The quest for hematopoietic stem cells in the embryo. An interview with Françoise Dieterlen-Lièvre. Interview by Thierry Jaffredo and Charles Durand.

Françoise Dieterlen-Lièvre is probably the scientist who has most contributed to our basic knowledge of developmental hematopoiesis. She has dedicated her career to answering cutting edge questions on the origin of hematopoietic stem cells in the embryo. Her seminal contributions, widely recognized by the scientific community, have paved the way for generations of developmental hematologists questioning the origins of hematopoietic stem cells. After having demonstrated the intra-embryonic origin of hematopoietic stem cells, established the dual origin of the endothelial network in the embryo and revealed the hematopoietic function of the allantois in birds, she has switched to mammals and contributed to demonstrating that the aorta and allantois/placenta are new sites of hematopoietic production in the mouse embryo. The manifold insights generated by the pivotal work of Françoise Dieterlen-Lièvre have created multiple paradigm shifts which continue to challenge the field of developmental hematopoiesis.