Hematopoietic stem cell trafficking

Hematopoiesis is sustained by a renewable pool of stem cells that interacts with distinct, sequential and specific microenvironments during normal development and throughout adult life. Hematopoietic stem cells (HSCs) are unique in their ability to migrate to various sites, ensuring the safety and integrity of their regenerative potential. This review is focused on the guidance cues and molecular pathways regulating HSC trafficking throughout the lifetime of the organism. We examine and discuss recent findings that shed new light into the molecular connections that feed a complex network between stem cells and their microenvironment, implicating parallel mechanisms for non-hematopoietic stem cells. Hematopoietic stem cell (HSC) migration throughout life is believed to be central to hematopoiesis under homeostasis. Blood circulation enables regulated trafficking of HSCs from specific embryonic and extra-embryonic sites to the fetal liver, ending their developmental journey in the bone marrow (BM) where most of the definitive *Edited by David Scadden. Last revised April 29, 2008. Published July 14, 2008. This chapter should be cited as: Magnon, C. and Frenette, P.S., Hematopoietic stem cell trafficking (July 14, 2008), StemBook, ed. The Stem Cell Research Community, StemBook, doi/10.3824/stembook.1.8.1, http://www.stembook.org. Copyright: C © 2008 Claire Magnon and Paul S. Frenette. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. §Correspondence and requests for materials should be addressed to P.S.F. (e-mail: [email protected]).