Researchers have developed a genetically engineered probiotic that targets autoimmunity in the brain, a key factor in diseases like multiple sclerosis. The probiotic bacteria produce lactate to regulate immune responses, reducing brain inflammation in mouse models with fewer side effects than standard therapies.
In a new study, researchers demonstrated the treatment’s potential using preclinical models of these diseases, finding that the technique offered a more precise way to target brain inflammation with reduced negative side effects compared to standard therapies.
“The mechanism we found is like a brake for the immune system,” said Quintana. “In most of us, it’s activated, but in people with autoimmune diseases, there are problems with this brake system, which means the body has no way to protect itself from its own immune system.” They tested their probiotic in mice with a disease closely resembling MS, and they found that even though the bacteria live in the gut, they were able to reduce the effects of the disease in the brain. They did not find the bacteria in the bloodstream of the mice, suggesting that the effect they observed was a result of biochemical signaling between cells in the gut and in the brain.