Fig. 2

Cigarette smoke mediates corticosteroid resistance and decreases MUC1 expression in human bronchial epithelial cells (HBEC). a Cigarette smoke extract (CSE) decreased the mRNA gene expression of MUC1 in HBEC from healthy subjects. b-e HBECs stimulated with lipopolysaccharide (LPS) and CSE 5% were resistant to the anti-inflammatory effects of dexamethasone on IL-8, GM-CSF and MIP3α release. f Both LPS and CSE induce higher IL-8 release in HBECs from smokers and COPD patients than in cells from healthy subjects. g Dexamethasone shows lesser inhibitory effect on LPS-induced IL-8 release in cells from smokers and COPD patients than in cells from healthy subjects. The results are shown as mean ± SE of n = 4 cell populations from healthy subjects (a-g), smokers (f, g) and COPD (f, g) patients. Gene expression was analyzed by real time PCR using the 2^-ΔCt as described in methods. Two-way ANOVA followed by Bonferroni post-hoc tests. a, b, d and e *P < 0.05 compared with control; #P < 0.05 compared with stimulus. (c) *P < 0.05 compared with CSE+ LPS group. f *P < 0.05 compared with non-smoker group; #P < 0.05 compared with control group; ┴ P < 0.05 compared with smoker group. g *P < 0.05 compared with non-smoker group; #P < 0.05 compared with smoker group