【摘要】 采用常规的血清学试验和特异性RT-PCR方法对华东地区家养水禽中流感病毒的带毒状况进行4年多的监测,分离鉴定出多株H4亚型禽流感病毒。对其中的A/Duck/Yangzhou/216/2002(简称Dk/YZ/216/02)、A/Duck/Yangzhou/526/2003(简称Dk/YZ/526/03)、A/Duck/Yangzhou/36/2004(简称Dk/YZ/36/04)的血凝素基因和Dk/YZ/526/03、Dk/YZ/36/04的神经氨酸酶基因进行了克隆测序,并与GenBank中收录的其它序列进行了比较,遗传进化结果表明Dk/YZ/216/02的血凝素基因(HA)与毒株Tk/Minnesota/833/80(H4N2)同源性最高,而Dk/YZ/526/03和Dk/YZ/36/04的血凝素基因(HA)均与Budgerigar/Hokkaido/1/77(H4N6)同源性最高;而神经氨酸酶基因(NA)遗传进化分析结果表明Dk/YZ/36/04(H4N6)的NA基因与毒株Pigeon/Nanchang/8-142/2000(H3N6)同源性最高,而Dk/YZ/526/03(H4N2)的NA基因与Dk/Hokkaido/13/00(H9N2)同源性最高,3株禽流感病毒的HA推导的氨基酸剪切位点序列均为P-E-K-A-S-R,为典型低致病性禽流感病毒的特征序列,与对SPF鸡的致病力试验相吻合。更多还原

【Abstract】 Several H4 subtype avian A influenza viruses were isolated from waterfowls in some live bird markets when we surveying the ecology of the influenza in East China for more than four years and identified by specific RT-PCR.In this paper,the hemagglutinin(HA) gene and neuraminidase(NA) gene of three representative virus named A/Duck/Yangzhou/216/2002(Dk/YZ/216/02),A/Duck/Yangzhou/526/2003(Dk/YZ/526/03)and A/Duck/Yangzhou/36/2004(Dk/YZ/36/04) had been sequenced and their pathogenicity to SPF chickens had been determined.The results showed that the HA nucleotide sequence of Dk/YZ/216/02 have high identity with Tk/Minnesota/833/80(H4N2),that of Dk/YZ/526/03 and Dk/YZ/Z36/04 have high identity with Budgerigar/Hokkaido/1/77(H4N6);Phylogenetic analysis of the N6 NA genes revealed that the NA gene of Dk/YZ/Z36/04 had genetically close relationships with that of H4N6 viruses isolated from pigeon in jiangxi China,the NA gene of Dk/YZ/526/03 had genetically close relationships with that of H9N2 viruses isolated from duck in Hokkaido.The sequences of cleavage site between HA1 and HA2 consist of P-E-K-A-S-R in all three AIVs,coincide with that of identical low pathogenic AIV,and none of the chickens inoculated with the three AIVs displayed any obvious signs of clinical disease.更多还原