Changes in EGFR, FOXA2 and MUC5AC expression in respiratory syncytial virus-infected human bronchial epithelium cells and effects of rosiglitazone intervention / 中华微生物学和免疫学杂志

ABSTRACT

Objective To investigate the mechanism of epidermal growth factor receptor-forkhead transcription factor A2 (EGFR-FOXA2) pathway-involved high secretion of mucus in human bronchial epitheli-um (HBE) cells after respiratory syncytial virus (RSV) infection and to evaluate the effects of intervention using agonist ( rosiglitazone ) and antagonist ( GW9662 ) of peroxidase proliferation activated receptor γ( PPARγ) and EGFR inhibitor ( AG1478 ) . Methods HBE cells were randomly divided into six groups A group ( AG1478+RSV) , B group ( rosiglitazone+RSV) , C group ( GW9662+RSV) , D group ( RSV) , E group (0. 1％ dimethyl sulfoxide DMSO) and F group (HBE cell control group). Two hours before RSV infection, A, B and C groups were respectively treated with 10 μmol/L of AG1478, rosiglitazone and GW9662. Expression of EGFR, PPARγ and FOXA2 at mRNA level in each group was detected by real-time fluorescence quantitative RT-PCR 12 h, 24 h and 48 h after HBE cells were infected with or without RSV. Expression of phosphorylated-EGFR ( p-EGFR) and EGFR at protein level was detected by Western blot. ELISA was performed to measure the expression of mucin-5AC (MUC5AC). Results Compared with F group, EGFR expression at mRNA lev-el, p-EGFR/EGFR protein ratio and MUC5AC expression at protein level were increased in a time-dependent manner in A, B, C and D groups at 12 h, 24 h and 48 h. Compared with group F, the expression of PPARγat mRNA level in A, B, and D groups increased at each time point. Moreover, PPARγ expression gradually in-creased over time in A and B groups, reaching the peaks at 48 h, but was in decline in D group. Expression of FOXA2 at mRNA level in RSV-infected HBE cells was declined at each time point compared with that in group F, especially in D group. Compared with group D, A and B groups showed significantly decreased EGFR ex-pression at mRNA level, p-EGFR/EGFR protein ratio and MUC5AC expression at protein level, but markedly increased FOXA2 expression at mRNA level. Conclusions RSV infection increased the expression of MUC5AC at protein level in HBE cells. PPARγand EGFR-FOXA2 signaling pathways were involved in the hypersecretion of airway mucus during RSV infection.