The instances of clinical storage of cord blood have increase manifold in the recent years, and it is said that the number of units stored is in excess of 70,000 throughout the world. India is also a fast growing destination for the Stem Cells cryopreservation fraternity. Many regional processing centers have been set up to process the collected cord blood samples. Often there is considerable distance between the collection centers and regional processing centers which necessitates the development of short term as well as long term storage processes for the stem cells derived from the umbilical cord blood.

The initial work on the theory of cryopreservation was done by James Lovelock who suggested that the damage to the red blood cells was being caused due to osmosis stress.

The Downsides

In the cryopreservation process, the stem cells collected from umbilical cord blood samples, are frozen to sub zero temperatures. The cryopreservation process comes with many risks. The solution concentration has to be correct otherwise the stem cells being preserved may be damaged. Also, if the tissue cooling process takes place slowly, the water within the tissues goes out of the tissues thus forming ice in the extracellular space. This ice may damage the cell membranes mechanically due to crushing. The water migration from the cell may also result in cellular dehydration, which again can damage the cells.

How to Avoid the Downsides?

Machines are used to freeze the stem cells in programmable steps before putting them into the deep freeze stage in liquid nitrogen. The technique of Vitrification, on the other hand, claims to cryopreserve the samples while negating the damaging effects of ice crystal formation. The technique uses cryoprotectants before the cooling process, which increases the viscosity. The process also ensures that the solution doesn’t crystallize and turns into amorphous ice. The same effect can be produced through rapid cooling of water without using the cryoprotectants.