Throughout much of Hollywood, cryopreservation has been depicted as “deep-freezing” whole human bodies in cyrochambers, only to be easily awoken moments after the chamber has been opened. At what point is this just fantasy as compared to real-life. In today’s standards cryopreservation holds a pivotal role in preserving human tissue – such as transplant organs. However, what does it take to freeze human tissue, and is it even theoretically possible. The issue of deep-freezing human tissue does not rest on the freezing part itself, but rather the warming process that must occur to reawake the tissue cells without damaging them.
To freeze tissue cells the process must begin quickly, in order to avoid the cells from decaying further and causing irreparable harm to the organs and tissue cells. The process begins by placing the tissue on dry ice, to keep the organs or body at low temperatures. Once the organs are at a storage facility, the tissue and organs are infused with cyroprotectants, these cyroprotectants are essentially anti-freeze the prevent ice crystals from forming on the tissue and inside the organs.[1] The rationale behind this is to prevent these ice crystals from killing cells which would eventually lead to further decay and harm to the tissue and organs. The next step is that the organs must be cooled, slowly.[2] This is accomplished by cooling the tissue and organs in liquid nitrogen at a rate of one degree Celsius every hour, eventually reaching the final temperature of -130 to -196 degrees Celsius after about two weeks.[3] These low temperatures are required so that can cells survive and not dehydrate after death, because uncontrolled dehydration and freezing will cause cells to die, causing harm to the tissue and organs.[4]
The issue with deep-freezing tissue is the rewarming, or awakening of the cells. Through current warming techniques, the tissue and cells crack or crystallize during the warming process, rendering them ineffective for use during organ transplantations.[5] The British Broadcasting Corporation noted that so far there is no evidence or guarantee that technology can rewarm the cells without causing harm. However, the Scientific American journal reported that researchers discovered a technology that could rewarm large pieces of tissue without major damage.[6] This is accomplished by implanting nanoparticles evenly throughout the tissue, and when exposed to an magnetic field, begin acting as tiny heat generators.[7] This technology is just a concept so far, and needs to be refined. Nonetheless, this could be fascinating new discovery in supporting organ transplants.
As humankind continues to evolve. It is always fascinating to learn what new discoveries, or inventions have been made, whether this technology becomes reality is yet to be known. However, the evolution of this technology could spark a new generation of research and experiences not yet known to us.
[1] Philippa Roxby, What does cryopreservation do to human bodies?, British Broadcasting Corporation, November 18, 2016, http://www.bbc.com/news/health-38019392.
[2] Id.
[3] Philippa Roxby, What does cryopreservation do to human bodies?, British Broadcasting Corporation, November 18, 2016, http://www.bbc.com/news/health-38019392.; see also Rose Eveleth, Cryopreservation: ‘I freeze people to cheat death’, British Broadcasting Corporation, August 22, 2014, http://www.bbc.com/future/story/20140821-i-will-be-frozen-when-i-die.
[4] Philippa Roxby, What does cryopreservation do to human bodies?, British Broadcasting Corporation, November 18, 2016, http://www.bbc.com/news/health-38019392.
[5] Id.
[6] Andrew Joseph, New Advance May Help Organs Survive Deep Freeze, Scientific American, March 2, 2017 https://www.scientificamerican.com/article/new-advance-may-help-organs-survive-deep-freeze/.
[7] Id.