Interest in preserving spermatozoa, oocytes, embryos, and gonadal tissues is growing for a variety of applications. These include human fertility preservation, improvement of breeding efficiency in livestock animals, and the conservation of endangered species / maintenance of animal biodiversity. Furthermore, the long-term preservation of the germplasm is essential also for biomedical research involving animal models and genetically modified populations.
Living cells and tissues can be cryopreserved for a long period of time using low temperatures. The main methods for preservation using cryogenics are slow freezing, in which cells are progressively cooled to -196°C, vitrification, an ultra-rapid process in which the liquid phase of a cell or tissue solidifies into a glassy phase without ice crystal formation, and lyophilization or freeze-drying, a process in which ice in a frozen material under a vacuum is sublimated. While slow frozen and vitrified samples need to be stored in liquid nitrogen, lyophilization has the advantage that storage can be achieved at room temperature.
In the last decades, the efficiency of cryopreservation has increased with the advancement of knowledge about cryoprotective agents and the control of cooling and warming rates through the use of novel tools and equipment. However, there are still some challenges that need to be overcome. For instance, there are species-specific differences in the cryobiological properties of various cell types and tissues, and distinct approaches are required for different cells in the same species; oocyte cryopreservation in animals is not as effective as in human; lyophilization damages sperm membranes and assisted fertilization is required to obtain viable embryos; and, finally, gonadal tissue preservation is still intriguing because of cell heterogeneity and the complex structure of such tissues.
The goal of this Research Topic is to collect and highlight recent advances in the area of germplasm cryopreservation in different species and stimulate a comparative approach. Original research papers and review articles related to the cryopreservation of animal gametes, embryos, and gonadal tissues fall into the scope of this topic.
Interest in preserving spermatozoa, oocytes, embryos, and gonadal tissues is growing for a variety of applications. These include human fertility preservation, improvement of breeding efficiency in livestock animals, and the conservation of endangered species / maintenance of animal biodiversity. Furthermore, the long-term preservation of the germplasm is essential also for biomedical research involving animal models and genetically modified populations.
Living cells and tissues can be cryopreserved for a long period of time using low temperatures. The main methods for preservation using cryogenics are slow freezing, in which cells are progressively cooled to -196°C, vitrification, an ultra-rapid process in which the liquid phase of a cell or tissue solidifies into a glassy phase without ice crystal formation, and lyophilization or freeze-drying, a process in which ice in a frozen material under a vacuum is sublimated. While slow frozen and vitrified samples need to be stored in liquid nitrogen, lyophilization has the advantage that storage can be achieved at room temperature.
In the last decades, the efficiency of cryopreservation has increased with the advancement of knowledge about cryoprotective agents and the control of cooling and warming rates through the use of novel tools and equipment. However, there are still some challenges that need to be overcome. For instance, there are species-specific differences in the cryobiological properties of various cell types and tissues, and distinct approaches are required for different cells in the same species; oocyte cryopreservation in animals is not as effective as in human; lyophilization damages sperm membranes and assisted fertilization is required to obtain viable embryos; and, finally, gonadal tissue preservation is still intriguing because of cell heterogeneity and the complex structure of such tissues.
The goal of this Research Topic is to collect and highlight recent advances in the area of germplasm cryopreservation in different species and stimulate a comparative approach. Original research papers and review articles related to the cryopreservation of animal gametes, embryos, and gonadal tissues fall into the scope of this topic.
