The role of the yolk sac in human fetal development and identification of a hepatocyte-like cell in the human yolk sac (SS2)
The human yolk sac (YS) is an extra-embryonic tissue critical for early prenatal life development. It is the first site of haematopoiesis where progenitors differentiate from endoderm within blood islands of the yolk sac contributing initially to primitive erythropoiesis and in subsequent waves to erythro-myeloid and lymphoid differentiation.