Changes of Treg/Th17 Ratio in Spleen of Acute Gouty Arthritis Rat Induced by MSU Crystals

Acute gouty arthritis is the inflammation of joint tissues in the acute form due to the deposition of monosodium urate (MSU) crystals. Regulatory T cells (Tregs) and Th17 cells play an important role in the development and progression of inflammatory diseases. However, the expression and role of Tregs and Th17 cells are not clear in this disease. Here, we investigated the changes of Tregs, Th17 cells, and Treg/Th17 ratio in spleen, as well as the inflammatory cytokines in blood and joint tissue pathology in acute gouty arthritis rat induced by MSU. We found that both the percentages of Tregs and Th17 cells in spleen increased at an early stage (6 h). Tregs decreased at 12 and 24 h, and rise again at 48 and 72 h. However, Th17 cells reached its peak at 24 h, and then decreased after 48 h. Treg/Th17 ratio showed an initial decrease and then increase, and further reached its minimum value at 24 h. But the ratios of Treg/Th17at all times were lower than that of normal control. The level of serum cytokines (IL-1β, IL-6, IL-17, TNF-α, and IL-10) showed an opposite trend to Treg/Th17 ratio, except the level of TGF-β₁ was similar to Tregs. In summary, Tregs and Th17 cells in spleen changed over time during the development of acute gouty arthritis. Decrease of Treg/Th17 ratio was consistent with inflammation development in the joints, suggesting that Treg/Th17 imbalance may involve in pathogenesis of acute gouty arthritis.