禽源H3N2流感病毒NA基因G170R突变对奥司他韦耐药性的分析

Analysis of the resistance of a G170R mutation in the NA gene of avian H3N2 influenza virus to oseltamivir

目的探讨H3N2小鼠适应株NA基因G170R突变,对奥司他韦是否具有耐药性。方法在小鼠鼻内接种病毒前后分别给小鼠灌胃奥司他韦,分为预防治疗组,治疗组,病毒感染对照组,空白对照组。观察小鼠体重变化情况及死亡情况,每三日各组取肺组织,测定肺组织病毒滴度。结果预防治疗组和治疗组的小鼠在鼻内接种病毒后体重都有所下降,但在感染后期小鼠体重都升高并且无死亡;病毒感染对照组小鼠在鼻内接种病毒后体重迅速下降,直至第8 d小鼠全部死亡。病毒感染对照组小鼠肺病毒滴度比预防治疗组和治疗组小鼠肺病毒滴度高,且到实验第8 d,病毒感染对照组小鼠全部死亡,而预防治疗组小鼠和治疗组小鼠肺病毒滴度都在检测值以下。结论 NA基因G170R突变的H3N2小鼠适应株对奥司他韦暂无耐药作用。

Objective To investigate whether a mouse-adapted strain of H3 N2 with the G170 R mutation in the NA gene is resistant to oseltamivir.Methods Oseltamivir was administered to mice before and after intranasal inoculation,and the mice were divided into a prophylaxis group,a treatment group,a viral infection control group,and a blank control group.Changes in body weight and the death of mice were observed.Lung tissues were taken from each group every three days to measure the viral titer in lung tissues.Results Mice in the prophylaxis group and the treatment group lost weight after intranasal inoculation with the virus,but both groups gained weight and did not die after infection.Mice in the control group that were infected with the virus lost weight rapidly after intranasal inoculation until all mice died on day 8.The pulmonary virus titer in mice in the control group was higher than that in the prophylaxis group and the treatment group,and by day 8 of the experiment all of the mice in the control group infected with the virus died,while the pulmonary virus titer in mice in the prophylaxis group and the treatment group was lower than the detection limit.Conclusion Mouse-adapted H3 N2 with a G170 R mutation in the NA gene was not resistant to oseltamivir.