RNAi技术对改善小鼠呼吸道合胞病毒感染后气道炎症的研究

siRNA targeting RSV-M2 gene improved the level of IFN-γ, IL-12 and IL-10 in BALF in mice infected with respiratory syncytial virus

目的探讨小鼠呼吸道合胞病毒（respiratory syncytial virus，RSV）感染后气道的炎症反应以及采用小分子RNA技术（smallinterferenceRNA，siRNA）治疗对气道炎症的改善作用。方法采用针对RSV-M2基因的特异性siRNA滴鼻治疗RSV感染的hALB／c鼠，通过显微镜观察支气管肺泡灌洗液（BALF）白细胞计数及ELASA方法检测BALF中细胞因子IFN-γ、IL-12和IL-10水平的变化情况。结果RSV感染后，BALF白细胞总数显著增加，分类以淋巴细胞为主；细胞因子IFN-γ、IL-12和IL-10水平升高；siRNA治疗后，白细胞总数、淋巴细胞、百分数随着siRNA浓度的增加而下降。IFN-γ、IL-12和IL-10水平随着siRNA浓度的增加而下降，与对照组比较差异有统计学意义（P〈0．05）。结论RSV感染小鼠后，气道发生炎症反应；siRNA技术能够减轻RSV感染后的气道炎症反应。

Objective To elucidate the airway inflammation status in mice infected with respirato- ry syncytial virus （RSV）, and whether the inflammation could be alleviated by small interference RNA （siRNA） targeting specific RSV gene. Methods BALB/c mice were infected with RSV via intranasal in- stillation of RSV suspension, and were then treated with specific siRNA targeting RSV-M2 gene. ELISA assay was used to detect the levels of IFN-γ, IL-12 and IL-10 and Microscope was used to count white blood ceils in bronchoalveolar lavage fluid（BALF）. Results After RSV infection, a significant increase in leuko- cytes count was observed in BALF. Differential count showed a rise in the percentage of neutrophils, eosino- phil, especially lymphocytes and a reduction of the percentage of monocytes and macrophages（P〈0.05 ）. The levels of IFN-γ, IL-12 and IL-10 were also increased（P〈0.05）. Furthermore, the leukocytes count, the percentage of lymphocytes, neutrophils and eosinophil, and the levels of IFN-γ, IL-12 and IL-10.in BALF were decreased accordingly while the mice were given higher concentrations of siRNA （P〈0.05）. Conclusion RSV caused airway inflammation in BALB/c mice, which may be alleviated by RNAi technology.