BioProject

Hemopoietic stem cells (HSC) reside in marrow niches, producing circulating blood cells. More...

Hemopoietic stem cells (HSC) reside in marrow niches, producing circulating blood cells. Interfacing blood and the niche are sinusoidal endothelial cell lined vessels. Bone marrow (BM) sinusoids have been identified as critical stem cell regulators and a key niche component. However, little is known about the characteristics or functional capacity of marrow endothelial cells. We have identified, prospectively isolated and characterized marrow scavenging sinusoidal endothelial cells with immense endocytic capacity, demonstrating a hierarchical organization and a sub-population highly enriched for endothelial sinusoidal stem cells (BM-ESSC) in endosteal BM with long-term serial transplant potential and revascularization of recipient marrow. In addition, we also demonstrate that BM-ESSC have hemogenic potential: giving rise to long-term multi-lineage reconstituting HSC. These findings represent a paradigm shift and a major advance in the understanding of marrow sinusoidal endothelial cells and HSC in vivo. Identification of human endothelial counterparts and their use in transplantation may lead to improved clinical outcomes. Overall design: Total RNA obtained from cells isolated from mouse bone marrow endosteal region by flow cytometry Less...