不同年份生产的乙型脑炎减毒活疫苗SA14-14-2基因稳定性研究

Genetic stability of Japanese encephalitis(JE) live-attenuated vaccine SA14-14-2 prepared in different years

为了研究不同年份生产的乙型脑炎减毒活疫苗病毒E蛋白基因稳定性,从分子水平控制乙型脑炎减毒活疫苗质量,确保疫苗安全性,本研究分析了不同年份生产的乙脑活疫苗病毒E蛋白基因核苷酸序列及编码的氨基酸序列,并与该疫苗原始种子、主种子、工作种子、乙脑病毒强、弱毒株进行比较。结果显示不同年份生产的乙脑活疫苗病毒E蛋白基因核苷酸序列与其原始种子、主种子、工作种子和基因库中登录的乙脑病毒弱毒株SA14-14-2的相应序列完全一致,与乙脑病毒强毒株SA14的E蛋白氨基酸序列比较有9个位点氨基酸发生了改变。不同年份生产的乙脑活疫苗病毒E蛋白基因稳定性表明该疫苗质量稳定、安全。

To investigate the genetic stability of Japanese encephalitis （JE） live vaccine SA14-14-2 prepared in different years, the nucleotide and amino acids sequence of various vaccines prepared in different years were analyzed, and compared with those of the primary seed virus, master seed virus, working seed virus of JE live vaccine SA14-14-2 and JE virulent virus strain and attenuated strain recorded in GenBank（ D901941. The nucleotide and amino acids sequence of various lots of JE live vaccine SA14-14-2 prepared in different years were same, and identical with those of their primary, master, working seed viruses and recorded in GenBank, and completely different with those of JE virulent virus SA14. The homolo- gy is 100% in nucleotide and amino acids with JE attenuated virus strain SA14-14-2. The genetic stability of E protein gene of the various lots of JE live vaccine SA14-14-2 prepared in different years demonstrated the consistence and stability of quality of JE live vaccine SA14-14-2. The safety of JE live vaccine SA14-14-2 is guaranteed on molecular level.