title: Effects of malnutrition on the expression of daintain/AIF-1 in the gut mucosa of pigs.
abstract: The allograft inflammatory factor (AIF-1/daintain) is a hormone-like peptide produced by activated monocytic cells in a variety of traumatic, inflammatory and degenerative lesions. Gut-derived AIF-1 has been shown to modulate insulin production and to attenuate autoimmune diabetes. As the localization of this gastrointestinal peptide in the porcine duodenum is not known and the pig is a convenient model for the study of nutritional modulation of the mucosal immune compartment, we have localized expression of AIF-1 by immunohistology in the duodenum of either malnourished (energy and protein supply 50% of demands, n = 5) or optimally fed pigs (n = 5). AIF-1 macrophages were predominantly located at the villus tip. The number of positively stained cells per high-power field was significantly (P < or = 0.001) higher in the malnourished pigs (74.6 +/- 2.44; least square means +/- SEM) compared to optimally fed pigs (32.56 +/- 1.99). It is likely that the effect in malnourished pigs can be explained by a more pronounced antigen contact of macrophages due to loss of epithelial integrity. Thus, AIF-1 is a novel marker for the study of the nutritional regulation of the mucosal immune system of the pig. AIF-1 expression in the duodenum was further validated by polymerase chain reaction and sequencing. Surprisingly, we detected a slight deviation from the original sequence (probably representing an allelic variation) and an AIF-1 splice variant, previously not known to occur in pigs.
authors.affiliation: Universität Hohenheim, Institut für Tierhaltung und Tierzüchtung, FG Tierhaltung und Leistungsphysiologie, Stuttgart, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Mentschel
authors.forename: M H
authors.initials: MH
authors.lastname: Deininger
authors.forename: H J
authors.initials: HJ
authors.lastname: Schluesener
authors.forename: R
authors.initials: R
authors.lastname: Claus
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002135:Calcium-Binding Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D018076:DNA, Complementary / Q000737:chemistry; D004386:Duodenum / Q000166:cytology / Q000276:immunology / Q000378:metabolism; D018928:Immunity, Mucosal; D007150:Immunohistochemistry / Q000662:veterinary; D007413:Intestinal Mucosa / Q000166:cytology / Q000276:immunology / Q000378:metabolism*; D008264:Macrophages / Q000276:immunology / Q000378:metabolism; D008297:Male; D008969:Molecular Sequence Data; D009748:Nutrition Disorders / Q000276:immunology / Q000378:metabolism / Q000662:veterinary*; D016133:Polymerase Chain Reaction / Q000662:veterinary; D017386:Sequence Homology, Amino Acid; D013552:Swine; D013553:Swine Diseases / Q000276:immunology / Q000378:metabolism*
chemical_list: D002135:Calcium-Binding Proteins; D018076:DNA, Complementary