ABSTRACT
Objective To evaluate the expression of Fas/FasL antigen on peripheral blood T lymphocytes and its possible role in Behcet disease. Methods The expression of Fas and FasL antigen on peripheral blood T lymphocytes was determined by flow cytometry and three-colour double marked immunofluorescence methods in 26 patients with Behcet disease and 43 healthy individuals. Results The difference was significant between Behcet disease (25.70%±7.32%) and controls (14.02%±6.30%) concerning the Fas expression on CD4+ T lymphocytes(P＜0.01) . But no difference was found concerning the expression of FasL antigen between Behcet disease and controls (P＞0.05).The expression of Fas antigen on CD8+ T lymphocytes from Behcet disease (9.47%±6.97%)was significantly higher than that in control group(3.47%±2.75%), but no difference was found concerning FasL antigen expression on CD8+ T lymphocytes between Behcet disease and controls(P＞0.05).Conclusion These results indicate the imbalance of the expression of Fas and FasL on T lymphocytes in Behcet disease is responsible for the perpetuation and recurrence of Behcet disease for the activated lymphocytes would not be eliminated through apoptosis mediated by Fas/FasL system.