Neuroimmune Mechanisms in Gastrointestinal Disorders: Integrating Gut–Brain Axis Signaling into Clinical and Diagnostic Frameworks
DOI:
https://doi.org/10.64784/128Keywords:
Neuroimmune interactions, gut–brain axis, gastrointestinal diseases, inflammatory bowel disease, irritable bowel syndrome, microbiota, visceral hypersensitivity, vagus nerve, neurogastroenterology, immune modulationAbstract
Neuroimmune interactions have emerged as a central framework for understanding the complexity of gastrointestinal diseases, integrating immune regulation, neural signaling, and microbiota-driven mechanisms within the gut–brain axis. This review synthesizes current evidence on the role of neuroimmune pathways in both inflammatory and functional gastrointestinal disorders, with particular emphasis on inflammatory bowel disease and irritable bowel syndrome. The analyzed literature demonstrates that gastrointestinal symptom generation and disease expression result from dynamic interactions among immune cells, enteric and autonomic neural circuits, microbial signaling, and stress-related modulation rather than from isolated pathological processes. In inflammatory conditions, immune dysregulation and macrophage-mediated pathways predominate, while neural and autonomic mechanisms contribute to symptom persistence and variability. In functional disorders, immune–neural coupling, mast cell–nerve interactions, and visceral sensory sensitization emerge as key drivers of pain and altered bowel habits despite minimal structural abnormalities. Across both disease categories, the intestinal microbiota acts as a cross-cutting regulator influencing immune tone, barrier integrity, and neural responsiveness. From a clinical and diagnostic perspective, these findings support a mechanism-based approach that complements traditional inflammatory and structural assessments with neuroimmune-informed reasoning. This integrative framework has particular relevance for medical education and clinical practice in diverse healthcare settings, including Latin America, where resource variability necessitates strong pathophysiological interpretation. Overall, neuroimmune models provide a coherent and biologically grounded perspective for advancing diagnosis, teaching, and future translational strategies in gastroenterology.
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