Several cell types have been proposed to create niches for haematopoietic stem cells (HSCs). However, the expression patterns of HSC maintenance factors have not been systematically studied and no such factor has been conditionally deleted from any candidate niche cell. Thus, the cellular sources of these factors are undetermined. Stem cell factor (SCF; also known as KITL) is a key niche component that maintains HSCs. Here, using Scf(gfp) knock-in mice, we found that Scf was primarily expressed by perivascular cells throughout the bone marrow. HSC frequency and function were not affected when Scf was conditionally deleted from haematopoietic cells, osteoblasts, nestin-cre- or nestin-creER-expressing cells. However, HSCs were depleted from bone marrow when Scf was deleted from endothelial cells or leptin receptor (Lepr)-expressing perivascular stromal cells. Most HSCs were lost when Scf was deleted from both endothelial and Lepr-expressing perivascular cells. Thus, HSCs reside in a perivascular niche in which multiple cell types express factors that promote HSC maintenance.
We have not found any resources mentioned in this publication.
SciCrunch is a data sharing and display platform. Anyone can create a custom portal where they can select searchable subsets of hundreds of data sources, brand their web pages and create their community. SciCrunch will push data updates automatically to all portals on a weekly basis. User communities can also add their own data to SciCrunch, however this is not currently a free service.