Date of Defense
12-2-2025
Date of Graduation
5-2026
Department
Nursing
First Advisor
Natalie Kuhn
Second Advisor
Wendy Kershner
Third Advisor
Elissa Allen
Keywords
Multiple sclerosis, gut microbiome, dysbiosis, gut-brain axis, blood-brain barrier, autoimmunity, fecal microbiota transplantation, probiotics
Abstract
This literature review explores the multifaceted relationship between gut microbiome (GM) dysbiosis and multiple sclerosis (MS), highlighting key themes that advance understanding of disease pathogenesis and therapeutic potential for treatments targeting the gut. The review underscores the immune system dysregulation in MS, emphasizing the roles of T cells, B cells, and microglia in neuroinflammation and demyelination. Historically, MS pathogenesis was thought to be driven mainly by T-cell dysregulation, but current research highlights the additional roles of B-cells and microglia, the resident immune cells of the central nervous system (CNS). Additionally, this literature review identifies GM alterations and dysbiosis as critical factors influencing MS progression through the gut-brain axis, where microbial imbalances affect immune responses and blood-brain barrier (BBB) integrity. The GM, composed of the microorganisms and metabolic environment within the gastrointestinal (GI) tract, communicates with the CNS through immune, metabolic, and neural pathways collectively known as the gut-brain axis. The review also discusses mechanistic insights linking GM dysbiosis to autoimmunity, including molecular mimicry, impaired BBB function, and the regulatory role of microbial metabolites such as short-chain fatty acids. The literature indicated that MS patients exhibit distinct microbial profiles, including reduced levels of beneficial species such as Prevotella, Faecalibacterium, Roseburia, and Bacteriodes, and increased abundance of potentially pro-inflammatory taxa such as Akkermansia and Streptococcus. Finally, emerging therapeutic interventions targeting the GM, including fecal microbiota transplantation (FMT) and probiotics, are presented as promising strategies for modulating immune activity and improving clinical outcomes in MS patients. Both of these therapies have shown reduced clinical symptom severity and improved regulatory T-cell activity function in both animal models and preliminary human trials. These themes collectively highlight the potential of GM-focused approaches in understanding and managing MS. A comprehensive literature search was conducted using CINAHL, PubMed, and Scopus, yielding several hundred peer-reviewed articles focused on microbiome composition, immune modulation, and MS pathophysiology, however, not all these articles were relevant or reviewed for this study. There were 18 articles reviewed, due to their relevance specifically to the relationship between the gut microbiome and the autoimmune response in MS, or if they explored gut-based therapeutic interventions in autoimmune diseases. Studies were excluded if they were not peer-reviewed, not available in English, or focused on autoimmune conditions unrelated to MS.
Recommended Citation
Houtrouw, Abigail, "Investigating the Mechanisms by Which Gut Microbiome Dysbiosis Contributes to the Autoimmune Response in Multiple Sclerosis" (2025). Honors Theses. 4032.
https://scholarworks.wmich.edu/honors_theses/4032
Access Setting
Honors Thesis-Open Access
Presentation