Levels of soluble Fas/APO-1 in patients with Behçet's disease.

The aim of this study was to quantify soluble Fas/APO-1 (sFas/APO-1) protein in the serum of patients with Behcet's disease (BD) in active and inactive stages, compared with patients with systemic lupus erythematosus (SLE) and patients with rheumatoid arthritis (RA). Soluble Fas/APO-1 was quantified using a sandwich enzyme-linked immunosorbent assay. Increased serum sFas/APO-1 levels were observed in active BD, compared with inactive BD, RA patients and SLE patients. Increased serum sFas/APO-1 levels were correlated with the presence of neurologic manifestations or pulmonary involvement in active BD. In conclusion, increased levels of sFas/APO-1 occurred frequently and exclusively in active BD patients. Preliminary evidence suggested that elevated levels of sFas/APO-1 are associated with the clinical stage and clinical manifestations in BD.