TY - JOUR
T1 - Simple vitrification for small numbers of human spermatozoa
AU - Endo, Yuji
AU - Fujii, Yoshitaka
AU - Shintani, Kasumi
AU - Seo, Momoyo
AU - Motoyama, Hiroaki
AU - Funahashi, Hiroaki
N1 - Copyright:
Copyright 2013 Elsevier B.V., All rights reserved.
PY - 2012/3
Y1 - 2012/3
N2 - Conventional freezing procedures and containers are not appropriate for spermatozoa from the testis because of their low number and poor in-situ motility, and various types of container have been utilized to freeze small numbers of spermatozoa. This study tried to develop a vitrification method for small numbers of spermatozoa using the Cell Sleeper, which is a closed type of cell-cryopreservation container. The container with spermatozoa were cooled in liquid nitrogen vapour and then stored in a cryotank. Sperm motility parameters improved significantly (P < 0.05) by vitrification in oil-free droplets rather than in droplets covered with oil. After vitrification of five spermatozoa per container, all spermatozoa were recovered and the viable sperm rate was significantly higher when spermatozoa were vitrified in a 3.5-μl droplet rather than in 0.5 μl (72.0% versus 38.0%; P < 0.01). Recovery, motility and viability rates of vitrified-warmed spermatozoa were similar between the Cell Sleeper and the CryoTop groups. In conclusion, the Cell Sleeper is a highly effective tool for the cryopreservation of small numbers of spermatozoa and limited cells can be vitrified quickly and simply without significant loss.
AB - Conventional freezing procedures and containers are not appropriate for spermatozoa from the testis because of their low number and poor in-situ motility, and various types of container have been utilized to freeze small numbers of spermatozoa. This study tried to develop a vitrification method for small numbers of spermatozoa using the Cell Sleeper, which is a closed type of cell-cryopreservation container. The container with spermatozoa were cooled in liquid nitrogen vapour and then stored in a cryotank. Sperm motility parameters improved significantly (P < 0.05) by vitrification in oil-free droplets rather than in droplets covered with oil. After vitrification of five spermatozoa per container, all spermatozoa were recovered and the viable sperm rate was significantly higher when spermatozoa were vitrified in a 3.5-μl droplet rather than in 0.5 μl (72.0% versus 38.0%; P < 0.01). Recovery, motility and viability rates of vitrified-warmed spermatozoa were similar between the Cell Sleeper and the CryoTop groups. In conclusion, the Cell Sleeper is a highly effective tool for the cryopreservation of small numbers of spermatozoa and limited cells can be vitrified quickly and simply without significant loss.
KW - Cell sleeper
KW - CryoTop
KW - cryopreservation
KW - simple vitrification method
KW - single-sperm freezing
UR - http://www.scopus.com/inward/record.url?scp=84857921277&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84857921277&partnerID=8YFLogxK
U2 - 10.1016/j.rbmo.2011.11.016
DO - 10.1016/j.rbmo.2011.11.016
M3 - Article
C2 - 22285239
AN - SCOPUS:84857921277
VL - 24
SP - 301
EP - 307
JO - Reproductive BioMedicine Online
JF - Reproductive BioMedicine Online
SN - 1472-6483
IS - 3
ER -