硫酸鱼精蛋白去除Vero细胞乙脑疫苗残余DNA方法的条件优化

Vero细胞规模化生产疫苗时利用硫酸鱼精蛋白可去除乙型脑炎纯化疫苗中Vero细胞的DNA,实验中对不同条件进行了比较。首先在Vero细胞冻融浓缩液中分别按终浓度2mg/ml、1mg/ml、0.5mg/ml、0.2mg/ml、0.1mg/ml加入鱼精蛋白去除DNA,确定0.2~2mg/ml均有良好去除效果;其次将Vero细胞培养的乙脑病毒浓缩液分3组:第1组按2mg/ml、1mg/ml和0.5mg/ml分别沉淀一次、两次;第2组加入终浓度1mg/ml PS后调pH值为pH6.0、6.4、6.8、7.2、7.6;第3组将NaCl浓度调整至0.029mol/L、0.145mol/L、0.725mol/L,加入终浓度1mg/mlPS。确定低浓度多次沉淀、pH值6.8~7.2、盐浓度0.145mol/L条件下沉淀效果最好。

Study on the optimization conditions of the removing residual Vero cell DNA from the JE vaccine with protamine sulfate

It is critical to minimize the residual DNA content in vast production of JE vaccine with Vero cells because of the continued cell line.Various conditions for DNA removal were checked to achieve an optimal one.Firstly,we tried various concentrations of protamine sulfate to remove the DNA from the frozen-thawed Vero cell sample.Secondly,JE vaccine was devided to three groups.The first group was used to test the influence of precipitation times,the second one to examine the influence of pH,and the third one to determine the influence of NaCl concentration.Results showed that 0.2 to 2 mg/ml of PS worked well and the optimum condition for DNA removal with PS was low concentration of vaccine,multiple precipitations,pH6.8-7.2 and 0.145M NaCl.