Vainer B, Nielsen O H, Hendel J, Horn T, Kirman I
Department of Medicine M, Division of Gastroenterology, Glostrup Hospital, University of Copenhagen, Denmark.
Cytokine. 2000 Oct;12(10):1531-6. doi: 10.1006/cyto.2000.0744.
A dysregulated local immune reaction with unbalanced cytokine expression seems essential in inflammatory bowel disease (IBD), i.e. ulcerative colitis (UC) and Crohn's disease (CD). Since the roles of interleukin (IL-)13 and IL-15 remain unclear, this study aimed at studying intestinal expression of IL-13 and IL-15 in IBD.
In colonic biopsies from 24 UC, 18 CD, and 12 controls IL-13 and IL-15 were measured using ELISA, and their gene expressions were assessed by RT-PCR. Leukocytes were visualised histochemically.
Concentrations of IL-13 were decreased in UC (median 56 pg/mg tissue; interquartile range 30-99 pg/mg) compared to CD (82 pg/mg tissue; 41-122;P=0.004) and controls (83 pg/mg tissue; 18-134;P>0.05), and lower in active UC (53 pg/mg tissue; 33-96) than in inactive UC (80 pg/mg tissue; 65-99;P=0.02). IL-15 concentrations were higher in CD patients (34 pg/mg tissue; 24-53) as compared to controls (20 pg/mg tissue; 15-21;P=0.001) whilst being 22 pg/mg tissue (15-32) in UC. IL-13 mRNA and IL-15 mRNA were detected in 20% and 15%, respectively. Infiltration of leukocytes correlated inversely with IL-13 levels (P=0.02).
Active UC is associated with decreased colonic IL-13 suggesting that IL-13 levels are diminished as a part of UC exacerbations, or that exacerbations follow active downregulation of IL-13.
炎症性肠病（IBD），即溃疡性结肠炎（UC）和克罗恩病（CD）中，局部免疫反应失调以及细胞因子表达失衡似乎至关重要。由于白细胞介素（IL-）13和IL-15的作用仍不清楚，本研究旨在研究IBD中IL-13和IL-15的肠道表达情况。
采用酶联免疫吸附测定法（ELISA）检测24例UC、18例CD患者及12例对照者结肠活检组织中IL-13和IL-15的浓度，并通过逆转录聚合酶链反应（RT-PCR）评估其基因表达。采用组织化学方法对白细胞进行可视化检测。
与CD患者（82 pg/mg组织；四分位间距41 - 122）及对照者（83 pg/mg组织；18 - 134；P>0.05）相比，UC患者IL-13浓度降低（中位数56 pg/mg组织；四分位间距30 - 99 pg/mg），且活动期UC患者（53 pg/mg组织；33 - 96）的IL-13浓度低于非活动期UC患者（80 pg/mg组织；65 - 99；P = 0.02）。与对照者（20 pg/mg组织；15 - 21；P = 0.001）相比，CD患者IL-15浓度更高（34 pg/mg组织；24 - 53），而UC患者IL-15浓度为22 pg/mg组织（15 - 32）。分别在20%和15%的样本中检测到IL-13 mRNA和IL-15 mRNA。白细胞浸润与IL-13水平呈负相关（P = 0.02）。
活动期UC与结肠IL-13降低有关，提示IL-13水平降低是UC病情加重的一部分，或者病情加重是IL-13主动下调的结果。
