Three years ago, Lee Spievack sliced off the tip of his finger in the propeller of a hobby shop airplane.
What happened next, Andrews reports, propelled him into the future of medicine. Spievack's brother, Alan, a medical research scientist, sent him a special powder and told him to sprinkle it on the wound.
"I powdered it on until it was covered," Spievack recalled.
To his astonishment, every bit of his fingertip grew back.
"Your finger grew back," Andrews asked Spievack, "flesh, blood, vessels and nail?"
"Four weeks," he answered.
That powder is a substance made from pig bladders called extracellular matrix. It is a mix of protein and connective tissue surgeons often use to repair tendons and it holds some of the secrets behind the emerging new science of regenerative medicine.
"It tells the body, start that process of tissue regrowth," said Badylak.
Badlayk is one of the many scientists who now believe every tissue in the body has cells which are capable of regeneration. All scientists have to do is find enough of those cells and "direct" them to grow.
"Somehow the matrix summons the cells and tell them what to do," Badylak explained. "It helps instruct them in terms of where they need to go, how they need to differentiate - should I become a blood vessel, a nerve, a muscle cell or whatever."
If this helped Spievack's finger regrow, Badylak says, at least in theory, you should be able to grow a whole limb.