Gut Motility

Macrophages help food move through

See allHide authors and affiliations

Science  18 Jul 2014:
Vol. 345, Issue 6194, pp. 281
DOI: 10.1126/science.345.6194.281-g
Muscularis macrophages (green) on nerve fibers (red)PHOTO: MILENA BOGUNOVIC

Food needs a complex array of cellular interactions to move through the body. Neurons, muscle cells, and interstitial cells all cooperate to ease it through the gastrointestinal (GI) tract. Now Muller et al. report intestinal muscularis macrophages, a type of immune cell that resides in the smooth muscles that surround the GI tract, participate, too. These macrophages secrete a substance called bone morphogenetic protein 2 (BMP2), which binds to enteric neurons and directs them to coordinate the muscle cell contractions that squeeze food through. The neurons, in turn, produce a growth factor required by the macrophages. Macrophage-neuron crosstalk is essential: When mice don't have enough of the growth factor, BMP2, or muscularis macrophages, they have defects in gut muscle contractions.

Cell 10.1016/j.cell.2014.04.050 (2014).

Navigate This Article