RT Journal Article
SR Electronic
T1 Transforming growth factor-β type II receptor in pulmonary arteries of patients with very severe COPD
JF European Respiratory Journal
JO Eur Respir J
FD European Respiratory Society
SP 556
OP 562
DO 10.1183/09031936.06.00077105
VO 28
IS 3
A1 B. Beghe
A1 E. Bazzan
A1 S. Baraldo
A1 F. Calabrese
A1 F. Rea
A1 M. Loy
A1 P. Maestrelli
A1 R. Zuin
A1 L. M. Fabbri
A1 M. Saetta
YR 2006
UL http://erj.ersjournals.com/content/28/3/556.abstract
AB A mild-to-moderate increase in pulmonary arterial pressure is often associated with severe chronic obstructive pulmonary disease (COPD). Transforming growth factor (TGF)-β is a cytokine involved in the maintenance of integrity of vasculature. The aim of the study was to investigate whether the TGF-β pathway might be involved in the development of pulmonary hypertension associated with COPD. Surgical specimens from 14 patients undergoing lung transplantation for very severe COPD (forced expiratory volume in one second 17±2% of the predicted value) and from seven donors were examined. The expression of TGF-β1 and TGF-β type II receptor (TGF-βRII), cell proliferation index and structural changes in pulmonary arteries were quantified immunohistochemically. In severe COPD patients, increased expression of TGF-βRII was observed in both the tunica media and intima, which was associated with a normal proliferation index in both layers. Conversely, significant thickening of the tunica intima, which was not present in the tunica media, was observed, suggesting that mechanisms other than cell proliferation may be involved in intimal thickening. In conclusion, in the pulmonary arteries of patients with severe chronic obstructive pulmonary disease, there is upregulation of transforming growth factor-β type II receptor expression associated with a normal proliferation index. These findings suggest the activation of an antiproliferative pathway, which might explain the relatively low degree of pulmonary hypertension observed in these subjects.