Effect of Human Endothelial Progenitor Cell (EPC)- or Mouse Vascular Endothelial Growth Factor-Derived Vessel Formation on the Survival of Vitrified/Warmed Mouse Ovarian Grafts.

The aim of this study was to evaluate the effectiveness of improving angiogenesis at graft sites on the survival of follicles in transplanted ovarian tissue. Matrigel containing 5 × 105 of cord blood-derived endothelial progenitor cells (EPCs) or 200 ng of mouse vascular endothelial growth factor (VEGF) was injected subcutaneously into BALB/c-Nu mice. After 1 week, vitrified/warmed ovaries from female B6D2F1 mice were subcutaneously transplanted into the injection sites. After 1, 2, and 4 weeks posttransplantation, the ovaries were recovered and subjected to histological analysis. Oocytes were collected from the transplanted ovaries, and their fertilization, embryonic development, and delivery were also observed. Vitrified/warmed ovaries transplanted into EPC- or VEGF-treated sites developed more blood vessels and showed better follicle survival than those transplanted into sham-injected sites. Normal embryonic development and consequent live births were obtained using oocytes recovered from cryopreserved/transplanted ovaries. Treatment with EPCs or VEGF could prevent the ischemic damage during the early revascularization stage of ovarian transplantation.