Gut Bacteria Trick Your Immune System into Autoimmunity

Gut Bacteria Trick Your Immune System into Autoimmunity

Stepping into the inter-workings of our body systems is like stepping into a modern factory assembling a large and complex machine.  The interplay between something like a simple bacterium in our colon and an on-site immune cell can end up triggering autoimmune diseases like rheumatoid arthritis in our joints.  What goes on in one system does not always stay in that area geographically; often its effects have many downstream consequences.  In a study out of Ohio State University on autoimmune arthritis, researchers report how, using mice, they have traced back specific immune cells to the gut’s immune system.

With a reported 18 million and growing worldwide suffering from rheumatoid arthritis as well as other autoimmune conditions, medicine is constantly searching for better understanding of the basic pathway of autoimmunity so we can develop better therapies.  Research has shown that, in mice, an immune cell call a Tfh17 (T follicular helper 17) circulate in those with autoimmune diseases, and that higher numbers correlate with more severe symptoms.

The Tfh17 cell and its similar counterpart in humans has been a mystery, due to its mixed characteristics.  Normally, follicular helper cells (Tfh) stay put in the lymphatic follicles rather than traveling through the blood stream.  Normally, Th17 cells have particularly characteristics of traveling in the blood stream and causing more inflammation.   The combination of the Tfh and Th17 subtypes, then, seems to create immune cells with greater potential to cause autoimmunity.

So far, this seems like an immunology lesion without an application until the researchers point out that these combination Tfh17 cells appear to originate from Peyer’s Patches in the GI tract.  These collections of immune surveillance cells in the walls of our intestines monitor what goes through our GI tract and what tries to cross into our bloodstream from the gut.    The further excitement came from determining the interaction between some normally benign bacteria in the gut microbiome and the development of these cells.

Commensal bacteria, ones that live in our gut without causing any harm or disease, normally keep our gut healthy by preventing the growth of bad bacteria.  In the cases of Tfh17 cell development the bacteria trigger an increase in their numbers.  These cells can then leave the gut’s Peyer’s Patches and travel to other body locations where they cause problems.

As we wait for further research which indicates how we can modify this process to prevent or treat autoimmune diseases, we will continue to work on overall gut health in our functional medicine clinic.  Between research like this indicating a connection between gut bacteria and autoimmunity, we know other studies demonstrate links between leaky gut and autoimmunity.  In helping our patients restore healthier, more abundant lives after autoimmune diagnoses, we help them remove toxic, infectious, and food contributors to autoimmune triggers in their guts.  This goes a long way in setting their bodies on a path to healing.

 

Original Article:

Tingting Fan, Chi Tai, Kiah C. Sleiman, Madeline P. Cutcliffe, Haram Kim, Ye Liu, Jianying Li, Gang Xin, Mollyanna Grashel, Laurie Baert, Chinwe Ekeocha, Paige Vergenes, Svetlana Lima, Wan-Lin Lo, Judith Lin, Beatriz Hanaoka, Trevor N. Tankersley, Min Wang, Xuan Zhang, George C. Tsokos, Wael Jarjour, Randy Longman, Hsin-Jung Joyce Wu. Aberrant T follicular helper cells generated by TH17 cell plasticity in the gut promote extraintestinal autoimmunity. Nature Immunology, 2025; 26 (5): 790 DOI: 10.1038/s41590-025-02125-7

 

Thanks to Science Daily:

Ohio State University. “Explaining the link between ‘good’ gut bacteria and rheumatoid arthritis.” ScienceDaily. ScienceDaily, 1 May 2025. <www.sciencedaily.com/releases/2025/05/250501163952.htm>.

 

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Sanctuary Functional Medicine, under the direction of Dr Eric Potter, IFMCP MD, provides functional medicine services to Nashville, Middle Tennessee and beyond. We frequently treat patients from Kentucky, Alabama, Mississippi, Georgia, Ohio, Indiana, and more... offering the hope of healthier more abundant lives to those with chronic illness.