Effect Of Metformin On The Balance Of Th17/Treg Cells In Peripheral Blood Of Patients With Rheumatoid Arthritis And Its Efficacy Evaluation

Objective:1.To study the changes of lymphoid immune cells and CD4+ T lymphocyte subsets in peripheral blood of RA patients and their correlation with disease activity indicators(ESR,DAS28);2.To investigate the effect of long-term use of glucocorticoids combined with DMARDs to primary lymphoid immune cells and CD4+ T cell subsets;3.To investigate the effect of metformin on the balance of Th17/Treg in peripheral blood of RA patients and evaluate its efficacy.Methods:According to the RA diagnostic criteria established by ACR/EULAR in 2009,90 patients with RA were included in RA group,and 50 healthy people with gender and age matched in the control group.We extracted their peripheral blood for ESR testing and used flow cytometry to determine the absolute counts of primary lymphoid immune cells and CD4+ T subsets.Then we collected their clinical data including the number of swollen joints(SJC)and tender joints(TJC),VAS score and the calculated DAS28 score.Based on whether glucocorticoids and/or DMARDs were used in the past 6 months,the RA group was divided into the treated RA group(n=52)and the untreated RA group(n=38).Finally 32 cases of RA patients were given metformin orally(250 mg/time and 2 times/day for 12 weeks).Once the treatment was completed,we detect ESR and the absolute number of Th17 and Treg cells,as well as the DAS28 score.Results:1.Compared with the normal control group,the absolute CD4+ T cell count and the CD4+T/CD8+T ratio increased in the RA group(P=0.003vsP=0.002),the difference was statistically significant;The number of T,B,CD8+T,and T+B+NK cells had an upward trend,and the number of NK cells had a decreasing trend,but there was no statistically significant.2.Compared with the normal control group,absolute count of Th1 and Th17 cells in RA group increased(P=0.008vsP=0.032),Treg cell count and Th1/Th2 ratio decreased(P=0.000 vs P=0.018),and Th17/Treg ratio increased too(P=0.000).The difference was statistically significant;3.Absolute count of T,B,CD4+T,CD8+T,NK,T+B+NK,Th1,Th2,Th17 cells and CD4+T/CD8+T ratio,Th1/Th2 ratio,Th17/Treg ratio had no correlation with ESR and DAS28 in RA group.But the Treg cell count was negatively correlated with ESR(r=-0.6275,P<0.05),and also negatively correlated with DAS28 score(r=-0.579,P<0.05).4.Compared with the normal control group,the absolute count of CD4+T and Th17 cell and the ratios of CD4+T/CD8+T and Th17/Treg were increased,and absolute count of Th2 cell was also increased both in the treated and untreated group.However,there was no significant difference in absolute count of lymphocyte and CD4+ T cell subsets between the RA group and the untreated RA group.5.Compared with before,the absolute count of Treg cells increased(P=0.02)and Th17/Treg ratio decreased in the RA group after Met treatment(P=0.013).The difference was statistically significant.The absolute count of Th17 cells increased,but the difference had no statistical significance.Compared with the normal control group,the absolute count of Th17 and Treg cells in the RA group had an increasing trend,and the Th17/Treg ratio had a decreasing trend.However,there was no statistically significant difference between these two groups.6.The indicators of disease activity(ESR,DAS28)were decreased in the RA group after metformin treatment(P=0.043vsP=0.013).Conclusion:1.The absolute count of Th1 and Th17 cells in peripheral blood of RA patients increased,while the absolute count of Treg cells decreased,and Th17/Treg imbalance exists in RA.2.The absolute count of Treg cells was negatively correlated with RA disease activity.3.Metformin can correct the imbalance of Th17/Treg in RA patients by inducing the proliferation of Treg cells,and also can effectively control the disease activity.However,the role of Th17 cells in this process is not yet clear.