Published on 19 Nov 2012 Sections ,

Paralysed dog breakthrough offers hope for humans

Scientists have restored movement in the legs of paralysed pet dogs in a discovery that creates new hope for paralysed human patients.

A study of pet dogs, by scientists at Cambridge University, has shown cells taken from the dogs noses can improve nerve connections in their spines.

The cells, olfactory ensheathing cells (OECs), support nerve fibre growth that connects the nose to the brain. However, doctors found the cells can also regenerate nerve fibres in damaged spinal cords.

One previously paralysed dachshund, Jasper, was described by its owner “whizzing around the house” after undergoing the treatment.

May Hay, from Cambridge, said: “Before the trial, Jasper was unable to walk at all. When we took him out we used a sling for his back legs so that he could exercise the front ones. It was heartbreaking.

We’re confident that the technique might be able to restore at least a small amount of movement in human patients – Professor Robin Franklin

“But now we can’t stop him whizzing round the house and he can even keep up with the two other dogs we own. It’s utterly magic.”

“Extremely exciting”

Professor Robin Franklin, one of the study leaders from Cambridge University, said: “Our findings are extremely exciting because they show for the first time that transplanting these types of cell into a severely damaged spinal cord can bring about significant improvement.”

In a study on 34 pet dogs, which had all suffered spinal injuries due to back problems or accidents, a group of dogs were injected in the damaged area of their spines with the cells from their own noses. Another group was injected with a placebo treatment.

Dogs were tested for neurological function at one month intervals and had their walking ability assessed on a treadmill.

Significant improvement was seen in the dogs injected with OECs, but not those receiving the placebo treatment, according to the findings reported in the journal Brain.

Researchers said, however, that the new nerve connections in the spinal cords were only generated over short distances between damaged nerves.

Limited benefits

Professor Franklin warned patients and their loved ones not to expect too much from the discovery.

“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 that’s a long way from saying they might be able to regain all lost function,” he said. “It’s more likely that this procedure might one day be used as part of a combination of treatments, alongside drug and physical therapies, for example.”

Professor Geoffrey Raisman, chair of neural regeneration at University College London, said: “This is not a cure for spinal cord injury in humans – that could still be a long way off. But this is the most encouraging advance for some years and is a significant step on the road towards it.

“This shows convincingly that the beneficial effects previously reported in rodents can be produced in other species.

“That is encouraging for application in human injuries. But from a clinical perspective, the benefits are still limited at this stage. This procedure has enabled an injured dog to step with its hind legs, but the much harder range of higher functions lost in spinal cord injury – hand function, bladder function, temperature regulation, for example – are yet more complicated and still a long way away.”

Doctor Rob Huckle, head of regenerative medicine at the Medical Research Council, which funded the study, said: “This proof of concept study on pet dogs with the type of injury sustained by human spinal patients is tremendously important and an excellent basis for further research in an area where options for treatment are extremely limited.”