Effect Of Glucocorticoid On The Expression Of Regulatory B Cells And Th17 Cells In Primary Immune Thrombocytopenia

Objective:Primary immune thrombocytopenia (ITP) is currently defined as an acquired autoimmune disorder characterized by decreased platelet production and excessive platelet destruction, increased risk of bleeding. In recent years, cellular immune abnormalities have attracted increasing attention in ITP pathogenesis. This experiment, we detected the frequency of peripheral regulatory B cells (Bregs) and Th17 cells in ITP patients with before and after the application glucocorticoid therapy, and normal control group by flow cytometry. To explore the role of Bregs and Th17 in the pathogenesis of ITP, the effect of glucocorticoid on they expression, and the correlation of platelet count with Bregs, Thl7 cells in ITP patients before and after therapy.Methods:Collected 27 cases of newly diagnosed ITP outpatient or inpatient in the lanzhou university second hospital during June 2014 to January 2015 who all were used conventional-dose prednisone (1mg/kg/d) therapy and reduced gradually after 2 weeks when platelets returned to normal.17 cases over the same period in our hospital examination of healthy subjects as control group, we detected the frequency of peripheral Bregs (CD19+CD24hiCD38hi)/CD19+ and Th17(CD3+CD8-IL-17+)/CD4+ cells in ITP patients before therapy, after 4 weeks of therapy and control groups by flow cytometry.Result:ITP group Bregs/CD19+ cells ratio before treatment was significantly lower than the healthy controls (1.19±0.77 vs 2.54±0.83)% and with statistical significance (P<0.001) Bregs/CD19+ceils ratio after treatment was significantly higher than before treatment (2.33 ± 0.75 vs 1.19 ± 0.77)%, the difference was statistically significant (P= 0.002), but compared with the control group showed no significant difference (P> 0.05); ITP group Th17/CD4+ cells ratio before treatment was significantly higher than the healthy control group (2.60 ± 0.95 vs 1.16 ± 0.60)%, the difference was statistically significant (P<0.001). Th17/CD4+ cells after treatment reduced the proportion compared with pre-treatment (1.51 ± 0.77 vs 2.60 ± 0.95)%, the difference was statistically significant (P= 0.003), but compared with the control group showed no significant difference (P> 0.05); ITP group Bregs/CD19+(%) with Th17/CD4+(%) before and after treatment are negatively correlated, the difference was statistically significant(P< 0.01). ITP patients before-after treatment Bregs/CD19+(%) difference between the platelet count(×109/L) difference showed a positive correlation, and the difference was statistically significant (P<0.01), Th17/CD4+(%) difference between the platelet count (×109/L) difference have no correlation.Conclusion:The proportion of Bregs cells decreased in patients with ITP, the proportion of Th17 cells incressed, Bregs/Th 17 imbalance involved in the pathogenesis of ITP. Glucocorticoid therapy may increase the expression of Bregs cells, decrease the expression of Th17 cells, and the change between platelet and Bregs in ITP is relevant. The ratio of Bregs and Th17 cells before and after treatment is negative correlated, suggesting that Bregs may play a role in the negative immune regulation by inhibiting Th17 cells.