目的：观察白介素13（IL-13）在小儿类固醇敏感肾病综合征（SRNS）中的变化及甲基泼尼松龙冲击治疗（MPT）对IL-13表达的影响，探讨其在SRNS发病中的作用。方法：分别采用ELISA法及RT-PCR法测定20例正常儿童及28例SRNS患儿MPT前、结束后2 d、5 d、尿蛋白转阴后2周血清IL-13水平及外周血单个核细胞(PBMC) IL-13 mRNA水平。采用双缩脲法对SRNS患儿检测24 h尿蛋白量。结果：血清IL-13蛋白水平及PBMC IL-13 mRNA表达MPT前明显高于MPT结束后5 d组、尿蛋白转阴后2周组及正常对照组，差异有显著性（均P＜0.01）；MPT结束后5 d组较正常对照组高，差异有显著性（P＜0.05）； MPT前与结束后2 d比较差异无显著性（P＞0.05）。尿蛋白转阴后2周组血清IL-13蛋白水平及PBMC IL-13 mRNA表达与正常对照组比较无统计学意义。SRNS患儿血清中IL-13水平与24 h尿蛋白量呈正相关。结论：SRNS患儿血清IL-13及其基因表达异常，MPT对SRNS患儿IL-13在蛋白合成和基因转录两个水平上可能有抑制作用。［中国当代儿科杂志，2007，9（6）：533-536］

OBJECTIVE: To study serum concentration and mRNA expression of interleukin-13 (IL-13) in children with steroid-responsive nephrotic syndrome (SRNS) and the effect of methylprednisolone pulse therapy (MPT) on IL-13 expression. METHODS: Twenty-eight children with SRNS were enrolled in this study. Serum protein level of IL-13 was measured using ELISA and IL-13 mRNA expression in peripheral blood mononuclear cells (PBMC) was detected with RT-PCR before MPT, 2 and 5 days after MPT, and 2 weeks after disappearance of proteinuria following MPT. Twenty-four urinary protein was measured with the biuret assay. Twenty healthy children were used as controls. RESULTS: Serum IL-13 levels (38.48±13.01 pg/mL vs 5.18±2.71 pg/mL) and PBMC IL-13 mRNA expression (1.31±0.23 vs 0.36±0.07) before MPT in SRNS patients were significantly higher than in the controls. After 5 days of MPT and 2 weeks after disappearance of proteinuria following MPT, serum IL-13 levels (15.33±7.81 and 5.35±2.12 pg/mL respectively) and PBMC IL-13 mRNA expression (0.89±0.26 and 0.33±0.08 respectively) were significantly reduced (P<0.01). Serum IL-13 levels and PBMC IL-13 mRNA expression in SRNS patients 2 weeks after disappearance of proteinuria following MPT were reduced to control levels, but remained at a higher level than controls 5 days after MPT. A positive correlation was found between serum levels of IL-13 and 24-hour urinary protein in SRNS patients before (r=0.75, P < 0.01) and after 2 and 5 days of MPT (r=0.68, r=0.71 respectively; P <0.05). ConclusionsSerum IL-13 levels and PBMC IL-13 mRNA expression in children with SRNS increase. MPT can inhibit the expression of protein and mRNA of IL-13 in these patients.［Chin J Contemp Pediatr, 2007, 9 (6):533-536］