Topic: Immunomodulation of Gut–Brain Interactions in Health and Disease

The gut–brain axis is increasingly recognized as a complex and dynamic bidirectional communication network through which the intestinal microbiome profoundly influences host physiology and brain function. Within this network, the gut microbiome acts not merely as a passive correlate of neurological and neuropsychiatric outcomes, but as an active metabolic and ecological hub that produces a diverse repertoire of bioactive molecules. Through these microbial signals, the gut microbiome contributes to the maintenance of intestinal and brain homeostasis while serving as a key molecular mediator of communication across the microbiome–gut–brain axis. In this context, the gut microbiome functions as a dynamic metabolic interface that integrates environmental, dietary, and host-derived signals, thereby shaping central nervous system function across diverse physiological and pathological conditions.

This Special Issue aims to bring together cutting-edge research investigating the molecular and cellular mechanisms through which the gut microbiome modulates immune processes within the gut–brain axis. Particular emphasis will be placed on the complex interactions among microbial communities, microbiome-derived metabolites, immune cells, neural pathways, and central nervous system function. By integrating perspectives from microbiology, immunology, neuroscience, metabolomics, and systems biology, this Special Issue seeks to advance mechanistic understanding of microbiome-mediated immunomodulation and its role in shaping gut–brain interactions in both health and disease.

Topics of interest include, but are not limited to:

● Microbiome-mediated regulation of neuroimmune signaling;

● Gut microbiome control of microglial function and neuroinflammation;

● Microbial metabolites and immunomodulation along the gut–brain axis;

● Microbiome–blood–brain barrier interactions;

● Gut microbiome, peripheral immunity, and central nervous system function;

● Microbiota-driven vagal and neuroendocrine pathways;

● Microbiome–immune interactions in neurological and neuropsychiatric disorders;

● Multi-omics and systems biology approaches to gut–brain mechanisms.

Gut–brain axis, microbiome, microbial metabolites, immunomodulation, neuroimmune signaling, blood–brain barrier, microglia, synaptic plasticity, microbial ecology, multi-omics