Heterotopic autotransplantation of ovarian tissue in a large animal model: Effects of cooling and VEGF

PLoS One. 2020 Nov 4;15(11):e0241442. doi: 10.1371/journal.pone.0241442. eCollection 2020.

Abstract

Heterotopic and orthotopic ovarian tissue autotransplantation techniques, currently used in humans, will become promising alternative methods for fertility preservation in domestic and wild animals. Thus, this study describes for the first time the efficiency of a heterotopic ovarian tissue autotransplantation technique in a large livestock species (i.e., horses) after ovarian fragments were exposed or not to a cooling process (4°C/24 h) and/or VEGF before grafting. Ovarian fragments were collected in vivo via an ultrasound-guided biopsy pick-up method and surgically autografted in a subcutaneous site in both sides of the neck in each mare. The blood flow perfusion at the transplantation site was monitored at days 2, 4, 6, and 7 post-grafting using color-Doppler ultrasonography. Ovarian grafts were recovered 7 days post-transplantation and subjected to histological analyses. The exposure of the ovarian fragments to VEGF before grafting was not beneficial to the quality of the tissue; however, the cooling process of the fragments reduced the acute hyperemia post-grafting. Cooled grafts compared with non-cooled grafts contained similar values for normal and developing preantral follicles, vessel density, and stromal cell apoptosis; lower collagen type III fibers and follicular density; and higher stromal cell density, AgNOR, and collagen type I fibers. In conclusion, VEGF exposure before autotransplantation did not improve the quality of grafted tissues. However, cooling ovarian tissue for at least 24 h before grafting can be beneficial because satisfactory rates of follicle survival and development, stromal cell survival and proliferation, as well as vessel density, were obtained.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Apoptosis / drug effects
  • Caspase 3 / metabolism
  • Cell Count
  • Cell Proliferation / drug effects
  • Cold Temperature*
  • Female
  • Fibrosis
  • Horses
  • Models, Animal
  • Ovarian Follicle / blood supply
  • Ovarian Follicle / drug effects
  • Ovarian Follicle / transplantation*
  • Platelet Endothelial Cell Adhesion Molecule-1 / metabolism
  • Regional Blood Flow / drug effects
  • Stromal Cells / cytology
  • Stromal Cells / drug effects
  • Transplantation, Autologous
  • Transplantation, Heterotopic*
  • Vascular Endothelial Growth Factor A / pharmacology*

Substances

  • Platelet Endothelial Cell Adhesion Molecule-1
  • Vascular Endothelial Growth Factor A
  • Caspase 3

Grant support

Research supported by Coordination for the Improvement of Higher Education Personnel (CAPES; Special Visiting Researcher Grant #88881.064955/2014-01; E.L. Gastal and D.I.A. Teixeira). Samara S. de Souza was the recipient of a doctorate scholarship from the National Council for Scientific and Technological Development (CNPq), Brazil. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.