title: In vivo bio-distribution and homing of endothelial outgrowth cells in a tumour model.
abstract: BACKGROUND
  Endothelial progenitor cells (EPCs) has been reported to have the potential for advancing revascularization of ischemic tissue. However, the heterogeneous nature of these cells calls for specification of the angiogenic potential of each subtype. The purpose of this study was to gain additional insight on the homing capacity of the EPC subtype, endothelial outgrowth cells (EOCs) in tumours using a well-established tumour model.
  
  
  METHODS
  (111)Indium ((111)In) - and 5-(and-6)-carboxyfluorescein diacetate succinimidyl ester (CFSE) labelled EOCs derived from human umbilical cord blood were injected into mice with a C3H mammary carcinoma foot tumour. The subsequent capture of the EOCs was traced by estimation of activity in individual organs, autoradiography and fluorescence microscopy.
  
  
  RESULTS
  (111)In activity was found in tumour and other organs. However, varying parts of the activity originated from free (111)In lost from EOCs. Autoradiography demonstrated accumulation of (111)In activity in the tumour rim. Microscopy proved that a least part of this radioactivity originated from the presence of human derived EOCs and that those EOCs were not located in the endothelial lining of vessels, in the tumour.
  
  
  CONCLUSIONS
  The results demonstrated the presence of xenotransplanted EOCs in the rim of a C3H mammary carcinoma. They were, however, not located in the endothelial lining of the vessels, thus indicating that their effect in vasculogenesis might be mediated via paracrine mechanisms rather than differentiating into endothelial cells (ECs) in tumour vessels.
authors.affiliation: The MR Research Centre, Aarhus University hospital, and Department of Clinical Medicine, Aarhus University Hospital, Aarhus, Denmark. Electronic address: Lotte@mr.au.dk.
authors.forename: Lotte B
authors.initials: LB
authors.lastname: Bertelsen
authors.affiliation: Department of Cardiology, Aarhus University hospital, and Department of Clinical Medicine, Aarhus University, Aarhus, Denmark.
authors.forename: Mette
authors.initials: M
authors.lastname: Hagensen
authors.affiliation: Department of Experimental Clinical Oncology, Aarhus University Hospital, Aarhus, Denmark.
authors.forename: Morten
authors.initials: M
authors.lastname: Busk
authors.affiliation: Department of Neurology, the first affiliated hospital of Zhengzhou University, Zhengzhou, China.
authors.forename: Rui
authors.initials: R
authors.lastname: Zhang
authors.affiliation: Aarhus School of Engineering, Aarhus University, Aarhus, Denmark.
authors.forename: Anne S
authors.initials: AS
authors.lastname: Knudsen
authors.affiliation: Aarhus School of Engineering, Aarhus University, Aarhus, Denmark.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Nielsen
authors.affiliation: Department of Nuclear Medicine and PET Centre, Aarhus University Hospital, Aarhus, Denmark.
authors.forename: Lise
authors.initials: L
authors.lastname: Falborg
authors.affiliation: Department of Clinical Immunology, Aarhus University Hospital, Aarhus, Denmark.
authors.forename: Bjarne K
authors.initials: BK
authors.lastname: Møller
authors.affiliation: Department of Experimental Clinical Oncology, Aarhus University Hospital, Aarhus, Denmark.
authors.forename: Michael R
authors.initials: MR
authors.lastname: Horsman
authors.affiliation: The MR Research Centre, Aarhus University hospital, and Department of Clinical Medicine, Aarhus University Hospital, Aarhus, Denmark.
authors.forename: Hans
authors.initials: H
authors.lastname: Stødkilde-Jørgensen
mesh_terms: D000818:Animals; D004730:Endothelium, Vascular / Q000378:metabolism / Q000473:pathology*; D005260:Female; D005452:Fluoresceins / Q000737:chemistry*; D005456:Fluorescent Dyes / Q000737:chemistry*; D061307:Human Umbilical Vein Endothelial Cells / Q000378:metabolism; D006801:Humans; D007205:Indium Radioisotopes / Q000493:pharmacokinetics; D015674:Mammary Neoplasms, Animal / Q000378:metabolism / Q000473:pathology*; D051379:Mice; D008809:Mice, Inbred C3H; D008856:Microscopy, Fluorescence; D013388:Succinimides / Q000737:chemistry*; D014018:Tissue Distribution; D014183:Transplantation, Heterologous
chemical_list: C087165:5-(6)-carboxyfluorescein diacetate succinimidyl ester; D005452:Fluoresceins; D005456:Fluorescent Dyes; D007205:Indium Radioisotopes; D013388:Succinimides
keywords: Bio-distribution; Endothelial outgrowth cells; Homing; Tumour