title: Cytokine expression in an ex vivo culture system of duodenal samples from dogs with chronic enteropathies: modulation by probiotic bacteria.
abstract: There is evidence that probiotics have immune-modulating effects on intestinal inflammation during chronic enteropathies (CE). In an ex vivo culture system we investigated the influence of probiotics on mRNA and protein expression levels of cytokines in intestinal samples from dogs suffering from CE. Duodenal samples of client-owned dogs with CE (group CE; n = 12) were collected during diagnostic endoscopy. Additional duodenal samples of gastrointestinally healthy dogs (group C; n = 4) from an unrelated study were available. Based on histopathological analyses, no pathological changes or only mild to moderate eosinophilic and/or lymphoplasmacytic duodenitis were diagnosed. Tissue samples were cultured: (1) with cell culture medium alone (negative control), (2) with a probiotic cocktail (PC), constituted of three Lactobacilli spp. from healthy canine fecal isolates, (3) with the individual strains of PC, and (4) with a placebo powder. Viability of intestinal tissue and probiotic bacteria before and after culture was evaluated. The mRNA abundance of interleukin (IL)-10, IL-12p40, interferon (IFN)-gamma, tumor necrosis factor (TNF)-alpha, and transforming growth factor (TGF)-beta1 was analyzed by real-time polymerase chain reaction (RT-PCR). Protein concentrations of IFN-gamma and IL-10 were measured in culture supernatant by ELISA. Results of RT-PCR were expressed as 2(-2DeltaCrossing Point) x 100 after normalization with beta-actin. There was a loss of about 1 log CFU/mL of probiotic bacteria during the incubation period. Viability of tissue was maintained as confirmed by non-significant release of lactate dehydrogenase. In C, addition of PC increased IL-10 mRNA levels (P < 0.1). In CE, PC increased mRNA and protein levels of IL-10 (P < 0.05). On the mRNA level, the ratio of TNFalpha-/IL-10, IFN-gamma/IL-10, and IL-12p40/IL-10 decreased after addition of PC (P < 0.05). The results demonstrate favorable effects of PC on regulatory cytokines relative to inflammatory cytokines that might contribute to reduction of intestinal inflammation.
authors.affiliation: Division of Animal Nutrition and Physiology, Institute of Animal Genetics, Nutrition and Housing, University of Bern, Bremgartenstrasse 109A, 300 Bern, Switzerland. stephanie.sauter@kkh.unibe.ch
authors.forename: S N
authors.initials: SN
authors.lastname: Sauter
authors.forename: K
authors.initials: K
authors.lastname: Allenspach
authors.forename: F
authors.initials: F
authors.lastname: Gaschen
authors.forename: A
authors.initials: A
authors.lastname: Gröne
authors.forename: E
authors.initials: E
authors.lastname: Ontsouka
authors.forename: J W
authors.initials: JW
authors.lastname: Blum
mesh_terms: D000818:Animals; D016207:Cytokines / Q000096:biosynthesis* / Q000235:genetics / Q000276:immunology; D004283:Dog Diseases / Q000276:immunology* / Q000628:therapy; D004285:Dogs; D004386:Duodenum / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay / Q000662:veterinary; D005260:Female; D006651:Histocytochemistry / Q000662:veterinary; D066298:In Vitro Techniques; D007410:Intestinal Diseases / Q000276:immunology / Q000628:therapy / Q000662:veterinary*; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D007778:Lactobacillus / Q000276:immunology*; D008297:Male; D019936:Probiotics / Q000494:pharmacology*; D012333:RNA, Messenger / Q000737:chemistry / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000662:veterinary
chemical_list: D016207:Cytokines; D012333:RNA, Messenger; D007770:L-Lactate Dehydrogenase