摘要
目的：了解浙江省近几年乙型流感病毒的基因变异情况和WHO推荐流感疫苗株对浙江省人体的保护情况。方法：采集浙江省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BioEdit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Yamagata系和Victoria系两个进化系的乙型流感病毒，两系毒株均未发现核苷酸的丢失和插入，糖基化位点没有太大改变。毒株之间核苷酸的同源性为95.25%，氨基酸的同源性为95.28%。Yamagata系毒株HA1区域核苷酸序列长度为1038 bp，推导的氨基酸序列长度为346个，氨基酸变异替换数在6-8之间；Victoria系毒株HA1区域的核苷酸序列长度为1041 bp，推导的氨基酸序列长度为347个，氨基酸变异替换数在2-8之间，相比Yamagata系毒株在163位上都多1个天冬酰胺（N）。基因进化树上可见明显的Yamagata系和Victoria系两个分支。结论：浙江省人群交替流行着Yamagata系和Victoria系两个抗原性不同的进化系的乙型流感病毒，病毒的基因发生了变异，抗原已发生漂移。2001、2006两年WHO推荐乙型流感疫苗株与我省当年流行株为不同谱系毒株，预防保护效果不够理想，其余年份为同一谱系毒株，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 Zhejiang Province since 1999. Methods：Respiratory specimens were collected from the suspected cases of influenza in Zhejiang Province. 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 BioEdit. Results：The viruses of Yamagata lineage and Victoria lineage were isolated. The homology of nucleotide acids was 95. 25% among all the isolated virus strains and their homology of amino acids was 95.28%. The HA1 regions from Yamagata lineage were all 1038 bp in length and therefore with a deduced peptide of 346 amino acids. The amino acid substitutions were between 6 and 8. The HA1 regions from Victoria lineage were all 1041 bp with a deduced peptide of 347 amino acids. The amino acid substitutions were between 2 and 8. All the viruses of Victoria lineage 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 beth lineages and the glycosylation sites were similar. The two branches were distinctively presented in the phylogenetic tree and the strains with same lineage were located in the same branch although they were isolated in different years. The epidemic strains and the Vaccine strains recommended by WHO belonged to the same branch in all years except 2001 and 2006. Conclusion：The antigenic distinctive lineages of Yamagata and Victoria prevailed alternatively in Zhejiang Province in recent years. Variation and antigenic drift were occurred during these years. The protective effect of the vaccines recommended by WHO were poor in 2001 and 2006 due to the different lineage of virus prevailed in Zhejiang Province and the vaccines were effective in all the other years.
出处
《中国卫生检验杂志》
CAS
2008年第3期429-432,共4页
Chinese Journal of Health Laboratory Technology
