After receiving a single injection with synthetic nanofibres, scientists discovered that mice who had suffered spinal cord injuries and left their hind legs paralysed were able to walk again.
This therapy uses designer molecules to mimic the environment of the spine cord and trigger cells to heal and regenerate. The research team hopes to start patient trials in two years.
Professor Samuel Stupp from Northwestern University in Chicago led the study and believes it could lead to the development of the first effective treatment for spinal injuries. He said, "I'm very excited and confident this will help patients," adding that "We are going straight the Food and Drug Administration to begin the process to get this new therapy approved to use in humans. Patients currently have very few options."
An estimated 50,000 people live in the UK with a spinal injury. Every year, approximately 2,500 people are injured. There are no current treatments for spinal cord injury.
A new class of smart materials was used to replicate the extracellular matrix of the body, a non-cellular component of all tissue that was previously considered an inert scaffold. There is increasing evidence that the matrix plays an important role in the body’s repair process via biochemical and biomechanical cues. This is what Stupp, his colleagues and I were trying to replicate.
They used supramolecular polmers, which are made of weakly bonded structural unit that vibrate and wiggle around, to accomplish this. This allows them to communicate with cellular receptors, which are constantly moving, and find and communicate with them.
These polymers can dissolve in water and be administered as a liquid injection. However, when they come in contact with living tissue, they instantly transform into a gel which remains at the injury site.
Stupp stated that cells "immediately move into the water-filled spaces and become tangled in nanofibers." "These fibres signal to the cells that they are ready for repair over a period of two to three weeks."
Science published a paper that showed how spinal injury victims were able to walk again after receiving a single injection with the synthetic matrix. Study also showed that treatment caused the regrowth of severed extensions of neuronal nerves (known as axons); a decrease in scar tissue which can be a barrier to repair; and the formation of new blood vessels. This improved survival rate for motor neurons.
Once the treatment is complete, it is broken down into nutrients within 12 weeks. Then, the substance is eliminated completely from the body.
This breakthrough comes after a series of high-profile studies on spinal cord injury over the past decade. These include a study that suggested that electric implants could aid regeneration, and another that suggested that stem cell injections could be a promising treatment. Stupp said that his team's approach would deliver this time.
He said, "It doesn't involve using cells, it does not involve electricity or invasive devices that could be dangerous", he added. The therapy is easily translatable, which is why this idea could be different than previous ones. It is a very simple molecule. We are so excited about this.
The FDA will allow the team to conduct a human study next year. They hope to begin this trial in two years.
