Hematopoietic stem cells are defined by their ability to self-renew and differentiate through progenitor cell stages into all types of mature blood cells. Gene-targeting studies in mice have demonstrated that many genes are essential for the generation and function of hematopoietic stem and progenitor cells. For definitively analyzing the function of these cells, transplantation studies have to be performed. In this chapter, we describe methods to isolate and transplant fetal liver cells as well as how to analyze donor cell reconstitution. This protocol is tailored toward mouse models where embryonic lethality precludes analysis of adult hematopoiesis or where it is suspected that the function of fetal liver hematopoietic stem and progenitor cells is compromised.
