Boosting number of anti-inflammatory immune cells may prevent brain damage, study shows

In a recent study, scientist found when specialized anti-inflammatory immune cells within the brains of mice were increased, brain damage caused from brain injuries was reduced.

The study, published in the journal Nature Immunology, was conducted by researchers from the Babraham Institute Immunology research program in Cambridge, United Kingdom. According to the study, a leading cause of cognitive impairment due to brain injury is inflammation in the brain which causes the brain to swell, sometimes resulting in permanent damage. The study was led by Adrian Linston, PhD, a professor at the Babraham Institute and Matthew Holt, PhD, professor at the Institute for Research and Innovation in Health at the University of Porto in Porto, Portugal.

In their study, Linston, Holt, and their team of researchers set out to discover how increasing a certain immune cell within the brain affects brain inflammation. To do so, the study observed the effects of increasing the number of regulatory T cells in the brain.

 “Our bodies have their own anti-inflammatory response, regulatory T cells, which have the ability to sense inflammation and produce a cocktail of natural anti-inflammatories,” said Liston in a statement. “Unfortunately, there are very few of these regulatory T cells in the brain, so they are overwhelmed by the inflammation following an injury. We sought to design a new therapeutic to boost the population of regulatory T cells in the brain, so that they could manage inflammation and reduce the damage caused by traumatic injury.”

Upon investigation, researchers found the reason why there are so few regulatory T cells in the brain was related to the molecule interleukin 2, or IL2. According to the study, the body has a limited supply of IL2, which are a crucial survival molecule. With this new insight, scientists decided to increase the production of IL2, therefore allowing more regulatory T cells to survive.  

Researchers then tested this process on mice. They gave mice a carefully controlled brain injury and then treated them with the IL2 treatment. To test their cognitive function, researchers had the mice perform cognitive tests. Their results showed that the intervention was effective in reducing inflammation caused by the mice’s brain injuries. In addition, the mice who received the treatment were also shown to have improved cognitive function.

Although more research is necessary, this study’s results suggest that brain damage could be reduced after injury by leveraging the IL2 molecule.

“By understanding and manipulating the immune response in the brain, we were able to develop a gene delivery system for IL2 as a potential treatment for neuroinflammation,” said Liston. “With tens of millions of people affected every year, and few treatment options, this has real potential to help people in need. We hope that this system will soon enter clinical trials [which is] essential to test whether the treatment also works in patients."