An Immunohistochemical Study of Histiocytic Ulcerative Colitis in Boxer Dogs

• Published in: Journal of comparative pathology 2000-02, Vol.122 (2-3), p.163-175
• Main Authors: German, A.J., Hall, E.J., Kelly, D.F., Watson, A.D.J., Day, M.J.
• Format: Article
• Language: English
• Subjects: Animals; Breeding; CD3 Complex - analysis; Cell Count; Colitis, Ulcerative - metabolism; Colitis, Ulcerative - pathology; Colitis, Ulcerative - veterinary; Colon - chemistry; Colon - pathology; Dog Diseases - metabolism; Dog Diseases - pathology; Dogs; Epithelial Cells - cytology; Epithelial Cells - immunology; Female; Histocompatibility Antigens Class II - analysis; Histocytochemistry; Immunoglobulin A - analysis; Immunoglobulin G - analysis; Immunoglobulin M - analysis; Immunohistochemistry; Leukocyte L1 Antigen Complex; Male; Membrane Glycoproteins - analysis; Neural Cell Adhesion Molecules - analysis; Periodic Acid-Schiff Reaction; Plasma Cells - cytology; Plasma Cells - immunology; Retrospective Studies; T-Lymphocytes - cytology; T-Lymphocytes - immunology
• ISSN: 0021-9975; 1532-3129
• DOI: 10.1053/jcpa.1999.0353

Histiocytic ulcerative colitis (HUC) is an inflammatory bowel disease (IBD) that occurs predominantly in dogs of the boxer breed. The lesions are characterized by mucosal ulceration and mixed inflammatory cell infiltrate that includes the presence of periodic acid-Schiff (PAS)-positive macrophages. However, the phenotype of the inflammatory cells has not been characterized further. In the present study, immunohistochemistry and computer-aided morphometric analysis were used to define populations of leucocyte subsets in the colon of 14 boxer dogs with HUC. Biopsies from six of these dogs included both lesional and non-lesional regions. Colonic tissue from 11 dogs of various breeds without evidence of gastrointestinal disease served as controls. In HUC lesions there were significantly more IgG+, IgG3+, IgG4+plasma cells, CD3+T cells, MHC class II+cells, L1+cells and PAS+cells in the lamina propria than in both control colon and non-lesional colonic regions of affected dogs. In the epithelial compartment, goblet cells were significantly decreased in HUC lesions compared to both control and non-lesional HUC colon, and intensity of enterocyte MHC class II expression was significantly increased. These observations are similar to those documented in human IBD, especially ulcerative colitis, and suggest an important role for the mucosal immune system in the pathogenesis of canine HUC.