Th17/Treg细胞在儿童肺炎支原体肺炎中的作用研究

Study on the role of Th17 /Treg cells in children with mycoplasma pneumoniae pneumonia

目的:探讨Th17/Treg细胞在小儿肺炎支原体肺炎(MPP)中的作用。方法:以56例MPP患儿为研究对象,应用流式细胞术检测外周血单个核细胞(PBMC)中Th17细胞及Treg细胞的百分率;荧光定量PCR检测PBMC中转录因子RORγt及FOXP3mRNA的相对表达量;酶联免疫吸附试验(ELISA)测定各组血清中IL-17、IL-10的表达水平。结果:MPP患儿急性期Th17细胞百分率及RORγt mRNA、IL-17表达水平显著增高(P<0.01),恢复期逐渐下降,但仍高于正常(P<0.05);同时,急性期Treg细胞百分率及FOXP3 mRNA、IL-10表达水平明显减少(P<0.01),恢复期逐渐增高,但仍低于正常(P<0.05)。相关分析表明,在MPP患儿急性期,Th17细胞与IL-17及RORγt mRNA的表达呈正相关(r=0.821,0.461,P<0.05),Treg细胞与IL-10及FOXP3 mRNA的表达呈正相关(r=0.236,0.364,P<0.05),而Th17与Treg细胞的表达呈负相关(r=-0.672,P<0.05)。结论:Th17/Treg及其转录因子RORγt/FOXP3、细胞因子IL-17/IL-10参与了MPP的发生及发展过程,MPP患儿体内存在Th17与Treg细胞亚群失衡,Th17细胞占优势,两者具有相互抑制作用,随着病情的逐渐恢复,达到动态平衡。

Objective： To explore the role of Th17/Treg cells in children with mycoplasma pneumoniae pneumonia. Methods： 56 cases with mycoplasma pneumoniae pneumonia （MPP） were enrolled for research. Peripheral blood mononuclear cells （PBMC） were isolated and the percentage of Th17 cells and regulatory T （Treg） cells of PMBC were detected by flow cytometry （FCM） . The transcription factor retinoid related orphan receptor gamma t （RORγt） and forkhead boxprotein 3 （FOXP3） mRNA levels were determined by real time PCR. The expression levels of IL- 17 and IL -10 in plasma were treated by Enzyme -linked Immune Sorbent Assay （ELISA） . Results： The percentage of Th17 cells and the levels of transcription factor RORγt mRNA and IL - 17 in MPP group were significantly higher than those of the healthy control group （P 〈0. 01 ）, and which in acute period group was higher than those of alleviated period group. The Treg cell and the levels of transcription factor FOXP3 mRNA and IL - 10 in MPP group were significantly lower than those in healthy control group （ P 〈 0. 01 ）, and the levels of acute period group were significantly lower than alleviated period group （ P 〈 0. 05 ） . The correlation analysis showed that in acute period MPP patients the percentage of Th17 cells in PBMC were positively correlated with the levels of IL - 17 and RORγt mRNA expression （r =0. 821, r =0. 461, bothP 〈0. 05） ; the levels of Treg cells were positively correlated with the levels of IL - 10 and FOXP3 mRNA expression （r = 0. 236, r = 0. 364, bothP 〈 0. 05） ; the expression levels of Th17 were negatively correlated with Treg ceils （r = - 0. 672, P 〈 0. 05） . Conclusion ： Th17/Treg cells, transcription factor RORγt/FOXP3 and cytokine IL - 17/IL - 10 may be involved in the development of MPP, there is differential disorders of Th17/Treg cells , and Th17 ceils are increased obviously in children with MPP. The Th17 ceils and Treg cells inhibites each other. As patient＇s condition return to near normal gradually, Th17/Treg cells are brought into equilibrium.