Patients with Active Rheumatoid Arthritis Have Lower Frequency of nTregs in Peripheral Blood

Background: Patients with rheumatoid arthritis (RA) suffer from wide ranges of autoimmune reactions in joints. The mechanism of which is generally unknown and maybe associated with Treg deregulation. Objective: To compare the frequency of nTregs in peripheral blood of patients with active rheumatoid disease with healthy individuals. Methods: Twenty five newly diagnosed patients with active RA disease were selected based on the clinical and laboratory criteria before starting their therapies. Treg cells in peripheral blood samples were enumerated by immune staining and flowcytometry analysis. Results: Clinical and laboratory results were in favor of active disease in all the studied patients although they showed variations in Disease Activity Score-28 (DAS-28). Compared to the healthy controls, RA patients had significantly lower frequency of CD4+CD25hi or CD4+CD25+FoxP3+ natural regulatory T cells. In spite of that, there were no significant differences between patients and healthy controls in respect to the CD4/CD8 ratio. Interestingly, more CD4+CD25-FoxP3+ cells were found in peripheral blood of patients. The frequencies of the Tregs did not show strong associations with the DAS-28. Conclusion: We showed lower abundance of nTregs in peripheral blood of RA patients which highlights the significance of these cells in RA.