Skip to main content
. Author manuscript; available in PMC: 2009 Jan 16.
Published in final edited form as: Cell. 2008 Feb 22;132(4):631–644. doi: 10.1016/j.cell.2008.01.025

Figure 3. Stem Cell Niche in the Adult Bone Marrow.

Figure 3

HSCs are found adjacent to osteoblasts that are under the regulation of bone morphogenetic protein (BMP) (the osteobast niche). HSCs are also found adjacent to blood vessels (the vascular niche). The chemokine CXCL12 regulates the migration of HSCs from the circulation to the bone marrow. The osteoblast and vascular niches in vivo lie in close proximity or may be interdigitated. The marrow space also contains stromal cells that support hematopoiesis including the production of cytokines, such as c-Kit ligand, that stimulate stem cells and progenitors. Cytokines, including interleukins, thrombopoietin (Tpo), and erythropoietin (Epo), also influence progenitor function and survival.