One cell is all it takes to rebuild a complete, functioning flatworm, researchers have learned. The animals possess a special type of cell throughout their bodies, which shares some qualities with human embryonic stem cells. If scientists can find out how this special cell works, they could someday study ways to use the cells for human tissue regeneration.
The findings are the first time pluripotent stem cells have been found in an adult animal, according to researchers at MIT and the Howard Hughes Medical Institute.
Pluripotent stem cells have a unique ability to turn into any kind of cell, which is what makes them so valuable for disease research, tissue regeneration and other fields. But these cells are only found in embryos, or are induced in complex lab processes. Adults have stem cells, but they have greater specificity — blood stem cells can turn into any constituent part of the blood, and skin stem cells can turn into skin or hair, but they can't turn into other cells like neurons, for instance.
But flatworms, or more properly planarians, seemingly can create all their cells from a limited clump. If you cut off a chunk of it, it won't die — you'll soon wind up with two fully fledged, healthy planarians. Researchers wanted to know whether the animals' regenerative properties were the work of one "all-purpose" stem cell, or groups of specific stem cells working together.
To figure this out, researchers led by Peter Reddien, Daniel Wagner and Irving Wang at MIT exposed the worms to ionizing radiation, robbing their cells of their ability to divide and regenerate. Without the ability to grow new cells, the animal would slowly die. The team killed off all the dividing cells except a rare group called cNeoblasts, and watched as those remaining cells divided to form large colonies of replacement cells.
Then they did something truly weird. Wang and Reddien harvested a single cNeoblast from one type of planarian. Then they gave a different kind of planarian, one that did not have its own neoblasts and couldn't regenerate, a lethal dose of radiation. Its tissues started to die, from the head down toward its tail. Then they implanted the first worm's neoblast into the tail of the second, dying worm.
They watched as the transplanted cNeoblast multiplied, differentiated and "ultimately replaced all the host's tissues," according to a news release from the Whitehead Institute for Biomedical Research. Descendants of the single neoblast cell differentiated into neuronal, intestinal and other adult cell types, taking over the jobs of the host's dying cells. The newly restored worm was an exact genetic copy of the cNeoblast donor. All this from one single cell.
The results were published in today's issue of the journal Science.
In a news release, Wagner said planarians have already solved the problem of regeneration, and scientists want to determine how it works.
"One day, we'll examine what are the key differences between what's possible in this animal and what's possible in a mouse or a person," he said.
great piece, however i still wonder what stops regeneration from becoming a tumor or cancer?...
we've already found out that with a matrix of collagen the stem cells will recognize and fill the matrix. they made a pig's heart this way if i remember right. it's the same thing except they found that it only takes one stem cell.
OMG ZOMBIE WORMS GONNA TAKE OVER THE WORLD!!!!
So if we successfully figure out how to do this for 1 human and cut off his 10 fingers. Then got a single donor to have his cells implanted to each of the 10 fingers which would then produce 10 exact genetic copies of the donor...
Did the human soul get divided for each for each of the 10 additional copies?
Also, whose soul is in the 10 copies? The donor or the owner of the 10 fingers?
@chrisbasilio...your comments are just plain rubbish, please don't start a religious debate on this site
Our conscienceness is our brain, but people believe they have a soul because of the brain's inability to perceive itself. So if we did make copies of a person that way, they would just be artificial conceived twins. Each one would have his/her own fully functional mind and personality. There is no supernatural element in this.
The day asking questions is rubbish for everyone will be the day that Science dies.
what would happen if neoblasts from two different worms were placed at opposite ends of the worm instead of one neoblast from one worm?
@chrisbasilio...then ask a scientific question or at least one that makes sense
@drchuck1... precisely my point. who are you to say what is scientific or not, what makes sense or not? If you had been around when people didn't know the world was round yet, you would probably have thought the notion of the world being round is rubbish also.
ok, last try, don't start religious debates on here (you refering to a soul) this is not the place for it, your obvious trolling is not welcome
Since a single cell is capable of storing the information for a complex organism, it makes sense that a single cell, or small group of cells would be capable of forming a subset of organisms, depending upon external conditions.
Under this premise, I recently wrote a novel. It is about an alien species that is essentially a pool of totipotent cells, capable of forming itself into diverse morphology.
I believe that the most highly evolved organism is that which is in control of its evolution. We are pursuing this path as we alter our own genetics. If we survive long enough for space travel, we will have to adapt to a broad range of conditions depending on length of travel and conditions of the destination planet(s). It is more economical to adapt the organism to the external conditions instead of adapting the external conditions to the organism.
Last try also. Nobody dared to publicly ask if the world is round when everyone thought it was flat, this perception didn't change until Columbus didn't fall over the edge. Is it wrong to ask about the soul when a discovery like this can prove/disprove its existence without "falling over the edge"?
You fear/worry about a religious debate when we might be on the cusp of proving/disproving something important with this latest discovery.
Go create your own popsci website and write all the policies you want on what to ask and what not to ask.
Chrisbasilio has a point. to adapt in an everchanging world, we have to ask the question regardless how unacceptable it can be. Science asks the questions to ponder on what the answers may be like and religious beliefs about souls could not be dismissed. However, Science deals with facts and not belief which makes the religion subject not relative to worm regeneration. Personally, I like the idea having two souls, but in this way, it is not separated. Remember that the single cells regenerated after the separation thus creating a new singular form of each, as logic dictates, it would be the same with souls (if it does exist). The best example is twins that started off in a single cell, separated, and then 2 kids... However, there was psychological study that twins have a "certain personality connection" thus can be relative to souls. This is another issue though.
Always remember that everything in this world is inter-connected and are part of larger family, it is the individuality that makes it unique, even cell-wise.
this is not an appropriate forum for discussing beliefs, having a soul is a belief, not science, just as you stated... there are appropriate forums to discuss such things, he does not need to be silent or not ask such questions, just go where this is freely debated on a site intended for such subjects
No one seems to have a problem with his comment other than you. Quit trying to pick a fight over someone's beliefs and focus on the article. The issue would have vanished by now if you would have just ignored it and moved on.
I have read several of your posts here and usually enjoy your opinions and observations. On this I must defer.
Chrisbasilio’s question didn’t seem religious but philosophical. It seems that your objection is to the belief in a living soul (a predominant theme in many religions and cultures). To that point, if something is unobservable doesn't prove its non-existence it only proves that it hasn't been observed. Take the subject of this article for instance. This type of regeneration had been thought impossible by some, theorized by others, and now we have an observed occurrence. It is the discussion of thoughts and ideas that lead to the exploration of what can observe that gives us such revelations.
Please don't take science back to the dark ages by attempting to suppress thoughts and opinions that you dislike or disagree with. The free expression of thought and ideas will lead us to the observation of the facts (or truth if you prefer.) Many thanks to you for your patient understanding and to PopSci for this article.
@merlinus, @Darrell, @toferus2001, @quantumwarrior
Thanks for the support and/or comments.
This article made me ask another question. The irony of it all is that I would not have thought of this had drchuck1 not keep bringing up religion.
But Eve was created from Adam's rib. Doesn't this scientific discovery describe Eve's creation?
There is no religious side taken with this discovery. If you are religious, it proves that the bible as early as genesis is true. If you are not religious, it brings the idea of creating life without going through infancy closer.
If this comment just causes more trouble that it is worth to the website owners just delete this.
@chrisbasilio: I have my own questions, if God created Adam from dust, why did he/she need Adams rib for Eve? If you are stating that Eve's creation is similar to this experiment, you would have to take into account that Eve would simply be a clone of Adam, therefore she would have been he. You can not clone a human being using the study above to create something completely different (Different as in DNA make up). It just would not make any sense.
As in the second comment: If you are not religious, it brings the idea of creating life without going through infancy closer. Non-Religious people, I would assume, believe in evolution. I dont think they believe they just appeared unless there was some form on intervention from aliens.
Overall, I think the article was a good one. It shows that within time, we can as one mentioned control our destiny. We read about studies of parents modifying DNA for their unborn, soon, they will have the option of cell-regeneration, bring us closer to avoiding death and becoming the next version of human beings.
Do unicorns use this way of regeneration to reproduce themselves? Several scholars are wondering about this, because they don't believe in unicorns coming from a parallel dimension.
If you believe in souls (and there's no hard evidence about this) then you must acept another kind of beliefs about this discovery, right?
But, alas, this is a SCIENCE news site and, if you want to talk about beliefs, you should go to a religious forum.
Please, read chrisbasilio's last message. He's obviously not on the science side of the spectrum.
@merlinus...it appears i may have made an error in judgement, of course i don't wish to take science back to the dark ages, loved the article, my appologies to anyone i may have offended
Regarding can not clone a human being using the study above to create something completely different - I think you are right on this.
Regarding they just appeared unless there was some form on intervention from aliens - I have always thought our natural technological progression as a species would be to master creating mechanical beings (robots) first then bio-mechanical then create purely biological-based beings. But this article points to a start on the creation of biological beings even before mastery of the bio-mechanical.
Think about what was just accomplished here. From an extremity (tails/fingers/neoblast/cell/dust), a separate, new and mature being emerged - some would argue we merely created a new consciousness but to me we've just created a new life. It does have a body to go around with that new consciousness and could act and proceed on its own accord.
I don't know. I just feel like we as a species just crossed a significant threshold with what was described in this article.
Amazing, just shows what nature can do...