C-1001: Small molecule inhibitors of ice recrystallization – From design to mechanism of action and applications

Abstract

Ice recrystallization has been identified as a significant contributor to cellular injury and death during cryopreservation. Unfortunately, many cryopreservation protocols are suboptimal. Thus, interest has arisen in designing novel ice recrystallization inhibitors and using these moleclues as cryoprotectants. Recently, our laboratory has reported several classes of small molecules that have the ability to inhibit ice recrystallization. These classes include amino acid-based organogelators, non-ionic carbohydrate-based amphiphiles (aryl and alkyl alditols) and O-linked alkyl and aryl glycoside derivatives. We have conducted comprehensive structure function studies to optimize the ability of these molecules to inhibit ice recrystallization and also facilitate a more thorough understanding of their mechanism of action. These studies have revealed that long alkyl chains or substituted aryl groups that add “hydrophobicity” to the molecule are essentail for potent inhibition of ice recrystallization and that the relative position of these groups is important. In addition, the choice of counterion can have a dramatic effect on the ability of these compounds to inhibit ice recrystallization. Collectively, our results suggest that a high degree of hydration of these small molecules (and their counterions where appropriate) is a prerequisite for a potent inhibitor of ice recrystallization.?A number of these small molecules described above have been investigated as cryoprotectants and have been found to freeze human red blood cells (RBCs) using low amounts of glycerol. Deglycerolization studies and analysis of RBC recoveries have revealed important insights in the mechanism of action of these small molecule ice recrystallization inhibitors.