Abstract / Description
The human microbiome profoundly influences pathogen virulence and disease susceptibility through diverse molecular mechanisms. This review, focused on literature from 2016 to 2026, synthesizes knowledge on microbiome-mediated regulation examining major pathogens including Vibrio cholerae, enterohemorrhagic Escherichia coli, Salmonella species, Clostridioides difficile, and Staphylococcus aureus. A triangular interaction model is presented, linking host immunity, resident microbiome, and invading pathogen to frame infection outcomes. Commensal bacteria regulate pathogen behavior through quorum sensing interference, metabolite-mediated regulation via short-chain fatty acids and bile acids, competitive exclusion, immune response modulation, and direct antimicrobial production. Key species-Lactobacillus spp. Bifidobacterium spp. Bacteroides thetaiotaomicron, and Faecalibacterium prausnitzii-employ distinct molecular strategies against these pathogens. Organ-on-chip platforms and multi-omics advances reveal context-dependent interactions. Clinical applications including rationally designed probiotics, fecal microbiota transplantation, and precision microbiome engineering show promise despite challenges of inter-individual microbiome variability, representing a paradigm shift toward ecosystem-based infectious disease management.