P024 Role of Interleukin 27 (IL-27) in the Colonic Mucosa of Patients with Inflammatory Bowel Disease.
G. Fonseca Camarillo*1, F.-C. Janette2, Y.F. Jesús Kazuo3
1Instituto Nacional de Ciencias Médicas y Nutrición, Salvador Zubirán. México D.F, México., Inflammatory Bowel Disease Clinic. Department of Gastroenterology. , Distrito Federal, Mexico, 2Instituto Nacional de Ciencias Médicas y Nutrición, Salvador Zubirán. México D.F, México., Department of Gastroenterology, Mexico City, Mexico, 3Instituto Nacional de Ciencias Médicas y Nutrición, Salvador Zubirán. México D.F, México., Inflammatory Bowel Disease Clinic. Department of Gastroenterology., Mexico City, Mexico
The pathogenesis of inflammatory bowel disease (IBD) is not completely understood. The chronic relapsing inflammation is thought to be the result from a pro-inflammatory microenvironment and an aberrant immune response. The interleukin 27 (IL-27) is an immune-regulatory cytokine, has both anti- and pro-inflammatory properties. As an anti-inflammatory, IL-27 seems to induce a general negative feedback program that limits T and NK-T cell activity and also mediates inflammation during chronic disease. Nevertheless, no previous studies have explored their expression in patients with IBD.
This is an observational and cross sectional study, we included a total of 30 active UC (aUC), 22 inactive UC (iUC), 20 active CD (aCD), and 20 inactive CD (iCD) patients and 30 patients as control group (without endoscopic and histological evidence of intestinal inflammation). Gene expression was measured by real time polymerase chain reaction (RT-PCR). Protein expression was detected in tissue by immunohistochemistry. The Dunn´s Test was used for all pairwise comparisons and comparisons against the control group following rank-based ANOVA
The IL-27 gene expression was significantly elevated in control group versus active UC (P=0.04) and inactive UC (P=0.02). The IL-27 expression was increased in patients with active CD compared to inactive CD (P=0.03). We also found a decrease expression of IL-27 among active CD versus non-inflamed tissues. In order to determine in situ the IL-27 protein expression in intestinal tissue from IBD patients, tissues were immunostained and compared with non-inflamed tissue. The percentage of IL-27 immunoreactive cells was higher in active UC compared with CD patients and controls. The IL-27***producing cells were found mainly in mucosa, submucosa, muscularis, adventitia and perivascular inflammatory. The IL-27 was synthesized largely by epithelial cells, endothelial cells and lymphocytes.
The IL-27 gene expression and producing cells in active UC patients were increased compared with non-inflamed tissues and CD patients. We found different gene expression of IL-27 between UC and CD groups. This cytokine might significantly shape and differentiate inflammatory process, severity, and tolerance loss between UC and CD pathophysiology. Additional studies are required about IL-27 in the gut mucosal immune response in order to confirm the role of this cytokine in patients with IBD.