Clinical Research
Copyright ©2005 Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Oct 28, 2005; 11(40): 6338-6347
Published online Oct 28, 2005. doi: 10.3748/wjg.v11.i40.6338
Characterization of colonic dendritic cells in normal and colitic mice
Sheena M Cruickshank, Nicholas R English, Peter J Felsburg, Simon R Carding
Sheena M Cruickshank, Simon R Carding, Institute of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT, United Kingdom
Nicholas R English, Antigen Presentation Research Group, Faculty of Medicine, Imperial College, Northwick Park and St Mark’s Campus, Harrow HAI 3UJ, United Kingdom
Peter J Felsburg, Department of Clinical Science, University of Pennsylvania, Philadelphia, PA 1904, United States
Author contributions: All authors contributed equally to the work.
Supported by the National Institutes of Health (RO1 AI41562 and PO1 RR12211) to SRC and PJF
Correspondence to: Professor SimonR Carding, School of Bioch-emistry and Microbiology, University of Leeds, Leeds LS2 9JT, United Kingdom. s.r.carding@leeds.ac.uk
Telephone: +44-113-343-1404 Fax: +44-113-343-1421
Received: September 13, 2004
Revised: December 21, 2004
Accepted: December 23, 2004
Published online: October 28, 2005
Abstract

AIM: Recent studies demonstrating the direct involvement of dendritic cells (DC) in the activation of pathogenic T cells in animal models of inflammatory bowel disease identify DC as important antigen presenting cells in the colon. However, very little is known about the properties of colonic DC.

METHODS: Using immunohistochemistry, electron microscopy and flow cytometry we have characterized and compared colonic DC in the colon of healthy animals and interleukin-2-deficient (IL2-/-) mice that develop colitis.

RESULTS: In the healthy colon, DC resided within the lamina propria and in close association with the basement membrane of colonic villi. Type 1 myeloid (CD11c+, CD11b+, B220-, CD8α-) DC made up the largest (40-45%) population and all DC expressed low levels of CD80, CD86, and CD40, and had high endocytic activity consistent with an immature phenotype. In colitic IL2-/- mice, colonic DC numbers increased four- to five-fold and were localized within the epithelial layer and within aggregates of T and B cells. They were also many more DC in mesenteric lymph nodes (MLN). The majority (>85%) of DC in the colon and MLN of IL2-/- mice were type 1 myeloid, and expressed high levels of MHC class II, CD80, CD86, CD40, DEC 205, and CCR5 molecules and were of low endocytic activity consistent with mature DC.

CONCLUSION: These findings demonstrate striking changes in the number, distribution and phenotype of DC in the inflamed colon. Their intimate association with lymphocytes in the colon and draining lymph nodes suggest that they may contribute directly to the ongoing inflammation in the colon.

Keywords: Colonic dendritic cells; Interleukin 2; Colitis