目的 筛选阳性对照病毒在不同细胞基质中的最适感染复数（multiplicity of infection，MOI）,以优化水痘减毒活疫苗外源病毒因子检查法（细胞培养法）。方法 致细胞病变观察：将水痘-带状疱疹病毒以0.005、0.010、0.020的MOI分别接种至Vero、2BS和MRC-5细胞，培养7 d后观察细胞病变，病变较典型时对应的MOI即为最适MOI。血细胞吸附观察：将牛副流感病毒3型以0.1、0.2、0.4的MOI分别接种至Vero、2BS、MRC-5细胞，培养7 d后分别于2~8 ℃和20~25 ℃放置30 min，观察血细胞吸附，血细胞吸附较典型时对应的MOI即为最适MOI。结果 对Vero、2BS、MRC-5细胞，当水痘-带状疱疹病毒MOI分别为0.020、0.010、0.005时，30%~50%细胞出现典型病变；对Vero、2BS、MRC-5细胞，当牛副流感病毒3型MOI分别为0.1、0.2、0.4时，30%~50%细胞出现典型血细胞吸附。结论 水痘-带状疱疹病毒感染Vero、2BS和MRC-5细胞的最适MOI分别为0.020、0.010、0.005；牛副流感病毒3型感染Vero、2BS和MRC-5细胞的最适MOI分别为0.1、0.2、0.4。

Objective  To screen the optimal multiplicities of infection (MOIs) of positive control viruses in different cell substrates, in order to obtain the best results of exogenous virus factor test (cell culture method) for live attenuated varicella vaccine. Methods  For cytopathic effect (CPE) observation, Vero, 2BS and MRC-5 cells were inoculated with varicella-zoster virus (VZV) at 0.005, 0.010 and 0.020 M0Is, then CPE was observed after 7 d. When the pathological changes were typical, the corresponding MOI was the optimal MOI. For hemadsorption experiment, Vero, 2BS and MRC-5 cells were inoculated with bovine parainfluenza virus 3 (BPIV3) at 0.1, 0.2 and 0.4 MOIs. After 7 d of culture, Vero, 2BS and MRC-5 cells were placed at 2-8 ℃ and 20-25 ℃ for 30 min, respectively, and then observed for hemadsorption. When the hemadsorption was typical, the corresponding MOI was the optimal MOI. Results  At MOI 0.020 for Vero cells, MOI 0.010 for 2BS cells and M0I 0.005 for MRC-5 cells, 30%-50% typical lesions were observed in corresponding cells. At MOI 0.1 for Vero cells, MOI 0.2 for 2BS cells and MOI 0.4 for MRC-5 cells, 30%-50% typical hemadsorption was observed in corresponding cells. Conclusions  The optimal MOI values of VZV in Vero, 2BS and MRC-5 cells infected are 0.020, 0.010 and 0.005, respectively. The optimal MOI values of BPLV3 in Vero, 2BS and MRC-5 cells infected by BPIV3 are 0.1, 0.2 and 0.4, respectively.