Can Nanoparticle Injections Prevent Spinal Cord Injury Paralysis?

July 17, 2019 – Co-opting the immune response as a therapeutic approach to a traumatic injury to the spine is seen by researchers at the University of Michigan as an “EpiPen” for the central nervous system, and brain.

Not familiar with the EpiPen? Carried by tens of thousands who may experience anaphylaxis in response to an allergy, these injectors save lives. But who would have thought that you could use such a device, albeit not containing epinephrine, to deal with spinal cord injury?

University of Michigan researchers replaced the normal contents of the EpiPen with injectable nanoparticles to stop immune cells from reaching the site of a spinal cord injury. The particles, about the size of cell debris, and negatively charged, are non-pharmaceutical and therefore produce no side effects. By blocking immune cells from a trauma site, the researchers were trying to stop the natural process of inflammation, often a consequence of these cells when they arrive. The researchers found that their nanoparticles didn’t block all immune cells, just most of the ones that were inflammatory, letting ones that support tissue regrowth to get through.

The research results appear in the July 8, 2019 issue of PNAS, Proceedings of the National Academy of Sciences of the United States of America. The authors describe the administration of lactide-co-glycolide nanoparticles by site injection and the results which show a reduction in the number of pro-inflammatory immune cells. The outcome showed a 4-fold decline in immune cell infiltration and a 3-fold reduction in gliotic scarring. The nanoparticle injections increased the number of regenerating axons and myelination by up to 40% helping to restore locomotor function.

For the 250,000 to 500,000 people who each year suffer a spinal cord injury, this EpiPen approach could dramatically improve outcomes.

According to the World Health Organization, people who suffer a spinal cord injury are two to five times more likely to suffer a premature death. And such injuries carry substantial individual and societal costs. Those most at risk are young males between ages 20 and 29 with the ratio of male-to-female at least 2:1 among adults.

Treating spinal cord injury, however, has a checkered history with most patients experiencing paralysis in either the lower limbs, paraplegia or in all four, quadriplegia. And steroidal treatments at the time of the injury and after have produced complications such as sepsis, gastrointestinal bleeding, and blood clots.

Immune response complications are a known problem in medicine. In spinal cord injury as well as for chronic inflammatory responses the most common treatments have failed to deliver a long-term positive outcome. As one who suffers from osteoarthritis, a chronic inflammatory disease, I have periodically received cortisone injections to help reduce pain and inflammation. And today I use cannabis in the form of CBD oil to mitigate the pain associated with the condition.

But what about this nanoparticle EpiPen approach to treat my inflammatory disease, not just spinal cord trauma?

Diseases are known to present inflammation. Not just osteoarthritis, but rheumatoid arthritis, lupus, multiple sclerosis, and many others cause white blood cells, antibodies, cytokines, and other immunological chemicals to respond to the area of the body where the condition occurs. The problem for medical researchers is that there are dozens of immunological and inflammatory molecules and pathways throughout our bodies through which these protective agents interact with an injury site or disease presence. The loops and feedbacks of these pathways mean inflammation can turn on and off in any number of ways. For chronic inflammatory diseases, the response, however, doesn’t switch off and the swelling and pain remain a constant. Inflammatory responses include hives, itching, swelling, pain, and even anaphylaxis.

It will be interesting to follow this early research into nanoparticle injections. If they should prove effective in human trials, could this become a treatment standard for chronic inflammatory response as well as traumatic spinal cord or even brain injury? If so, this research at the University of Michigan could prove to be a significant treatment breakthrough.