Drug device spurs lost limbs to regrow… in frogs, at least.

Science News covers a device that coaxes amphibians’ cells to remember how to regrow amputated arms and legs:

“The cells of the frog already know how to make frog legs,” having done so when the animal was a developing embryo, says Michael Levin, a developmental biologist at Tufts University in Medford, Mass. “Our goal is to figure out how to convince them to do it again.”

Levin’s team amputated the right back legs of 115 adult African clawed frogs (Xenopus laevis) at the knee. Roughly one-third of those frogs received “BioDomes,” silicone sleeves that cover the wound. To another third of the frogs, researchers attached BioDomes holding a silk-based gel that contained five chemicals, including a growth hormone, a nerve growth promoter and an anti-inflammatory substance. The BioDomes stayed on for 24 hours and then were removed from the frogs’ legs. The remaining third didn’t receive any treatments before being placed back in their tanks.

After 18 months, the frogs that received the chemicals had regrown the limbs and had nubs where toes would typically grow. The amputees kicked, stood and pushed off the walls of their tanks using their regrown legs, Levin says.

The team has moved on to similar work in mice, using the same cocktail and new ones. Levin’s research also points to electricity’s role in shaping the growth of body parts, so the researchers are adding compounds to the cocktail that alter the electrical state of cells.

Someday, scientists want to be able to regrow human limbs and organs.

You can read more of Levin’s team’s “multidrug delivery” research here, at Science Advances.