呼吸道合胞病毒感染对气道上皮细胞表皮生长因子受体、紧密连接相关蛋白及黏蛋白表达的影响

Effects of respiratory syncytial virus infection on epidermal growth factor receptor, tight junction association proteins and mucin in airway epithelial cells

摘要:

目的 探讨呼吸道合胞病毒（RSV）感染气道上皮细胞后对表皮生长因子受体（EGFR）、紧密连接相关蛋白occludin及E-cadherin、黏蛋白MUC5AC表达的影响，并探讨可能的机制。方法 体外实验分两组，以人气道黏液上皮细胞NCI-H292细胞为研究对象，紫外线下灭活的RSV加入NCI-H292细胞培养基中作为对照组，迅速解冻的RSV感染NCI-H292细胞为RSV感染组。48 h后通过Western blot法检测occludin、E-cadherin、磷酸化EGFR（p-EGFR）及EGFR的蛋白表达水平；采用细胞免疫荧光技术观察两组细胞occludin、E-cadherin的分布及表达；采用RT-PCR法检测两组MUC5AC mRNA的表达。结果 RSV感染组occludin、E-cadherin的蛋白表达水平较对照组下降（P < 0.05）。RSV感染组p-EGFR及EGFR蛋白的表达水平较对照组升高（P < 0.05）。RSV感染组MUC5AC mRNA表达水平较对照组增加（P < 0.05）。结论 RSV可破坏气道上皮细胞间的紧密连接，促进黏蛋白的分泌，影响气道的屏障功能。EGFR的磷酸化在上述过程中起重要作用。

Abstract:

Objective To study the effects of respiratory syncytial virus (RSV) infection on epidermal growth factor receptor (EGFR), tight junction association proteins and mucin in the human airway epithelial cells. Methods Human airway epithelial cells NCI-H292 were randomly treated by ultraviolet light-inactivated RSV (control group) or thawed RSV (RSV infection group). After 48 hours of treatment, the protein levels of occludin, E-cadherin, phosphorylated EGFR and EGFR in NCI-H292 cells were measured by Western blot. The distribution and expression levels of occludin and E-cadherin in NCI-H292 cells were examined by immunofluorescence technique. The expression levels of MUC5AC mRNA in NCI-H292 cells were assessed by RT-PCR. Results The protein levels of occludin and E-cadherin were signifcantly reduced in the RSV infection group compared with the control group (P < 0.05). The protein levels of phosphorylated EGFR and EGFR increased signifcantly in the RSV infection group compared with the control group (P < 0.05). The MUC5AC mRNA levels also increased signifcantly in the RSV infection group compared with the control group (P < 0.05). Conclusions RSV may down-regulate the tight junction association proteins and upregulate the expression of MUC5AC in airway epithelial cells, which contributes to epithelial barrier dysfunction. EGFR phosphorylation may play an important role in regulation of airway barrier.