title: The role of osteopontin in recovery from hind limb ischemia.
abstract: OBJECTIVE
  Osteopontin (OPN) is a highly phosphorylated extracellular matrix glycoprotein that is involved in a diversity of biological processes. In the vascular wall, OPN is produced by monocytes/macrophages, endothelial cells, and smooth muscle cells, and it is thought to mediate adhesion, migration, and survival of these cell types. In this study, we hypothesized that OPN plays a critical role in recovery from limb ischemia.
  
  
  RESULTS
  We induced hind limb ischemia in wild-type and OPN-/- mice. OPN-/- mice exhibited significantly delayed recovery of ischemic foot perfusion as determined by LDPI, impaired collateral vessel formation as measured using micro-CT, and diminished functional capacity of the ischemic limb. In the aortic ring assay, normal endothelial cell sprouting was found in OPN-/- mice. However, OPN-/- peritoneal monocytes/macrophages were found to possess significantly reduced migration in response to chemoattraction.
  
  
  CONCLUSIONS
  This study provides evidence that a definitive biological role exists for OPN during ischemic limb revascularization, and we have suggested that this may be driven by impaired monocyte/macrophage migration in OPN-/- mice. These findings provide the first in vivo evidence that OPN may be a key regulator in postnatal vascular growth.
authors.affiliation: Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, USA.
authors.forename: Craig L
authors.initials: CL
authors.lastname: Duvall
authors.forename: Daiana
authors.initials: D
authors.lastname: Weiss
authors.forename: Scott T
authors.initials: ST
authors.lastname: Robinson
authors.forename: Fadi M F
authors.initials: FM
authors.lastname: Alameddine
authors.forename: Robert E
authors.initials: RE
authors.lastname: Guldberg
authors.forename: W Robert
authors.initials: WR
authors.lastname: Taylor
mesh_terms: D000818:Animals; D042783:Endothelial Cells / Q000502:physiology*; D006614:Hindlimb / Q000098:blood supply; D007511:Ischemia / Q000503:physiopathology*; D035002:Lower Extremity / Q000098:blood supply* / Q000503:physiopathology; D008264:Macrophages / Q000502:physiology; D008297:Male; D051379:Mice; D018919:Neovascularization, Physiologic / Q000502:physiology*; D053495:Osteopontin / Q000235:genetics / Q000502:physiology*; D020127:Recovery of Function / Q000502:physiology*
chemical_list: C506896:Spp1 protein, mouse; D053495:Osteopontin