A Study of CD4+Foxp3+Treg and CD8+Foxp3+Treg Cells in Patients with Rheumatoid Arthritis

Rheumatoid arthritis (RA) is defines as a Th1 dominant disease. Tregs cell are a rather new group of T cells that regulates other immune cells including Th1 and Th2. Foxp3 is a lineage-determining factor for Treg cells. Several subsets of Foxp3+regulatory T cells are ever identified. In this study we investigated the frequency of CD4+Foxp3+Treg and CD8+Foxp3+Treg cells in patients with rheumatoid arthritis. Peripheral blood samples were obtained from 31 patients with rheumatoid arthritis and 21 healthy controls. Monoclonal antibodies including anti-CD4 and anti-CD8 and anti-Foxp3 were used and the staining process was performed. Flow cytometry were applied to evaluate the markers. The percentage of CD4+Foxp3+Treg cells was 1.03% ± 0.28 % in rheumatoid arthritis and 1.25% ± 0.3% in control group (P = 0.010). The percentage of CD8+Foxp3+ Treg cells was 0.79 ± 0.18, and 0.63 ± 0.16 in rheumatoid arthritis and control groups respectively (P = 0.002). The WBC and Lymphocytes population in rheumatoid arthritis group were higher than control group (P = 0.001). These data demonstrate that frequency of Treg cells might be involved in the pathogenesis of rheumatoid arthritis. This may be a contributory factor in the susceptibility to rheumatoid arthritis (Th1 dominant), or it may achieved during the progression of the disease.