Comparative study of agarose-gel microcapsules and Cryotop in cryopreservation of extremely small numbers of human spermatozoa
Open Access
- 3 May 2021
- journal article
- research article
- Published by Taylor & Francis Ltd in Systems Biology in Reproductive Medicine
- Vol. 67 (3), 244-250
- https://doi.org/10.1080/19396368.2021.1873457
Abstract
We investigated the feasibility of agarose-gel microcapsules to cryopreserve extremely small numbers of sperm for assisted reproductive technology. Semen samples were collected from 16 patients attending the center for reproductive medicine male infertility clinic at a university hospital. We used agarose microcapsules to cryopreserve extremely small numbers of sperm from 16 patients with male infertility (10 with sperm concentration ≥1 million/mL; 6 with sperm concentration <1 million/mL). Six spermatozoa were injected into agarose-gel microcapsules and cryopreserved in a liquid nitrogen tank for 7 days. The Crytop method was used for cryopreservation as a control. After thawing, spermatozoa were recovered. Sperm recovery rates, motility and viability, and recovery time were compared. The post-thawing recovery rate, motility rate, and viability rate were higher whereas the recovery time was shorter in samples preserved using the agarose-gel microcapsule method compared to samples preserved using the Cryotop method in both the group with sperm concentrations of 1 million/mL or above and the group with sperm concentrations of less than 1 million/mL. This study demonstrated that using the agarose-gel microcapsule method increased post-thawing sperm recovery rate, sperm motility rate, and sperm viability rate, and reduced sperm recovery time compared with the conventional Cryotop method when cryopreserving samples with low sperm count. Although requiring further study, the agarose-gel microcapsule method shows much promise as a new option for freezing sperm.Keywords
Funding Information
- International Center for Reproductive Medicine, Dokkyo Medical University Saitama Medical Center, and JSPS KAKENHI
This publication has 22 references indexed in Scilit:
- The Application of Ultrasonic Vibration in Human Sperm Cryopreservation as a Novel Method for the Modification of Physicochemical Characteristics of Freezing MediaScientific Reports, 2019
- Single human sperm cryopreservation method using hollow-core agarose capsulesFertility and Sterility, 2015
- Successful delivery derived from vitrified-warmed spermatozoa from a patient with nonobstructive azoospermiaFertility and Sterility, 2012
- Simple vitrification for small numbers of human spermatozoaReproductive BioMedicine Online, 2012
- Single Spermatozoon Freezing Using CryotopJournal of Mammalian Ova Research, 2011
- Techniques for cryopreservation of individual or small numbers of human spermatozoa: a systematic reviewHuman Reproduction Update, 2008
- Cryopreservation of spermatozoa in alginic acid capsulesFertility and Sterility, 2006
- Single sperm cryopreservation on cryoloops: an alternative to hamster zona for freezing individual spermatozoaReproductive BioMedicine Online, 2004
- Cryopreservation of single human spermatozoa.Human Reproduction, 1997
- Development of an assay to assess the functional integrity of the human sperm membrane and its relationship to other semen characteristicsReproduction, 1984