Generation and Homing of iPSC-Derived Hematopoietic Cells In Vivo

Abstract

Extensive investigations by dozens of laboratories around the world over the past decade have failed to develop a reproducible and reliable way to differentiate human pluripotent stem cells such as embryonic stem cells (ESCs) or induced pluripotent stem cells (iPSCs) into hematopoietic stem cells (HSCs) that are functional both in vivo and in vitro. However, in this issue of Molecular Therapy, Suzuki et al. describe the use of iPSC-derived teratomas as in vivo bioreactors mimicking early embryos for the generation of engraftable HSC-like cells.1 The iPSC-derived HSC-like cells were shown to be present within the teratoma as well as within the bone marrow (BM) of teratoma-bearing mice. The teratoma-derived HSCs could also engraft and repopulate multiple hematopoietic lineages in mice following subsequent transplantation. These findings provide an important breakthrough in the generation of HSCs with in vivo engraftment capability from iPSCs,1,2 arguably the first evidence of in vivo biological function by iPSC-derived progeny cells.