Stem cell may repair hearts

Stem cells appear to repair damaged organs

By Richard Black BBC science correspondent

New research announced at the world's biggest meeting of heart doctors suggests it will soon be possible to use the body's own stem cells to repair the damage caused by heart attacks.

Doctors speaking at the annual meeting of the American Heart Association in Chicago, US, said they had used stem cells from bone marrow in a number of patients, with encouraging results.

Meanwhile other researchers have discovered how to use human skin to grow new blood vessels.

They hope these engineered vessels can eventually be used in standard heart bypass operations.

Heart repairs

For a few years now scientists working with animals have seen that stem cells from bone marrow can help repair a damaged heart.

These cells are usually destined to become various types of blood cell - but in the heart, they are transformed into muscle, replacing tissue which has died as a result of a heart attack.

Now researchers in the UK have tried it in human patients. They extracted bone marrow from 14 people who had just had a heart attack, and injected cultured cells from the marrow back into the patients' hearts.

Within weeks of treatment, the heart wall was able to contract better, improving the flow of blood around the body.

The doctors now plan to extend their trials to a larger group of people.

Growing vessels

Another team of researchers, from the United States, announced they had managed to turn skin into blood vessels.

They started with a patch of skin less than a square centimetre in size, and wrapped it around a thin cylinder.

Then they saturated it with chemicals which the body normally uses to produce new arteries, and saw the skin grow into a tiny tube which seems to behave like a normal blood vessel.

The tubes have performed well in animal tests, and the researchers hope to begin human trials within a year, using them as a limitless supply of grafts for bypass operations.