3株H9亚型禽流感毒株的分离鉴定和交叉攻毒保护试验比较

Isolation and Identification of Three H9 Subtype Avian Influenza Virus and Cross-immunity Protection Comparison

关键词:  H9N2亚型禽流感病毒  HA基因  NA基因  遗传进化分析  交叉攻毒保护

Key words:  H9N2 subtype avian influenza virus  HA gene  NA gene  genetic evolution analysis  cross challenged test

摘要:

为了解山东部分地区H9亚型禽流感病毒变异情况，将2015年采自潍坊、聊城、烟台的H9N2禽流感疑似病料，进行RT-PCR扩增、测序、遗传进化分析， 并将3株分离株纯化后进行了血清学和交叉攻毒保护试验。结果显示： 3株分离株之间的HA和NA基因同源性很高，分别为97%~97.6%和93.5%~94.4%，而与早期分离株和疫苗株的同源性较低，分别为74.9%~90.3%和86.3%~92.3%；遗传进化分析显示3株分离株与Genbank中近年的H9N2分离株亲缘关系近，同属Y280-like分支，而与早期分离株的亲缘关系较远。交叉攻毒保护实验结果证明，不同地点分离的H9N2 禽流感流行毒株间有较好的交叉保护力。本研究为指导禽流感疫情防控以及疫苗研制提供了依据。

Abstract:

To explore the genetic mutations of H9 subtype avian influenza virus in Shandong province, tissues suspected of being infected with AIV H9 subtype from Weifang, Liaocheng and Yantai were collected in 2015. They were detected by RT-PCR method. After sequencing, genetic evolution was analyzed and cross-immunity protection was carried out. The results show that the isolates have high homologies with H9N2 strains of recent years up to 97%~97.6% and 93.5%~94.4% respectively, while shared low homologies with H9N2 strains of early years and vaccine strains, 74.9%~90.3 and 86.3%~92.3% respectively. Genetic evolution analysis results show that the three strains belonged to genetic Y280-like sublineage. There was a good cross protection force among the three H9 subtype isolates from different places. This study has provided guidance for the avain influenza epidemic prevention and control, and also a basis for the research and development of vaccine.