Differentiation of embryonic stem cells into hematopoietic cells

Embryonic stern (ES) cells have been derived from the inner cell mass cells of blas-tocytes, and are totipotent or pluripotent cells, and can be chimerised into early embryo, and developed in vivo into many tissue specific cells including germ cells. In vitro, ES cells can differentiate into multicellular aggregates of differentiated and undifferentiated cells, termed embryoid bodies(EBs), when cultured in suspension without inhibitory factors of differentiation, including a wide variety of cell types, and can generate neural cells, vascular endotheliurn, muscle colls, and endodermal derivatives, etc. In addition, similar pluripotent cell lines have been derived from the primordial germ cells of the developing gonadal ridge in early embryos, termed embryonic germ (EG) cells. Here, we will review the differentiation of ES cells into hematopoietic cells. The growth and expression characteristics of these EB-derived cells suggest that they are relatively uncommitted precursor or progenitor cells. EB-derived hematopoietic cells may play a role in future transplantation therapies.