Engraftable multilineage hematopoietic cells differentiated from induced human pluripotent stem cells

The production of hematopoietic stem cells (HSCs) from induced pluripotent stem cells (iPSCs) would have significant implications for medicine and biotechnology. We differentiated iPSCs to blood cells resembling the first repopulating HSCs of the human embryo. In immune deficient mice transplanted with iPSC-derived CD34+ cells, long term, low level bone marrow engraftment was seen in most animals. Although many animals were engrafted by myeloid, or myeloid and B lymphoid restricted progeny, 18% of mice receiving cells exposed to retinoids at day 3 of differentiation developed multilineage erythroid, myeloid and lymphoid cell engraftment (MLE), reflecting in vitro generation of HSCs or MPPs (termed iPSC-derived (i)HSCs). In a second cohort of mice, we observed in 36% of animals transplanted with cells receiving retinoids throughout differentiation. These studies identify conditions that yield engrafting iHSCs differentiated from human iPSCs and provide a foundation for the generation of cells for clinical translation.