支气管哮喘合并肺炎支原体感染患儿Th17/Treg细胞失衡及支原体23S rRNA基因突变情况

Th17/Treg cells imbalance and Mycoplasma 23S rRNA gene mutations in bronchial asthma children complicated with Mycoplasma pneumoniae infection

目的 探讨支气管哮喘合并肺炎支原体感染患儿外周血辅助性T细胞17(Th17)/调节性T细胞(Treg)水平、支原体23S rRNA基因突变情况及其与病情程度关系。方法 选取2017年8月-2020年8月医院收治的支气管哮喘合并肺炎支原体感染患儿120例(感染组)和未合并肺炎支原体感染支气管哮喘患儿104例(未感染组),将感染组患儿分为轻症组和重症组,流式细胞法检测外周血Th17细胞和Treg细胞百分比,酶联免疫法检测外周血白细胞介素(IL)-17、IL-6、IL-10水平,聚合酶链式反应扩增肺炎支原体23S rRNA并测序观察突变情况,Spearman分析IL-17、IL-6、IL-10与Th17、Treg关系,受试者工作特征曲线(ROC)分析Th17、Treg对重症肺炎支原体感染的鉴别价值。结果 感染组Th17细胞比例、IL-17、IL-6水平高于未感染组(P<0.05),Treg细胞、IL-10水平低于未感染组(P<0.05);重症组Th17细胞比例、IL-17、IL-6水平和23S rRNA突变检出率高于轻症组(P<0.05),Treg细胞、IL-10水平低于轻症组(P<0.05);IL-17、IL-6水平与Th17细胞比例呈正相关(P<0.05),IL-10水平与Treg细胞比例呈正相关(P<0.05);Th17、Treg细胞比例对重症肺炎支原体感染的ROC曲线下面积(AUC)分别为0.820和0.871。结论 肺炎支原体感染可加重支气管哮喘患儿的Th17/Treg细胞失衡,支原体23S rRNA基因突变在重症患儿中的检出率较高,Th17、Treg细胞比例对重症患儿有较高的鉴别价值。

OBJECTIVE To explore the levels of peripheral blood T helper cells 17(Th17)/regulatory T cells(Treg) and gene mutations of Mycoplasma 23 S rRNA in children with bronchial asthma complicated with Mycoplasma pneumoniae infection and their correlation with disease severity. METHODS A total of 120 children with bronchial asthma complicated with Mycoplasma pneumoniae infection admitted to the hospital from Aug 2017 to Aug 2020 were recruited and divided into the infection group and 104 children with bronchial asthma without pulmonary infection during the same period were enrolled as the non-infection group. The children in the infection group were divided into the mild group and severe group. The proportions of peripheral blood Th17 cells and Treg cells were detected by flow cytometry. The levels of peripheral blood interleukin-17(IL-17), IL-6 and IL-10 were detected by enzyme-linked immunosorbent assay. The polymerase chain reaction was applied to amplify 23 S rRNA of Mycoplasma pneumoniae, and sequencing was applied to observe mutations. The relationship between IL-17, IL-6, IL-10 and Th17, Treg was analyzed by Spearman. The predictive value of Th17 and Treg for severe Mycoplasma pneumoniae infection was analyzed by receiver operating characteristic(ROC) curves. RESULTS Th17 proportion, IL-17 and IL-6 levels in the infection group were significantly higher than those in the non-infection group(P<0.05), while levels of Treg and IL-10 were significantly lower than those in the non-infection group(P<0.05). Th17 proportion, IL-17 and IL-6 levels, and detection rate of 23 S rRNA mutation in the severe group were significantly higher than those in the mild group(P<0.05), while levels of Treg and IL-10 were significantly lower than those in the mild group(P<0.05). The levels of serum IL-17 and IL-6 were positively correlated with Th17 proportion(P<0.05), and IL-10 level was positively correlated with Treg proportion(P<0.05). The area under ROC curve values of Th17 and Treg for predicting severe Mycoplasma pneumoniae infection were 0.820 and 0.871, respectively. CONCLUSION Mycoplasma pneumoniae infection will aggravate Th17/Treg imbalance in children with bronchial asthma. The detection rate of Mycoplasma 23 S rRNA gene mutations is higher in the severe children. The proportions of Th17 and Treg are of high identification value for severe children.