Synthetic small molecule biological antifreezes, applications in cryopreservation

• Main Authors: Yousif, Greg, Sadraie, Sayed Iraj, Mr., Trant, John, Dr.
• Format: Text
• Language: unknown
• Published: Scholarship at UWindsor 2018
• Subjects: Antarctic; Antarc*
• Online Access: https://scholar.uwindsor.ca/uwilldiscover/2018/all2018/64

Nature uses carbohydrates for many different important roles in biological systems. Certain organisms, including Antarctic teleost fish, have evolved carbohydrates that act as antifreezes, antifreeze glycoproteins (AFGPs), helping the fish survive their sub-zero environments. The biological antifreezes act through two different mechanisms: thermal hysteresis (TH) which is the selective depression of the freezing point without changing the melting point of water (this prevents the formation of ice crystals in the hysteretic gap); and ice recrystallization inhibition (IRI), where the compounds prevent the growth of large crystals at the expense of small crystals during the thawing process. Natural AFGPs show IRI activity, and this could be useful for the cryopreservation of organs and tissue; however, they also have potent TH activity that leads to damage during freezing. These two effects must be decoupled in any useful cryopreservative, otherwise organs will be damaged as they are frozen. We have made small molecule glycolipids, far simpler analogues of the glycopeptides. These have been previously shown to exhibit equipotent IRI activity as the AFGPs, but do not exhibit any TH activity. These materials are being used by our collaborators to cryopreserve mammalian cells. Many different diseases and terminal conditions cannot be cured unless through organ replacement. The eventual goal of this project is to develop a means by which whole organs can be stored for longer durations of time allowing for increased chance of survival for people faced with debilitating health circumstances. In this presentation, the theory underlying biological antifreezes and their potential for applications in biomedicine, the synthesis of our materials, and the cryopreservative data related to our systems will be discussed.