中文摘要：

目的:探讨IL-33/TLR4信号通路在上皮来源的A549细胞上皮-间质转化中的作用。方法:培养A549细胞,用5 ng/mL的转化生长因子β1(TGF-β1)刺激A549细胞;在不同时间点(0,12,24,48 h)MTT法检测TGF-β1对A549细胞增殖的影响;荧光定量PCR方法检测IL-33信号通路中关键因子IL-33,Toll样受体4(TLR4)基因的表达改变;蛋白质印迹法检测α-平滑肌肌动蛋白(α-SMA)、E钙黏蛋白(E-cad)、磷酸化蛋白激酶(p-AKT)的动态表达。结果:TGF-β1刺激A549细胞后,细胞增殖无明显变化(P】0.05),IL-33表达量先升高,后下降(P【0.05);E-钙黏蛋白表达量逐渐下降,α-SMA表达量逐渐升高,TLR4先升高后下降(P【0.05);p-AKT表达量逐渐升高(P【0.05)。结论:IL-33/TLR4信号通路在A549细胞的上皮-间质转化中发挥了重要作用。

英文摘要：

Objective:To investigate the role and mechanism of IL-33 in the process of turning epithelium-mesenchyme for A549 cells which is in one strain of human alveolar epithelial cells.Methods:To stimulate cultured A549 cells with TGF-β1 (5 ng/mL).MTT assay was used to assess the proliferation of the A549 cells in response to TGF-β1 treatment the dynamic expressions of IL-33/TLR4 mRNA were detected by RT-PCR.Western blotting were employed to examine the mRNA and protein expressions of α-smooth muscle actin (α-SMA) and E-cad,p-AKT.Results:The data showed that TGF-β1 had no obvious effects on the proliferation of A549 cells.Stimulated by TGF-β1,E-cad expression of A549 cells gradually declined.α-SMA expression was higher.p-AKT expression gradually increased.Real-time PCR had shown that expressions of IL-33/TLR4 mRNA increased firstly then decreased gradually.The significant differences were observed from 0 h to 24 h,especially on 24 h,compared with control group(P ＜ 0.05).Conclusion:IL-33/TLR4/PI3K/AKT signal transduction pathway promoted epithelial-mesenchymal transition (EMT) of A549,especially on earlier inflammatory reaction.