帕拉米韦对流感病毒感染小鼠免疫功能及炎症反应的调节作用

目的探究帕拉米韦对流感病毒感染小鼠免疫功能及炎症反应的调节作用。方法将48只BALB/c小鼠随机分为对照组、感染组、低、高剂量治疗组,每组12只,病毒感染组、低、高剂量治疗组小鼠用H1N1病毒株(PR8)滴鼻途径攻毒,4 h后治疗组小鼠通过肌肉注射帕拉米韦4、20 mg/kg·d,连续注射5 d,对照组和病毒感染组给予等量生理盐水;在攻毒后3 d时,每组随机取2只小鼠处死,观察肺组织病理变化及其病毒载量;攻毒后5 d时,每组随机取6只小鼠处死,取脾制成单细胞后,利用流式细胞仪检测T淋巴细胞亚群水平,取肺组织制成组织匀浆,利用酶联免疫吸附法(ELISA)检测白细胞介素-2(Interleukin-2,IL-2)、IL-6、肿瘤坏死因子-α(Tumor necrosis factor-α,TNF-α)、干扰素-γ(interferon-γ,IFN-γ)水平,每日观察小鼠状态,持续观察14 d,根据观察结果分析小鼠的存活率及平均生存时间。结果攻毒14 d后,感染组小鼠全部死亡,死亡率明显高于低、高剂量治疗组(P<0.05),低剂量治疗组的死亡率高于高剂量治疗组(P<0.05);攻毒后3 d时,低、高剂量治疗组小鼠的肺指数及肺组织病毒载量低于感染组(P<0.05),高剂量治疗组上述指标变化更显著(P<0.05);感染组小鼠肺组织的病理损伤及炎症浸润严重,低、高剂量治疗组小鼠的病理损伤及炎症浸润有不同程度减轻,且高剂量治疗组改善更明显;攻毒后5 d时,低、高剂量治疗组小鼠的CD₄⁺、CD₄⁺/CD_₈⁺、IL-6、TNF-α水平低于感染组,IL-2、IFN-γ水平高于感染组(P<0.05),且高剂量治疗组的IL-6、TNF-α水平低于低剂量治疗组,IL-2、IFN-γ水平高于低剂量治疗组(P<0.05)。结论帕拉米韦通过抑制肺组织中流感病毒的释放和增殖,缓解过度免疫反应引起的炎症损伤,进而提高小鼠存活率。

Effect of peramivir on regulation of immune function and inflammatory response in mice with influenza virus infection

OBJECTIVE To explore the regulatory effects of paramivir on immune function and inflammatory response in mice with influenza virus infection.METHODS Totally 48 BALB/c mice were randomly divided into the control group,the infection group,the low-dose treatment group and the high-dose treatment group,with 12 mice in each group.The mice in the infection group,the low-dose treatment group and the high-dose treatment group were treated with H1 N1 virus strain(PR8)by nasal route,4 hours later,the mice in the treatment group were injected intramuscularly with 4 and 20 mg/kg·d paramivir for 5 d.The control group and the infection group were given the same volume of normal saline.2 mice were randomly chosen from each group and put to death after the challenge for 3 days so as to observe the pathological changes of lung tissues and viral load;6 mice were randomly chosen from each group and put to death after the challenge for 5 days,the spleen was made into single cells,the levels of T lymphocyte subsets were detected by flow cytometry,the lung tissues were made into tissue homogenate,and the levels of interleukin-2(IL-2),IL-6,tumor necrosis factor-α(TNF-α)and interferon-γ(IFN-γ)were detected by means of enzyme-linked immunosorbent assay(ELISA).The state of the mice was observed everyday for 14 days,and the survival rate and average survival time of the mice were observed based on the result.RESULTS After the challenge for 14 days,all mice in the infection group died,and the mortality rate of the infection group was significantly higher than that of the low-dose group and the high-dose treatment group(P<0.05),the mortality rate of the low-dose treatment group was significantly higher than that of the high-dose treatment group(P<0.05).After the challenge for 3 days,the lung indexes and the viral load of lung tissues were significantly lower in the low-dose treatment group and the high-dose treatment group than in the infection group(P<0.05),the above indexes of the high-dose treatment group changed more significantly(P<0.05).The pathological damage and inflammatory infiltration of lung tissues were severe in the infection group,the pathological damage and inflammatory infiltration of the low-dose treatment group and the high-dose treatment group relieved in varying degree,and the above indexes of the high-dose treatment group were improved more significantly.The levels of CD₄⁺,CD₄⁺/CD₈⁺,IL-6 and TNF-αof the low-dose treatment group and the high-dose treatment group were significantly lower than those of the infection group after the challenge for 5 days,while the levels of IL-2 and IFN-γof the low-dose treatment group and the high-dose treatment group were significantly higher than those of the infection group(P<0.05);the levels of IL-6 and TNF-αof the high-dose treatment group were significantly lower than those of the low-dose treatment group,while the levels of IL-2 and IFN-γof the high-dose treatment group were significantly higher than those of the low-dose treatment group(P<0.05).CONCLUSION Peramivir can relieve inflammatory damage caused by excessive immune response by inhibiting release and proliferation of influenza virus in lung tissues so as to raise the survival rates of mice.