title: Canine gut dendritic cells in the steady state and in inflammatory bowel disease.
abstract: Alongside the intestinal border, dendritic cells (DCs) sample large amounts of endogenous and potentially pathogenic antigens followed by initiation of protective immune responses or induction of tolerance. Breakdown of oral tolerance towards commensal bacteria is suggested to be crucial for the development of both human and canine inflammatory bowel disease (IBD). The aim of this study was to investigate canine intestinal DCs in the steady state and in dogs with IBD using multicolour immunofluorescence. In the healthy gut, DC-like cells expressed MHC II, CD1a8.2 and CD11c, and, in lower amounts, CD11b, within lamina propria, Peyer's patches (PPs) and mesenteric lymph nodes (MLNs), whereas those expressing CD80 and CD86 were only present in PPs and MLNs. Occasionally, DC-like cells were in contact with the intestinal lumen through transepithelial projections. In canine IBD, CD1a8.2+, CD11b+ and CD11c+ DC-like cells were decreased within the stomach, duodenum and colon, whereas the colonic mucosa revealed elevation of CD86+ DC-like cells. The complex network of DC-like cells in the gut indicates their important role in canine mucosal immunity, including active sampling of luminal antigens. Furthermore, their shift in diseased dogs suggests a pathogenetic significance for canine IBD.
authors.affiliation: 1Department of Pathology, University of Veterinary Medicine Hannover, Hannover, Germany.
authors.forename: Johannes
authors.initials: J
authors.lastname: Junginger
authors.forename: Frederik
authors.initials: F
authors.lastname: Lemensieck
authors.forename: Peter F
authors.initials: PF
authors.lastname: Moore
authors.forename: Ulrike
authors.initials: U
authors.lastname: Schwittlick
authors.forename: Ingo
authors.initials: I
authors.lastname: Nolte
authors.forename: Marion
authors.initials: M
authors.lastname: Hewicker-Trautwein
mesh_terms: D000818:Animals; D017951:Antigen Presentation; D015703:Antigens, CD / Q000378:metabolism; D002454:Cell Differentiation; D002478:Cells, Cultured; D003713:Dendritic Cells / Q000276:immunology*; D018450:Disease Progression; D004285:Dogs; D005455:Fluorescent Antibody Technique; D000949:Histocompatibility Antigens Class II / Q000378:metabolism; D006801:Humans; D018928:Immunity, Mucosal; D015212:Inflammatory Bowel Diseases / Q000276:immunology*; D007422:Intestines / Q000276:immunology* / Q000382:microbiology / Q000473:pathology; D064307:Microbiota / Q000276:immunology
chemical_list: D015703:Antigens, CD; D000949:Histocompatibility Antigens Class II
keywords: DC; Dog; IBD; enteropathy; gastrointestinal