Cyclosporine A Suppresses the Activation of the Th17 Cells in Patients with Primary Sjögren's Syndrome

Primary Sjögren's syndrome (pSS) is a common autoimmune disease involving abnormal Th17 activation. The aim of the current study was to investigate the immunosuppression effect of Cyclosporine A (Cys A), a potent immunosuppressor on the proliferation and activation of T cells, on the activation of Th17 cells. Blood samples from both inactive and active pSS patients as well as healthy controls were collected and serum and peripheral blood mononuclear cells (PBMCs) were collected and tested for IL-17 and RORγt expression. Subsequently, PBMCs were treated in vitro with Cys A in a series of doses and incubation time and the effect of Cys A on inhibiting Th17 activation was tested by measuring IL-17 and RORγt expression. IL-17 in both serum and PBMCs as well as RORγt in PBMCs from active pSS patients were significantly elevated on both the mRNA and protein levels comparing to those from both inactive pSS patients and healthy controlCys A in the final concentration of 80ng/ml and the treatment time of 24h showed strong inhibition effect on the expression of IL-17 and RORγt in PBMCs from active pSS patients. However, Cys A in various doses and incubation times did not show much impact on inhibiting IL-17 as well as RORγt expression in PBMCs from healthy donors and inactive pSS patients. Cys A possesses the capability in immunosuppressing the activation of Th17 cells, suggesting that Cys A may be a potential treatment for pSS and maybe other autoimmune diseases.