Physiological Migration of Hematopoietic Stem and Progenitor Cells

• DOI: 10.1126/science.1064081
• Publication Date: 2002-07-27T09:47:15Z
• Authors: Douglas E. Wright; Amy J. Wagers; Anjali Pathak Gulati; Frances L. Johnson; Irving L. Weissman
• Keywords: 0301 basic medicine; 0303 health sciences; Time Factors; Chimera; Hematopoietic Stem Cell Transplantation; Hematopoietic Stem Cells; Hematopoiesis; Mice; 03 medical and health sciences; Cell Movement; Blood Circulation; Animals; Homeostasis; Leukocyte Common Antigens

Hematopoietic stem cells (HSCs) reside predominantly in bone marrow, but low numbers of HSCs are also found in peripheral blood. We examined the fate of blood-borne HSCs using genetically marked parabiotic mice, which are surgically conjoined and share a common circulation. Parabionts rapidly established stable, functional cross engraftment of partner-derived HSCs and maintained partner-derived hematopoiesis after surgical separation. Determination of the residence time of injected blood-borne progenitor cells suggests that circulating HSCs/progenitors are cleared quickly from the blood. These data demonstrate that HSCs rapidly and constitutively migrate through the blood and play a physiological role in, at least, the functional reengraftment of unconditioned bone marrow.