STEM cells could be used to cure spinal injuries like those suffered by the Superman actor Christopher Reeve after scientists revealed yesterday that the technique had worked in rats.
Californian researchers announced in Edinburgh the first successful transplant of human embryonic stem cells to an animal to treat spinal injuries.
The stem cells were adapted to become nerve-like cells and injected into rats which had had some of the nerves in their spinal cord severed. The treatment repaired nerve damage which had prevented the rats from being able to support their tails or one of their hind legs.
In previous experiments, such cells were rejected by the immune system.
Professor Tom Okarma, the chief executive of the Geron Corporation, who announced the breakthrough, said: "This is a pretty dramatic example of proof of concept."
Prof Okarma was speaking at the launch of the Scottish Stem Cell Network, at the Royal Society of Edinburgh, which will bring together the country's world-leading scientists in the research area.
Dr Marilyn Moore, the network's co-ordinator, said: "This is an extremely encouraging step towards trials in humans."
However, she said scientists were cautious about starting such tests yet because of opposition in the United States and Europe. Possible new European laws could restrict trials in Britain, where they are currently permitted.
The research was partially funded by the Christopher Reeve Paralysis Foundation, which was established by the actor after he was paralysed in a riding accident in 1995.
The new network is backed by ?190,000 funding from Scottish Enterprise. Scotland holds 9 per cent of the world's patents from stem cell research, which is being spearheaded by the Institute for Stem Cell Research at Edinburgh University and the Roslin Institute in Midlothian.
Stem cells can be differentiated into any type of cell and hold the potential for repairing a range of damaged organs.