Recent reports have shown that somatic cells, under appropriate culture conditions, could be directly reprogrammed to cardiac, hepatic, or neuronal phenotype by lineage-specific transcription factors. In this study, we demonstrate that both embryonic and adult somatic fibroblasts can be efficiently reprogrammed to clonal multilineage hematopoietic progenitors by the ectopic expression of the transcription factors ERG, GATA2, LMO2, RUNX1c, and SCL. These reprogrammed cells were stably expanded on stromal cells and possessed short-term reconstitution ability in vivo. Loss of p53 function facilitated reprogramming to blood, and p53−/− reprogrammed cells efficiently generated erythroid, megakaryocytic, myeloid, and lymphoid lineages. Genome-wide analyses revealed that generation of hematopoietic progenitors was preceded by the appearance of hemogenic endothelial cells expressing endothelial and hematopoietic genes. Altogether, our findings suggest that direct reprogramming could represent a valid alternative approach to the differentiation of embryonic stem cells (ESCs) or induced pluripotent stem cells (iPSCs) for disease modeling and autologous blood cell therapies.
•ERG, GATA2, LMO2, RUNX1c, and SCL reprogram fibroblasts to blood•Reprogrammed fibroblasts have multilineage hematopoietic potential•Loss of p53 increases efficiency and multilineage potential of reprogrammed cells•Generation of blood progenitors is preceded by the appearance of hemogenic cells
Batta et al. demonstrate that murine fibroblasts are reprogrammed to hematopoietic progenitors, with erythroid, megakaryocyte, and myeloid potential, by ectopic expression of hematopoietic transcription factors. Reprogramming efficiency is increased by loss of p53 function, and generation of blood cells is preceded by the appearance of hemogenic endothelium.