An aspect of human augmentation being considered in the Symbiotic Autonomous Systems Initiative (see the first White Paper) is the possibility to re-generate organs. Our organs get older, as we get older (actually some say that we get older because our organs age…), and their performance decreases. By substituting a failing organ we can restore the performance and extend our life span. Transplant is a possibility (but you need to have a donor), 3D printing is another possibility that has become feasible for a few organs (like skin, trachea, jaw bone) but remains a matter of research for most organs (bladder, liver are next in line). The problem with both transplant and artificially printed organs is that you have to undergo surgery, remove your faulty organ and replace it with the implantable one.
Wouldn’t it be nicer if we could direct our own body to recognise the need for replacing an organ and grow a brand new one on its own?
As a matter of fact we are the living proof of the ability to develop brand new organs, all the organs we have have self developed before our birth (and the further grew into maturity). We know that some animals have the capability of regrowing parts of their body, like newts that are able to quickly regrow a fully functional limb, or the planaria flatworm that can even regrow its head! Why not us then?
In the very first stages of growth our cells have the capability to start from scratch. If in the very early process of the fertilised egg subdivision, first in two, then 4… cells all those cells are equivalent and if one is removed it will be replaced with no ill effect. These are called pluripotent cells and as the adjective indicates each has the capability to create a full blown individual.
It turns out that some animals keep aside some pluripotent cell, just in case. When a planaria loses an organ it can activate the pluripotent cell and voilà that cells starts generating the missing part.
Researchers at the Stowers Institute for Medical Research have been able to identify those pluripotent cells in a planaria and even film them as they go to work to re-generate the needed part. Use the link to take a look at the clip (it last half a hour but if you are in biology you’ll love it). This research work was carried out in 2016. Now they have managed to isolate the pluripotent cell (for detail you can read the paper published on Cell) and most importantly the method they used is based on looking for a protein (tetraspanin) that is created by a gene and ends up in the cell membrane of the pluripotent cell. The developed a marker to find out this protein and have been able to prove that cells with such a protein are indeed pluripotent cells (they have implanted the cells into a planaria that has been incapacitated through massive doses of radiation and shown that with the implanted cells the planaria re-generated its failing organs).
Now for the interesting (for us) part: it appears that this gene is also part of our human genome, and using that marker they have been able to spot the presence of the tetraspanin protein on some of our cells as well. This, according to the researchers gives hope that there may be a way to trigger the re-generation capabilities in humans as well. We are still quite far (and we do not know how far) but at least this research has opened a line of study that is concrete.
Human augmentation through re-generation is no a science fiction topic, but a difficult scientific area to explore.