The individual-cell-based cryo-chip for the cryopreservation, manipulation and observation of spatially identifiable cells. I: methodology.
BACKGROUND
Cryopreservation is the only widely applicable method of storing vital cells for nearly unlimited periods of time. Successful cryopreservation is essential for reproductive medicine, stem cell research, cord blood storage and related biomedical areas. The methods currently used to retrieve a specific cell or a group of individual cells with specific biological properties after cryopreservation are quite complicated and inefficient.


RESULTS
The present study suggests a new approach in cryopreservation, utilizing the Individual Cell-based Cryo-Chip (i3C). The i3C is made of materials having appropriate durability for cryopreservation conditions. The core of this approach is an array of picowells, each picowell designed to maintain an individual cell during the severe conditions of the freezing--thawing cycle and accompanying treatments. More than 97% of cells were found to retain their position in the picowells throughout the entire freezing--thawing cycle and medium exchange. Thus the comparison between pre-freezing and post-thawing data can be achieved at an individual cell resolution. The intactness of cells undergoing slow freezing and thawing, while residing in the i3C, was found to be similar to that obtained with micro-vials. However, in a fast freezing protocol, the i3C was found to be far superior.


CONCLUSIONS
The results of the present study offer new opportunities for cryopreservation. Using the present methodology, the cryopreservation of individual identifiable cells, and their observation and retrieval, at an individual cell resolution become possible for the first time. This approach facilitates the correlation between cell characteristics before and after the freezing--thawing cycle. Thus, it is expected to significantly enhance current cryopreservation procedures for successful regenerative and reproductive medicine.
Deutsch
Mordechai
M
The Biophysical Interdisciplinary Schottenstein Center for the Research and Technology of the Cellome, Bar-Ilan University, Ramat Gan 52900, Israel. motti.jsc@gmail.com
Afrimzon
Elena
E
Namer
Yaniv
Y
Shafran
Yana
Y
Sobolev
Maria
M
Zurgil
Naomi
N
Deutsch
Assaf
A
Howitz
Steffen
S
Greuner
Martin
M
Thaele
Michael
M
Zimmermann
Heiko
H
Meiser
Ina
I
Ehrhart
Friederike
F
D002470:Cell Survival; D015925:Cryopreservation / Q000379:methods*; D005615:Freezing / Q000009:adverse effects; D006801:Humans; D044968:Regenerative Medicine; D020298:U937 Cells