Aims: To evaluate the expression of Fas/FasL antigen on peripheral blood T lymphocytes in patients with Behcet's disease, Vogt-Koyanagi-Harada (VKH) syndrome, and idiopathic anterior uveitis.
Methods: The expression of Fas and FasL on peripheral blood T lymphocytes was determined using flow cytometry in 26 patients with Behcet's disease (BD), 17 patients with VKH syndrome, 25 patients with idiopathic anterior uveitis, and 43 healthy individuals (controls).
Results: A higher proportion of CD4(+) T cells expressing Fas was noted in patients with Behcet's disease (25.70 +/- 7.32%), VKH syndrome (19.60 +/- 11.02%), and idiopathic anterior uveitis (20.81+/- 7.40%) compared with controls (14.02 +/- 6.30%). The expression of Fas on CD8(+) cells from patients with Behcet's disease (9.47 +/- 6.97%) and VKH syndrome (6.84+/- 5.5%) was also higher than that seen in controls (3.47+/- 2.75%). There was no difference in FasL expression on T cells between patients and controls except that a lower expression of FasL on CD8(+) T cells was noted in patients with idiopathic anterior uveitis.
Conclusion: A disturbed expression of Fas and FasL on T cells is present in patients with Behcet's disease, VKH syndrome, and idiopathic anterior uveitis, which may be involved in the perpetuation and recurrence of uveitis.