Gut microbiota-intestinal barrier-immune system axis

The gut microbiota-intestinal barrier-immune system axis is a complex, multi-component biological network essential for maintaining systemic homeostasis and immune tolerance (Thursby & Juge, 2017, Biochemical Journal). This axis involves a continuous dialogue between trillions of commensal microorganisms, the physical intestinal epithelium, and the gut-associated lymphoid tissue (GALT), which contains the majority of the body's immune cells (Belkaid & Hand, 2014, Cell). The microbiota produces metabolites such as short-chain fatty acids (SCFAs) that strengthen the intestinal barrier by promoting tight junction integrity and signaling to immune cells to maintain a non-inflammatory state (Vancamelbeke & Vermeire, 2017, Therapeutic Advances in Gastroenterology). A functional intestinal barrier, regulated by proteins like zonulin and occludin, prevents the translocation of harmful pathogens and endotoxins into the bloodstream. Dysregulation of this system, often termed dysbiosis, is linked to increased intestinal permeability ("leaky gut") and is a key driver in the pathogenesis of inflammatory bowel disease (IBD), metabolic syndrome, and various autoimmune conditions (Fan & Pedersen, 2021, Nature Reviews Microbiology). Therapeutic interventions targeting this axis, such as probiotics, prebiotics, and fecal microbiota transplantation, aim to restore microbial balance and reinforce the host's mucosal defenses (Cunningham et al., 2021, Nature Reviews Gastroenterology & Hepatology).

Other names

Gut-immune axisMicrobiome-gut-immune axisIntestinal mucosal barrier systemGut-microbiota-immune interface

Modulation of microbial diversity, restoration of intestinal tight junction integrity, induction of mucosal tolerance, and suppression of systemic endotoxemia.