Another Stem Cell Advance

Stem cells have been used to regenerate damaged spinal cords in rats

For the first time, scientists have successfully regrown part of the spinal cord responsible for voluntary movement in mice, using patches of stem cells. While we're still a long way from a cure for paralysis and other spinal cord injuries in humans, the success of the experiment goes against what researchers had assumed for many years - that you can't regenerate neurons in the spinal cord.

The set of cells in question are the corticospinal axons, thought to be the most important motor system in humans. "It has not been successfully generated before," said one of the team, Mark Tuszynski from the University of California, San Diego. "Many have tried, many have failed - including us, in previous efforts."

By grafting stem cells into the injured rats and specifically directing them to develop as spinal cord cells, forelimb movement was improved in the animals - the partially paralysed rats were once again able to reach out and grab treats. The results go against an existing belief that corticospinal neurons lack the internal mechanisms to be able to regenerate in this way.