title: Cross-talk between intestinal epithelial cells and immune cells in inflammatory bowel disease.
abstract: Inflammatory bowel disease (IBD) involves functional impairment of intestinal epithelial cells (IECs), concomitant with the infiltration of the lamina propria by inflammatory cells. We explored the reciprocal paracrine and direct interaction between human IECs and macrophages (MΦ) in a co-culture system that mimics some aspects of IBD. We investigated the expression of intercellular junctional proteins in cultured IECs under inflammatory conditions and in tissues from IBD patients. IECs establish functional gap junctions with IECs and MΦ, respectively. Connexin (Cx26) and Cx43 expression in cultured IECs is augmented under inflammatory conditions; while, Cx43-associated junctional complexes partners, E-cadherin, ZO-1, and β-catenin expression is decreased. The expression of Cx26 and Cx43 in IBD tissues is redistributed to the basal membrane of IEC, which is associated with decrease in junctional complex proteins' expression, collagen type IV expression and infiltration of MΦ. These data support the notion that the combination of paracrine and hetero-cellular communication between IECs and MΦs may regulate epithelial cell function through the establishment of junctional complexes between inflammatory cells and IECs, which ultimately contribute to the dys-regulation of intestinal epithelial barrier.
authors.affiliation: Department of Anatomy, Cell Biology, and Physiological Sciences, Faculty of Medicine, American university of Beirut, Beirut, Lebanon.
authors.forename: Sara
authors.initials: S
authors.lastname: Al-Ghadban
authors.affiliation: Department of Anatomy, Cell Biology, and Physiological Sciences, Faculty of Medicine, American university of Beirut, Beirut, Lebanon.
authors.forename: Samira
authors.initials: S
authors.lastname: Kaissi
authors.affiliation: Inflammation group-Nature Conservation Center (NCC) for Sustainable Futures, American University of Beirut, Lebanon.
authors.forename: Fadia R
authors.initials: FR
authors.lastname: Homaidan
authors.affiliation: Department of Physiological Chemistry, University of Veterinary Medicine Hannover, Hannover, Germany.
authors.forename: Hassan Y
authors.initials: HY
authors.lastname: Naim
authors.affiliation: Department of Anatomy, Cell Biology, and Physiological Sciences, Faculty of Medicine, American university of Beirut, Beirut, Lebanon.
authors.forename: Marwan E
authors.initials: ME
authors.lastname: El-Sabban
mesh_terms: D018938:Caco-2 Cells; D015820:Cadherins / Q000378:metabolism; D002450:Cell Communication; D045744:Cell Line, Tumor; D018920:Coculture Techniques; D017630:Connexins / Q000235:genetics / Q000378:metabolism; D004847:Epithelial Cells / Q000378:metabolism*; D015870:Gene Expression; D057809:HEK293 Cells; D019073:HT29 Cells; D006367:HeLa Cells; D006801:Humans; D015212:Inflammatory Bowel Diseases / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D007413:Intestinal Mucosa / Q000473:pathology; D008264:Macrophages / Q000378:metabolism*; D062826:Zonula Occludens-1 Protein / Q000378:metabolism; D051176:beta Catenin / Q000378:metabolism
chemical_list: D015820:Cadherins; D017630:Connexins; C569042:TJP1 protein, human; D062826:Zonula Occludens-1 Protein; D051176:beta Catenin