Paralysed dogs walk after nose job - but can it help humans?
Hope for paraplegic humans after scientists make paralysed dogs walk by injecting nose cells into spine
AN EXPERIMENT that restored movement to paralysed dogs by injecting their nose cells into their spinal cords has given hope to humans with spinal cord injuries.
In research funded by the Wellcome Trust and published in the journal Brain, scientists used 34 dogs left paralysed or without feeling in common situations such as road accidents.
Olfactory cells were taken from the dogs and cultured in the laboratory before being injected into the spinal cord.
Unlike other parts of the adult mammalian body, the olfactory system is able to continuously regenerate. Scientists have long thought that olfactory ensheathing cells, which guide this regeneration, could be used in therapies that promote spinal cord repair.
Robin Franklin of the Wellcome Trust-MRC Cambridge Stem Cell Institute told The Times: "The principle is, we take these cells from one location where they get nerve fibres to grow, and take them to a location where nerve fibres don't usually grow."
Six months after the treatment, many of the dogs were able to walk with the aid of a harness.
"It's pretty significant," said Professor Franklin. "The gait is still not perfectly normal and they still have difficulty defecating and urinating. But for the dogs it's pretty good news."
The effect of the olfactory cells has been to guide the growth of a "bridge" between damaged and undamaged parts of the spine. However, regeneration did not take place over the long distances required to repair the connection between the brain and spinal cord.
This caveat is significant because it means that the curative effects of the treatment would be less pronounced in humans.
Franklin said: "The issue is whether the recovery in animals with four legs would look quite so good in an animal with two legs, where communication with the brain is more important."
However, the success of the experiment does give some hope to paraplegic humans.
"We're confident that the technique might be able to restore at least a small amount of movement in human patients with spinal cord injuries... but it's not the magic bullet that's going to solve spinal cord injury," says Franklin.