Single cell analysis of emergent haematopoiesis in the human fetal bone marrow (SS2)

Haematopoeisis emerges in the human fetal bone marrow (BM) at around 12 post conception weeks. This constitutes the second wave of definitive haematopoiesis following on from the first wave in fetal liver from around 6 post conception weeks. The BM emerges as the dominant site of haematopoiesis, responsible for lifelong blood and immune cell production. Yet, little is known about how the composition of the fetal BM, the microenvironment permissive to establishing haematopoiesis and the interplay with other sites of fetal haematopoiesis in fetal health or disease. Herein we utilise single cell RNA sequencing to describe fetal haematopoeisis throughout gestation and better understand the development of the human immune system.