VEGF levels in asthmatic airways do not correlate with plasma extravasation.

Abstract

Vascular permeability/vascular endothelial growth factor (VEGF) is a multifunctional cytokine which plays a role in chronic inflammation and angiogenesis. Its expression in bronchoalveolar lavage (BAL) has not been determined although VEGF may be relevant to the pathophysiology of asthma in which oedema is an important feature. We studied VEGF, albumin and IgA immunoreactive levels in the BAL fluids obtained from 27 chronic stable asthmatics, nine untreated chronic bronchitis patients and 15 control subjects. BAL fluid levels of VEGF and VEGF normalized to IgA were not significantly different in any patient group. Both asthmatic steroid- and non-steroid-treated groups had significantly lower albumin levels in their BAL fluids explaining most of the 179% increased VEGF normalized to albumin ratios in non-steroid treated asthmatics. Moreover, VEGF and albumin markers correlated in control subjects (r = 0.73, P = 0.006) and in chronic bronchitics (r = 0.75, P = 0.03, Spearman test), but not in asthmatics. VEGF was inversely correlated with asthma severity (GINA/NHLBI scores) in non-steroid treated asthmatics (tau = - 0.52, P = 0.009, Kendall test). Thus, the potential role of VEGF in asthma requires further studies on bronchial biopsies and induced sputum.