Cellular Interactions in the Stem Cell Niche

摘要

The ability of stem cells to both self-renew and differentiate into many different cell types enables these versatile cells to generate and repair tissues and organs. Yet studies of the fruit fly Drosophila and of mammalian skin, intestine, bone marrow, and brain reveal that these inherent stem cell features are tightly regulated by the cells and proteins that constitute the extracellular environment (or "niche") that stem cells inhabit (1). On page 1338 of this issue, Shen et al. (2) take an important step forward in our understanding of the stem cell niche. They show that en-dothelial cells (ECs) that are enriched in the niche occupied by neural stem cells (NSCs) regulate NSC proliferation and induce these stem cells to become neurons in vitro.