Single Cell Resolution of Human Hematoendothelial Cells Defines Transcriptional Signatures of Hemogenic Endothelium

• Published in: Stem cells (Dayton, Ohio) Vol. 36; no. 2; pp. 206 - 217
• Main Authors: Angelos, Mathew G., Abrahante, Juan E., Blum, Robert H., Kaufman, Dan S.
• Format: Journal Article
• Language: English
• Published: United States Oxford University Press 01.02.2018
• Subjects: Antigens, Surface - metabolism; Biomarkers; CD34 antigen; CD43 antigen; CD45 antigen; CD73 antigen; Cell Differentiation - genetics; Cell Differentiation - physiology; Cells (biology); Cells, Cultured; Computational Biology; Developmental stages; Embryo cells; Embryonic Stem Cells - cytology; Embryonic Stem Cells - metabolism; Embryos; Endothelial cells; Endothelium; Flow Cytometry; Hemangioblasts - cytology; Hemangioblasts - metabolism; Hematopoiesis - genetics; Hematopoiesis - physiology; Hematopoietic stem cells; Hematopoietic Stem Cells - cytology; Hematopoietic Stem Cells - metabolism; Hemogenic endothelium; Human embryonic stem cells; Human hematopoiesis; Humans; Pluripotency; Pluripotent Stem Cells - cytology; Pluripotent Stem Cells - metabolism; Progenitor cells; Ribonucleic acid; RNA; Single cell RNA‐seq; Stem cells; Tissue inhibitor of metalloproteinase 3; Transcription; Human embryonic stem cells; Human hematopoiesis; Single cell RNA-seq; Hemogenic endothelium
• ISSN: 1066-5099; 1549-4918; 1549-4918
• DOI: 10.1002/stem.2739

Endothelial‐to‐hematopoietic transition (EHT) is an important stage in definitive hematopoietic development. However, the genetic mechanisms underlying human EHT remain poorly characterized. We performed single cell RNA‐seq using 55 hemogenic endothelial cells (HECs: CD31+CD144+CD41–CD43–CD45–CD73–RUNX1c+), 47 vascular endothelial cells without hematopoietic potential (non‐HE: CD31+CD144+CD41–CD43–CD45–CD73–RUNX1c–), and 35 hematopoietic progenitor cells (HPCs: CD34+CD43+RUNX1c+) derived from human embryonic stem cells (hESCs). HE and HP were enriched in genes implicated in hemogenic endothelial transcriptional networks, such as ERG, GATA2, and FLI. We found transcriptional overlap between individual HECs and HPCs; however, these populations were distinct from non‐HE. Further analysis revealed novel biomarkers for human HEC/HPCs, including TIMP3, ESAM, RHOJ, and DLL4. Collectively, we demonstrate that hESC‐derived HE and HP share a common developmental pathway, while non‐HE are more heterogeneous and transcriptionally distinct. Our findings provide a novel strategy to test new genetic targets and optimize the production of definitive hematopoietic cells from human pluripotent stem cells. Stem Cells 2018;36:206–217 Using a RUNX1c reporter hESC line, we derived functional hemogenic endothelium, non‐hemogenic endothelium, and early hematopoietic progenitor cells from embryoid bodies. With single‐cell RNA‐sequencing, we characterized the genetic signatures distinct to each population and further identified novel genetic targets that may be used to optimize production of definitive human hematopoietic cells from pluripotent stem cells.