MicroRNAs对儿童原发性肾病综合征Th2/Treg失衡的影响

Effects of microRNAs on the balance of Th2/Treg cells in children with idiopathic nephrotic syndrome

目的探讨microRNAs(miRNAs)对儿童原发性肾病综合征(PNS)辅助性T2细胞(Th2)/调节性T细胞(Treg)失衡的影响。方法收集2015年10月-2016年10月在深圳市儿童医院肾脏科就诊的PNS患儿40例,分为激素治疗前的初发组和激素治疗后缓解组,各20例,选取同年龄段健康儿童20名作为正常对照组。应用流式细胞术分析外周血循环中Th2和Treg细胞的比例;Real-time PCR分析Foxp3、GATA3、miR-24、miR-27、miR-155、miR-21及miR-31基因表达;ELISA分析血浆白细胞介素(IL)-4的浓度。结果与正常对照组相比,初发组PNS患儿外周血Th2比例、Th2/Treg细胞比值、相关因子GATA3mRNA的表达及血浆IL-4的浓度,GATA3/Foxp3mRNA表达比值均明显升高,而Treg比例、核心转录因子Foxp3mRNA的表达明显降低,差异均有统计学意义(t=5.64、6.15、10.22、4.37、8.52、9.93、11.01,P均<0.05);糖皮质激素治疗后的缓解组上述指标均出现逆转,差异均有统计学意义(t=5.58、5.93、10.81、3.40、8.24、9.61、8.80,P均<0.05)。与正常对照组相比,初发组miR-24、miR-27、miR-155和miR-21的表达显著降低,而miR-31的表达显著增高,差异均有统计学意义(t=9.08、9.37、5.88、7.25、6.28,P均<0.05);而糖皮质激素治疗后缓解组,上述miRNAs已趋于正常,差异均有统计学意义(t=6.02、6.24、5.71、6.62、5.79,P均<0.05)。结论急性期PNS患儿存在Th2/Treg细胞失衡,可能与miR-24、miR-27低表达所致Th2细胞过度活化及miR-155、miR-21低表达和miR-31高表达所致Treg细胞下调有关,其具体作用机制有待进一步探讨。

Objective To investigate the effects microRANs(miRNAs)on Th2/regulatory T cell(Treg)cell imbalance in children with primary nephrotic syndrome(PNS).Methods There were 40 children with PNS attending the Nephrology Department of Shenzhen Children's Hospital from October 2015 to October 2016,including 20 children with active PNS(before steroid initiation);20 children with PNS remission(after steroid therapy),and 20 healthy age-matched controls were enrolled.Circulating levels of Th2 and Treg cells were analyzed by flow cytometry.The concentration of IL-4 was determined using enzyme-linked immunosorbent assay.Real-time PCR was used to detect the gene expression levels of GATA3,Foxp3,miR-24,miR-27,miR-155,miR-21 and miR-31.ELISA analysis of plasma interleukin(IL)-4 concentrations.Results Relative to the control group,the active PNS group had a greater proportion of circulating Th2 cells,Th2/Treg cell ratio,level of Th2-related factors GATA3mRNA and concentration of IL-4,and GATA3/Foxp3mRNA expression ratio,but a lower proportion of circulating Tregs and expression of core transcription factor Foxp3mRNA(t=5.64,6.15,10.22,4.37,8.52,9.93,11.01,all P<0.05),and the above indicators in the remission group after glucocorticoid treatment were reversed(t=5.58,5.93,10.81,3.40,8.24,9.61,8.80,all P<0.05).The expression of miR-24,miR-27,miR-155 and miR-21 in the active PNS group were significantly reduced,while the expression of miR-31 was significantly increased(t=9.08,9.37,5.88,7.25,6.28,all P<0.05);the PNS in the remission group after glucocorticoid treatment had normalization of these miRNAs(t=6.02,6.24,5.71,6.62,5.79,all P<0.05).Conclusion Patients with active PNS had an imbalance of Th2/Treg cells,which might be related to the over-activation of Th2 cells caused by the low expression of miR-24,miR-27 and the down-regulation of Treg cells caused by the low expression of miR-155,miR-21 and the overexpression of miR-31;its specific mechanism should be further studied.