Hematopoietic stem and progenitor cells: their mobilization and homing to bone marrow and peripheral tissue.

Hematopoietic stem and progenitor cells (HSPCs) are a rare population of precursor cells that possess the capacity for self-renewal and multilineage differentiation. In the bone marrow (BM), HSPCs warrant blood cell homeostasis. In addition, they may also replenish tissue-resident myeloid cells and directly participate in innate immune responses once they home to peripheral tissues. In this review, we summarize recent data on the signaling molecules that modulate the mobilization of HSPCs from BM and their migration to peripheral tissues.