Beyond the gut: decoding the gut-immune-brain axis in health and disease.

Emerging research underscores the pivotal role of the gut-immune-brain axis, a dynamic bidirectional communication system involving intricate interactions between the gut microbiota, immune responses, and the central nervous system. Gut microbes and their metabolites have profound effects on immune and neurological homeostasis, influencing the development and function of multiple physiological systems. Disruption of the composition of the gut microbiota and barrier integrity has been implicated in various neurological and psychiatric disorders, including autism spectrum disorder, Alzheimer's disease, Parkinson's disease, depression, and anxiety.

Gut microbiota and brain-resident CD4 T cells shape behavioral outcomes in autism spectrum disorder.

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by alterations in social, repetitive, and anxiety-like behaviors. While emerging evidence suggest a gut-brain etiology in ASD, the underlying mechanisms remain unclear. To dissect this axis, we developed a germ-free BTBR mouse model for ASD.

Microbial Components and Effector Molecules in T Helper Cell Differentiation and Function.

The mammalian intestines harbor trillions of commensal microorganisms composed of thousands of species that are collectively called gut microbiota. Among the microbiota, bacteria are the predominant microorganism, with viruses, protozoa, and fungi (mycobiota) making up a relatively smaller population. The microbial communities play fundamental roles in the maturation and orchestration of the immune landscape in health and disease.

The gut-immune-brain axis in neurodevelopment and neurological disorders.

The gut-brain axis is gaining momentum as an interdisciplinary field addressing how intestinal microbes influence the central nervous system (CNS). Studies using powerful tools, including germ-free, antibiotic-fed, and fecal microbiota transplanted mice, demonstrate how gut microbiota perturbations alter the fate of neurodevelopment. Probiotics are also becoming more recognized as potentially effective therapeutic agents in alleviating symptoms of neurological disorders.

Of men in mice: the development and application of a humanized gnotobiotic mouse model for microbiome therapeutics.

Considerable evidence points to the critical role of the gut microbiota in physiology and disease. The administration of live microbes as a therapeutic modality is increasingly being considered. However, key questions such as how to identify candidate microorganisms and which preclinical models are relevant to recapitulate human microbiota remain largely unanswered.