The role of intestinal macrophages and the enteric nervous system in gut neuroimmunology. Basic science and clinical...

A properly functioning gastrointestinal tract is essential for nutrient transport, absorption, digestion, and removal of metabolic waste, but protection from pathogens, allergens and toxins also belongs to its tasks, just as the constant homeostatic control and regulation of its internal microenvironment. The largest part of these functions is carried out by the continuously interacting enteric nervous and immune system, constantly adapting to internal and external stress. The intestines serve as a habitat for the microorganisms situated in their lumen, meanwhile the microbiota strongly influence the development, motility and immunological function of the gut. The gastrointestinal tract and its microbiota regulate digestion, immune, neuroendocrine and neural functions of the gut. These closely associated and cooperating structures are called together the microbiome-gut-brain axis. The basis of this interaction is considered to be the neuroimmunological crosstalk between the enteric nervous system and intestinal macrophages. In this review, we would like to summarize the most important and latest findings of this emerging field, including the possible clinical implications of pathological conditions caused by the elimination or radical change of commensal microbiota. Orv Hetil. 2020; 161(19): 771-779.