Robust differentiation of human pluripotent stem cells into endothelial cells via temporal modulation of ETV2 with modified mRNA

Abstract

Human induced pluripotent stem cell (h-iPSC)-derived endothelial cells (h-iECs) have become a valuable tool in regenerative medicine. However, current differentiation protocols remain inefficient and lack reliability. Here, we describe a method for rapid, consistent, and highly efficient generation of h-iECs. The protocol entails the delivery of modified mRNA encoding the transcription factor ETV2 at the intermediate mesodermal stage of differentiation. This approach reproducibly differentiated thirteen diverse h-iPSC lines into h-iECs with exceedingly high efficiency. In contrast, standard differentiation methods that relied on endogenous ETV2 were inefficient and notably inconsistent. Our h-iECs were functionally competent in many respects, including the ability to form perfused vascular networks in vivo. Importantly, timely activation of ETV2 was critical, and bypassing the mesodermal stage produced putative h-iECs with reduced expansion potential and inability to form functional vessels. Our protocol has broad applications and could reliably provide an unlimited number of h-iECs for vascular therapies.