蔗糖垫超速离心法提纯乙型脑炎疫苗

经Vero细胞培养的P3株乙脑灭活病毒，以超滤浓缩和硫酸色精蛋白处理后，40％蔗糖垫层在27500r／min离心6小时，收集沉淀制成提纯乙脑疫苗。其蛋白含量在0．012～0.035mg／ml，稀释8倍后其疫苗效价仍能超过日本提纯鼠脑乙脑疫苗参考标准和我国乙脑疫苗参考标准。Vero细胞残余DNA＜100pg／0．5ml，残余牛血清＜1μg／ml。

Purification of Japanese Encephalitis Vaccine by Ultracentrifugation with Sucrose Bed

The strain P3 of inactivated Japanese encephalitis virus cultured in Vero cells was concentrated by ultrafiltration and treated by protamine sulfate, then ultracentrifuged with 40%sucrose bed at 27500rpm for 6 hours. The precipitate was collected and used for the preparation of JE vaccine. The protien content of the JE vaccine was 0.012~0. 035 mg/ml, and the vaccine titer after 8-folds dilution was stiIl higher than that of the reference standards of Japanese and Chinese JE vaccines. The residual DNA and calf serum in vaccine were <100pg/0. 5ml and <1μg/ml, respectively.