Increased levels of vascular endothelial growth factor in induced sputum in asthmatic patients

Summary Background Vascular endothelial growth factor (VEGF) is highly expressed in the airway of asthmatic patients. As VEGF increases airway vascular permeability, consequent thickening of the airway wall mucosa may lead to narrowing of the airway lumen. Objective We evaluated the relationship between VEGF levels in induced sputum and eosinophilic inflammatory profiles, and the degree of airway vascular permeability in asthmatic patients and we evaluated the effect of inhaled corticosteroids on VEGF levels in induced sputum. Methods Induced sputum specimens were obtained from 28 glucocorticosteroids free asthmatics and 11 healthy control subjects. We examined VEGF levels and airway vascular permeability index in induced sputum. After the initial sputum induction, 21 asthmatics received 8‐week inhaled beclomethasone dipropionate (BDP, 800 µg/day) therapy, then sputum induction was repeated. Results The VEGF levels in asthmatics were significantly higher than in healthy control subjects (P