@tersyne asked: I’m not sure if I’ve asked you already, but I always headcanon’d the reason they don’t use Claire’s blood to reanimate Nathan in the v4 finale is because they have incompatible blood types. What would actually happen if a person (alive or dead) was injected with an incompatible blood type from a regenerator? Could some type of compatible reanimative serum be produced a la Star Trek?
Note: this was originally posted on my blog on tumblr.com. I have tried to convert some of the formatting over, however there may be some inconsistencies. Also this particular entry was written before I knew how to cite scientific sources, so sources will either be nonexistent or incorrectly cited.
Really quickly I’m going to break down blood types and the +/- just because that’s important to answer this question. There are eight different blood types. A+, A-, B+, B-, AB+, AB-, O+, and O-. The ABO are each different antigens (little flags that identify your cells) that can be on the outside of a person’s cell. So a person’s immune system with an A blood type would not attack A antigens, but they would attack B antigens. A person’s immune system with O blood type makes a defective antigen, so they would attack any cell with an A or B antigen because this is seen as foreign. So A can accept from A and O. B can accept from B and O. AB can accept from all groups because it attacks none of the antigens. And O can only accept from O. Poor O.
Then there are the RH factors: the + and – following each ABO. RH groups code for several antigens that work together. Conveniently you either have them or you don’t. If you have them you’re RH +, and if you don’t have them you’re RH -. Someone with RH + blood can accept both + and – blood. Someone with RH – blood can accept only – blood.
Actually that isn’t quite true. Someone who is RH- can accept RH+ blood once in their life. Then their immune system builds a defense against the RH factors in the blood and the person can never accept RH+ blood again. So positive blood is only given to a negative person in extreme circumstances.
So in a normal situation if a person is given the wrong type of blood their body will attack the red blood cells. When it does this it causes the blood to clot up in the veins, which can lead to other health problems. As the transfused blood it attacked it sends out proteins that then cause the person’s kidney’s to shut down. It isn’t very pleasant.
So if the person doing the donating was a regenerator (but they weren’t O- which is the universal donor) there could be some problems. There seems to be no reason why the rengenerators blood would adapt to the new host. In fact it seems more likely that the rengenerator’s blood might be even more resilient than the recipient’s blood. If the regenerator’s ability works on a cellular level then the immune system would continue to attack the red blood cells only to exhaust the recipient’s immune system to the point of death. It could lead to internal hemorrhaging and other very nasty side effects beyond the normal kidney failure.
This could be prevented if somehow the red blood cells where cleaned, all of the antigen markers scrubbed off, and all of the antibodies in the blood washed away. However I don’t think there is any way in current medical science to do this without actually damaging the red blood cells.
The recipient, who has hypothetically had his throat slit open, could also receive artificial blood while the regenerators blood is separated out of the needed components. Artificial blood is still in the research process, so this is extremely hypothetical. Human blood carries oxygen around the body, as well as a bunch of other things (like carrying nutrients and sugar). Artificial blood is literally just a taxi for oxygen and carbon dioxide. So while the recipient is bleeding out on a hotel couch he can be pumped with artificial blood so his tissues are still oxygenated. Then while that is happening whatever is needed from the regenerators blood can be extracted so that there is no problem with rejection. Mostly likely what the recipient needs is not the red blood cells, but either platelets or white blood cells which do not have a type.
I can’t say anything about this method working on people who are already dead, since I’m pretty sure that wouldn’t work in real life. The closest thing is suspended animation, where a person that is close to death is pumped full of cold water which slows their metabolism, there for slowing their declining health long enough for surgeons to operate. Once they’re done the surgeons refill that patient with blood. Which is interesting, but not really applicable.