Biomarkers of multiple sclerosis disease course in the blood and in the gut

Multiple sclerosis (MS) is an inflammatory, degenerative disease of the central nervous system with a heterogeneous disease course. Previous studies indicate a role of the gut microbial community (microbiota) in the pathogenesis of MS. However, a lot remains unclear as most studies with MS patients were relatively small-scale, cross-sectional and considering few possible confounders. There is a need for large prospective studies of the gut microbiota in relation to disease activity in MS while taking into account important confounders relative to the microbiome. Furthermore, the disease course of MS is largely unpredictable and biomarkers that correlate with clinical and radiological outcomes are lacking. We will address these scientific gaps by performing a time-course analysis of the composition of the gut microbiome in relation to (para-)clinical outcome measures of MS both in the short-term (e.g. investigating potential transient gut microbiota changes during relapses) as in the long-term (e.g. exploring associations between gut microbiota variation and disability, serum markers of inflammation, MRI measures in subsequent years). We aim to substantiate the hypothesis that the gut microbiota and MS pathogenesis are linked and to assess whether the gut microbiome harbors potential biomarkers which could be developed into predictive and/or diagnostic biomarkers for clinical disease course outcomes in MS.