The self renewal of hematopoietic stem cells is regulated by the bone marrow microenvironment. Whereas previous studies have focused on the role of osteoblasts, Ingrid Winkler et al. now show that bone marrow endothelial cells in the so-called 'vascular niche' contribute to this regulation by directly inducing HSC proliferation. In mice, deficiency or antagonism of the endothelial-specific adhesion protein E-selectin promotes HSC quiescence and self renewal. These findings may point to a new treatment strategy for preserving HSC function in patients undergoing chemotherapy.
- Ingrid G Winkler
- Valérie Barbier
- Jean-Pierre Lévesque