First published online October 12, 2006
Development 133, 2101e (2006)
© The Company of Biologists Limited
Haematopoiesis and placental potential
During mouse embryonic development, haematopoietic cells develop at several
sites in the embryo, such as the yolk sac. The mid-term placenta also contains
many haematopoietic cells but, until now, it has been unclear whether it is a
source of haematopoietic cells or a stem cell niche. On
p. 4183, Zeigler and
co-workers help resolve this issue by demonstrating that the placenta has
haematopoietic potential. The chorio-allantoic placenta of mammals forms
through the fusion of the allantois (the precursor of the umbilical cord) and
the chorion, which forms the chorionic disc. By isolating the allantois and
chorion from mouse embryos before the establishment of the embryonic
circulation, the researchers show that both tissues contain cells that express
Runx1, a transcription factor that is required for haematopoietic stem cell
formation. Furthermore, both tissues form myeloid and erythroid cells in
explant cultures, even before chorio-allantoic fusion. The researchers
conclude that both of the tissues that form the mammalian placenta, like the
allantois in avian embryos, have intrinsic haematopoietic properties.
Related articles in Development:
- The allantois and chorion, when isolated before circulation or chorio-allantoic fusion, have hematopoietic potential
- Brandon M. Zeigler, Daisuke Sugiyama, Michael Chen, Yalin Guo, Karen M. Downs, and Nancy A. Speck
Development 2006 133: 4183-4192.
[Abstract]
[Full Text]