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Shekhar S, Liu Y, Wang S, Zhang H, Fang X, Zhang J, Fan L, Zheng B, Roman RJ, Wang Z, Fan F, Booz GW. Novel Mechanistic Insights and Potential Therapeutic Impact of TRPC6 in Neurovascular Coupling and Ischemic Stroke. Int J Mol Sci 2021; 22:2074. [PMID: 33669830 PMCID: PMC7922996 DOI: 10.3390/ijms22042074] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 02/12/2021] [Accepted: 02/17/2021] [Indexed: 12/13/2022] Open
Abstract
Ischemic stroke is one of the most disabling diseases and a leading cause of death globally. Despite advances in medical care, the global burden of stroke continues to grow, as no effective treatments to limit or reverse ischemic injury to the brain are available. However, recent preclinical findings have revealed the potential role of transient receptor potential cation 6 (TRPC6) channels as endogenous protectors of neuronal tissue. Activating TRPC6 in various cerebral ischemia models has been found to prevent neuronal death, whereas blocking TRPC6 enhances sensitivity to ischemia. Evidence has shown that Ca2+ influx through TRPC6 activates the cAMP (adenosine 3',5'-cyclic monophosphate) response element-binding protein (CREB), an important transcription factor linked to neuronal survival. Additionally, TRPC6 activation may counter excitotoxic damage resulting from glutamate release by attenuating the activity of N-methyl-d-aspartate (NMDA) receptors of neurons by posttranslational means. Unresolved though, are the roles of TRPC6 channels in non-neuronal cells, such as astrocytes and endothelial cells. Moreover, TRPC6 channels may have detrimental effects on the blood-brain barrier, although their exact role in neurovascular coupling requires further investigation. This review discusses evidence-based cell-specific aspects of TRPC6 in the brain to assess the potential targets for ischemic stroke management.
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Affiliation(s)
- Shashank Shekhar
- Department of Neurology, University of Mississippi Medical Center, Jackson, MS 39216, USA
| | - Yedan Liu
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, MS 39216, USA; (Y.L.); (S.W.); (H.Z.); (X.F.); (J.Z.); (L.F.); (B.Z.); (R.J.R.); (F.F.); (G.W.B.)
| | - Shaoxun Wang
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, MS 39216, USA; (Y.L.); (S.W.); (H.Z.); (X.F.); (J.Z.); (L.F.); (B.Z.); (R.J.R.); (F.F.); (G.W.B.)
| | - Huawei Zhang
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, MS 39216, USA; (Y.L.); (S.W.); (H.Z.); (X.F.); (J.Z.); (L.F.); (B.Z.); (R.J.R.); (F.F.); (G.W.B.)
| | - Xing Fang
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, MS 39216, USA; (Y.L.); (S.W.); (H.Z.); (X.F.); (J.Z.); (L.F.); (B.Z.); (R.J.R.); (F.F.); (G.W.B.)
| | - Jin Zhang
- School of Medicine, I.M. Sechenov First Moscow State Medical University, Moscow 119048, Russia
| | - Letao Fan
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, MS 39216, USA; (Y.L.); (S.W.); (H.Z.); (X.F.); (J.Z.); (L.F.); (B.Z.); (R.J.R.); (F.F.); (G.W.B.)
| | - Baoying Zheng
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, MS 39216, USA; (Y.L.); (S.W.); (H.Z.); (X.F.); (J.Z.); (L.F.); (B.Z.); (R.J.R.); (F.F.); (G.W.B.)
| | - Richard J. Roman
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, MS 39216, USA; (Y.L.); (S.W.); (H.Z.); (X.F.); (J.Z.); (L.F.); (B.Z.); (R.J.R.); (F.F.); (G.W.B.)
| | - Zhen Wang
- Department of Physiology and Biophysics, University of Mississippi Medical Center, Jackson, MS 39216, USA;
| | - Fan Fan
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, MS 39216, USA; (Y.L.); (S.W.); (H.Z.); (X.F.); (J.Z.); (L.F.); (B.Z.); (R.J.R.); (F.F.); (G.W.B.)
| | - George W. Booz
- Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, MS 39216, USA; (Y.L.); (S.W.); (H.Z.); (X.F.); (J.Z.); (L.F.); (B.Z.); (R.J.R.); (F.F.); (G.W.B.)
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2
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Matrix Mechanosensation in the Erythroid and Megakaryocytic Lineages. Cells 2020; 9:cells9040894. [PMID: 32268541 PMCID: PMC7226728 DOI: 10.3390/cells9040894] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 03/30/2020] [Accepted: 04/02/2020] [Indexed: 12/21/2022] Open
Abstract
The biomechanical properties of the bone marrow microenvironment emerge from a combination of interactions between various extracellular matrix (ECM) structural proteins and soluble factors. Matrix stiffness directs stem cell fate, and both bone marrow stromal and hematopoietic cells respond to biophysical cues. Within the bone marrow, the megakaryoblasts and erythroblasts are thought to originate from a common progenitor, giving rise to fully mature magakaryocytes (the platelet precursors) and erythrocytes. Erythroid and megakaryocytic progenitors sense and respond to the ECM through cell surface adhesion receptors such as integrins and mechanosensitive ion channels. While hematopoietic stem progenitor cells remain quiescent on stiffer ECM substrates, the maturation of the erythroid and megakaryocytic lineages occurs on softer ECM substrates. This review surveys the major matrix structural proteins that contribute to the overall biomechanical tone of the bone marrow, as well as key integrins and mechanosensitive ion channels identified as ECM sensors in context of megakaryocytosis or erythropoiesis.
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Kaestner L, Bogdanova A, Egee S. Calcium Channels and Calcium-Regulated Channels in Human Red Blood Cells. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1131:625-648. [PMID: 31646528 DOI: 10.1007/978-3-030-12457-1_25] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Free Calcium (Ca2+) is an important and universal signalling entity in all cells, red blood cells included. Although mature mammalian red blood cells are believed to not contain organelles as Ca2+ stores such as the endoplasmic reticulum or mitochondria, a 20,000-fold gradient based on a intracellular Ca2+ concentration of approximately 60 nM vs. an extracellular concentration of 1.2 mM makes Ca2+-permeable channels a major signalling tool of red blood cells. However, the internal Ca2+ concentration is tightly controlled, regulated and maintained primarily by the Ca2+ pumps PMCA1 and PMCA4. Within the last two decades it became evident that an increased intracellular Ca2+ is associated with red blood cell clearance in the spleen and promotes red blood cell aggregability and clot formation. In contrast to this rather uncontrolled deadly Ca2+ signals only recently it became evident, that a temporal increase in intracellular Ca2+ can also have positive effects such as the modulation of the red blood cells O2 binding properties or even be vital for brief transient cellular volume adaptation when passing constrictions like small capillaries or slits in the spleen. Here we give an overview of Ca2+ channels and Ca2+-regulated channels in red blood cells, namely the Gárdos channel, the non-selective voltage dependent cation channel, Piezo1, the NMDA receptor, VDAC, TRPC channels, CaV2.1, a Ca2+-inhibited channel novel to red blood cells and i.a. relate these channels to the molecular unknown sickle cell disease conductance Psickle. Particular attention is given to correlation of functional measurements with molecular entities as well as the physiological and pathophysiological function of these channels. This view is in constant progress and in particular the understanding of the interaction of several ion channels in a physiological context just started. This includes on the one hand channelopathies, where a mutation of the ion channel is the direct cause of the disease, like Hereditary Xerocytosis and the Gárdos Channelopathy. On the other hand it applies to red blood cell related diseases where an altered channel activity is a secondary effect like in sickle cell disease or thalassemia. Also these secondary effects should receive medical and pharmacologic attention because they can be crucial when it comes to the life-threatening symptoms of the disease.
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Affiliation(s)
- Lars Kaestner
- Theoretical Medicine and Biosciences, Saarland University, Homburg, Germany. .,Experimental Physics, Saarland University, Saarbrücken, Germany.
| | - Anna Bogdanova
- Red Blood Cell Research Group, Institute of Veterinary Physiology, Vetsuisse Faculty and the Zürich Center for Integrative Human Physiology (ZIHP), University of Zürich, Zürich, Switzerland
| | - Stephane Egee
- CNRS, UMR8227 LBI2M, Sorbonne Université, Roscoff, France.,Laboratoire d'Excellence GR-Ex, Paris, France
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4
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Liu MY, Hua WK, Chiou YY, Chen CJ, Yao CL, Lai YT, Lin CH, Lin WJ. Calcium-dependent methylation by PRMT1 promotes erythroid differentiation through the p38α MAPK pathway. FEBS Lett 2019; 594:301-316. [PMID: 31541584 DOI: 10.1002/1873-3468.13614] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Revised: 09/04/2019] [Accepted: 09/05/2019] [Indexed: 12/12/2022]
Abstract
Protein arginine methyltransferase 1 (PRMT1) stimulates erythroid differentiation, but the signaling events upstream are yet to be identified. Ca2+ plays crucial roles during erythroid differentiation. Here, we show that Ca2+ enhances methylation during induced erythroid differentiation and that Ca2+ directly upregulates the catalytic activity of recombinant PRMT1 by increasing Vmax toward the substrate heterogeneous nuclear ribonucleoprotein A2. We demonstrate that PRMT1 is essential and responsible for the effect of Ca2+ on differentiation. Depletion of Ca2+ suppresses PRMT1-mediated activation of p38α and p38α-stimulated differentiation. Furthermore, Ca2+ stimulates methylation of p38α by PRMT1. This study uncovers a novel regulatory mechanism for PRMT1 by Ca2+ and identifies the PRMT1/p38α axis as an intracellular mediator of Ca2+ signaling during erythroid differentiation.
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Affiliation(s)
- Mei-Yin Liu
- Institute of Biopharmaceutical Sciences, National Yang-Ming University, Taipei, Taiwan
| | - Wei-Kai Hua
- Institute of Biopharmaceutical Sciences, National Yang-Ming University, Taipei, Taiwan
| | - Yi-Ying Chiou
- Institute of Biopharmaceutical Sciences, National Yang-Ming University, Taipei, Taiwan
| | - Chi-Ju Chen
- Institute of Microbiology and Immunology, National Yang-Ming University, Taipei, Taiwan
| | - Chao-Ling Yao
- Department of Chemical Engineering and Materials Science, Yuan Ze University, Taoyuan, Taiwan
| | - Yi-Ting Lai
- Department of Chemical Engineering and Materials Science, Yuan Ze University, Taoyuan, Taiwan
| | - Chao-Hsiung Lin
- Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei, Taiwan
| | - Wey-Jinq Lin
- Institute of Biopharmaceutical Sciences, National Yang-Ming University, Taipei, Taiwan
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5
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Riehle M, Tsvetkov D, Gohlke BO, Preissner R, Harteneck C, Gollasch M, Nürnberg B. Molecular basis for the sensitivity of TRP channels to polyunsaturated fatty acids. NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 2018; 391:833-846. [PMID: 29736621 PMCID: PMC6061713 DOI: 10.1007/s00210-018-1507-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Accepted: 04/17/2018] [Indexed: 11/29/2022]
Abstract
Transient receptor potential (TRP) channels represent a superfamily of unselective cation channels that are subdivided into seven subfamilies based on their sequence homology and differences in gating and functional properties. Little is known about the molecular mechanisms of TRP channel regulation, particularly of the “canonical” TRP (TRPC) subfamily and their activation by polyunsaturated fatty acids (PUFAs). Here, we analyzed the structure-function relationship of Drosophila fruit fly TRPC channels. The primary aim was to uncover the molecular basis of PUFA sensitivity of Drosophila TRP-like (TRPL) and TRPgamma channels. Amino acid (aa) sequence alignment of the three Drosophila TRPC channels revealed 50 aa residues highly conserved in PUFA-sensitive TRPL and TRPgamma channels but not in the PUFA-insensitive TRP channel. Substitution of respective aa in TRPL by corresponding aa of TRP identified 18 residues that are necessary for PUFA-mediated activation of TRPL. Most aa positions are located within a stretch comprising transmembrane domains S2–S4, whereas six aa positions have been assigned to the proximal cytosolic C-terminus. Interestingly, residues I465 and S471 are required for activation by 5,8,11,14-eicosatetraynoic acid (ETYA) but not 5,8,11-eicosatriynoic acid (ETI). As proof of concept, we generated a PUFA-sensitive TRP channel by exchanging the corresponding aa from TRPL to TRP. Our study demonstrates a specific aa pattern in the transmembrane domains S2–S4 and the proximal C-terminus essential for TRP channel activation by PUFAs.
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Affiliation(s)
- Marc Riehle
- Department of Pharmacology and Experimental Therapy, Institute of Experimental and Clinical Pharmacology and Toxicology, Eberhard Karls University Hospitals and Clinics and Interfaculty Center of Pharmacogenomics and Drug Research (ICePhA), Wilhelmstrasse 56, 72074, Tübingen, Germany
| | - Dmitry Tsvetkov
- Department of Pharmacology and Experimental Therapy, Institute of Experimental and Clinical Pharmacology and Toxicology, Eberhard Karls University Hospitals and Clinics and Interfaculty Center of Pharmacogenomics and Drug Research (ICePhA), Wilhelmstrasse 56, 72074, Tübingen, Germany.,Experimental and Clinical Research Center (ECRC), a joint cooperation of the Charité University Medicine and Max Delbruck Center for Molecular Medicine in the Helmholtz Association, Lindenberger Weg 80, 13125, Berlin, Germany.,Medical Clinic for Nephrology and Internal Intensive Care, Charité Campus Virchow Klinikum, Berlin, Germany
| | - Björn-Oliver Gohlke
- Structural Bioinformatics Group, Institute for Physiology, Charité - University Medicine Berlin, Berlin, Germany
| | - Robert Preissner
- Structural Bioinformatics Group, Institute for Physiology, Charité - University Medicine Berlin, Berlin, Germany
| | - Christian Harteneck
- Department of Pharmacology and Experimental Therapy, Institute of Experimental and Clinical Pharmacology and Toxicology, Eberhard Karls University Hospitals and Clinics and Interfaculty Center of Pharmacogenomics and Drug Research (ICePhA), Wilhelmstrasse 56, 72074, Tübingen, Germany
| | - Maik Gollasch
- Experimental and Clinical Research Center (ECRC), a joint cooperation of the Charité University Medicine and Max Delbruck Center for Molecular Medicine in the Helmholtz Association, Lindenberger Weg 80, 13125, Berlin, Germany. .,Medical Clinic for Nephrology and Internal Intensive Care, Charité Campus Virchow Klinikum, Berlin, Germany.
| | - Bernd Nürnberg
- Department of Pharmacology and Experimental Therapy, Institute of Experimental and Clinical Pharmacology and Toxicology, Eberhard Karls University Hospitals and Clinics and Interfaculty Center of Pharmacogenomics and Drug Research (ICePhA), Wilhelmstrasse 56, 72074, Tübingen, Germany.
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6
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Yamaguchi Y, Iribe G, Kaneko T, Takahashi K, Numaga-Tomita T, Nishida M, Birnbaumer L, Naruse K. TRPC3 participates in angiotensin II type 1 receptor-dependent stress-induced slow increase in intracellular Ca 2+ concentration in mouse cardiomyocytes. J Physiol Sci 2018; 68:153-164. [PMID: 28105583 PMCID: PMC10718017 DOI: 10.1007/s12576-016-0519-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Accepted: 12/26/2016] [Indexed: 11/26/2022]
Abstract
When a cardiac muscle is held in a stretched position, its [Ca2+] transient increases slowly over several minutes in a process known as stress-induced slow increase in intracellular Ca2+ concentration ([Ca2+]i) (SSC). Transient receptor potential canonical (TRPC) 3 forms a non-selective cation channel regulated by the angiotensin II type 1 receptor (AT1R). In this study, we investigated the role of TRPC3 in the SSC. Isolated mouse ventricular myocytes were electrically stimulated and subjected to sustained stretch. An AT1R blocker, a phospholipase C inhibitor, and a TRPC3 inhibitor suppressed the SSC. These inhibitors also abolished the observed SSC-like slow increase in [Ca2+]i induced by angiotensin II, instead of stretch. Furthermore, the SSC was not observed in TRPC3 knockout mice. Simulation and immunohistochemical studies suggest that sarcolemmal TRPC3 is responsible for the SSC. These results indicate that sarcolemmal TRPC3, regulated by AT1R, causes the SSC.
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Affiliation(s)
- Yohei Yamaguchi
- Department of Cardiovascular Physiology, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University, Okayama, 700-8558, Japan
| | - Gentaro Iribe
- Department of Cardiovascular Physiology, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University, Okayama, 700-8558, Japan.
| | - Toshiyuki Kaneko
- Department of Physiology, Asahikawa Medical University, Asahikawa, Hokkaido, 078-8510, Japan
| | - Ken Takahashi
- Department of Cardiovascular Physiology, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University, Okayama, 700-8558, Japan
| | - Takuro Numaga-Tomita
- Division of Cardiocirculatory Signaling, Okazaki Institute for Integrative Bioscience (National Institute for Physiological Sciences), National Institutes of Natural Sciences, Okazaki, Aichi, 444-8787, Japan
| | - Motohiro Nishida
- Division of Cardiocirculatory Signaling, Okazaki Institute for Integrative Bioscience (National Institute for Physiological Sciences), National Institutes of Natural Sciences, Okazaki, Aichi, 444-8787, Japan
| | - Lutz Birnbaumer
- Neurobiology Laboratory, National Institute of Environmental Health Science, Research Triangle Park, NC, 27709, USA
| | - Keiji Naruse
- Department of Cardiovascular Physiology, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University, Okayama, 700-8558, Japan
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7
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Sukumaran P, Sun Y, Schaar A, Selvaraj S, Singh BB. TRPC Channels and Parkinson's Disease. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 976:85-94. [PMID: 28508315 DOI: 10.1007/978-94-024-1088-4_8] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Parkinson's disease (PD) is a common neurodegenerative disorder, which involves degeneration of dopaminergic neurons that are present in the substantia nigra pars compacta (SNpc) region. Many factors have been identified that could lead to Parkinson's disease; however, almost all of them are directly or indirectly dependent on Ca2+ signaling. Importantly, though disturbances in Ca2+ homeostasis have been implicated in Parkinson's disease and other neuronal diseases, the identity of the calcium channel remains elusive. Members of the transient receptor potential canonical (TRPC) channel family have been identified as a new class of Ca2+ channels, and it could be anticipated that these channels could play important roles in neurodegenerative diseases, especially in PD. Thus, in this chapter we have entirely focused on TRPC channels and elucidated its role in PD.
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Affiliation(s)
- Pramod Sukumaran
- Department of Biomedical Sciences, School of Medicine and Health Sciences, University of North Dakota, Grand Forks, ND, 58201, USA
| | - Yuyang Sun
- Department of Biomedical Sciences, School of Medicine and Health Sciences, University of North Dakota, Grand Forks, ND, 58201, USA
| | - Anne Schaar
- Department of Biomedical Sciences, School of Medicine and Health Sciences, University of North Dakota, Grand Forks, ND, 58201, USA
| | - Senthil Selvaraj
- Department of Biomedical Sciences, School of Medicine and Health Sciences, University of North Dakota, Grand Forks, ND, 58201, USA
| | - Brij B Singh
- Department of Biomedical Sciences, School of Medicine and Health Sciences, University of North Dakota, Grand Forks, ND, 58201, USA.
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8
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Ramanathan G, Mannhalter C. Increased expression of transient receptor potential canonical 6 (TRPC6) in differentiating human megakaryocytes. Cell Biol Int 2016; 40:223-31. [PMID: 26514329 DOI: 10.1002/cbin.10558] [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: 06/19/2015] [Accepted: 10/28/2015] [Indexed: 12/22/2022]
Abstract
Members of the transient receptor potential (TRP) family of cation conducting channels are found in several tissues and cell types where they have different physiological functions. The canonical TRP channel 6 (TRPC6) is present on the platelet membrane and appears to participate in calcium influx during platelet activation. However, limited information is available on the importance of TRPC channels in megakaryocytes (MKs), the precursor cells of platelets. We determined the mRNA and protein expression of TRPC family members and investigated the role of TRPC6 for proliferation and differentiation of human MKs derived from CD34+ progenitor cells. TRPC6 transcripts were highly expressed during the differentiation of MKs and TRPC6 protein was detectable in MK cytoplasm by confocal staining. TRPC6 channel activity was modulated by pharmacological approaches using flufenamic acid (FFA) for activation and SKF96365 for inhibition. Upon FFA stimulation in MKs, an increase in intracellular calcium was observed, which was blocked by SKF96365 at 10 µM concentration. Incubation of MKs with SKF96365 resulted in a reduction in thrombopoietin-stimulated cell proliferation. Our results suggest a role of TRPC6 in calcium homeostasis during MK development, particularly for cell proliferation.
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Affiliation(s)
| | - Christine Mannhalter
- Department of Laboratory Medicine, Medical University of Vienna, Vienna, Austria
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9
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Bouron A, Chauvet S, Dryer S, Rosado JA. Second Messenger-Operated Calcium Entry Through TRPC6. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 898:201-49. [PMID: 27161231 DOI: 10.1007/978-3-319-26974-0_10] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Canonical transient receptor potential 6 (TRPC6) proteins assemble into heteromultimeric structures forming non-selective cation channels. In addition, many TRPC6-interacting proteins have been identified like some enzymes, channels, pumps, cytoskeleton-associated proteins, immunophilins, or cholesterol-binding proteins, indicating that TRPC6 are engaged into macromolecular complexes. Depending on the cell type and the experimental conditions used, TRPC6 activity has been reported to be controlled by diverse modalities. For instance, the second messenger diacylglycerol, store-depletion, the plant extract hyperforin or H2O2 have all been shown to trigger the opening of TRPC6 channels. A well-characterized consequence of TRPC6 activation is the elevation of the cytosolic concentration of Ca(2+). This latter response can reflect the entry of Ca(2+) through open TRPC6 channels but it can also be due to the Na(+)/Ca(2+) exchanger (operating in its reverse mode) or voltage-gated Ca(2+) channels (recruited in response to a TRPC6-mediated depolarization). Although TRPC6 controls a diverse array of biological functions in many tissues and cell types, its pathophysiological functions are far from being fully understood. This chapter covers some key features of TRPC6, with a special emphasis on their biological significance in kidney and blood cells.
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Affiliation(s)
- Alexandre Bouron
- Université Grenoble Alpes, 38000, Grenoble, France. .,CNRS, iRTSV-LCBM, 38000, Grenoble, France.
| | - Sylvain Chauvet
- Université Grenoble Alpes, 38000, Grenoble, France.,CNRS, iRTSV-LCBM, 38000, Grenoble, France
| | - Stuart Dryer
- University of Houston, Houston, TX, USA.,Baylor College of Medicine, Houston, TX, USA
| | - Juan A Rosado
- Departamento de Fisiología, University of Extremadura, Cáceres, Spain
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10
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Ong HL, Ambudkar IS. Molecular determinants of TRPC1 regulation within ER–PM junctions. Cell Calcium 2015; 58:376-86. [DOI: 10.1016/j.ceca.2015.03.008] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2015] [Revised: 03/18/2015] [Accepted: 03/19/2015] [Indexed: 11/30/2022]
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11
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Ong HL, de Souza LB, Cheng KT, Ambudkar IS. Physiological functions and regulation of TRPC channels. Handb Exp Pharmacol 2014; 223:1005-34. [PMID: 24961978 DOI: 10.1007/978-3-319-05161-1_12] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The TRP-canonical (TRPC) subfamily, which consists of seven members (TRPC1-TRPC7), are Ca(2+)-permeable cation channels that are activated in response to receptor-mediated PIP2 hydrolysis via store-dependent and store-independent mechanisms. These channels are involved in a variety of physiological functions in different cell types and tissues. Of these, TRPC6 has been linked to a channelopathy resulting in human disease. Two key players of the store-dependent regulatory pathway, STIM1 and Orai1, interact with some TRPC channels to gate and regulate channel activity. The Ca(2+) influx mediated by TRPC channels generates distinct intracellular Ca(2+) signals that regulate downstream signaling events and consequent cell functions. This requires localization of TRPC channels in specific plasma membrane microdomains and precise regulation of channel function which is coordinated by various scaffolding, trafficking, and regulatory proteins.
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Affiliation(s)
- Hwei Ling Ong
- Secretory Physiology Section, Molecular Physiology and Therapeutics Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, 20892, USA
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12
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Makhro A, Hänggi P, Goede JS, Wang J, Brüggemann A, Gassmann M, Schmugge M, Kaestner L, Speer O, Bogdanova A. N-methyl-D-aspartate receptors in human erythroid precursor cells and in circulating red blood cells contribute to the intracellular calcium regulation. Am J Physiol Cell Physiol 2013; 305:C1123-38. [PMID: 24048732 DOI: 10.1152/ajpcell.00031.2013] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The presence of N-methyl-d-aspartate receptor (NMDAR) was previously shown in rat red blood cells (RBCs) and in a UT-7/Epo human myeloid cell line differentiating into erythroid lineage. Here we have characterized the subunit composition of the NMDAR and monitored its function during human erythropoiesis and in circulating RBCs. Expression of the NMDARs subunits was assessed in erythroid progenitors during ex vivo erythropoiesis and in circulating human RBCs using quantitative PCR and flow cytometry. Receptor activity was monitored using a radiolabeled antagonist binding assay, live imaging of Ca(2+) uptake, patch clamp, and monitoring of cell volume changes. The receptor tetramers in erythroid precursor cells are composed of the NR1, NR2A, 2C, 2D, NR3A, and 3B subunits of which the glycine-binding NR3A and 3B and glutamate-binding NR2C and 2D subunits prevailed. Functional receptor is required for survival of erythroid precursors. Circulating RBCs retain a low number of the receptor copies that is higher in young cells compared with mature and senescent RBC populations. In circulating RBCs the receptor activity is controlled by plasma glutamate and glycine. Modulation of the NMDAR activity in RBCs by agonists or antagonists is associated with the alterations in whole cell ion currents. Activation of the receptor results in the transient Ca(2+) accumulation, cell shrinkage, and alteration in the intracellular pH, which is associated with the change in hemoglobin oxygen affinity. Thus functional NMDARs are present in erythroid precursor cells and in circulating RBCs. These receptors contribute to intracellular Ca(2+) homeostasis and modulate oxygen delivery to peripheral tissues.
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Affiliation(s)
- Asya Makhro
- Institute of Veterinary Physiology, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
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13
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Ma YL, Rees DC, Gibson JS, Ellory JC. The conductance of red blood cells from sickle cell patients: ion selectivity and inhibitors. J Physiol 2012; 590:2095-105. [PMID: 22411011 DOI: 10.1113/jphysiol.2012.229609] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
The abnormally high cation permeability in red blood cells (RBCs) from patients with sickle cell disease (SCD) occupies a central role in pathogenesis. Sickle RBC properties are notably heterogeneous, however, thus limiting conventional flux techniques that necessarily average out the behaviour of millions of cells. Here we use the whole-cell patch configuration to characterise the permeability of single RBCs from patients with SCD in more detail. A non-specific cation conductance was reversibly induced upon deoxygenation and was permeable to both univalent (Na+, K+, Rb+) and also divalent (Ca2+, Mg2+) cations. It was sensitive to the tarantula spider toxin GsMTx-4. Mn2+ caused partial, reversible inhibition. The aromatic aldehyde o-vanillin also irreversibly inhibited the deoxygenation-induced conductance, partially at 1mM and almost completely at 5mM. Nifedipine, amiloride and ethylisopropylamiloride were ineffective. In oxygenated RBCs, the current was pH sensitive showing a marked increase as pH fell from 7.4 to 6, with no change apparent when pH was raised from 7.4 to 8. The effects of acidification and deoxygenation together were not additive. Many features of this deoxygenation-induced conductance (non-specificity for cations, permeability toCa2+ andMg2+, pH sensitivity, reversibility, partial inhibition by DIDS and Mn2+) are shared with the flux pathway sometimes referred to as Psickle. Sensitivity to GsMTx-4 indicates its possible identity as a stretch-activated channel. Sensitivity to o-vanillin implies that activation requires HbS polymerisation but since the conductance was observed in whole-cell patches, results suggest that bulk intracellular Hb is not involved; rather a membrane-bound subfraction is responsible for channel activation. The ability to record P(sickle)-like activity in single RBCs will facilitate further studies and eventual molecular identification of the pathway involved.
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Affiliation(s)
- Y-L Ma
- Department of Physiology, Anatomy & Genetics, Oxford, UK
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14
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Coulon S, Dussiot M, Grapton D, Maciel TT, Wang PHM, Callens C, Tiwari MK, Agarwal S, Fricot A, Vandekerckhove J, Tamouza H, Zermati Y, Ribeil JA, Djedaini K, Oruc Z, Pascal V, Courtois G, Arnulf B, Alyanakian MA, Mayeux P, Leanderson T, Benhamou M, Cogné M, Monteiro RC, Hermine O, Moura IC. Polymeric IgA1 controls erythroblast proliferation and accelerates erythropoiesis recovery in anemia. Nat Med 2011; 17:1456-65. [PMID: 22019886 DOI: 10.1038/nm.2462] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2011] [Accepted: 08/04/2011] [Indexed: 01/04/2023]
Abstract
Anemia because of insufficient production of and/or response to erythropoietin (Epo) is a major complication of chronic kidney disease and cancer. The mechanisms modulating the sensitivity of erythroblasts to Epo remain poorly understood. We show that, when cultured with Epo at suboptimal concentrations, the growth and clonogenic potential of erythroblasts was rescued by transferrin receptor 1 (TfR1)-bound polymeric IgA1 (pIgA1). Under homeostatic conditions, erythroblast numbers were increased in mice expressing human IgA1 compared to control mice. Hypoxic stress of these mice led to increased amounts of pIgA1 and erythroblast expansion. Expression of human IgA1 or treatment of wild-type mice with the TfR1 ligands pIgA1 or iron-loaded transferrin (Fe-Tf) accelerated recovery from acute anemia. TfR1 engagement by either pIgA1 or Fe-Tf increased cell sensitivity to Epo by inducing activation of mitogen-activated protein kinase (MAPK) and phosphatidylinositol 3-kinase (PI3K) signaling pathways. These cellular responses were mediated through the TfR1-internalization motif, YXXΦ. Our results show that pIgA1 and TfR1 are positive regulators of erythropoiesis in both physiological and pathological situations. Targeting this pathway may provide alternate approaches to the treatment of ineffective erythropoiesis and anemia.
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Affiliation(s)
- Séverine Coulon
- Centre National de la Recherche Scientifique (CNRS) Unité Mixte Recherche (UMR) 8147, Université Paris Descartes, Faculté de Médecine, Hôpital Necker, Paris, France
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15
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Hirschler-Laszkiewicz I, Zhang W, Keefer K, Conrad K, Tong Q, Chen SJ, Bronson S, Cheung JY, Miller BA. Trpc2 depletion protects red blood cells from oxidative stress-induced hemolysis. Exp Hematol 2011; 40:71-83. [PMID: 21924222 DOI: 10.1016/j.exphem.2011.09.006] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2011] [Revised: 08/22/2011] [Accepted: 09/09/2011] [Indexed: 11/29/2022]
Abstract
Transient receptor potential (TRP) channels Trpc2 and Trpc3 are expressed on normal murine erythroid precursors, and erythropoietin stimulates an increase in intracellular calcium ([Ca(2+)](i)) through TRPC2 and TRPC3. Because modulation of [Ca(2+)](i) is an important signaling pathway in erythroid proliferation and differentiation, Trpc2, Trpc3, and Trpc2/Trpc3 double knockout mice were utilized to explore the roles of these channels in erythropoiesis. Trpc2, Trpc3, and Trpc2/Trpc3 double knockout mice were not anemic, and had similar red blood cell counts, hemoglobins, and reticulocyte counts as wild-type littermate controls. Although the erythropoietin-induced increase in [Ca(2+)](i) was reduced, these knockout mice showed no defects in red cell production. The major phenotypic difference at steady state was that the mean corpuscular volume, mean corpuscular hemoglobin, and hematocrit of red cells were significantly greater in Trpc2 and Trpc2/Trpc3 double knockout mice, and mean corpuscular hemoglobin concentration was significantly reduced. All hematological parameters in Trpc3 knockout mice were similar to controls. When exposed to phenylhydrazine, unlike the Trpc3 knockouts, Trpc2 and Trpc2/Trpc3 double knockout mice showed significant resistance to hemolysis. This was associated with a significant reduction in hydrogen peroxide-induced calcium influx in erythroblasts. Although erythropoietin-induced calcium influx through TRPC2 or TRPC3 is not critical for erythroid production, these data demonstrate that TRPC2 plays an important role in oxidative stress-induced hemolysis, which may be related to reduced calcium entry in red cells in the presence of Trpc2 depletion.
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16
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Park KS, Pang B, Park SJ, Lee YG, Bae JY, Park S, Kim I, Kim SJ. Identification and functional characterization of ion channels in CD34(+) hematopoietic stem cells from human peripheral blood. Mol Cells 2011; 32:181-8. [PMID: 21638203 PMCID: PMC3887668 DOI: 10.1007/s10059-011-0068-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2011] [Revised: 05/16/2011] [Accepted: 05/23/2011] [Indexed: 02/06/2023] Open
Abstract
Hematopoietic stem cells (HSCs) are used therapeutically for hematological diseases and may also serve as a source for nonhematopoietic tissue engineering in the future. In other cell types, ion channels have been investigated as potential targets for the regulation of proliferation and differentiation. However, the ion channels of HSCs remain elusive. Here, we functionally characterized the ion channels of CD34(+) cells from human peripheral blood. Using fluorescence-activated cell sorting, we confirmed that the CD34(+) cells also express CD45 and CD133. In the CD34(+)/CD45(+)/CD133(high) HSCs, RT-PCR of 58 ion channel mRNAs revealed the coexpression of Kv1.3, Kv7.1, Nav1.7, TASK2, TALK2, TWIK2, TRPC4, TRPC6, TRPM2, TRPM7, and TRPV2. Whole-cell patch clamp recordings identified voltage-gated K(+) currents (putatively Kv1.3), pH-sensitive TASK2-like back-ground K(+) currents, ADP-ribose-activated TRPM2 currents, temperature-sensitive TRPV2-like currents, and diacylglycerol-analogue-activated TRPC6-like currents. Our results lend new insight into the physiological role of ion channels in HSCs, the specific implications of which require further investigation.
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Affiliation(s)
- Kyoung Sun Park
- Division of Integrative Biosciences and Biotechnology, Pohang University of Science and Technology, Pohang 790-784, Korea
- Ischemic/Hypoxic Disease Institute, Seoul 110-744, Korea
| | - Bo Pang
- Departments of Physiology, Seoul National University College of Medicine, Seoul 110-744, Korea
| | - Su Jung Park
- Departments of Physiology, Seoul National University College of Medicine, Seoul 110-744, Korea
| | - Yun-Gyoo Lee
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul 110-744, Korea
| | - Ji-Yeon Bae
- Diagnostic DNA Chip Center, The Ilchun Molecular Medicine Institute, Medical Research Center, Seoul National University, Seoul 110-744, Korea
| | - Seonyang Park
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul 110-744, Korea
- Diagnostic DNA Chip Center, The Ilchun Molecular Medicine Institute, Medical Research Center, Seoul National University, Seoul 110-744, Korea
- Cancer Research Institute, Seoul National University College of Medicine, Seoul 110-744, Korea
| | - Inho Kim
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul 110-744, Korea
- Diagnostic DNA Chip Center, The Ilchun Molecular Medicine Institute, Medical Research Center, Seoul National University, Seoul 110-744, Korea
- Cancer Research Institute, Seoul National University College of Medicine, Seoul 110-744, Korea
| | - Sung Joon Kim
- Ischemic/Hypoxic Disease Institute, Seoul 110-744, Korea
- Departments of Physiology, Seoul National University College of Medicine, Seoul 110-744, Korea
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17
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Hirschler-Laszkiewicz I, Tong Q, Waybill K, Conrad K, Keefer K, Zhang W, Chen SJ, Cheung JY, Miller BA. The transient receptor potential (TRP) channel TRPC3 TRP domain and AMP-activated protein kinase binding site are required for TRPC3 activation by erythropoietin. J Biol Chem 2011; 286:30636-30646. [PMID: 21757714 DOI: 10.1074/jbc.m111.238360] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Modulation of intracellular calcium ([Ca(2+)](i)) by erythropoietin (Epo) is an important signaling pathway controlling erythroid proliferation and differentiation. Transient receptor potential (TRP) channels TRPC3 and homologous TRPC6 are expressed on normal human erythroid precursors, but Epo stimulates an increase in [Ca(2+)](i) through TRPC3 but not TRPC6. Here, the role of specific domains in the different responsiveness of TRPC3 and TRPC6 to erythropoietin was explored. TRPC3 and TRPC6 TRP domains differ in seven amino acids. Substitution of five amino acids (DDKPS) in the TRPC3 TRP domain with those of TRPC6 (EERVN) abolished the Epo-stimulated increase in [Ca(2+)](i). Substitution of EERVN in TRPC6 TRP domain with DDKPS in TRPC3 did not confer Epo responsiveness. However, substitution of TRPC6 TRP with DDKPS from TRPC3 TRP, as well as swapping the TRPC6 distal C terminus (C2) with that of TRPC3, resulted in a chimeric TRPC6 channel with Epo responsiveness similar to TRPC3. Substitution of TRPC6 with TRPC3 TRP and the putative TRPC3 C-terminal AMP-activated protein kinase (AMPK) binding site straddling TRPC3 C1/C2 also resulted in TRPC6 activation. In contrast, substitution of the TRPC3 C-terminal leucine zipper motif or TRPC3 phosphorylation sites Ser-681, Ser-708, or Ser-764 with TRPC6 sequence did not affect TRPC3 Epo responsiveness. TRPC3, but not TRPC6, and TRPC6 chimeras expressing TRPC3 C2 showed significantly increased plasma membrane insertion following Epo stimulation and substantial cytoskeletal association. The TRPC3 TRP domain, distal C terminus (C2), and AMPK binding site are critical elements that confer Epo responsiveness. In particular, the TRPC3 C2 and AMPK site are essential for association of TRPC3 with the cytoskeleton and increased channel translocation to the cell surface in response to Epo stimulation.
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Affiliation(s)
| | - Qin Tong
- Departments of Pediatrics, Hershey, Pennsylvania 17033
| | | | | | - Kerry Keefer
- Departments of Pediatrics, Hershey, Pennsylvania 17033
| | - Wenyi Zhang
- Departments of Pediatrics, Hershey, Pennsylvania 17033
| | - Shu-Jen Chen
- Departments of Pediatrics, Hershey, Pennsylvania 17033
| | - Joseph Y Cheung
- Department of Medicine, Jefferson Medical College, Philadelphia, Pennsylvania 19107
| | - Barbara A Miller
- Departments of Pediatrics, Hershey, Pennsylvania 17033; Biochemistry and Molecular Biology, Pennsylvania State University College of Medicine, Hershey, Pennsylvania 17033.
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18
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Calcium as a mediator between erythropoietin and protein tyrosine phosphatase 1B. Arch Biochem Biophys 2011; 505:242-9. [DOI: 10.1016/j.abb.2010.10.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2010] [Revised: 09/28/2010] [Accepted: 10/02/2010] [Indexed: 01/09/2023]
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19
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Huang LJ, Shen YM, Bulut GB. Advances in understanding the pathogenesis of primary familial and congenital polycythaemia. Br J Haematol 2010; 148:844-52. [PMID: 20096014 DOI: 10.1111/j.1365-2141.2009.08069.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Primary familial and congenital polycythemia (PFCP) is an autosomal-dominant proliferative disorder characterized by erythrocytosis and hypersensitivity of erythroid progenitors to erythropoietin (Epo). Several lines of evidence suggest a causal role of truncated erythropoietin receptor (EpoR) in this disease. In this review, we discuss PFCP in the context of erythrocytosis and EpoR signalling. We focus on recent studies describing mechanisms underlying Epo-dependent EpoR down-regulation. One mechanism depends on internalization mediated through the p85 regulatory subunit of the Phosphoinositide 3-Kinase, and the other utilizes ubiquitin-based proteasomal degradation. Truncated PFCP EpoRs are not properly down-regulated upon stimulation, underscoring the importance of these mechanisms in the pathogenesis of PFCP.
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Affiliation(s)
- Lily J Huang
- Department of Cell Biology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390-9039, USA.
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20
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Migliaccio G, Sanchez M, Leblanc A, Masiello F, Tirelli V, Migliaccio AR, Najfeld V, Whitsett C. Long-term storage does not alter functionality of in vitro generated human erythroblasts: implications for ex vivo generated erythroid transfusion products. Transfusion 2009; 49:2668-79. [PMID: 19659677 DOI: 10.1111/j.1537-2995.2009.02329.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND Cultured human erythroid cells derived in vitro may represent alternative transfusion products. It is unknown, however, if these ex vivo expanded erythroid cells remain functional or develop genetic abnormalities after storage. STUDY DESIGN AND METHODS Using mononuclear cells from four adult blood donors, erythroblasts were generated ex vivo in expansion cultures supplemented with stem cell factor, interleukin-3, erythropoietin (EPO), dexamethasone, and estradiol. The viability and in vitro function of freshly expanded or short (1-2 months)- and long (8 years)-term-stored erythroblasts cryopreserved in dimethyl sulfoxide were compared. Erythroblast function was defined as ability to proliferate in expansion media and mature in response to EPO. Cell number was determined manually and expressed as fold increase. Viability was assessed by trypan blue and propidium iodide exclusion. Maturation was evaluated by morphologic analyses and CD36/CD235a expression profiling. Cytogenetic evaluation included karyotype and multicolor fluorescence in situ hybridization analyses. RESULTS Equivalent numbers (>80%) of erythroblasts were viable after short- and long-term storage. Freshly expanded and short- and long-term-stored erythroblasts equally doubled in number (fold increase, 2.4) retaining an immature phenotype (23% of the cells were CD36(high)CD235a(neg)) when cultured for 4 days under expansion conditions. The numbers of freshly expanded and short-term-stored erythroblasts that matured when exposed for 4 days to EPO were also similar (approx. 22% of the cells became CD36(neg)CD235a(high)). In spite of the massive amplification, ex vivo generated erythroblasts demonstrated a normal (46,XY) karyotype with no obvious genomic rearrangements. CONCLUSION Ex vivo expanded erythroblasts remain functional and genetically normal after long-term storage.
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Affiliation(s)
- Giovanni Migliaccio
- Division of Hematology and Oncology, Tisch Cancer Institute, Mount Sinai School of Medicine, New York, New York, USA
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