A molecular basis of cryopreservation failure and its modulation to improve cell survival

The requirement for more effective cryopreservation (CP) methodologies in s upport of the emerging fields of cell bioprocessing and cell therapy is now critical. Current CP strategies appropriately focus on minimizing the dama ging actions of physicochemical stressors and membrane disruption associate d with extra- and intracellular ice formation that occurs during the freeze -thaw process. CP protocols derived from this conceptual paradigm, however, yield suboptimal survival rates. We now provide the first report on the id entification of delayed-onset cell death following CP and the significance of modulating molecular biological aspects of the cellular responses (apopt osis) to low temperature as an essential component to improve postthaw outc ome. In this study we quantitatively examined the molecular basis of cell d eath associated with CP failure in a canine renal cell model. In addition, we report on the significant improvement in CP outcome through the modulati on of these molecular mechanisms by the utilization of an organ preservatio n solution, HypoThermosol (R). Further, the utilization of HypoThermosol (R ) as the preservation medium and the modulation of molecular-based cell dea th have led to a paradigm shift in biologic preservation methodologies. The recognition of molecular mechanisms associated with CP-induced cell death offers the promise of improved CP of more complex and/or fragile biological systems such as stem cells, engineered tissues, and human organs.