title: Effects of Ex Vivo Infection with ETEC on Jejunal Barrier Properties and Cytokine Expression in Probiotic-Supplemented Pigs.
abstract: Enterotoxigenic Escherichia coli (ETEC) strains are involved in piglet post-weaning diarrhea. Prophylactic measures including probiotics have been examined in infection experiments with live piglets. In the present study, we have tested whether the early effects of ETEC infection can also be evoked and studied in a model in which ETEC is added to whole mucosal tissues ex vivo, and whether this response can be modulated by prior supplementation of the piglets with probiotics.
  
  
  
  Jejunal barrier and transport properties of Enterococcus faecium-supplemented or control piglets were assessed in Ussing chambers. Part of the epithelia was challenged with an ETEC strain at the mucosal side. Fluxes of fluorescein as a marker of paracellular permeability, and the expression of selected tight junction (TJ) proteins and of proinflammatory cytokines were measured.
  
  
  
  The addition of ETEC ex vivo induced an increase in transepithelial resistance peaking in the first 2 h with a concomitant reduction in fluorescein fluxes, indicating tightening effects on barrier function. The response of short-circuit current after stimulation with PGE2or glucose was reduced in epithelia treated with ETEC. ETEC induced a decrease in the TJ protein claudin-4 in the control diet group after 280 min and an increase in the mRNA expression of the proinflammatory cytokines interleukin-8 and TNF-α in both groups after 180 min.
  
  
  
  The addition of ETEC ex vivo affected barrier function and transport properties of the jejunal tissues and enhanced cytokine expression. The differences in claudin-4 expression in the jejunum might indicate a beneficial effect of E. faecium prefeeding.
authors.affiliation: Institute of Veterinary Physiology, Department of Veterinary Medicine, Freie Universität Berlin, Oertzenweg 19b, 14163, Berlin, Germany. Ulrike.lodemann@fu-berlin.de.
authors.forename: Ulrike
authors.identifier: 0000-0001-5140-5356
authors.initials: U
authors.lastname: Lodemann
authors.affiliation: Institute of Veterinary Physiology, Department of Veterinary Medicine, Freie Universität Berlin, Oertzenweg 19b, 14163, Berlin, Germany.
authors.forename: Salah
authors.initials: S
authors.lastname: Amasheh
authors.affiliation: Institute of Veterinary Physiology, Department of Veterinary Medicine, Freie Universität Berlin, Oertzenweg 19b, 14163, Berlin, Germany.
authors.forename: Judith
authors.initials: J
authors.lastname: Radloff
authors.affiliation: Institute of Veterinary Physiology, Department of Veterinary Medicine, Freie Universität Berlin, Oertzenweg 19b, 14163, Berlin, Germany.
authors.forename: Martina
authors.initials: M
authors.lastname: Kern
authors.affiliation: Institute of Microbiology and Epizootics, Department of Veterinary Medicine, Freie Universität Berlin, Oertzenweg 19b, 14163, Berlin, Germany.
authors.forename: Astrid
authors.initials: A
authors.lastname: Bethe
authors.affiliation: Institute of Microbiology and Epizootics, Department of Veterinary Medicine, Freie Universität Berlin, Oertzenweg 19b, 14163, Berlin, Germany.|Robert Koch Institute, Nordufer 20, 13302, Berlin, Germany.
authors.forename: Lothar H
authors.initials: LH
authors.lastname: Wieler
authors.affiliation: Institute of Animal Nutrition, Department of Veterinary Medicine, Freie Universität Berlin, Königin-Luise-Str. 49, 14195, Berlin, Germany.
authors.forename: Robert
authors.initials: R
authors.lastname: Pieper
authors.affiliation: Institute of Animal Nutrition, Department of Veterinary Medicine, Freie Universität Berlin, Königin-Luise-Str. 49, 14195, Berlin, Germany.
authors.forename: Jürgen
authors.initials: J
authors.lastname: Zentek
authors.affiliation: Institute of Veterinary Physiology, Department of Veterinary Medicine, Freie Universität Berlin, Oertzenweg 19b, 14163, Berlin, Germany.
authors.forename: Jörg R
authors.initials: JR
authors.lastname: Aschenbach
mesh_terms: D000821:Animal Feed; D000818:Animals; D016207:Cytokines / Q000096:biosynthesis* / Q000235:genetics; D054307:Enterotoxigenic Escherichia coli; D004927:Escherichia coli Infections / Q000178:diet therapy / Q000378:metabolism / Q000517:prevention & control; D005260:Female; D015870:Gene Expression; D007413:Intestinal Mucosa / Q000187:drug effects / Q000378:metabolism* / Q000382:microbiology*; D007583:Jejunum / Q000187:drug effects / Q000378:metabolism* / Q000382:microbiology*; D008297:Male; D011247:Pregnancy; D019936:Probiotics / Q000008:administration & dosage*; D011897:Random Allocation; D013552:Swine
chemical_list: D016207:Cytokines
keywords: Cytokine; Enterotoxigenic Escherichia coli; Intestine; Pig; Probiotic; Tight junction