title: Ionized calcium-binding adaptor molecule 1 positive macrophages and HO-1 up-regulation in intestinal muscularis resident macrophages.
abstract: Small intestinal muscularis externa macrophages have been associated with interstitial cells of Cajal. They have been proposed to play various roles in motility disorders and to take part in a microbiota-driven regulation of gastrointestinal motility. Our objective was to understand the reaction of resident macrophages of the musculature to a pro-inflammatory stimulator, lipopolysaccharide (LPS). Mice were injected with LPS or saline and sacrificed after 6 hr. Whole mounts were stained with antibodies toward CD169, ionized calcium-binding adaptor molecule 1 (iba1) (microglial/macrophage marker) and heme oxygenase-1 (HO-1). Cell densities were measured using unbiased stereology.
  
  
  RESULTS
  iba1poscells showed an overall higher density than CD169posand HO-1poscells. Most HO-1posand iba1poscells were positive for CD 169 in serosa and at Auerbach's plexus (AP). At the deep muscular plexus, mainly iba1poscells were present, and were mostly CD169neg; a few HO-1poscells were present.
  
  
  CONCLUSIONS
  A new subset of resident macrophages in the intestinal muscularis externa was discovered, identified as iba1posCD169neg. HO-1 is constitutively present in most macrophages in serosa and at AP, suggesting a M2 phenotype. LPS-treatment results in an up-regulation of HO-1pos/CD169negcells in serosa and at AP. Anat Rec, 300:1114-1122, 2017. © 2016 The Authors. The Anatomical Record published by Wiley Periodicals, Inc. on behalf of American Association of Anatomists.
authors.affiliation: Department of Cellular and Molecular Medicine, University of Copenhagen, Denmark.
authors.forename: Hanne B
authors.initials: HB
authors.lastname: Mikkelsen
authors.affiliation: Department of Medicine Faculty of Health Sciences, Farncombe Family Digestive Health Research Institute McMaster University, Canada.
authors.forename: Jan D
authors.initials: JD
authors.lastname: Huizinga
authors.affiliation: Department of Neuroscience and Pharmacology, University of Copenhagen, Denmark.
authors.forename: Jytte O
authors.initials: JO
authors.lastname: Larsen
authors.affiliation: Department of Oral Medicine Faculty of Health Sciences, University of Copenhagen, Denmark.
authors.forename: Svend
authors.initials: S
authors.lastname: Kirkeby
mesh_terms: D000818:Animals; D002135:Calcium-Binding Proteins / Q000378:metabolism*; D005260:Female; D051547:Heme Oxygenase-1 / Q000378:metabolism*; D016130:Immunophenotyping; D007583:Jejunum / Q000276:immunology*; D008070:Lipopolysaccharides; D008264:Macrophages / Q000378:metabolism*; D008565:Membrane Proteins / Q000378:metabolism*; D008810:Mice, Inbred C57BL; D008840:Microfilament Proteins / Q000378:metabolism*; D063267:Sialic Acid Binding Ig-like Lectin 1 / Q000378:metabolism*
chemical_list: C491049:Aif1 protein, mouse; D002135:Calcium-Binding Proteins; D008070:Lipopolysaccharides; D008565:Membrane Proteins; D008840:Microfilament Proteins; D063267:Sialic Acid Binding Ig-like Lectin 1; C571167:Siglec1 protein, mouse; D051547:Heme Oxygenase-1; C496542:Hmox1 protein, mouse
keywords: HO-1; LPS; iba1; immunohistochemistry; intestine; macrophages