9N2) was non-pathogenic to SPF chicken. The HA gene sequence of the strains was determined. The sequence analysis of HA gene showed that the amino acid sequence in HA cleavage motif was PSRSSRGLF,which indicated that A/Chicken /henanxy/2010(H9N2) was lentogenic. The HA gene sequences among isolates and the reference strains in GenBank was analyzed by DNAStar software. The results demonstrated that A/Chicken /henanxy/2010(H9N2) belonged to Y280-like sublineage and the homology of amino acid for HA gene is 94.8% between the isolate A/Chicken /henanxy/2010(H9N2) and Y280-like sublineage. The conclusion can be referred for the genetic evolution of AIV H9N2 HA genes,to reveal the epidemic characteristics of the H9N2 in Henan region.