title: Clean technique for cryoprotectant-free vitrification of human spermatozoa.
abstract: Human spermatozoa can be successfully cryopreserved without the use of cryoprotectants through vitrification at very high warming rates. This is achieved by plunging a small amount of frozen sperm suspension into a warming medium, or a large amount of sperm suspension into an agitated warming medium. The aim of the present study was to compare the motility of human spermatozoa cryopreserved using four different methodologies of cooling and warming: cryoloops, droplets, open-pulled straws and standard open straws. Evaluation of two parameters, motility and viability rate of spermatozoa, suggests that all four methods are suitable for use in assisted reproductive technology. However, only the use of open-pulled straws as well as standard open straws allows the isolation of spermatozoa from liquid nitrogen with low potential risk of microbial contamination during freezing and storage, and is thereby a clean method of vitrification.
authors.affiliation: Department of Endocrinology and Reproductive Medicine, University of Bonn, Sigmund-Freud-Strasse 25, 53127 Bonn, Germany. vovaisachenko@yahoo.com
authors.forename: Vladimir
authors.initials: V
authors.lastname: Isachenko
authors.forename: Evgenia
authors.initials: E
authors.lastname: Isachenko
authors.forename: Markus
authors.initials: M
authors.lastname: Montag
authors.forename: Victoria
authors.initials: V
authors.lastname: Zaeva
authors.forename: Irina
authors.initials: I
authors.lastname: Krivokharchenko
authors.forename: Frank
authors.initials: F
authors.lastname: Nawroth
authors.forename: Salvatore
authors.initials: S
authors.lastname: Dessole
authors.forename: Igor I
authors.initials: II
authors.lastname: Katkov
authors.forename: Hans
authors.initials: H
authors.lastname: van der Ven
mesh_terms: D002470:Cell Survival; D015925:Cryopreservation / Q000295:instrumentation / Q000379:methods*; D003451:Cryoprotective Agents; D006801:Humans; D066298:In Vitro Techniques; D008297:Male; D009845:Oligospermia / Q000473:pathology / Q000503:physiopathology; D012662:Semen Preservation / Q000295:instrumentation / Q000379:methods*; D013081:Sperm Motility
chemical_list: D003451:Cryoprotective Agents