5岁以下喘息患儿哮喘预测指数与外周血单核细胞TLR4表达的相关性研究

Correlation between Toll-like receptor 4 in peripheral blood monocytes and asthma predictive index in wheezing children under 5 years of age

目的探讨5岁以下喘息患儿外周血单核细胞(PBMCs)表面Toll样受体4(TLR4)及血清白细胞介素6(IL-6)的表达。方法选取该院门诊或住院患儿共224例,其中哮喘预测指数(API)阳性组116例,阴性组108例。两组患儿均在喘息症状缓解1个月后分别抽取外周血,流式细胞仪检测PBMCs TLR4阳性率,酶联免疫吸附法(ELISA)检测血清IL-6水平。结果 API阳性组患儿CD14^+单核细胞表面TLR4阳性率明显高于API阴性组[(34.9±10.0)%vs.(30.2±8.8)%];API阳性组患儿血清IL-6水平明显高于API阴性组[(46.4±15.1)ng/Lvs.(40.5±13.6)ng/L];且两组TLR4阳性率和IL-6水平均呈线性相关(P<0.05)。结论 TLR4的激活诱导IL-6等细胞因子表达可能和哮喘的发生、发展有关,TLR4可能可以作为喘息发展为哮喘的预测指标。

Objective To study the expression of Toll-like receptor 4（TLR4）in peripheral blood mononuclear cell（PBMCs）and serum interleukin-6（IL-6）in wheezing children under 5years of age.Methods A total of 224 wheezing children under 5years of age were divided into API（asthma predictive index）-positive（n=116）and API-negative groups（n=108）.Serum level of IL-6and TLR4 expression on CD14＋monocytes were measured after wheezing was stable for one month.TLR4 expression on CD14~＋ monoeytes was quantified via flow-cytometry.Serum level of IL-6was detected by ELISA.Results Serum level of IL-6and TLR4 expression on CD14~＋ monocytes of API-positive group were higher than API-negative group [LR4（%）：34.9±10.0 vs.30.2±8.8;IL-6（ng/L）：46.4±15.1 vs.40.5±13.6].There was a significant positive correlation between the expression of TLR4 and the content of serum IL-6in two groups of wheezing children（P〈0.05）.Conclusion TLR4 may play a role in the pathogenesis of asthma through promoting the expression of IL-6.TLR4 may be a index to predicting asthma in wheezing children.