[User9821]

How long would effects like this last? I mean, let's say a bunch of children donated blood for the cause, and we used it to replace the blood of a senior citizen.

I don't know how to phrase this properly, but how long does the blood maintain the youthful qualities? Do you constantly need new blood coming in from a young donor? Do you receive it once and you're good for a week? A year?

[exratione]

Current thinking I've been privy to is that the factors in question are short-lived.

In any case, this will never turn into cross-generation blood transplants on a regular basis. The present system of medical regulation is heavily biased towards demonstrating mechanisms. If you can't explain your mechanism you are not getting approved by the FDA, or at least not until such time as everyone else in the world is already doing it and the bureaucrats are made to look bad - see the last decade of stem cell transplants for the way in which that happens.

So the attempts at therapies that result from this will likely be delivery of proteins or interference with proteins to put a thumb on the scales of metabolic machinery. At which point it lasts for the period of time in which you are getting regular injections.

[trendoid]

Most of the parabiotic procedures on mice had two organisms almost always connected to each other. Not sure if the case you described above is feasible in near future.

For eg, This one had them connected for 2 weeks : http://www.ncbi.nlm.nih.gov/pubmed/24145664

anyway, we need to wait for more research on similar methods.

[JetSpiegel]

Only one way to find out...

[User9821]

It seems like it would be relatively easy to test out. People donate blood all the time. I'm sure the effects are known of how much blood you can replace at once without causing issues. Without a doubt some elderly people would volunteer. Why can't we start giving them new blood once a week from donors, and see the results on their health or illnesses? I'm all for testing, but this seems like one of those things you could quickly move to human trials.

[tormeh]

Should be done outside the normal blood donor system. There's not that much donor blood around, so it would be unethical to use it. Not a practical problem, but it would look and feel bad.

Anyway, yes, why not try this on humans? Sounds perfectly reasonable.

[owenversteeg]

Well, many people seem to be suggesting (including the researchers themselves) that there is a possibility of the older person dying of insta-cancer after receiving the blood because their cancerous stem cells would immediately be told to start multiplying. That's why I think it's a good idea to test this in animals first.

[ars]

> There's not that much donor blood around, so it would be unethical to use it.

Lots of donated blood expires and is tossed. Make a program that all blood about to expire (1 day away) can be used for this.

[sinaa]

Because of cancer.

As mentioned in the article:

"Waking up stem cells might lead to their multiplying uncontrollably."

[phazmatis]

Scientists discover some weird thing they didn't expect, and start spitballing about what the pros/cons could be when reporters show up. News at 11.

[kiallmacinnes]

Did you read all the way to the end? Where they ended on "this will probably cause cancer" ... ?