Transient CXCL‐8 Production of Buccal Epithelium in Early‐onset Crohn's Disease

Abstract

Inflammatory bowel diseases (IBD) represent an aberrant immune response by the mucosal immune system to luminal bacteria. Previously, we have compared the immunological activity of buccal epithelial cells (BEC) from children with IBD and adults with Crohn's disease. Only buccal epithelial cells from children with Crohn's disease exhibited enhanced production of the chemokines CXCL-8, CXCL-9, and CXCL-10 whereas BEC from pediatric ulcerative colitis patients, and adult Crohn's disease patients did not. In vitro stimulation with bacterial stimuli such as lipopolysaccharide or zymosan further increased chemokine release by cells from pediatric Crohn's disease patients only. Next, we determined whether the enhanced chemokine production is specifically associated with pediatric onset of Crohn's disease and present throughout life, or that this enhanced activity is exclusively present during disease in childhood. Buccal epithelial cells were obtained from 12 adults with Crohn's disease. Of them, 4 had developed CD before the age of 16 years and 8 were older than 20 years of age at CD onset. Cells were cultured with and without microbial stimulation. CXCL-8 levels were determined at 24h in culture supernatants by ELISA. Our preliminary data suggest that the enhanced immunological response of the BEC in pediatric CD is no longer present in adult life. None of the pediatric onset patients showed enhanced levels of CXCL-8, either spontaneously or in response to microbial stimulation. These results may reveal immunological alterations within the epithelial cells that are specifically associated with pediatric IBD.