Epithelial mesenchymal interactions in asthmatic children

The alteration of the mesenchymal layer underlying the bronchial epithelium, triggered by epithelial dysfunction, is a topic of emerging interest in asthma. Whether this dysfunction is already present in asthmatic children, and therefore in the early stages of the disease, has been scarcely investigated. We evaluated the degree of epithelial damage, E-cadherin (E-cad) and TGFβ1 expression, and their relation with basement membrane (BM) thickness in asthmatic children. Bronchial biopsies were obtained from 27 children undergoing bronchoscopy for appropriate indications: 16 asthmatics (age2-10yrs) and 11 nonasthmatic controls (4-9yrs). Epithelial damage and BM thickness were quantified by histochemistry and E-cad and TGFβ1 by immunohistochemistry. Asthmatic children had evidence of epithelial damage compared to controls (median;range:52;20-91 vs 33;0-83% p