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Unique role of junctional adhesion molecule-a in maintaining mucosal homeostasis in inflammatory bowel disease.
- Source :
-
Gastroenterology [Gastroenterology] 2008 Jul; Vol. 135 (1), pp. 173-84. Date of Electronic Publication: 2008 Apr 11. - Publication Year :
- 2008
-
Abstract
- Background & Aims: Junctional adhesion molecule-A (JAM-A) is localized at the tight junctions and controls leukocyte migration into the tissues. However, its functional role in inflammatory bowel disease (IBD) is unexplored.<br />Methods: Control, Crohn's disease (CD), and ulcerative colitis (UC) tissue specimens were studied for JAM-A expression, as well as the colon of mice given dextran sodium sulfate (DSS). Wild-type and JAM-A(-/-), Tie-2-Cre-JAM-A(-/-) (endothelial/hematopoietic-specific JAM inactivation) mice were studied for susceptibility to DSS. Disease activity and colonic inflammation were assessed using a disease activity index histology and endoscopy, and mucosal cytokines were measured by enzyme-linked immunosorbent assay. JAM-A function was investigated by RNA silencing in epithelial cells, and apoptosis was measured.<br />Results: In both CD and UC, as well as in experimental colitis, there is a loss of epithelial but not endothelial JAM-A expression. Deletion of JAM-A results in a dramatic increase in susceptibility to DSS colitis, as assessed by weight loss, disease activity index, histologic and endoscopic severity, and strikingly high mortality rates. This is not caused by the absence of JAM-A in the endothelial or hematopoietic compartments because Tie-2-Cre-JAM-A(-/-) mice are no more susceptible to DSS colitis than wild-type animals. JAM-A(-/-) mice displayed increased intestinal permeability and inflammatory cytokine production, and marked epithelial apoptosis. Silencing of JAM-A in intestinal epithelial cells resulted in increased permeability in vitro.<br />Conclusions: Our results show a nonredundant and novel role of JAM-A in controlling mucosal homeostasis by regulating the integrity and permeability of epithelial barrier function.
- Subjects :
- Animals
Apoptosis
Cell Adhesion Molecules genetics
Cell Movement immunology
Colitis, Ulcerative metabolism
Colitis, Ulcerative pathology
Crohn Disease metabolism
Crohn Disease pathology
Cytokines metabolism
Disease Models, Animal
Down-Regulation immunology
Gene Deletion
Humans
Immunoglobulins genetics
Intestinal Mucosa immunology
Intestinal Mucosa metabolism
Intestinal Mucosa pathology
Leukocytes cytology
Leukocytes immunology
Male
Mice
Mice, Mutant Strains
Permeability
RNA Interference
Receptors, Cell Surface genetics
Receptors, Cell Surface immunology
Receptors, Cell Surface metabolism
Cell Adhesion Molecules immunology
Cell Adhesion Molecules metabolism
Colitis, Ulcerative immunology
Crohn Disease immunology
Homeostasis immunology
Immunoglobulins immunology
Immunoglobulins metabolism
Subjects
Details
- Language :
- English
- ISSN :
- 1528-0012
- Volume :
- 135
- Issue :
- 1
- Database :
- MEDLINE
- Journal :
- Gastroenterology
- Publication Type :
- Academic Journal
- Accession number :
- 18514073
- Full Text :
- https://doi.org/10.1053/j.gastro.2008.04.002