title: Endothelial cells are essential for ovarian stromal tissue restructuring after xenotransplantation of isolated ovarian stromal cells.
abstract: BACKGROUND
  Grafting of isolated follicles represents an approach to prevent the risk of reimplanting malignant cells with cryopreserved ovarian fragments. Optimal conditions and cell types required to sustain human follicular growth need to be identified. To help improve the grafting technique, we investigated whether short-term xenografting of a suspension containing ovarian stromal and endothelial cells without follicles could enhance graft survival and revascularization.
  
  
  METHODS
  In human ovary, CD34 selectively labels endothelial cells of blood vessels. A CD34-replete ovarian stromal cell group, including stromal and endothelial cells, was obtained after enzymatic digestion of fresh human ovarian cortex. Magnetic-activated cell sorting was used to establish a CD34-depleted ovarian stromal cell group. Proportions of CD34-positive cells were evaluated by flow cytometry and immunocytochemistry. Cell suspensions were embedded in human plasma clots and grafted (n = 10 for each group, 7 days) to the ovarian bursa of nude mice. Angiogenesis was quantified after human/mouse CD34 immunostaining.
  
  
  RESULTS
  CD34-replete grafts had a well-organized and vascularized stromal structure, containing tubular components staining for human CD34 and corresponding to functional vessels, as evidenced by intraluminal red blood cells. CD34-depleted grafts tended to be smaller than CD34-replete grafts and poorly vascularized with central necrosis. Global microvessel density was higher in the CD34-replete than depleted group (337.9 versus 187.3 vessels/mm(2), P < 0.05), with a greater proportion of human vessels (68.02 versus 6.95%, respectively, P < 0.05).
  
  
  CONCLUSIONS
  We demonstrated the importance of co-transplanting ovarian endothelial and stromal cells to ensure the formation of a well-vascularized and structured ovarian-like stroma after short-term xenografting, for future application in the transplantation of isolated follicles.
authors.affiliation: Department of Gynecology, Institut de Recherche Expérimentale et Clinique, Cliniques Universitaires St Luc, Université Catholique de Louvain, Avenue Hippocrate 10, 1200 Brussels, Belgium.
authors.forename: C
authors.initials: C
authors.lastname: Dath
authors.forename: A
authors.initials: A
authors.lastname: Dethy
authors.forename: A
authors.initials: A
authors.lastname: Van Langendonckt
authors.forename: A S
authors.initials: AS
authors.lastname: Van Eyck
authors.forename: C A
authors.initials: CA
authors.lastname: Amorim
authors.forename: V
authors.initials: V
authors.lastname: Luyckx
authors.forename: J
authors.initials: J
authors.lastname: Donnez
authors.forename: M M
authors.initials: MM
authors.lastname: Dolmans
mesh_terms: D000818:Animals; D018952:Antigens, CD34 / Q000276:immunology; D001777:Blood Coagulation; D042783:Endothelial Cells / Q000637:transplantation*; D005260:Female; D006085:Graft Survival; D006801:Humans; D051379:Mice; D008819:Mice, Nude; D018919:Neovascularization, Physiologic / Q000502:physiology; D006080:Ovarian Follicle / Q000637:transplantation*; D010053:Ovary / Q000098:blood supply / Q000637:transplantation*; D017154:Stromal Cells / Q000637:transplantation*; D014183:Transplantation, Heterologous
chemical_list: D018952:Antigens, CD34