title: Vitrification of mouse pronuclear oocytes with no direct liquid nitrogen contact.
abstract: The ability to routinely cryopreserve human oocytes and embryos represents a significant advancement in the field of assisted reproductive technology. Although the method of slow freezing is commonly employed, research on the alternative technique of vitrification is promising. Vitrification involves incubation of the cell in a cryoprotectant rich solution, which permits a glass-like state to occur almost instantaneously in liquid nitrogen. A number of different techniques have been invented for holding oocytes and embryos in the cryoprotectant solution during rapid vitrification and subsequent storage. Most of these involve direct contact with liquid nitrogen. Recently, concerns have been raised regarding the sterility of such a method and the potential of viral contamination from the liquid nitrogen. The present study shows that the previously reported Cryoloop method can be used to vitrify and store embryos without direct liquid nitrogen contact (during vitrification and storage). When such vitrified embryos are warmed, they are capable of subsequent development comparable with non-vitrified embryos.
authors.affiliation: Colorado Centre for Reproductive Medicine, 799 East Hampden Avenue, Suite 520, Englewood, CO 80113, USA. mlarman@colocrm.com
authors.forename: Mark G
authors.initials: MG
authors.lastname: Larman
authors.forename: Courtney B
authors.initials: CB
authors.lastname: Sheehan
authors.forename: David K
authors.initials: DK
authors.lastname: Gardner
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D015925:Cryopreservation / Q000295:instrumentation / Q000379:methods*; D003451:Cryoprotective Agents / Q000737:chemistry*; D003470:Culture Media / Q000737:chemistry*; D005260:Female; D051379:Mice; D009584:Nitrogen; D009865:Oocytes; D027724:Reproductive Techniques, Assisted; D013997:Time Factors
chemical_list: D003451:Cryoprotective Agents; D003470:Culture Media; D009584:Nitrogen