Survival of frozen fat body cells in an insect

Abstract

INTRACELLULAR, freezing is usually considered fatal to animal cells 1,2, whereas extracellular freezing can be tolerated if not too severe or prolonged2,3. The latter is well documented, but the former is based on negative evidence-the failure to obtain survival of cells known to have been frozen internally. Although mammalian red blood cells and spermatozoa are now commonly kept alive at very low temperatures by adding protective substances such as glycerol to the media, it is uncertain from the literature whether or not the cells themselves are frozen. Frozen mammalian tissue grafts have proved only partly viable, and it has been suggested that those cells that died may have done so because they were frozen internally4. © 1959 Nature Publishing Group.