Author Subject Treatment Bacterial in MS↑ Bacterial in MS↓ Bacterial in treatment↑ Bacterial in treatment↓ Other results Jangi et al. [128 ] MS HC IFN-β GA Untreated Methanobrevibacter Akkermansia Butyricimonas Prevotella Sutterella Sarcina Tremlett et al. [134 ] Children ≤ 18 MS HC IFN-β GA Untreated (1) No difference in immune markers between MS and HC. (2) Associations between immune markers (Th17, Tregs) and gut microbiota (Bacteroidetes and Actinobacteria) had been noted. Tremlett et al. [132 ] Children ≤ 18 MS HC IFN-β GA Natalizumab Corticosteroids Untreated Desulfovibrionaceae (Bilophila, Desulfovibrio, Christensenellaceae) Lachnospiraceae Ruminococcaceae (1) Observed children very early in their MS which close to MS onset. (2) Onset of MS with more subtle changes rather than in the community composition. Branton et al. [143 ] PPMS RRMS SPMS HC Actinobacteria in RRMS Proteobacteria in PPMS Actinobacteria in PP-MS (1) Using brain biopsies for MS, and RNA sequence analysis for bacteria. (2) Composition of the bacteria maybe different from gut. Wilson et al. [137 ] MS HC Actinobacteria Bifidobacterium Streptococcus Bacteroides, Faecalibacterium, Prevotella, Anaerostipes Clostridia XIVa and IV Clusters Tremlett et al. [133 ] MS IFN-β GA Natalizumab Untreated Firmicutes Archaea Euryarchaeota Fusobacteria Absence (versus presence) of Fusobacteria was associated with relapse risk Cantarel et al. [138 ] MS HC GA Untreated Vitamin D Ruminococcus Faecalibacterium, Bacteroidaceae Faecalibacterium Faecalibacterium increased for GA naïve MS relative to GA-treated MS and HC. Rumah et al. [139 ] RRMS SPMS HC C. perfringens type A Chen et al. [140 ] MS HC IFN-β GA Natalizumab Untreated Pseudomonas, Mycoplana, Haemophilus, Blautia, Dorea Parabacteroides, Adlercreutzia, Prevotella Rumah et al. [161 ] Fingolimod DMF Teriflunomide C. perfringens Inhibition of C. perfringens growth may contribute to the clinical efficacy of MS