Ingo Roeder

Keywords hematopoietic stem cells hepatoblasts 3D quantitative imaging niches Introduction Fetal liver (FL) tissues play fundamental roles in the development of the hematopoietic system.1 In mice, the FL primordium is seeded by a heterogeneous set of hematopoietic progenitors (HPCs) with limited differentiation potential, which are generated in the yolk sac (FS) between days 7 and 9 of gestation (E7 and E9) and support hematopoietic function throughout fetal life.2,3 Shortly after (E11.5),...

Adult stem cells persist lifelong in the organism, where they are responsible for tissue homeostasis and repair. It is commonly assumed that their maintenance and function are facilitated in local environments called "stem cell niches." Although there is convincing evidence that a variety of niche components determine stem cell fate, the regulatory details of stem cell-niche interactions are widely unknown.

Asymmetric cell division is a common concept to explain the capability of stem cells to simultaneously produce a continuous output of differentiated cells and to maintain their own population of undifferentiated cells. Whereas for some stem cell systems, an asymmetry in the division process has explicitly been demonstrated, no evidence for such a functional asymmetry has been shown for hematopoietic stem cells (HSC) so far.