The ability to differentiate human-induced pluripotent stem cells (hiPSCs) efficiently into defined cardiac lineages, such as cardiomyocytes and cardiac endothelial cells, is crucial to study human... Show moreThe ability to differentiate human-induced pluripotent stem cells (hiPSCs) efficiently into defined cardiac lineages, such as cardiomyocytes and cardiac endothelial cells, is crucial to study human heart development and model cardiovascular diseases in vitro. The mechanisms underlying the specification of these cell types during human development are not well understood which limits fine-tuning and broader application of cardiac model systems. Here, we used the expression of ETV2, a master regulator of hematoendothelial specification in mice, to identify functionally distinct subpopulations during the co-differentiation of endothelial cells and cardiomyocytes from hiPSCs. Targeted analysis of single-cell RNA-sequencing data revealed differential ETV2 dynamics in the 2 lineages. A newly created fluorescent reporter line allowed us to identify early lineage-predisposed states and show that a transient ETV2-high-state initiates the specification of endothelial cells. We further demonstrated, unexpectedly, that functional cardiomyocytes can originate from progenitors expressing ETV2 at a low level. Our study thus sheds light on the in vitro differentiation dynamics of 2 important cardiac lineages. Show less
Chapter 2 investigated the generation of knockin mESC line in order to study the biallelic distribution of Nanog expression at the protein level. Chapter 3 investigated the generation of human ECs... Show moreChapter 2 investigated the generation of knockin mESC line in order to study the biallelic distribution of Nanog expression at the protein level. Chapter 3 investigated the generation of human ECs from hESCs using a spin-EB differentiation approach. Chapter 4 described the rst derivation of three human iPS cell lines in the Netherlands: two from healthy individuals and one from a patient with HHT. Chapter 5 investigated the use of hiPSC-EC as a model for studying HHT1 in vitro.Chapter 6 investigated the role of Gja5 that encodes for the gap junction protein Cx40 in the development of AVMs in the HHT2 mouse model. Show less
