Stem cells used to grow red blood cells in Scotland
Cannot play media. Sorry, this media is not available in your territory.
Just over one million litres of blood was collected from donors in the UK in 2010.
This enormous and expensive effort is currently the only way possible to produce the vast amount of blood needed for the millions of blood transfusions carried out each year.
A team of scientists in Edinburgh, Scotland is growing red blood cells in a laboratory, using embryonic stem cells, but it has a long way to go before it can achieve this on a large scale.
The Health Show is broadcast on BBC World News on Saturdays at 1010 and 2010 GMT and on Sundays at 0710 and 2310 GMT. The programme is supported by the Gates Foundation.