胸腺基质淋巴细胞生成素增强正常人支气管上皮细胞屏障功能

Effect of thymic stromal lymphopoietin on human bronchial epithelial permeability

目的探讨胸腺基质淋巴细胞生成素(TSLP)对正常人支气管上皮细胞(16HBE)通透性的影响。方法体外培养16HBE,待细胞状态稳定后,用四唑盐(MTT)比色法检测TSLP(0.1、1、10、100 ng/ml)对16HBE细胞活力的影响。使用无血清1640培养基同步化12 h后,分别加入TSLP刺激液0.1 ng/ml和1ng/ml,分别刺激0、0.5、6、12、24 h,使用跨细胞电阻(TER)及异硫氰酸萤光素-右旋糖酐(FITC-DX)透过率检测不同时间及浓度下的TSLP刺激对16HBE单层细胞通透性的影响。Western blotting法检测TSLP对16HBE粘附连接蛋白E钙粘蛋白(E-cadherin)表达的影响。结果 <1 ng/mlTSLP刺激对16HBE细胞活力无影响,10 ng/mlTSLP可显著促进细胞增殖(P<0.05);浓度为0.1 ng/ml及1 ng/ml的两个TSLP处理组与对照组相比,TER值均显著升高(P<0.001),FITC-DX透过率均明显下降(P<0.05),本效应无明显浓度依赖;E-cadherin表达在0.1 ng/mlTSLP处理组较其余两组明显升高;TSLP处理不同时间后,处理24 h组的TER值及E-cadherin表达量较其余组显著升高(P<0.05),FITC-DX透过率在处理12 h组及24 h组均明显下降(P<0.05),其处理12 h组效果更明显。结论 TSLP可明显改善正常支气管上皮屏障功能。

Objective To investigate the effect of thymic stromal lymphopoietin （TSLP） on the permeablily of monolayer bronchial epithelial cells in vitro. Methods Cultured human bronchial epithelial cell line 16HBE was exposed to 0.1 or 1 ng/ml TSLP for 0, 0.5, 6, 12, or 24 h, and the epithelial monolayer permeability was assessed by measuring transepithelial electrical resistance （TER）, permeability to FITC-labeled dextran （FITC-DX） and expression of E-cadherin. Results Compared with the control cells group, 16HBE cell monolayer showed significantly increased TER （P〈0.001） and decreased FITC-DX fluorescence in the lower chamber （P〈0.05） following exposure to 0.1 and 1 ng/ml TSLP, but these changes were not dose-dependent. Exposure to 0.1 ng/ml TSLP resulted in significantly increased expression of E-cadherin. The 16HBE monolayer exposed to 0.1 ng/ml TSLP for 24 h showed the most obvious increase of TER and E-cadherin expression （P〈0.05）;FITC-DX fluorescence level was markedly decreased after TSLP exposure for 12 h and 24 h （P〈0.05）, and the effect was more obvious in 12 h group. Conclusion TSLP can protect the barrier function of normal bronchial epithelial cells in vitro.