Effect of Interferon Alfa-2a on Peripheral Blood CD4+CD25+ T Regulatory Cells in Patients with Behcet Uveitis: Preliminary Study

Purpose: To evaluate the phonotypical and functional effect of interferon alfa-2a therapy on peripheral blood CD4+CD25+ T regulatory (Treg) cells in patients with Behcet uveitis. Methods: Blood was taken from 5 patients with refractory Behcetpanuveitis and 5 age-matched healthy controls. Flow cytometric analysis of CD4+CD25+Treg cells was performed. CD4+CD25+Treg cells were separated by magnetic-assisted cell sorting and co-cultured. Cytokine levels in the supernatants were determined by ELISA. Results: The percentage of CD4+CD25+Foxp3+Treg cells and the intensity of Foxp3 expression of CD4+CD25+Treg cells were slightly elevated in patients when compared to controls. Interferon alfa-2a led to a borderline significant decline of CD4+CD25+Foxp3+Treg cells and elevation of interleukin-10 (p=0.06). Conclusions: Interferon alfa-2a therapy might lead to a decline in the dysfunctional CD4+CD25+Foxp3+Treg cell population. Interleukin-10 may play a major role in IFN α-2a mediated control of Behcet uveitis.