Abstract
The current progress using the human embryonic stem cell (hESC) model system has provided much insight into the early origins of the hematopoietic and endothelial lineages, particularly the elusive hemangioblast. Recently, the cellular hierarchy and molecular regulation controlling hematopoietic commitment have been further elucidated. These findings not only provide new insights into early human development, but also advance the knowledge required to develop techniques capable of generating a given cell type for potential clinical applications. This review will focus on the latest advances using the hESC model system, capitalizing on the well-established mouse embryonic stem cell model system, as a means to investigate the lineage commitment events underlying the early embryonic development of human hematopoietic and endothelial cells.