title: Electron paramagnetic resonance as a tool to evaluate human ovarian tissue reoxygenation after xenografting.
abstract: OBJECTIVE
  To develop electron paramagnetic resonance (EPR) oximetry as a tool to characterize the oxygen environment in human ovarian xenografts in the early postgrafting period.
  
  
  METHODS
  Prospective experimental study.
  
  
  METHODS
  Gynecology research unit in a university hospital.
  
  
  METHODS
  Biopsies were obtained from 6 women aged 22-35 years.
  
  
  METHODS
  Frozen-thawed human ovarian tissue fragments were grafted to an intraperitoneal site in nude mice. Before grafting, lithium phthalocyanine, an oxygen reporter, was implanted inside the fragments.
  
  
  METHODS
  To monitor partial pressure of oxygen (pO(2)) by EPR on postgrafting days 3, 5, 7, 10, 14, 17, and 21 and validate the technique by histologic assessment.
  
  
  RESULTS
  A period of hypoxia was identified before day 5, followed by gradual but significant oxygenation over the next 5 days, suggesting an active process of graft revascularization. Reoxygenation kinetics in human ovarian xenotransplants were quantified.
  
  
  CONCLUSIONS
  Our data validated the EPR oximetry technique as a tool to monitor pO(2) in ovarian grafting. The critical early period of hypoxia was identified, and the first steps of reoxygenation were characterized. In the future, our model may be used to evaluate new freezing and grafting protocols with the aim of reducing potential cryoinjury and initial ischemia-reperfusion damage.
authors.affiliation: Department of Gynecology, Faculty of Medicine, Université catholique de Louvain, Louvain, Cliniques Universitaires St. Luc, Avenue Hippocrate 10, Brussels, Belgium.
authors.forename: Anne-Sophie
authors.initials: AS
authors.lastname: Van Eyck
authors.forename: Bénédicte Francine
authors.initials: BF
authors.lastname: Jordan
authors.forename: Bernard
authors.initials: B
authors.lastname: Gallez
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Heilier
authors.forename: Anne
authors.initials: A
authors.lastname: Van Langendonckt
authors.forename: Jacques
authors.initials: J
authors.lastname: Donnez
mesh_terms: D000818:Animals; D004578:Electron Spin Resonance Spectroscopy / Q000379:methods; D005260:Female; D006801:Humans; D000860:Hypoxia / Q000378:metabolism; D051379:Mice; D008819:Mice, Nude; D010053:Ovary / Q000098:blood supply / Q000378:metabolism* / Q000637:transplantation*; D010092:Oximetry; D010101:Oxygen Consumption; D014183:Transplantation, Heterologous / Q000502:physiology*