Establishment of the ovarian tissue cryopreservation protocol on bovine model

Abstract

Ovarian tissue cryopreservation is a suitable method for fertility preservation on women receiving treatment that may threaten the ovarian function and subsequent fertility. The whole ovarian or a part of ovarian can be cryopreserved for future use. This study was aimed to establish ovarian tissue cryopreservation protocols on bovine model for human application in Vietnam. In this method, bovine ovarians were collected from a slaughterhouse and kept at 4 ^oC up to a maximum of 12 hours before doing experiments. The ovarian cortex was cut into pieces of 10x10x1 mm. These pieces were randomly divided into 3 groups: (1) fresh species (control group), (2) species were freezed by slow-freezing method and (3) pieces were freezed by vitrification. After thawing, ovarian cortex pieces were treated with Collagenase Ia for the follicle isolation. The isolated follicles then were stained with Neutral Red. The rate of viable follicles was used as the outcome measure to assess the efficiency of the cryopreservation protocol. In results, the rates of viable follicles were 72.46 ± 6.11 % and 59.09 ± 7.08 % after slow-freezing and vitrification comparing to the control group, respectively. This was the first study which successfully established a protocol of ovarian tissue cryopreservation on bovine model in Vietnam. The protocol should be improved for further application to human treatment in the near future.