Optimizing ovarian tissue quality before cryopreservation: comparing outcomes of three decortication methods on
Sonia Herraiz1, Susana Monzó2, Belén Gómez-Giménez3
1IVI Foundation, Valencia, Spain; Reproductive Medicine Research Group, Valencia, Spain.
Objective:
To evaluate whether specific ovarian decortication techniques vary in promoting ovarian cortex cryopreservation and transplant outcomes.
Design:
Experimental design.
Setting:
University hospital.
Animal(S):
Nonobese diabetic (NOD)/severe combined immunodeficiency (SCID) female mice.
Intervention(S):
Human ovarian biopsy samples allocated to one of the following decortication procedures: scratching with scalpel blade (B), cutting with microsurgical scissors (M), separation with slicer (S), or no-separation (control, C). Parallel, in vivo experiment: decortication techniques combined with slow freezing (SF) and vitrification (VT) before xenograft into immunodeficient mice.
Main Outcome Measure(S):
Follicular counts, apoptosis, shear stress, Hippo pathway and inflammation. In vivo: recovered grafts analyzed for follicular counts, angiogenesis, proliferation, and fibrosis.
Result(S):
There were no differences in follicular density or number of damaged follicles between the decortication techniques in the in vitro study. Nevertheless, the M samples showed statistically significantly increased stromal damage compared with the controls and S samples, and up-regulation of Hsp60 shear stress gene expression. Decortication by both M and S inhibited the Hippo pathway, promoting gene expression changes. In the 21-day xenograft, total follicular density statistically significantly decreased compared with the nongrafted controls in all groups. Nevertheless, no differences were observed between the decortication techniques. Ovarian stroma vascularization was increased in the vitrified samples, but among the slow-freezing samples, the B samples had the lowest microvessel density. The M decorticated xenografts had increased fibrosis.
Conclusion(S):
Decortication with a slicer causes less damage to ovarian tissue than other commonly used methods although microsurgical scissors seem to preserve slightly increased follicular numbers. Nevertheless, blade decortication seems to be a reliable technique for maintaining acceptable follicular conditions without inducing serious stromal impairment.
Insights
Ovarian decortication techniques impact tissue damage and transplant outcomes. Slicer (S) method shows less damage, while blade (B) is reliable for preserving follicles without stromal impairment.
Area of Science:
- Reproductive biology and cryobiology.
- Ovarian tissue cryopreservation and transplantation research.
Background:
- Ovarian cortex cryopreservation is crucial for fertility preservation.
- Decortication is a necessary step before cryopreservation, but techniques may affect tissue viability.
- Evaluating different decortication methods is essential for optimizing ovarian tissue banking.
Purpose of the Study:
- To compare the effects of different ovarian decortication techniques on ovarian cortex cryopreservation and subsequent transplant outcomes.
- To assess the impact of decortication methods on follicular integrity, stromal damage, and molecular pathways.
Main Methods:
- Human ovarian biopsy samples underwent four decortication procedures: scalpel blade (B), microsurgical scissors (M), slicer (S), and no-separation control (C).
- In vitro analysis included follicular counts, apoptosis, and gene expression (Hippo pathway, shear stress).
- In vivo xenograft model in immunodeficient mice evaluated decortication techniques combined with slow freezing (SF) or vitrification (VT), assessing follicular density, angiogenesis, proliferation, and fibrosis.
Main Results:
- In vitro: No significant differences in follicular density or damage between techniques. Microsurgical scissors (M) caused increased stromal damage and Hsp60 expression. Both M and S inhibited the Hippo pathway.
- In vivo: Follicular density decreased in all xenografts compared to controls, with no technique differences. Vitrified samples showed increased stromal vascularization.
- Slow-frozen (SF) samples: Blade (B) had the lowest microvessel density. Microsurgical scissors (M) xenografts exhibited increased fibrosis.
Conclusions:
- Slicer (S) decortication minimizes ovarian tissue damage compared to other methods.
- Microsurgical scissors (M) may preserve slightly more follicles but cause greater stromal damage.
- Blade (B) decortication offers a reliable method for maintaining acceptable follicular conditions with minimal stromal impairment.
