COLONIC EXPRESSION AND SYNTHESIS OF INTERLEUKIN 13 AND INTERLEUKIN 15 IN INFLAMMATORY BOWEL DISEASE

• Published in: Cytokine (Philadelphia, Pa.) Vol. 12; no. 10; pp. 1531 - 1536
• Main Authors: Vainer, Ben, Nielsen, Ole H, Hendel, Jakob, Horn, Thomas, Kirman, Irena
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.10.2000
• Subjects: Adult; Aged; Biopsy; Case-Control Studies; Colitis, Ulcerative - diagnosis; Colitis, Ulcerative - metabolism; Colon - metabolism; colon/cytokines/inflammatory bowel disease/interleukin-13/interleukin-15; Crohn Disease - diagnosis; Crohn Disease - metabolism; Down-Regulation; Enzyme-Linked Immunosorbent Assay; Female; Granulocytes - metabolism; Humans; Immunohistochemistry; Inflammatory Bowel Diseases - diagnosis; Inflammatory Bowel Diseases - metabolism; Interleukin-13 - biosynthesis; Interleukin-15 - biosynthesis; Leukocytes - metabolism; Macrophages - metabolism; Male; Middle Aged; Reverse Transcriptase Polymerase Chain Reaction; colon/cytokines/inflammatory bowel disease/interleukin-13/interleukin-15
• ISSN: 1043-4666; 1096-0023
• 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. Methods: 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. Results: Concentrations of IL-13 were decreased in UC (median 56pg/mg tissue; interquartile range 30–99pg/mg) compared to CD (82pg/mg tissue; 41–122;P=0.004) and controls (83pg/mg tissue; 18–134;P>0.05), and lower in active UC (53pg/mg tissue; 33–96) than in inactive UC (80pg/mg tissue; 65–99;P=0.02). IL-15 concentrations were higher in CD patients (34pg/mg tissue; 24–53) as compared to controls (20pg/mg tissue; 15–21;P=0.001) whilst being 22pg/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). Conclusion: 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.