Engineered probiotic may aid in multiple sclerosis treatment.

Engineered probiotic may aid in multiple sclerosis treatment.

Harnessing the Power of Gut Bacteria to Treat Autoimmune Diseases

Researchers are looking into using gut bacteria to treat autoimmune diseases such as multiple sclerosis.

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Gut bacteria have long been recognized as vital to overall health. Now, a groundbreaking study suggests that these microbes could even play a role in treating autoimmune diseases such as multiple sclerosis (MS). Researchers at Boston’s Brigham and Women’s Hospital have successfully bioengineered a probiotic that effectively suppresses autoimmunity in the brain, at least in animal studies.

Autoimmune diseases occur when the immune system mistakenly attacks healthy cells in the body. In the case of MS, the immune system targets and destroys the protective myelin sheath around nerve cells, leading to a range of debilitating symptoms. The study, published in the journal Nature, highlights the potential of probiotic therapy in treating MS and other autoimmune diseases that affect the central nervous system.

Dr. Francisco Quintana, a lead author of the study and a professor of neurology at Brigham and Women’s Hospital, envisions a revolution in chronic disease treatment with the use of engineered probiotics. He explains, “When a drug is taken, its concentration in the bloodstream peaks after the initial dose, but then its levels go down. However, if we can use living microbes to produce medicine from within the body, they can keep producing the active compound as needed, which is essential when we consider lifelong diseases that require constant treatment.”

Breaking Down the Mechanism

In their study, Quintana and his colleagues engineered probiotic bacteria to produce lactate. This lactate then activates a biochemical pathway used by dendritic cells, which are immune cells found in both the brain and the gastrointestinal tract. By activating this pathway, the probiotic effectively stops other immune cells from attacking the body.

Quintana likens this mechanism to a “brake” for the immune system, one that is dysfunctional in individuals with autoimmune diseases. He explains, “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.”

The researchers injected mice with the bioengineered bacteria and observed a significant reduction in symptoms of an MS-like disease. This suggests that there is potential for using gut bacteria to prevent the immune system from attacking the body, not only in MS but also in other autoimmune conditions.

The Gut-Brain Connection

The link between the gut and the brain may seem far-fetched, but Quintana explains that the microbiome fine-tunes our immune system. In people with autoimmune diseases, this regulation goes awry. Interestingly, the lymphocytes responsible for brain damage in MS patients originate in the gut. By halting their migration from the gut to the brain, the bioengineered probiotic offers a novel approach to addressing autoimmune diseases.

While the dendritic cells in the gut and brain are not identical, they seem to share similar mechanisms of control. This realization opens up new possibilities for treatments that target the gut microbiome to modulate immune responses and protect against autoimmune diseases.

Manipulating the Gut Microbiome for Therapy

Manipulating the gut microbiome is an area of increasing interest in the field of medical research. In a 2021 study, Quintana and his team modified a strain of yeast found in the gut to treat symptoms of inflammatory bowel syndrome. By producing therapeutic compounds within the body, engineered probiotics could potentially provide targeted and effective treatments with limited side effects.

It’s worth noting that the U.S. Food and Drug Administration (FDA) has already approved over 20 drugs to treat MS, all of which modulate the immune system in some way. The findings of this study align with the trend of exploring alternative, more direct approaches to counter autoimmune diseases. Dr. J. William Lindsey, the director of the Division of Multiple Sclerosis and Neuroimmunology at the University of Texas Health Science Center, believes that the study offers exciting potential for treatments that can have significant benefits while minimizing side effects.

The road to utilizing gut bacteria as a treatment for autoimmune diseases is still long, with further research and clinical trials necessary. However, the development of bioengineered probiotics underscores the immense potential that lies within the gut microbiome. As we continue to unravel the complex relationship between our gut and our overall health, it becomes clear that harnessing the power of these tiny organisms could revolutionize the treatment of chronic diseases like multiple sclerosis.