Researchers find the incident commander in the brain's defence system

December 8, 2016, Aarhus University
Researchers are close to finding the mechanisms in the brain that contribute to tissue damage. Credit: Line Reinert

Imagine seeing a building on fire. You grab the phone and call the fire service. What happens next can be compared to the discovery made by researchers from Aarhus University. They have discovered that a specific type of cell in the brain, microglia, acts as the incident commander in the defence against the invading virus, for example a herpes virus.

In cases of viral infection in the brain, this cell type coordinates reinforcements. It recruits additional microglia to the area, which in turn warns the neighbouring that something dangerous is happening. These cells are called astroglia and neurons.

After this, the 'fire' is put out, and 'medical help' is called in via proteins, so the cells that have been injured or killed can be removed.

"Viruses which travel via into the brain are recognised by several types of cells, though not all cells are able to defend themselves against the infection. But microglia can, and through an alarm system (cGAS/STING), they are able to initiate a very strong immune reaction and suppress the virus," explains one of the researchers behind the discovery, Line Reinert from the Department of Biomedicine at Aarhus University.

The results have just been published in Nature Communications, and on the basis of the new knowledge the researchers hope to be able to contribute to new and better treatment of brain diseases such as multiple sclerosis, Alzheimer's disease and potentially also psychiatric disorders.

"We have identified and described a communication network that begins in the brain, when the cGAS/STING alarm system is activated. This new knowledge can potentially be utilised to prevent other types of diseases of the brain, where the same is either not activated or is activated too much," says Line Reinert.

The next step is to look at how damage to the brain occurs during infections and other diseases, and examine which mechanisms the brain uses to find the balance between the good and harmful aspects of the immune system.

"The brain is an organ which cannot withstand much damage. So it must therefore have, on the one hand, defence mechanisms against infections and, on the other hand, not utilise these too strongly. If microglia are activated too much, they do not only suppress the virus, but also damage some of the tissue. We are now working to understand this," says Søren Riis Paludan, who has led the project group, which has also involved other research groups from Denmark and abroad.

Explore further: Study explains mechanisms behind glioblastoma influence on the immune system

More information: Line S. Reinert et al, Sensing of HSV-1 by the cGAS–STING pathway in microglia orchestrates antiviral defence in the CNS, Nature Communications (2016). DOI: 10.1038/ncomms13348

Related Stories

Study explains mechanisms behind glioblastoma influence on the immune system

September 12, 2016
Glioblastomas exert an influence on the microglia, immune cells of the brain, which causes them to stimulate cancer growth rather than attacking it. In a study published in the journal Nature Immunology, an international ...

Breakthrough in understanding of brain development: Immune cell involvement revealed

August 25, 2016
Microglia are cells that combat various brain diseases and injuries by swallowing foreign or disruptive objects and releasing molecules that activate repair mechanisms. Recent findings have suggested these brain cells are ...

Experimental drug shows promise in treating Alzheimer's disease

October 25, 2016
An experimental drug shows promise in treating Alzheimer's disease by preventing inflammation and removing abnormal protein clumps in the brain that are associated with the disease, suggests a study in mice presented at the ...

Researchers discover neuroprotective role of immune cell

July 22, 2014
A type of immune cell widely believed to exacerbate chronic adult brain diseases, such as Alzheimer's disease and multiple sclerosis (MS), can actually protect the brain from traumatic brain injury (TBI) and may slow the ...

Seasonal allergies could change your brain

August 8, 2016
Hay fever may do more than give you a stuffy nose and itchy eyes, seasonal allergies may change the brain, says a study published in the open-access journal Frontiers in Cellular Neuroscience.

New discovery: This is why we do not constantly get ill despite viruses and bacteria

December 1, 2015
New research breaks with existing knowledge about how our immune system works. Experiments at Aarhus University have shown how the body mobilises a hitherto unknown defence against viruses and bacteria. This also explains ...

Recommended for you

A peek into the interplay between sleep and wakefulness

July 20, 2018
Sleep is an autonomic process and is not always under our direct, voluntary control. Awake or asleep, we are basically under the regulation of two biological processes: sleep homeostasis, commonly known as 'sleep pressure', ...

Paralyzed mice with spinal cord injury made to walk again

July 19, 2018
Most people with spinal cord injury are paralyzed from the injury site down, even when the cord isn't completely severed. Why don't the spared portions of the spinal cord keep working? Researchers at Boston Children's Hospital ...

Neural inflammation plays critical role in stress-induced depression

July 19, 2018
A group of Japanese researchers has discovered that neural inflammation caused by the innate immune system plays an unexpectedly important role in stress-induced depression. This insight could potentially lead to the development ...

Scientists uncover the role of a protein in production and survival of myelin-forming cells

July 19, 2018
The nervous system is a complex organ that relies on a variety of biological players to ensure daily function of the human body. Myelin—a membrane produced by specialized glial cells—plays a critical role in protecting ...

Understanding the neuroscience of binge drinking

July 19, 2018
A new study from researchers at Columbia University Irving Medical Center found that binge drinking impairs working memory in the adolescent brain. The study, in mice, explains why teenagers who binge drink are 15 times more ...

Neurons can carry more than one signal at a time

July 18, 2018
Back in the early days of telecommunications, engineers devised a clever way to send multiple telephone calls through a single wire at the same time. Called time-division multiplexing, this technique rapidly switches between ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.