Abstract
Background
Regulatory T (Treg) cells have anti-inflammatory and anti-autoimmune functions. The proportion and functions of Treg cells are perturbed in rheumatoid arthritis (RA) patients.
Methods
Human Treg cells were induced to amplify in vitro and cocultured with RA synovial fibroblast cells (RASFs). The proliferation and apoptosis of RASFs were determined by the cell counting kit-8 (CCK-8) assay and flow cytometry, respectively. Human Treg cells were also injected to collagen-induced arthritis (CIA) rats via the tail vein. Changes in lymphocyte subtypes and cytokines in the peripheral blood and spleen were observed by flow cytometry.
Results
After coculture with the Treg cells, the proliferation of RA synovial fibroblast cells decreased (p<0.01), and the rate of apoptosis increased (p=0.037). The human Treg cells were injected into the tail veins of collagen-induced arthritis (CIA) rats. The severity of the CIA was reduced (p<0.01) following the injection, the percentages of rat endogenous Treg cells in the peripheral blood and spleen increased significantly (p=0.007 and p<0.01, respectively), and the proportion of B cells decreased (p=0.031). The levels of interleukin IL-5 and IL-6 and the Th1/Th2 ratio in the peripheral blood were significantly decreased (p=0.013, 0.009 and 0.012, respectively). The number of NK cells and the levels of IL-4, IL-13, TNF-α, IFN-γ and GM-CSF in the peripheral blood and spleen did not change significantly.
Conclusion
These results suggest that exogenous Treg cells play a therapeutic role in RA and CIA. Treg cell treatment could serve as a therapy for RA.
Therapeutic Effect of Exogenous Treg Cells on Collagen-Induced Arthritis and Rheumatoid Arthritis