Scottish researchers have taken a major step towards the 'holy grail' of haematology - the ability to produce a limitless supply of artificial blood cells. The team successfully produced significant amounts of red blood cells from stem cells harvested from spare IVF embryos.

Professor Marc Turner, Clinical Director of the Scottish National Blood Transfusion Service (SNBTS), told the Telegraph that 'Synthetic blood could transform medicine if made on an industrial scale'. Traditional blood donation is currently the mainstay of medicine, but there is a constant threat of shortages and the risk of infections being passed between donor and recipient. Synthetic blood is guaranteed free of disease.

The SNBTS team hope clinical trials of the synthetic blood will begin within five years. Dr Jo Mountford, from the SNBTS, told the Independent 'We're confident that we'll get the numbers of mature red blood cells that we need for clinical trials'.

But the new blood will have to meet strict regulations before it is available for use and some experts have expressed concern.

'Many good people who donate cord blood, adult blood or bone marrow, would not wish to be in anyway associated with this proposed destructive use of embryos, let alone research involving tissue from aborted babies',  Josephine Quintavalle, director of the Campaign for Reproductive Ethics, reportedly said last year.

SNBTS were given a £3 million Wellcome Trust grant to develop universal donor group (O negative) blood using stem cell technology.