Meta-analysis identifies common gut microbiota signatures in patients with multiple sclerosis

Background: Previous studies have identified a large number of distinct microbial taxa that are different between patients with multiple sclerosis (MS) and controls. However, interpretating findings on MS-associated microbiome is challenging as results do not completely concur and studies have included relatively few individuals. To date, it is unclear whether there is a common gut microbial signature in patients with MS across studies. To identity the most common compositional differences of the gut microbiome in MS versus healthy controls, we performed a meta-analysis. This was based on 16S rRNA gene sequences from seven published studies, comprising a total of 524 adult patients with MS and control subjects. Results: We found that although alpha and beta diversity did not differ between MS and controls, a lower relative abundance of Prevotella and a dysbiosis of numerous genera within the Clostridia class were reproducibly associated with MS. Additionally, network analysis revealed that the recognized negative Bacteroides-Prevotella correlation in controls was disrupted in MS. immunosuppressive agents normalized MS-associated microbiome Prevotella to a similar level as healthy controls. Conclusions: Our meta-analysis revealed reproducible gut microbiome signatures in MS across geographically diverse studies. These findings form the basis for future novel therapeutic approaches and possibly enhanced MS recognition/diagnosis by targeting common microbiome signatures.