Folia Histochemica et Cytobiologica (Apr 2010)
Concentrations of plasminogen activator inhibitor-1 (PAI-1) and urokinase plasminogen activator (uPA) in induced sputum of asthma patients after allergen challenge
Abstract
Urokinase plasminogen activator (uPA) and its inhibitor (PAI-1) are involved in tiisue remodeling and repairprocesses associated with acute and chronic inflammation. The aim of the study was to evaluate the effect of allergen challengeon concentration of uPA and PAI-1 in induced sputum of house dust mite allergic asthmatics (HDM-AAs). ThirtyHDM-AAs and ten healthy persons (HCs)were recruited for the study. In 24 HDM-AAs bronchial challenge with Dermatophagoidespteronyssinus (Dp) and in 6 HDM-AAs sham challenege with saline were performed. In HDM-AAs sputumwas induced 24 hours before (T0) and 24 hours (T24) after the challenge. Concentration of uPA and PAI-1 in induced sputumwere determined using immunoenzymatic assays. At T0 in HDM-AAs mean sputum uPA (151±96 pg/ml) and PAI-1(4341±1262 pg/ml) concentrations were higher than in HC (18.8±6.7 pg/ml; p=0.0002 and 596±180 pg/ml; p<0.0001; foruPA and PAI-1 respectively). After allergen challenge further increase in sputum uPA (187±144 pg/ml; p=0.03) and PAI-1(6252±2323 pg/ml; p<0.0001) concentrations were observed. Moreover, in Dp challenged, but not in saline challengedHDM-AAs the mean uPA/PAI-1 ratio decreased significantly at T24. No significant increase in the studied parameters werefound in sham challenged patients. In HDM-AAs allergen exposure leads to activation of the plasmin system in the airways.Greater increase of the PAI-1 concentration than uPA concentration after allergen challenge may promote airway remodelingand play an important role in the development of bronchial hyperreactivity.
