中文摘要：

目的探讨在上皮来源的A549细胞上皮-间质转化进程中,IL-33/ST2L信号传导系统的作用及其机制。方法培养A549细胞,RT-PCR检测受体ST2L mRNA;不同浓度白细胞介素-33（IL-33）刺激细胞,在不同时间点以MTT方法检测IL-33对A549细胞增殖的影响;以Real-time PCR法检测不同时间点A549细胞标志性基因E-cad mRNA、α-SMA mRNA以及Vimentin mRNA等的变化和IL-33/ST2L信号通路中关键因子TRAF-6 mRNA的表达改变;Western blot法检测细胞标志性蛋白E-cad、collagenI、Vimentin以及TRAF-6的改变。结果 IL-33对A549细胞的增殖没有影响;不同浓度（5、10及50 ng/mL）IL-33刺激A549细胞24 h,E-cad的表达随浓度的升高逐渐下降、α-SMA的表达随浓度的升高逐渐上调,选择10 ng/mLIL-33作为A549细胞的刺激浓度;随着IL-33刺激时间的逐渐延长,E-cad的表达先降低后升高,α-SMA、Vimentin、collagenI以及TRAF-6的表达呈现先升高后降低的趋势。结论 IL-33/ST2L信号通路的激活能促进A549细胞间质变,尤其是在早期炎症反应阶段作用最为明显。

英文摘要：

[Objective] This experiment was designed to investigate the role and mechanism of IL-33/ST2L signal transduction pathway in the process of epithelium-mesenchyme for A549 cells which in one strain of human alveolar epithelial cells. [Methods] Culturing A549 cells, then the expression of the receptor ST2L was analyzed by RT- PCR; Stimulating A549 cells with rhIL-33 at different time points and different concentration respectively, the prolif- erative rate of A549 cells was tested by MTT; Real-time PCR detected changes of genes E-cad mRNA, α-SMA mRNA, Vimentin mRNA et al and the critical signal transducer TRAF-6 mRNA of IL-33 signal transduction path- way at different time points; The expression of E-cad, collagenI, Vimentin and TRAF-6 was tested by Western blot- ting. [ Results ] The data showed that rhIL-33 can not effect proliferation of A549 cells （P 〉0.05）; After A549 cells was treated for 24 h at different concentration, the expression of E-cad was down-regulated then up-regulated （P 〈 0.05） and the expression of α-SMA was increased gradually （P 〈0.05）, we chosen 10ng/mL as stimulated concentra- tion at following experiments; At different time points （0 h, 6 h, 12 h, 24 h, 48 h,72 h） E-cad reduced then in- creased （P 〈0.05）, α-SMA, Vimentin, eollagenl and TRAF-6 increased and then reduced （P 〈0.05）. [ Conclusions ] The activation of IL-33/ST2L signal transduction pathway can promote A549-mesenchymal transition, especially onearlier inflammatory reaction.