Professor Geoffrey Raisman, chairman of a committee on neurological regeneration at the Institute of Neurology and director of the Spinal Repair Unit, both at University College London, has announced the first British attempt to treat paralysed spinal cord injury patients with their own stem cells. His method involves taking cells from the lining of the nose and transplanting them into the spinal cord or damaged nerve, where the cells are able to form a bridge connecting the severed ends. A pilot study will take place at the National Hospital for Neurology and Neurosurgery in Queen Square, London early next year. The first patients will be those suffering an injury typical of motorbike accidents, where nerves in the arm have been pulled out of the spinal cord, leading to complete paralysis and loss of sensation.
Speaking at a meeting held at the Royal College of Physicians, Professor Raisman explained the rationale behind the new treatment: 'When a nerve fibre is severed it attempts to regrow, it's failure to do this is due to the disruption of the pathway along which the nerve fibres need to travel. It is as if part of a roadway has been washed away. The cars are still able to travel, the drivers remember where they wish to go, the tanks are full of fuel. What is required is to repair the roadway, providing a bridge over which the severed nerve fibres can grow back'. Although damaged nerve cells will often regrow, they struggle to sprout in the right direction. Professor Raisman's technique aims to place a thin layer of stem cells from the patient's nasal cavity between the severed nerves and the spinal cord to help them to regrow and reconnect.
The stem cells to be used in the treatment, 'olfactory ensheathing cells', were discovered by Professor Raisman in 1985. They are the only nerve cells that continue to grow in adulthood, and as they are derived from the patient there is no danger of rejection or need for expensive and potentially damaging immune suppressing treatments. Although there have been previous attempts to treat nerve damage, Professor Raisman's research is remarkable as it rests on a 40-year programme of experiments with animals. In laboratory rats with severed spinal cords, the treatment has restored their ability to reach and climb. If the technique is successful in humans it could open the door for treatments for more severe spinal cord injury, as well as stroke, blindness, and deafness caused by nerve injuries.
Professor Raisman's work was recognised last week when he was presented with a research medal in the name of Christopher Reeve, the late Superman actor who campaigned for stem cell research after being paralysed in a riding accident in 1995. Professor Raisman has previously worked at Harvard, but did the majority of his work on the neural stem cells at the National Institute for Medical Research in Mill Hill, London. Speaking about the background to the clinical trial next year Professor Raisman said, 'I have been patient. I didn't jump in the dark. I have grown through the research all these years. It was in 1985 I discovered the cells. It has taken twenty years before I felt we had the technology to apply this to people'.