by William Wells

The ancient Egyptians knew it. They said as much on a papyrus dated to around 2500 B.C. — that spinal cord injury (SCI) was "an ailment not to be treated." Santiago Ramón y Cajal, the father of neuroscience, even knew why it must be so. Yet here was Christopher Reeve, the former Superman, saying that it wasn’t true — that SCI didn’t have to be incurable.

A cut-away view of the spinal cord.

By the time that Reeve was paralyzed in a riding accident on May 27, 1995, little progress had been made in reversing Ramón y Cajal’s original observation. One hundred years earlier he found that nerves of the central nervous system (CNS — the brain and spinal cord) were incapable of regenerating, unlike the nerves of the peripheral nervous system (PNS — all the other nerves that travel all over the body). That doctrine had survived largely intact into the 1990s, making Reeve’s talk of a cure sound naïve.

But now, just a few years later, Reeve’s optimism is ascendant. "The regeneration field is exploding right now," says Ben Barres of Stanford University, California. A new generation of neuroscientists, trained in the young field of nerve growth and guidance, is hungry to apply their knowledge to CNS regeneration. They are starting to understand why the CNS is so hostile to nerve growth. And they are using newly discovered stem cells to generate the different types of nerve cells needed to repopulate and rebuild a devastated spinal cord.