不同温度培养的3株EV71毒株的增殖动力学分析

目的对不同温度培养的3株EV71中国流行株的增殖动力学进行分析。方法分别在32、35、37和40℃条件下对FY23、K9和S1株EV71进行传代培养、2～24h培养及噬斑培养,采用微量滴定法测定病毒的感染性滴度;传代培养的子代病毒通过脑内注射方式感染新生ICR乳鼠,观察病毒的致病性。结果传代培养时,在32和40℃培养的3株病毒致细胞完全病变时间较35和37℃延长,且子代病毒滴度下降,35℃培养的病毒滴度较37℃升高;3株病毒培养24h后,37℃培养的病毒增殖效率最高,35℃次之,40℃最低;4个温度培养的病毒噬斑形态无明显变化;新生乳鼠脑内注射致死率差异无统计学意义(P>0.05)。结论培养温度的变化可影响EV71的致细胞病变速度及子代病毒的增殖,但对病毒噬斑的形态及新生乳鼠的致病能力无明显影响。

Proliferation Kinetics of Three Enterovirus 71 Strains at Various Temperatures

Objective To analyze the proliferation kinetics of three current epidemic enterovirus 71(EV71)strains in China.Methods EV71 strains FY23,K9 and S1 subjected to subculture,2 ~ 24 h culture and plaque culture at 32,35,37 and 40℃ separately.The infectious titers of EV71 strains were determined by microtitration.The progeny strains were injected i.c.to the newborn ICR suckling mice to observe the pathogenicity.Results The time for complete CPE of three EV71 strains subcultured at 32 and 40℃ were longer than those at 35 and 37℃,while the titers of progeny strains decreased.However,the titers of strains subcultured at 35℃ were higher than those at 37℃.In the order of proliferation rate after culture for 24 h,the strains were those cultured at 37,35 and 40℃.No significant changes were observed in the morphologies of plaques formed by the strains cultured at four temperatures.The mortality rates of newborn suckling mice injected i.c.with the strains cultured at various temperatures showed no significant difference(P > 0.05).Conclusion The change of temperature for culture influenced the time for CPE and the proliferation of progeny of EV71 strains,while showed no significant influence on the morphology of plaque and pathogenicity in animals.