Hematological malignancies account for ~10% of new cancer diagnoses in the US, and many require transplantation of multipotent hematopoietic stem cells (HSC) derived from allogeneic donors. Although HSC transplantation can greatly improve patient survival, the availability of matched donors is limited, and the procedure can result in life- threatening graft-vs-host disease. Ideally, patients would be transplanted with corrected autologous HSC. The recent discoveries of induced pluripotent stem (iPS) cells, and technology enabling their efficient genetic modification, transform this idea into a realistic therapeutic goal. However, one critical, and currently limiting, step toward this goal is the efficient derivation of HSC with long-term engraftment potential from patient- specific iPS cells. We have learned from murine studies that HSC are generated from specialized hemogenic endothelial cells. Studies of human embryos suggest that hemogenic endothelial cell specification is critical for human hematopoiesis, as well. Thus, understanding the molecular events that specify hemogenic endothelium is critically important for promoting the generation of HSC; its recapitulation in human stem cell systems may generate a source of HSC for clinical therapies. To begin to dissect the molecular regulation of this process, we defined the phenotype of hemogenic endothelial cells in major sites of embryonic blood production - yolk sac and aorta-gonad- mesonephros (AGM). We determined that retinoic acid (RA) signaling is essential for their development; RA deficient mutants exhibit endothelial hyper-proliferation, and do not develop hemogenic endothelium or generate HSC. We found that Notch signaling functions downstream of RA to regulate endothelial cell cycle progression and hemogenic specification in the yolk sac. With these results as a foundation, the current proposal aims to advance our knowledge of the field. Specifically, we will further elucidate the role of Notch signaling in hemogenic endothelial cell specification and define the signaling components involved in this process (Aim 1); determine the role of endothelial cell cycle control in hemogenic specification (Aim 2); and apply insights from our murine developmental studies to the formation of hemogenic endothelial cells, and HSC production, from human iPS-derived primordial endothelium (Aim 3).

Public Health Relevance

Blood vessels and blood cells development in parallel to form an intact circulatory system. We aim to understand how some endothelial cells, which line the lumen of blood vessels, become specialized to generate blood cells. We will also determine whether we can use this information from mouse development studies to direct the fate of human stem cells to become these blood-forming (hemogenic) endothelial cells that can serve as a source of blood cells for human clinical therapies.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Research Project (R01)
Project #
5R01HL128064-04
Application #
9431239
Study Section
Special Emphasis Panel (ZRG1)
Program Officer
Yang, Yu-Chung
Project Start
2015-04-01
Project End
2020-02-29
Budget Start
2018-03-01
Budget End
2020-02-29
Support Year
4
Fiscal Year
2018
Total Cost
Indirect Cost
Name
Yale University
Department
Internal Medicine/Medicine
Type
Schools of Medicine
DUNS #
043207562
City
New Haven
State
CT
Country
United States
Zip Code
Yosef, Nejla; Vadakkan, Tegy J; Park, June-Hee et al. (2018) The phenotypic and functional properties of mouse yolk-sac-derived embryonic macrophages. Dev Biol 442:138-154
Genet, Nafiisha; Bhatt, Neha; Bourdieu, Antonin et al. (2018) Multifaceted Roles of Connexin 43 in Stem Cell Niches. Curr Stem Cell Rep 4:1-12
Polacheck, William J; Kutys, Matthew L; Yang, Jinling et al. (2017) A non-canonical Notch complex regulates adherens junctions and vascular barrier function. Nature 552:258-262
Freyer, Laina; Hsu, Chih-Wei; Nowotschin, Sonja et al. (2017) Loss of Apela Peptide in Mice Causes Low Penetrance Embryonic Lethality and Defects in Early Mesodermal Derivatives. Cell Rep 20:2116-2130
Ceneri, Nicolle; Zhao, Lina; Young, Bryan D et al. (2017) Rac2 Modulates Atherosclerotic Calcification by Regulating Macrophage Interleukin-1? Production. Arterioscler Thromb Vasc Biol 37:328-340
Dejana, Elisabetta; Hirschi, Karen K; Simons, Michael (2017) The molecular basis of endothelial cell plasticity. Nat Commun 8:14361
Fuster, José J; MacLauchlan, Susan; Zuriaga, María A et al. (2017) Clonal hematopoiesis associated with TET2 deficiency accelerates atherosclerosis development in mice. Science 355:842-847
Hirschi, Karen K; Nicoli, Stefania; Walsh, Kenneth (2017) Hematopoiesis Lineage Tree Uprooted: Every Cell Is a Rainbow. Dev Cell 41:7-9
Sivarapatna, Amogh; Ghaedi, Mahboobe; Xiao, Yang et al. (2017) Engineered Microvasculature in PDMS Networks Using Endothelial Cells Derived from Human Induced Pluripotent Stem Cells. Cell Transplant 26:1365-1379
Fang, Jennifer S; Coon, Brian G; Gillis, Noelle et al. (2017) Shear-induced Notch-Cx37-p27 axis arrests endothelial cell cycle to enable arterial specification. Nat Commun 8:2149

Showing the most recent 10 out of 16 publications