Scientists Make Breakthrough in Undoing Spine Injuries

Scientists have made a breakthrough repairing potentially devastating spinal cord injuries—using the body’s own healing process to do it. 

Researchers from the University of California Los Angeles, the Swiss Federal Institute of Technology and Harvard University  identified a specific class of neurons—nerve cells that transmit signals to one-another—which can be key to undoing this damage.

In previous mouse-based research, scientists have been able to get neurons to regenerate, however, they have not been able to translate this regeneration into restoring the ability of mice to walk after a spinal cord injury. 

To solve this problem researchers in the newest study, published Thursday  in the journal Science, looked at a specific spinal cord injury called Brown-Séquard syndrome. 

People with this injury lose their ability to feel sensations on one side of their body due to damage to the spinal cord, which often leads to a loss of one’s ability to walk. 

However, people with this injury can recover their ability to walk, and previous research has found that this may be because neurons in the spinal cord can reach past the injured site, restoring  the ability of the brain to communicate with the muscles.  

Neurons, the researchers found, already have the tools to regenerate on their own. The researchers just needed to find which neurons specifically drove this recovery.

The team found that a specific class of neurons are necessary to communicate within the same general area of the body, or short-distance communication, and which neurons needed to communicate with the brain and their designated area, or long-distance communication. 

After identifying the specific neurons, the researchers tried implanting them into mice with spinal cord injuries and seeing if they integrated enough to restore the mice’s ability to walk. 

However, these neurons were only somewhat able to communicate with their immediate surroundings, and not able to communicate with the brain, leaving the mice still unable to walk.

This prompted the researchers to try exposing the neurons to chemical signals that told the neurons where to go—instead of letting them do as they pleased, they essentially gave the cells a roadmap to the injury sites that needed to be reconnected with the rest of the body. Doing so finally bridged the gap between getting the cells to regenerate and actually restoring the mice’s motor abilities. 

The authors say that their findings could propel more research into repairing spinal cord injuries in humans. While larger mammals are much more complex than mice, their work ​​may help “unlock the framework to achieve meaningful repair of the injured spinal cord and may expedite repair after other forms of central nervous system injury and disease.”