Soluble Form of Fas and Fas Ligand in BAL Fluid From Patients With Pulmonary Fibrosis and Bronchiolitis Obliterans Organizing Pneumonia

摘要

Study objectives: The Fas-Fas ligand (FasL) pathway is a representative system of apoptosis-nsignaling receptor molecules. We previously described that this pathway may play an importantnrole in the pathogenesis of fibrosing lung diseases. In this study, we hypothesized that solublenform of Fas (sFas) and FasL (sFasL) may also be associated with this disorder.nMeasurements and results: We measured sFas and sFasL levels in BAL fluid (BALF) from patientsnwith idiopathic pulmonary fibrosis (IPF), interstitial pneumonia associated with collagen vascularndiseases (CVD-IP), and bronchiolitis obliterans organizing pneumonia (BOOP), using enzyme-nlinked immunosorbent assay. BALF from all patients was obtained before prednisolone therapy.nsFasL levels were relatively increased in IPF patients (p 5 0.084), and significantly increased innCVD-IP patients (p < 0.05) and BOOP patients (p < 0.05), compared with control subjects. BALFnsFasL levels were elevated in the IPF or CVD-IP subgroups with an indication for prednisolonentherapy, compared with those without an indication for therapy. The BALF sFasL level in IPFnpatients was correlated with the number of total cells and lymphocytes. The BALF sFasL level innBOOP patients was relatively or significantly correlated with the number of total cells ornlymphocytes, respectively. The BALF sFas level was significantly increased in BOOP patients, butnnot in IPF or CVD-IP patients.nConclusions: We conclude that BALF sFasL levels may be associated with the accumulation ofninflammatory cells and reflect the degree of lymphocyte alveolitis in IPF. The elevation of sFasLnmay be associated with the deterioration of IPF and CVD-IP. The elevation of the BALF sFasnlevel may abrogate the cytotoxicity of FasL in BOOP patients, which may be associated withnbetter prognosis of BOOP, compared with IPF or CVD-IP. (CHEST 2000; 118:451–458)