Lab Frogs Regrow Limbs, Opening Door for Regeneration Studies

Some animals regrow missing body parts with ease. But humans, and African clawed frogs, are not creatures with those natural capabilities. This is why a recent scientific breakthrough is so exciting for the science and medical community. In a lab, scientists were able to regrow the frogs’ limbs using a new experimental technique. The regeneration technique involves a unique five-drug cocktail. Although the new frog legs are not aesthetically perfect, they are incredibly functional.

African Clawed Frog regrows legs:limbs in new regeneration study
Smithsonian Institution

As described in The New York Times, scientists left the drug cocktail on the frogs for 24 hours. They used a silicon cap called a BioDome to administer the drugs. And then, over the course of 18 months, the frogs regrew a leg-like structure. This structure was functional and included nerves, muscles, bones, and toe-like projections. An amazing achievement.

The scientists, a team from Tufts and Harvard University’s Wyss Institute, published their full regeneration findings in the journal Science AdvancesNirosha Murugan, the first author of the paper, had this to say about their results:

It’s exciting to see that the drugs we selected were helping to create an almost complete limb. The fact that it required only a brief exposure to the drugs to set in motion a months-long regeneration process suggests that frogs and perhaps other animals may have dormant regenerative capabilities that can be triggered into action.

And that truly is astounding. It’s a fascinating hypothesis scientists will surely explore more going forward. According to a release, “Humans are capable of closing wounds with new tissue growth, and our livers have a remarkable, almost flatworm-like capability of regenerating to full size after a 50% loss.” However, we are not very good at restoring large or structurally complex limbs. In fact, the release shares, “we tend to cover major injuries with an amorphous mass of scar tissue, protecting it from further blood loss and infection and preventing further growth.”

However, the BioDome used in the study could make all the difference.

BioDome used to regrow frogs legs/limbs in regeneration study
Tufts

David Kaplan, co-author of the study, shares:

Using the BioDome cap in the first 24 hours helps mimic an amniotic-like environment which, along with the right drugs, allows the rebuilding process to proceed without the interference of scar tissue.

So what does this mean going forward? “We’ll be testing how this treatment could apply to mammals next,” says corresponding author Michael Levin. “Covering the open wound with a liquid environment under the BioDome, with the right drug cocktail, could provide the necessary first signals to set the regenerative process in motion. It’s a strategy focused on triggering dormant, inherent anatomical patterning programs, not micromanaging complex growth, since adult animals still have the information needed to make their body structures.”

Basically, our bodies may know how to replicate themselves, they just need a little help. From frogs regrowing limbs to the future of regeneration, this scientific breakthrough could have major impact.