Overexpression of GATA2 Enhances Development and Maintenance of Human Embryonic Stem Cell-Derived Hematopoietic Stem Cell-like Progenitors

Abstract

Summary GATA2 is essential for the endothelial-to-hematopoietic transition (EHT) and generation of hematopoietic stem cells (HSCs). It is poorly understood how GATA2 controls the development of human pluripotent stem cell (hPSC)-derived HS-like cells. Here, using human embryonic stem cells (hESCs) in which GATA2 overexpression was induced by doxycycline (Dox), we elucidated the dual functions of GATA2 in definitive hematopoiesis before and after the emergence of CD34 + CD45 + CD90 + CD38 – HS-like cells. Specifically, GATA2 promoted expansion of hemogenic precursors via the EHT and then helped to maintain HS-like cells in a quiescent state by regulating cell cycle. RNA sequencing showed that hPSC-derived HS-like cells were very similar to human fetal liver-derived HSCs. Our findings will help to elucidate the mechanism that controls the early stages of human definitive hematopoiesis and may help to develop a strategy to generate hPSC-derived HSCs.

Multifaceted Actions of GFI1 and GFI1B in Hematopoietic Stem Cell Self-Renewal and Lineage Commitment

“…Cells have even been generated through processes that recapitulate in vitro the EHT that takes place in the AGM as a way to ensure acquisition of stemness to produce pluripotent HSCs with the capacity to colonize hematopoietic sites. However, these cells still lack a robust capacity to engraft in a host (Wang et al, 2005;Lengerke et al, 2009;Doulatov et al, 2013;Riddell et al, 2014;Ruiz et al, 2019;Zhou et al, 2019). The first experiment that succeeds to produce engraftable HSCs from iPS cells achieved this by driving differentiation in vivo through teratoma formation, but even in this case, the efficiency was very low with less than 1-2% of engraftment and relied on complex procedures and cocktails of cytokines to achieve this (Amabile et al, 2013;Suzuki et al, 2013;Philipp et al, 2018).…”

Alpha lipoic acid promotes development of hematopoietic progenitors derived from human embryonic stem cells by antagonizing ROS signals

“…N = 3 replicates; * P < 0.05, ** P < 0.01, *** P < 0.001, **** P < 0.0001; ns, not significant cytometry. The results showed that ALA-treated cocultures had more CD38 − CD90 + HSC phenotype-like cells 22 within the CD34 + CD43 + CD45 + populations ( Fig were counted. One thousand CD34 + CD43 + hematopoietic stem/progenitor cells on Day 14 were sorted into each replicate.…”

“…We have used cocultures of hPSCs with AGM-S3 stroma cells to explore the hematopoiesis of hPSCs. 17,21,22 Previous reports show that ALA affects intracellular ROS levels and apoptosis. 23,24 Upon irradiation, ALA protects HSCs in bone marrow and improves survival of animals 25 ; in addition, it can partially rescue the loss of HSCs caused by high ROS levels in GRK6 − /− mice.…”

“…As reported previously, HIF1A actsas an upstream regulator of RUNX1 and NOTCH signaling,46 and GFI1 and GFI1B act as downstream targets of RUNX1 45. Our findings showed that ALA might promote HEC development by affecting HIF1A-RUNX1 signaling.In the late stage cocultures, the number of hPSCs derived CD34 + CD43 + CD45 + hematopoietic stem/progenitor cells increased, and these hematopoietic stem/progenitor cells contained a high percentage of CD34 + CD43 + CD45 + CD90 + CD38 − HSC-like cells22 and a low percentage of differentiated progenitor cells (CMPs and EMPs) (…”

Overexpression of p21 Has Inhibitory Effect on Human Hematopoiesis by Blocking Generation of CD43＋ Cells via Cell-Cycle Regulation

“…Although it is an important member of the CKI family (24), the function of p21 in hematopoiesis has not yet been explored in an hESC-based in vitro system for hematopoiesis. We used the PB-Tet-on-OE vector system to establish an inducible p21/hESC line to characterize the roles of p21 (CDKN1A) in the AGM-S3 co-culture system using similar methods to those reported previously (10,18,25). This approach should confer much higher accuracy than a conventional expression system to test the effects of p21 on multiple stages, especially to uncover its roles in blockage effects of RUNX1b on hematopoiesis (10).…”