title: Influence of hypoxia on the domiciliation of mesenchymal stem cells after infusion into rats: possibilities of targeting pulmonary artery remodeling via cells therapies?
abstract: BACKGROUND
  Bone marrow (BM) cells are promising tools for vascular therapies. Here, we focused on the possibility of targeting the hypoxia-induced pulmonary artery hypertension remodeling with systemic delivery of BM-derived mesenchymal stem cells (MSCs) into non-irradiated rats.
  
  
  METHODS
  Six-week-old Wistar rats were exposed to 3-week chronic hypoxia leading to pulmonary artery wall remodeling. Domiciliation of adhesive BM-derived CD45- CD73+ CD90+ MSCs was first studied after a single intravenous infusion of Indium-111-labeled MSCs followed by whole body scintigraphies and autoradiographies of different harvested organs. In a second set of experiments, enhanced-GFP labeling allowed to observe distribution at later times using sequential infusions during the 3-week hypoxia exposure.
  
  
  RESULTS
  A 30% pulmonary retention was observed by scintigraphies and no differences were observed in the global repartition between hypoxic and control groups. Intrapulmonary radioactivity repartition was homogenous in both groups, as shown by autoradiographies. BM-derived GFP-labeled MSCs were observed with a global repartition in liver, in spleen, in lung parenchyma and rarely in the adventitial layer of remodeled vessels. Furthermore this global repartition was not modified by hypoxia. Interestingly, these cells displayed in vivo bone marrow homing, proving a preservation of their viability and function. Bone marrow homing of GFP-labeled MSCs was increased in the hypoxic group.
  
  
  CONCLUSIONS
  Adhesive BM-derived CD45- CD73+ CD90+ MSCs are not integrated in the pulmonary arteries remodeled media after repeated intravenous infusions in contrast to previously described in systemic vascular remodeling or with endothelial progenitor cells infusions.
authors.affiliation: LABPART-EA3852, IFR135, Université François Rabelais, Faculté de Médecine, 10 Boulevard Tonnellé, 370032 TOURS, France. gael.rochefort@med.univ-tours.fr
authors.forename: Gaël Y
authors.initials: GY
authors.lastname: Rochefort
authors.forename: Pascal
authors.initials: P
authors.lastname: Vaudin
authors.forename: Nicolas
authors.initials: N
authors.lastname: Bonnet
authors.forename: Jean-Christophe
authors.initials: JC
authors.lastname: Pages
authors.forename: Jorge
authors.initials: J
authors.lastname: Domenech
authors.forename: Pierre
authors.initials: P
authors.lastname: Charbord
authors.forename: Véronique
authors.initials: V
authors.lastname: Eder
mesh_terms: D000818:Animals; D002470:Cell Survival; D006976:Hypertension, Pulmonary / Q000473:pathology* / Q000601:surgery*; D000860:Hypoxia / Q000150:complications / Q000473:pathology* / Q000601:surgery; D007263:Infusions, Parenteral; D008297:Male; D045164:Mesenchymal Stem Cell Transplantation / Q000379:methods*; D059630:Mesenchymal Stem Cells / Q000473:pathology*; D011651:Pulmonary Artery / Q000473:pathology* / Q000601:surgery*; D051381:Rats; D017208:Rats, Wistar; D016896:Treatment Outcome