Abstract: Objective　To investigate the expression levels and significance of serum Th17-related cytokines in pediatric patients with inflammatory bowel disease（IBD）. Methods　Serum from 40 children with IBD and 21 pediatric controls without inflammatory diseases admitted between April 2017 and May 2019 to the Affiliated Children’s Hospital of Xi’an Jiaotong University were collected. Serum levels of IL-17A，IL-17F，IL-21，IL-22 and IL-25 were determined by ELISA. Results　The serum levels of IL-17A，IL-17F，IL-21 and IL-22 were significantly increased in pediatric UC and CD patients，and levels of IL-25 were significantly decreased（P＜0.05）. The serum levels of IL-17A，IL-17F and IL-21 were positively correlated with disease activity index of pediatric UC patients（P＜0.05）. The serum levels of IL-21 in pediatric UC patients were positively correlated with levels of IL-17A and IL-17F（P＜0.05）. Conclusion　Th17-related cytokines are dysregulated in serum of pediatric IBD patients，which might help to further explore the role of Th17 cells in pediatric IBD development. The serum levels of IL-17A，IL-17F and IL-21 are positively correlated with disease activity index of pediatric UC patients，indicating that IL-17A，IL-17F and IL-21 might the triggers of pediatric UC by Th17 cells.

Key words: inflammatory bowel disease, cytokine, Th17 cells, IL-17, IL-21

摘要： 目的　探讨儿童IBD患者血清中Th17相关细胞因子的表达水平及其临床意义。方法　收集2017年4月至2019年5月在西安交通大学附属儿童医院消化科住院治疗的儿童IBD患者40例，以同期21例非炎症性疾病儿童作为对照组。采集受检者血清标本，通过酶联免疫吸附试验检测白细胞介素-17A（IL-17A）、 IL-17F、 IL-21、 IL-22、 IL-25的表达水平。结果　IL-17A、 IL-17F、 IL-21和IL-22在溃疡性结肠炎（UC）及克罗恩病（CD）患儿血清中表达明显升高，IL-25明显降低（P＜0.05）；IL-17A、 IL-17F及IL-21血清水平与UC患儿疾病活动度呈正相关（P＜0.05）；IL-21在UC患儿血清中的表达与IL-17A和IL-17F的表达呈正相关（P＜0.05）。结论　Th17相关细胞因子在IBD患儿血清中表达失调，为进一步研究Th17细胞在儿童IBD中的作用提供了依据；IL-17A、 IL-17F、 IL-21血清水平与UC患儿疾病活动度呈正相关，表明其可能是Th17细胞触发儿童UC的重要促炎细胞因子。

关键词: 炎症性肠病, 细胞因子, Th17细胞, IL-17, IL-21