毛细支气管炎CD4+CD25+调节性T细胞和Foxp3 mRNA表达及与IgE关系

Relationship of levels of CD4+CD25+ regulatory T cells and expression of Foxp3 mRNA in peripheral blood with serum immunoglobulin E level in children with bronchiolitis

摘要:

目的：通过对呼吸道合胞病毒(RSV)毛细支气管炎患儿CD4+CD25+调节性T细胞（CD4+CD25+Treg）、Foxp3 mRNA的表达、IgE合成的检测，以探讨其在RSV毛细支气管炎发病机制中的作用。方法：在RSV检测阳性的57例毛细支气管炎患儿中，运用流式细胞仪检测外周血CD4+CD25+Treg的比例，RT-PCR检测Foxp3 mRNA的表达量、ELISA法检测血清总IgE含量。25例健康儿童作为对照组。结果：毛细支气管炎患儿外周血CD4+CD25+Treg细胞数量减少，特应性体质（7.7±1.6%）和非特应性体质组（8.8±2.1%）均低于对照组（10.5±1.6%）（P均<0.01）。毛细支气管炎特应性体质和非特应性体质组外周血Foxp3 mRNA表达亦均低于对照组（P<0.01）。而血清总IgE含量毛细支气管炎特应性体质（241.2±102.5 IU/mL）和非特应性体质组(125.5±63.2 IU/mL)均高于对照组(27.2±10.5 IU/mL)（P<0.01）。外周血CD4+CD25+Treg细胞数量、Foxp3 mRNA表达及血清总IgE含量在毛细支气管炎特应性体质和非特应性体质组之间差异有显著性意义。CD4+CD25+Treg、Foxp3 mRNA与血清IgE水平之间相关密切，r=-0.70，-0.79(均P<0.01)。结论：毛细支气管炎外周血淋巴细胞CD4+CD25+Treg和Foxp3 mRNA表达降低，二者低水平表达使IgE合成增多，共同参与了RSV毛细支气管炎的发病。［中国当代儿科杂志，2009，11（5）：349-353］

Abstract:

OBJECTIVE: To study the roles of CD4+CD25+ regulatory T cells and Foxp3 mRNA in peripheral blood as well as serum total immunoglobulin E (IgE) in the pathogenesis of bronchiolitis caused by respiratory syncytial virus (RSV). METHODS: The proportion of CD4+CD25+ regulatory T cells and expression of Foxp3 mRNA in peripheral blood, and total serum IgE level were tested by flow cytometry, RT-PCR and ELISA respectively in 57 children with RSV bronchiolitis (26 atopic patients and 31 nonatopic patients). Twenty five healthy children were used as the control group. RESULTS: The proportion of CD4+CD25+ regulatory T cells in peripheral blood in children with bronchiolitis, either in the atopic (7.7±1.6%)or the nonatopic group (8.8±2.1%), was significantly lower than that in the control group (10.5±1.6%) (P<0.01). Foxp3 mRNA expression in peripheral blood was significantly lower in both atopic and nonatopic children with bronchiolitis than that in the control group (P<0.01). Significantly increased total serum IgE level was noted in both atopic (241.2±102.5 IU/mL) and nonatopic children (125.5±63.2 IU/mL) with bronchiolitis compared with that in the control group (27.2±10.5 IU/ml) (P<0.01). There were significant differences in the proportion of CD4+CD25+ regulatory T cells and Foxp3 mRNA expression in peripheral blood (P<0.05) as well as total serum IgE level (P<0.01) between the atopic and the nonatopic group. The proportion of CD4+CD25+ regulatory T cells (r=-0.70, P<0.01) and Foxp3 mRNA expression in peripheral blood (r=-0.79, P<0.01) were closely negatively correlated to total serum IgE level. CONCLUSIONS: Both the proportion of CD4+CD25+ regulatory T cells and Foxp3 mRNA expression in peripheral blood were reduced, in contrast, the total serum IgE level increased in children with RSV bronchiolitis. This suggested that CD4+CD25+ regulatory T cells and Foxp3 mRNA together with IgE participated in the pathogenesis of RSV bronchiolitis.［Chin J Contemp Pediatr, 2009, 11 (5):349-353］