In Vitro Differentiation of Mouse ES Cells: Hematopoietic and Vascular Development

Mouse ES cells have been differentiated in vitro since the mid-1980s, and vasculogenesis and hematopoiesis were among the earliest developmental processes studied using this model. Vascular development during mouse ES cell differentiation involves two processes also used in vivo: (1) vasculogenesis, the assembly of mesodermal precursor cells called angioblasts and their differentiation into endothelial cells, and (2) angiogenesis, the expansion of vessels by migration and cell division of endothelial cells in vessels. This chapter describes protocols and assays that together provide a set of tools for quantitative analysis of vascular and hematopoietic parameters during ES cell differentiation. The in situ localization techniques also described here can be adapted to measure other cell biological parameters, such as the number of cytoplasmic extensions emanating from vascular tips. Moreover, it is just the start to utilize the imaging capability of the ES cell differentiation model to answer questions about the dynamic aspects of vascular and hematopoietic development. It is anticipated that these approaches will be combined with genetic and molecular biological tools (i.e., microarray analysis) in the future to provide new insights into vascular and hematopoietic development.