Moreover, the yolk sac also plays a role in overall developmental processes such as protein synthesis, gastrointestinal tract formation, stem cell production, and hematopoiesis.

In the mammal, primitive hematopoiesis is first derived from mesodermal cells within a region out of the embryonic sculture known as the yolk sac. Within this region, primitive red cells and ...

*12 Definitive hematopoiesis: During the fetal period, hematopoiesis begins in the yolk sac with primary hematopoiesis and then secondary hematopoiesis occurs in the AGM region.

Certain brain regions of healthy old mice and humans harbor monocyte-derived microglia. The transcriptome of some monocyte-derived microglia was identical to that of yolk sac-derived microglia.

Unlike other embryo models, the structures also contained functional blood islands, or sites on the yolk sac where hematopoiesis takes place.

The yolk sac of the embryo produces two partially overlapping waves of hematopoiesis. The first (primitive) wave gives rise to hematopoietic cells that last only during embryonic development.

Location Primitive erythroid cells can be found in the yolk sac between weeks 2 and 8 of gestation.

A new wave of blood cell production The yolk sac of the embryo produces two partially overlapping waves of hematopoiesis. The first (primitive) wave gives rise to hematopoietic cells that last only ...

At this stage in development, the yolk sac, which nourishes the embryo until the placenta is fully developed, controls hematopoiesis.