Bio-inspired solute enables preservation of human oocytes using minimum volume vitrification

Abstract

The ability to cryopreserve human oocytes has significant potential for fertility preservation.Current cryopreservation methods still suffer from the use of conventional cryoprotectants, such as dimethyl sulphoxide (DMSO), causing loss of viability and function. Such injuries result from the toxicity and high concentration of cryoprotectants, as well as mechanical damage of cells due to ice crystal formation during the cooling and rewarming processes. Here we report the preservation of human oocytes following vitrification using an innovative bio-inspired cryoprotectant integrated with a minimum volume vitrification approach. The results demonstrate that the recovered human oocytes maintained viability following vitrification and rewarming. Moreover, when this approach was used to vitrify mouse oocytes, the recovered oocytes preserved their viability and function following vitrification and rewarming. This bioinspired approach substitutes DMSO, a well-known toxic cryoprotectant, with ectoine, a nontoxic naturally occurring solute. The bio-inspired vitrification approach has the potential to improve fertility preservation for women undergoing cancer treatment and endangered mammal species. KEYWORDSbio-inspired material, ectoine, human oocyte, low level of cryoprotectants, naturally inspired, vitrification

iPSC-Derived Ovarian Tissue Restores Ovarian Function in Subfertile Mice and After Gonadotoxic Chemotherapy

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Antifreeze Proteins: Novel Applications and Navigation towards Their Clinical Application in Cryobanking

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Bioinspired Preservation of Natural Killer Cells for Cancer Immunotherapy

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