Free Access
Vet. Res.
Volume 40, Number 6, November-December 2009
Number of page(s) 11
Published online 28 July 2009
How to cite this article Vet. Res. (2009) 40:58
How to cite this article: Vet. Res. (2009) 40:58
DOI: 10.1051/vetres/2009042

Phenotyping, functional characterization, and developmental changes in canine intestinal intraepithelial lymphocytes

Nicole Luckschander1, 2, Nadia S. Pfammatter1, 2, Daniel Sidler1, Sabine Jakob1, Iwan A. Burgener2, Peter F. Moore3, Andreas Zurbriggen2, Nadia Corazza1 and Thomas Brunner1

1  Division of Immunopathology, Institute of Pathology, University of Bern, Murtenstrasse 31, 3010 Bern, Switzerland
2  Department of Clinical Veterinary Medicine, Vetsuisse Faculty, University of Bern, Länggasstrasse 128, 3012 Bern, Switzerland
3  Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California, Rm. 1126 Haring Hall, Davis, CA 95616, USA

Received 18 March 2009; accepted 23 July 2009; published online 28 July 2009

Abstract - Little is currently known about the lymphocyte populations in the normal and diseased canine gut. The aim of this study was thus the phenotypical and functional characterization of canine intestinal intraepithelial lymphocytes (IEL). IEL were isolated from full-thickness biopsies of 15 adult Swiss Beagle dogs (mean age $8.2 \pm 2.8$ years) and compared to mesenteric lymph node cells. The phenotypical characterization by multi-parameter flow cytometry revealed that canine IEL differ substantially from lymph node T cells, and consist of various unconventional lymphocyte subsets, unique to mucosal surfaces. These include $\gamma\sigma$ T cells, and CD4-CD8- and CD8 $\alpha\alpha^+$ T cells. IEL populations in adult dogs were also compared to those isolated from neonatal Beagle dogs. Analysis revealed a high frequency of undifferentiated CD4-CD8- T cells in newborn dogs whereas mature CD4+ and CD8+ T cells predominate in adult dogs, indicating maturation of the intestinal immune system during development. As IEL in other species are thought to exhibit regulatory functions, we investigated the role of IEL on the activation-induced proliferation of lymph node T cells. While IEL alone did not show activation-induced proliferation, they significantly inhibited the proliferation of activated lymph node T cells in a cell number-dependent manner. These findings are the first to demonstrate that canine intestinal IEL have an immunoregulatory phenotype, which may contribute to the maintenance of intestinal immune homeostasis and may, therefore, be lost in canine chronic enteropathies.

Key words: dog / intestine / intraepithelial lymphocyte

Corresponding author:

© INRA, EDP Sciences 2009