小儿喘息型支气管炎肠道微生态学变化与Treg／Th17作用关系的研究

Study of relationship between intestinal microecology and Treg/Th17 in infants with asthmatoid bronchitis

目的观察喘息型支气管炎患儿肠道微生态学变化,探讨肠道菌群变化与Treg/Th17的作用关系。方法 2011年10月至2012年3月在河北医科大学第三医院采用荧光定量聚合酶链式反应(FQ-PCR)、流式细胞技术和酶联免疫吸附法(ELISA法)对47例喘息型支气管炎患儿(A组),40例急性支气管炎患儿(B组)和43例同期健康查体儿童(C组)定量测定粪便中双歧杆菌和大肠杆菌数量、外周血单个核细胞CD3+CD8-IL-17+(Th17)、CD4+CD25+T(Treg)细胞百分数和血浆IL-17、TGF-β1浓度。结果 (1)A组、B组患儿粪便中双歧杆菌数量和双歧杆菌/大肠杆菌比值(B/E值)低于C组(P<0.05),A组患儿粪便中双歧杆菌数量和B/E值低于B组(P<0.05)。(2)A组、B组患儿外周血单个核细胞Th17百分数和血浆IL-17浓度高于C组(P均<0.05);A组患儿外周血单个核细胞Treg百分数和血浆TGF-β1浓度低于B组和C组(P均<0.05)。(3)A组患儿外周血Treg/Th17低于B组和C组。(4)A组患儿粪便B/E值与Treg/Th17值呈直线正相关关系。结论喘息型支气管炎患儿发病初期即发生肠道菌群紊乱,表现在双歧杆菌数量减少和B/E值降低;Th17参与喘息型支气管炎的急性炎症反应,肠道菌群失调可能是造成Treg/Th17失衡的因素之一,并参与了疾病的病理过程。

Objective To investigate variations of intestinal microecology and the relationship between intestinal flora and Treg/Th17 in infants with asthmatoid bronchitis. Methods Forty-seven children with asthmatoid bronchitis, forty children with acute bronchitis and forty-three healthy children in the same period were enrolled into this study in the Pediatric Department of Third Hospital of Hebei Medical University from October 2011 to March 2012. 16S-rDNA fluorescent quantitative PCR was applied in determining the content of bifidobacterium and escherichia coli in feaces ; flow cytometric analysis was performed to detect the percentage of CD3＋CD8-IL-17＋（Th17） cell and CD4＋CD25＋T （Treg） cell; IL-17 and TGF-131 in plasma were detected by enzyme linked immunosorbent assay. Results （ 1 ） The amount of fecal bifidobacteria and B/E values in group A and B were lower than those in group C （P 〈 0.05 ） ; the amount of fecal bifidobacteria and B/E values in group A was lower than those in group B （P 〈 0.05 ）, （2） The percentage of Th 17 cell and the IL- 17 level in group A and B were higher than those in group C （P 〈 0.05 ） ;the percentage of Treg cell and the TGF-131 level in group A were lower than those in group B and C （P 〈 0.05）. （3）Treg/Th 17 values in group A was lower than those in group B and C （P 〈 0.05 ）. （4）There was a positive correlation between B/E ratio and Treg/Thl7 ratio in group A. Conclusion The structure of intestinal flora is disordered in early period of asthmatic bronchitis, which was expressed as reduction in number of bifidobacteria and B/E values.Thl7 cell is involved in the acute inflammatory response in asthmatic bronchitis.Reduction of probiotics in intestine may be one of the factors that lead to imbalance between Treg and Thl7, and run through pathological processes.