[The intestinal microbiota in inflammatory bowel diseases]

Area of Science:

• Gastroenterology
• Microbiology
• Immunology

Context:

• The intestinal microbiota plays a critical role in gastrointestinal health and is implicated in inflammatory bowel diseases (IBD).
• Despite extensive research, the precise mechanisms linking gut dysbiosis to IBD pathogenesis are not fully understood.
• Existing knowledge highlights the complex interplay between microbial communities and the host immune system in IBD.

Purpose:

• To review the current understanding of alterations in the gut microbiota in IBD patients.
• To discuss the causal relationship between microbiota changes and IBD pathogenesis.
• To explore current and future diagnostic and therapeutic strategies targeting the gut microbiota for IBD.

Summary:

• IBD patients exhibit altered gut microbiota composition, diversity, and function, though no universal IBD-specific bacteria have been identified.
• A healthy microbiota possesses anti-inflammatory properties, while the IBD microbiota can promote inflammation by compromising the intestinal barrier and interacting with the immune system.
• The balance between pro-inflammatory and anti-inflammatory microbial activities is crucial in IBD development.

Impact:

• Microbiota-based diagnostics for IBD show potential but require further validation for clinical application.
• Therapies such as probiotics and fecal microbiota transplantation have demonstrated clinical benefits, particularly in ulcerative colitis.
• A deeper mechanistic understanding of microbiota-host interactions is essential for advancing microbiota-based diagnostics and therapies for IBD.