Published by
Stanford Medicine

Stanford News, Stem Cells

Limb regeneration mysteries revealed in Stanford study

Although you may not know it, mammals (even humans!) can regrow small portions of amputated digits like fingers and toes. This remarkable ability has perplexed scientists for some time, as they pondered whether it was due to the presence of already-existing adult stem cells in each of the various tissues that make up the end of a finger (blood vessels, bone, skin and tendons, for example), or if specialized cells near the site of injury were somehow able to regress developmentally and gain the capacity to become many different tissue types. As described in our release today:

[The researchers…] have shown that damage to a digit tip is repaired by specialized adult stem cells that spend their lives quietly nestled in each tissue type. Like master craftsmen, these cells spring into action at the first sign of damage, working independently yet side-by-side to regenerate bone, skin, tendon, vessels and nerves. But just as you wouldn’t ask a mason to wire your house, or an electrician to put on a new roof, the division of labor among these stem cells is strict. Each is responsible solely for its own tissue type.

In contrast, the blastema theory invokes a new pluripotent cell type formed out of urgency from previously specialized cells. This jack-of-all-trades cell discards its former profession and instead jumps in to indiscriminately regenerate all the tissue types of the limb.

The work was performed by postdoctoral scholar Yuval Rinkevich, PhD, in the laboratory of Irving Weissman, MD. Weissman had this to say about the findings:

We’ve shown conclusively that what was thought to be a blastema is instead simply resident stem cells that are already committed to become specific tissue types. The controversy about limb regeneration in mammals should be over.

According to Weissman, the study is particularly important because, in the past, some scientists and national media reports have championed the idea that money allotted by the California Institute for Regenerative Medicine for stem cell studies would have been better funneled to blastema research.

Photo by Yuval Rinkevich

5 Responses to “ Limb regeneration mysteries revealed in Stanford study ”

  1. Dr Rose Fuhrmann Says:

    what’s new?
    This was observed, clinically explored and successfully applied by surgeon Cynthia Illingworth at the Sheffield Childrens’ Hospital UK in the early 1970s. Obsevation of limb regeneration in animals go as far back as 1934.
    Major research on the underlying physiological processes and possible clinical applications of ELF direct cureents was done by Robert O.Becker (1923-2008 – orthodedic surgeon and reseracher at Upstate Medical Center in State University of New York, Syracuse)and his team. For further detail see: RO Becker, G Seldon, The Body Electric, first published 1985: and RoBecker (1990, Cross currents,The perils of electropollution – the promise of electromedicine, published by Penguin Group NY.
    Both a very interesting read – not just for the scientist!

  2. Nihit Mehta Says:

    How is this helpful? Can this research ever be duplicated in humans in large scale, can you regrow a leg or hand? Perhaps a brain? Digit tips, yeah!!! An advance of science.

  3. Mentihiaht Says:

    Tips don’t contain important bones, and many times they can regenerate without much effort. Hence, I guess, what I am asking is what’s the originality? A student of science, knows new skin/tissue (primary constituents of digit tips)are regrown from stem cells. It really doesn’t take much effort to say, that the stem cell that does this regeneration is specialized. I fail to see the controversy, along with the tittle for this issue. How does regeneration of finger tips, constitute a regeneration of digit tips.

  4. lisa Says:

    my baby girl lost her thumb when she was 2 years old and is now 4 years old . i do hope regeneration will go on to new way of regrow .

  5. Manas Guttal Says:

    Will some day could there be regeneration of human leg? I lost my legt leg below knee in an Accident.


Please read our comments policy before posting

Stanford Medicine Resources: