Rebuilding tissues

Behold, a "ghost heart!" All of the living cells have been washed off this pig heart, so it can provide a scaffolding for human stem cells to grow a new, working heart. So far, scientists at the Texas Heart Institute have successfully implanted tissue-engineered hearts like this one into rats and pigs, and they hope to someday do the same in humans. Read about this and other bio-engineering experiments in the new TED Book, “Super Cells.” Photo courtesy of RMR Labs, Texas Heart Institute.