The role of caspases in cryoinjury: caspase inhibition strongly improves the recovery of cryopreserved hematopoietic and other cells.
Cryopreserved cells and tissues are increasingly used for stem cell transplantation and tissue engineering. However, their freezing, storage, and thawing is associated with severe damage, suggesting the need for better cryopreservation methods. Here, we show that activation of caspase-3 is induced during the freeze-thaw process. Moreover, we demonstrate that prevention of caspase activation by the caspase inhibitor zVAD-fmk strongly improves the recovery and survival of several cryopreserved cell types and hematopoietic progenitor cells. A short preincubation with the caspase inhibitor after thawing also enhances the colony-forming activity of hematopoietic progenitor cells up to threefold. Furthermore, overexpression of Bcl-2, but not the blockade of the death receptor signaling, confers protection, indicating that cryoinjury-associated cell death is mediated by a Bcl-2-controlled mitochondrial pathway. Thus, our data suggest the use of zVAD-fmk as an efficient cryoprotective agent. The addition of caspase inhibitors may be an important tool for the cryopreservation of living cells and advantageous in cell transplantation, tissue engineering, and other genetic technologies.
Institute of Experimental Dermatology, University of Münster, D-48149 Münster, Germany.
Christopher
C
Stroh
Uwe
U
Cassens
Ajoy  K
A
Samraj
Walter
W
Sibrowski
Klaus
K
Schulze-Osthoff
Marek
M
Los
D000590:Amino Acid Chloromethyl Ketones / Q000494:pharmacology*; D000818:Animals; D053148:Caspase 3; D061945:Caspase Inhibitors; D020169:Caspases / Q000502:physiology; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D015925:Cryopreservation / Q000379:methods*; D015853:Cysteine Proteinase Inhibitors / Q000494:pharmacology*; D005615:Freezing; D006367:HeLa Cells; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000187:drug effects; D006801:Humans; D019169:Jurkat Cells
D000590:Amino Acid Chloromethyl Ketones; D061945:Caspase Inhibitors; D015853:Cysteine Proteinase Inhibitors; C096713:benzyloxycarbonylvalyl-alanyl-aspartyl fluoromethyl ketone; C505407:CASP3 protein, human; D053148:Caspase 3; D020169:Caspases