The preservation of singular cells has been possible for quite some time. In science, we regularly freeze bacterial cells in the laboratory for long-term storage (at -80oC with some sort of ‘biological’ anti-freeze, like glycerol). In medicine, the freezing of human cells, such as bone marrow, blood and reproductive cells is common practice. However, our fascination with life after death and the advances in technology has led to the idea of freezing entire human bodies – with the hope to someday revive them.
There are companies specializing in the cryopreservation of human bodies, such as Alcor (REF 1). Members of these companies are placed on a ‘watch-list’ and when their time draws near, a medical team is on stand-by to swoop up your body (or brain) when you are declared legally dead. It is preferable to get your body into deep freeze (-196oC) as quickly as possible to lessen the effect of bodily decay. They pump your body full of a cocktail of chemicals to preserve the tissue and prevent ice crystals forming inside the cells (termed cryoprotectant perfusion). Your body is cooled gradually to prevent thermal stress and fracturing. You can read about the entire procedure on Alcor’s website, including a cryopreservation protocol with a step-by-step explanation. As you can imagine this service is also very expensive.
The idea behind such a service is that you would freeze your body with the hopes that future technological/biological advances would be able to revive you. It’s the fountain of youth principle in a quest for immortal life… It might sound a bit like science fiction, but there are several cases of freezing and successful resuscitation in the animal kingdom. For example in:
- Insects and Invertebrates: Freeze-tolerance has been extensively studied in insects and invertebrates, such as nematodes (Panagrolaimus davidi), inter-tidal molluscs and earthworms. These species rely on build-in cryoprotectants to ensure cellular integrity (REF 2).
- Amphibians and Lizards: The Wood Frog, Rana sylvatica synonymous Lithobates sylvaticus, is a freeze-tolerant frog inhabiting areas in Canada, Alaska and the Arctic Circle. Unlike some invertebrates that require ice-nucleation proteins in their haemolymph, the wood frog has gut bacteria that act as cryoprotectants (along with glucose). (REF 3)
However, there are several limitations to the freezing of living animals (Table 1):
- Generally, the body of the organism needs to be frozen gradually and the larger the animal, the longer the freezing process. Few organisms can tolerate sudden/snap freezing (REF 2 & 3).
- Few animals can withstand extremely low freezing temperatures, the general limit sits at ~ -2oC, whereas the nematode (P. davidi) has been recorded to survive up to -80oC (REF 2).
- No organisms can tolerate whole-body freezing, about 50-75% of the body can be frozen at once depending on its size (the larger the organism, a lesser percentage) (REF 2 & 3).
- Finally, no living organisms can be frozen indefinitely (the wood frog can go for up to 4 weeks in a semi-frozen state) (REF 2 & 3)
These limitations are imposed due to the fact that the animals are still alive when frozen. Metabolic processes within the cells do not cease, they just slow down tremendously. These active cells still require oxygen and the expulsion of waste products. When possible, freeze-tolerant animals will increase their metabolism and/or temporarily awaken to flush out toxins. Also, due to the fragile state of the organisms during freezing, they are susceptible to freeze – and mechanical cellular damage. This is one of the reasons why you should remove your E. coli cells from deep freeze storage, re-grow them and then re-freeze them again. However, organismal revival is possible due to the fact that the organisms were alive before undergoing cryopreservation. Thus, I wonder how exactly one would ‘revive’ a dead body?
I am going to touch upon some macabre topics of bodily decay and putrefaction, but don’t worry I am not going go all CSI with the gory details! As with living cells, which do not cease to be metabolically active, dead cells do not cease undergoing decay. Bodily putrefaction is mainly driven by the gut bacteria in the human body. Hence, why the Ancient Egyptians removed body organs, packed the cavity with sand bags and placed the individually preserved organs in pots, separate from the preserved body, in the sarcophagus. They believed that the deceased person’s soul would still require their body and organs once they reached the afterlife (but apparently the organs needn’t be in the body!). This leads me to the next question(s), if the body has died and you can somehow revive it – would the ‘consciousness’ and/or ‘soul’ of the person still be there?
Maybe you would be able to get the body functioning again, but would the person still remain? I mean it’s all fine and dandy to pay away your future earnings, retirement fund and/or children’s inheritance for a life-extension service – it is your business after all… but what if you are not preserved along with your body? I know that some people think that we as a persona are merely electrical signals firing in the brain and that neuropreservation should cover that, but if we are so susceptible to damage while frozen – it is not impossible to predict that you too would be damaged somehow during the process. Also, where did you go or what did you do while you were waiting for your body to reanimate again? Would you simply perceive the process as a very long period of sleep? Or even be trapped in those ‘near-death’ experiences, either good or bad? Would you be able to adapt to the ‘new futuristic world’ once you wake up? Would the futuristic people even want to or allow you to be resurrected? This is what I wonder about when I see these types of services advertised or when they are featured during TV detective stories. These questions would also be especially important if you believe that there is more to life than just our present worldly human experience, or if you at least can acknowledge that we cannot definitively know or not know…
Thus, the preservation of the dead to ensure life for the future would require far more than just fancy science when you go against the tendencies of nature, because preservation of the soul would require a lot more creativity. Therefore, cryopreservation rather becomes more of an Art form than simply pure Science when you take into account the Nature of what it means to be human.
- Alcor: Life Extension Website
- David A. Wharton (2012). Supercooling and Freezing Tolerant Animals, Supercooling, Prof. Peter Wilson (Ed.), ISBN: 978-953-51-0113-0, InTech, Available from: http://www.intechopen.com/books/supercooling/supercooling-and-freezing-tolerant-animals
- Wood Frog Freezing Survival, Maimi University, Department of Zoology