PLTP在香烟诱导HBECs合成IL-8中的作用

Effect of PLTP on CSE-induced IL-8 production in human bronchial epithelial cells

目的:研究磷脂转运蛋白(PLTP)对香烟诱导人支气管上皮细胞(HBECs)合成白介素8(IL-8)的影响。方法:Wistar大鼠连续3 d被动吸烟,收集支气管肺泡灌洗液(BALF),苏木精-伊红(HE)染色,免疫组织化学法(IHC)检测蛋白表达;体外培养HBECs,不同浓度烟草提取物(CSE)刺激;PLTP siRNA干扰后,进行CSE刺激。MTT法检测细胞增殖,同时检测IL-8含量及PLTP表达。结果:烟熏组BALF白细胞计数以及分类计数较对照组均明显升高(P<0.01),IHC显示烟熏组PLTP和IL-8蛋白表达高于对照组;高浓度CSE(2%、4%)抑制HBECs增殖(P<0.001);不同浓度的CSE作用24 h后,IL-8mRNA及蛋白表达量增加,而PLTP蛋白表达量下降,并且IL-8蛋白分泌呈现时间依赖性;PLTP siRNA处理后,IL-8表达量明显升高(P<0.001)。结论:PLTP基因缺失促进香烟诱导HBECs合成IL-8。

Objective： To investigate the effect of PLTP gene on CSE-induced IL-8 production in human bronchial epithelial cell line（ HBECs）. Methods： Wistar rats were exposed to air or cigarette smoke for 6 hours / day on 3 consecutive days,then the lungs were sectioned and examined. The number of total white blood cell and differential white blood cells in BALF were counted. The different concentrations of CSE co-cultured with HBECs for 24 hours. Cells growth was detected by MTT assay. Expression levels of PLTP mRNA and IL-8 mRNA were examined by RT-PCR,protein of PLTP was investigated by Western blot,and production of IL-8 examined by ELISA. Results： The number of white blood cells in BALF was significantly increased compared with controls. Enhanced expression level of PLTP and IL-8 were observed in CS-exposure group. Proliferation of HBECs tends to decrease at high concentrations of CSE（ 2. 0% CSE and 4. 0% CSE）. The results suggested that the production of IL-8 induced by CSE in a time-and concentration-dependent manner,while the expression of PLTP induced by CSE in a dose-dependent manner. Furthermore,expression levels of IL-8 significantly increased after silence PLTP gene. Conclusion： PLTP siRNA could increase CSE-induced IL-8 production in HBECs.