Can Human Organ Cryopreservation transform medicine the way refrigeration transformed the food industry?
Organ donation is a vital part of the various life-saving services that modern medicine offers. Medical science is at a stage today where we can successfully transplant various organs of the human body from one person to another with minimum risk. Everything right from the Cornea of the eye, to the valves of the heart to the calf-tendons from the legs can be donated. Around a million people are on the waiting list for an organ transplant at this moment, and only a fraction of them will go on to receive an organ from a suitable donor. In USA alone, a country known for its splendid healthcare services, only 15-20% of the people on the waiting lists ever receive a suitable organ.
Human organs have a very short shelf-life after being extracted from a person’s body. In most cases, the transplant needs to be completed within a day or two before the organ decomposes or becomes ineffective. This means that there needs to be an efficient system in place for identifying the potential donors and recipients of organs. Organ-donation needs vitals like blood group and rhesus factors of both the donor and the recipients to be matched in advance. Such constraints make organ donation difficult, uncertain and expensive.
Nature has several mechanisms that can inspire the development of methods and products that can take medical sciences to the next level. When about the storage of organs, scientists have looked to the North-American Wood Frog.
The Wood Frog’s characteristics are just like any other frog, except it has a different way of tackling the cold winters. While most frogs hide themselves into deep pits and hibernate for long durations during winters, the Wood frog instead seeks cover under leaves near the surface, where it freezes itself along with the surroundings. During this period it can make no movements and all body processes, including beating of the heart stay suspended! After the long northern winters are over, the frog de-freezes itself and all body functions return to normal. This is made possible by the presence of anti-freeze like properties present in their blood. While the water part of blood freezes, the plasma part does not. Read More: National Geographic-Antifreeze Like Blood
Drawing inspiration from the Wood Frog, Scientists have been experimenting with ways to store human organs at sub-zero temperatures. This process if successful can potentially solve the many challenges related to organ donation. Cryopreservation (storing at temperatures below zero) of organs, is still in its early stages of development and research. Medical scientists have been trying to develop this technique for over five decades. Initially, scientists experimented with human cells and tissues mixed with salt-solutions. These cells were then stored at temperatures as low as minus 28 degree celsius. Today, they have come as far as preserving animal veins and kidneys over short periods and at very low temperatures. A California-based cryopreservation research company, made a significant breakthrough: they vitrified a rabbit kidney, keeping it below the glass transition temperature of -122°C for 10 minutes. This is the closest that scientists have come to succeeding.
The future of success in Cryopreservation of organs lies in the synthesis of better fluid-solutions that can keep the freezing point of cells and tissues low, while causing no harm to the tissue-structures themselves.
Although we are far from a day when we will be able to store organs for long durations, developments in Cryogenic preservation technology bring much hope for the millions of people who require organ transplants each year.