CD4Foxp3 T-Regulatory Cells in Noninfectious Uveitis

Methods: Patients with uveitis were evaluated for CD4Foxp3 T-regulatory cells by flow cytometry. Systemic and ocular diagnoses, disease activity, and the presence of cystoid macular edema were reviewed. Percentages of CD4Foxp3 lymphocytes were compared for patients with inactive vs active disease, systemic vs ocular diagnoses, and the presence or absence of cystoid macular edema. Real-time polymerase chain reaction testing was performed on 2 patients with extremely low CD4Foxp3 cell populations to assess Foxp3 mRNA. Results: A total of 20 patients with intermediate uveitis, posterior uveitis, and panuveitis were evaluated. The mean age was 40.6 years and the mean visual acuity was 20/57. Percentages of CD4Foxp3 cells were lower in patients with active compared with inactive uveitis (P.05). No differences in T-regulatory cells were observed between the other subgroups. Two patients with recalcitrant uveitis who demonstrated less than 1% CD4Foxp3 lymphocytes showed extremely low or absent Foxp3 mRNA. Conclusion: T-regulatory cells are reduced in patients with active compared with inactive disease. Severe depletion of CD4Foxp3 T cells and Foxp3 mRNA in 2 patients with severe uveitis suggests that loss of the T-regulatory cells of uveitis may be a salient feature in certain patients.