Modulation of immune responses by bile acid receptor agonists in myasthenia gravis.

Bile acids bind to multiple receptors, including Takeda G protein-coupled receptor 5 (TGR5) and farnesoid-X-receptors alpha (FXRα). We compared the response of PBMCs to the activation of these receptors in healthy controls and myasthenic patients. We found that TGR5 is a more potent negative regulator of T cell cytokine response than FXRα in both groups. In contrast, TGR5 and FXRα agonists elicit distinct B cell responses in myasthenia compared to controls, specifically on the frequency of IL-6+ B cells and regulatory B cells, as well as IL-10 secretion from PBMCs. We propose that TGR5 is a potential therapeutic target in myasthenia.