They noted that nerve fibers do have the ability to regrow after a spinal injury, but they're blocked by scar tissue that develops around the injury.

After the gel is injected as a liquid into the spinal cord, it self-assembles into a scaffold that supports new nerve fibers as they grow up and down the spinal cord and penetrate the site of the injury.

Six weeks after the gel was injected into mice with a spinal cord injury, the mice showed great improvement in the ability to use their hind legs and walk. The research was published in the April 2 issue of The Journal of Neuroscience.

"We are very excited about this. We can inject this without damaging the tissue. It has great potential for treating human beings," lead author Dr. John Kessler, a professor of stem cell biology at Northwestern's Feinberg School of Medicine, said in a prepared statement.

However, he added that it's "important to understand that something that works in mice will not necessarily work in human beings. At this point in time, we have no information about whether this will work in human beings."

"There is no magic bullet or one single thing that solves spinal cord injury, but this gives us a brand new technology to be able to think about treating this disorder. It could be used in combination with other technologies including stem cells, drugs or other kinds of interventions," Kessler said.

He and his colleagues are working on developing the nano-engineered gel to be approved as a pharmaceutical by the U.S. Food and Drug Administration. If they make good progress, a human clinical trial of the gel could begin in several years.

—Robert Preidt

SOURCE: Northwestern University, news release, April 2, 2008