Up to now, spinal cord injuries caused by accidents have been considered absolutely irreparable. This is because these accidents damage nerve fibers called axons.
These axons carry information from the brain to the muscles and back again. In spinal cord injuries, that communication is interrupted and since axons of the central nervous system can't grow back, it can not be restored. This results in paralysis for life.
Now, scientists from the Department for Cell Physiology at Ruhr-Universität Bochum (RUB) headed by Professor Dietmar Fischer have succeeded for the first time in getting paralyzed mice to walk again by manipulating a genetically-engineered protein called hyper-interleukin-6.
“This is a so-called designer cytokine, which means it doesn’t occur like this in nature and has to be produced using genetic engineering,” explained in a statement Fischer.
Using viruses, the team was able to transport the designer protein to specific nerve cells, so-called motoneurons, and release it in a controlled manner.
“Thus, gene therapy treatment of only a few nerve cells stimulated the axonal regeneration of various nerve cells in the brain and several motor tracts in the spinal cord simultaneously,” said Fischer.
Two to three weeks
“Ultimately, this enabled the previously paralyzed animals that received this treatment to start walking after two to three weeks. This came as a great surprise to us at the beginning, as it had never been shown to be possible before after full paraplegia," continued Fischer.
Now, Fischer and his team are looking into optimizing the administration of hyper-Interleukin-6 and exploring whether the protein can work even if the injury occurred several weeks prior.
This aspect would be particularly relevant for application in humans,” explained Fischer. “We are now breaking new scientific ground. These further experiments will show, among other things, whether it will be possible to transfer these new approaches to humans in the future.”