The problem: More than 3,200 people are on the waiting list for a heart transplant in the United States. Some won't survive the wait. Last year, 340 died before a new heart was found.
The solution: Take a pig heart, soak it in an ingredient commonly found in shampoo and wash away the cells until you're left with a protein scaffold that is to a heart what two-by-four framing is to a house.
Then inject that ghost heart, as it's called, with hundreds of millions of blood or bone-marrow stem cells from a person who needs a heart transplant, place it in a bioreactor -- a box with artificial lungs and tubes that pump oxygen and blood into it -- and wait as the ghost heart begins to mature into a new, beating human heart.