过敏性紫癜患儿外周血miR-145表达水平及其与Th1/Th2失衡的关系研究

Study on the expression of miR-145 and its relationship with Th1/Th2 imbalance in children with henoch schonlein purpura

目的探讨微小RNA-145(miR-155)在过敏性紫癜(HSP)患儿血清中的表达水平及其与Th1/Th2失衡的关系。方法选择2017年5月-2019年3月许昌市第二人民医院收治的HSP患儿101例为HSP组,并选择本院同期健康体检儿童107人为对照组。采用实时荧光定量PCR(q RT-PCR)法检测血清miR-145水平;利用流式细胞仪检测外周血中Th1细胞、Th2细胞占CD4^+T细胞的比例,并计算Th1/Th2比值;以酶联免疫吸附法(ELISA)检测两组血清γ-干扰素(IFN-γ)、白细胞介素-4(IL-4)水平;分析HSP患儿血清中miR-145、Th1、Th2、Th1/Th2水平与IFN-γ、IL-4及miR-145表达水平与Th1/Th2比值的相关性。结果HSP组患儿血清miR-145、IFN-γ表达水平及外周血Th1、Th1/Th2细胞比例明显低于对照组,IL-4水平、Th2细胞比例明显高于健康组,差异均有统计学意义(P均<0.05);HSP患儿血清miR-145水平、Th1细胞比例、Th1/Th2比值与IFN-γ水平(r=0.381、0.366、0.445,P均<0.05)、Th2细胞比例与IL-4水平(r=0.537,P<0.05)、miR-145表达水平与Th1/Th2比值均呈正相关(r=0.566,P<0.05),HSP患儿血清miR-145水平、Th1/Th2比值与IL-4水平呈负相关(r=-0.426、-0.395,P均<0.05)。结论HSP患儿血清miR-145水平、Th1/Th2比值均呈低水平,miR-145与Th1/Th2具有一定正相关性,两者可能通过相互影响,从而共同在HSP发病进程中发挥重要作用。

Objective To investigate the expression level of microRNA-145(miR-155)in serum of children with henoch schonlein purpura(HSP)and its relationship with Th1/Th2 imbalance.Methods 101 children with HSP admitted to our hospital from May 2017 to March 2019 were selected for the study,which was called HSP group,and 107 children with physical examination were selected for the control analysis,which was called control group.The serum miR-145 level was detected by real-time fluorescent quantitative PCR(QRT-PCR);the proportions of Th1 cells and Th2 cells in CD4^+T cells in peripheral blood were measured by flow cytometry,and the ratio of Th1/Th2 was calculated;the levels of interferon-γ(IFN-γ)and interleukin-4(IL-4)were detected by enzyme-linked immunosorbent assay(ELISA);the relationships between the levels of miR-145,Th1,Th2,Th1/Th2 and IFN-γ,IL-4,miR-145 and Th1/Th2 were analyzed.Results The levels of miR-145,IFN-γin serum and the proportion of Th1,ratios of Th1/Th2 cells in peripheral blood in the HSP group were significantly lower than those in the control group(P<0.05);the level of IL-4 and the proportion of Th2 cells were significantly higher than those in the control group(P<0.05);the level of miR-145,proportion of Th1 cell,ratio of Th1/Th2 and level of IFN-γ(r=0.381,0.366,0.445,P<0.05),ratio of Th2 cell and level of IL-4(r=0.537,P<0.05),expression of miR-145 and ratio of Th1/Th2(r=0.566,P<0.05)were all positively correlated,and the level of miR-145 and ratio of Th1/Th2 were negatively correlated with the level of IL-4(r=-0.426,-0.395,P<0.05).Conclusion The serum miR-145 level and Th1/Th2 ratio of HSP children were low and were positively correlated;they might play an important role in the pathogenesis of HSP through mutual influence.