The immunomodulatory roles of the gut microbiome in autoimmune diseases of the central nervous system: Multiple sclerosis as a model

The gut-associated lymphoid tissue is a primary activation site for immune responses to infection and immunomodulation. Experimental evidence using animal disease models suggests that specific gut microbes significantly regulate inflammation and immunoregulatory pathways. Furthermore, recent clinical findings indicate that gut microbes’ composition, collectively named gut microbiota, is altered under disease state. This review focuses on the functional mechanisms by which gut microbes promote immunomodulatory responses that could be relevant in balancing inflammation associated with autoimmunity in the central nervous system. We also propose therapeutic interventions that target the composition of the gut microbiota as immunomodulatory mechanisms to control neuroinflammation. •Studies in murine models indicate the importanceof the gut microbiome regulating CNS autoimmunity.•Gut microbiome analysis of MS patients indicate significant alterations the relative abundances of specific microbial taxa.•Gut-induced immunomodulationcould contribute to the microbiome's regulatory effects on MS.•The cellular mechanisms of immunomodulation triggered by the gut microbiome remain to be elucidated.