Transforming Growth Factor-pi Levels in Induced Sputum Samples of Asthmatic Subjects

The histopathology of bronchial asthma is associated with structural changes within the airways. Transforming growth factor beta TGF-P; is a potent profibrotic cytokine which may contribute to the airway remodelling. To assess the clinical importance of TGF-P; in asthma we have measured basal TGF- Pj concentrations in induced sputum and serum samples of asthmatic and healthy subjects using ELISA (PROMEGA, USA). 15 asthmatic patients (3 males, 12 females, mean age 37±13 yrs) and 5 controls were included. The mean TGF-p; was 3.09±0.21 ng/ml in sputum samples of asthmatics and 2.89±0.09 ng/ml in those of controls (p>0.05); 3-07±0.15 ng/ml in serum of asthmatics and 2.89±0.20 ng/ml in those of controls (p>0.05). There were nosignificant correlations between sputum TGF-P! concentration and number of total nonsquamous cells, number of eosinophils, number of lymphocytes, percent of lymphocytes in sputum samples, however percent of eosinophils slightly but insignificantly correlated with sputum TGF-p; levels (p<0.09, r=0.44). There was no difference between serum TGF-P; and sputum TGF-P। levels either in asthmatics or in controls. Furthermore, serum and sputum TGF-P; levels did not correlate with asthma severity. We conclude that TGF-P; levels in serum and sputum samples have no predictive value in diagnostic use and reflection of the asthma severity.