γδT, Treg And B Cells In Pediatric Systemic Lupus Erythematosus

Objective:To analyze the immune status of γδT, Treg and B cells in newly diagnosed or treated pediatric systemic lupus erythematosus (SLE), exploring the pathogenesis of γδT, Treg and B cells in pediatric systemic lupus erythematosus and the impact of treatment on γδT and Treg subsets.Methods:Peripheral blood samples of 32 pediatric systemic lupus erythematosus patients,25 age-matched healthy donors were collected from November 2013 to January 2015. The proportion of γδT subsets, Treg subsets in peripheral blood mononuclear cells (PBMCs) were detected by flow cytometry (Flow Cytometry). The changes of proportion of B cells in the newly diagnosed pediatric SLE was also analyzed. The impact of treatment on fequency of y5T and Treg in the PBMCs was analyzed.Results: ①The proportion of peripheral γδT in newly diagnosed patients (5.08%± 2.41%) was lower than the normal healthy controls (10.24%±3.71%), the difference was statistically significant (P<0.001). The proportion of TCR 62 (3.26%±2.41%) was lower than the normal healthy controls (7.34%±3.11%), the difference was statistically significant (P<0.001). The proportion of TCRy9 subsets (4.43%±2.92%) was lower the normal healthy controls (9.05%±3.68%), the difference was statistically significant (P<0.001). The ratio of CD45RA+FoxP3+Treg (1.82%±1.35%) was similar to the normal healthy controls (1.66%± 0.79%) (P=0.66); the ratio of CD45RA-FoxP3+Treg (5.43%±3.86%) was significantly higher than the normal healthy controls (1.78%±0.90%), the difference was statistically significant (P<0.001). The ratio of CD45RA"FoxP3++ Treg (1.62%±1.64%) was similar to the normal healthy controls (0.66%±0.43%) (P=0.141). Of the 10 newly diagnosed patients, the proportion of peripheral blood CD19+CD27+B cells (4.14%±2.12%) and CD19+CD27-B cells (9.61%±4.38) was similar to the healthy controls (6.00±3.64)(P=0.31) and (8.96%±2.56%) (P=0.31) respectively. ② The proportion of γδT cell subsets and Treg subsets was not associated with the SLEDAI score. (P> 0.05) ③ The percentage of peripheral γδT, TCRγ2 and TCRy9 in treated patient was lower than healthy controls (P<0.001). Methylprednisolone(MF) treatment did not affect the proportion of γδT, TCRγ2 and TCRy9, and the ratio of RA+FoxP3+Treg, CD45RA-FoxP3++Treg and CD45RA-FoxP3+Treg showed no correlation with the use of MF (P> 0.05). The proportion of γδT subsets and Treg subsets in peripheral peripheral blood of patients with immunosuppressive therapy was similar to the patient only treated with MF.Conclusions:The proportion TCR γδT cells and TCR 2, TCRy 9 was significantly decreased in pediatric SLE patient, suggesting γδT cells have an important role in the pathogenesis of SLE. non-Treg was significantly increased n pediatric SLE patient, suggesting that Treg subsets dysregulation may contribute to immunoregulatory defects in pediatric SLE. MF and immunosuppressive drugs had no significant effect on the percentage of γδT and Treg cell subsets.