DARPA Sponsoring Limb Regeneration Research

fragmentate writes "Wired News is reporting: 'In response to the hundreds of soldiers coming home from war with missing arms or legs, Darpa is spending millions of dollars to help scientists learn how people might one day regenerate their own limbs. Prosthetics are getting better all the time, but they will never be as good as the limbs we were born with. So two teams of scientists at 10 institutions across the country are competing to regrow the first mammalian limb ... The researchers' first milestone is to generate a blastema — a mass of cells able to develop into various organs or body parts — in a mammal.' Apparently this is a relatively new area of research, even Wikipedia's stub on blastemas is very terse."

Stub.

[Wordsmith]

Wikipedia's stub. I get it. Hah.

Re:Stub.

[Darkman, Walkin Dude]

Jokes aside, if they can regenerate limbs, surely its just a hop skip and a jump to regenerate organs? If we can do that, immortality is just around the corner...

Re:Stub.

[Stile 65]

First of all, TFA says that one of the two teams of scientists working on this is basing their work on the MRL mouse, which can and does regenerate internal organs, including severed spinal cords.

Second of all, this may increase lifespan, but would not provide immortality. Human cells stop reproducing after a certain number of reproductions. The cell chromosomes have end-cap like things called telomeres which are shortened with each mitotic cycle. When they get too short, the cell stops reproducing. This is to prevent too many mutations from accumulating after a while. Generally, if cells divide without shortening the telomeres, they're usually malignant tumor cells. So to get immortality, you'd have to augment the mitotic cycle to a) "spellcheck" the chromosome copying, and b) prevent the telomeres from being shortened.

Re:

[Flavio]

The chromosome copying is already spellchecked.

Both prokaryotic and eukaryotic cells have copy verification and repair machinery which drastically reduce replication errors.

Re:Stub.

[izomiac]

Drastically reduce but not eliminate. IIRC mutations tend to occur once every 600,000 base pairs, so that would mean that replication is about 99.99983% accurate. After 100 divisions the genome of a cell would only be 99.983% accurate, so it'd have about 1 error every 500 base pairs. Given the size of most genes/proteins, that cell should have some serious problems or be cancerous. (I don't know the "maximum" number of divisions, it could be more or less, but you can see the problem.) Not to mention, mutation accumulation is just one part of aging. Now, if we could take our genome and add some parity base pairs and some redundancy checking proteins we might be able to address that problem. But that's far beyond our level of genetic engineering (AFAIK).

Re:

[sabernet]

I'm sorry, but I gotta say it. This thread you two got going is the coolest thing I've read on slashdot in a while.

Carry on:)

Re:

[QuantumG]

The actual engineering involved isn't that important. What's important is that researchers no longer consider aging to be just something we have to live with, and consider it their goal to increase the human lifespan. Note, this isn't all researchers. Many people still believe that humans should always grow old and die and to perform research into indefinitely extending human lifetimes is wrong.

Re:Stub.

[mrogers]

If a person lives for 1000 years and their personality continues to evolve, to what extent can the 1000-year-old individual be regarded as "the same person" as, say, the 30-year-old individual? Are you the same person you were 10 years ago, or 20? What would 1000 years of experience, combined with 1000 years of cultural, political and technological change, do to the human personality?

Re:Stub.

[javilon]

a) "spellcheck" the chromosome copying, and b) prevent the telomeres

b) is easy, you can shut off telomerase for a while(http://www.pubmedcentral.nih.gov/articlerend er.fcgi?artid=14711&tools=bot [nih.gov])

Re:

[Stile 65]

You're exactly right.

They do have controlled drugs in development (two that I know of off the top of my head) that can temporarily increase telomerase activity. I don't know how well targeted they are, though, and to me that's important, because in my mind, if you have a precancerous cell and you turn up telomerase activity then WHAM, you've just triggered a malignancy.

Re:

[Anonymous Coward]

Actually, humans have an enzyme called telomerase [wikipedia.org] that rebuilds telomers. You're right that telomers do wear down over time, but the solution may be much simpler than preventing telomer shortening, which, if I remember correctly, is sort of a side-effect of DNA replication.

Re:

[Stile 65]

Telomerase is hyperactive in over 90% of cancer cells... thus the point in my original post that it's linked to malignant tumors. :P

Re:

[rolfwind]

If they can regenerate organs, will they be able to regenerate the largest organ, skin? This would help burn victims immeasurably.

Re:

[Firethorn]

From what I've heard, they can pretty much clone skin now. The problems now are grafting it and growing enough of it fast enough.

They can culture skin artificially, as well as use various mechanical methods to 'stretch it'.

Re:

[RobinH]

As I understand it, the ability of cells in a human body to regenerate themselves (heal) diminishes over time due to "programming" in our genes. This causes aging, but is also a cancer fighting mechanism.

If you could use a given adult's body to grow a blastema or whatever it is and then use it to grow a limb or organ, the cells would remember their "age" and would still not be as resilient as a child's organ or limb. Therefore, you could replace your heart at the age of 75 but it would still be a 75 year

Re:

[lawpoop]

Well, considering that a limb is made up of serveral organs, such as bones and muscles, I would think that you would have to get organs before you could get limbs.

Re:

[brainburger]

hmmm - I bet it is possible to regenerate the body indefinitely, (eventually), but I am doubtful that this is possible with the mind. Even if the brain-tissue could be replaced, could a useful structure be preserved? How would a human mind cope with the increased memory requirements? - It would distort the psychology somewhat to have centuries or millennia of experience.
Perhaps the brain could drop its oldest memories in favour of new ones, but would this seem like immortality to mind of that person?

worthy of King Midas

[Original Replica]

Immortality may be just not that far off, but all that would lead to is an increase in over population and wealth stratifacation. I'm all for improving the quality of life for amputees but I think a century or so is long enough for any one person.

Re:

[catbutt]

Well, from a Malthusian perspective, the population is always going to increase to capacity regardless. Personally I think it is a separate problem.

Re:

[LurkerXXX]

I don't know about that. In modern industrialized nations with good education and economies, the average population growth is negative (if you don't count immigration). If we can get all the 3rd world countries up to speed with economy and education, we might not have an over population problem.

Re:

[RyuuzakiTetsuya]

What about when this gets duped?

Wikipedia

[the linux geek]

Since this is Slashdot, which is not exactly known to be a bastion of maturity, I bet that Wikipedia won't be very terse for long...

Re:

[iggymanz]

it's the spammers I fear: get your Penis Enlargement Blastima now!

Re:

[nametaken]

Funny, that was my thought, except I had a bit more optimistic expectation. I was hoping that it would get filled out in record time with quality info. :)

Reminds me of The Forever War

[bhunachchicken]

(WARNING - SPOILERS)

When William Mandella lost his leg in an accident he was under the impression that he would simply be given an artificial one and would then be free to persue a semi-normal life. To his horror he discovers they'll simply grow him a new leg and chuck him right back in to active duty... :)

Re:Reminds me of The Forever War

[nosredna]

New moderation ideas are a dime a dozen, but I have to throw one in for this...

+1 Creepy but probably true

Re:

[operagost]

FWIW, in the U.S. military you are given an honorable discharge on demand if wounded three times (three purple hearts), so even if something ridiculous like this happened you'd be sent home by the third severed limb :-P

Re:

[Dorceon]

I expect a stop-loss policy would trash that rule PDQ.

Re:

[Firethorn]

I expect a stop-loss policy would trash that rule PDQ.

Why? They had the policy during wartime when they were busily drafting people.

Oh, and it's not three PH's and you're able to get out, it's three PH's and you have the option of transfering to a non-combat area.

I imagine that regrowing a limb and retraining you on the usage of it would be something that'll take years. The nerve endings are never quite the same...

Oh, and you'll never really get combat troops until you realize that there have been documen

Not too far from reality

[EmbeddedJanitor]

IIRC, it makes a good story anyway, the use of pinning etc was pioneered by military medics as a way to quickly heal limbs and recycle soldiers faster. Previous to that, an "accidentally" damaged leg was a ticket back to home comforts and safety.

Has no one seen the Spider-man cartoons

[JoeyJoeJo]

Wasn't the Lizard created from a scientist who was trying to do this very thing?

Don't underestimate prosthetics

[Chandon Seldon]

Prosthetics are getting better all the time, but they will never be as good as the limbs we were born with.

Why not? I see no good reason why competent engineering can't eventually beat a chunk of meat.

It's not like we were intelligently designed... we evolved. Evolution will tend to produce good solutions to problems, but it will hardly ever produce the best possible solution. Once we get nerve-circuit interfaces down, we should have no problem outengineering most of the human body.

Re:

[imsabbel]

In 2 or 3 centuries maybe.

Sure, the human body is a result of evolution, but that doesnt mean that its not sophisticated at all. Its the result of a billion years of "everything thats not good enough died", starting from the level of cellular chemistry up to the general layout.

Re:

[Chandon Seldon]

In 2 or 3 centuries maybe.

Oh, I think we can do better than that. Remember that "everything that's not good enough dies" combines with "anything that's better than it needs to be gets pwned by random mutations".

Re:Don't underestimate prosthetics

[Darkman, Walkin Dude]

we should have no problem outengineering most of the human body.

Yes and then the batteries in your cyberleg run down and you have to haul the entire 40 kilo hunk of metal across town in the rain... on one leg. Besides that you are forgetting that the limbs aren't seperate components of the body; its all interlinked. Its no good having an arm able to flip over a truck, your torso would compact and tear itself apart if you didn't just rip the thing off, nerve circuits and all. The only real option for enhanced performance cybernetics would be a Ghost in the Shell effort, with full body replacement except for the brain. If you can manage that, without regular maintenance and some sort of 50 year power source, I'll admit you have a point.

Re:Don't underestimate prosthetics

[Chandon Seldon]

Consider that cyberleg. We can build it to run off glucose in order to avoid it running out of batteries. We can easily give it the performance characteristics of an athlete - we know the human body can take that. It will never get out of shape. Assuming it has sufficient glucose (which is easy to introduce to your body, especially if you deal with the insulin thing right), it will never get tired.

Now, that's no car-tossing cyberarm, but it's definately an improvement on the stock equipment. The downside is maintnence, but anyone who's paid too much attention to cyberpunk settings knows that - and that can be reduced with better engineering.

Re:

[metlin]

Good point.

Not to mention layers and layers of redundancy, of course -- if something goes wrong, our body can easily adapt and on occasion, rewire the synapses.

A synthetic body should be capable of the same thing, too.

Re:

[Khyber]

Odds are neural wetware will run off of the natural electrical curent your body produces, or can be easily recharged thru an inductance field (though this means the charging pack is close to the skin.) We're working on this already with devices implanted into your spine that overload your spine with "information" so you don't feel pain nearly as much, for those with irrepairable spinal injuries. You might want to read a book titled "Cobra" as it somewhat touches on this topic, though more in a military man

Re:Don't underestimate prosthetics

[daeg]

Just because we may eventually out-tnature doesn't mean the thousands of injured soliders and civilians want part of their body replaced with robotics if they could have the option of a new, real limb.

There is also no reason both areas of research can't operate simultaneously, nor anything that is restricting them from working coopoeratively.

Re:

[Chandon Seldon]

You are absolutely correct.

It just annoys me when people assume that technology isn't going to improve, or that the human body is the pinnacle of perfection.

Re:

[Britz]

I get your point, but:

1. It will take a while! I think it is more a matter of centuries than decades.

2. It will be too expensive for most people. Look at the moon landings. They would never have happened if not the richest nation on earth would have poured so much money into it. Even now it is still too expensive to put people into near orbit. The few exeptions only go there, because the governments still spend A LOT of money on it. The few tourists (that still pay more than some thousand people in Africa s

Re:

[WhiplashII]

So they actually travel on huge subsidies.

Actually, this is probably not the accurate way to look at it. The only government flying paying space travelers is doing so after bankruptcy essentially - and it is typical for an after-bankruptcy bussiness to sell close to marginal cost.

Sunk costs, and all that... trust me, the former soviets are not flying rich Americans with a government subsidy!

Re:

[drsquare]

Your own limbs have grown and developed based on how you use them and look after them: bone density, nerve wirings etc. A limb grown in the lab won't have developed the same so won't be suitable.

Re:

[lawpoop]

Isn't anything we design thereby a product of evolution? If evolution produced the human brain, which in turn produced a prosthetic limb, isn't it evolution which ultimately created the limb?

Re:

[Chandon Seldon]

No. For a given organism, evolution only cares about two outcomes: death and reproduction. Anything the organism does that doesn't result in its genes being preserved has nothing to do with evolution.

Re:

[Quadraginta]

Evolution will tend to produce good solutions to problems, but it will hardly ever produce the best possible solution.

Not so. Unless the space of solutions is extremely unusual -- not simply connected, something like that -- natural selection will always find the optimum solution, given enough time. Deliberate engineering gets you to the optimum faster, that's all. But natural selection has got one hell of a head start on deliberate engineering as far as our bodies go, like maybe four million years' wort

Re:

[TrappedByMyself]

but it will hardly ever produce the best possible solution.

So.... the human brain which isn't the best possbile solution because of evolution, will produce the best possible solution?

Re:

[Chandon Seldon]

That's the neat thing about evolving sentience... yes.

Re:Don't underestimate prosthetics

[Darkman, Walkin Dude]

That's a bold statement of fact, considering even the most avid proponents of evolution refer to it as "theory".

Not a great troll... poignant, with a hint of maple... but lacking in the body and depth that a really rich, warm troll should have... I'll have to give this one star, I'm afraid.

Re:

[Conspiracy_Of_Doves]

Evolution is both theory and fact. Please learn the definition of the word 'theory'.

Re:

[cappadocius]

Evolution is both theory and fact. Please learn the definition of the word 'theory'.

To be fair to the little troll, the original post clearly is referring to the theory of evolution.

The fact of evolution does not make predictions about the degree to which the design of any biological organism is optimized. All scientific theories of evolution derived from the Darwinian one seem implicitly to do so.

Re:

[Chandon Seldon]

even the most avid proponents of evolution refer to it as "theory".

Yup. Like the theory of gravity.

There's no question that organisms evolve any more than there is question that masses attract eachother. There is some debate about the exact mechanism for these effects, but there's no question that they happen.

Re:

[Chandon Seldon]

Arrogance is a virtue. Without it, we would give up without even trying.

That's not to say that you're not right. We have a ton of stuff to learn from biological systems - we've barely begun to scratch the surface on all the useful stuff that evolution has come up with.

Re:

[Chandon Seldon]

What, exactly, do you mean by "versitility" and "adaptability"? Give examples.

Outengineering a biological system isn't nessisarily easy, but I assure you that it's possible. High tech devices aren't always better, but they frequently are - which is why we build them.

Wikipedia's stub on blastemas is very terse

[Anonymous Coward]

I think it would be more accurate to say Wikipedia's stub on blastemas is embryonic.

is this really the right reason?

[macadamia_harold]

In response to the hundreds of soldiers coming home from war with missing arms or legs, Darpa is spending millions of dollars to help scientists learn how people might one day regenerate their own limbs.

You *know* the Army's thinking behind this is to regenerate their limbs so they can just send them back to war.

Re:

[Dravik]

What all the people who post this seem to miss is that most of the soliders want to get back to the front and help their buddies. This isn't some evil army destroying soliders. They generally want it as much or more than the Army.

can we grow some extra limbs in advance?

[porky_pig_jr]

so, say, if one hand is blown off, I still have a few more left, no need to rush to hospital. an extra head won't hurt either. (with a possibility of starring in Hitchhiker).

just grow a spare parts clone

[Quadraginta]

The serious issue your joke illuminates is the possibility of people growing a clone for the purpose of "spare parts." No risk of rejection when you do the transplantation, see?

Re:

[DoubleRing]

You really should read Nancy Farmer's The House of the Scorpion [amazon.com]. It's all about growing clones for transplants. It even talks about drug lords and even has a less than savory solution to the US's illegal immigrant problem! All for only $12.21!

In all honesty, it's a good book. Go check it out at the library. I commmand you!

Potential for other applications

[Anonymous Coward]

If they can give soldiers the ability to grow amputated limbs, any possibility this technology can be used to produce 100% real enlarged breasts? Forget silicone and saline implants, in ten years time we'll have women who can inject themselves with this serum and grow from a B-cup to DD. I imagine the government will find a way to outlaw that, too, just like they did for silicone "for the saftey of women".

Re:

[kfg]

If they can give soldiers the ability to grow amputated limbs, any possibility this technology can be used to produce 100% real enlarged breasts?

Yes, but don't be surprised if people look at you funny -- or maybe that should be funnier.

KFG

Re:

[ErikZ]

Not really. Regenerating a limb is replacing something your body already has instructions on how to build. Since the B-cup girl doesn't have the instructions for a DD, it wouldn't work.

But it would rock for those who had a mastectomy.

Re:

[lawpoop]

My bet is what will happen first is that scientists will be able to generate the larger breast organ in the lab, and start surgically implanting those instead of the silicone or saline. I think it's a harder trick to get the new breat tissue growing in exactly the right places.

I sense a disturbance in the Force

[GungaDan]

as if a million stumpfuckers suddenly cried out in protest.

One step closer...

[QuantumFTL]

This is one step closer to the invincible zombie army that the government is working on. Maybe it will help us defeat the robots in the future?

Why yes, my hat ismade out of tin. How did you know?

Re:

[QuantumFTL]

We know all about you QuantunFTL (the tinfoil, it does nothing)

It's apparently blocked you from reading my nick properly... :)

Millions ?

[OpenSourced]

The two groups are sharing $7.6 million in grants for a year to find a way to give humans salamander-like abilities.

Am I out of whack or it's $7.6m like peanuts for this kind of research? I'd guess any serious effort on that would need to be in the billions level, and that likely for many years.

You don't have to build accelerators or reactors

[Beryllium Sphere(tm)]

This is the sort of science that can be done without huge capital costs. A few million dollars will go a long way when spent on salaries and salamanders.

Re:

[Quadraginta]

Eh...I'd have to disagree with that. What's important to realize is that science is, by and large, a process of finding what works by systematically trying everything that doesn't work first. That's one reason it's enormously expensive and takes so much time.

In hindsight you can often recognize the tender little shoot of the Right Idea growing, and, yes, it is often growing in some neglected garden with very little fertilizer (a.k.a. money). You'd naturally think that "all" you have to do to be much more

Re:

[Quadraginta]

Ha. And I say that as a theoretician.

How about some hair regeneration?

[glrotate]

Let's focus our efforts on something a little more important.

Thanks.

Re:

[east coast]

Go read your Polya.... Hair regeneration is simple and, I'd like to think, something we learned from doing something small and simple first helped us understand the larger puzzle.

Re:

[Dorceon]

Hey, they already have spray-on hair. Why not spray on limbs? Doing some work on a precarious perch? Spray on a few extra legs for balance, and amputate them when you're done.

further info

[EricBoyd]

some more info for anyone interested:

Timelines for Manipulating and Greatly Enhancing Human Regeneration
http://www.fightaging.org/archives/000929.php [fightaging.org]

Transhumanism: Regenerative Medicine
http://digitalcrusader.ca/archives/2006/05/regener ative_me.html [digitalcrusader.ca]

recall the transhumanist point of view

[khallow]

Dismissing prosthetics as being less than natural ignores that the technology is always improving. It's not that hard to envision a time when the prosthetic limb is better than the natural one. For example, at best, we'll be able to grow back a natural limb. If a prosthetic limb breaks, it will probably be a lot easier to replace. OTOH, it's reasonable to assume that a considerable fraction of people are going to want like replaced with like. Ie, they will often want a natural limb replaced by a natural one

Potential for new cybernetic prosthetics

[Colgate2003]

they will never be as good as the limbs we were born with

Not quite as good, but I just interviewed [mos.org] someone about new research into interfacing neurons with electronics that could lead to Luke Skywalker-like replacement limbs. Harvard researchers have figured out a way to directly read and write to a neuron with digital electronics.

Re:

[thrillseeker]

Harvard researchers have figured out a way to directly read and write to a neuron with digital electronics.

It gives new meaning to the BSOD.

Akira...

[MaineCoon]

The researchers' first milestone is to generate a blastema -- a mass of cells able to develop into various organs or body parts -- in a mammal.

Cue out-of-control flesh monster, Akira-style.

Been done in rats

[nurb432]

Look up 'charles becker', he did things like this in his research 20 years ago. Was regrowing rat legs right and left from what i remember.

And isnt a rat pretty close to a human? Thats what they keep saying anyway.

Talk about going for cheap karma points

[Infonaut]

Only if he's a lawyer.

In the same vein, all engineers are nerds who can't get a date. All designers are homosexuals. All male programmers are socially inept, and there are no female programmers. All doctors have a God Complex. All firefighters, of course, are heroes ;-) .

Prosthetics beat natural limbs

[r00t]

6 million dollar man
Inspector Gadget
Luke Skywalker

Fake limbs can resist bullets. They can have powerful weapons and other tools. If you buy the Dr. Strangelove model, you get to blame the arm's buggy software when it grabs a woman's butt.

Re:

[PakProtector]

Until the control is good enough that I can, say, play guitar without any more difficulty than I do with my meat hand, I think I'll stick with meat.

Time for the new DARPA challenge!

[JoeCommodore]

A member of each tem gets one limb sawn off and the first one to regrow it to appropriate size wins the prize!

so about the guy who got the penis transplant....

[Nocturnal Deviant]

now he wont have to look down and see another mans penis lol

"So it'll just grow back then, will it?"

[toby]

Perkins: Bitten sir. During the night.
Ainsworth: Hm. Whole leg gone eh?
Perkins: Yes.
[As they talk, the din of battle continues outside. Screams of dying men, crackling of tents set on fire.]
Ainsworth: How's it feel?
Perkins: Stings a bit.
Ainsworth: Mmm. Well it would, wouldn't it. That's quite a bite you've got there you know.
Perkins: Yes, real beauty isn't it?
All: Yes.
Ainsworth: Any idea how it happened?
Perkins: None at all. Complete mystery to me. Woke up just n

MILLIONS? Surely Not.

[shaneh0]

DARPA is spending MILLIONS to help researchers re-grow limbs. Try that again. They're spending MILLIONS (which is what you need for a fair retirement) to advance the RE-GROWTH OF A HUMAN LIMB. In other news, I'm donating $12.32 towards the advancement of Sentinent AI. By my estimates, my $12 will yield results in 2 or 3 hundred years. Shortly thereafter my AIbot will then invent a way to regrow human limbs, beating the underfunded DARPA project by 3 or 4 hundred years.

I'm way ahead of them

[beeblebrox]

what the subject said.

Why?

[HermanAB]

The traditional solution is to grow completely new soldiers as gun fodder - these are generally called babies. I don't see the strategic advantage in growing only partial soldiers, unless one can do it very quickly and get say a 14 day turn around on a limb, which could be better than the current 18 year production cycle...

Blastemas and Anime

[deek]

Now finally, we can name the effect used in anime, when they do near-instant limb regeneration. You know what I'm talking about ... that bubbly organic extrusion that happens when chopped off limbs are regenerated. This shall now be called a "Blastema". Also used when organic bodies are psychically mutated, as in Akira.

Re:

[kahei]

I'm sure that's already occurred to DARPA. Unfortunately, the military goes off to Iraq when they are ordered to by the elected representative of you, the voter. So what are you doing about it?

Re:

[Stormwatch]

Heinlein, is that you?!

Re:

[PakProtector]

Yes.

Re:Radical idea

[Original Replica]

... or maybe only PeaceCorp veterans ...

Re:

[MightyYar]

Thank you, Captain Obvious. Now let the grown-ups talk.

Re:

[c_forq]

We tried that one for a while. We were criticised for being xenophobic and isolationist.

Re:

[WhiplashII]

More to the point, if you look at the real complaint the terrorists have, it is cultural invasion. But we don't even do the cultural invasion: We are merely successful. That makes people is other countries emulated us - in general raising their success level. But they are seen as traitors to the original culture, and as selling out to the US. (You can also see this happen inside the US in various social groups to a more limited extent.)

So, without us doing anything except minding our own business and s

not Washington

[Quadraginta]

You probably want to address Madison or Jefferson, not Washington.

Re:

[Quadraginta]

Or perhaps the nation has a much greater duty to help young men and women who have volunteered to put their lives on the line to defend us, and who have lost a limb in the process.

It's not quite clear the nation owes the same consideration to J. Random Citizen who gets himself racked up on the highway, say, by drinking and driving, or even through plain bad luck.

Re:

[Firehed]

Hmm... my dad is always complaining about not having three arms. It would be nice... but I fear what the hand of a middle arm would look like. Would any hand gesture be giving someone the finger?