Gut microbial ecosystem and host gut-immune axis (Gut-immune axis)

The gut microbial ecosystem and host gut-immune axis is a complex, bidirectional communication network between the trillions of microorganisms in the gastrointestinal tract and the host's immune system [1]. This axis is critical for the development of the gut-associated lymphoid tissue (GALT) and the maintenance of systemic immune homeostasis [2]. The microbiota influences immune cell differentiation, such as the induction of regulatory T cells (Tregs) via the production of short-chain fatty acids (SCFAs) like butyrate [3]. Dysbiosis, or the imbalance of this ecosystem, is strongly associated with inflammatory bowel disease (IBD), allergies, and metabolic syndromes [4]. Furthermore, the composition of the gut microbiome has been shown to modulate the efficacy of immune checkpoint inhibitors in cancer treatment [5]. Therapeutic interventions targeting this axis include probiotics, prebiotics, and fecal microbiota transplantation (FMT), which aim to restore a healthy microbial-immune balance [6]. While not a single molecular target, this system is a major focus of modern drug development and personalized medicine. (Sources: [1] Belkaid Y, et al. Cell 2014; [2] Round JL, et al. Nat Rev Immunol 2009; [3] Furusawa Y, et al. Nature 2013; [4] Lynch SV, et al. N Engl J Med 2016; [5] Gopalakrishnan V, et al. Science 2018; [6] Khoruts A, et al. Nat Rev Gastroenterol Hepatol 2016).

Other names

Gut-microbiota-immune axisMicrobiome-immune axisIntestinal immune system-microbiota interfaceGut-associated lymphoid tissue (GALT) ecosystem

Modulation of microbial diversity and metabolite production (e.g., short-chain fatty acids) to regulate host immune cell signaling, particularly through the induction of regulatory T cells and activation of pattern recognition receptors.