Macrophages - intestine / brain
Macrophages are strategically positioned throughout the organism. As professional phagocytes, they ingest and degrade debris and foreign material, including pathogens, and orchestrate inflammatory processes. Macrophages can be generated from distinct sources: two early, currently considered transient, hematogenic waves initiated in the yolk sac that seeds tissue macrophages prenatally, and a pathway involving hematopoietic stem cells and monocytes, that persists throughout adult life. Most macrophage compartments are established prenatally, and develop independently from each other in their respective host tissue under the influence of the local microenvironment. Recent studies revealed critical contributions of tissue macrophages to organ development and homeostasis. Specific involvement of macrophages in the maintenance of the healthy balanced steady-state remains for most tissues however incompletely defined. Using the mouse as a model, we aim to define functional contributions of specific tissue macrophages to physiology and pathophysiology.