Fig. 1

The expression of miR-146a is downregulated in epithelial cells from airway biopsies of patients with asthma. a–c Relative expression of miR-146a in bronchial brushing specimens from patients measured by RT-qPCR. Data represent mean ± SEM. a Unpaired t-test, ***P < 0.001. b Patients were categorized into inflammatory phenotypes based on BALF cell percentages: eosinophilic (E), > 2% of eosinophils and < 3% of neutrophils in BALF; neutrophilic (N), < 2% eosinophils and > 3% neutrophils in BALF; paucigranulocytic (P), < 2% of eosinophils and < 3% neutrophils in BALF). One-way ANOVA, *P < 0.05. c Linear regression analysis between miR-146a expression in asthmatic bronchial brushings (data presented on log2 scale) and neutrophil percentage among non-epithelial BALF cells. 95% confidence interval (CI) of the regression line is shown as dotted line. d, e 10 μm sections of frozen bronchial biopsy samples were subjected to in situ hybridization (d) or hematoxylin and eosin staining (e), bar = 50 μm. d Blue color shows the expression of miR-146a. Black dashed line indicates the outer border of the epithelium layer in the specimen. Red dashed line indicates the outer border of the basal lamina. One asthmatic and non-asthmatic sample representative of 3 and 2 subjects, respectively