LAUSR

The human hematopoietic differentiation in vitro of human pluripotent stem cells (hPSCs) has provided new tools to elucidate the mechanisms of related genetic abnormalities, such as congenital diseases and acquired hematopoietic malignancies, and to discover new treatments. The differentiation can also be applied to developing a stable source of blood products for transfusion with minimal risk of several blood-borne infections. We previously proposed a method for hematopoietic progenitor cell (HPC) differentiation, the "hPSC-sac method", in which hPSCs are cocultured with C3H10T1/2 mouse stromal cells and mixed with a single cytokine, VEGF. The hPSC-sac method can differentiate hPSCs to multiple blood lineages. Here we describe improvements in the method by adding bFGF, TGFβ inhibitor and heparin to the culture, which increases the yield of CD34+CD43+ HPCs 50-fold compared with the original protocol. This revised hPSC-sac method is expected to contribute to the development of disease models and regenerative medicine using hematopoietic lineage cells.