Nav: Home

Mouse study points way to shut down harmful immune response in lupus

August 17, 2016

DURHAM, N.C. - Molecules that scavenge debris from dying cells appear to halt the cycle of chronic inflammation in lupus, while also enhancing the body's ability to combat flu, according to Duke Health studies in mice.

The molecules, called polymers, have commonly been used in gene-transfer experiments because they bind to the nucleic acid in DNA and RNA. When deployed directly in mice with lupus or an acute flu infection, the polymers home in on the DNA and RNA refuse from dying cells, halting the damaging immune attack.

"This debris left by dead cells can mistakenly signal to the body that there is an infection that warrants immune action, triggering the innate immune system," said Bruce A. Sullenger, Ph.D., director of the Duke Translational Research Institute. Sullenger is senior author of a study published online this week in the Proceedings of the National Academy of Sciences.

"By selectively targeting the source of the immune activation rather than shutting off the innate immune system downstream, these nucleic acid scavengers are able to limit pathological inflammation without compromising one's ability to fight a viral infection," Sullenger said.

Pathological inflammation, a major cause of illness and death around the world, is a hallmark of autoimmune diseases, including lupus and diabetes, as well as chronic conditions such as heart disease and some cancers. It also fuels the organ failure associated with severe infectious diseases such as Ebola or even flu.

Current therapies to treat pathological inflammation generally focus on quieting the overactive immune response, but in suppressing the immune system, patients are vulnerable to severe infections arising from other sources.

Intrigued by the ability of certain polymers to mop up DNA and RNA for gene transfer, Sullenger and colleagues tested the idea that these chemical compounds might also be effective targeting such nucleic acids as they arise in cell death.

"Essentially what you have in an autoimmune disease is a vicious cycle," said lead author Eda K. Holl, Ph.D., assistant professor in Duke's Department of Surgery. "Our goal was to break this cycle at its onset. What we saw in animals with lupus when we used these compounds was a dramatic reduction in inflammation, which gave the body a chance to heal."

Sullenger and Holl said the approach was further tested to see if it compromised the mice's ability to fight outside infections. When they exposed the treated mice to the influenza virus, the animals recovered from the illness even better than healthy mice infected with flu that had not undergone the treatment.

"This approach has the potential to treat a wide range of inflammatory conditions --from lupus to diabetes to even obesity," Sullenger said.

He said the research team is continuing studies in animal models and working to start a company to develop and commercialize the scavenger approach.
In addition to Sullenger and Holl, study authors from Duke include Kara L. Shumansky, Angela D. Burnette, Christopher J. Sample, and Elizabeth A. Ramsburg. They were joined by Luke B. Borst of N.C. State University.

The work received support from the National Institutes of Health (R56 AI093900, R01 HL06522, P01 HL11626, F32 DK094543) and the Coulter Foundation.

Duke University Medical Center

Related Immune System Articles:

The immune system may explain skepticism towards immigrants
There is a strong correlation between our fear of infection and our skepticism towards immigrants.
New insights on how pathogens escape the immune system
The bacterium Salmonella enterica causes gastroenteritis in humans and is one of the leading causes of food-borne infectious diseases.
Understanding how HIV evades the immune system
Monash University (Australia) and Cardiff University (UK) researchers have come a step further in understanding how the human immunodeficiency virus (HIV) evades the immune system.
Carbs during workouts help immune system recovery
Eating carbohydrates during intense exercise helps to minimise exercise-induced immune disturbances and can aid the body's recovery, QUT research has found.
A new model for activation of the immune system
By studying a large protein (the C1 protein) with X-rays and electron microscopy, researchers from Aarhus University in Denmark have established a new model for how an important part of the innate immune system is activated.
More Immune System News and Immune System Current Events

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Teaching For Better Humans
More than test scores or good grades — what do kids need to prepare them for the future? This hour, guest host Manoush Zomorodi and TED speakers explore how to help children grow into better humans, in and out of the classroom. Guests include educators Olympia Della Flora and Liz Kleinrock, psychologist Thomas Curran, and writer Jacqueline Woodson.
Now Playing: Science for the People

#535 Superior
Apologies for the delay getting this week's episode out! A technical glitch slowed us down, but all is once again well. This week, we look at the often troubling intertwining of science and race: its long history, its ability to persist even during periods of disrepute, and the current forms it takes as it resurfaces, leveraging the internet and nationalism to buoy itself. We speak with Angela Saini, independent journalist and author of the new book "Superior: The Return of Race Science", about where race science went and how it's coming back.