Pathogen antagonism in gastrointestinal tract

Pathogen antagonism in the gastrointestinal tract is a collective term describing how commensal (beneficial) gut microbiota defend the host against pathogenic microorganism colonization and overgrowth. This phenomenon—also known as colonization resistance—involves a range of mechanisms such as nutrient competition, direct antimicrobial production, competitive exclusion, stimulation of host immune response, and maintenance of barrier integrity. These effects protect against infectious diseases, maintain immune homeostasis, and prevent dysbiosis-related disorders. Loss or disruption of this antagonistic balance (e.g., after antibiotic treatment) can predispose to pathogen colonization, infection, and inflammatory diseases[1][2][3][4].

Other names

Colonization resistanceGut microbiota-mediated pathogen antagonismMicrobial antagonism in GI tract

Competition for nutrients; Production of bacteriocins and antimicrobial peptides; Stimulation of host immune factors (e.g., IgA, cytokines); Niche exclusion.