Publication Type	Academic Article
Authors	Heissig B, Hattori K, Dias S, Friedrich M, Ferris B, Hackett N, Crystal R, Besmer P, Lyden D, Moore M, Werb Z, Rafii S
Journal	Cell
Volume	109
Issue	5
Pagination	625-37
Date Published	05/31/2002
ISSN	0092-8674
Keywords	Bone Marrow, Cell Differentiation, Cell Movement, Hematopoietic Stem Cells, Matrix Metalloproteinase 9, Stem Cell Factor
Abstract	Stem cells within the bone marrow (BM) exist in a quiescent state or are instructed to differentiate and mobilize to circulation following specific signals. Matrix metalloproteinase-9 (MMP-9), induced in BM cells, releases soluble Kit-ligand (sKitL), permitting the transfer of endothelial and hematopoietic stem cells (HSCs) from the quiescent to proliferative niche. BM ablation induces SDF-1, which upregulates MMP-9 expression, and causes shedding of sKitL and recruitment of c-Kit+ stem/progenitors. In MMP-9-/- mice, release of sKitL and HSC motility are impaired, resulting in failure of hematopoietic recovery and increased mortality, while exogenous sKitL restores hematopoiesis and survival after BM ablation. Release of sKitL by MMP-9 enables BM repopulating cells to translocate to a permissive vascular niche favoring differentiation and reconstitution of the stem/progenitor cell pool.
DOI	10.1016/s0092-8674(02)00754-7
PubMed ID	12062105
PubMed Central ID	PMC2826110