LAUSR

Background ATP may be the second causative signal for the onset of gout, which acts on P2 × 7R to regulate the development of acute gouty arthritis.1Both regulatory T cells and Th17 cells are important in the development and progression of inflammatory diseases.2 Objectives To investigate the effect of P2 × 7R on Treg and Th17 cells in acute gouty arthritis model of rats and its role in acute gouty arthritis. Methods Eighty male SD rats were randomly divided into three groups: After establishment of acute gouty arthritis model, rats were given P2 × 7R agonist ATP, P2 × 7R inhibitor BBG and PBS, respectively. The rats were sacrificed at 6 hour, 12 hour, 24 hour, 48 hour and 72 hour after treatment. The spleens of the rats were grinded and the expression of Treg and Th17 cells were detected by flow cytometry. Comparison the levels and the ratio of Treg and Th17 cells at the different time points. Results (1)The expression levels of Treg and Th17 in the spleen: After treatment at 12 hour, The expression levels of Treg and Th17 in the ATP group were significantly higher than that in the BBG and control groups (p=0.001, 0.021; p=0.01, 0.025); The expression levels of Treg and Th17 in control group were higher than that in BBG group (p=0.021, 0.044); There were no significant differences in the three groups at 72 hour after treatment (p=0.052,0.116). (2).The expression trend of Treg and Th17 in different time points: the level of Treg was increased at 6 hour, but decreased gradually at12 h, 24 hour and then increased at 48 hour again; The level of Th17 was increased at 6 hour,12 h and 24 hour, but decreased gradually at 48 hour, 72 hour. (3). The ratio of Treg/Th17 gradually decreased in the first three time points, increased at 48 hour and 72 hour in three groups. The ratio of Treg/Th17 in ATP group was lower than that in BBG group and control group at 12 hour, with significant difference (p<0.05). But at other four time poins, the ratios were no significant differences among the three groups. Conclusions Activation of P2 × 7R decreased the ratio of Treg/Th17 in acute gouty arthritis rat model that showed an acute change trend along with the time, suggesting that P2 × 7R-regulated the ratio of Treg/Th17 cells affected acute gouty arthritis. References [1] Tao JH, Zhang Y, Li XP. P2X7R: a potential key regulator of acute gouty arthritis. Semin Arthritis Rheum2013;43(3):376–380. [2] Noack M. Th17 and regulatory T cell balance in autoimmune and inflammatory diseases. Autoimmunity reviews2014;13(6):668–677. Acknowledgements This work was supported by grants from the National Natural Science Foundation of China (81671601). Disclosure of Interest None declared