TLR4在气道上皮细胞诱导的哮喘气道平滑肌细胞迁移中的作用

Effect of TLR4 on the migration of asthmatic airway smooth muscle cells induced by airway epithelial cells

目的:探讨Toll样受体4(TLR4)的激活在气道上皮细胞诱导的哮喘气道平滑肌细胞(ASMCs)迁移中的作用。方法:细胞消化法培养原代哮喘ASMCs,TNF-α刺激上皮细胞系RTE细胞收集细胞培养上清液,检测上清液中IL-8和RANTES的含量,改良Boyden趋化小室检测哮喘ASMCs的跨膜迁移,以TLR4抗体作为工具药,观察其在上皮细胞诱导的哮喘ASMCs跨膜迁移中的作用。结果:各TNF-α组培养上清液中IL-8和RANTES水平均显著增高,20 ng/ml组较其他组显著增高(P<0.01)。各组哮喘ASMCs跨膜迁移较正常组均增加(P<0.01);哮喘组和TNF-α+TLR4抗体组哮喘ASMCs跨膜迁移数较TNF-α组显著减少(P<0.01)。TLR4抗体组哮喘ASMCs跨膜迁移数较哮喘组增加(P<0.05)。结论:气道上皮细胞可能通过分泌细胞因子激活哮喘ASMCs表面的TLR4,诱导增强ASMCs的跨膜迁移,在哮喘的气道重构中发挥一定的作用。

Objective： To explore the effect of Toll-like receptor 4（TLR4） activation on the migration of asthmatic airway smooth muscle cell（ASMCs） induced by airway epithelial cells.Methods： Primary ASMCs were cultured by the method of cell digestion.Cell culture supernatant of RTE cells were collected by TNF-α stimulation of epithelial cells.Detected the IL-8 and RANTES levels in the supernatant.The transmembrane migration of asthmatic ASMCs were detected by Modified Boyden chemotaxis chamber.The effect of TLR4 on the migration of asthmatic ASMCs induced by epithelial cells with TLR4 antibody drugs as a tool.Results： The levels of IL-8 and RANTES in the supernatant of TNF-α groups were significantly increased,and that in the 20 ng/ml group was significantly higher than other groups（P0.01）.The transmembrane migration of asthmatic ASMCs groups was increased than that of control group.The transmembrane migration of asthmatic ASMCs from asthma group and TNF-α＋TLR4 antibody group was significantly decreased compared with that in TNF-α group（P0.01）.The migration of asthma ASMCs from TNF-a＋TLR4 antibody group was increased than that of asthma group（P0.05）.Conclusion： TLR4 in the surface of asthmatic ASMCs may be activated by cytokines secreted by the airway epithelial cells and enhance the transmembrane migration of asthmatic ASMCs induced by airway epithelial cells so that it plays a role in airway remodeling of asthma.