BACKGROUND: Transforming growth factor-beta1 (TGF-â1) is a multipotential cytokine with angiogenic activity. There are only limited data about its role in airway remodeling in COPD. We have previously shown that the reticular basement membrane (Rbm) is hypervascular in the airways of current smokers either with or without chronic obstructive pulmonary disease (COPD). This study evaluated TGF-â1 immunostaining in the Rbm and its relationship to vascularity in smokers with or without COPD. METHODOLOGY/PRINCIPAL FINDINGS: Bronchial biopsies from 15 smokers with normal lung function, 19 current and 14 ex-smokers with COPD were immunostained for TGF-â1 antibody and compared to 17 healthy controls. The percentage area of tissue and also number and area of vessels staining positively for TGF-â1 were measured and compared between groups. Some bronchial biopsies from current smoking COPD subjects were also stained for phosphorylated (active) Smad2/3. Epithelial TGF- â1 staining was not different between COPD current smokers and normal controls. TGF-â1 stained vessels in the Rbm were increased in smokers with normal lung function, current smoking COPD and ex-smokers with COPD compared to controls [median (range) for number of vessels/mm Rbm 2.5 (0.0-12.7), 3.4 (0.0-8.1) and 1.0 (0.0-6.3) vs. 0.0 (0.0-7.0), p<0.05]. Percentage of vessels stained was also increased in these clinical groups. Preliminary data suggest that in current smoking COPD subjects endothelial cells and cells in the Rbm stain positively for phosphorylated Smad2/3 suggesting TGF-â1 is functionally active in this situation. CONCLUSIONS/SIGNIFICANCE: Vessel-associated TGF-â1 activity is increased in the bronchial Rbm in smokers and especially those with COPD.
History
Publication title
PLoS One
Volume
7
Issue
6
Article number
e39736
Number
e39736
Pagination
1-5
ISSN
1932-6203
Department/School
Tasmanian School of Medicine
Publisher
Public Library of Science
Place of publication
1160 Battery st, San Francisco, CA 94111, USA
Rights statement
Copyright 2012 Soltani et al. Licensed under Creative Commons Attribution License 2.5 Generic (CC BY 2.5) http://creativecommons.org/licenses/by/2.5/