TY - JOUR AU - Gustafsson, Karin AU - Welsh, Michael PY - 2016 TI - Maintenance of hematopoietic stem cell dormancy: yet another role for the macrophage JF - Stem Cell Investigation; Vol 3, No 9 (September 2016): Stem Cell Investigation Y2 - 2016 KW - N2 - Hematopoietic stem cells (HSC) possess several unique features that ensure a life-long supply of all bone marrow derived blood cell lineages (1). In adulthood, they are mainly localized to the bone marrow and depend on a supportive niche for maintaining their long-term (LT) repopulating ability while simultaneously having a capacity for multi-potent differentiation. The HSC niche has been suggested to be composed of vascular endothelial cells, perivascular mesenchymal stromal cells (2-4), osteoblasts (5) as well as mature hematopoietic cells like megakaryocytes and macrophages (6-9). Furthermore, HSC maintain a low cell cycle activity to prevent exhaustion of their replicative capacity (10). In addition, recent findings suggest that HSC can be subdivided into LT or short-term (ST) HSC of which the latter have a greater propensity for lineage-specific differentiation (11). Mouse LT-HSCs are enriched in a cell population immunophenotypically characterized as Lin − (lineage negative), c-Kit + , Sca1 + , CD150 + , CD34 − , Flk2/Flt3 − and CD48 − cells. A recent study adds expression of Hoxb5 to these markers for providing additional definition of the LT-HSC population (12). UR - https://sci.amegroups.org/article/view/11696