Paralyzed dogs in a U.K. study have been restored to mobility thanks to injected cells, letting Cambridge University scientists dare to hope that the technique could eventually aid the treatment of humans.

In experiments done by the U.K. Medical Research Council's Regenerative Medicine Centre and Cambridge University's Veterinary School, 23 hobbled dogs who had suffered spinal injuries were injected with cells grown from the nasal passages of healthy dogs. The cells were injected into their spines.

A neutral control substance was injected into 11 other injured dogs. No improvement occurred in the control group, but many of the 23 cell transplant dogs were able to walk again on a treadmill with the help of a harness.

"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," the BBC quoted Prof. Robin Franklin, a regeneration biologist at the Wellcome Trust-MRC Stem Cell Institute and report co-author, as saying.

"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."

The results were published in the November issue of the neurology journal Brain.

According to the BBC, researchers say the transplanted cells regenerated nerve fibres across the damaged region of the spinal cord, allowing the dogs to regain use of their back legs and co-ordinate front-leg movement.

However, the restored nerve fibres only stretched over short distances, which calls into question the applicability in humans.

"This is not a cure for spinal cord injury in humans — that could still be a long way off," Prof. Geoffrey Raisman, chair of Neural Regeneration at University College London, told the BBC. "But this is the most encouraging advance for some years and is a significant step on the road towards it."