Nav: Home

An 'EpiPen' for spinal cord injuries

July 11, 2019

ANN ARBOR--An injection of nanoparticles can prevent the body's immune system from overreacting to trauma, potentially preventing some spinal cord injuries from resulting in paralysis.

The approach was demonstrated in mice at the University of Michigan, with the nanoparticles enhancing healing by reprogramming the aggressive immune cells--call it an "EpiPen" for trauma to the central nervous system, which includes the brain and spinal cord.

"In this work, we demonstrate that instead of overcoming an immune response, we can co-opt the immune response to work for us to promote the therapeutic response," said Lonnie Shea, the Steven A. Goldstein Collegiate Professor of Biomedical Engineering.

Trauma of any kind kicks the body's immune response into gear. In a normal injury, immune cells infiltrate the damaged area and clear debris to initiate the regenerative process.

The central nervous system, however, is usually walled off from the rough-and-tumble of immune activity by the blood-brain barrier. A spinal cord injury breaks that barrier, letting in overzealous immune cells that create too much inflammation for the delicate neural tissues. That leads to the rapid death of neurons, damage to the insulating sheaths around nerve fibers that allow them to send signals, and the formation of a scar that blocks the regeneration of the spinal cord's nerve cells.

All of this contributes to the loss of function below the level of the injury. That spectrum includes everything from paralysis to a loss of sensation for many of the 12,000 new spinal injury patients each year in the United States.

Previous attempts to offset complications from this immune response included injecting steroids like methylprednisolone. That practice has largely been discarded since it comes with side effects that include sepsis, gastrointestinal bleeding and blood clots. The risks outweigh the benefits.

But now, U-M researchers have designed nanoparticles that intercept immune cells on their way to the spinal cord, redirecting them away from the injury. Those that reach the spinal cord have been altered to be more pro-regenerative.

With no drugs attached, the nanoparticles reprogram the immune cells with their physical characteristics: a size similar to cell debris and a negative charge that facilitates binding to immune cells. In theory, their nonpharmaceutical nature avoids unwanted side effects.

With fewer immune cells at the trauma location, there is less inflammation and tissue deterioration. Second, immune cells that do make it to the injury are less inflammatory and more suited to supporting tissues that are trying to grow back together.

"Hopefully, this technology could lead to new therapeutic strategies not only for patients with spinal cord injury but for those with various inflammatory diseases," said Jonghyuck Park, a U-M research fellow working with Shea.

Previous research has shown success for nanoparticles mitigating trauma caused by the West Nile virus and multiple sclerosis, for example.

"The immune system underlies autoimmune disease, cancer, trauma, regeneration--nearly every major disease," Shea said. "Tools that can target immune cells and reprogram them to a desired response have numerous opportunities for treating or managing disease."
-end-
The research, published in the current issue of Proceedings of the National Academy of Sciences, was supported by The National Institutes of Health. Shea is also the William and Valerie Hall Chair of Biomedical Engineering and a professor of chemical engineering. Study abstract: https://www.pnas.org/content/early/2019/07/02/1820276116

The Shea Lab: https://shearesearch.engin.umich.edu/

University of Michigan

Related Immune System Articles:

Too much salt weakens the immune system
A high-salt diet is not only bad for one's blood pressure, but also for the immune system.
Parkinson's and the immune system
Mutations in the Parkin gene are a common cause of hereditary forms of Parkinson's disease.
How an immune system regulator shifts the balance of immune cells
Researchers have provided new insight on the role of cyclic AMP (cAMP) in regulating the immune response.
Immune system upgrade
Theoretically, our immune system could detect and kill cancer cells.
Using the immune system as a defence against cancer
Research published today in the British Journal of Cancer has found that a naturally occurring molecule and a component of the immune system that can successfully target and kill cancer cells, can also encourage immunity against cancer resurgence.
First impressions go a long way in the immune system
An algorithm that predicts the immune response to a pathogen could lead to early diagnosis for such diseases as tuberculosis
Filming how our immune system kill bacteria
To kill bacteria in the blood, our immune system relies on nanomachines that can open deadly holes in their targets.
Putting the break on our immune system's response
Researchers have discovered how a tiny molecule known as miR-132 acts as a 'handbrake' on our immune system -- helping us fight infection.
Decoding the human immune system
For the first time ever, researchers are comprehensively sequencing the human immune system, which is billions of times larger than the human genome.
Masterswitch discovered in body's immune system
Scientists have discovered a critical part of the body's immune system with potentially major implications for the treatment of some of the most devastating diseases affecting humans.
More Immune System News and Immune System Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Listen Again: Meditations on Loneliness
Original broadcast date: April 24, 2020. We're a social species now living in isolation. But loneliness was a problem well before this era of social distancing. This hour, TED speakers explore how we can live and make peace with loneliness. Guests on the show include author and illustrator Jonny Sun, psychologist Susan Pinker, architect Grace Kim, and writer Suleika Jaouad.
Now Playing: Science for the People

#565 The Great Wide Indoors
We're all spending a bit more time indoors this summer than we probably figured. But did you ever stop to think about why the places we live and work as designed the way they are? And how they could be designed better? We're talking with Emily Anthes about her new book "The Great Indoors: The Surprising Science of how Buildings Shape our Behavior, Health and Happiness".
Now Playing: Radiolab

The Third. A TED Talk.
Jad gives a TED talk about his life as a journalist and how Radiolab has evolved over the years. Here's how TED described it:How do you end a story? Host of Radiolab Jad Abumrad tells how his search for an answer led him home to the mountains of Tennessee, where he met an unexpected teacher: Dolly Parton.Jad Nicholas Abumrad is a Lebanese-American radio host, composer and producer. He is the founder of the syndicated public radio program Radiolab, which is broadcast on over 600 radio stations nationwide and is downloaded more than 120 million times a year as a podcast. He also created More Perfect, a podcast that tells the stories behind the Supreme Court's most famous decisions. And most recently, Dolly Parton's America, a nine-episode podcast exploring the life and times of the iconic country music star. Abumrad has received three Peabody Awards and was named a MacArthur Fellow in 2011.