THE INFLUENCE OF GUT MICROBIOTA ON THE HUMAN IMMUNE SYSTEM
Keywords:
gut microbiota, microbiome, immune system, dysbiosis, gut-immune axis, short-chain fatty acids, regulatory T cells, fecal microbiota transplantation, inflammatory bowel disease, probiotics.Abstract
The human gut microbiota — comprising approximately 38 trillion microorganisms — exerts profound influence on host immune system development, education, and homeostasis. This review synthesizes current mechanistic and clinical evidence regarding the gut-immune axis, focusing on short-chain fatty acid (SCFA)-mediated regulatory T cell induction, pattern recognition receptor (PRR) signaling, and the role of microbial dysbiosis in immune-mediated diseases including inflammatory bowel disease (IBD), allergic disorders, and autoimmune conditions. Data from germ-free animal models, human cohort studies, and intervention trials demonstrate that targeted microbiome modulation — through probiotics, prebiotics, dietary interventions, and fecal microbiota transplantation (FMT) — offers significant therapeutic potential. Future directions include precision microbiome medicine integrating multiomics and artificial intelligence to individualize immune-targeted therapies.
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