Cryopreservation, a benchmark method to store biological materials with medical or research purposes, consists on the low temperature-induced suspension of the metabolic activity. However, exposure to low temperatures involves some impacts depending on the sample complexity. For isolated cells this impact is limited to crystal formation-related mechanical injury, whereas for tissues, embryos or organs other damages, mainly associated to the water loss, blood flow failure and the physiological response of the specimen, emerge. The ischemia-reperfusion injury, a mayor limitation factor in organs transplant and surgery that is characterized by oxidative damage, inflammation and necrosis, acts also in cryopreservation jeopardizing the specimen viability.
Thus, a quick temperature transition, preventing the generation of crystals and minimizing the lack of oxygen availability by using low toxicity biocompatible substances, is mandatory to preserve the sample viability. Facing the whole organism cryopreservation is the most complex challenge, since biological fluids must be rapidly replaced by a cryopreservation medium before the establishment of death-related processes. Furthermore, thawing should be carried out in presence of anti-inflammatory and anti-oxidant drugs preventing ischemia-reperfusion injury.
Vitrification consists on freezing a sample preserving an amorphous instead of crystal structure. This may be achieved by physical or chemical methods, but some biomolecules from organisms living in extreme weathers could represent an alternative avoiding the toxicity of the chemical antifreezes.
The aim of the research division in our organization is to develop novel technologies to protect the health status of patients subjected to cryogenic rescue during the transport, vitrification and possible future reanimation. For that purpose, Quantitative Structure to Activity Relationship (QSAR)-based approaches will be applied as theoretical basis to design bio-engeneered fusion proteins, with antifreeze and water retention activities, optimized for this particular use. These proteins, alone or in combination with anti-inflammatory and antioxidant drugs, will be tested as cryopreservation fluids in experimental models.