Host microbiome-immune system axis

The host microbiome-immune system axis represents the complex, bidirectional communication network between commensal microorganisms and the host's immune apparatus. This interaction is fundamental to the development of the immune system, particularly in the maturation of lymphoid tissues and the calibration of inflammatory thresholds (Belkaid & Hand, 2014, Science). The microbiome produces metabolites such as short-chain fatty acids (SCFAs) that promote the differentiation of regulatory T cells, thereby maintaining systemic immune tolerance and preventing autoimmunity (Round & Mazmanian, 2009, Nature Reviews Immunology). Disruptions in this balance, known as dysbiosis, are implicated in the pathogenesis of numerous conditions, including inflammatory bowel disease, allergies, and metabolic disorders (Thaiss et al., 2016, Nature). In modern pharmacology, the microbiome is increasingly recognized as a modulator of drug efficacy, particularly in oncology, where specific gut bacteria can enhance the response to immune checkpoint inhibitors (Gopalakrishnan et al., 2018, Science). Therapeutic interventions targeting this axis include probiotics, prebiotics, and fecal microbiota transplantation, which aim to restore homeostatic microbial-immune interactions.

Other names

Gut-immune axisMicrobiota-immune system crosstalkHost-microbe interactionsCommensal-immune system interaction

Modulation of the host immune system through microbial metabolites such as short-chain fatty acids (SCFAs), direct cell-to-cell contact between microbes and pattern recognition receptors (PRRs), and competition for ecological niches, which collectively induce regulatory T cell (Treg) differentiation and maintain mucosal barrier integrity (Round & Mazmanian, 2009, Nature Reviews Immunology).