Differentiation of human embryonic stem cells into hematopoietic cells in vitro.

The ability of embryonic stem cells (ES) cells to form cells and tissues from all three germ layers can be exploited to generate cells that can be used to treat diseases. In particular, successful generation of hematopoietic cells from ES cells could provide safer and less immunogenic cells than bone cells, obviating the need for severe host preconditioning when transplanted across major histocompatibility complex barriers. To generate hematopoietic stem cells, protocols utilizing embryoid body (EB)-induced differentiation of human ES (hES) cells have been applied in the authors' laboratory. While this protocol results in targeted differentiation into hematopoietic cells, much remains to be done to improve these methods and make them more efficient.