Abstract

Stem cells in both embryonic and adult tissues are defined by their unique ability to balance self-renewal and differentiation such that mature cells necessary for tissue function can be generated and replaced without depletion of the stem cell pool. In this issue of Cell, report a major step forward for studying the mechanisms and regulation of such stem cell fate decisions in the blood-forming (hematopoietic) system by providing a simple and broadly applicable method to isolate these cells and to visualize them in their normal environment.