The Regulated Investigation Of Allergic Airway Inflammation In Asthma Mice By Small Interference RNA Silencing STAT1

Objective:Signal transducer and activator of transcription 1 (STAT1) is the first STAT family members found to participate in IFN (IFN) signal transduction process, it is essential for innate immunity, IFN-γand other cytokines through the JAK-STAT pathway activation of STAT1 and induction of gene expression, the completion of cytokine-mediated signal transduction process, resulting in asthma airway inflammation and hyperresponsivenes. For the gene therapy of inflammatory diseases such as bronchial asthma foundation,we investigated the expression of STAT1 protein in lung tissues of asthma mice,and analyzed the regulation of airway inflammation responses with specific siRNA(small interference RNA) for STAT1.In this study, using specific STAT1 siRNA (small interfering RNA) silencing of bronchial asthma airway epithelial cells, to detect the expression levels of STAT1 in lung tissue and infiltration of inflammatory cells number, investigation the STAT 1-specific siRNA on airway inflammation regulation in asthma mice, for gene therapy of bronchial asthma and other inflammatory diseases basis. Methods:Twenty-four BALB/c mice were randomly divided into PBS group, PG-HK(random arrangement RNAi) group and STAT1 group,all mice were sensitized with OVA/alum suspension twice i.p. (days 1 and 14), and challenged with 100mg/ml OVA solution at days 28-30 by intranasal application. Intranasal application of 100mg/ml STAT1 siRNA to the STAT1 group in days 26-29,another two groups were applicated the equivalent volume PBS liquid or random arrangement siRNA. SPSS13.0 software for experimental data used statistical analysis, univariate analysis of variance and randomized block design analysis of variance, between the number of multiple samples were compared by LSD method, P<0.05 indicated significant difference, and at the same time the number of inflammatory cells in BALF and interferon-γ(IFN-γ), interleukin 4 (IL-4) between the correlation was analyzied. Results:The results show that STAT1 siRNA can reduce the asthma mice airway inflammatory cell infiltration (mainly eosinophils), STAT1 group WBC, eosinophils (EOS) and lymphocytes (LC) number less than the other two groups, There were significant differences between them(P<0.01); Detected by ELISA, the bronchoalveolar lavage fluid of each group, showing that STAT1 group IFN-γhigher than the PBS group and PG-HK group, while IL-4 was lower than the other two groups, comparison between them (P<0.01) Statistically significant;Measured by immunohistochemistry in lung tissue of each group STAT1 protein expression was found significantly reduced in STAT1 group. Conclusion:1. STAT1-specific siRNA can transfected efficiently into asthmatic airway epithelial cells.2. STAT1-specific siRNA can inhibit the STAT1 expression in asthmatic airway epithelial cells.3. Transfected the STAT1-specific siRNA into asthmatic mice can reduce airway inflammation.