Lab-grown heart muscles transplanted into a human for the first time

Researchers in Japan have successfully carried out the world's first transplant of lab-grown heart muscle cells, in a move which could significantly reduce the need for heart transplants. To grow the heart muscle cells, the scientists from Osaka University first took adult stem cells and reprogrammed back into their embryonic-like state. From this point, the researchers were able to coax the cells into becoming whatever form they wanted -- in this case, heart muscle cells.

These cells were then placed on small, degradable sheets, which were used to cover the damaged areas of the patient's heart. The patient who received the transplant suffers from ischemic cardiomyopathy, where the heart has difficulty pumping because its muscles don't receive enough blood. In some cases, this condition requires a heart transplant, but the researchers hope the new muscle cells will secret a protein that will help regenerate blood vessels, thereby improving the heart's overall function.

The patient -- the first of 10 across this three-year trial -- is now recovering in hospital and will be monitored for the next year. If successful in the long term, the procedure could become a viable alternative to heart transplants, since creating these cells is much easier than finding suitable donor hearts, and they are considerably less likely to be rejected by the recipient's immune system.