湖州市乙型流感病毒HA1基因分析

Analysis of HA1 gene of influenza virus B isolated in Huzhou

目的:了解湖州市乙型流感病毒的基因变异情况和WHO推荐流感疫苗株对湖州市人体的保护情况。方法:采集类流感样本进行流感病毒的分离和鉴定,并对分离到的乙型流感病毒进行核酸的提取,采用逆转录-聚合酶链反应(RT-PCR)扩增病毒基因后进行病毒血凝素HA1。基因核苷酸序列测定,用DNAMAN和MegAlign生物软件对测序结果进行分析处理,并与WHO推荐疫苗株基因进行比对。结果:分离到的毒株为Victoria系的乙型流感病毒,未发现核苷酸的丢失和插入,糖基化位点没有太大改变。毒株HA1区域的核苷酸序列长度为1015 bp,推导的氨基酸序列长度为339个,相比Yamagata系毒株在163位上都多1个天冬酰胺(N)。结论:2010年WHO推荐乙型流感疫苗株与湖州市的流行株为同一谱系毒株,预防保护效果较好。

Objective：To study the variation of hemagglutinin gene HA1 from influenza viruses B and evaluate the protective effect of the vaccine strains recommended by WHO using the virus strains isolated in Huzhou.Methods：Respiratory specimens were collected from the suspected cases of influenza.The influenza viruses were isolated from the specimens and further typed by serological identification.Nucleic acids were extracted from the isolated viruses and the HA1 genes were amplified by reverse transcription polymerase chain reaction（RT-PCR）.The amplicons were sequenced and the data were subjected to the alignment analyses using the softwares of DNAMAN and MegAlign.Results：The influenza virus B isolated in Huzhou was Victoria lineage.The HA1 regions were all 1015 bp with a deduced peptide of 339 amino acids.The viruses had an additional Asparagine（N） on site 163 of HA1 when compared with the viruses of Yamagata lineage.There was no deletion or insertion of nucleotide acid in both lineages and the glycosylation sites were similar.Conclusion：The influenza virus B isolated in Huzhou and the vaccines recommended by WHO in 2010 were Victoria lineage.The protective efect of the vaccines recommended by WHO were effective in Huzhou.