33 results on '"Rivella, Stefano"'
Search Results
2. Contributors
- Author
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Angelos, Mathew G., primary, Baglieri, Jacopo, additional, Bertoni, Carmen, additional, Breda, Laura, additional, Büning, Hildegard, additional, Chan, Lawrence, additional, Chen, Wenhao, additional, Cooper, Laurence J.N., additional, Dong, Alisa, additional, Evans, Christopher H., additional, Gersbach, Charles A., additional, Ghivizzani, Steven C., additional, Gill, Saar, additional, Glorioso, Joseph C., additional, Goins, William F., additional, Hackett, Perry B., additional, Hammond, H. Kirk, additional, Jain, Manu, additional, Kalos, Michael, additional, Kaufman, Dan S., additional, Kidwai, Fahad, additional, Kontos, Christopher D., additional, Kratzke, Robert A., additional, MacLaren, Robert E., additional, McClements, Michelle E., additional, Mingozzi, Federico, additional, Mueller, Sarah B., additional, Ning, Jianfang, additional, Patel, Manish R., additional, Prickett, Michelle, additional, Rabkin, Samuel D., additional, Rivella, Stefano, additional, Robbins, Paul D., additional, Simonato, Michele, additional, Starr, Timothy K., additional, Tang, Tong, additional, Thakore, Pratiksha I., additional, Tolar, Jakub, additional, Wahlberg, Lars U., additional, Walsh, Christopher E., additional, Wu, Jie, additional, Xie, Aini, additional, and Yang, Yisheng, additional
- Published
- 2015
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3. Use of HSC Targeted LNP to Generate a Mouse Model of Lethal α-Thalassemia and Treatment via Lentiviral Gene Therapy.
- Author
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Chappell ME, Breda L, Tricoli L, Guerra A, Jarocha DJ, Castruccio Castracani C, Papp TE, Tanaka N, Hamilton N, Triebwasser MP, Ghiaccio V, Fedorky M, Gollomp K, Bochenek V, Roche AM, Everett JK, Cook EJ, Bushman FD, Teawtrakul N, Glentis S, Kattamis A Prof, Mui BL, Tam YK, Weissman D, Abdulmalik O, Parhiz H, and Rivella S
- Abstract
-Thalassemia (AT) is one of the most commonly occurring inherited hematological diseases. However, few treatments are available, and allogeneic bone marrow transplantation (BMT) is the only available therapeutic option for patients with severe AT. Research into AT has remained limited due to a lack of adult mouse models, with severe AT typically resulting in in utero lethality. By using a lipid nanoparticle (LNP) targeting the receptor CD117 and delivering a Cre mRNA (mRNACreLNPCD117), we were able to delete floxed -globin genes at high efficiency in hematopoietic stem cells (HSC) ex vivo. These cells were then engrafted in the absence or presence of a novel α-globin expressing lentiviral vector (ALS20I). Myeloablated mice transplanted with mRNACreLNPCD117-treated HSC showed a complete knockout of -globin genes. They demonstrated a phenotype characterized by the synthesis of hemoglobin H (-tetramers, or HbH), aberrant erythropoiesis, and abnormal organ morphology, culminating in lethality approximately eight weeks following engraftment. Mice receiving mRNACreLNPCD117-treated HSC with at least one copy of ALS20I survived long-term with normalization of erythropoiesis, decreased the production of HbH, and ameliorated the abnormal organ morphology. Furthermore, we tested ALS20I in erythroid progenitors derived from -globin-KO CD34+ and cells isolated from patients with both deletional and non-deletional HbH disease, demonstrating improvement in -globin/-globin mRNA ratio and reduction in the formation of HbH by HPLC. Our results demonstrate the broad applicability of LNP for disease modeling, characterization of a novel severe mouse model of AT, and the efficacy of ALS20I for treating AT., (Copyright © 2024 American Society of Hematology.)
- Published
- 2024
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4. Carbonyl iron and iron dextran therapies cause adverse effects on bone health in juveniles with chronic kidney disease.
- Author
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Patino E, Doty SB, Bhatia D, Meza K, Zhu YS, Rivella S, Choi ME, and Akchurin O
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- Animals, Bone Density, Fibroblast Growth Factor-23, Glomerular Filtration Rate, Iron, Mice, Dextrans, Renal Insufficiency, Chronic complications, Renal Insufficiency, Chronic drug therapy
- Abstract
Anemia is a frequent complication of chronic kidney disease (CKD), related in part to the disruption of iron metabolism. Iron therapy is very common in children with CKD and excess iron has been shown to induce bone loss in non-CKD settings, but the impact of iron on bone health in CKD remains poorly understood. Here, we evaluated the effect of oral and parenteral iron therapy on bone transcriptome, bone histology and morphometry in two mouse models of juvenile CKD (adenine-induced and 5/6-nephrectomy). Both modalities of iron therapy effectively improved anemia in the mice with CKD, and lowered bone Fgf23 expression. At the same time, iron therapy suppressed genes implicated in bone formation and resulted in the loss of cortical and trabecular bone in the mice with CKD. Bone resorption was activated in untreated CKD, but iron therapy had no additional effect on this. Furthermore, we assessed the relationship between biomarkers of bone turnover and iron status in a cohort of children with CKD. Children treated with iron had lower levels of circulating biomarkers of bone formation (bone-specific alkaline phosphatase and the amino-terminal propeptide of type 1 procollagen), as well as fewer circulating osteoblast precursors, compared to children not treated with iron. These differences were independent of age, sex, and glomerular filtration rate. Thus, iron therapy adversely affected bone health in juvenile mice with CKD and was associated with low levels of bone formation biomarkers in children with CKD., (Copyright © 2020 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.)
- Published
- 2020
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5. Correcting β-thalassemia by combined therapies that restrict iron and modulate erythropoietin activity.
- Author
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Casu C, Pettinato M, Liu A, Aghajan M, Lo Presti V, Lidonnici MR, Munoz KA, O'Hara E, Olivari V, Di Modica SM, Booten S, Guo S, Neil G, Miari R, Shapir N, Zafir-Lavie I, Domev H, Ferrari G, Sitara D, Nai A, and Rivella S
- Subjects
- Animals, Cells, Cultured, Erythropoiesis drug effects, Erythropoiesis genetics, Gene Expression Regulation drug effects, Iron metabolism, Iron Overload genetics, Iron Overload prevention & control, Male, Membrane Proteins genetics, Membrane Proteins metabolism, Mice, Mice, Inbred C57BL, Mice, Transgenic, Oligonucleotides, Antisense pharmacology, Receptors, Transferrin genetics, Serine Endopeptidases genetics, Serine Endopeptidases metabolism, beta-Thalassemia metabolism, Erythropoietin administration & dosage, Erythropoietin genetics, Genetic Therapy methods, Membrane Proteins antagonists & inhibitors, Oligonucleotides, Antisense administration & dosage, beta-Thalassemia therapy
- Abstract
β-Thalassemia intermedia is a disorder characterized by ineffective erythropoiesis (IE), anemia, splenomegaly, and systemic iron overload. Novel approaches are being explored based on the modulation of pathways that reduce iron absorption (ie, using hepcidin activators like Tmprss6-antisense oligonucleotides [ASOs]) or increase erythropoiesis (by erythropoietin [EPO] administration or modulating the ability of transferrin receptor 2 [Tfr2] to control red blood cell [RBC] synthesis). Targeting Tmprss6 messenger RNA by Tmprss6-ASO was proven to be effective in improving IE and splenomegaly by inducing iron restriction. However, we postulated that combinatorial strategies might be superior to single therapies. Here, we combined Tmprss6-ASO with EPO administration or removal of a single Tfr2 allele in the bone marrow of animals affected by β-thalassemia intermedia (Hbbth3/+). EPO administration alone or removal of a single Tfr2 allele increased hemoglobin levels and RBCs. However, EPO or Tfr2 single-allele deletion alone, respectively, exacerbated or did not improve splenomegaly in β-thalassemic mice. To overcome this issue, we postulated that some level of iron restriction (by targeting Tmprss6) would improve splenomegaly while preserving the beneficial effects on RBC production mediated by EPO or Tfr2 deletion. While administration of Tmprss6-ASO alone improved the anemia, the combination of Tmprss6-ASO + EPO or Tmprss6-ASO + Tfr2 single-allele deletion produced significantly higher hemoglobin levels and reduced splenomegaly. In conclusion, our results clearly indicate that these combinatorial approaches are superior to single treatments in ameliorating IE and anemia in β-thalassemia and could provide guidance to translate some of these approaches into viable therapies., (© 2020 by The American Society of Hematology.)
- Published
- 2020
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6. Heparanase Level and Procoagulant Activity Are Increased in Thalassemia and Attenuated by Janus Kinase 2 Inhibition.
- Author
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Ghoti H, Ackerman S, Rivella S, Casu C, and Nadir Y
- Subjects
- Adult, Animals, Humans, Male, Mice, Inbred C57BL, Thalassemia drug therapy, Thalassemia metabolism, Thromboplastin metabolism, Thrombosis metabolism, Young Adult, Blood Coagulation drug effects, Blood Coagulation physiology, Glucuronidase metabolism, Janus Kinase 2 antagonists & inhibitors, Lipoproteins pharmacology, Thrombosis drug therapy
- Abstract
Patients with thalassemia exhibit an increased risk of thrombotic events that is augmented after splenectomy. Heparanase protein enhances cancer progression, angiogenesis, and inflammation; it also activates the coagulation system through direct interaction with tissue factor (TF). Additionally, erythropoietin, which is elevated in anemic patients, up-regulates heparanase expression via the Janus kinase 2 (JAK-2) pathway. This study aimed was to explore the heparanase profile in thalassemia. Coagulation factors were analyzed via immunostaining, enzyme-linked immunosorbent assay, and heparanase procoagulant activity assay. In spleen specimens of thalassemia major patients, a higher level of heparanase staining was observed compared with control spleens resected after trauma (P < 0.001). Higher heparanase levels, heparanase and TF procoagulant activity, and erythropoietin levels were found in the plasma of 67 thalassemia major patients compared with 29 control subjects. No difference was found in pediatric patients (23 of 67) compared with adults or splenectomized versus nonsplenectomized patients. Higher levels of heparanase, TF, TF pathway inhibitor, and TF pathway inhibitor-2 were observed in liver, spleen, heart, and kidney tissues of thalassemia intermedia mice (Hbb
th3/+ ). These protein levels significantly reduced when mice were treated with the JAK-2 inhibitor ruxolitinib (P < 0.0001). In summary, heparanase levels are elevated in thalassemia, which may contribute to thrombotic phenomena in these patients. Inhibition of heparanase or the JAK-2 pathway may reduce thrombotic risk in thalassemia., (Copyright © 2020 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.)- Published
- 2020
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7. Lobe specificity of iron binding to transferrin modulates murine erythropoiesis and iron homeostasis.
- Author
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Parrow NL, Li Y, Feola M, Guerra A, Casu C, Prasad P, Mammen L, Ali F, Vaicikauskas E, Rivella S, Ginzburg YZ, and Fleming RE
- Subjects
- Animals, Binding Sites, Erythrocyte Count, Erythropoietin metabolism, Female, Homeostasis, Male, Mice, Mice, Transgenic, Mutagenesis, Site-Directed, Proto-Oncogene Proteins c-akt metabolism, Transferrin chemistry, Transferrin genetics, Erythropoiesis, Iron metabolism, Transferrin metabolism
- Abstract
Transferrin, the major plasma iron-binding molecule, interacts with cell-surface receptors to deliver iron, modulates hepcidin expression, and regulates erythropoiesis. Transferrin binds and releases iron via either or both of 2 homologous lobes (N and C). To test the hypothesis that the specificity of iron occupancy in the N vs C lobe influences transferrin function, we generated mice with mutations to abrogate iron binding in either lobe (TfN-bl or TfC-bl). Mice homozygous for either mutation had hepatocellular iron loading and decreased liver hepcidin expression (relative to iron concentration), although to different magnitudes. Both mouse models demonstrated some aspects of iron-restricted erythropoiesis, including increased zinc protoporphyrin levels, decreased hemoglobin levels, and microcytosis. Moreover, the TfN-bl/N-bl mice demonstrated the anticipated effect of iron restriction on red cell production (ie, no increase in red blood cell [RBC] count despite elevated erythropoietin levels), along with a poor response to exogenous erythropoietin. In contrast, the TfC-bl/C-bl mice had elevated RBC counts and an exaggerated response to exogenous erythropoietin sufficient to ameliorate the anemia. Observations in heterozygous mice further support a role for relative N vs C lobe iron occupancy in transferrin-mediated regulation of iron homeostasis and erythropoiesis., (© 2019 by The American Society of Hematology.)
- Published
- 2019
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8. Lack of Gdf11 does not improve anemia or prevent the activity of RAP-536 in a mouse model of β-thalassemia.
- Author
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Guerra A, Oikonomidou PR, Sinha S, Zhang J, Lo Presti V, Hamilton CR, Breda L, Casu C, La P, Martins AC, Sendamarai AK, Fleming M, and Rivella S
- Subjects
- Anemia blood, Anemia drug therapy, Anemia etiology, Animals, Biomarkers, Bone Morphogenetic Proteins genetics, Bone Morphogenetic Proteins metabolism, Disease Models, Animal, Growth Differentiation Factors genetics, Growth Differentiation Factors metabolism, Mice, Mice, Transgenic, Treatment Outcome, beta-Thalassemia blood, beta-Thalassemia drug therapy, beta-Thalassemia genetics, Bone Morphogenetic Proteins deficiency, Growth Differentiation Factors deficiency, Recombinant Fusion Proteins pharmacology, beta-Thalassemia metabolism
- Published
- 2019
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9. Iron metabolism under conditions of ineffective erythropoiesis in β-thalassemia.
- Author
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Rivella S
- Subjects
- Animals, Humans, beta-Thalassemia pathology, Erythropoiesis, Iron metabolism, Iron Metabolism Disorders etiology, Iron Metabolism Disorders pathology, beta-Thalassemia complications
- Abstract
β-Thalassemia (BT) is an inherited genetic disorder that is characterized by ineffective erythropoiesis (IE), leading to anemia and abnormal iron metabolism. IE is an abnormal expansion of the number of erythroid progenitor cells with unproductive synthesis of enucleated erythrocytes, leading to anemia and hypoxia. Anemic patients affected by BT suffer from iron overload, even in the absence of chronic blood transfusion, suggesting the presence of ≥1 erythroid factor with the ability to modulate iron metabolism and dietary iron absorption. Recent studies suggest that decreased erythroid cell differentiation and survival also contribute to IE, aggravating the anemia in BT. Furthermore, hypoxia can also affect and increase iron absorption. Understanding the relationship between iron metabolism and IE could provide important insights into the BT condition and help to develop novel treatments. In fact, genetic or pharmacological manipulations of iron metabolism or erythroid cell differentiation and survival have been shown to improve IE, iron overload, and anemia in animal models of BT. Based on those findings, new therapeutic approaches and drugs have been proposed; clinical trials are underway that have the potential to improve erythrocyte production, as well as to reduce the iron overload and organ toxicity in BT and in other disorders characterized by IE., (© 2019 by The American Society of Hematology.)
- Published
- 2019
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10. Interleukin-6 Contributes to the Development of Anemia in Juvenile CKD.
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Akchurin O, Patino E, Dalal V, Meza K, Bhatia D, Brovender S, Zhu YS, Cunningham-Rundles S, Perelstein E, Kumar J, Rivella S, and Choi ME
- Abstract
Introduction: Anemia is a common complication of chronic kidney disease (CKD) in children; however, the role of inflammation in its pathogenesis remains incompletely understood., Methods: To elucidate the role of interleukin (IL)-6 in renal anemia, we induced CKD by adenine diet in juvenile wild-type (WT) and IL-6 deficient ( Il6 KO) mice, and examined serum IL-6 and relevant parameters in children with CKD., Results: WT-CKD mice developed anemia despite increases in serum erythropoietin and displayed low serum iron and elevated serum IL-6. IL-6 deficiency resulted in a significant improvement of red blood cell count and hemoglobin in CKD mice. This effect was associated with improvement of hypoferremia by Il6 deletion, likely mediated by hepcidin. However, correction of hypoferremia by oral iron supplementation in WT-CKD mice did not fully replicate the protective effects of Il6 deletion, suggesting an additional iron-independent role for IL-6 in CKD-anemia. Indeed, Il6 deletion mitigated the severity of renal fibrosis and alleviated relative erythropoietin insufficiency in CKD mice. Cytokine profiling in a pediatric CKD cohort demonstrated that of 10 cytokines (IL-1β, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12, IL-13, tumor necrosis factor (TNF)-α, and interferon-γ), only IL-6 was significantly (inversely) associated with hemoglobin when adjusted for glomerular filtration rate (GFR). The association between IL-6 and hemoglobin in children with CKD remained significant after adjustment for CKD stage, iron therapy, and hepcidin., Discussion: IL-6 contributes to development of anemia in juvenile CKD, through mechanisms that include induction of hypoferremia, aggravation of renal fibrosis, and alteration of the erythropoietin axis. IL-6 appears to be a promising therapeutic target in the management of CKD-anemia.
- Published
- 2018
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11. Hepcidin agonists as therapeutic tools.
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Casu C, Nemeth E, and Rivella S
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- Animals, Hemochromatosis metabolism, Hemochromatosis pathology, Hepcidins metabolism, Humans, Iron metabolism, Polycythemia Vera metabolism, Polycythemia Vera pathology, beta-Thalassemia metabolism, beta-Thalassemia pathology, Hemochromatosis drug therapy, Hepcidins agonists, Polycythemia Vera drug therapy, beta-Thalassemia drug therapy
- Abstract
Hepcidin agonists are a new class of compounds that regulate blood iron levels, limit iron absorption, and could improve the treatment of hemochromatosis, β-thalassemia, polycythemia vera, and other disorders in which disrupted iron homeostasis causes or contributes to disease. Hepcidin agonists also have the potential to prevent severe complications of siderophilic infections in patients with iron overload or chronic liver disease. This review highlights the preclinical studies that support the development of hepcidin agonists for the treatment of these disorders., (© 2018 by The American Society of Hematology.)
- Published
- 2018
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12. What can we learn from ineffective erythropoiesis in thalassemia?
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Oikonomidou PR and Rivella S
- Subjects
- Animals, Biomarkers, Cell Differentiation, Erythrocytes drug effects, Erythrocytes metabolism, Hematopoietic Stem Cells cytology, Hematopoietic Stem Cells metabolism, Humans, Iron metabolism, Molecular Targeted Therapy, Stress, Physiological, Thalassemia blood, Thalassemia drug therapy, Erythropoiesis drug effects, Erythropoiesis genetics, Thalassemia etiology, Thalassemia metabolism
- Abstract
Erythropoiesis is a dynamic process regulated at multiple levels to balance proliferation, differentiation and survival of erythroid progenitors. Ineffective erythropoiesis is a key feature of various diseases, including β-thalassemia. The pathogenic mechanisms leading to ineffective erythropoiesis are complex and still not fully understood. Altered survival and decreased differentiation of erythroid progenitors are both critical processes contributing to reduced production of mature red blood cells. Recent studies have identified novel important players and provided major advances in the development of targeted therapeutic approaches. In this review, β-thalassemia is used as a paradigmatic example to describe our current knowledge on the mechanisms leading to ineffective erythropoiesis and novel treatments that may have the potential to improve the clinical phenotype of associated diseases in the future., (Copyright © 2017 Elsevier Ltd. All rights reserved.)
- Published
- 2018
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13. Structure-function analysis of ferroportin defines the binding site and an alternative mechanism of action of hepcidin.
- Author
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Aschemeyer S, Qiao B, Stefanova D, Valore EV, Sek AC, Ruwe TA, Vieth KR, Jung G, Casu C, Rivella S, Jormakka M, Mackenzie B, Ganz T, and Nemeth E
- Subjects
- Animals, Binding Sites, Cation Transport Proteins genetics, Cells, Cultured, Computer Simulation, Endocytosis, HEK293 Cells, Hepcidins agonists, Humans, Mice, Mice, Inbred C57BL, Mutagenesis, Site-Directed, Mutation, Oocytes cytology, Oocytes metabolism, Protein Binding, Protein Conformation, Protein Domains, Structure-Activity Relationship, Ubiquitination, Xenopus laevis, Cation Transport Proteins chemistry, Cation Transport Proteins metabolism, Drug Resistance, Hepcidins metabolism, Iron metabolism
- Abstract
Nonclassical ferroportin disease (FD) is a form of hereditary hemochromatosis caused by mutations in the iron transporter ferroportin (Fpn), resulting in parenchymal iron overload. Fpn is regulated by the hormone hepcidin, which induces Fpn endocytosis and cellular iron retention. We characterized 11 clinically relevant and 5 nonclinical Fpn mutations using stably transfected, inducible isogenic cell lines. All clinical mutants were functionally resistant to hepcidin as a consequence of either impaired hepcidin binding or impaired hepcidin-dependent ubiquitination despite intact hepcidin binding. Mapping the residues onto 2 computational models of the human Fpn structure indicated that (1) mutations that caused ubiquitination-resistance were positioned at helix-helix interfaces, likely preventing the hepcidin-induced conformational change, (2) hepcidin binding occurred within the central cavity of Fpn, (3) hepcidin interacted with up to 4 helices, and (4) hepcidin binding should occlude Fpn and interfere with iron export independently of endocytosis. We experimentally confirmed hepcidin-mediated occlusion of Fpn in the absence of endocytosis in multiple cellular systems: HEK293 cells expressing an endocytosis-defective Fpn mutant (K8R), Xenopus oocytes expressing wild-type or K8R Fpn, and mature human red blood cells. We conclude that nonclassical FD is caused by Fpn mutations that decrease hepcidin binding or hinder conformational changes required for ubiquitination and endocytosis of Fpn. The newly documented ability of hepcidin and its agonists to occlude iron transport may facilitate the development of broadly effective treatments for hereditary iron overload disorders., (© 2018 by The American Society of Hematology.)
- Published
- 2018
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14. Efficacy and safety of ruxolitinib in regularly transfused patients with thalassemia: results from a phase 2a study.
- Author
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Taher AT, Karakas Z, Cassinerio E, Siritanaratkul N, Kattamis A, Maggio A, Rivella S, Hollaender N, Mahuzier B, Gadbaw B, and Aydinok Y
- Subjects
- Erythroid Cells, Erythropoiesis, Humans, Nitriles, Pyrazoles, Pyrimidines, Thalassemia, beta-Thalassemia
- Published
- 2018
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15. Tropomodulin 1 controls erythroblast enucleation via regulation of F-actin in the enucleosome.
- Author
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Nowak RB, Papoin J, Gokhin DS, Casu C, Rivella S, Lipton JM, Blanc L, and Fowler VM
- Subjects
- Animals, Bone Marrow metabolism, Cell Differentiation, Cell Nucleus Shape, Cell Polarity, Fetus metabolism, Gene Knockdown Techniques, Lamins metabolism, Liver embryology, Mice, Inbred C57BL, Nonmuscle Myosin Type IIB metabolism, Protein Isoforms metabolism, Actins metabolism, Cell Nucleus metabolism, Erythroblasts metabolism, Tropomodulin metabolism
- Abstract
Biogenesis of mammalian red blood cells requires nuclear expulsion by orthochromatic erythoblasts late in terminal differentiation (enucleation), but the mechanism is largely unexplained. Here, we employed high-resolution confocal microscopy to analyze nuclear morphology and F-actin rearrangements during the initiation, progression, and completion of mouse and human erythroblast enucleation in vivo. Mouse erythroblast nuclei acquire a dumbbell-shaped morphology during enucleation, whereas human bone marrow erythroblast nuclei unexpectedly retain their spherical morphology. These morphological differences are linked to differential expression of Lamin isoforms, with primary mouse erythroblasts expressing only Lamin B and primary human erythroblasts only Lamin A/C. We did not consistently identify a continuous F-actin ring at the cell surface constriction in mouse erythroblasts, nor at the membrane protein-sorting boundary in human erythroblasts, which do not have a constriction, arguing against a contractile ring-based nuclear expulsion mechanism. However, both mouse and human erythroblasts contain an F-actin structure at the rear of the translocating nucleus, enriched in tropomodulin 1 (Tmod1) and nonmuscle myosin IIB. We investigated Tmod1 function in mouse and human erythroblasts both in vivo and in vitro and found that absence of Tmod1 leads to enucleation defects in mouse fetal liver erythroblasts, and in CD34
+ hematopoietic stem and progenitor cells, with increased F-actin in the structure at the rear of the nucleus. This novel structure, the "enucleosome," may mediate common cytoskeletal mechanisms underlying erythroblast enucleation, notwithstanding the morphological heterogeneity of enucleation across species., (© 2017 by The American Society of Hematology.)- Published
- 2017
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16. Decreasing TfR1 expression reverses anemia and hepcidin suppression in β-thalassemic mice.
- Author
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Li H, Choesang T, Bao W, Chen H, Feola M, Garcia-Santos D, Li J, Sun S, Follenzi A, Pham P, Liu J, Zhang J, Ponka P, An X, Mohandas N, Fleming RE, Rivella S, Li G, and Ginzburg YZ
- Subjects
- Anemia prevention & control, Animals, Apoproteins administration & dosage, Apoproteins pharmacokinetics, Erythropoiesis, Iron Overload etiology, Mice, Transferrin administration & dosage, Transferrin pharmacokinetics, Anemia etiology, Hepcidins metabolism, Receptors, Transferrin metabolism, beta-Thalassemia metabolism
- Abstract
Iron availability for erythropoiesis and its dysregulation in β-thalassemia are incompletely understood. We previously demonstrated that exogenous apotransferrin leads to more effective erythropoiesis, decreasing erythroferrone (ERFE) and derepressing hepcidin in β-thalassemic mice. Transferrin-bound iron binding to transferrin receptor 1 (TfR1) is essential for cellular iron delivery during erythropoiesis. We hypothesize that apotransferrin's effect is mediated via decreased TfR1 expression and evaluate TfR1 expression in β-thalassemic mice in vivo and in vitro with and without added apotransferrin. Our findings demonstrate that β-thalassemic erythroid precursors overexpress TfR1, an effect that can be reversed by the administration of exogenous apotransferrin. In vitro experiments demonstrate that apotransferrin inhibits TfR1 expression independent of erythropoietin- and iron-related signaling, decreases TfR1 partitioning to reticulocytes during enucleation, and enhances enucleation of defective β-thalassemic erythroid precursors. These findings strongly suggest that overexpressed TfR1 may play a regulatory role contributing to iron overload and anemia in β-thalassemic mice. To evaluate further, we crossed TfR1
+/- mice, themselves exhibiting iron-restricted erythropoiesis with increased hepcidin, with β-thalassemic mice. Resultant double-heterozygote mice demonstrate long-term improvement in ineffective erythropoiesis, hepcidin derepression, and increased erythroid enucleation in relation to β-thalassemic mice. Our data demonstrate for the first time that TfR1+/- haploinsufficiency reverses iron overload specifically in β-thalassemic erythroid precursors. Taken together, decreasing TfR1 expression during β-thalassemic erythropoiesis, either directly via induced haploinsufficiency or via exogenous apotransferrin, decreases ineffective erythropoiesis and provides an endogenous mechanism to upregulate hepcidin, leading to sustained iron-restricted erythropoiesis and preventing systemic iron overload in β-thalassemic mice., (© 2017 by The American Society of Hematology.)- Published
- 2017
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17. Forced chromatin looping raises fetal hemoglobin in adult sickle cells to higher levels than pharmacologic inducers.
- Author
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Breda L, Motta I, Lourenco S, Gemmo C, Deng W, Rupon JW, Abdulmalik OY, Manwani D, Blobel GA, and Rivella S
- Subjects
- Adult, Antigens, CD34 metabolism, DNA-Binding Proteins, Erythroid Cells metabolism, Hemoglobin, Sickle, Humans, LIM Domain Proteins, Transcription Factors, Zinc Fingers, Anemia, Sickle Cell metabolism, Chromatin metabolism, Fetal Hemoglobin metabolism
- Abstract
Overcoming the silencing of the fetal γ-globin gene has been a long-standing goal in the treatment of sickle cell disease (SCD). The major transcriptional enhancer of the β-globin locus, called the locus control region (LCR), dynamically interacts with the developmental stage-appropriate β-type globin genes via chromatin looping, a process requiring the protein Ldb1. In adult erythroid cells, the LCR can be redirected from the adult β- to the fetal γ-globin promoter by tethering Ldb1 to the human γ-globin promoter with custom-designed zinc finger (ZF) proteins (ZF-Ldb1), leading to reactivation of γ-globin gene expression. To compare this approach to pharmacologic reactivation of fetal hemoglobin (HbF), hematopoietic cells from patients with SCD were treated with a lentivirus expressing the ZF-Ldb1 or with chemical HbF inducers. The HbF increase in cells treated with ZF-Ldb1 was more than double that observed with decitabine and pomalidomide; butyrate had an intermediate effect whereas tranylcypromine and hydroxyurea showed relatively low HbF reactivation. ZF-Ldb1 showed comparatively little toxicity, and reduced sickle hemoglobin (HbS) synthesis as well as sickling of SCD erythroid cells under hypoxic conditions. The efficacy and low cytotoxicity of lentiviral-mediated ZF-Ldb1 gene transfer compared with the drug regimens support its therapeutic potential for the treatment of SCD., (© 2016 by The American Society of Hematology.)
- Published
- 2016
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18. Minihepcidin peptides as disease modifiers in mice affected by β-thalassemia and polycythemia vera.
- Author
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Casu C, Oikonomidou PR, Chen H, Nandi V, Ginzburg Y, Prasad P, Fleming RE, Shah YM, Valore EV, Nemeth E, Ganz T, MacDonald B, and Rivella S
- Subjects
- Amino Acid Substitution, Animals, Hepcidins genetics, Hepcidins metabolism, Janus Kinase 2 genetics, Janus Kinase 2 metabolism, Mice, Mice, Mutant Strains, Mutation, Missense, Peptides genetics, Peptides metabolism, Polycythemia Vera genetics, beta-Thalassemia genetics, Erythropoiesis, Hepcidins pharmacology, Peptides pharmacology, Polycythemia Vera metabolism, beta-Thalassemia metabolism
- Abstract
In β-thalassemia and polycythemia vera (PV), disordered erythropoiesis triggers severe pathophysiological manifestations. β-Thalassemia is characterized by ineffective erythropoiesis, reduced production of erythrocytes, anemia, and iron overload and PV by erythrocytosis and thrombosis. Minihepcidins are hepcidin agonists that have been previously shown to prevent iron overload in murine models of hemochromatosis and induce iron-restricted erythropoiesis at higher doses. Here, we show that in young Hbb(th3/+) mice, which serve as a model of untransfused β-thalassemia, minihepcidin ameliorates ineffective erythropoiesis, anemia, and iron overload. In older mice with untransfused β-thalassemia, minihepcidin improves erythropoiesis and does not alter the beneficial effect of the iron chelator deferiprone on iron overload. In PV mice that express the orthologous JAK2 mutation causing human PV, administration of minihepcidin significantly reduces splenomegaly and normalizes hematocrit levels. These studies indicate that drug-like minihepcidins have a potential as future therapeutics for untransfused β-thalassemia and PV., (© 2016 by The American Society of Hematology.)
- Published
- 2016
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19. Modified activin receptor IIB ligand trap mitigates ineffective erythropoiesis and disease complications in murine β-thalassemia.
- Author
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Suragani RN, Cawley SM, Li R, Wallner S, Alexander MJ, Mulivor AW, Gardenghi S, Rivella S, Grinberg AV, Pearsall RS, and Kumar R
- Subjects
- Activin Receptors, Type II metabolism, Anemia blood, Anemia genetics, Anemia prevention & control, Animals, Blotting, Western, Cell Differentiation drug effects, Cell Differentiation genetics, Erythrocytes drug effects, Erythrocytes metabolism, Erythroid Precursor Cells drug effects, Erythroid Precursor Cells metabolism, Erythropoiesis genetics, Hemolysis drug effects, Hemolysis genetics, Humans, Immunoglobulin Fc Fragments genetics, Immunoglobulin Fc Fragments metabolism, Immunoglobulin G genetics, Immunoglobulin G metabolism, Iron Overload metabolism, Iron Overload prevention & control, Mice, Mice, Inbred C57BL, Mice, Knockout, Mutation, Reactive Oxygen Species metabolism, Recombinant Fusion Proteins genetics, Recombinant Fusion Proteins metabolism, Signal Transduction genetics, Smad2 Protein metabolism, Smad3 Protein metabolism, beta-Globins genetics, beta-Globins metabolism, beta-Thalassemia blood, beta-Thalassemia genetics, Activin Receptors, Type II genetics, Erythropoiesis drug effects, Recombinant Fusion Proteins pharmacology, Signal Transduction drug effects, beta-Thalassemia drug therapy
- Abstract
In β-thalassemia, unequal production of α- and β-globin chains in erythroid precursors causes apoptosis and inhibition of late-stage erythroid differentiation, leading to anemia, ineffective erythropoiesis (IE), and dysregulated iron homeostasis. Here we used a murine model of β-thalassemia intermedia (Hbb(th1/th1) mice) to investigate effects of a modified activin receptor type IIB (ActRIIB) ligand trap (RAP-536) that inhibits Smad2/3 signaling. In Hbb(th1/th1) mice, treatment with RAP-536 reduced overactivation of Smad2/3 in splenic erythroid precursors. In addition, treatment of Hbb(th1/th1) mice with RAP-536 reduced α-globin aggregates in peripheral red cells, decreased the elevated reactive oxygen species present in erythroid precursors and peripheral red cells, and alleviated anemia by promoting differentiation of late-stage erythroid precursors and reducing hemolysis. Notably, RAP-536 treatment mitigated disease complications of IE, including iron overload, splenomegaly, and bone pathology, while reducing erythropoietin levels, improving erythrocyte morphology, and extending erythrocyte life span. These results implicate signaling by the transforming growth factor-β superfamily in late-stage erythropoiesis and reveal potential of a modified ActRIIB ligand trap as a novel therapeutic agent for thalassemia syndrome and other red cell disorders characterized by IE., (© 2014 by The American Society of Hematology.)
- Published
- 2014
- Full Text
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20. β-Thalassemia and Polycythemia vera: targeting chronic stress erythropoiesis.
- Author
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Crielaard BJ and Rivella S
- Subjects
- Animals, Humans, Erythropoiesis physiology, Polycythemia Vera blood, beta-Thalassemia blood
- Abstract
β-Thalassemia and Polycythemia vera are genetic disorders which affect the synthesis of red blood cells, also referred to as erythropoiesis. Although essentially different in clinical presentation - patients with β-thalassemia have an impairment in β-globin synthesis leading to defective erythrocytes and anemia, while patients with Polycythemia vera present with high hemoglobin levels because of excessive red blood cell synthesis - both pathologies may characterized by lasting high erythropoietic activity, i.e. chronic stress erythropoiesis. In both diseases, therapeutic strategies targeting chronic stress erythropoiesis may improve the address phenotype and prevent secondary pathology, such as iron overload. The current review will address the basic concepts of these strategies to reduce chronic stress erythropoiesis, which may have significant clinical implications in the near future., (Copyright © 2014 Elsevier Ltd. All rights reserved.)
- Published
- 2014
- Full Text
- View/download PDF
21. Distinct roles for hepcidin and interleukin-6 in the recovery from anemia in mice injected with heat-killed Brucella abortus.
- Author
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Gardenghi S, Renaud TM, Meloni A, Casu C, Crielaard BJ, Bystrom LM, Greenberg-Kushnir N, Sasu BJ, Cooke KS, and Rivella S
- Subjects
- Anemia genetics, Anemia microbiology, Animals, Bone Marrow immunology, Brucellosis complications, Disease Models, Animal, Erythropoiesis immunology, Female, Hepcidins genetics, Hot Temperature, Interleukin-6 genetics, Male, Mice, Mice, Inbred C57BL, Mice, Knockout, Recovery of Function immunology, Anemia immunology, Brucella abortus, Brucellosis immunology, Hepcidins immunology, Interleukin-6 immunology
- Abstract
Anemia of inflammation (AI) is commonly observed in chronic inflammatory states and may hinder patient recovery and survival. Induction of hepcidin, mediated by interleukin 6, leads to iron-restricted erythropoiesis and anemia. Several translational studies have been directed at neutralizing hepcidin overexpression as a therapeutic strategy against AI. However, additional hepcidin-independent mechanisms contribute to AI, which are likely mediated by a direct effect of inflammatory cytokines on erythropoiesis. In this study, we used wild-type, hepcidin knockout (Hamp-KO) and interleukin 6 knockout (IL-6-KO) mice as models of AI. AI was induced with heat-killed Brucella abortus (BA). The distinct roles of iron metabolism and inflammation triggered by interleukin 6 and hepcidin were investigated. BA-treated wild-type mice showed increased expression of hepcidin and inflammatory cytokines, as well as transitory suppression of erythropoiesis and shortened red blood cell lifespan, all of which contributed to the severe anemia of these mice. In contrast, BA-treated Hamp-KO or IL-6-KO mice showed milder anemia and faster recovery compared with normal mice. Moreover, they exhibited different patterns in the development and resolution of anemia, supporting the notion that interleukin 6 and hepcidin play distinct roles in modulating erythropoiesis in AI.
- Published
- 2014
- Full Text
- View/download PDF
22. Enucleate or replicate? Ask the cytoskeleton.
- Author
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Rivella S
- Subjects
- Animals, Female, Male, Erythroid Precursor Cells metabolism, Gene Deletion, Liver embryology, Tropomodulin genetics
- Abstract
In this issue of Blood, Sui and colleagues have identified novel and interesting roles for Tropomodulin (Tmod)-3, a protein involved with actin filament organization, in erythroid proliferation, survival, and enucleation.
- Published
- 2014
- Full Text
- View/download PDF
23. Gene therapy for hemoglobinopathies: progress and challenges.
- Author
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Dong A, Rivella S, and Breda L
- Subjects
- Animals, Clinical Trials as Topic, Disease Models, Animal, Fetal Hemoglobin metabolism, Humans, Phenotype, Genetic Therapy, Hemoglobinopathies genetics, Hemoglobinopathies therapy
- Abstract
Hemoglobinopathies are genetic inherited conditions that originate from the lack or malfunction of the hemoglobin (Hb) protein. Sickle cell disease (SCD) and thalassemia are the most common forms of these conditions. The severe anemia combined with complications that arise in the most affected patients raises the necessity for a cure to restore hemoglobin function. The current routine therapies for these conditions, namely transfusion and iron chelation, have significantly improved the quality of life in patients over the years, but still fail to address the underlying cause of the diseases. A curative option, allogeneic bone marrow transplantation is available, but limited by the availability of suitable donors and graft-vs-host disease. Gene therapy offers an alternative approach to cure patients with hemoglobinopathies and aims at the direct recovery of the hemoglobin function via globin gene transfer. In the last 2 decades, gene transfer tools based on lentiviral vector development have been significantly improved and proven curative in several animal models for SCD and thalassemia. As a result, clinical trials are in progress and 1 patient has been successfully treated with this approach. However, there are still frontiers to explore that might improve this approach: the stoichiometry between the transgenic hemoglobin and endogenous hemoglobin with respect to the different globin genetic mutations; donor cell sourcing, such as the use of induced pluripotent stem cells (iPSCs); and the use of safer gene insertion methods to prevent oncogenesis. With this review we will provide insights about (1) the different lentiviral gene therapy approaches in mouse models and human cells; (2) current and planned clinical trials; (3) hurdles to overcome for clinical trials, such as myeloablation toxicity, insertional oncogenesis, and high vector expression; and (4) future perspectives for gene therapy, including safe harbors and iPSCs technology., (Copyright © 2013 Mosby, Inc. All rights reserved.)
- Published
- 2013
- Full Text
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24. Do not super-excess me!
- Author
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Rivella S
- Subjects
- Animals, Bortezomib, Female, Humans, Male, Alpha-Globulins metabolism, Antineoplastic Agents pharmacology, Boronic Acids pharmacology, Erythroid Precursor Cells metabolism, Proteasome Inhibitors, Proteolysis drug effects, Pyrazines pharmacology, Ubiquitination drug effects, beta-Thalassemia drug therapy
- Published
- 2012
- Full Text
- View/download PDF
25. The role of ineffective erythropoiesis in non-transfusion-dependent thalassemia.
- Author
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Rivella S
- Subjects
- Animals, Blood Transfusion, Humans, Iron metabolism, beta-Thalassemia metabolism, beta-Thalassemia pathology, Erythropoiesis physiology, beta-Thalassemia blood
- Abstract
Ineffective erythropoiesis is the hallmark of beta-thalassemia that triggers a cascade of compensatory mechanisms resulting in clinical sequelae such as erythroid marrow expansion, extramedullary hematopoiesis, splenomegaly, and increased gastrointestinal iron absorption. Recent studies have begun to shed light on the complex molecular mechanisms underlying ineffective erythropoiesis and the associated compensatory pathways; this new understanding may lead to the development of novel therapies. Increased or excessive activation of the Jak2/STAT5 pathway promotes unnecessary disproportionate proliferation of erythroid progenitors, while other factors suppress serum hepcidin levels leading to dysregulation of iron metabolism. Preclinical studies suggest that Jak inhibitors, hepcidin agonists, and exogenous transferrin may help to restore normal erythropoiesis and iron metabolism and reduce splenomegaly; however, further research is needed., (Copyright © 2012 Elsevier Ltd. All rights reserved.)
- Published
- 2012
- Full Text
- View/download PDF
26. Decreased hepcidin expression in murine β-thalassemia is associated with suppression of Bmp/Smad signaling.
- Author
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Parrow NL, Gardenghi S, Ramos P, Casu C, Grady RW, Anderson ER, Shah YM, Li H, Ginzburg YZ, Fleming RE, and Rivella S
- Subjects
- Animals, Antimicrobial Cationic Peptides metabolism, Bone Morphogenetic Protein 6 genetics, Bone Morphogenetic Protein 6 metabolism, Bone Morphogenetic Proteins genetics, Bone Morphogenetic Proteins metabolism, Down-Regulation genetics, Gene Expression Regulation, Hepcidins, Iron metabolism, Iron Overload genetics, Iron Overload metabolism, Liver metabolism, Liver pathology, Mice, Mice, Inbred C57BL, Mice, Transgenic, Signal Transduction genetics, Signal Transduction physiology, Smad Proteins genetics, Smad Proteins metabolism, beta-Thalassemia metabolism, beta-Thalassemia pathology, Antimicrobial Cationic Peptides genetics, Bone Morphogenetic Proteins physiology, Smad Proteins physiology, beta-Thalassemia genetics
- Published
- 2012
- Full Text
- View/download PDF
27. β-thalassemia: a model for elucidating the dynamic regulation of ineffective erythropoiesis and iron metabolism.
- Author
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Ginzburg Y and Rivella S
- Subjects
- Animals, Antimicrobial Cationic Peptides metabolism, Disease Models, Animal, Erythrocytes pathology, Hepcidins, Humans, beta-Thalassemia pathology, Erythrocytes metabolism, Erythropoiesis, Iron metabolism, beta-Thalassemia metabolism, beta-Thalassemia therapy
- Abstract
β-thalassemia is a disease characterized by anemia and is associated with ineffective erythropoiesis and iron dysregulation resulting in iron overload. The peptide hormone hepcidin regulates iron metabolism, and insufficient hepcidin synthesis is responsible for iron overload in minimally transfused patients with this disease. Understanding the crosstalk between erythropoiesis and iron metabolism is an area of active investigation in which patients with and models of β-thalassemia have provided significant insight. The dependence of erythropoiesis on iron presupposes that iron demand for hemoglobin synthesis is involved in the regulation of iron metabolism. Major advances have been made in understanding iron availability for erythropoiesis and its dysregulation in β-thalassemia. In this review, we describe the clinical characteristics and current therapeutic standard in β-thalassemia, explore the definition of ineffective erythropoiesis, and discuss its role in hepcidin regulation. In preclinical experiments using interventions such as transferrin, hepcidin agonists, and JAK2 inhibitors, we provide evidence of potential new treatment alternatives that elucidate mechanisms by which expanded or ineffective erythropoiesis may regulate iron supply, distribution, and utilization in diseases such as β-thalassemia.
- Published
- 2011
- Full Text
- View/download PDF
28. Enhanced erythropoiesis in Hfe-KO mice indicates a role for Hfe in the modulation of erythroid iron homeostasis.
- Author
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Ramos P, Guy E, Chen N, Proenca CC, Gardenghi S, Casu C, Follenzi A, Van Rooijen N, Grady RW, de Sousa M, and Rivella S
- Subjects
- Aging blood, Aging metabolism, Aging physiology, Animals, Animals, Newborn, Antimicrobial Cationic Peptides genetics, Antimicrobial Cationic Peptides metabolism, Hemochromatosis Protein, Hepcidins, Histocompatibility Antigens Class I metabolism, Histocompatibility Antigens Class I physiology, Homeostasis genetics, Homeostasis physiology, Iron Overload genetics, Iron Overload metabolism, Membrane Proteins metabolism, Membrane Proteins physiology, Mice, Mice, Inbred C57BL, Mice, Knockout, Stress, Physiological genetics, Stress, Physiological physiology, Transferrin metabolism, Up-Regulation genetics, Up-Regulation physiology, Erythroid Cells metabolism, Erythropoiesis genetics, Histocompatibility Antigens Class I genetics, Iron metabolism, Membrane Proteins genetics
- Abstract
In hereditary hemochromatosis, mutations in HFE lead to iron overload through abnormally low levels of hepcidin. In addition, HFE potentially modulates cellular iron uptake by interacting with transferrin receptor, a crucial protein during erythropoiesis. However, the role of HFE in this process was never explored. We hypothesize that HFE modulates erythropoiesis by affecting dietary iron absorption and erythroid iron intake. To investigate this, we used Hfe-KO mice in conditions of altered dietary iron and erythropoiesis. We show that Hfe-KO mice can overcome phlebotomy-induced anemia more rapidly than wild-type mice (even when iron loaded). Second, we evaluated mice combining the hemochromatosis and β-thalassemia phenotypes. Our results suggest that lack of Hfe is advantageous in conditions of increased erythropoietic activity because of augmented iron mobilization driven by deficient hepcidin response. Lastly, we demonstrate that Hfe is expressed in erythroid cells and impairs iron uptake, whereas its absence exclusively from the hematopoietic compartment is sufficient to accelerate recovery from phlebotomy. In summary, we demonstrate that Hfe influences erythropoiesis by 2 distinct mechanisms: limiting hepcidin expression under conditions of simultaneous iron overload and stress erythropoiesis, and impairing transferrin-bound iron uptake by erythroid cells. Moreover, our results provide novel suggestions to improve the treatment of hemochromatosis.
- Published
- 2011
- Full Text
- View/download PDF
29. Decreased differentiation of erythroid cells exacerbates ineffective erythropoiesis in beta-thalassemia.
- Author
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Libani IV, Guy EC, Melchiori L, Schiro R, Ramos P, Breda L, Scholzen T, Chadburn A, Liu Y, Kernbach M, Baron-Lühr B, Porotto M, de Sousa M, Rachmilewitz EA, Hood JD, Cappellini MD, Giardina PJ, Grady RW, Gerdes J, and Rivella S
- Subjects
- Animals, Apoptosis, Cyclin-Dependent Kinases genetics, Janus Kinase 2 antagonists & inhibitors, Mice, Spleen pathology, Cell Differentiation, Erythroid Cells pathology, Erythropoiesis, Janus Kinase 2 genetics, beta-Thalassemia blood
- 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.
- Published
- 2008
- Full Text
- View/download PDF
30. Ineffective erythropoiesis in beta-thalassemia is characterized by increased iron absorption mediated by down-regulation of hepcidin and up-regulation of ferroportin.
- Author
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Gardenghi S, Marongiu MF, Ramos P, Guy E, Breda L, Chadburn A, Liu Y, Amariglio N, Rechavi G, Rachmilewitz EA, Breuer W, Cabantchik ZI, Wrighting DM, Andrews NC, de Sousa M, Giardina PJ, Grady RW, and Rivella S
- Subjects
- Animals, Blood Transfusion, Flow Cytometry, Hepcidins, Iron metabolism, Mice, Mice, Inbred C57BL, Mice, Transgenic, Phenotype, beta-Thalassemia metabolism, Antimicrobial Cationic Peptides biosynthesis, Cation Transport Proteins biosynthesis, Down-Regulation, Erythropoiesis, Gene Expression Regulation, Iron pharmacokinetics, Up-Regulation, beta-Thalassemia blood
- Abstract
Progressive iron overload is the most salient and ultimately fatal complication of beta-thalassemia. However, little is known about the relationship among ineffective erythropoiesis (IE), the role of iron-regulatory genes, and tissue iron distribution in beta-thalassemia. We analyzed tissue iron content and iron-regulatory gene expression in the liver, duodenum, spleen, bone marrow, kidney, and heart of mice up to 1 year old that exhibit levels of iron overload and anemia consistent with both beta-thalassemia intermedia (th3/+) and major (th3/th3). Here we show, for the first time, that tissue and cellular iron distribution are abnormal and different in th3/+ and th3/th3 mice, and that transfusion therapy can rescue mice affected by beta-thalassemia major and modify both the absorption and distribution of iron. Our study reveals that the degree of IE dictates tissue iron distribution and that IE and iron content regulate hepcidin (Hamp1) and other iron-regulatory genes such as Hfe and Cebpa. In young th3/+ and th3/th3 mice, low Hamp1 levels are responsible for increased iron absorption. However, in 1-year-old th3/+ animals, Hamp1 levels rise and it is rather the increase of ferroportin (Fpn1) that sustains iron accumulation, thus revealing a fundamental role of this iron transporter in the iron overload of beta-thalassemia.
- Published
- 2007
- Full Text
- View/download PDF
31. Globin gene transfer for treatment of the beta-thalassemias and sickle cell disease.
- Author
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Sadelain M, Rivella S, Lisowski L, Samakoglu S, and Rivière I
- Subjects
- Anemia, Sickle Cell therapy, Animals, Disease Models, Animal, Globins genetics, Humans, Mice, beta-Thalassemia therapy, Genetic Therapy methods, Globins therapeutic use, Hemoglobinopathies therapy
- Abstract
The beta-thalassemias and sickle cell disease are severe congenital anemias that are caused by mutations that alter the production of the beta chain of hemoglobin. Allogeneic hematopoietic stem cell (HSC) transplantation is curative, but this therapeutic option is not available to the majority of patients. The transfer of a functional globin gene in autologous HCSs thus represents a highly attractive alternative treatment. This strategy, simple in principle, raises major challenges in terms of controlling the expression of the globin transgene, which ideally should be erythroid specific, differentiation-stage restricted, elevated, position independent, and sustained over time. Using lentiviral vectors, we have demonstrated that an optimised combination of proximal and distal transcriptional control elements permits lineage-specific, elevated expression of the beta-globin gene, resulting in therapeutic hemoglobin production and correction of anemia in beta-thalassemic mice. Several groups have now confirmed and extended these findings in various mouse models of severe hemoglobinopathies, thus generating enthusiasm for a genetic treatment based on globin gene transfer. Furthermore, globin vectors represent a general paradigm for the regulation of transgene function and the improvement of vector safety by restricting transgene expression to the differentiated progeny within a single lineage, thereby reducing the risk of activating oncogenes in hematopoietic progenitors. Here we review the principles underlying the genesis of regulated vectors for stem cell therapy.
- Published
- 2004
- Full Text
- View/download PDF
32. A novel murine model of Cooley anemia and its rescue by lentiviral-mediated human beta-globin gene transfer.
- Author
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Rivella S, May C, Chadburn A, Rivière I, and Sadelain M
- Subjects
- Animals, Crosses, Genetic, Erythropoiesis, Feasibility Studies, Female, Gene Expression Profiling, Genes, Lethal, Genetic Vectors therapeutic use, Globins analysis, Humans, Iron Overload etiology, Iron Overload prevention & control, Liver cytology, Liver embryology, Male, Mice, Mice, Inbred C57BL, Mice, Knockout, Radiation Chimera, Recombinant Fusion Proteins blood, Recombinant Fusion Proteins genetics, Transduction, Genetic, beta-Thalassemia blood, beta-Thalassemia genetics, Disease Models, Animal, Genetic Therapy, Globins genetics, Hematopoietic Stem Cell Transplantation, beta-Thalassemia therapy
- Abstract
Patients affected by beta-thalassemia major require lifelong transfusions because of insufficient or absent production of the beta chain of hemoglobin (Hb). A minority of patients are cured by allogeneic bone marrow transplantation. In the most severe of the hitherto available mouse models of beta-thalassemia, a model for human beta-thalassemia intermedia, we previously demonstrated that globin gene transfer in bone marrow cells is curative, stably raising Hb levels from 8.0-8.5 to 11.0-12.0 g/dL in long-term chimeras. To fully assess the therapeutic potential of gene therapy in the context of a lethal anemia, we now have created an adult model of beta(0)-thalassemia major. In this novel model, mice engrafted with beta-globin-null (Hbb(th3/th3)) fetal liver cells succumb to ineffective erythropoiesis within 60 days. These mice rapidly develop severe anemia (2-4 g/dL), massive splenomegaly, extramedullary hematopoiesis (EMH), and hepatic iron overload. Remarkably, most mice (11 of 13) treated by lentivirus-mediated globin gene transfer were rescued. Long-term chimeras with an average 1.0-2.4 copies of the TNS9 vector in their hematopoietic and blood cells stably produced up to 12 g/dL chimeric Hb consisting of mu alpha(2):hu beta(2) tetramers. Pathologic analyses indicated that erythroid maturation was restored, while EMH and iron overload dramatically decreased. Thus, we have established an adult animal model for the most severe of the hemoglobinopathies, Cooley anemia, which should prove useful to investigate both genetic and pharmacologic treatments. Our findings demonstrate the remarkable efficacy of lentivirus-mediated globin gene transfer in treating a fulminant blood disorder and strongly support the efficacy of gene therapy in the severe hemoglobinopathies.
- Published
- 2003
- Full Text
- View/download PDF
33. Successful treatment of murine beta-thalassemia intermedia by transfer of the human beta-globin gene.
- Author
-
May C, Rivella S, Chadburn A, and Sadelain M
- Subjects
- Animals, Bone Marrow Cells metabolism, Bone Marrow Transplantation, Erythropoiesis drug effects, Erythropoiesis genetics, Globins administration & dosage, Globins pharmacology, Hematopoiesis, Extramedullary drug effects, Hematopoietic Stem Cell Transplantation, Hematopoietic Stem Cells, Humans, Iron Overload therapy, Mice, Recombinant Fusion Proteins biosynthesis, Recombinant Fusion Proteins blood, Recombinant Fusion Proteins pharmacology, Splenomegaly drug therapy, Splenomegaly pathology, Transduction, Genetic, beta-Thalassemia complications, Genetic Therapy methods, Globins genetics, beta-Thalassemia therapy
- Abstract
The beta-thalassemias are caused by more than 200 mutations that reduce or abolish beta-globin production. The severity of the resulting anemia can lead to lifelong transfusion dependency. A genetic treatment based on globin gene transfer would require that transgene expression be erythroid specific, elevated, and sustained over time. We report here that long-term synthesis of chimeric hemoglobin (mualpha(2):hubeta(A)(2)) could be achieved in mice with beta-thalassemia intermedia following engraftment with bone marrow cells transduced with a lentiviral vector encoding the human beta-globin gene. In the absence of any posttransduction selection, the treated chimeras exhibit durably increased hemoglobin levels without diminution over 40 weeks. Ineffective erythropoiesis and extramedullary hematopoiesis (EMH) regress, as reflected by normalization of spleen size, architecture, hematopoietic colony formation, and disappearance of liver EMH. These findings establish that a sustained increase of 3 to 4 g/dL hemoglobin is sufficient to correct ineffective erythropoiesis. Hepatic iron accumulation is markedly decreased in 1-year-old chimeras, indicating persistent protection from secondary organ damage. These results demonstrate for the first time that viral-mediated globin gene transfer in hematopoietic stem cells effectively treats a severe hemoglobin disorder.
- Published
- 2002
- Full Text
- View/download PDF
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