PROMOTING GROWTH OF AXONS BEYOND THE AREA OF INJURY
Martin Oudega, PhD • Daniel J. Liebl, PhD

Functional recovery after SCI most likely will require the successful regeneration and re-entry of severed axons into the spinal cord to establish re-connection with their targets. Understanding how regeneration occurs may depend on how the injury environment affects regeneration as well as knowing what happens both anatomically and genetically. Miami Project researcher, Dr. Daniel Liebl is interested in determining the genetic mechanisms by which cells regenerate and the effect that guidance molecules may have on repelling or attracting growth. By understanding the machinery by which axons regenerate, researchers hope to become better equipped to design specific therapies to promote regrowth.

Recently, growth promoting factors, or neurotrophins, placed within the spinal cord were shown to help regenerating axons leave a Schwann cell bridge. In this study, Dr. Oudega and his colleagues placed two neurotrophins in the spinal cord beyond a Schwann cell bridge. Their results indicate that the neurotrophins helped the axons exit the bridge and penetrate the host spinal cord. While it is not yet known, this combination of neurotrophins may either directly act on the axons to promote regeneration or may act indirectly by altering the inhibitory environment of the spinal cord. In striving for successful regeneration, scientists agree that a combination of strategies to promote regrowth and abate inhibitory factors will most likely be needed for a cure for paralysis after SCI.