S Fas in bronchoalveolar lavage fluid of patients with sarcoidosis in relation to cigarette smoking.

Sarcoidosis is a multiorgan granulomatous disease with frequent spontaneous remission. Apoptosis is postulated to participate in the granuloma resolution. Soluble Fas (sFas) is known to inhibit Fas-induced apoptosis. The aim of this study was to determine the sFas concentration in the BALf of ever smoking (S) and never smoking (NS) patients with sarcoidosis. We investigated 57 patients with confirmed SA: 36 NS and 21 S. The sFas concentration was measured by ELISA method. The sFas concentration was lower in the BALf of patients S group compared with NS (median values 68.3 vs. 96.1 pg/mL, p=0.07) and it was significantly lower in active smokers when compared with NS (62.9 vs. 96.1 pg/mL, p=0.03). There was a significant correlation between sFas concentration and proportion of lymphocytes and negative relation with macrophage proportion. Lower concentration of sFas in smoking SA patients may result in higher apoptosis rate of inflammatory cells and hereby promote resolution of granulomas.