Live offspring from vitrified blastocysts derived from fresh and cryopreserved ovarian tissue grafts of adult mice.
Ovarian tissue cryopreservation and transplantation can be used to preserve fertility for cancer patients. In this study, we assessed the viability and function of ovarian tissue from adult mice that was cryopreserved by solid surface vitrification or traditional slow-cooling using various in vitro and in vivo techniques, including allotransplantation, in vitro oocyte maturation, embryo culture in vitro, blastocyst cryopreservation, embryo transfer, and development. The importance of cumulus cells for oocyte maturation, fertilization, and embryo development was investigated. Graft recovery, follicle survival, and oocyte retrieval was similar in control, vitrified, and slow-cooled groups. High rates of oocyte maturation, cleavage, and blastocyst formation were achieved, with no significant differences between the control, vitrified or slow-cooled ovarian tissue grafts. The presence of cumulus cells was important for oocyte maturation, fertilization, and subsequent development. Cumulus-oocyte complexes with no surrounding cumulus cells (N-COCs) or with an incomplete layer (P-COCs) had significantly lower rates of oocyte maturation and blastocyst formation than cumulus-oocyte complexes with at least one complete layer of cumulus cells (F-COCs; maturation rate: 63, 78 vs 94%; blastocyst rate: 29, 49 vs 80%). Live births were achieved using vitrified blastocysts derived from oocytes taken from vitrified and slow-cooled ovarian tissue heterotypic allografts. Successful production of healthy offspring from these vitrified blastocysts suggests that this technique should be considered as a useful stage to pause in the assisted reproduction pathway. This provides an alternative protocol for restoring fertility and offering cancer patients a better indication of their chances of pregnancy and live birth.
Wang
Xiaoqian
X
Monash Institute of Medical Research, Centre of Reproduction and Development, Monash University, Clayton, Victoria 3168, Australia.
Catt
Sally
S
Pangestu
Mulyoto
M
Temple-Smith
Peter
P
D000367:Age Factors; D000818:Animals; D000831:Animals, Newborn; D001755:Blastocyst; D015925:Cryopreservation; D047108:Embryonic Development / Q000502:physiology; D005260:Female; D059247:Fertility Preservation / Q000379:methods / Q000662:veterinary; D006085:Graft Survival / Q000502:physiology; D050498:Live Birth / Q000662:veterinary; D051379:Mice; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D010053:Ovary / Q000637:transplantation*; D011247:Pregnancy; D014021:Tissue Preservation / Q000379:methods; D058989:Vitrification