Lung Marginated and Splenic Murine Resident Neutrophils Constitute Pioneers in Tissue-Defense During Systemic E. coli Challenge

The rapid response of neutrophils throughout the body to a systemic challenge is a critical first step in resolution of bacterial infection such as Escherichia coli (E. coli). Here we delineated the dynamics of this response, revealing novel insights into the molecular mechanisms using lung and spleen intravital microscopy and 3D ex vivo culture of living precision cut splenic slices in combination with fluorescent labelling of endogenous leukocytes. Within seconds after challenge, intravascular marginated neutrophils and lung endothelial cells (ECs) work cooperatively to capture pathogens. Neutrophils retained on lung ECs slow their velocity and aggregate in clusters that enlarge as circulating neutrophils carrying E. coli stop within the microvasculature. The absolute number of splenic neutrophils does not change following challenge; however, neutrophils increase their velocity, migrate to the marginal zone (MZ) and form clusters. Irrespective of their location all neutrophils capturing heat-inactivated E. coli take on an activated phenotype showing increasing surface CD11b. At a molecular level we show that neutralization of ICAM-1 results in splenic neutrophil redistribution to the MZ under homeostasis. Following challenge, splenic levels of CXCL12 and ICAM-1 are reduced allowing neutrophils to migrate to the MZ in a CD29-integrin dependent manner, where the enlargement of splenic neutrophil clusters is CXCR2-CXCL2 dependent. We show directly molecular mechanisms that allow tissue resident neutrophils to provide the first lines of antimicrobial defense by capturing circulating E. coli and forming clusters both in the microvessels of the lung and in the parenchyma of the spleen.

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Transcriptional regulation in model organisms: recent progress and clinical implications

Open Biology ◽

10.1098/rsob.190183 ◽

2019 ◽

Vol 9 (11) ◽

pp. 190183 ◽

Cited By ~ 14

Author(s):

Jiaqi Tang ◽

Zhenhua Xu ◽

Lianfang Huang ◽

Hui Luo ◽

Xiao Zhu

Keyword(s):

Transcriptional Regulation ◽

Molecular Mechanisms ◽

The Body ◽

Model Organisms ◽

Clinical Implications ◽

Regulation Mechanism ◽

Biological Behaviour ◽

E Coli ◽

Different Types

In this review, we will summarize model organisms used by scientists in the laboratory, including Escherichia coli , yeast, Arabidopsis thaliana , nematodes, Drosophila , zebrafish, mice and other animals. We focus on the progress in research exploring different types of E. coli in the human body, and the specific molecular mechanisms by which they play a role in humans. First, we discuss the specific transcriptional regulation mechanism of E. coli in cell development, maturation, ageing and longevity, as well as tumorigenesis and development. Then, we discuss how the synthesis of some important substances in cells is regulated and how this affects biological behaviour. Understanding and applying these mechanisms, presumably, can greatly improve the quality of people's lives as well as increase their lifespan. For example, some E. coli can activate certain cells by secreting insulin-like growth factor-1, thus activating the inflammatory response of the body, while other E. coli can inactivate the immune response of the body by secreting toxic factors.

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The Selective Progesterone Receptor Modulator Ulipristal Acetate Inhibits the Activity of the Glucocorticoid Receptor

The Journal of Clinical Endocrinology & Metabolism ◽

10.1210/clinem/dgz139 ◽

2019 ◽

Vol 105 (3) ◽

pp. 716-734 ◽

Cited By ~ 1

Author(s):

Benjamin Small ◽

Charles E F Millard ◽

Edwina P Kisanga ◽

Andreanna Burman ◽

Anika Anam ◽

...

Keyword(s):

Glucocorticoid Receptor ◽

Uterine Fibroid ◽

Target Genes ◽

Nuclear Translocation ◽

Ex Vivo ◽

Therapeutic Option ◽

The Body ◽

Dependent Manner ◽

Ulipristal Acetate

Abstract Context The selective progesterone modulator ulipristal acetate (ulipristal) offers a much-needed therapeutic option for the clinical management of uterine fibroids. Although ulipristal initially passed safety evaluations in Europe, postmarketing analysis identified cases of hepatic injury and failure, leading to restrictions on the long-term use of ulipristal. One of the factors potentially contributing to significant side effects with the selective progesterone modulators is cross-reactivity with other steroid receptors. Objective To determine whether ulipristal can alter the activity of the endogenous glucocorticoid receptor (GR) in relevant cell types. Design Immortalized human uterine fibroid cells (UtLM) and hepatocytes (HepG2) were treated with the synthetic glucocorticoid dexamethasone and/or ulipristal. Primary uterine fibroid tissue was isolated from patients undergoing elective gynecological surgery and treated ex vivo with dexamethasone and/or ulipristal. In vivo ulipristal exposure was performed in C57Bl/6 mice to measure the effect on basal gene expression in target tissues throughout the body. Results Dexamethasone induced the expression of established glucocorticoid-target genes period 1 (PER1), FK506 binding protein 51 (FKBP5), and glucocorticoid-induced leucine zipper (GILZ) in UtLM and HepG2 cells, whereas cotreatment with ulipristal blocked the transcriptional response to glucocorticoids in a dose-dependent manner. Ulipristal inhibited glucocorticoid-mediated phosphorylation, nuclear translocation, and DNA interactions of GR. Glucocorticoid stimulation of PER1, FKBP5, and GILZ was abolished by cotreatment with ulipristal in primary uterine fibroid tissue. The expression of glucocorticoid-responsive genes was decreased in the lung, liver, and uterus of mice exposed to 2 mg/kg ulipristal. Interestingly, transcript levels of Fkbp5 and Gilz were increased in the hippocampus and pituitary. Conclusions These studies demonstrate that ulipristal inhibits endogenous glucocorticoid signaling in human fibroid and liver cells, which is an important consideration for its use as a long-term therapeutic agent.

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Nicotinamide Enhances the Polyploidization of Primary Megakaryocytes.

Blood ◽

10.1182/blood.v106.11.1366.1366 ◽

2005 ◽

Vol 106 (11) ◽

pp. 1366-1366

Author(s):

Lisa M. Giammona ◽

Eleftherios Papoutsakis ◽

William M. Miller

Keyword(s):

Dna Content ◽

Molecular Mechanisms ◽

Ex Vivo ◽

Annexin V ◽

Dependent Manner ◽

Vitamin B3 ◽

Ploidy Levels ◽

High Ploidy

Abstract Megakaryocyte (Mk) maturation includes the development of polyploid cells via endomitosis. In vitro models of Mk differentiation can be used to gain a better understanding of the molecular mechanisms controlling this process. However, it is challenging to achieve ploidy levels in cultured human cells that are as high as those observed in vivo. Others have recently reported the use of chemical inhibitors to increase Mk ploidy (Lannutti et al., Blood 105:3875, 2005). Here, we show that nicotinamide (NIC), a form of vitamin B3, enhances the normal process of Mk polyploidization and leads to both a greater fraction of high ploidy cells and a greater degree of polyploidization. Human mobilized peripheral blood CD34+ cells were cultured in serum-free medium supplemented with thrombopoietin (TPO) to induce Mk differentiation. Beginning on day 5 of culture, cells were treated with nicotinamide (3 and 6.25 mM) and monitored for DNA content, growth, apoptosis, and surface marker expression. NIC treatment resulted in a greater fraction of Mks with high ploidy (DNA content greater than or equal to 8N). The ploidy of NIC treated cells continued to increase over the duration of the 13-day culture, whereas the ploidy of untreated cells peaked at day 9. On day 13 (8 days of NIC exposure), the percentages of high ploidy Mks for the untreated, 3 mM NIC, and 6.25 mM NIC conditions were 23%, 48%, and 63%, respectively. Furthermore, cells treated with NIC reached ploidy levels of 64N and 32N for 6.25 and 3 mM NIC, respectively, compared to 16N for untreated cells. NIC-treated cells also displayed dramatic differences in morphology - characterized by an increase in cell size, the presence of a more highly lobated nucleus, and an increased frequency of proplatelet-forming cells. Nicotinamide is known to inhibit poly(ADP-ribose) polymerase (PARP) and Sir2, which are both NAD+ dependent enzymes. Preliminary experiments show that PARP activity is low in cultured Mks and is not affected by addition of 6.25 mM NIC. Continued exposure (beginning at day 5) to the PARP inhibitors (and nicotinamide analogs) 3-aminobenzamide (3-AB) and benzamide at concentrations of 1, 3, and 6.25 mM was toxic to cells in a dose dependent manner. Interestingly, high doses of NIC (25 and 50 mM) were also toxic to cells. Remarkably, while Mk polyploidization and apoptosis are typically correlated, the increase in DNA content observed for NIC-treated cells occurred without significantly affecting the percentage of apoptotic Mks (assessed by Annexin V staining). These data suggest that it may be possible to partially decouple Mk apoptosis and polyploidization. Furthermore, while 6.25 mM NIC inhibited cell proliferation by ~35%, total expansion of cells cultured with 3 mM NIC was similar to that of untreated cells. This, combined with similar Mk commitment, as defined by a similar percentage of CD41+ cells, resulted in a greater overall number of high ploidy Mks in cultures treated with NIC. Since there is a direct correlation between Mk DNA content and platelet production (Mattia et al., Blood 99:888, 2002), these results suggest a possible therapeutic benefit of NIC for the management of thrombocytopenia. Similarly, NIC could also be used as an additive to ex vivo Mk cultures destined for transplantation. Figure Figure

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The EGFR-Inhibitor Erlotinib Induces Apoptosis in Neoplastic Cells of Myelodysplastic Syndrome (MDS) and Acute Myeloid Leukemia (AML), an Effect Determined by the Expression Level of Nucleophosmin (NPM).

Blood ◽

10.1182/blood.v108.11.856.856 ◽

2006 ◽

Vol 108 (11) ◽

pp. 856-856

Author(s):

Simone Boehrer ◽

Lionel Ades ◽

Claire Fabre ◽

Pierre Fenaux ◽

Guido Kroemer

Keyword(s):

Cell Lines ◽

Molecular Mechanisms ◽

Therapeutic Potential ◽

Ex Vivo ◽

Myeloid Cell ◽

Expression Level ◽

Apoptotic Cells ◽

Dependent Manner ◽

Egfr Inhibitor ◽

Down Regulation

Abstract Background: the epidermal-growth-factor-receptor (EGFR)-inhibitor erlotinib was rationally designed to antagonize the deregulated EGFR-activity in solid tumors. Abundant studies in these entities not only demonstrated clinical efficacy, but also a favorable toxicity profile. In particular the absence of hematopoietic toxicity prompted us to investigate the therapeutic potential of erlotinib in MDS and AML cells. Methods: We incubated ex vivo cells from patients with MDS (n=4, 2 lower risk and 2 higher risk) and AML (n=6, de novo: 3; post MDS: 3), as well as a broad spectrum of myeloid cell lines (P39, KG-1, HL-60, MV4-11, MOLM-13) with increasing dosages of erlotinib (1μM to 10μM). As controls (n=4) we used non-malignant CD34 + bone marrow cells. Before incubation, all ex vivo cells underwent CD34 + selection. Serial FACS-analyses of parameters determining apoptosis (DIOC/PI and AnnexinV/PI) were carried out over a maximum of 6 days. Results: We found that erlotinib was able to induce a considerable degree of apoptosis in MDS and AML cells. Although there was a high interindividual difference in sensitivity towards erlotinib, “responders” treated with 10μM erlotinib showed an increase of apoptotic cells between 20–30% after 72h, which reached a maximum of 60% on day 6. This apoptosis-inducing effect was achieved in a dose-dependent manner and not restricted to a specific entity. Noteworthy, erlotinib exhibited no toxicity towards non-neoplastic progenitor cells. Evaluating the molecular mechanisms determining sensitivity we showed that the apoptosis-inducing effect of erlotinib critically depended on the expression level of NPM. Thus erlotinib-resistant myeloid cell lines (i.e. P39) exhibited a higher epression of NPM than sensitive cell lines (i.e. KG-1). In addition, down-regulation of NPM by small-interfering RNA not only increased the apoptosis-inducing effect of erlotinib in sensitive cells, but moreover established sensitivity in otherwise erlotinib-resistant cells. Accordingly, siRNA-induced down-regulation of NPM in P39 cells elevated the percentage of apoptotic cells upon treatment with 10μM erlotinib by about 30% as compared to mock-transfected controls. Conclusion, we showed an off-target effect of erlotinib, as evidenced by its ability to induce apoptosis in EGFR-negative cells. Of particular interest is the observation that erlotinib induced apoptosis exclusively in neoplastic myeloid cells while sparing non-malignant progenitors. To the best of our knowledge, this is the first report providing evidence for the therapeutic potential of erlotinib in MDS and AML.

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Corticosterone Enhances the AMPK-Mediated Immunosuppressive Phenotype of Testicular Macrophages During Uropathogenic Escherichia coli Induced Orchitis

Frontiers in Immunology ◽

10.3389/fimmu.2020.583276 ◽

2020 ◽

Vol 11 ◽

Author(s):

Zhengguo Zhang ◽

Ziming Jiang ◽

Yiming Zhang ◽

Yu Zhang ◽

Yan Yan ◽

...

Keyword(s):

Molecular Mechanisms ◽

Critical Event ◽

M2 Macrophage ◽

Mouse Bone Marrow ◽

Dependent Manner ◽

E Coli ◽

And Function ◽

Amp Activated Protein Kinase ◽

Testicular Macrophages

Testicular macrophages (TM) play a central role in maintaining testicular immune privilege and protecting spermatogenesis. Recent studies showed that their immunosuppressive properties are maintained by corticosterone in the testicular interstitial fluid, but the underlying molecular mechanisms are unknown. In this study, we treated mouse bone marrow-derived macrophages (BMDM) with corticosterone (50 ng/ml) and uncovered AMP-activated protein kinase (AMPK) activation as a critical event in M2 polarization at the phenotypic, metabolic, and cytokine production level. Primary TM exhibited remarkably similar metabolic and phenotypic features to corticosterone-treated BMDM, which were partially reversed by AMPK-inhibition. In a murine model of uropathogenic E. coli-elicited orchitis, intraperitoneal injection with corticosterone (0.1mg/day) increased the percentage of M2 TM in vivo, in a partially AMPK-dependent manner. This study integrates the influence of corticosterone on M2 macrophage metabolic pathways, phenotype, and function, and highlights a promising new avenue for the development of innovative therapeutics for orchitis patients.

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Two-Photon Imaging of Cellular Activities in Oxygen Sensing Tissues

Microscopy and Microanalysis ◽

10.1017/s1431927608080847 ◽

2008 ◽

Vol 14 (6) ◽

pp. 519-525 ◽

Cited By ~ 2

Author(s):

Christoph Wotzlaw ◽

Utta Berchner-Pfannschmidt ◽

Joachim Fandrey ◽

Helmut Acker

Keyword(s):

Molecular Mechanisms ◽

Ex Vivo ◽

Oxygen Sensing ◽

Rat Kidney ◽

Hypoxia Inducible Factor ◽

The Body ◽

Cellular Functions ◽

Protein Protein Interaction ◽

Two Photon

AbstractThe cellular oxygen sensing system of the body ensures appropriate adaptation of cellular functions toward hypoxia by regulating gene expression and ion channel activity. Two-photon laser microscopy is an ideal tool to study and prove the relevance of the molecular mechanisms within oxygen sensing pathways on the cellular and complex tissue or organ level. Images of hypoxia inducible factor 1 (HIF-1) subunit nuclear mobility and protein-protein interaction in living cells, of hypoxia-induced changes in membrane potential and intracellular calcium of live ex vivo carotid bodies as well as of rat kidney proximal tubulus function in vivo, will be shown.

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The fate of methylmercury through the formation of bismethylmercury sulfide as an intermediate in mice

Scientific Reports ◽

10.1038/s41598-021-96579-y ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Yumi Abiko ◽

Yusuke Katayama ◽

Wenyang Zhao ◽

Sawako Horai ◽

Kenji Sakurai ◽

...

Keyword(s):

Ex Vivo ◽

Intraperitoneal Administration ◽

Distal Colon ◽

The Body ◽

Gas Chromatography Mass Spectrometry ◽

Dependent Manner ◽

Free System ◽

A Cell

AbstractA previous study by our group indicated that methylmercury (MeHg) is biotransformed to bismethylmercury sulfide [(MeHg)2S)] by interaction with reactive sulfur species (RSS) produced in the body. In the present study, we explored the transformation of MeHg to (MeHg)2S in the gut and the subsequent fate of (MeHg)2S in vitro and in vivo. An ex vivo experiment suggested the possibility of the extracellular transformation of MeHg to (MeHg)2S in the distal colon, and accordingly, the MeHg sulfur adduct was detected in the intestinal contents and feces of mice administered MeHg, suggesting that (MeHg)2S is formed through reactions between MeHg and RSS in the gut. In a cell-free system, we found that (MeHg)2S undergoes degradation in a time-dependent manner, resulting in the formation of mercury sulfide and dimethylmercury (DMeHg), as determined by X-ray diffraction and gas chromatography/mass spectrometry, respectively. We also identified DMeHg in the expiration after the intraperitoneal administration of (MeHg)2S to mice. Thus, our present study identified a new fate of MeHg through (MeHg)2S as an intermediate, which leads to conversion of volatile DMeHg in the body.

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Analytical and preparative biosynthesis of S100B recombinant protein using the pBT7-N-His vector system and preliminary studies of structure and function of this protein

Nauchno-prakticheskii zhurnal «Patogenez» ◽

10.25557/2310-0435.2018.04.161-164 ◽

2018 ◽

pp. 161-164

Author(s):

О.Л. Терёхина ◽

М.К. Нурбеков ◽

О.П. Дмитренко ◽

Д.М. Давыдов

Keyword(s):

Recombinant Protein ◽

Molecular Mechanisms ◽

The Body ◽

S100b Protein ◽

Vector System ◽

Diagnostic Systems ◽

E Coli ◽

Sds Page ◽

Bacterial Clone ◽

And Function

С целью исследований структуры и функций белка S100B в клетке и в тканях был проведен цикл работ по оптимизации экспрессии рекомбинантного белка (рекS100B) в E. coli. Проведены процедуры аналитической экспрессии рекS100B в составе рекомбинантной плазмиды pBT7-N-His-S100B03. При SDS-ПААГЭ лизатов клонов бактерий выявлена четко экспрессирующаяся полоса в 10 кДа, которая была идентифицирована как мономерная форма белка. Перспективы исследований рекS100B связаны с потенциальным его использованием для изучения тонких молекулярных механизмов PPI взаимодействий в системе S100B/RAGE рецептор как ключевого звена передачи сигналов в клетке и организме и в качестве перспективного объекта создания диагностических систем мониторинга состояний организма в норме и при патологии связанной с нарушениями регуляции гена и/или функций S100B белка. To study structure and functions of the S100B protein in cells and tissues, a series of studies was conducted to optimize the recombinant protein (recS100B) expression in E. coli. Procedures for analytical expression of recS100B in the pBT7-N-His-S100B03 recombinant plasmid were performed. In SDS-PAGE of bacterial clone lysate, a clear 10 kDa band expression was detected, which was identified as a monomeric form of the protein. Prospects for the S100B study are related with its potential use for investigating molecular mechanisms of PPI interactions in the S100B/RAGE system as a key signal transducer in the cell and body and as a promising object for developing diagnostic systems for monitoring the body state in normal and pathological conditions associated with impaired regulation of the gene and/or functions of the S100B protein.

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EspP, An Extracellular Serine Protease From Enterohemorrhagic E. Coli, Induces Coagulopathy In Human Whole Blood and Plasma

Blood ◽

10.1182/blood.v116.21.4416.4416 ◽

2010 ◽

Vol 116 (21) ◽

pp. 4416-4416

Author(s):

Kevin H.M. Kuo ◽

Shekeb Khan ◽

Elena Brnjac ◽

Emil F. Pai ◽

Alden E. Chesney

Keyword(s):

Serine Protease ◽

Whole Blood ◽

Ex Vivo ◽

Coagulation Factor ◽

Time Dependent ◽

Coagulation Cascade ◽

Factor V ◽

Dependent Manner ◽

E Coli ◽

Negative Controls

Abstract Abstract 4416 EspP (E. coli secreted serine protease, large plasmid encoded) is an extracellular serine protease produced by enterohemorrhagic E. coli (EHEC) O157:H7. Brunder et al. (Mol Microbiol 1997, 24:767–78) have shown that EspP cleaves, amongst other proteins, human coagulation factor V, and the authors hypothesized that it may contribute to the mucosal hemorrhage in patients with EHEC infection. We have since shown that EspP also cleaves factor VIII. Since the mechanism by which EHEC induces diarrhea-associated Hemolytic Uremic Syndrome (D+HUS) has not been fully elucidated, and EspP has been cited as a putative virulence factor in D+HUS, we investigated the role of EspP in primary and secondary hemostasis in the pathogenesis of D+HUS. Wild type EspP (EspPwt) and EspPS263A, where the serine at the active site was mutated to an alanine thereby abolishing its proteolytic activity, were expressed in the non-pathogenic E. coli host BL21(DE3) and purified by hydrophobic interaction and size-exclusion chromatography. EspPwt at 1.0 mg/mL was incubated for 0.5, 2.0 and 4.0 hours ex vivo with citrated plasma from 6 healthy adults. EspPS263A, bovine serum albumin (BSA) and phosphate buffer saline-glycerol (PBS-G) served as negative controls. PT, aPTT and TT were found to be significantly prolonged and activity of factors V, VII, VIII and XII were reduced in a time- and concentration-dependent manner (Figures 1 and Figure 2). When citrated plasma was incubated with 1 mg/mL EspPwt at 37°C for 4 hours, PT was prolonged by 23.2 +/− 3.8 s, aPTT by 41.6 +/− 8.3 s and TT by 6.1 +/− 0.6 s, relative to the negative controls. Factor V activity decreased by 0.82 +/− 0.14 U/mL, factor VII by 0.72 +/− 0.28 U/mL, factor VIII by 0.69 +/− 0.31 U/mL and factor XII by 0.36 +/− 0.09 U/mL, relative to the negative controls. Prothrombin activity was significantly reduced (0.16 +/− 0.08 U/mL) compared to all negative controls but remained above 0.75 U/mL. Factors IX, × and XI activity, and fibrinogen concentration were not significantly different from the controls. To determine whether any cellular components in whole blood contribute to EspP's effect on the coagulation cascade, the experiment was repeated using citrated whole blood in place of plasma during the incubation phase. Plasma was then recovered and analyzed. Similar results were observed. The results suggest that EspP has proteolytic activity against specific coagulation factors at least in an ex vivo setting. In patients with EHEC infection, EspP may contribute to the hemorrhagic diarrhea by impairing the coagulation cascade. Further studies are needed to determine whether EspP is able to induce coagulopathy in vivo and if so, whether induction of such a coagulopathic state may favour the entry of Shiga toxin into systemic circulation in patients with D+HUS. Figure 1 EspP prolongs PT, aPTT and TT in a time-dependent manner. Figure 1. EspP prolongs PT, aPTT and TT in a time-dependent manner. Figure 2 EspP reduces coagulation factor activity in a time-dependent manner. Figure 2. EspP reduces coagulation factor activity in a time-dependent manner. Disclosures: No relevant conflicts of interest to declare.

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Hematopoietic Differentiation of Human Pluripotent Stem Cells: HOX and GATA Transcription Factors as Master Regulators

Current Genomics ◽

10.2174/1389202920666191017163837 ◽

2019 ◽

Vol 20 (6) ◽

pp. 438-452 ◽

Cited By ~ 4

Author(s):

Khaled Alsayegh ◽

Lorena V. Cortés-Medina ◽

Gerardo Ramos-Mandujano ◽

Heba Badraiq ◽

Mo Li

Keyword(s):

Stem Cells ◽

Transcription Factors ◽

Pluripotent Stem Cells ◽

Molecular Mechanisms ◽

Ex Vivo ◽

The Body ◽

Hematopoietic Differentiation ◽

Hematopoietic Stem ◽

Master Regulators ◽

Wide Range

Numerous human disorders of the blood system would directly or indirectly benefit from therapeutic approaches that reconstitute the hematopoietic system. Hematopoietic stem cells (HSCs), either from matched donors or ex vivo manipulated autologous tissues, are the most used cellular source of cell therapy for a wide range of disorders. Due to the scarcity of matched donors and the difficulty of ex vivo expansion of HSCs, there is a growing interest in harnessing the potential of pluripotent stem cells (PSCs) as a de novo source of HSCs. PSCs make an ideal source of cells for regenerative medicine in general and for treating blood disorders in particular because they could expand indefinitely in culture and differentiate to any cell type in the body. However, advancement in deriving functional HSCs from PSCs has been slow. This is partly due to an incomplete understanding of the molecular mechanisms underlying normal hematopoiesis. In this review, we discuss the latest efforts to generate human PSC (hPSC)-derived HSCs capable of long-term engraftment. We review the regulation of the key transcription factors (TFs) in hematopoiesis and hematopoietic differentiation, the Homeobox (HOX) and GATA genes, and the interplay between them and microRNAs. We also propose that precise control of these master regulators during the course of hematopoietic differentiation is key to achieving functional hPSC-derived HSCs.

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