Macrophages Keep Your Gut Moving

Schematic diagram of the interaction between the intestinal muscularis externa (MMo) macrophages and the enteric nervous system (ENS) neurons during different developmental periods. At the early postnatal stage, MMos play a critical role in ENS maturation and refinement through synaptic pruning and enteric neuron phagocytosis. In addition, during the adult stage, a specific MMo subset named neuron-associated (NA)-MMo, supports enteric neuronal survival and functions. Conversely, enteric neurons promote the phenotypic MMo changes by secreting transforming growth factor -3 (TGF3), transitioning them from a phagocytic phenotype in the early postnatal period to a neuroprotective and immune-surveillant phenotype in the young adult period. Disruptions in these interactions could lead to alterations in the enteric neuron numbers, ultimately resulting in reduced gut motility.