• The role of gut microbiome in regulating immune response and treating or controlling the autoimmune disease IBD
  • Mahdi Mondali,1,*
    1. Imam Hossein Comprehensive University Student


  • Introduction: The gut microbiome is a vast collection of bacteria, viruses, fungi, and other microorganisms that function as a complex ecosystem in the human digestive tract. Growing scientific evidence indicates that this ecosystem plays a key role in shaping, regulating, and modulating the body's immune responses, and an imbalance in it (Dysbiosis) can be associated with the onset and progression of autoimmune diseases, especially inflammatory bowel diseases (IBD) such as Crohn's and ulcerative colitis. The close connection between changes in the gut microbiome and inflammatory immune responses has opened new horizons in understanding pathophysiology as well as designing microbiome-based targeted therapies.
  • Methods: The methodology of this research is based on a systematic review of authoritative scientific sources, including articles published in PubMed, Nature Reviews Immunology, and Science databases, as well as reference books on immunology and microbiology. In this study, the structure and composition of the gut microbiome are first addressed, followed by an examination of its role in regulating immune responses, and then an analysis of its connection to autoimmune diseases, particularly IBD. In the final section, novel therapeutic approaches based on microbiome modulation (including probiotics, fecal microbiota transplantation, and dietary interventions) are discussed.
  • Results: Findings indicate that certain symbiotic bacteria, such as Faecalibacterium prausnitzii and Bacteroides fragilis, have anti-inflammatory roles and can help modulate the immune system by producing metabolites like short-chain fatty acids (SCFAs) {1}. In contrast, an increase in pathogenic bacteria like adherent-invasive Escherichia coli (AIEC) is associated with exacerbated inflammation and the onset of IBD {2}.
  • Conclusion: The conclusion of this article indicates that the gut microbiome not only plays a vital role in immune regulation but can also serve as a potential therapeutic tool for autoimmune diseases such as IBD. These findings pave the way for the development of personalized, microbiome-based treatments in the future. Multiple molecular and cellular mechanisms are employed by the microbiome in immune regulation. SCFAs, PSA, tryptophan fermentation products, and other metabolites activate key signaling pathways such as HDAC inhibition and AhR activation, balance Treg and Th17 cells, and modulate inflammatory responses. These findings demonstrate that the microbiome is not merely recognized as a symbiotic factor but is an active regulator of the immune system that can shape novel therapeutic pathways.
  • Keywords: Gut microbiome, autoimmune diseases, IBD, probiotics, fecal microbiota transplantation.