Cryoprotectant-Free Cryopreservation of Human Spermatozoa by Vitrification and Freezing in Vapor: Effect on Motility, DNA Integrity, and Fertilization Ability
Open Access
- 1 October 2004
- journal article
- research article
- Published by Oxford University Press (OUP) in Biology of Reproduction
- Vol. 71 (4), 1167-1173
- https://doi.org/10.1095/biolreprod.104.028811
Abstract
Human spermatozoa can be successfully cryopreserved avoiding the use of cryoprotectants through vitrification at very high cooling rates (up to 7.2 × 105 °C/min). This is achieved by directly plunging a copper cryoloop loaded with a sperm suspension into liquid nitrogen. After storage, vitrified spermatozoa are instantly thawed by melting in an agitated, warm medium. The goal of the present study was to compare the quality of spermatozoa cryopreserved using this rapid vitrification method with that of spermatozoa cooled relatively slowly by preexposure of the loaded cryoloop to liquid nitrogen vapor (−160°C) with speed in the range 150–250°C/min) before immersion into liquid nitrogen. Both cooling modes led to comparable results in terms of the motility, fertilization ability, and DNA integrity of the warmed spermatozoa. In both cases, instant thawing by melting in a warm medium was essential for successful cryopreservation. Our findings suggest that optimal regimes for the cryoprotectant-free cryopreservation of spermatozoa need not be restricted to very fast cooling before storage in liquid nitrogen, a wide range of cooling rates being acceptable. Herein, we discuss the implications of this finding in the light of the physics of extra- and intracellular vitrification.Keywords
This publication has 49 references indexed in Scilit:
- Sperm Deoxyribonucleic Acid Fragmentation is Increased in Poor-Quality Semen Samples and Correlates with Failed Fertilization in Intracytoplasmic Sperm InjectionFertility and Sterility, 1998
- Improvement in quality of cryopreserved human spermatozoa by swim-up before freezingInternational Journal of Andrology, 1994
- Impact of Cryopreservation on Spermatozoa from Infertile Men: Implications for Artificial InseminationArchives of Andrology, 1994
- Freezing and thawing alter chromatin stability of ejaculated human spermatozoa: Fluorescence acridine orange staining and Feulgen‐DNA cytophotometric studiesGamete Research, 1988
- Single-strand nuclease action on heat-denatured spermiogenic chromatin.Journal of Histochemistry & Cytochemistry, 1976
- Preservation of Spermatozoa at Low TemperaturesBMJ, 1945
- REVIVAL OF MAMMALIAN SPERM AFTER IMMERSION IN LIQUID NITROGENThe Journal of general physiology, 1942
- Über die Widerstandsfähigkeit von Menschlichen Spermatozoen Gegennumber Starker K/:lteJournal of Molecular Medicine, 1938