Scientists repair injured rat spinal cords

A team of researchers at Washington University School of Medicine, St Louis, has grown nerve cells in the laboratory and used them to repair damaged adult rat spinal cords. The scientists used embryo stem cells - cells that can grow into any type of body tissue - to obtain a supply of oligodendrocytes, a special type of nerve cell. When transplanted, the oligodendrocytes repaired damaged nerve fibres by re-insulating them with myelin, the fatty sheath that surrounds healthy nerve cells.

Dr John McDonald, head of the team, said his research is relevant 'because conditions that result in myelin loss, such as spinal cord injury, stroke, multiple sclerosis and transverse myelinitis, occur mainly in adults'. The results of the study were published in the May 23 issue of Proceedings of the National Academy of Sciences.

John Cavanagh, of the International Spinal Research Trust, told the Lancet that he welcomes the study. He points out that nerve fibres are often left intact, but functionless, after a spinal injury because they have lost myelin following the body's response to the trauma. But he also warned that complete fibres would need to be myelinated to allow transmission of nerve impulses.

Dr McDonald admits there are still hurdles to overcome, but hopes that cell transplantation techniques will be used to treat spinal injuries within the next five to ten years.