Assessing the tolerance to room temperature and viability of freeze-dried mice spermatozoa over long-term storage at room temperature under vacuum.
Yuko KamadaSayaka WakayamaIkue ShibasakiDaiyu ItoSatoshi KamimuraMasatoshi OogaTeruhiko WakayamaPublished in: Scientific reports (2018)
Freeze-drying has been frequently used to preserve food and microorganisms at room temperature (RT) for extended periods of time; however, its application to mammalian species is difficult. Here, we developed a method to prolong the stability of freeze-dried (FD) mice spermatozoa at RT for more than one year without using any cryoprotectant agents. Our data showed that maintaining a vacuum in ampoules is critical to ensuring the viability of FD spermatozoa, as the stability of spermatozoa DNA increased when imperfectly vacuumed ampoules were detected using a non-destructive test and eliminated. Finally a large number of healthy offspring were obtained from mice oocytes fertilized with FD spermatozoa stored at RT for more than one year. Although the birth rate from three-month stored spermatozoa was lower than that from one-day stored spermatozoa, no further reduction was observed even in one-year stored spermatozoa. Therefore, FD spermatozoa preserved in this study were highly tolerant to warm temperatures. This method of storage shows a great potential for the preservation of genetic resources of mammalian species, such as genetically-modified mouse strains, without the use of electric power.
Keyphrases
- room temperature
- ionic liquid
- high fat diet induced
- escherichia coli
- gene expression
- type diabetes
- machine learning
- high fat diet
- insulin resistance
- copy number
- electronic health record
- skeletal muscle
- adipose tissue
- genome wide
- pregnant women
- metabolic syndrome
- risk assessment
- human health
- dna methylation
- wild type
- deep learning
- climate change