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Iskander D, Karadimitris A, Roberts I. Harnessing Single-Cell Technologies in the Search for New Therapies for Diamond-Blackfan Anemia Syndrome. Exp Hematol 2024; 135:104235. [PMID: 38740323 DOI: 10.1016/j.exphem.2024.104235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2024] [Revised: 05/07/2024] [Accepted: 05/09/2024] [Indexed: 05/16/2024]
Abstract
The emergence of multiomic single-cell technologies over the last decade has led to improved insights into both normal hematopoiesis and its perturbation in a variety of hematological disorders. Diamond-Blackfan anemia (DBA) syndrome is one such disorder where single-cell assays have helped to delineate the cellular and molecular defects underlying the disease. DBA is caused by heterozygous loss-of-function germline variants in genes encoding ribosomal proteins (RPs). Despite the widespread role of ribosomes in hematopoiesis, the most frequent and severe cytopenia in DBA is anemia. In this review we discussed how single-cell studies, including clonogenic cell culture assays, fluorescence-activated cell sorting (FACS) and single-cell RNA sequencing (scRNA-seq), have led to insights into the pathogenesis of DBA. The main therapies are regular blood transfusions, glucocorticoids, or hematopoietic stem cell transplantation (HSCT) but all are associated with significant morbidity and mortality. We will therefore outline how single-cell studies can inform new therapies for DBA. Furthermore, we discussed how DBA serves as a useful model for understanding normal erythropoiesis in terms of its cellular hierarchy, molecular regulation during homeostasis, and response to "stress."
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Affiliation(s)
- Deena Iskander
- Centre for Haematology, Department of Immunology and Inflammation, Imperial College, London, United Kingdom; Department of Paediatric Haematology, St Mary's Hospital, Imperial College Healthcare Trust, London, United Kingdom.
| | - Anastasios Karadimitris
- Centre for Haematology, Department of Immunology and Inflammation, Imperial College, London, United Kingdom
| | - Irene Roberts
- MRC Molecular Haematology Unit, WIMM, University of Oxford, Oxford, United Kingdom; Department of Paediatrics, Children's Hospital and MHU, WIMM, Oxford University and John Radcliffe Hospital, Oxford, United Kingdom
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2
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Hamza E, Vallejo-Mudarra M, Ouled-Haddou H, García-Caballero C, Guerrero-Hue M, Santier L, Rayego-Mateos S, Larabi IA, Alvarez JC, Garçon L, Massy ZA, Choukroun G, Moreno JA, Metzinger L, Meuth VML. Indoxyl sulfate impairs erythropoiesis at BFU-E stage in chronic kidney disease. Cell Signal 2023; 104:110583. [PMID: 36596353 DOI: 10.1016/j.cellsig.2022.110583] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 12/16/2022] [Accepted: 12/29/2022] [Indexed: 01/01/2023]
Abstract
Chronic kidney disease (CKD) is a global health condition characterized by a progressive deterioration of kidney function. It is associated with high serum levels of uremic toxins (UT), such as Indoxyl Sulfate (IS), which may participate in the genesis of several uremic complications. Anemia is one of the major complications in CKD patients that contribute to cardiovascular disease, increase morbi-mortality, and is associated with a deterioration of kidney failure in these patients. Our study aimed to characterize the impact of IS on CKD-related erythropoiesis. Using cellular and pre-clinical models, we studied cellular and molecular effects of IS on the growth and differentiation of erythroid cells. First, we examined the effect of clinically relevant concentrations of IS (up to 250 μM) in the UT7/EPO cell line. IS at 250 μM increased apoptosis of UT7/EPO cells at 48 h compared to the control condition. We confirmed this apoptotic effect of IS in erythropoiesis in human primary CD34+ cells during the later stages of erythropoiesis. Then, in IS-treated human primary CD34+ cells and in a (5/6 Nx) mice model, a blockage at the burst-forming unit-erythroid (BFU-E) stage of erythropoiesis was also observed. Finally, IS deregulates a number of erythropoietic related genes such as GATA-1, Erythropoietin-Receptor (EPO-R), and β-globin. Our findings suggest that IS could affect cell viability and differentiation of erythroid progenitors by altering erythropoiesis and contributing to the development of anemia in CKD.
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Affiliation(s)
- Eya Hamza
- HEMATIM UR 4666, C.U.R.S, University of Picardie Jules Verne, CEDEX 1, 80025, Amiens, France
| | - Mercedes Vallejo-Mudarra
- Maimonides Biomedical Research Institute of Cordoba (IMIBIC), UGC Nephrology, Hospital Universitario Reina Sofía, 14004 Córdoba, Spain
| | - Hakim Ouled-Haddou
- HEMATIM UR 4666, C.U.R.S, University of Picardie Jules Verne, CEDEX 1, 80025, Amiens, France
| | - Cristina García-Caballero
- Maimonides Biomedical Research Institute of Cordoba (IMIBIC), UGC Nephrology, Hospital Universitario Reina Sofía, 14004 Córdoba, Spain
| | - Melania Guerrero-Hue
- Maimonides Biomedical Research Institute of Cordoba (IMIBIC), UGC Nephrology, Hospital Universitario Reina Sofía, 14004 Córdoba, Spain
| | - Laure Santier
- HEMATIM UR 4666, C.U.R.S, University of Picardie Jules Verne, CEDEX 1, 80025, Amiens, France
| | - Sandra Rayego-Mateos
- Cellular Biology in Renal Diseases Laboratory, IIS-Fundación Jiménez Díaz-Universidad Autónoma, Madrid, Spain
| | - Islam Amine Larabi
- Service de Pharmacologie-Toxicologie, Groupe Hospitalier Universitaires AP-HP, Paris-Saclay, Hôpital Raymond Poincaré, FHU Sepsis, 92380 Garches, France; MasSpecLab, Plateforme de spectrométrie de masse, Inserm U-1173, Université Paris Saclay (Versailles Saint Quentin-en-Yvelines), 78180 Montigny-le-Bretonneux, France
| | - Jean-Claude Alvarez
- Service de Pharmacologie-Toxicologie, Groupe Hospitalier Universitaires AP-HP, Paris-Saclay, Hôpital Raymond Poincaré, FHU Sepsis, 92380 Garches, France; MasSpecLab, Plateforme de spectrométrie de masse, Inserm U-1173, Université Paris Saclay (Versailles Saint Quentin-en-Yvelines), 78180 Montigny-le-Bretonneux, France
| | - Loïc Garçon
- HEMATIM UR 4666, C.U.R.S, University of Picardie Jules Verne, CEDEX 1, 80025, Amiens, France; Service d'Hématologie Biologique, Centre Hospitalier Universitaire, Amiens, France
| | - Ziad A Massy
- Centre for Research in Epidemiology and Population Health (CESP), University Paris-Saclay, University Versailles-Saint Quentin, Inserm UMRS 1018, Clinical Epidemiology Team, Villejuif, France; Department of Nephrology, CHU Ambroise Paré, APHP, 92104 Boulogne Billancourt, Paris Cedex, France
| | - Gabriel Choukroun
- Department of Nephrology Dialysis Transplantation, Amiens University Medical Center, F-80000 Amiens, France; MP3CV Laboratory, EA7517, Jules Verne University of Picardie, F-80000 Amiens, France
| | - Juan Antonio Moreno
- Maimonides Biomedical Research Institute of Cordoba (IMIBIC), UGC Nephrology, Hospital Universitario Reina Sofía, 14004 Córdoba, Spain; Biomedical Research Networking Center on Cardiovascular Diseases (CIBERCV), 28029 Madrid, Spain; Department of Cell Biology, Physiology and Immunology, University of Cordoba, 14014 Cordoba, Spain
| | - Laurent Metzinger
- HEMATIM UR 4666, C.U.R.S, University of Picardie Jules Verne, CEDEX 1, 80025, Amiens, France.
| | - Valérie Metzinger-Le Meuth
- HEMATIM UR 4666, C.U.R.S, University of Picardie Jules Verne, CEDEX 1, 80025, Amiens, France; INSERM UMRS 1148, Laboratory for Vascular Translational Science (LVTS), UFR SMBH, University Sorbonne Paris Nord, 93000 Bobigny, France
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3
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Haftorn KL, Denault WRP, Lee Y, Page CM, Romanowska J, Lyle R, Næss ØE, Kristjansson D, Magnus PM, Håberg SE, Bohlin J, Jugessur A. Nucleated red blood cells explain most of the association between DNA methylation and gestational age. Commun Biol 2023; 6:224. [PMID: 36849614 PMCID: PMC9971030 DOI: 10.1038/s42003-023-04584-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2022] [Accepted: 02/13/2023] [Indexed: 03/01/2023] Open
Abstract
Determining if specific cell type(s) are responsible for an association between DNA methylation (DNAm) and a given phenotype is important for understanding the biological mechanisms underlying the association. Our EWAS of gestational age (GA) in 953 newborns from the Norwegian MoBa study identified 13,660 CpGs significantly associated with GA (pBonferroni<0.05) after adjustment for cell type composition. When the CellDMC algorithm was applied to explore cell-type specific effects, 2,330 CpGs were significantly associated with GA, mostly in nucleated red blood cells [nRBCs; n = 2,030 (87%)]. Similar patterns were found in another dataset based on a different array and when applying an alternative algorithm to CellDMC called Tensor Composition Analysis (TCA). Our findings point to nRBCs as the main cell type driving the DNAm-GA association, implicating an epigenetic signature of erythropoiesis as a likely mechanism. They also explain the poor correlation observed between epigenetic age clocks for newborns and those for adults.
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Affiliation(s)
- Kristine L Haftorn
- Centre for Fertility and Health, Norwegian Institute of Public Health, Oslo, Norway.
- Institute of Health and Society, University of Oslo, Oslo, Norway.
| | - William R P Denault
- Centre for Fertility and Health, Norwegian Institute of Public Health, Oslo, Norway
- Department of Human Genetics, University of Chicago, Chicago, IL, 60637, USA
| | - Yunsung Lee
- Centre for Fertility and Health, Norwegian Institute of Public Health, Oslo, Norway
| | - Christian M Page
- Centre for Fertility and Health, Norwegian Institute of Public Health, Oslo, Norway
- Department of Physical Health and Ageing, Division of Mental and Physical Health, Norwegian Institute of Public Health, Oslo, Norway
| | - Julia Romanowska
- Centre for Fertility and Health, Norwegian Institute of Public Health, Oslo, Norway
- Department of Global Public Health and Primary Care, , University of Bergen, Bergen, Norway
| | - Robert Lyle
- Centre for Fertility and Health, Norwegian Institute of Public Health, Oslo, Norway
- Department of Medical Genetics, Oslo University Hospital and University of Oslo, Oslo, Norway
| | - Øyvind E Næss
- Institute of Health and Society, University of Oslo, Oslo, Norway
- Division of Mental and Physical Health, Norwegian Institute of Public Health, Oslo, Norway
| | - Dana Kristjansson
- Centre for Fertility and Health, Norwegian Institute of Public Health, Oslo, Norway
- Department of Genetics and Bioinformatics, Norwegian Institute of Public Health, Oslo, Norway
| | - Per M Magnus
- Centre for Fertility and Health, Norwegian Institute of Public Health, Oslo, Norway
| | - Siri E Håberg
- Centre for Fertility and Health, Norwegian Institute of Public Health, Oslo, Norway
| | - Jon Bohlin
- Centre for Fertility and Health, Norwegian Institute of Public Health, Oslo, Norway
- Division for Infection Control and Environmental Health, Department of Infectious Disease Epidemiology and Modelling, Norwegian Institute of Public Health, Oslo, Norway
| | - Astanand Jugessur
- Centre for Fertility and Health, Norwegian Institute of Public Health, Oslo, Norway
- Department of Global Public Health and Primary Care, , University of Bergen, Bergen, Norway
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4
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Jiang H, Wang M, Fu L, Zhong L, Liu G, Zheng Y, Chen X, Bian W. Liver transcriptome analysis and cortisol immune-response modulation in lipopolysaccharide-stimulated in channel catfish (Ictalurus punctatus). FISH & SHELLFISH IMMUNOLOGY 2020; 101:19-50. [PMID: 32184191 DOI: 10.1016/j.fsi.2020.03.024] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Revised: 02/28/2020] [Accepted: 03/11/2020] [Indexed: 06/10/2023]
Abstract
Channel catfish (Ictalurus punctatus) is an important aquaculture species in China. In channel catfish, diseases such as haemorrhagic, sepsis and tail-rot disease are all caused by bacteria as general in China. Most of the pathogenic bacteria are Gram-negative bacteria. Liver transcriptome analysis of the co-injection of cortisol and lipopolysaccharide (LPS) was performed in this study. Preliminary evidence from the results suggest that after the emergence of immune stress, cortisol will up-regulate the complement cascade pathway, down-regulate the coagulation cascade pathway, down-regulate the platelet activation pathway, down-regulate antigen presentation pathway, and show complex regulation relationship to inflammatory factors. At 12 h, the number of differential genes regulated by cortisol was about half less than the number of differential genes regulated by LPS. At 24 h, there was no significant difference between the number of differential genes regulated by cortisol and LPS, but the types of differential genes vary widely. KEGG enrichment analysis found that cortisol regulated LPS-stimulated immune responses mainly focus on cytokines, complement and coagulation cascades pathways, antigen presentation pathways, haematopoiesis, and inflammation. It is suggested that there may be some strategic choice in the regulation of immune response by cortisol. These results will help understand the pathogenesis and host defence system in bacterial disease caused by Gram-negative bacteria.
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Affiliation(s)
- Hucheng Jiang
- Freshwater Fisheries Research Institute of Jiangsu Province, Nanjing, 210017, China
| | - Minghua Wang
- Freshwater Fisheries Research Institute of Jiangsu Province, Nanjing, 210017, China
| | - Longlong Fu
- Freshwater Fisheries Research Institute of Jiangsu Province, Nanjing, 210017, China
| | - Liqiang Zhong
- Freshwater Fisheries Research Institute of Jiangsu Province, Nanjing, 210017, China
| | - Guoxing Liu
- Freshwater Fisheries Research Institute of Jiangsu Province, Nanjing, 210017, China
| | - You Zheng
- Freshwater Fisheries Research Institute of Jiangsu Province, Nanjing, 210017, China
| | - Xiaohui Chen
- Freshwater Fisheries Research Institute of Jiangsu Province, Nanjing, 210017, China.
| | - Wenji Bian
- Freshwater Fisheries Research Institute of Jiangsu Province, Nanjing, 210017, China.
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5
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Sibon D, Coman T, Rossignol J, Lamarque M, Kosmider O, Bayard E, Fouquet G, Rignault R, Topçu S, Bonneau P, Bernex F, Dussiot M, Deroy K, Laurent L, Callebert J, Launay JM, Georgin-Lavialle S, Courtois G, Maroteaux L, Vaillancourt C, Fontenay M, Hermine O, Côté F. Enhanced Renewal of Erythroid Progenitors in Myelodysplastic Anemia by Peripheral Serotonin. Cell Rep 2020; 26:3246-3256.e4. [PMID: 30893598 DOI: 10.1016/j.celrep.2019.02.071] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Revised: 12/30/2018] [Accepted: 02/20/2019] [Indexed: 10/27/2022] Open
Abstract
Tryptophan as the precursor of several active compounds, including kynurenine and serotonin, is critical for numerous important metabolic functions. Enhanced tryptophan metabolism toward the kynurenine pathway has been associated with myelodysplastic syndromes (MDSs), which are preleukemic clonal diseases characterized by dysplastic bone marrow and cytopenias. Here, we reveal a fundamental role for tryptophan metabolized along the serotonin pathway in normal erythropoiesis and in the physiopathology of MDS-related anemia. We identify, both in human and murine erythroid progenitors, a functional cell-autonomous serotonergic network with pro-survival and proliferative functions. In vivo studies demonstrate that pharmacological increase of serotonin levels using fluoxetine, a common antidepressant, has the potential to become an important therapeutic strategy in low-risk MDS anemia refractory to erythropoietin.
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Affiliation(s)
- David Sibon
- Institut Imagine, INSERM U1163, CNRS ERL 8254, Université Paris Descartes, Sorbonne Paris-Cité, Laboratoire d'Excellence GR-Ex, Paris, France
| | - Tereza Coman
- Institut Imagine, INSERM U1163, CNRS ERL 8254, Université Paris Descartes, Sorbonne Paris-Cité, Laboratoire d'Excellence GR-Ex, Paris, France; Département d'Hématologie, Gustave Roussy Cancer Campus Grand Paris, 94800 Villejuif, France
| | - Julien Rossignol
- Institut Imagine, INSERM U1163, CNRS ERL 8254, Université Paris Descartes, Sorbonne Paris-Cité, Laboratoire d'Excellence GR-Ex, Paris, France; Département d'Hématologie, Gustave Roussy Cancer Campus Grand Paris, 94800 Villejuif, France
| | - Mathilde Lamarque
- Institut Imagine, INSERM U1163, CNRS ERL 8254, Université Paris Descartes, Sorbonne Paris-Cité, Laboratoire d'Excellence GR-Ex, Paris, France
| | - Olivier Kosmider
- Institut Cochin, INSERM U1016, CNRS UMR 8104, Université Paris Descartes, Paris, APHP, Service d'Hématologie Biologique, Hôpitaux Universitaires Paris Centre-Cochin, Paris 75014, France
| | - Elisa Bayard
- Institut Imagine, INSERM U1163, CNRS ERL 8254, Université Paris Descartes, Sorbonne Paris-Cité, Laboratoire d'Excellence GR-Ex, Paris, France
| | - Guillemette Fouquet
- Institut Imagine, INSERM U1163, CNRS ERL 8254, Université Paris Descartes, Sorbonne Paris-Cité, Laboratoire d'Excellence GR-Ex, Paris, France
| | - Rachel Rignault
- Institut Imagine, INSERM U1163, CNRS ERL 8254, Université Paris Descartes, Sorbonne Paris-Cité, Laboratoire d'Excellence GR-Ex, Paris, France
| | - Selin Topçu
- Institut Imagine, INSERM U1163, CNRS ERL 8254, Université Paris Descartes, Sorbonne Paris-Cité, Laboratoire d'Excellence GR-Ex, Paris, France
| | - Pierre Bonneau
- Institut Imagine, INSERM U1163, CNRS ERL 8254, Université Paris Descartes, Sorbonne Paris-Cité, Laboratoire d'Excellence GR-Ex, Paris, France
| | - Florence Bernex
- Institut de Recherche en Cancérologie de Montpellier, Montpellier 34298, France; INSERM, U1194, Network of Experimental Histology, BioCampus, CNRS, UMS3426, Montpellier 34094, France
| | - Michael Dussiot
- Institut Imagine, INSERM U1163, CNRS ERL 8254, Université Paris Descartes, Sorbonne Paris-Cité, Laboratoire d'Excellence GR-Ex, Paris, France
| | - Kathy Deroy
- INRS-Institut Armand-Frappier and Center for Interdisciplinary Research on Well-Being, Health, Society and Environment, Montreal, QC H7V 1B7, Canada
| | - Laetitia Laurent
- INRS-Institut Armand-Frappier and Center for Interdisciplinary Research on Well-Being, Health, Society and Environment, Montreal, QC H7V 1B7, Canada
| | - Jacques Callebert
- Service de Biochimie, INSERM U942, Hôpital Lariboisière, 75010 Paris, France
| | - Jean-Marie Launay
- Service de Biochimie, INSERM U942, Hôpital Lariboisière, 75010 Paris, France
| | - Sophie Georgin-Lavialle
- Département de Médecine Interne, Hôpital Tenon, Université Pierre et Marie Curie, AP-HP, 4 rue de la Chine, 75020 Paris, France
| | - Geneviève Courtois
- Institut Imagine, INSERM U1163, CNRS ERL 8254, Université Paris Descartes, Sorbonne Paris-Cité, Laboratoire d'Excellence GR-Ex, Paris, France
| | - Luc Maroteaux
- INSERM UMR-S1270, Sorbonne Universités, Université Pierre et Marie Curie, Institut du Fer à Moulin, 75005 Paris, France
| | - Cathy Vaillancourt
- INRS-Institut Armand-Frappier and Center for Interdisciplinary Research on Well-Being, Health, Society and Environment, Montreal, QC H7V 1B7, Canada
| | - Michaela Fontenay
- Institut Cochin, INSERM U1016, CNRS UMR 8104, Université Paris Descartes, Paris, APHP, Service d'Hématologie Biologique, Hôpitaux Universitaires Paris Centre-Cochin, Paris 75014, France
| | - Olivier Hermine
- Institut Imagine, INSERM U1163, CNRS ERL 8254, Université Paris Descartes, Sorbonne Paris-Cité, Laboratoire d'Excellence GR-Ex, Paris, France; Department of Hematology, Hôpital Necker AP-HP, 75015 Paris, France
| | - Francine Côté
- Institut Imagine, INSERM U1163, CNRS ERL 8254, Université Paris Descartes, Sorbonne Paris-Cité, Laboratoire d'Excellence GR-Ex, Paris, France.
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Lakkavaram A, Lundie RJ, Do H, Ward AC, de Koning-Ward TF. Acute Plasmodium berghei Mouse Infection Elicits Perturbed Erythropoiesis With Features That Overlap With Anemia of Chronic Disease. Front Microbiol 2020; 11:702. [PMID: 32373101 PMCID: PMC7176981 DOI: 10.3389/fmicb.2020.00702] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Accepted: 03/26/2020] [Indexed: 12/21/2022] Open
Abstract
Severe malaria anemia is one of the most common causes of morbidity and mortality arising from infection with Plasmodium falciparum. The pathogenesis of malarial anemia is complex, involving both parasite and host factors. As mouse models of malaria also develop anemia, they can provide a useful resource to study the impact of Plasmodium infections and the resulting host innate immune response on erythropoiesis. In this study, we have characterized the bone marrow and splenic responses of the erythroid as well as other hematopoietic lineages after an acute infection of Balb/c mice with Plasmodium berghei. Such characterization of the hematopoietic changes is critical to underpin future studies, using knockout mice and transgenic parasites, to tease out the interplay between host genes and parasite modulators implicated in susceptibility to malaria anemia. P. berghei infection led to a clear perturbation of steady-state erythropoiesis, with the most profound defects in polychromatic and orthochromatic erythroblasts as well as erythroid colony- and burst-forming units (CFU-E and BFU-E), resulting in an inability to compensate for anemia. The perturbation in erythropoiesis was not attributable to parasites infecting erythroblasts and affecting differentiation, nor to insufficient erythropoietin (EPO) production or impaired activation of the Signal transducer and activator of transcription 5 (STAT5) downstream of the EPO receptor, indicating EPO-signaling remained functional in anemia. Instead, the results point to acute anemia in P. berghei-infected mice arising from increased myeloid cell production in order to clear the infection, and the concomitant release of pro-inflammatory cytokines and chemokines from myeloid cells that inhibit erythroid development, in a manner that resembles the pathophysiology of anemia of chronic disease.
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Affiliation(s)
- Asha Lakkavaram
- School of Medicine, Deakin University, Waurn Ponds, VIC, Australia
| | - Rachel J Lundie
- Infection and Immunity Program, Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Hang Do
- School of Medicine, Deakin University, Waurn Ponds, VIC, Australia
| | - Alister C Ward
- School of Medicine, Deakin University, Waurn Ponds, VIC, Australia
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7
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Zingariello M, Bardelli C, Sancillo L, Ciaffoni F, Genova ML, Girelli G, Migliaccio AR. Dexamethasone Predisposes Human Erythroblasts Toward Impaired Lipid Metabolism and Renders Their ex vivo Expansion Highly Dependent on Plasma Lipoproteins. Front Physiol 2019; 10:281. [PMID: 31019464 PMCID: PMC6458278 DOI: 10.3389/fphys.2019.00281] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Accepted: 03/04/2019] [Indexed: 02/04/2023] Open
Abstract
Cultures of stem cells from discarded sources supplemented with dexamethasone, a synthetic glucocorticoid receptor agonist, generate cultured red blood cells (cRBCs) in numbers sufficient for transfusion. According to the literature, however, erythroblasts generated with dexamethasone exhibit low enucleation rates giving rise to cRBCs that survive poorly in vivo. The knowledge that the glucocorticoid receptor regulates lipid metabolism and that lipid composition dictates the fragility of the plasma membrane suggests that insufficient lipid bioavailability restrains generation of cRBCs. To test this hypothesis, we first compared the expression profiling of erythroblasts generated with or without dexamethasone. This analysis revealed differences in expression of 55 genes, 6 of which encoding proteins involved in lipid metabolism. These were represented by genes encoding the mitochondrial proteins 3-Hydroxymethyl-3-Methylglutaryl-CoA lyase, upregulated, and 3-Oxoacid CoA-Transferase1 and glycerol-3-phosphate acyltransferase1, both downregulated, and the proteins ATP-binding cassette transporter1 and Hydroxysteroid-17-Beta-Dehydrogenase7, upregulated, and cAMP-dependent protein kinase catalytic subunit beta, downregulated. This profiling predicts that dexamethasone, possibly by interfering with mitochondrial functions, impairs the intrinsic lipid metabolism making the synthesis of the plasma membrane of erythroid cells depend on lipid-uptake from external sources. Optical and electron microscopy analyses confirmed that the mitochondria of erythroblasts generated with dexamethasone are abnormal and that their plasma membranes present pebbles associated with membrane ruptures releasing exosomes and micro-vesicles. These results indicate that the lipid supplements of media currently available are not adequate for cRBCs. To identify better lipid supplements, we determined the number of erythroblasts generated in synthetic media supplemented with either currently used liposomes or with lipoproteins purified from human plasma [the total lipoprotein fraction (TL) or its high (HDL), low (LDL) and very low (VLDL) density lipoprotein components]. Both LDL and VLDL generated numbers of erythroid cells 3-2-fold greater than that observed in controls. These greater numbers were associated with 2-3-fold greater amplification of erythroid cells due both to increased proliferation and to resistance to stress-induced death. In conclusion, dexamethasone impairs lipid metabolism making ex vivo expansion of erythroid cells highly dependent on lipid absorbed from external sources and the use of LDL and VLDL as lipid supplements improves the generation of cRBCs.
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Affiliation(s)
- Maria Zingariello
- Unit of Microscopic and Ultrastructural Anatomy, Department of Medicine, University Campus Bio-Medico, Rome, Italy
| | - Claudio Bardelli
- Department of Biomedical and NeuroMotor Sciences, Alma Mater Studiorum University, Bologna, Italy
| | - Laura Sancillo
- Unit of Microscopic and Ultrastructural Anatomy, Department of Medicine, University Campus Bio-Medico, Rome, Italy
| | | | - Maria Luisa Genova
- Department of Biomedical and NeuroMotor Sciences, Alma Mater Studiorum University, Bologna, Italy
| | | | - Anna Rita Migliaccio
- Department of Biomedical and NeuroMotor Sciences, Alma Mater Studiorum University, Bologna, Italy
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8
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Recio C, Guerra B, Guerra-Rodríguez M, Aranda-Tavío H, Martín-Rodríguez P, de Mirecki-Garrido M, Brito-Casillas Y, García-Castellano JM, Estévez-Braun A, Fernández-Pérez L. Signal transducer and activator of transcription (STAT)-5: an opportunity for drug development in oncohematology. Oncogene 2019; 38:4657-4668. [DOI: 10.1038/s41388-019-0752-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Revised: 01/09/2019] [Accepted: 02/03/2019] [Indexed: 02/08/2023]
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9
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10
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Hu J, Chen Q. The role of glucocorticoid receptor in prostate cancer progression: from bench to bedside. Int Urol Nephrol 2016; 49:369-380. [PMID: 27987128 DOI: 10.1007/s11255-016-1476-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Accepted: 12/03/2016] [Indexed: 10/20/2022]
Abstract
Glucocorticoids are a common class of adjuvant drugs for the treatment of castration-resistant prostate cancer (CRPC) combined with antitumour or antiandrogen agents. Glucocorticoids are administered clinically because they ameliorate toxic side effects and have inhibitory effects on adrenal androgen production, acting as a pituitary suppressant. However, their effects on prostate cancer cells especially the castration resistance prostate cancer cells are poorly defined. Glucocorticoids exert effects depend to a great extent on glucocorticoid receptor. In addition to a number of glucocorticoid receptor isoforms determined, it is found that the actions of glucocorticoids through GRα are influenced by other isoforms, such as GRβ and GRγ. Recently, studies found GR confers resistance to androgen deprivation therapy, and various glucocorticoids exert distinct efficacy in CRPC. In this review, we summarized the mechanisms of glucocorticoids and its clinical appliances on the basis of present evidence.
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Affiliation(s)
- Jieping Hu
- Department of Urology, The First Affiliated Hospital of Nanchang University, Nanchang, 330006, Jiangxi, China.
| | - Qingke Chen
- Department of Urology, The First Affiliated Hospital of Nanchang University, Nanchang, 330006, Jiangxi, China.
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11
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Sjögren SE, Siva K, Soneji S, George AJ, Winkler M, Jaako P, Wlodarski M, Karlsson S, Hannan RD, Flygare J. Glucocorticoids improve erythroid progenitor maintenance and dampen Trp53 response in a mouse model of Diamond-Blackfan anaemia. Br J Haematol 2015; 171:517-29. [PMID: 26305041 PMCID: PMC5014181 DOI: 10.1111/bjh.13632] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Accepted: 07/03/2015] [Indexed: 01/06/2023]
Abstract
Diamond-Blackfan anaemia (DBA) is a rare congenital disease causing severe anaemia and progressive bone marrow failure. The majority of patients carry mutations in ribosomal proteins, which leads to depletion of erythroid progenitors in the bone marrow. As many as 40% of all DBA patients receive glucocorticoids to alleviate their anaemia. However, despite their use in DBA treatment for more than half a century, the therapeutic mechanisms of glucocorticoids remain largely unknown. Therefore we sought to study disease specific effects of glucocorticoid treatment using a ribosomal protein s19 (Rps19) deficient mouse model of DBA. This study determines for the first time that a mouse model of DBA can respond to glucocorticoid treatment, similar to DBA patients. Our results demonstrate that glucocorticoid treatment reduces apoptosis, rescues erythroid progenitor depletion and premature differentiation of erythroid cells. Furthermore, glucocorticoids prevent Trp53 activation in Rps19-deficient cells- in a disease-specific manner. Dissecting the therapeutic mechanisms behind glucocorticoid treatment of DBA provides indispensible insight into DBA pathogenesis. Identifying mechanisms important for DBA treatment also enables development of more disease-specific treatments of DBA.
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Affiliation(s)
- Sara E Sjögren
- Department of Molecular Medicine and Gene Therapy, Lund University, Lund, Sweden.,Lund Stem Cell Centre, Lund University, Lund, Sweden
| | - Kavitha Siva
- Department of Molecular Medicine and Gene Therapy, Lund University, Lund, Sweden.,Lund Stem Cell Centre, Lund University, Lund, Sweden
| | - Shamit Soneji
- Lund Stem Cell Centre, Lund University, Lund, Sweden
| | - Amee J George
- Oncogenic Signalling and Growth Control Program, Peter MacCallum Cancer Centre, East Melbourne, Australia.,Sir Peter MacCallum Department of Oncology, The University of Melbourne, Parkville, Australia.,Department of Cancer Biology and Therapeutics, John Curtin School of Medical Research, The Australian National University, Canberra, Australia
| | - Marcus Winkler
- Department of Molecular Medicine and Gene Therapy, Lund University, Lund, Sweden.,Lund Stem Cell Centre, Lund University, Lund, Sweden
| | - Pekka Jaako
- Lund Stem Cell Centre, Lund University, Lund, Sweden.,Division of Molecular Haematology, Lund University, Lund, Sweden
| | - Marcin Wlodarski
- Division of Paediatric Haematology and Oncology, University of Freiburg, Freiburg, Germany
| | - Stefan Karlsson
- Department of Molecular Medicine and Gene Therapy, Lund University, Lund, Sweden.,Lund Stem Cell Centre, Lund University, Lund, Sweden
| | - Ross D Hannan
- Oncogenic Signalling and Growth Control Program, Peter MacCallum Cancer Centre, East Melbourne, Australia.,Sir Peter MacCallum Department of Oncology, The University of Melbourne, Parkville, Australia.,Department of Cancer Biology and Therapeutics, John Curtin School of Medical Research, The Australian National University, Canberra, Australia
| | - Johan Flygare
- Department of Molecular Medicine and Gene Therapy, Lund University, Lund, Sweden.,Lund Stem Cell Centre, Lund University, Lund, Sweden
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12
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Falchi M, Varricchio L, Martelli F, Masiello F, Federici G, Zingariello M, Girelli G, Whitsett C, Petricoin EF, Moestrup SK, Zeuner A, Migliaccio AR. Dexamethasone targeted directly to macrophages induces macrophage niches that promote erythroid expansion. Haematologica 2014; 100:178-87. [PMID: 25533803 DOI: 10.3324/haematol.2014.114405] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Cultures of human CD34(pos) cells stimulated with erythroid growth factors plus dexamethasone, a model for stress erythropoiesis, generate numerous erythroid cells plus a few macrophages (approx. 3%; 3:1 positive and negative for CD169). Interactions occurring between erythroblasts and macrophages in these cultures and the biological effects associated with these interactions were documented by live phase-contrast videomicroscopy. Macrophages expressed high motility interacting with hundreds/thousands of erythroblasts per hour. CD169(pos) macrophages established multiple rapid 'loose' interactions with proerythroblasts leading to formation of transient erythroblastic island-like structures. By contrast, CD169(neg) macrophages established 'tight' interactions with mature erythroblasts and phagocytosed these cells. 'Loose' interactions of CD169(pos) macrophages were associated with proerythroblast cytokinesis (the M phase of the cell cycle) suggesting that these interactions may promote proerythroblast duplication. This hypothesis was tested by experiments that showed that as few as 103 macrophages significantly increased levels of 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide incorporation frequency in S/G2/M and cytokinesis expressed by proerythroblasts over 24 h of culture. These effects were observed also when macrophages were co-cultured with dexamethasone directly conjugated to a macrophage-specific CD163 antibody. In conclusion, in addition to promoting proerythroblast proliferation directly, dexamethasone stimulates expansion of these cells indirectly by stimulating maturation and cytokinesis supporting activity of macrophages.
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Affiliation(s)
- Mario Falchi
- National AIDS Center, New York, NY, USA Tisch Cancer Institute, Mount Sinai School of Medicine, New York, NY, USA
| | - Lilian Varricchio
- Tisch Cancer Institute, Mount Sinai School of Medicine, New York, NY, USA
| | - Fabrizio Martelli
- Tisch Cancer Institute, Mount Sinai School of Medicine, New York, NY, USA Hematology/Oncology and Molecular Medicine, Istituto Superiore di Sanità, Rome, Italy
| | - Francesca Masiello
- Hematology/Oncology and Molecular Medicine, Istituto Superiore di Sanità, Rome, Italy
| | - Giulia Federici
- Regina Elena National Cancer Institute, Rome, Italy Hematology/Oncology and Molecular Medicine, Istituto Superiore di Sanità, Rome, Italy
| | | | | | - Carolyn Whitsett
- Kings County Hospital and Downstate Medical Center, Brooklyn, NY, USA
| | - Emanuel F Petricoin
- Center for Applied Proteomics and Molecular Medicine, George Mason University, Manassas, VA, USA
| | - Søren Kragh Moestrup
- Department of Biomedicine, University of Aarhus, Aarhus C, Denmark Institute of Molecular Medicine, University of Souther Denmark, Denmark
| | - Ann Zeuner
- Hematology/Oncology and Molecular Medicine, Istituto Superiore di Sanità, Rome, Italy
| | - Anna Rita Migliaccio
- Tisch Cancer Institute, Mount Sinai School of Medicine, New York, NY, USA Hematology/Oncology and Molecular Medicine, Istituto Superiore di Sanità, Rome, Italy
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13
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Varricchio L, Migliaccio AR. The role of glucocorticoid receptor (GR) polymorphisms in human erythropoiesis. AMERICAN JOURNAL OF BLOOD RESEARCH 2014; 4:53-72. [PMID: 25755906 PMCID: PMC4348794] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Received: 10/21/2014] [Accepted: 11/21/2014] [Indexed: 06/04/2023]
Abstract
Glucocorticoids are endogenous steroid hormones that regulate several biological functions including proliferation, differentiation and apoptosis in numerous cell types in response to stress. Synthetic glucocorticoids, such as dexamethasone (Dex) are used to treat a variety of diseases ranging from allergy to depression. Glucocorticoids exert their effects by passively entering into cells and binding to a specific Glucocorticoid Receptor (GR) present in the cytoplasm. Once activated by its ligand, GR may elicit cytoplasmic (mainly suppression of p53), and nuclear (regulation of transcription of GR responsive genes), responses. Human GR is highly polymorphic and may encode > 260 different isoforms. This polymorphism is emerging as the leading cause for the variability of phenotype and response to glucocorticoid therapy observed in human populations. Studies in mice and clinical observations indicate that GR controls also the response to erythroid stress. This knowledge has been exploited in-vivo by using synthetic GR agonists for treatment of the erythropoietin-refractory congenic Diamond Blackfan Anemia and in-vitro to develop culture conditions that may theoretically generate red cells in numbers sufficient for transfusion. However, the effect exerted by GR polymorphism on the variability of the phenotype of genetic and acquired erythroid disorders observed in the human population is still poorly appreciated. This review will summarize current knowledge on the biological activity of GR and of its polymorphism in non-hematopoietic diseases and discuss the implications of these observations for erythropoiesis.
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Affiliation(s)
- Lilian Varricchio
- Tisch Cancer Institute, Mount Sinai School of MedicineNew York, NY 10029, USA
| | - Anna Rita Migliaccio
- Tisch Cancer Institute, Mount Sinai School of MedicineNew York, NY 10029, USA
- Istituto Superiore di Sanita’ Viale Regina Elena 299Italy
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14
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15
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Abstract
β-thalassemia is an inherited disorder due to mutations found in the β-globin gene, leading to anemia and requiring sporadic or chronic blood transfusions for survival. Without proper chelation, β-thalassemia results in iron overload. Ineffective erythropoiesis can lead to iron overload even in untransfused patients who are affected by β-thalassemia intermedia. Better understanding of the molecular biologic aspects of this disorder has led to improvements in population screening and prenatal diagnosis, which, in turn, have led to dramatic reductions in the number of children born with β-thalassemia major in the Mediterranean littoral. However, as a consequence of decreases in neonatal and childhood mortality in other geographical areas, β-thalassemia has become a worldwide clinical problem. A number of unsolved pathophysiological issues remain, such as ineffective erythropoieis, abnormal iron absorption, oxidative stress, splenomegaly and thrombosis. In the last few years, novel studies have the potential to introduce new therapeutic approaches that might reduce these problems and limit the need for blood transfusion.
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Affiliation(s)
- Stefano Rivella
- Weill College Medical Center, Department of Pediatrics, Division of Hematology, Oncology, 515 E 71st Street, S702, New York, NY 10021, USA, Tel.: +1 212 746 4941, ,
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16
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Varricchio L, Tirelli V, Masselli E, Ghinassi B, Saha N, Besmer P, Migliaccio AR. The expression of the glucocorticoid receptor in human erythroblasts is uniquely regulated by KIT ligand: implications for stress erythropoiesis. Stem Cells Dev 2012; 21:2852-65. [PMID: 22533504 PMCID: PMC3623384 DOI: 10.1089/scd.2011.0676] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2011] [Accepted: 04/25/2012] [Indexed: 12/20/2022] Open
Abstract
Studies in mice indicated that activation of the erythroid stress pathway requires the presence of both soluble KIT ligand (KITL) and the glucocorticoid receptor (GR). To clarify the relative role of KITL and GR in stress erythropoiesis in humans, the biological activities of soluble full length- (fl-, 26-190 aa), carboxy-terminus truncated (tr-, 26-162 aa) human (hKITL) and murine (mKITL) KITL in cultures of cord blood (CB) mononuclear cells (MNCs) and CD34(pos) cells that mimic either steady state (growth factors alone) or stress (growth factors plus dexamethasone [DXM]) erythropoeisis were investigated. In steady state cultures, the KITLs investigated were equally potent in sustaining growth of hematopoietic colonies and expansion of megakaryocytes (MK) and erythroid precursors (EBs). By contrast, under stress erythropoiesis conditions, fl-hKITL generated greater numbers of EBs (fold increase [FI]=140) than tr-hKITL or mKITL (FI=20-40). Flow cytometric analyses indicated that only EBs generated with fl-hKITL remained immature (>70% CD36(pos)/CD235a(neg/low)), and therefore capable to proliferate, until day 8-12 in response to DXM. Signaling studies indicated that all KITLs investigated induced EBs to phosphorylate signal transducer and activator of transcription 5 (STAT5) but that extracellular-signaling-regulated-kinases (ERK) activation was observed mainly in the presence of fl-hKITL. EBs exposed to fl-hKITL also expressed higher levels of GRα than those exposed to mKITL (and tr-hKITL) which were reduced upon exposure to the ERK inhibitor U0126. These data reveal a unique requirement for fl-hKITL in the upregulation of GRα and optimal EB expansion in cultures that mimic stress erythropoiesis.
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Affiliation(s)
- Lilian Varricchio
- Tisch Cancer Institute, Mount Sinai School of Medicine, New York, New York
| | - Valentina Tirelli
- Hematology/Oncology and Molecular Medicine, Istituto Superiore di Sanita', Rome, Italy
| | - Elena Masselli
- Tisch Cancer Institute, Mount Sinai School of Medicine, New York, New York
| | - Barbara Ghinassi
- Tisch Cancer Institute, Mount Sinai School of Medicine, New York, New York
| | - Nayanendu Saha
- Structural Biology and Developmental Biology Program, Sloan Kettering Institute, New York, New York
| | - Peter Besmer
- Structural Biology and Developmental Biology Program, Sloan Kettering Institute, New York, New York
| | - Anna Rita Migliaccio
- Tisch Cancer Institute, Mount Sinai School of Medicine, New York, New York
- Hematology/Oncology and Molecular Medicine, Istituto Superiore di Sanita', Rome, Italy
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17
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Porpiglia E, Hidalgo D, Koulnis M, Tzafriri AR, Socolovsky M. Stat5 signaling specifies basal versus stress erythropoietic responses through distinct binary and graded dynamic modalities. PLoS Biol 2012; 10:e1001383. [PMID: 22969412 PMCID: PMC3433736 DOI: 10.1371/journal.pbio.1001383] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2012] [Accepted: 07/20/2012] [Indexed: 11/26/2022] Open
Abstract
Stat5 signaling in erythroblasts can assume either a binary, low-intensity form,
essential for basal erythropoiesis, or a graded, high-intensity response,
restricted to early erythroblasts and to erythropoietic stress. Erythropoietin (Epo)-induced Stat5 phosphorylation (p-Stat5) is essential for
both basal erythropoiesis and for its acceleration during hypoxic stress. A key
challenge lies in understanding how Stat5 signaling elicits distinct functions
during basal and stress erythropoiesis. Here we asked whether these distinct
functions might be specified by the dynamic behavior of the Stat5 signal. We
used flow cytometry to analyze Stat5 phosphorylation dynamics in primary
erythropoietic tissue in vivo and in vitro, identifying two signaling
modalities. In later (basophilic) erythroblasts, Epo stimulation triggers a low
intensity but decisive, binary (digital) p-Stat5 signal. In early erythroblasts
the binary signal is superseded by a high-intensity graded (analog) p-Stat5
response. We elucidated the biological functions of binary and graded Stat5
signaling using the EpoR-HM mice, which express a “knocked-in” EpoR
mutant lacking cytoplasmic phosphotyrosines. Strikingly, EpoR-HM mice are
restricted to the binary signaling mode, which rescues these mice from fatal
perinatal anemia by promoting binary survival decisions in erythroblasts.
However, the absence of the graded p-Stat5 response in the EpoR-HM mice prevents
them from accelerating red cell production in response to stress, including a
failure to upregulate the transferrin receptor, which we show is a novel stress
target. We found that Stat5 protein levels decline with erythroblast
differentiation, governing the transition from high-intensity graded signaling
in early erythroblasts to low-intensity binary signaling in later erythroblasts.
Thus, using exogenous Stat5, we converted later erythroblasts into
high-intensity graded signal transducers capable of eliciting a downstream
stress response. Unlike the Stat5 protein, EpoR expression in erythroblasts does
not limit the Stat5 signaling response, a non-Michaelian paradigm with
therapeutic implications in myeloproliferative disease. Our findings show how
the binary and graded modalities combine to generate high-fidelity Stat5
signaling over the entire basal and stress Epo range. They suggest that dynamic
behavior may encode information during STAT signal transduction. Hormone signaling through the erythropoietin (Epo) pathway is required both for
the continuous replacement of red blood cells (RBCs) that are lost through aging
(a process known as "basal erythropoiesis") and to boost tissue oxygen when
bleeding, in anemia or at high altitude ("stress erythropoiesis"). A key
challenge lies in understanding how extracellular Epo concentration is
translated into different intracellular signals that promote transcription of
proteins that are specific to basal versus stress erythropoiesis. Binding of Epo
to its receptor EpoR on the surface of an erythroblast (the precursors of RBCs)
triggers the addition of phosphates to a target protein Stat5; the
phosphorylated Stat5 becomes activated and induces transcription. We show that
the dynamic properties of the Stat5 activation signal convey additional
information that specifies either basal or stress responses. During basal
conditions, the Stat5 signal is low and binary in nature—an on/off
switch-like response. Stress, on the other hand, triggers a distinct Stat5
response consisting of a highintensity signal that increases in a graded fashion
with rising Epo concentration. We found that a mouse bearing a truncated EpoR is
restricted to the low-intensity binary Stat5 signal and correspondingly fails to
initiate stress erythropoiesis. Ultimately, it is the Stat5 protein level in
erythroblasts that determines their ability to generate the high-intensity
graded Stat5 signal in response to high Epo. These findings have therapeutic
potential: targeting Stat5's high-intensity graded signal may inhibit its
aberrant function in blood cell cancers without affecting its important binary
response in normal cells.
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Affiliation(s)
- Ermelinda Porpiglia
- Department of Pediatrics and Department of
Cancer Biology, University of Massachusetts Medical School, Worcester,
Massachusetts, United States of America
| | - Daniel Hidalgo
- Department of Pediatrics and Department of
Cancer Biology, University of Massachusetts Medical School, Worcester,
Massachusetts, United States of America
| | - Miroslav Koulnis
- Department of Pediatrics and Department of
Cancer Biology, University of Massachusetts Medical School, Worcester,
Massachusetts, United States of America
| | - Abraham R. Tzafriri
- CBSET Inc., Department of Applied Sciences,
Lexington, Massachusetts, United States of America
| | - Merav Socolovsky
- Department of Pediatrics and Department of
Cancer Biology, University of Massachusetts Medical School, Worcester,
Massachusetts, United States of America
- * E-mail:
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18
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Jewell CM, Scoltock AB, Hamel BL, Yudt MR, Cidlowski JA. Complex human glucocorticoid receptor dim mutations define glucocorticoid induced apoptotic resistance in bone cells. Mol Endocrinol 2011; 26:244-56. [PMID: 22174376 DOI: 10.1210/me.2011-1116] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
A mutation in the D-loop of the second zinc finger of the DNA-binding domain of the human glucocorticoid receptor (hGR), A458T (GR(dim)), has been suggested to be essential for dimerization and DNA binding of the GR, and genetically altered GR(dim) mice survive, whereas murine GR knockout mice die. Interestingly, thymocytes isolated from the GR(dim) mice were reported to be resistant to glucocorticoid-induced apoptosis. To further evaluate the dim mutations in glucocorticoid-induced apoptosis, we stably expressed either the hGR(dim) (A458T) or the hGR(dim4) (A458T, R460D, D462C, and N454D) mutant receptors in human osteosarcoma (U-2 OS) cells that are devoid of hGR and unresponsive to glucocorticoids. We analyzed these cell lines by comparison with a stable expression hGRα U-2 OS cell line, which undergoes apoptosis after glucocorticoid treatment. Transient reporter gene assays with glucocorticoid response element-driven vectors revealed that the hGR(dim) mutation had diminished steroid responsiveness and cells carrying the hGR(dim4) mutation were unresponsive to steroid, whereas glucocorticoid-induced nuclear factor κB repression was unaffected by either mutation. Interestingly, both the hGR(dim) and hGR(dim4) receptors readily formed dimers as measured by immunoprecipitation. Examination of GR-mediated apoptosis showed that hGR(dim) cells were only partially resistant to apoptosis, whereas hGR(dim4) cells were completely resistant to glucocorticoid-induced cell death despite remaining sensitive to other apoptotic stimuli. Global gene expression analysis revealed that hGR(dim4) cells widely regulated gene expression but differentially regulated apoptotic mRNA when compared with cells expressing wild-type hGRα. These studies challenge conclusions drawn from previous studies of GR dim mutants.
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Affiliation(s)
- Christine M Jewell
- National Institute of Environmental Health Sciences/National Institutes of Health, Laboratory of Signal Transduction, Research Triangle Park, North Carolina 27709, USA.
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19
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Migliaccio AR, Masselli E, Varricchio L, Whitsett C. Ex-vivo expansion of red blood cells: how real for transfusion in humans? Blood Rev 2011; 26:81-95. [PMID: 22177597 DOI: 10.1016/j.blre.2011.11.002] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Blood transfusion is indispensable for modern medicine. In developed countries, the blood supply is adequate and safe but blood for alloimmunized patients is often unavailable. Concerns are increasing that donations may become inadequate in the future as the population ages prompting a search for alternative transfusion products. Improvements in culture conditions and proof-of-principle studies in animal models have suggested that ex-vivo expanded red cells may represent such a product. Compared to other cell therapies transfusion poses the unique challenge of requiring great cell doses (2.5×10(12) cells vs 10(7) cells). Although production of such cell numbers is theoretically possible, current technologies generate red cells in numbers sufficient only for safety studies. It is conceived that by the time these studies will be completed, technical barriers to mass cell production will have been eliminated making transfusion with ex-vivo generated red cells a reality.
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Affiliation(s)
- Anna Rita Migliaccio
- The Tisch Cancer Institute and Myeloproliferative Disease Research Consortium (MPD-RC), Mount Sinai School of Medicine, New York, NY 10029, USA.
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Contrasting dynamic responses in vivo of the Bcl-xL and Bim erythropoietic survival pathways. Blood 2011; 119:1228-39. [PMID: 22086418 DOI: 10.1182/blood-2011-07-365346] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Survival signaling by the erythropoietin (Epo) receptor (EpoR) is essential for erythropoiesis and for its acceleration in hypoxic stress. Several apparently redundant EpoR survival pathways were identified in vitro, raising the possibility of their functional specialization in vivo. Here we used mouse models of acute and chronic stress, including a hypoxic environment and β-thalassemia, to identify two markedly different response dynamics for two erythroblast survival pathways in vivo. Induction of the antiapoptotic protein Bcl-x(L) is rapid but transient, while suppression of the proapoptotic protein Bim is slower but persistent. Similar to sensory adaptation, however, the Bcl-x(L) pathway "resets," allowing it to respond afresh to acute stress superimposed on a chronic stress stimulus. Using "knock-in" mouse models expressing mutant EpoRs, we found that adaptation in the Bcl-x(L) response occurs because of adaptation of its upstream regulator Stat5, both requiring the EpoR distal cytoplasmic domain. We conclude that survival pathways show previously unsuspected functional specialization for the acute and chronic phases of the stress response. Bcl-x(L) induction provides a "stop-gap" in acute stress, until slower but permanent pathways are activated. Furthermore, pathologic elevation of Bcl-x(L) may be the result of impaired adaptation, with implications for myeloproliferative disease mechanisms.
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21
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Mejia-Pous C, Damiola F, Gandrillon O. Cholesterol synthesis-related enzyme oxidosqualene cyclase is required to maintain self-renewal in primary erythroid progenitors. Cell Prolif 2011; 44:441-52. [PMID: 21951287 DOI: 10.1111/j.1365-2184.2011.00771.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
OBJECTIVES Molecular mechanisms controlling cell fate decision making in self-renewing cells are poorly understood. A previous transcriptomic study, carried out in primary avian erythroid progenitor cells (T2ECs), revealed that the gene encoding oxidosqualene cyclase (OSC/LSS), an enzyme involved in cholesterol biosynthesis, is significantly up-regulated in self-renewing cells. The aim of the present work is to understand whether this up-regulation is required for self-renewal maintenance and what are the mechanisms involved. MATERIALS AND METHODS To investigate OSC function, we studied effects of its enzymatic activity inhibition using Ro48-8071, a specific OSC inhibitor. In addition, we completed this pharmacological approach by RNAi-mediated OSC/LSS knockdown. The study of OSC inhibition was carried out on both self-renewing and differentiating cells to observe any state-dependent effect. RESULTS Our data show that OSC acts both by protecting self-renewing T2EC cells from apoptosis and by blocking their differentiation program, as OSC inhibition is sufficient to trigger spontaneous commitment of self-renewing cells towards an early differentiation state. This is self-renewal specific, as OSC inhibition has no effect on erythroid progenitors that have already differentiated. CONCLUSIONS Taken together, our results suggest that OSC/LSS expression and activity are required to maintain cell self-renewal and may be involved in the self-renewal versus differentiation/apoptosis decision making, by keeping cells in a self-renewal state.
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Affiliation(s)
- C Mejia-Pous
- Bases Moléculaires de l'Autorenouvellement et de ses Altérations" Group, Université de Lyon, Université Lyon 1, Villeurbanne, Centre de Génétique Moléculaire et Cellulaire, Lyon, France
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22
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From stem cell to red cell: regulation of erythropoiesis at multiple levels by multiple proteins, RNAs, and chromatin modifications. Blood 2011; 118:6258-68. [PMID: 21998215 DOI: 10.1182/blood-2011-07-356006] [Citation(s) in RCA: 308] [Impact Index Per Article: 23.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
This article reviews the regulation of production of RBCs at several levels. We focus on the regulated expansion of burst-forming unit-erythroid erythroid progenitors by glucocorticoids and other factors that occur during chronic anemia, inflammation, and other conditions of stress. We also highlight the rapid production of RBCs by the coordinated regulation of terminal proliferation and differentiation of committed erythroid colony-forming unit-erythroid progenitors by external signals, such as erythropoietin and adhesion to a fibronectin matrix. We discuss the complex intracellular networks of coordinated gene regulation by transcription factors, chromatin modifiers, and miRNAs that regulate the different stages of erythropoiesis.
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23
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Maragno AL, Pironin M, Alcalde H, Cong X, Knobeloch KP, Tangy F, Zhang DE, Ghysdael J, Quang CT. ISG15 modulates development of the erythroid lineage. PLoS One 2011; 6:e26068. [PMID: 22022510 PMCID: PMC3192153 DOI: 10.1371/journal.pone.0026068] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2011] [Accepted: 09/19/2011] [Indexed: 11/24/2022] Open
Abstract
Activation of erythropoietin receptor allows erythroblasts to generate erythrocytes. In a search for genes that are up-regulated during this differentiation process, we have identified ISG15 as being induced during late erythroid differentiation. ISG15 belongs to the ubiquitin-like protein family and is covalently linked to target proteins by the enzymes of the ISGylation machinery. Using both in vivo and in vitro differentiating erythroblasts, we show that expression of ISG15 as well as the ISGylation process related enzymes Ube1L, UbcM8 and Herc6 are induced during erythroid differentiation. Loss of ISG15 in mice results in decreased number of BFU-E/CFU-E in bone marrow, concomitant with an increased number of these cells in the spleen of these animals. ISG15(-/-) bone marrow and spleen-derived erythroblasts show a less differentiated phenotype both in vivo and in vitro, and over-expression of ISG15 in erythroblasts is found to facilitate erythroid differentiation. Furthermore, we have shown that important players of erythroid development, such as STAT5, Globin, PLC γ and ERK2 are ISGylated in erythroid cells. This establishes a new role for ISG15, besides its well-characterized anti-viral functions, during erythroid differentiation.
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Affiliation(s)
- Ana Leticia Maragno
- CNRS (Centre National de la Recherche Scientifique) UMR3306, Orsay, France
- INSERM (Institut National de la Santé et de la Recherche Médicale) U1005, Orsay, France
- Institut Curie, Centre Universitaire, Bat 110 91405, Orsay, France
| | - Martine Pironin
- CNRS (Centre National de la Recherche Scientifique) UMR3306, Orsay, France
- INSERM (Institut National de la Santé et de la Recherche Médicale) U1005, Orsay, France
- Institut Curie, Centre Universitaire, Bat 110 91405, Orsay, France
| | - Hélène Alcalde
- CNRS (Centre National de la Recherche Scientifique) UMR3306, Orsay, France
- INSERM (Institut National de la Santé et de la Recherche Médicale) U1005, Orsay, France
- Institut Curie, Centre Universitaire, Bat 110 91405, Orsay, France
| | - Xiuli Cong
- University of California San Diego, Moores University of California San Diego Cancer Center, La Jolla, California, United States of America
| | | | - Frederic Tangy
- Unité de Génomique Virale et Vaccination, CNRS URA-3015, Institut Pasteur, Paris, France
| | - Dong-Er Zhang
- University of California San Diego, Moores University of California San Diego Cancer Center, La Jolla, California, United States of America
| | - Jacques Ghysdael
- CNRS (Centre National de la Recherche Scientifique) UMR3306, Orsay, France
- INSERM (Institut National de la Santé et de la Recherche Médicale) U1005, Orsay, France
- Institut Curie, Centre Universitaire, Bat 110 91405, Orsay, France
| | - Christine Tran Quang
- CNRS (Centre National de la Recherche Scientifique) UMR3306, Orsay, France
- INSERM (Institut National de la Santé et de la Recherche Médicale) U1005, Orsay, France
- Institut Curie, Centre Universitaire, Bat 110 91405, Orsay, France
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Ripich T, Jessberger R. SWAP-70 regulates erythropoiesis by controlling α4 integrin. Haematologica 2011; 96:1743-52. [PMID: 21880631 DOI: 10.3324/haematol.2011.050468] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
UNLABELLED Background The regulation of normal and stress-induced erythropoiesis is incompletely understood. Integrin-dependent adhesion plays important roles in erythropoiesis, but how integrins are regulated during erythropoiesis remains largely unknown. DESIGN AND METHODS To obtain novel insights into the regulation of erythropoiesis, we used cellular and molecular approaches to analyze the role of SWAP-70 and the control of integrins through SWAP-70. In addition, mice deficient for this protein were investigated under normal and erythropoietic stress conditions. RESULTS We show that SWAP-70, a protein involved in cytoskeletal F-actin rearrangements and integrin regulation in mast cells, is expressed in hematopoietic stem cells and myeloid-erythroid precursors. Although Swap-70(-/-) mice are not anemic, erythroblastic differentiation is perturbed, and SWAP-70 is required for an efficient erythropoietic stress response to acute anemia and for erythropoietic recovery after bone marrow transplantation in irradiated mice. SWAP-70 deficiency impairs colony-forming unit erythroid development, while burst-forming unit erythroid development is normal, and significantly affects development of late erythroblasts in the spleen and bone marrow. The α(4) integrin is constitutively hyper-activated in Swap-70(-/-) colony-forming unit erythroid cells, which hyper-adhere to fibronectin. Blocking α(4) and β(1) integrin chains in vivo restored erythroblastic differentiation and the erythropoietic stress response in Swap-70(-/-) mice. Conclusions Our study reveals that SWAP-70 is a novel regulator of integrin-mediated red blood cell development and stress-induced erythropoiesis.
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Affiliation(s)
- Tatsiana Ripich
- Institute of Physiological Chemistry, Dresden University of Technology Fiedlerstr. 42, Dresden, Germany
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25
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Ineffective erythropoiesis with reduced red blood cell survival in serotonin-deficient mice. Proc Natl Acad Sci U S A 2011; 108:13141-6. [PMID: 21788492 DOI: 10.1073/pnas.1103964108] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Serotonin (5-HT) has long been recognized as a neurotransmitter in the central nervous system, where it modulates a variety of behavioral functions. Availability of 5-HT depends on the expression of the enzyme tryptophan hydroxylase (TPH), and the recent discovery of a dual system for 5-HT synthesis in the brain (TPH2) and periphery (TPH1) has renewed interest in studying the potential functions played by 5-HT in nonnervous tissues. Moreover, characterization of the TPH1 knockout mouse model (TPH1(-/-)) led to the identification of unsuspected roles for peripheral 5-HT, revealing the importance of this monoamine in regulating key physiological functions outside the brain. Here, we present in vivo data showing that mice deficient in peripheral 5-HT display morphological and cellular features of ineffective erythropoiesis. The central event occurs in the bone marrow where the absence of 5-HT hampers progression of erythroid precursors expressing 5-HT(2A) and 5-HT(2B) receptors toward terminal differentiation. In addition, red blood cells from 5-HT-deficient mice are more sensitive to macrophage phagocytosis and have a shortened in vivo half-life. The combination of these two defects causes TPH1(-/-) animals to develop a phenotype of macrocytic anemia. Direct evidence for a 5-HT effect on erythroid precursors is provided by supplementation of the culture medium with 5-HT that increases the proliferative capacity of both 5-HT-deficient and normal cells. Our thorough analysis of TPH1(-/-) mice provides a unique model of morphological and functional aberrations of erythropoiesis and identifies 5-HT as a key factor for red blood cell production and survival.
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Under HEMA conditions, self-replication of human erythroblasts is limited by autophagic death. Blood Cells Mol Dis 2011; 47:182-97. [PMID: 21775174 DOI: 10.1016/j.bcmd.2011.06.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2011] [Revised: 05/26/2011] [Accepted: 05/26/2011] [Indexed: 11/23/2022]
Abstract
The number of erythroblasts generated ex-vivo under human-erythroid massive-amplification conditions by mononuclear cells from one unit of adult blood (~10(10)) are insufficient for transfusion (~10(12) red cells), emphasizing the need for studies to characterize cellular interactions during culture to increase erythroblast production. To identify the cell populations which generate erythroblasts under human-erythroid-massive-amplification conditions and the factors that limit proliferation, day 10 non-erythroblasts and immature- and mature-erythroblasts were separated by sorting, labelled with carboxyfluorescein-diacetate-succinimidyl-ester and re-cultured either under these conditions (for proliferation, maturation and/or apoptosis/autophagy determinations) or in semisolid media (for progenitor cell determination). Non-erythroblasts contained 54% of the progenitor cells but did not grow under human-erythroid-massive-amplification conditions. Immature-erythroblasts contained 25% of the progenitor cells and generated erythroblasts under human-erythroid-massive-amplification conditions (FI at 48 h=2.57±1.15). Mature-erythroblasts did not generate colonies and died in human-erythroid-massive-amplification conditions. In sequential sorting/re-culture experiments, immature-erythroblasts retained the ability to generate erythroblasts for 6 days and generated 2-5-fold more cells than the corresponding unfractionated population, suggesting that mature-erythroblasts may limit erythroblast expansion. In co-cultures of carboxyfluorescein-diacetate-succinimidyl-ester-labelled-immature-erythroblasts with mature-erythroblasts at increasing ratios, cell numbers did not increase and proliferation, maturation and apoptotic rates were unchanged. However, Acridine Orange staining (a marker for autophagic death) increased from ~3.2% in cultures with immature-erythroblasts alone to 14-22% in cultures of mature-erythroblasts with and without immature-erythroblasts. In conclusion, these data identify immature-erythroblasts as the cells that generate additional erythroblasts in human-erythroid-massive-amplification cultures and autophagy as the leading cause of death limiting the final cellular output of these cultures.
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The dominant negative β isoform of the glucocorticoid receptor is uniquely expressed in erythroid cells expanded from polycythemia vera patients. Blood 2011; 118:425-36. [PMID: 21355091 DOI: 10.1182/blood-2010-07-296921] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Glucocorticoid receptor (GR) agonists increase erythropoiesis in vivo and in vitro. To clarify the effect of the dominant negative GRβ isoform (unable to bind STAT-5) on erythropoiesis, erythroblast (EB) expansion cultures of mononuclear cells from 18 healthy (nondiseased) donors (NDs) and 16 patients with polycythemia vera (PV) were studied. GRβ was expressed in all PV EBs but only in EBs from 1 ND. The A3669G polymorphism, which stabilizes GRβ mRNA, had greater frequency in PV (55%; n = 22; P = .0028) and myelofibrosis (35%; n = 20) patients than in NDs (9%; n = 22) or patients with essential thrombocythemia (6%; n = 15). Dexamethasone stimulation of ND cultures increased the number of immature EBs characterized by low GATA1 and β-globin expression, but PV cultures generated great numbers of immature EBs with low levels of GATA1 and β-globin irrespective of dexamethasone stimulation. In ND EBs, STAT-5 was not phosphorylated after dexamethasone and erythropoietin treatment and did not form transcriptionally active complexes with GRα, whereas in PV EBs, STAT-5 was constitutively phosphorylated, but the formation of GR/STAT-5 complexes was prevented by expression of GRβ. These data indicate that GRβ expression and the presence of A3669G likely contribute to development of erythrocytosis in PV and provide a potential target for identification of novel therapeutic agents.
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HIF1alpha synergizes with glucocorticoids to promote BFU-E progenitor self-renewal. Blood 2010; 117:3435-44. [PMID: 21177435 DOI: 10.1182/blood-2010-07-295550] [Citation(s) in RCA: 125] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
With the aim of finding small molecules that stimulate erythropoiesis earlier than erythropoietin and that enhance erythroid colony-forming unit (CFU-E) production, we studied the mechanism by which glucocorticoids increase CFU-E formation. Using erythroid burst-forming unit (BFU-E) and CFU-E progenitors purified by a new technique, we demonstrate that glucocorticoids stimulate the earliest (BFU-E) progenitors to undergo limited self-renewal, which increases formation of CFU-E cells > 20-fold. Interestingly, glucocorticoids induce expression of genes in BFU-E cells that contain promoter regions highly enriched for hypoxia-induced factor 1α (HIF1α) binding sites. This suggests activation of HIF1α may enhance or replace the effect of glucocorticoids on BFU-E self-renewal. Indeed, HIF1α activation by a prolyl hydroxylase inhibitor (PHI) synergizes with glucocorticoids and enhances production of CFU-Es 170-fold. Because PHIs are able to increase erythroblast production at very low concentrations of glucocorticoids, PHI-induced stimulation of BFU-E progenitors thus represents a conceptually new therapeutic window for treating erythropoietin-resistant anemia.
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29
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Immature erythroblasts with extensive ex vivo self-renewal capacity emerge from the early mammalian fetus. Blood 2010; 117:2708-17. [PMID: 21127173 DOI: 10.1182/blood-2010-07-299743] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In the hematopoietic hierarchy, only stem cells are thought to be capable of long-term self-renewal. Erythroid progenitors derived from fetal or adult mammalian hematopoietic tissues are capable of short-term, or restricted (10(2)- to 10(5)-fold), ex vivo expansion in the presence of erythropoietin, stem cell factor, and dexamethasone. Here, we report that primary erythroid precursors derived from early mouse embryos are capable of extensive (10(6)- to 10(60)-fold) ex vivo proliferation. These cells morphologically, immunophenotypically, and functionally resemble proerythroblasts, maintaining both cytokine dependence and the potential, despite prolonged culture, to generate enucleated erythrocytes after 3-4 maturational cell divisions. This capacity for extensive erythroblast self-renewal is temporally associated with the emergence of definitive erythropoiesis in the yolk sac and its transition to the fetal liver. In contrast, hematopoietic stem cell-derived definitive erythropoiesis in the adult is associated almost exclusively with restricted ex vivo self-renewal. Primary primitive erythroid precursors, which lack significant expression of Kit and glucocorticoid receptors, lack ex vivo self-renewal capacity. Extensively self-renewing erythroblasts, despite their near complete maturity within the hematopoietic hierarchy, may ultimately serve as a renewable source of red cells for transfusion therapy.
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30
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Ferbeyre G, Moriggl R. The role of Stat5 transcription factors as tumor suppressors or oncogenes. Biochim Biophys Acta Rev Cancer 2010; 1815:104-14. [PMID: 20969928 DOI: 10.1016/j.bbcan.2010.10.004] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2010] [Revised: 10/08/2010] [Accepted: 10/08/2010] [Indexed: 02/06/2023]
Abstract
Stat5 is constitutively activated in many human cancers affecting the expression of cell proliferation and cell survival controlling genes. These oncogenic functions of Stat5 have been elegantly reproduced in mouse models. Aberrant Stat5 activity induces also mitochondrial dysfunction and reactive oxygen species leading to DNA damage. Although DNA damage can stimulate tumorigenesis, it can also prevent it. Stat5 can inhibit tumor progression like in the liver and it is a tumor suppressor in fibroblasts. Stat5 proteins are able to regulate cell differentiation and senescence activating the tumor suppressors SOCS1, p53 and PML. Understanding the context dependent regulation of tumorigenesis through Stat5 function will be central to understand proliferation, survival, differentiation or senescence of cancer cells.
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Affiliation(s)
- G Ferbeyre
- Département de Biochimie, Université de Montréal, Montréal, Québec H3C 3J7, Canada.
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31
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Gardenghi S, Grady RW, Rivella S. Anemia, ineffective erythropoiesis, and hepcidin: interacting factors in abnormal iron metabolism leading to iron overload in β-thalassemia. Hematol Oncol Clin North Am 2010; 24:1089-107. [PMID: 21075282 DOI: 10.1016/j.hoc.2010.08.003] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
β-Thalassemia is a genetic disorder caused by mutations in the β-globin gene and characterized by chronic anemia caused by ineffective erythropoiesis, and accompanied by a variety of serious secondary complications such as extramedullary hematopoiesis, splenomegaly, and iron overload. In the past few years, numerous studies have shown that such secondary disease conditions have a genetic basis caused by the abnormal expression of genes with a role in controlling erythropoiesis and iron metabolism. In this article, the most recent discoveries related to the mechanism(s) responsible for anemia/ineffective erythropoiesis and iron overload are discussed in detail. Particular attention is paid to the pathway(s) controlling the expression of hepcidin, which is the main regulator of iron metabolism, and the Epo/EpoR/Jak2/Stat5 signaling pathway, which regulates erythropoiesis. Better understanding of how these pathways function and are altered in β-thalassemia has revealed several possibilities for development of new therapeutic approaches to treat of the complications of this disease.
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Affiliation(s)
- Sara Gardenghi
- Hematology-Oncology, Department of Pediatrics, Weill Cornell Medical College, 515 East 71st Street, New York, NY 10021, USA
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32
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Lodish H, Flygare J, Chou S. From stem cell to erythroblast: regulation of red cell production at multiple levels by multiple hormones. IUBMB Life 2010; 62:492-6. [PMID: 20306512 DOI: 10.1002/iub.322] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
This article reviews the regulation of production of red blood cells at several levels: (1) the ability of erythropoietin and adhesion to a fibronectin matrix to stimulate the rapid production of red cells by inducing terminal proliferation and differentiation of committed erythroid CFU-E progenitors; (2) the regulated expansion of the pool of earlier BFU-E erythroid progenitors by glucocorticoids and other factors that occurs during chronic anemia or inflammation; and (3) the expansion of thehematopoietic cell pool to produce more progenitors of all hematopoietic lineages.
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Affiliation(s)
- Harvey Lodish
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA.
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33
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Pradet-Balade B, Leberbauer C, Schweifer N, Boulmé F. Massive translational repression of gene expression during mouse erythroid differentiation. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2010; 1799:630-41. [PMID: 20804875 DOI: 10.1016/j.bbagrm.2010.08.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2010] [Revised: 08/06/2010] [Accepted: 08/18/2010] [Indexed: 12/15/2022]
Abstract
We took advantage of a mouse erythroid differentiation system to determine the relative contribution of transcriptional and translational control during this process. Comparison of expression data obtained with total cytoplasmic mRNAs or polysome-bound mRNAs (actively translated mRNAs) on Affymetrix high-density oligonucleotide microarrays revealed different characteristics of the two regulatory mechanisms. Indeed, mRNA expression from a vast majority of genes was affected, albeit most changes were relatively small and occurred at a low pace. Translational control, however, affected a smaller fraction of genes but was effective at earlier time-points. This analysis unravels six clusters of genes showing no significant variation in mRNA expression levels whereas they are submitted to translational regulation. Their involvement in terminal mouse erythropoiesis may prove to be highly relevant. Furthermore, the data from specific and functional categories of genes emphasize that translational control, not only reinforces the transcriptional effect, but allows the cell to increase the complexity in gene expression regulation patterns.
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Affiliation(s)
- Bérengère Pradet-Balade
- Department of Immunology and Oncology, Centro Nacional de Biotecnologia CNB-CSIC, Campus de Cantoblanco, Madrid, Spain
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Stellacci E, Di Noia A, Di Baldassarre A, Migliaccio G, Battistini A, Migliaccio AR. Interaction between the glucocorticoid and erythropoietin receptors in human erythroid cells. Exp Hematol 2009; 37:559-72. [PMID: 19375647 DOI: 10.1016/j.exphem.2009.02.005] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2008] [Revised: 02/02/2009] [Accepted: 02/04/2009] [Indexed: 01/08/2023]
Abstract
OBJECTIVE The aim of this study was to identify whether the rapid membrane-associated pathway of the glucocorticoid receptor (GR) is active in erythroid cells and plays any role in determining the reversible inhibition on erythroid maturation exerted by GR. MATERIALS AND METHODS First we determined the biological effects (inhibition of apoptosis and induction of beta-globin expression) induced in primary erythroblasts by erythropoietin (EPO) and the GR agonist dexamethasone (DXM), alone and in combination. Next, by biochemical analysis, we determined the association between GR and EPO receptor in proerythroblasts generated in vitro from 10 normal adult donors. These studies also analyzed the levels of signal transducers and activators of transcription-5 (STAT-5) phosphorylation induced when the cells were stimulated with DXM alone or in combination with EPO. RESULTS DXM antagonized the beta-globin messenger RNA increases, but not the inhibition of apoptosis induced by EPO in primary cells. DXM also antagonized the ability of EPO to induce STAT-5 phosphorylation in these cells. In fact, EPO and DXM alone, but not in combination, induced phosphorylation and nuclear translocation of STAT-5. The inhibition likely occurred through an interaction between the two receptors because GR became associated with the EPO receptor and STAT-5 in cells stimulated with EPO and DXM. CONCLUSION These data suggest that glucocorticoids inhibit erythroid maturation not only through a transcriptional mechanism, but also through a rapid membrane-associated pathway that interferes with EPO receptor signaling.
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Affiliation(s)
- Emilia Stellacci
- Department of Infectious, Parasitic and Immunomediated Diseases, University of Chieti-Pescara, Chieti, Italy
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Abstract
Erythropoiesis strictly depends on signal transduction through the erythropoietin receptor (EpoR)-Janus kinase 2 (Jak2)-signal transducer and activator of transcription 5 (Stat5) axis, regulating proliferation, differentiation, and survival. The exact role of the transcription factor Stat5 in erythropoiesis remained puzzling, however, since the first Stat5-deficient mice carried a hypomorphic Stat5 allele, impeding full phenotypical analysis. Using mice completely lacking Stat5--displaying early lethality--we demonstrate that these animals suffer from microcytic anemia due to reduced expression of the antiapoptotic proteins Bcl-x(L) and Mcl-1 followed by enhanced apoptosis. Moreover, transferrin receptor-1 (TfR-1) cell surface levels on erythroid cells were decreased more than 2-fold on erythroid cells of Stat5(-/-) animals. This reduction could be attributed to reduced transcription of TfR-1 mRNA and iron regulatory protein 2 (IRP-2), the major translational regulator of TfR-1 mRNA stability in erythroid cells. Both genes were demonstrated to be direct transcriptional targets of Stat5. This establishes an unexpected mechanistic link between EpoR/Jak/Stat signaling and iron metabolism, processes absolutely essential for erythropoiesis and life.
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Abstract
Signal transducer and activator of transcription (STAT)5A and -5B are latent transcription factors activated by cytokines and hormones of the cytokine family. In pancreatic insulin-secreting β-cells, STAT5A and -5B are activated primarily by prolactin and growth hormone stimulation and are important mediators of the potent stimulation of proliferation and insulin production caused by these hormones. STAT5A and -5B are both expressed in β-cells and control the expression of a number of mRNAs implicated in cell replication control, insulin biosynthesis and secretion. In addition to STAT5A and -5B being transcriptional activators, they may also repress gene transcription. By these means, STAT5 proteins increase the levels of anti-apoptotic transcripts in β-cells and repress expression of pro-apoptotic genes. This review focuses on the anti-apoptotic role of STAT5 signaling, providing a mechanism for β-cell resistance to pro-apoptotic cytokines, Type 1 diabetes mellitus and obesity-associated β-cell stress. It is clear from studies of STAT5 signaling in pancreatic β-cells that STAT5 is important for postnatal β-cell compensatory growth (as in pregnancy or obesity) and in the defense against β-cell stress factors.
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Affiliation(s)
- Louise T Dalgaard
- a Roskilde University, Department of Science, Universitetsvej 1, DK-4000 Roskilde, Denmark.
| | - Nils Billestrup
- b Steno Diabetes Center, Niels Steensens Vej 2, DK-2820 Gentofte, Denmark.
| | - Jens H Nielsen
- c University of Copenhagen, Department of Biomedical Research, Panum Institute, Bldg 6.5, Blegdamsvej 3C, DK-2200 Copenhagen N, Denmark.
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Decreased differentiation of erythroid cells exacerbates ineffective erythropoiesis in beta-thalassemia. Blood 2008; 112:875-85. [PMID: 18480424 DOI: 10.1182/blood-2007-12-126938] [Citation(s) in RCA: 129] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
In beta-thalassemia, the mechanism driving ineffective erythropoiesis (IE) is insufficiently understood. We analyzed mice affected by beta-thalassemia and observed, unexpectedly, a relatively small increase in apoptosis of their erythroid cells compared with healthy mice. Therefore, we sought to determine whether IE could also be characterized by limited erythroid cell differentiation. In thalassemic mice, we observed that a greater than normal percentage of erythroid cells was in S-phase, exhibiting an erythroblast-like morphology. Thalassemic cells were associated with expression of cell cycle-promoting genes such as EpoR, Jak2, Cyclin-A, Cdk2, and Ki-67 and the antiapoptotic protein Bcl-X(L). The cells also differentiated less than normal erythroid ones in vitro. To investigate whether Jak2 could be responsible for the limited cell differentiation, we administered a Jak2 inhibitor, TG101209, to healthy and thalassemic mice. Exposure to TG101209 dramatically decreased the spleen size but also affected anemia. Although our data do not exclude a role for apoptosis in IE, we propose that expansion of the erythroid pool followed by limited cell differentiation exacerbates IE in thalassemia. In addition, these results suggest that use of Jak2 inhibitors has the potential to profoundly change the management of this disorder.
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Abstract
Erythropoiesis requires erythropoietin (Epo) and stem cell factor (SCF) signaling via their receptors EpoR and c-Kit. EpoR, like many other receptors involved in hematopoiesis, acts via the kinase Jak2. Deletion of EpoR or Janus kinase 2 (Jak2) causes embryonic lethality as a result of defective erythropoiesis. The contribution of distinct EpoR/Jak2-induced signaling pathways (mitogen-activated protein kinase, phosphatidylinositol 3-kinase, signal transducer and activator of transcription 5 [Stat5]) to functional erythropoiesis is incompletely understood. Here we demonstrate that expression of a constitutively activated Stat5a mutant (cS5) was sufficient to relieve the proliferation defect of Jak2(-/-) and EpoR(-/-) cells in an Epo-independent manner. In addition, tamoxifen-induced DNA binding of a Stat5a-estrogen receptor (ER)* fusion construct enabled erythropoiesis in the absence of Epo. Furthermore, c-Kit was able to enhance signaling through the Jak2-Stat5 axis, particularly in lymphoid and myeloid progenitors. Although abundance of hematopoietic stem cells was 2.5-fold reduced in Jak2(-/-) fetal livers, transplantation of Jak2(-/-)-cS5 fetal liver cells into irradiated mice gave rise to mature erythroid and myeloid cells of donor origin up to 6 months after transplantation. Cytokine- and c-Kit pathways do not function independently of each other in hematopoiesis but cooperate to attain full Jak2/Stat5 activation. In conclusion, activated Stat5 is a critical downstream effector of Jak2 in erythropoiesis/myelopoiesis, and Jak2 functionally links cytokine- with c-Kit-receptor tyrosine kinase signaling.
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STAT5 requires the N-domain to maintain hematopoietic stem cell repopulating function and appropriate lymphoid-myeloid lineage output. Exp Hematol 2008; 35:1684-94. [PMID: 17976521 DOI: 10.1016/j.exphem.2007.08.026] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2007] [Revised: 08/20/2007] [Accepted: 08/20/2007] [Indexed: 11/22/2022]
Abstract
OBJECTIVE Signal transducer and activator of transcription 5 (STAT5) is a critical regulator of hematopoietic development and its impaired activation is associated with hematopoietic and immune cell defects. However, much of this information has been learned from knockout mice that still retain the potential for expression of STAT5 proteins that are N-terminally truncated due to alternative internal translation initiation codons. The goal of these studies was to use transplantation-based assays to analyze the degree of STAT5 deltaN activity in hematopoietic stem cells (HSC) and throughout lymphomyeloid development. METHODS We have directly compared E14.5 fetal liver cells from mice with potential to express STAT5ab deltaN (STAT5ab(deltaN/deltaN)) with mice completely lacking STAT5a and STAT5b (STAT5abnull/null). We have also utilized retroviral complementation of STAT5abnull/null fetal liver HSC to enforce expression of full-length STAT5a or STAT5a lacking the first 136 amino acids (STAT5a deltaN). RESULTS We report that STAT5 is required for HSC, lymphocyte, and erythrocyte development. We demonstrate that restored expression of STAT5a in STAT5abnull/null HSC provides a strong selective advantage, correcting T- and B-lymphocyte and erythrocyte development. Interestingly, Gr-1(+) blood cells were inversely correlated with B lymphocytes and both were normalized by STAT5a expression. In contrast, transduction of STAT5a deltaN only provided partial B-lymphocyte development. CONCLUSIONS These studies define the role of STAT5 in maintaining normal lymphoid vs myeloid balance during hematopoiesis and highlight a major role for the N-domain in HSC function. The platform of retroviral complementation described here will be particularly useful for future studies to subdefine the N-domain regions that are critical for hematopoiesis.
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Castellanos A, Lang G, Frampton J, Weston K. Regulation of erythropoiesis by the neuronal transmembrane protein Lrfn2. Exp Hematol 2007; 35:724-34. [PMID: 17577922 DOI: 10.1016/j.exphem.2007.02.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
OBJECTIVE The transgenic mouse line MEnTCD2.5 expresses a dominant interfering Myb protein in a T-cell-specific fashion. When MEnTCD2.5 animals are crossed to a second line ubiquitously expressing Myc, they develop a rapid onset, fatal disease characterized by enlarged lymph nodes full of nonlymphoid cells. This study aimed to elucidate the reason for this anomalous non-T-cell phenotype. MATERIALS AND METHODS We studied the cells by morphological analysis, surface marker staining, mRNA expression studies and in vitro colony-forming assays. RESULTS Aberrant cells in MEnTCD2.5 lymph nodes are erythroblasts, and cooperation between MEnTCD2.5 and Myc causes severe erythroblastosis, but not erythroleukemia. MEnTCD2.5:Myc and MEnTCD2.5 animals have pronounced extramedullary erythropoiesis in their lymph nodes, and some increase in bone marrow-derived erythroid progenitors; no other MEnTCD2 transgenic line cooperates in this fashion with Myc, suggesting that the MEnTCD2.5 integration site, in intron 2 of the Lrfn2 gene, is of importance. To confirm this, in in vitro colony-forming assays, expression of wild-type Lrfn2 phenocopies the MEnTCD2.5 defect. Finally, Lrfn2 expression also causes the outgrowth of a bizarre cell type in colony-forming assays that stains positively for both early hematopoietic and fibroblast/fibrocyte surface markers. CONCLUSIONS The Lrfn2 protein, a transmembrane adhesion-type molecule, is able to subvert hematopoietic differentiation to increase erythropoiesis. In cooperation with Myc, this leads to erythroblastosis. Lrfn2 may also be involved in colony forming units-fibroblast regulation. As Lrfn2 expression is detectable in wild-type bone marrow, it likely plays a novel role during normal hematopoiesis.
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Affiliation(s)
- Andres Castellanos
- Institute of Cancer Research, CR-UK Centre for Cell and Molecular Biology, London, UK
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Schepers H, van Gosliga D, Wierenga ATJ, Eggen BJL, Schuringa JJ, Vellenga E. STAT5 is required for long-term maintenance of normal and leukemic human stem/progenitor cells. Blood 2007; 110:2880-8. [PMID: 17630355 DOI: 10.1182/blood-2006-08-039073] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Abstract
The transcription factor STAT5 fulfills a distinct role in the hematopoietic system, but its precise role in primitive human hematopoietic cells remains to be elucidated. Therefore, we performed STAT5 RNAi in sorted cord blood (CB) and acute myeloid leukemia (AML) CD34+ cells by lentiviral transduction and investigated effects of STAT5 downmodulation on the normal stem/progenitor cell compartment and the leukemic counterpart. STAT5 RNAi cells displayed growth impairment, without affecting their differentiation in CB and AML cultures on MS5 stroma. In CB, limiting-dilution assays demonstrated a 3.9-fold reduction in progenitor numbers. Stem cells were enumerated in long-term culture-initiating cell (LTC-IC) assays, and the average LTC-IC frequency was 3.25-fold reduced from 0.13% to 0.04% by STAT5 down-regulation. Single-cell sorting experiments of CB CD34+/CD38− cells demonstrated a 2-fold reduced cytokine-driven expansion, with a subsequent 2.3-fold reduction of progenitors. In sorted CD34+ AML cells with constitutive STAT5 phosphorylation (5/8), STAT5 RNAi demonstrated a reduction in cell number (72% ± 17%) and a decreased expansion (17 ± 15 vs 80 ± 58 in control cultures) at week 6 on MS5 stroma. Together, our data indicate that STAT5 expression is required for the maintenance and expansion of primitive hematopoietic stem and progenitor cells, both in normal as well as leukemic hematopoiesis.
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Affiliation(s)
- Hein Schepers
- Division of Hematology, Department of Medicine, University Medical Center Groningen, Groningen, the Netherlands
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Föller M, Kasinathan RS, Koka S, Huber SM, Schuler B, Vogel J, Gassmann M, Lang F. Enhanced susceptibility to suicidal death of erythrocytes from transgenic mice overexpressing erythropoietin. Am J Physiol Regul Integr Comp Physiol 2007; 293:R1127-34. [PMID: 17567717 DOI: 10.1152/ajpregu.00110.2007] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Eryptosis, a suicidal death of mature erythrocytes, is characterized by decrease of cell volume, cell membrane blebbing, and breakdown of cell membrane asymmetry with phosphatidylserine exposure at the cell surface. Triggers of eryptosis include increased cytosolic Ca(2+) activity, which could result from activation of Ca(2+)-permeable cation channels. Ca(2+) triggers phosphatidylserine exposure and activates Ca(2+)-sensitive K(+) channels, leading to cellular K(+) loss and cell shrinkage. The cation channels and thus eryptosis are stimulated by Cl(-) removal and inhibited by erythropoietin. The present experiments explored eryptosis in transgenic mice overexpressing erythropoietin (tg6). Erythrocytes were drawn from tg6 mice and their wild-type littermates (WT). Phosphatidylserine exposure was estimated from annexin binding and cell volume from forward scatter in fluorescence-activated cell sorting (FACS) analysis. The percentage of annexin binding was significantly larger and forward scatter significantly smaller in tg6 than in WT erythrocytes. Transgenic erythrocytes were significantly more resistant to osmotic lysis than WT erythrocytes. Cl(-) removal and exposure to the Ca(2+) ionophore ionomycin (1 microM) increased annexin binding and decreased forward scatter, effects larger in tg6 than in WT erythrocytes. The K(+) ionophore valinomycin (10 nM) triggered eryptosis in both tg6 and WT erythrocytes and abrogated differences between genotypes. An increase of extracellular K(+) concentration to 125 mM blunted the difference between tg6 and WT erythrocytes. Fluo-3 fluorescence reflecting cytosolic Ca(2+) activity was larger in tg6 than in WT erythrocytes. In conclusion, circulating erythrocytes from tg6 mice are sensitized to triggers of eryptosis but more resistant to osmotic lysis, properties at least partially due to enhanced Ca(2+) entry and increased K(+) channel activity.
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Affiliation(s)
- Michael Föller
- Physiologisches Institut, der Universität Tübingen, Gmelinstrasse 5, D 72076 Tübingen, Germany
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Abstract
PURPOSE OF REVIEW In addition to its essential role in baseline erythropoiesis, the hormone erythropoietin drives the erythropoietic response to hypoxic stress. A mechanistic understanding of stress erythropoiesis would benefit multiple clinical settings, and may aid in understanding leukemogenesis. RECENT FINDINGS The spectrum of progenitors targeted by the erythropoietin receptor is broader during stress than during baseline erythropoiesis. Further, the requirement for erythropoietin receptor signaling is more stringent during stress. However, erythropoietin receptor signaling has been mostly studied in vitro, where it is difficult to relate signaling events to stress-dependent changes in erythroid homeostasis. Here we review advances in flow cytometry that allow the identification and study of murine erythroid precursors in hematopoietic tissue as they are responding to stress in vivo. The death receptor Fas and its ligand, FasL, are coexpressed by early splenic erythroblasts, suppressing erythroblast survival and erythropoietic rate. During stress, erythropoietin receptor signaling downregulates erythroblast Fas and FasL, consequently increasing erythropoietic rate. SUMMARY Erythropoietic rate is regulated at least in part through the erythropoietin receptor-mediated survival of splenic early erythroblasts. Future research will delineate how multiple antiapoptotic pathways, potentially activated by the erythropoietin receptor, interact to produce the remarkable dynamic range of erythropoiesis.
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Affiliation(s)
- Merav Socolovsky
- Department of Pediatrics, University of Massachusetts Medical School, Worcester, MA 01605, USA.
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Desrivières S, Kunz C, Barash I, Vafaizadeh V, Borghouts C, Groner B. The biological functions of the versatile transcription factors STAT3 and STAT5 and new strategies for their targeted inhibition. J Mammary Gland Biol Neoplasia 2006; 11:75-87. [PMID: 16947086 DOI: 10.1007/s10911-006-9014-4] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
Abstract
Signal transducers and activators of transcription (STATs) comprise a unique family of transcription factors, which transmit the interactions of cytokines, hormones and growth factors with their cell surface receptors into transcriptional programs. The mechanism of STAT activation has been well-established and comprises tyrosine phosphorylation, dimerization, nuclear translocation, binding to specific DNA response elements, recruitment of co-activators or co-repressors and transcriptional induction or repression of target genes. Gene deletion, microarrays, proteomics and chromatin immunoprecipitation experiments have revealed target genes with a broad range of functions regulated by STAT3 and STAT5. In the mammary gland, STAT5-induced genes contribute mainly to the prolactin dependent lobulo-alveolar development, whereas STAT3 induced genes control apoptosis during involution. Crucial effects have also been observed in other tissues. The germ line deletion of STAT3 or STAT5 causes early embryonal or perinatal lethality in mice. STAT5 is also required for proliferation of T- and B-cells and hematopoietic stem cell self-renewal. Deregulated STAT activity is often found associated with tumorigenesis and activated STATs seem to be limiting components in tumor cells. This review summarizes the functions of STAT3 and STAT5 in different cell types and the strategies that are used to counteract their action in tumor cells.
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Affiliation(s)
- Sylvane Desrivières
- Georg-Speyer-Haus, Institute for Biomedical Research, Paul-Ehrlich-Strasse 42, D-60596 Frankfurt am Main, Germany
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