The human body has an incredible ability to recover from serious injury. One major exception is the spinal cord. In the case of severe trauma, the fragile neuronal branches that carry electrical signals up and down the spinal column can be severed. Unlike other types of nerve cells, these branches, known as axons, have a limited ability to regenerate when damaged. To make matters worse, the surrounding proteins seal off the site of the injury, cutting off any potential reconnection. But, a trio of new strategies suggest that cell and gene therapy may hold the key for repairing these fragile connections and restoring motor function in patients with spinal injuries.
In November of 2017, a team from the University of Guelph in Canada discovered that the gecko tail contains a type of stem cell, called radial glia, that proliferates in response to injury and has the ability to regenerate new spinal cord. The study, published in The Journal of Comparative Biology, posits that this regenerative quality may one day be harnessed to help people with spinal cord injuries.
In March, scientists at the O’Donnell Brain Institute at UT Southwestern Medical Center identified a “genetic trigger” with potential to improve recovery from brain and spinal cord injuries. By overexpressing a gene in mice with spinal cord injuries, the team was able to increase the number of astrocytes—cells that support the response to injury and infection in the central nervous system. This increased number of astrocytes resulted in smaller scars and may one day be used to kick-start the healing process in the brain and central nervous system.
And most recently, researchers at the University of California, San Diego Translational Neuroscience Institute reported in Nature Medicine that they were able to maintain and integrate transplanted stem cells inside the injured spines of monkeys. Using a number of immunosuppressive drugs, the team was able to maintain the transplanted cells over a period of nine-months. Over the course of that time, the transplants formed extensive new synaptic connections with the monkeys’ central nervous systems and restored motor function.