Amputees will be glad to learn that we might not have to be jealous of a lizard’s ability to regrow its tail much longer. According to recently published research from NYU's Langone Medical Center, the stem cells found in fingernails might be the secret to developing treatments that could one day allow for complete limb regeneration in humans.
As we all know, the nails on our fingers and toes grow back. Through experiments on mice, the research team at NYU has discovered the chemical process by which this occurs, the process by which stem cells in the nails trigger their own regeneration. That all seems logical, but the surprise was when the scientists realized that these stem cells also promote bone regeneration in addition to that of the nail—meaning that these stem cells could, in theory, allow a human to grow back an entire finger, toe, or limb.
It might seem like far-off science fiction, but cases of finger regeneration are already a reality. For example, a woman named Deepa Kulkarni underwent a tissue regeneration procedure that resulted in a new pinky in just seven weeks. In this particular case, the patient used a powder called MatriStem that induced stem cells to regrow the tip of her finger. Scientists concluded at the time, however, that this was only possible because she lost only the tip of the finger and because there was still a “bit of nail” and its tissues present.
But what if we could take these nail stem cells and inject them where they are not? Say, in the upper arm? Thus far, clinical trials have been successful in mice.
“When they forced the production of [these stem cells] in mice, the team managed to regrow bone and tissue without any of the natural stem cells being present at all,” Popular Science reported. “This has huge implications for the treatment of amputations—the experiment was only performed on mice, but if the technique holds true for humans, this could be the beginning of the end for lost limbs.”