目的  建立并验证麻疹、腮腺炎、风疹和水痘（measles，mumps，rubella and varicella，MMRV）联合减毒活疫苗中水痘病毒滴度的测定方法。方法 首先通过比较温度，确定中和条件；再根据抗麻疹、腮腺炎、风疹病毒血清对相应病毒的完全中和能力，确定每种抗血清的使用浓度。观察抗血清对2BS细胞生长的影响和对水痘病毒的干扰作用。采用t检验对结果进行比较。结果  与37 ℃ 1 h 相比，4 ℃ 1 h的中和条件能准确反映MMRV疫苗中水痘病毒的滴度水平（t=6.7082，P<0.01）。3种抗血清（麻疹1:80、腮腺炎1:40、风疹1:40）混合后对2BS细胞生长无影响，对不同滴度水痘病毒无干扰（高滴度t=0.4472，P>0.05；中滴度t=0.9045，P>0.05；低滴度t=0.3536，P>0.05）。使用建立的方法测定MMRV疫苗中水痘病毒滴度，实测值与理论值之间的差异无统计学意义（t=1.7533，P>0.05）。结论  建立了MMRV联合减毒活疫苗中水痘病毒滴度的测定方法。

Objective  To establish and verify a titration method of varicella virus in live attenuated measles, mumps, rubella and varicella (MMRV) combined vaccine.   Methods   The neutralization condition was determined by temperature comparison and the appropriate concentration of anti-sera against measles, mumps, and rubella viruses was adopted according to the neutralization ability of each anti-serum to the corresponding virus. The influence on 2BS cell growth and interference with varicella virus by anti-sera were observed. The results were compared by t-test.  Results   Compared with 37 ℃ 1 h, the neutralization condition of 4 ℃ 1 h reflected accurately the titer of varicella virus in MMRV vaccine（t=6.7082, P<0.01）. Three kinds of anti-sera (measles 1:80, mumps 1:40, rubella 1:40) had no influence on 2BS cells. No interference of anti-sera with different titer varicella viruses was observed (high titer t=0.4472, P>0.05; middle titer t=0.9045, P>0.05; low titer t=0.3536, P>0.05). There was no significant difference between the measured and theoretical titer of varicella virus (t=1.7533, P>0.05).   Conclusion    The method for determining varicella virus in MMRV vaccine is established.