FUNCTIONAL MICROBIAL PATHWAYS LINKING GUT DYSBIOSIS TO IMMUNE ACTIVATION IN INFLAMMATORY BOWEL DISEASE: A REVIEW

Abstract

Inflammatory bowel disease (IBD) is a chronic inflammatory condition marked by persistent immune activation and disruption of intestinal homeostasis. Although gut dysbiosis is a consistent feature of IBD, the specific microbial species involved vary widely across patients and cohorts. In contrast, microbial functional pathways show greater consistency and represent the components of the microbiome most directly sensed by the host immune system. This review integrates findings from published experimental, clinical, and multi-omics studies investigating microbial functional pathways and immune activation in IBD. Accumulating evidence indicates that IBD is associated with increased pro-inflammatory microbial functions alongside a reduction in regulatory metabolites, particularly short-chain fatty acids (SCFAs) such as butyrate. This review emphasizes that concentrating on microbial functional pathways elucidates how diverse microbial communities can induce analogous inflammatory responses in IBD. Understanding these conserved microbial functions may help explain the biological basis of persistent inflammation in IBD.