The human microbiota is composed of diverse forms of microorganisms that live on or in us and plays a crucial role in the health and development. Commensal species that reside in the intestine particularly influence host physiology at local and systemic levels. Multiple sclerosis (MS) is a debilitating autoimmune disorder of the central nervous system for which there is currently no cure. While the cause of MS is unknown, there is a growing body of evidence suggesting that the microbiota can play both pathogenic and protective roles in disease progression. In this review, we provide a brief overview, based on both animal and clinical studies, of the current understanding by which the microbiota may influence MS and discuss opportunities for therapeutic intervention that may alleviate the symptoms associated with this debilitating neuroimmunological disease.
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