Microbial regulation of human colon immune homeostasis

The article presents a fresh look at the role of the intestinal microbiota in symbiosis with the human body. The study of the “microbe–host” system in the framework of infectious symbiology allowed us to establish that intestinal bacteria regulate and maintain the immune homeostasis of the large intestine with the help of their metabolites. Thus, it became possible to control the immune homeostasis of the large intestine through exposure to associations of microsymbionts capable of altering the cytokine status and response of innate immunity. Multicomponent associations of microsymbionts of the large intestine have been established, which under conditions of eubiosis maintain a balanced profile of pro- and anti-inflammatory cytokines. In dysbiosis, an increased number of associations of opportunistic pathogens leads to a shift in the balance towards pro-inflammatory cytokines and an increase in the level of antimicrobial proteins in the intestine. The multidirectional effects on cytokine production of extracellular metabolites of microsymbionts isolated during eubiosis and dysbiosis can serve as the basis for the selection of strains with anti-inflammatory activity.