Gut microbial ecosystem and host immune system

The **gut microbial ecosystem and host immune system** constitute a dynamic, interdependent network where trillions of microbes interact with the host’s innate and adaptive immune components through direct cell contact and vast arrays of metabolites. This crosstalk is fundamental to health, affecting nutrient absorption, epithelial barrier function, immune development, and protection against pathogens. Disruptions in these interactions (“dysbiosis”) can result in inflammation, autoimmunity, metabolic disturbances, infection, and even influence cancer progression and therapeutic outcomes. The ecosystem is so complex that targeting the entire system pharmacologically is not practical; instead, research is focused on modifying specific microbiota members, their metabolites, or host immune pathways.

Other names

Gut microbiota and immune systemMicrobiome-immune axisIntestinal microbiome and host immunityMicrobiota-gut-immune crosstalkGut-brain-immune axis (when brain interactions considered)

Modulation of microbial composition and metabolite production (probiotics, FMT, antibiotics); Regulation of host immune cell (T cell, B cell, dendritic cell) differentiation via microbial metabolites (SCFAs, ATP, polysaccharides); Restoration of epithelial barrier integrity; Enhancement or suppression of inflammatory responses