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Rix B, Maduro AH, Bridge KS, Grey W. Markers for human haematopoietic stem cells: The disconnect between an identification marker and its function. Front Physiol 2022; 13:1009160. [PMID: 36246104 PMCID: PMC9564379 DOI: 10.3389/fphys.2022.1009160] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Accepted: 08/22/2022] [Indexed: 11/13/2022] Open
Abstract
The haematopoietic system is a classical stem cell hierarchy that maintains all the blood cells in the body. Haematopoietic stem cells (HSCs) are rare, highly potent cells that reside at the apex of this hierarchy and are historically some of the most well studied stem cells in humans and laboratory models, with haematopoiesis being the original system to define functional cell types by cell surface markers. Whilst it is possible to isolate HSCs to near purity, we know very little about the functional activity of markers to purify HSCs. This review will focus on the historical efforts to purify HSCs in humans based on cell surface markers, their putative functions and recent advances in finding functional markers on HSCs.
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Affiliation(s)
| | | | | | - William Grey
- *Correspondence: Katherine S. Bridge, ; William Grey,
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2
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Hofbauer TM, Mangold A, Scherz T, Seidl V, Panzenböck A, Ondracek AS, Müller J, Schneider M, Binder T, Hell L, Lang IM. Neutrophil extracellular traps and fibrocytes in ST-segment elevation myocardial infarction. Basic Res Cardiol 2019; 114:33. [PMID: 31312919 PMCID: PMC6647191 DOI: 10.1007/s00395-019-0740-3] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2019] [Accepted: 06/26/2019] [Indexed: 01/22/2023]
Abstract
Leukocyte-mediated inflammation is central in atherothrombosis and ST-segment elevation myocardial infarction (STEMI). Neutrophil extracellular traps (NETs) have been shown to enhance atherothrombosis and stimulate fibroblast function. We analyzed the effects of NETs on cardiac remodeling after STEMI. We measured double-stranded (ds)DNA and citrullinated histone H3 (citH3) as NET surrogate markers in human culprit site and femoral blood collected during primary percutaneous coronary intervention (n = 50). Fibrocytes were characterized in whole blood by flow cytometry, and in culprit site thrombi and myocardium by immunofluorescence. To investigate mechanisms of fibrocyte activation, isolated NETs were used to induce fibrocyte responses in vitro. Enzymatic infarct size was assessed using creatine-phosphokinase isoform MB area under the curve. Left ventricular function was measured by transthoracic echocardiography. NET surrogate markers were increased at the culprit site compared to the femoral site and were positively correlated with infarct size and left ventricular dysfunction at follow-up. In vitro, NETs promoted fibrocyte differentiation from monocytes and induced fibrocyte activation. Highly activated fibrocytes accumulated at the culprit site and in the infarct transition zone. Our data suggest that NETs might be important mediators of fibrotic remodeling after STEMI, possibly by stimulating fibrocytes.
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Affiliation(s)
- Thomas M Hofbauer
- Division of Cardiology, Department of Internal Medicine II, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
| | - Andreas Mangold
- Division of Cardiology, Department of Internal Medicine II, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
| | - Thomas Scherz
- Division of Cardiology, Department of Internal Medicine II, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
| | - Veronika Seidl
- Division of Cardiology, Department of Internal Medicine II, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
| | - Adelheid Panzenböck
- Division of Cardiology, Department of Internal Medicine II, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
| | - Anna S Ondracek
- Division of Cardiology, Department of Internal Medicine II, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
| | - Julian Müller
- Division of Cardiology, Department of Internal Medicine II, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
| | - Matthias Schneider
- Division of Cardiology, Department of Internal Medicine II, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
| | - Thomas Binder
- Division of Cardiology, Department of Internal Medicine II, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
| | - Lena Hell
- Division of Haematology and Haemostaseology, Department of Internal Medicine I, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria
| | - Irene M Lang
- Division of Cardiology, Department of Internal Medicine II, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria.
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Panyajai P, Tima S, Chiampanichayakul S, Anuchapreeda S. Dietary Turmeric Bisdemethoxycurcumin Suppresses Wilms’ Tumor 1 and CD34 Protein Expressions in KG-1a Leukemic Stem Cells. Nutr Cancer 2019; 71:1189-1200. [DOI: 10.1080/01635581.2019.1598565] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Pawaret Panyajai
- Division of Clinical Microscopy, Department of Medical Technology, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai, Thailand
| | - Singkome Tima
- Division of Clinical Microscopy, Department of Medical Technology, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai, Thailand
- Cancer Research Unit of Associated Medical Sciences (AMS-CRU), Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai, Thailand
- Center for Research and Development of Natural Products for Health, Chiang Mai University, Chiang Mai, Thailand
| | - Sawitree Chiampanichayakul
- Division of Clinical Microscopy, Department of Medical Technology, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai, Thailand
- Cancer Research Unit of Associated Medical Sciences (AMS-CRU), Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai, Thailand
| | - Songyot Anuchapreeda
- Division of Clinical Microscopy, Department of Medical Technology, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai, Thailand
- Cancer Research Unit of Associated Medical Sciences (AMS-CRU), Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai, Thailand
- Center for Research and Development of Natural Products for Health, Chiang Mai University, Chiang Mai, Thailand
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Schäck LM, Noack S, Weist R, Jagodzinski M, Krettek C, Buettner M, Hoffmann A. Analysis of Surface Protein Expression in Human Bone Marrow Stromal Cells: New Aspects of Culture-Induced Changes, Inter-Donor Differences and Intracellular Expression. Stem Cells Dev 2013; 22:3226-35. [DOI: 10.1089/scd.2013.0290] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Affiliation(s)
| | - Sandra Noack
- Department of Orthopaedic Trauma, Hannover Medical School, Hannover, Germany
| | - Ramona Weist
- Department of Orthopaedic Trauma, Hannover Medical School, Hannover, Germany
| | - Michael Jagodzinski
- Department of Orthopaedic Trauma, Hannover Medical School, Hannover, Germany
| | - Christian Krettek
- Department of Orthopaedic Trauma, Hannover Medical School, Hannover, Germany
| | - Manuela Buettner
- Institute for Functional and Applied Anatomy, Hannover Medical School, Hannover, Germany
| | - Andrea Hoffmann
- Department of Orthopaedic Trauma, Hannover Medical School, Hannover, Germany
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5
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Anagnostakis I, Papassavas AC, Michalopoulos E, Chatzistamatiou T, Andriopoulou S, Tsakris A, Stavropoulos-Giokas C. Successful short-term cryopreservation of volume-reduced cord blood units in a cryogenic mechanical freezer: effects on cell recovery, viability, and clonogenic potential. Transfusion 2013; 54:211-23. [DOI: 10.1111/trf.12239] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2012] [Revised: 03/28/2013] [Accepted: 04/02/2013] [Indexed: 12/13/2022]
Affiliation(s)
- Ioannis Anagnostakis
- Hellenic Cord Blood Bank; Foundation for Biomedical Research; Academy of Athens
- Department of Immunology and National Tissue Typing Center; “G. Gennimatas” General Hospital
- Department of Microbiology; Medical School; University of Athens; Athens Greece
| | - Andreas C. Papassavas
- Hellenic Cord Blood Bank; Foundation for Biomedical Research; Academy of Athens
- Department of Immunology and National Tissue Typing Center; “G. Gennimatas” General Hospital
- Department of Microbiology; Medical School; University of Athens; Athens Greece
| | - Efstathios Michalopoulos
- Hellenic Cord Blood Bank; Foundation for Biomedical Research; Academy of Athens
- Department of Immunology and National Tissue Typing Center; “G. Gennimatas” General Hospital
- Department of Microbiology; Medical School; University of Athens; Athens Greece
| | - Theofanis Chatzistamatiou
- Hellenic Cord Blood Bank; Foundation for Biomedical Research; Academy of Athens
- Department of Immunology and National Tissue Typing Center; “G. Gennimatas” General Hospital
- Department of Microbiology; Medical School; University of Athens; Athens Greece
| | - Sofia Andriopoulou
- Hellenic Cord Blood Bank; Foundation for Biomedical Research; Academy of Athens
- Department of Immunology and National Tissue Typing Center; “G. Gennimatas” General Hospital
- Department of Microbiology; Medical School; University of Athens; Athens Greece
| | - Athanassios Tsakris
- Hellenic Cord Blood Bank; Foundation for Biomedical Research; Academy of Athens
- Department of Immunology and National Tissue Typing Center; “G. Gennimatas” General Hospital
- Department of Microbiology; Medical School; University of Athens; Athens Greece
| | - Catherine Stavropoulos-Giokas
- Hellenic Cord Blood Bank; Foundation for Biomedical Research; Academy of Athens
- Department of Immunology and National Tissue Typing Center; “G. Gennimatas” General Hospital
- Department of Microbiology; Medical School; University of Athens; Athens Greece
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Deterding LJ, Williams JG, Humble MM, Petrovich RM, Wei SJ, Trempus CS, Gates MB, Zhu F, Smart RC, Tennant RW, Tomer KB. CD34 Antigen: Determination of Specific Sites of Phosphorylation In Vitro and In Vivo. INTERNATIONAL JOURNAL OF MASS SPECTROMETRY 2011; 301:12-21. [PMID: 21499536 PMCID: PMC3077033 DOI: 10.1016/j.ijms.2010.05.027] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
CD34, a type I transmembrane glycoprotein, is a surface antigen which is expressed on several cell types, including hematopoietic progenitors, endothelial cells, as well as mast cells. Recently, CD34 has been described as a marker for epidermal stem cells in mouse hair follicles, and is expressed in outer root sheath cells of the human hair follicle. Although the biological function and regulation of CD34 is not well understood, it is thought to be involved in cell adhesion as well as possibly having a role in signal transduction. In addition, CD34 was shown to be critical for skin tumor development in mice, although the exact mechanism remains unknown.Many proteins' functions and biological activities are regulated through post-translational modifications. The extracellular domain of CD34 is heavily glycosylated but the role of these glycans in CD34 function is unknown. Additionally, two sites of tyrosine phosphorylation have been reported on human CD34 and it is known that CD34 is phosphorylated, at least in part, by protein kinase C; however, the precise location of the sites of phosphorylation has not been reported. In an effort to identify specific phosphorylation sites in CD34 and delineate the possible role of protein kinase C, we undertook the identification of the in vitro sites of phosphorylation on the intracellular domain of mouse CD34 (aa 309-382) following PKC treatment. For this work, we are using a combination of enzymatic proteolysis and peptide sequencing by mass spectrometry. After which the in vivo sites of phosphorylation of full-length mouse CD34 expressed from HEK293F cells were determined. The observed in vivo sites of phosphorylation, however, are not consensus PKC sites, but our data indicate that one of these sites may possibly be phosphorylated by AKT2. These results suggest that other kinases, as well as PKC, may have important signaling functions in CD34.
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Affiliation(s)
- Leesa J. Deterding
- Laboratory of Structural Biology, National Institutes of Health, PO Box 12233, Research Triangle Park, NC 27709
| | - Jason G. Williams
- Laboratory of Structural Biology, National Institutes of Health, PO Box 12233, Research Triangle Park, NC 27709
| | - Margaret M. Humble
- Laboratory of Pharmacology and Toxicology, National Institute of Environmental Health Sciences, National Institutes of Health, PO Box 12233, Research Triangle Park, NC 27709
| | - Robert M. Petrovich
- Laboratory of Structural Biology, National Institutes of Health, PO Box 12233, Research Triangle Park, NC 27709
| | - Sung-Jen Wei
- Laboratory of Pharmacology and Toxicology, National Institute of Environmental Health Sciences, National Institutes of Health, PO Box 12233, Research Triangle Park, NC 27709
| | - Carol S. Trempus
- Laboratory of Pharmacology and Toxicology, National Institute of Environmental Health Sciences, National Institutes of Health, PO Box 12233, Research Triangle Park, NC 27709
| | - Matthew B. Gates
- Laboratory of Structural Biology, National Institutes of Health, PO Box 12233, Research Triangle Park, NC 27709
| | - Feng Zhu
- Cell Signaling and Cancer Group, Department of Environmental and Molecular Toxicology, North Carolina State University, Box 7633, Raleigh, NC 27695
| | - Robert C. Smart
- Cell Signaling and Cancer Group, Department of Environmental and Molecular Toxicology, North Carolina State University, Box 7633, Raleigh, NC 27695
| | - Raymond W. Tennant
- Laboratory of Pharmacology and Toxicology, National Institute of Environmental Health Sciences, National Institutes of Health, PO Box 12233, Research Triangle Park, NC 27709
| | - Kenneth B. Tomer
- Laboratory of Structural Biology, National Institutes of Health, PO Box 12233, Research Triangle Park, NC 27709
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Mouiseddine M, Mathieu N, Stefani J, Demarquay C, Bertho JM. Characterization and histological localization of multipotent mesenchymal stromal cells in the human postnatal thymus. Stem Cells Dev 2009; 17:1165-74. [PMID: 19006457 DOI: 10.1089/scd.2007.0252] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
The aim of this work was to characterize multipotent mesenchymal stromal cells (MSCs) in the postnatal human thymus and to localize these MSCs in the organ. Adherent cells isolated from thymus samples were characterized by cell-surface antigen expression. This showed that adherent cells have a MSC profile as assessed by the expression of CD73 and CD105 markers and the lack of CD45 expression. These cells are able to differentiate in vitro into adipocytes, osteoblasts, and chondrocytes and to inhibit mixed lymphocyte reaction. This indicates that isolated cells have all of the characteristics of MSC. The fibroblast colony-forming unit (CFU-F) assay was used to determine their frequency in the postnatal thymus. This frequency was 60.9 +/- 14.8 CFU-F per 1 x 10(5) freshly isolated mononuclear cells. Moreover, taking advantage of CD34 and CD105 expression, immunohistological staining allowed us to localize MSC within interlobular trabeculae in close contact with the outer cortex. Polymerase chain reaction experiments indicated that thymic MSC expressed interleukin-7 and stromal cell-derived factor-1 messenger RNA. Overall, these results confirm previous findings of the presence in the adult human thymus of multipotent MSCs with a phenotype similar to adipose-derived adult stem cells. These results also show for the first time a histological localization of MSC in an organ. This suggests a possible role of thymic MSC in intrathymic differentiation.
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Affiliation(s)
- Moubarak Mouiseddine
- Laboratoire de Thérapie Cellulaire et de Radioprotection Accidentelle, IRSN, Fontenay aux Roses, France
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8
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Gangenahalli GU, Singh VK, Verma YK, Gupta P, Sharma RK, Chandra R, Luthra PM. Hematopoietic stem cell antigen CD34: role in adhesion or homing. Stem Cells Dev 2006; 15:305-13. [PMID: 16846369 DOI: 10.1089/scd.2006.15.305] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
CD34 is highly glycosylated surface antigen of enormous clinical utility in the identification, enumeration, and purification of engraftable lymphohematopoietic progenitors for transplantation. However, recently its importance in the specific marking of most immature hematopoietic stem/progenitor cells have been questioned by addressing long-term reconstitution capability of CD34(-) hematopoietic cellular fractions. These controversies have stimulated a demand for elucidation of the structure, function, and molecular interactions of CD34 to define exactly its biological significance in clinical regimens. There is accumulating data showing the participation of CD34 in adhesion or perhaps homing of lymphohematopoietic progenitors. On the other hand, CD34 has been demonstrated to down-regulate cytokine-induced differentiation and proliferation of CD34(+) cells. Studies in CD34 knockout mice revealed normal hematopoiesis but a profound delay in hematopoietic reconstitution after sublethal irradiation of the mice. In short, CD34 expression is likely to represent a specific state of hematopoietic development that may have altered adhering properties with expanding and differentiating capabilities in both in vitro and in vivo conditions. This article focuses on the adhesive properties of CD34 and its potential role in homing, which are likely to mimic lymphocyte homing to the inflammatory sites.
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Affiliation(s)
- Gurudutta U Gangenahalli
- Stem-Cell Gene Therapy Research Group, Institute of Nuclear Medicine & Allied Sciences, Delhi, India.
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Brunet De La Grange P, Barthe C, Lippert E, Hermitte F, Belloc F, Lacombe F, Ivanovic Z, Praloran V. Oxygen concentration influences mRNA processing and expression of the cd34 gene. J Cell Biochem 2006; 97:135-44. [PMID: 16173076 DOI: 10.1002/jcb.20597] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
CD34 is a cell surface glycoprotein expressed on hematopoietic stem and progenitor cells that disappears with their maturation. This gene is transcribed in two alternatively spliced mRNAs that encode full length and truncated form of CD34 cell surface antigen. Some publications suggested that CD34 full length plays a role in the maintenance of their self renewal capacity. An examination of CD34 regulation by a low O2 concentration that ensures a better maintenance of stem cells may provide important insights into the molecular control of hematopoiesis. Using human cord blood CD34+ cells, we first compared the effect of short term (24 h) culture in hypoxia (1% O2) and normoxia (20% O2) on the expression of full length and truncated form of cd34 transcripts and on the expression of the CD34 antigen. Hypoxia maintained a larger quantity of cd34 full length transcripts and a higher cd34 full length/cd34 truncated form ratio than normoxia. After 72 h of culture at 1% and 20% O2, sorted CD34low sub-population from 1% O2 primary culture still contained more cd34 full length mRNAs than those from 20% O2, maintained better CD34 antigen expression during secondary culture at 20% O2 and contained more undifferentiated cells. This work provides the first evidence of the regulation of the cd34 gene by hypoxia resulting in a delayed higher and longer antigen expression by cord blood cells. We suggest that this phenomenon is related to the better maintenance of primitive stem cells in hypoxia.
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Tan PC, Furness SGB, Merkens H, Lin S, McCoy ML, Roskelley CD, Kast J, McNagny KM. Na+/H+ exchanger regulatory factor-1 is a hematopoietic ligand for a subset of the CD34 family of stem cell surface proteins. Stem Cells 2006; 24:1150-61. [PMID: 16410385 DOI: 10.1634/stemcells.2005-0426] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
CD34 and its relatives, podocalyxin and endoglycan, comprise a family of surface sialomucins expressed by hematopoietic stem/progenitor cells and vascular endothelia. Recent data suggest that they serve as either pro- or antiadhesion molecules depending on their cellular context and their post-translational modifications. In addition, their ability to function as blockers of adhesion may be further regulated by their subcellular localization in membrane microdomains via activation-dependent linkage with the actin cytoskeleton. To gain further insights into the function and regulation of CD34-type molecules, we sought to identify the intracellular ligands that govern their localization. Using both genetic and biochemical approaches, we have identified the Na(+)/H(+) exchanger regulatory factor-1 (NHERF-1) as a selective ligand for podocalyxin and endoglycan but not for the closely related CD34. Furthermore, we show that NHERF-1 is expressed by all c-kit(+) /lineage marker(-)/Sca-1(+) cells, which are known to express podocalyxin and have long-term repopulating abilities. Finally, we show that these proteins relocalize and colocalize in response to cytokine signaling. The results suggest that this cytosolic adaptor protein may be important for mobilization of CD34-type proteins in the plasma membrane and may thereby regulate their ability to block or enhance hematopoietic cell adhesion.
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Affiliation(s)
- Poh C Tan
- The Biomedical Research Centre, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada.
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11
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Laroche V, McKenna DH, Moroff G, Schierman T, Kadidlo D, McCullough J. Cell loss and recovery in umbilical cord blood processing: a comparison of postthaw and postwash samples. Transfusion 2005; 45:1909-16. [PMID: 16371043 DOI: 10.1111/j.1537-2995.2005.00638.x] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND Engraftment after umbilical cord blood (UCB) transplantation is highly dependent on nucleated cell (NC) and CD34+ cell content. Current standard postthaw (PT) processing includes a wash step to remove dimethyl sulfoxide (DMSO), lysed red cells, and stroma. The contribution of the wash step to cell loss and ultimately the dose of cells available for transplant have yet to be systematically reported. This study examines the effect of the wash step as well as that of PT storage on various quality control variables of UCB units. STUDY DESIGN AND METHODS Ten units were thawed and washed based on the New York Blood Center method. Samples were removed from each unit at six time points: prefreeze (PF), immediately PT, immediately postwash (PW), and 1, 2, and 5 hours PW. On each sample, total nucleated cell (TNC) count, CD34+ cell enumeration, colony-forming unit (CFU)-granulocyte-macrophage, and viability assays (fluorescence microscopy [acridine orange/propidium iodide, or AO/PI] and flow cytometry [7-aminoactinomycin]) were obtained. RESULTS TNC counts decreased PT and at subsequent time points; the PT TNC recovery was 89 percent compared to 82 percent PW (p < 0.01). TNC recovery decreased to 90 percent of PW (82% of PT) values (p < 0.01) and 83 percent of PW (76% of PT) values (p < 0.001), at 2 and 5 hours PW, respectively. CD34+ cell loss PT was not significant. Viability by AO/PI decreased PT and plateaued over time. In contrast, viability by flow cytometry remained higher and increased slightly over time. CFUs were significantly lower PT, recovering PW. CONCLUSIONS Our data indicate that the thawing and washing results in a substantial loss of cells, with TNC loss approaching 20 percent when compared with PF counts; the wash step was responsible for nearly half of the cell loss. The reduced PT viability was expected. Elapse of time PW resulted in further loss of NCs but no detectable significant changes in CD34+ cell content and viability and/or CFU.
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Affiliation(s)
- Vincent Laroche
- Department of Laboratory Medicine & Pathology, Division of Transfusion Medicine, University of Minnesota, Minneapolis, Minnesota 55455, USA.
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Forraz N, Pettengell R, McGuckin CP. Characterization of a lineage-negative stem-progenitor cell population optimized for ex vivo expansion and enriched for LTC-IC. ACTA ACUST UNITED AC 2004; 22:100-8. [PMID: 14688396 DOI: 10.1634/stemcells.22-1-100] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Current hematopoietic stem cell transplantation protocols rely heavily upon CD34+ cells to estimate hematopoietic stem and progenitor cell (HSPC) yield. We and others previously reported CD133+ cells to represent a more primitive cell population than their CD34+ counterparts. However, both CD34+ and CD133+ cells still encompass cells at various stages of maturation, possibly impairing long-term marrow engraftment. Recent studies demonstrated that cells lacking CD34 and hematopoietic lineage markers have the potential of reconstituting long-term in vivo hematopoiesis. We report here an optimized, rapid negative-isolation method that depletes umbilical cord blood (UCB) mononucleated cells (MNC) from cells expressing hematopoietic markers (CD45, glycophorin-A, CD38, CD7, CD33, CD56, CD16, CD3, and CD2) and isolates a discrete lineage-negative (Lin-) cell population (0.10% +/- 0.02% MNC, n=12). This primitive Lin- cell population encompassed CD34+/- and CD133+/- HSPC and was also enriched for surface markers involved in HSPC migration, adhesion, and homing to the bone marrow (CD164, CD162, and CXCR4). Moreover, our depletion method resulted in Lin- cells being highly enriched for long-term culture-initiating cells when compared with both CD133+ cells and MNC. Furthermore, over 8 weeks in liquid culture stimulated by a cytokine cocktail optimized for HSPC expansion, TPOFLK (thrombopoietin 10 ng/ml, Flt3 ligand 50 ng/ml, c-Kit ligand 20 ng/ml) Lin- cells underwent slow proliferation but maintained/expanded more primitive HSPC than CD133+ cells. Therefore, our Lin- stem cell offers a promising alternative to current HSPC selection methods. Additionally, this work provides an optimized and well-characterized cell population for expansion of UCB for a wider therapeutic potential, including adult stem cell transplantation.
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Affiliation(s)
- Nicolas Forraz
- King-George Laboratory, St. George's Hospital Medical School and Kingston University, London, UK
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13
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Abstract
The degree to which these elephants are disruptive to the steady advancement of the adult stem cell field will become clear with time. In some ways they enliven the discourse, but in many ways they interfere with efficient progress. Naming these elephants is a first step toward dealing with them. If we remain aware of these issues when evaluating new research, we are less likely to make careless mistakes, and we are more likely to be able to hold scientists, politicians, journalists, and entrepreneurs accountable for their practices. Although all adult stem cell researchers will spend time profitably riding some of these elephants, we will all inevitably spend more time cleaning up after them. Perhaps open, careful, and unbiased discussions of these elephants will help the cleanup work be less odious and completed sooner, rather than later.
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Affiliation(s)
- Neil D Theise
- Department of Pathology, Division of Digestive Diseases, Beth Israel Medical Center, New York, NY 10003, USA.
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14
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Schipper LF, Brand A, Reniers N, Melief CJJ, Willemze R, Fibbe WE. Differential maturation of megakaryocyte progenitor cells from cord blood and mobilized peripheral blood. Exp Hematol 2003; 31:324-30. [PMID: 12691920 DOI: 10.1016/s0301-472x(03)00004-3] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
OBJECTIVE In comparison with stem cell transplantation using bone marrow or cytokine-mobilized peripheral blood, cord blood transplantation is characterized by delayed engraftment, in particular platelet recovery. The differences in the kinetics of engraftment may be related to quantitative differences in the numbers of stem cells and megakaryocyte progenitor cells and/or to qualitative differences between megakaryocyte progenitor cells in these grafts. We compared the hematopoietic composition of these grafts and determined the distribution of mature and immature megakaryocyte progenitor cells in cord blood and mobilized peripheral blood and their in vitro kinetic behavior. METHODS Megakaryocyte progenitor cell subpopulations from cord blood (CB) and mobilized peripheral blood (PBSC) were expanded in vitro in the presence of mpl-ligand. The developmental differences during expansion of megakaryocyte progenitors were analyzed by flow cytometry and progenitor assays. RESULTS We found that the immature (CD34(+)/CD41(-)) subpopulation from CB contains more than 98% of all megakaryocyte progenitor cells, responsible for 99% of all megakaryocytic cells cultured during 2 weeks. The CB CD34(+)/CD41(+) subpopulation shows no contribution to megakaryocytic cell formation. In contrast, in PBSC the mature (CD34(+)/CD41(+)) subpopulation contains 7% of all megakaryocyte progenitor cells. Moreover, CD34(+) cells from CB and PBSC also showed distinct phenotypic differences during maturation in vitro. PBSC megakaryocyte progenitor cells transiently express both CD34 and CD41 during maturation in vitro, whereas CB progenitor cells transiently lack expression of both markers before differention into (CD34(-)/CD41(+)) megakaryocytic cells. CONCLUSION The in vitro data indicate the presence of different developmental stages of megakaryocyte progenitor cells in CB as compared to PBSC. These differences in composition and maturation between CB and PBSC may be related to the different kinetics of engraftment following transplantation of these stem cell sources.
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Dao MA, Arevalo J, Nolta JA. Reversibility of CD34 expression on human hematopoietic stem cells that retain the capacity for secondary reconstitution. Blood 2003; 101:112-8. [PMID: 12393633 DOI: 10.1182/blood-2002-01-0025] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The cell surface protein CD34 is frequently used as a marker for positive selection of human hematopoietic stem/progenitor cells in research and in transplantation. However, populations of reconstituting human and murine stem cells that lack cell surface CD34 protein have been identified. In the current studies, we demonstrate that CD34 expression is reversible on human hematopoietic stem/progenitor cells. We identified and functionally characterized a population of human CD45(+)/CD34(-) cells that was recovered from the bone marrow of immunodeficient beige/nude/xid (bnx) mice 8 to 12 months after transplantation of highly purified human bone marrow-derived CD34(+)/CD38(-) stem/progenitor cells. The human CD45(+) cells were devoid of CD34 protein and mRNA when isolated from the mice. However, significantly higher numbers of human colony-forming units and long-term culture-initiating cells per engrafted human CD45(+) cell were recovered from the marrow of bnx mice than from the marrow of human stem cell-engrafted nonobese diabetic/severe combined immunodeficient mice, where 24% of the human graft maintained CD34 expression. In addition to their capacity for extensive in vitro generative capacity, the human CD45(+)/CD34(-) cells recovered from the bnx bone marrow were determined to have secondary reconstitution capacity and to produce CD34(+) progeny following retransplantation. These studies demonstrate that the human CD34(+) population can act as a reservoir for generation of CD34(-) cells. In the current studies we demonstrate that human CD34(+)/CD38(-) cells can generate CD45(+)/CD34(-) progeny in a long-term xenograft model and that those CD45(+)/CD34(-) cells can regenerate CD34(+) progeny following secondary transplantation. Therefore, expression of CD34 can be reversible on reconstituting human hematopoietic stem cells.
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Affiliation(s)
- Mo A Dao
- Division of Research Immunology and Bone Marrow Transplantation, Children's Hospital of Los Angeles, CA, USA
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16
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Darley RL, Pearn L, Omidvar N, Sweeney M, Fisher J, Phillips S, Hoy T, Burnett AK. Protein kinase C mediates mutant N-Ras-induced developmental abnormalities in normal human erythroid cells. Blood 2002; 100:4185-92. [PMID: 12393454 DOI: 10.1182/blood-2002-05-1358] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
RAS mutations are one of the most frequent molecular abnormalities associated with myeloid leukemia and preleukemia, yet there is a poor understanding of how they contribute to the pathogenesis of these conditions. Here, we describe the consequences of ectopic mutant N-Ras (N-Ras*) expression on normal human erythropoiesis. We show that during early (erythropoietin [EPO]-independent) erythropoiesis, N-Ras* promoted the amplification of a phenotypically primitive but functionally defective subpopulation of CD34(+) erythroblasts. N-Ras* also up-regulated the expression of megakaryocyte antigens on human erythroblasts. Although early erythroblasts expressing N-Ras* were able to respond to erythropoietin and generate mature progeny, this occurred with greatly reduced efficiency, probably explaining the poor colony growth characteristics of these cells. We further report that this oncogene promoted the expression and activation of protein kinase C (PKC) and that the effects of N-Ras* on erythropoiesis could be abrogated or attenuated by inhibition of PKC. Similarly, the effects of this oncogene could be partially mimicked by treatment with PKC agonist. Together, these data suggest that expression of N-Ras* is able to subvert the normal developmental cues that regulate erythropoiesis by activating PKC. This gives rise to phenotypic and functional abnormalities commonly observed in preleukemia, suggesting a direct link between RAS mutations and the pathogenesis of preleukemia.
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Affiliation(s)
- Richard L Darley
- Leukaemia Research Fund Differentiation Group, Department of Haematology, University of Wales College of Medicine, Cardiff, United Kingdom.
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17
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Drew E, Merkens H, Chelliah S, Doyonnas R, McNagny KM. CD34 is a specific marker of mature murine mast cells. Exp Hematol 2002; 30:1211-8. [PMID: 12384153 DOI: 10.1016/s0301-472x(02)00890-1] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
OBJECTIVE CD34 is a 90- to 120-kDa cell surface sialomucin that is widely used for the enrichment of human hematopoietic stem cells (HSCs) because of its selective expression on progenitor cells and absence on mature hematopoietic cells. Recently we found that CD34 is the prototypic member of a family of three proteins with similar structure and gene organization. In light of this observation, we further examined the distribution of CD34 family members in the mouse. MATERIALS AND METHODS Hematopoietic cell lines and primary tissues were evaluated for CD34 mRNA expression by Northern blot and protein expression by cell surface immunofluorescence. To confirm specific reactivity of the CD34 antibody, cells from CD34-deficient mice were used as controls. RESULTS Although CD34 mRNA was undetectable in all murine progenitor cell lines tested, high level expression was detected for bone marrow-derived mast cells (BMMCs). Likewise, cell surface immunofluorescence confirmed that CD34 is expressed by BMMCs and by in vivo peritoneal mast cells. No protein expression was observed for CD34-deficient mast cells. In addition, our data show that mast cells highly express the stem cell antigen Sca-1 and the well-known stem cell and mast cell antigen c-kit. CONCLUSIONS Our results demonstrate that, contrary to current dogma, CD34 is expressed by one mature hematopoietic lineage: mast cells. Our data also demonstrate that antigenically, murine mast cells and their precursors closely resemble HSCs and suggest caution should be used in the phenotypic characterization of HSCs to prevent mast cell contamination of stem cell preparations.
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Affiliation(s)
- Erin Drew
- The Biomedical Research Centre, University of British Columbia, Vancouver, BC, Canada
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18
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Pierelli L, Marone M, Bonanno G, Rutella S, de Ritis D, Mancuso S, Leone G, Scambia G. Transforming growth factor-beta1 causes transcriptional activation of CD34 and preserves haematopoietic stem/progenitor cell activity. Br J Haematol 2002; 118:627-37. [PMID: 12139758 DOI: 10.1046/j.1365-2141.2002.03604.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Stem/progenitor cells endowed with in vitro and in vivo haematopoietic activity express the surface protein CD34. Transforming growth factor beta1 (TGF-beta1) is one of the soluble molecules that regulate cell cycle and differentiation of haematopoietic cells, but has pleiotropic activities depending on the state of responsiveness of the target cells. It has previously been shown that TGF-beta1 maintains human CD34+ haematopoietic progenitors in an undifferentiated state, independently of any cell cycle effect. Here, we have shown that TGF-beta1 upregulates the human CD34, an effect that was evident in primary stem/progenitor cells (CD34+lin-) both at the transcriptional and protein levels, and was not associated with any relevant effect on cell growth. The presence of TGF-beta1 influenced differentiation, maintaining primary CD34+/Lin- in an undifferentiated state. This effect was associated with Smad activation and with a dramatic decrease in p38 phosphorylation. Moreover, blocking p38 phosphorylation by the SB202190 inhibitor increased CD34 RNA levels but did not enhance CD34 protein expression in CD34+/Lin- cells, suggesting that modulation of multiple signalling pathways is necessary to reproduce TGF-beta1 effects. These data establish the role that TGF-beta1 has in the modulation of the CD34 stem/progenitor protein and stem/progenitor functions, providing important clues for understanding haematopoietic development and a potential tool for the modulation of human haematopoiesis.
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Affiliation(s)
- Luca Pierelli
- Istituto di Ematologia, Dipartimento per la Salute della Donna e della Vita Nascente, Universitá Cattolica del Sacro Cuore, Largo A. Gemelli 8, 00168 Rome, Italy.
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19
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Torlakovic G, Langholm R, Torlakovic E. CD34/QBEND10 immunostaining in the bone marrow trephine biopsy: a study of CD34-positive mononuclear cells and megakaryocytes. Arch Pathol Lab Med 2002; 126:823-8. [PMID: 12088452 DOI: 10.5858/2002-126-0823-cqiitb] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
CONTEXT The immunohistochemical detection of CD34 protein using QBEND10 antibody in bone marrow trephine biopsies was shown recently to be a precise method for quantitation of blasts and a possibly useful approach in diagnosis and classification of myelodysplastic syndrome. OBJECTIVES To evaluate CD34+ cells in bone marrow biopsies with various diagnoses and to assess how counts obtained using this method correlate with blast counts obtained by traditional morphologic evaluation of bone marrow smears. DESIGN Bone marrow trephine biopsies from 108 adult patients were evaluated by immunohistochemistry using anti-CD34 antibody (QBEND10). CD34+ mononuclear cells were counted and compared with the blast counts in the bone marrow aspirate smears or imprints. CD34+ mononuclear cell clusters and CD34+ megakaryocytes were also recorded. The type of positivity (membranous vs cytoplasmic) and the percentage of CD34+ megakaryocytes were evaluated because the presence of CD34+ megakaryocytes was recently suggested to be present in myelodysplastic syndrome, but not in myeloproliferative disease or nonneoplastic bone marrow. RESULTS Six of 24 biopsies with partial involvement by non-Hodgkin lymphoma and 5 of 60 biopsies with reactive changes had 5% to 10% CD34+ mononuclear cells and were associated with lymphocytosis and increased hematogones. The CD34+ mononuclear cell clusters were found only in myelodysplastic syndrome and myeloproliferative disease. The CD34+ megakaryocytes were present in all diagnostic groups. CONCLUSION The number of CD34+ mononuclear cells was often slightly higher than the number of myeloid blasts in the bone marrow smears, probably due to increased hematogones. The presence and the number of CD34+ megakaryocytes do not appear to have diagnostic value, but this finding should be further investigated in relation to clinical parameters.
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Affiliation(s)
- Goran Torlakovic
- Department of Pathology, The Norwegian Radium Hospital, Oslo, Norway
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20
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Marone M, Scambia G, Bonanno G, Rutella S, de Ritis D, Guidi F, Leone G, Pierelli L. Transforming growth factor-beta1 transcriptionally activates CD34 and prevents induced differentiation of TF-1 cells in the absence of any cell-cycle effects. Leukemia 2002; 16:94-105. [PMID: 11840268 DOI: 10.1038/sj.leu.2402334] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2001] [Accepted: 08/21/2001] [Indexed: 11/09/2022]
Abstract
A number of cytokines modulate self-renewal and differentiation of hematopoietic elements. Among these is transforming growth factor beta1 (TGF-beta1), which regulates cell cycle and differentiation of hematopoietic cells, but has pleiotropic activities depending on the state of responsiveness of the target cells. It has been previously shown by us and other authors that TGF-beta1 maintains human CD34(+) hematopoietic progenitors in an undifferentiated state, independently of any cell cycle effects, and that depletion of TGF-beta1 triggers differentiation accompanied by a decrease in CD34 antigen expression. In the present work, we show that exogenous TGF-beta1 upregulates the human CD34 antigen in the CD34(+) cell lines TF-1 and KG-1a, but not in the more differentiated CD34(-) cell lines HL-60 and K-562. We further studied this effect in the pluripotent erythroleukemia cell line TF-1. Here, TGF-beta1 did not effect cell growth, but induced transcriptional activation of full-length CD34 and prevented differentiation induced by differentiating agents. This effect was associated with nuclear translocation of Smad-2, activation of TAK-1, and with a dramatic decrease in p38 phosphorylation. In other systems TGF-beta1 has been shown to activate a TGF-beta-activated kinase 1 (TAK1), which in turn, activates p38. The specific inhibitor of p38 phosphorylation, SB202190, also increased CD34 RNA expression, indicating the existence of a link between p-38 inhibition by TGF-beta1 and CD34 overexpression. Our data demonstrate that TGF-beta1 transcriptionally activates CD34 and prevents differentiation of TF-1 cells by acting independently through the Smad, TAK1 and p38 pathways, and thus provide important clues for the understanding of hematopoietic development and a potential tool to modify response of hematopoietic cells to mitogens or differentiating agents.
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MESH Headings
- Antigens, CD34/biosynthesis
- Antigens, CD34/genetics
- Cell Cycle/drug effects
- Cell Differentiation/drug effects
- Culture Media, Serum-Free
- Cytokines/pharmacology
- DNA-Binding Proteins/physiology
- Enzyme Activation/drug effects
- Enzyme Inhibitors/pharmacology
- Gene Expression Regulation, Leukemic/drug effects
- Genes, bcl-2
- HL-60 Cells/drug effects
- HL-60 Cells/metabolism
- Hematopoietic Stem Cells/drug effects
- Hematopoietic Stem Cells/metabolism
- Humans
- Imidazoles/pharmacology
- K562 Cells/drug effects
- K562 Cells/metabolism
- Leukemia, Erythroblastic, Acute/genetics
- Leukemia, Erythroblastic, Acute/metabolism
- Leukemia, Erythroblastic, Acute/pathology
- MAP Kinase Kinase Kinases/physiology
- MAP Kinase Signaling System/drug effects
- Mitogen-Activated Protein Kinases/antagonists & inhibitors
- Mitogen-Activated Protein Kinases/metabolism
- Neoplasm Proteins/antagonists & inhibitors
- Neoplasm Proteins/biosynthesis
- Neoplasm Proteins/genetics
- Neoplasm Proteins/physiology
- Phosphorylation/drug effects
- Protein Kinases/metabolism
- Protein Processing, Post-Translational/drug effects
- Proto-Oncogene Proteins c-bcl-2/biosynthesis
- Pyridines/pharmacology
- RNA, Messenger/biosynthesis
- RNA, Neoplasm/biosynthesis
- Reverse Transcriptase Polymerase Chain Reaction
- Smad2 Protein
- Trans-Activators/physiology
- Transcription, Genetic/drug effects
- Transforming Growth Factor beta/pharmacology
- Transforming Growth Factor beta1
- Tumor Cells, Cultured/drug effects
- Tumor Cells, Cultured/metabolism
- p38 Mitogen-Activated Protein Kinases
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Affiliation(s)
- M Marone
- Dept of Gynecology, Catholic University, Rome Italy
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21
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Felschow DM, McVeigh ML, Hoehn GT, Civin CI, Fackler MJ. The adapter protein CrkL associates with CD34. Blood 2001; 97:3768-75. [PMID: 11389015 DOI: 10.1182/blood.v97.12.3768] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
CD34 is a cell-surface transmembrane protein expressed specifically at the stem/progenitor stage of lymphohematopoietic development that appears to regulate adhesion. To elucidate intracellular signals modified by CD34, we designed and constructed glutathione-S-transferase (GST)- fusion proteins of the intracellular domain of full-length CD34 (GST-CD34i(full)). Precipitation of cell lysates using GST-CD34i(full) identified proteins of molecular mass 39, 36, and 33 kd that constitutively associated with CD34 and a 45-kd protein that associated with CD34 after adhesion. By Western analysis, we identified the 39-kd protein as CrkL. In vivo, CrkL was coimmunoprecipitated with CD34 using CD34 antibodies, confirming the association between CrkL and CD34. CD34 peptide inhibition assays demonstrated that CrkL interacts at a membrane-proximal region of the CD34 tail. To identify the CrkL domain responsible for interaction with CD34, we generated GST-fusion constructs of adapter proteins including GST-CrkL3' (C-terminal SH3) and GST-CrkL5' (N-terminal SH2SH3). Of these fusion proteins, only GST-CrkL3' could precipitate endogenously expressed CD34, suggesting that CD34 binds the C-terminal SH3 domain of CrkL. Interestingly, there appears to be differential specificity between CrkL and CrkII for CD34, because GST-CD34i(full) did not precipitate CrkII, a highly homologous Crk family member. Furthermore, GST-CD34i(full) did not bind c-Abl, c-Cbl, C3G, or paxillin proteins that are known to associate with CrkL, suggesting that CD34 directly interacts with the CrkL protein. CD34i(full) association with Grb or Shc adapter proteins was not detected. Our investigations shed new light on signaling pathways of CD34 by demonstrating that CD34 couples to the hematopoietic adapter protein CrkL. (Blood. 2001;97:3768-3775)
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Affiliation(s)
- D M Felschow
- Johns Hopkins Oncology Center, Johns Hopkins University School of Medicine, Bunting-Blaustein Cancer Research Building, 1650 Orleans St., Baltimore, MD, USA
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22
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Bonnet D. Normal and leukemic CD34-negative human hematopoietic stem cells. REVIEWS IN CLINICAL AND EXPERIMENTAL HEMATOLOGY 2001; 5:42-61. [PMID: 11486732 DOI: 10.1046/j.1468-0734.2001.00028.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Considerable progress has been made in recent years in purifying human and murine hematopoietic stem cells. The essential marker identified is the sialomucin CD34, which is expressed on primitive cells and downregulated as they differentiate into more abundant mature cells. CD34 is not unique to stem cells, however, as it is also expressed on clonogenic progenitors and some endothelial cells. Nevertheless, all clinical and experimental protocols are targeted to CD34+ cells enriched by a variety of selection methods. Recent studies in both the murine and human systems have indicated that some stem cells capable of multilineage repopulation do not express detectable levels of cell surface CD34. These studies challenge the dogma that all human repopulating cells are found in the CD34+ subset. However, the precise relationship between CD34- and CD34+ stem cells is still not well understood. In this review, the results on the discovery of the CD34- repopulating cell are summarized and the impacts this discovery may have, both clinically and in our understanding of the organization of the human hematopoietic system, are examined.
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Affiliation(s)
- D Bonnet
- Laboratory of Molecular and Cellular Biology of Hematopoiesis, Coriell Institute for Medical Research, 401 Haddon Avenue, Camden, NJ 08103, USA.
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23
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24
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Abstract
CD34, a glycophosphoprotein present in lymphohaematopoietic stem and progenitor cells, as well as in other cell types, exists in both transmembrane and intracytoplasmic forms. Transmembrane CD34 expression, which is high in the earliest haematopoietic precursors, decreases as cells mature. However, to our knowledge, there is no information on whether a decrease in transmembrane CD34 can also predict a release of the molecule from the cell membrane into the extracellular fluid. To investigate the above possibility, we studied conditions (incubation time, cell density and proliferative status) in human myeloid cells (lines KG-1a, KG-1 and cord blood-derived cells) that may cause a decrease in surface CD34 and the generation of a soluble form of the molecule. The latter, as demonstrated by Western blot analysis, adds more complexity to the proposed structural features and functional properties of CD34 in myeloid cells.
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Affiliation(s)
- M Fernández
- Unidad de Biología Celular, INTA, Universidad de Chile, and Laboratorio de Transplante de Médula Osea, Clínica Las Condes, Santiago, Chile.
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25
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Abstract
Recent evidence suggests that expression of CD34 on the cell membrane does not always correlate with stem cell activity. In the mouse, there is a highly quiescent population of stem cells that lacks CD34 expression, but has full reconstituting capacity. The current review addresses the discovery of a similar population of dormant CD34-negative human hematopoietic stem cells. This information casts some uncertainty on the benefits of CD34+ cell isolation for stem cell transplantation, until more is known about the novel CD34-negative stem cell population. Methods designed to achieve removal of specific mature blood cell lineages might prove to be most advantageous in the future.
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Affiliation(s)
- M A Dao
- Children's Hospital Los Angeles, Dept Pediatrics, University of Southern California School of Medicine, 90027, USA
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26
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27
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A Common Signaling Pathway Via Syk and Lyn Tyrosine Kinases Generated From Capping of the Sialomucins CD34 and CD43 in Immature Hematopoietic Cells. Blood 1999. [DOI: 10.1182/blood.v93.11.3723.411k02_3723_3735] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The sialomucin CD34 is a useful marker for hematopoietic stem/progenitor cells. However, the role of CD34 remains poorly understood. Here we investigate the functions of CD34 and another sialomucin CD43 coexpressed on hematopoietic stem/progenitor cells. Stimulation of undifferentiated hematopoietic KG1a cells with anti-CD34 or anti-CD43 induced homotypic cytoadhesion, accompanied by formation of a long-lived cap of CD34 and CD43 respectively, which colocalized with F-actin. Stimulation with either antibody specifically increased tyrosine phosphorylation of the identical set of proteins of Lyn, Syk, pp60, pp69, and pp77 at the capping site. These events were similar to those observed in monocytic U937 cells ectopically expressing CD34. After stimulation of KG1a cells, coimmunoprecipitation of Lyn with pp69 and pp77 and of Syk with pp37 was detected in the membrane fraction. Blockade of antibody-induced cap formation by treatment with cytochalasin D leads to inhibition of tyrosine phosphorylation of Syk and pp77 and homotypic cytoadhesion. Moreover, normal human CD34+ bone marrow cells showed cap formation of CD34 or CD43 after stimulation. These results suggest that crosslinking of either CD34 or CD43 activates the same signaling pathway for cytoadhesion through Lyn, Syk, and the novel tyrosine-phosphorylated proteins within hematopoiesis.
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28
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A Common Signaling Pathway Via Syk and Lyn Tyrosine Kinases Generated From Capping of the Sialomucins CD34 and CD43 in Immature Hematopoietic Cells. Blood 1999. [DOI: 10.1182/blood.v93.11.3723] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
AbstractThe sialomucin CD34 is a useful marker for hematopoietic stem/progenitor cells. However, the role of CD34 remains poorly understood. Here we investigate the functions of CD34 and another sialomucin CD43 coexpressed on hematopoietic stem/progenitor cells. Stimulation of undifferentiated hematopoietic KG1a cells with anti-CD34 or anti-CD43 induced homotypic cytoadhesion, accompanied by formation of a long-lived cap of CD34 and CD43 respectively, which colocalized with F-actin. Stimulation with either antibody specifically increased tyrosine phosphorylation of the identical set of proteins of Lyn, Syk, pp60, pp69, and pp77 at the capping site. These events were similar to those observed in monocytic U937 cells ectopically expressing CD34. After stimulation of KG1a cells, coimmunoprecipitation of Lyn with pp69 and pp77 and of Syk with pp37 was detected in the membrane fraction. Blockade of antibody-induced cap formation by treatment with cytochalasin D leads to inhibition of tyrosine phosphorylation of Syk and pp77 and homotypic cytoadhesion. Moreover, normal human CD34+ bone marrow cells showed cap formation of CD34 or CD43 after stimulation. These results suggest that crosslinking of either CD34 or CD43 activates the same signaling pathway for cytoadhesion through Lyn, Syk, and the novel tyrosine-phosphorylated proteins within hematopoiesis.
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29
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Häfer R, Voigt A, Gruhn B, Zintl F. Neuroblastoma cells can express the hematopoietic progenitor cell antigen CD34 as detected at surface protein and mRNA level. J Neuroimmunol 1999; 96:201-6. [PMID: 10337918 DOI: 10.1016/s0165-5728(99)00030-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Recently, we have shown the expression of the hematopoietic precursor cell antigen CD34 on neuroblastoma cells. Here, we present the CD34 expression on 16 permanent neuroblastoma cell lines and primary cell lines at the mRNA level and the flow cytometric results on neuroblastoma cells grown in the same culture and split for flow cytometric analysis and total mRNA extraction. The flow cytometry was performed using a panel of anti-CD34 antibodies covering the epitope classes I to III. In eight neuroblastoma cell lines, CD34 mRNA expression could be detected and corresponded always with the protein surface expression. Alternatively, when CD34 mRNA expression was not seen, CD34 antigen expression ranged from negative to as high as 78%. Based on these results caution should be taken with transplants obtained by CD34+ stem cell selection from neuroblastoma patients.
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Affiliation(s)
- R Häfer
- Department of Pediatrics, University of Jena, Germany.
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30
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Two New Pseudopod Morphologies Displayed by the Human Hematopoietic KG1a Progenitor Cell Line and by Primary Human CD34+Cells. Blood 1998. [DOI: 10.1182/blood.v92.10.3616] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
AbstractA primitive human hematopoietic myeloid progenitor cell line, KG1a, characterized by high expression of the CD34 surface antigen has been observed to extend long, thin pseudopodia. Once extended, these pseudopods may take on one of two newly described morphologies, tenupodia or magnupodia. Tenupodia are very thin and form in linear segments. They adhere to the substrate, can bifurcate multiple times, and often appear to connect the membranes of cells more than 300 μm apart. Magnupodia are much thicker and have been observed to extend more than 330 μm away from the cell. Magnupods are flexible and can exhibit rapid dynamic motion, extending or retracting in a few seconds. During retraction, the extended material often pools into a bulb located on the pod. Both morphologies can adhere to substrates coated with fibronectin, collagen IV, and laminin as well as plastic. The CD34 and CD44 antigens are also present on the surface of these podia. Primary human CD34+ cells from fetal liver, umbilical cord blood, adult bone marrow, and mobilized peripheral blood extend these podia as well. The morphology that these pseudopods exhibit suggest that they may play both sensory and mechanical roles during cell migration and homing after bone marrow transplantation.
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31
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Two New Pseudopod Morphologies Displayed by the Human Hematopoietic KG1a Progenitor Cell Line and by Primary Human CD34+Cells. Blood 1998. [DOI: 10.1182/blood.v92.10.3616.422k19_3616_3623] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A primitive human hematopoietic myeloid progenitor cell line, KG1a, characterized by high expression of the CD34 surface antigen has been observed to extend long, thin pseudopodia. Once extended, these pseudopods may take on one of two newly described morphologies, tenupodia or magnupodia. Tenupodia are very thin and form in linear segments. They adhere to the substrate, can bifurcate multiple times, and often appear to connect the membranes of cells more than 300 μm apart. Magnupodia are much thicker and have been observed to extend more than 330 μm away from the cell. Magnupods are flexible and can exhibit rapid dynamic motion, extending or retracting in a few seconds. During retraction, the extended material often pools into a bulb located on the pod. Both morphologies can adhere to substrates coated with fibronectin, collagen IV, and laminin as well as plastic. The CD34 and CD44 antigens are also present on the surface of these podia. Primary human CD34+ cells from fetal liver, umbilical cord blood, adult bone marrow, and mobilized peripheral blood extend these podia as well. The morphology that these pseudopods exhibit suggest that they may play both sensory and mechanical roles during cell migration and homing after bone marrow transplantation.
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32
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Beham A, Regauer S, Beham-Schmid C, Kainz J, Stammberger H. Expression of CD34-antigen in nasopharyngeal angiofibromas. Int J Pediatr Otorhinolaryngol 1998; 44:245-50. [PMID: 9780070 DOI: 10.1016/s0165-5876(98)00072-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
Formalin-fixed, paraffin-embedded and frozen tissues of 24 patients with primary nasopharyngeal angiofibroma, of whom seven had recurrences, were studied immunohistochemically for the expression of CD34 antigen using two different antibodies (HPCA-1 and QBEND 10). In all cases, there was an exclusive staining of endothelial cells, while pericytes, smooth muscle cells and stromal fibroblasts were not reactive. The staining intensity, however, was more pronounced in small tumor vessels of capillary- and sinusoidal-type than in larger vessels, which were usually characterized by an irregular smooth muscle coat. This differential staining indicates an increased proliferative potential of the endothelium of the small vessel component of nasopharyngeal angiofibroma (neoangiogenesis) and an inhibitory influence of vascular smooth muscle cells on endothelial cell growth. Moreover, the positive immunoreaction of all endothelial cells for CD34 is indicative of the absence of lymphatic vessels, which confirms previous ultrastructural observations. No differences in the staining pattern were observed between primary versus recurrent tumors, formalin fixed, paraffin embedded versus snap-frozen acetone fixed material, or between both CD34 antibodies. Our findings indicate that nasopharyngeal angiofibroma is a vasoproliferative malformation.
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Affiliation(s)
- A Beham
- Institute of Pathology, University of Graz Medical School, Austria
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The Cytoplasmic Domain of Stem Cell Antigen CD34 Is Essential for Cytoadhesion Signaling But Not Sufficient for Proliferation Signaling. Blood 1998. [DOI: 10.1182/blood.v91.4.1152] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
AbstractCD34 is widely used as a marker in the identification and purification of human hematopoietic stem and progenitor cells; however, its function within hematopoiesis is largely unknown. We have investigated the contribution of cytoplasmic domain of CD34 in cytoadhesion signaling and proliferation signaling in hematopoietic cells. Engagement of particular determinants of CD34 by monoclonal antibodies leads to homotypic adhesiveness of the full-length CD34-transfected BaF3 cells. However, this homotypic adhesiveness is abrogated in BaF3 cells transfected with the truncated CD34 lacking the cytoplasmic domain. Cytoadhesion signaling through the cytoplasmic domain of CD34 cannot be restored through that of erythropoietin receptor (EPOR) or granulocyte colony-stimulating factor receptor (G-CSFR), suggesting that the cytoplasmic domain of CD34 is required for its signal transduction of cellular adhesion. In constrast, we show that replacing the cytoplasmic domain of EPOR or G-CSFR with that of CD34 abolished growth signal transduction in response to EPO or G-CSF in the chimeric receptor-transfected BaF3, 32D, and FDCP1 cells, whereas the wild-type EPOR- or G-CSFR-transfected cells responded to EPO or G-CSF growth signaling well. These results suggest that the cytoplasmic portion of CD34 may not contain the elements necessary to transduce a proliferative signal in hematopoietic cells. Thus, the function of CD34 in hematopoiesis is primarily on hematopoietic cell adhesion.
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Abstract
Granulocyte colony stimulating factor (G-CSF) regulates survival, proliferation, differentiation, and activation of myeloid cells. It binds to a high affinity receptor (G-CSF-R) expressed on myeloid cells, for which the signal transduction mechanisms other than protein tyrosine kinase (PTK) activation have not been completely identified. We explored the potential involvement of protein kinase-C (PKC) in G-CSF-R signal transduction. In this report, we provide direct evidence of PKC activation by G-CSF-R. G-CSF treatment of peripheral blood neutrophils, granulocytic cell lines (HL-60, NFS-60, KG-1), and monocytic cell lines (WEHI-3B,U-937) resulted in PKC activation. Chelerythrine chloride and HA-100, an isoquinolinesulfonamide derivative, the specific inhibitors of PKC, 1,2-Bis(2-aminophenoxy)ethane-N,N,N',N'-tetra-acetic acid (BAPTA), a chelator of intracellular calcium, and 3,4,5-trimethoxybenzoic acid 8-(diethylamino)-octyl ester (TMB-8), an inhibitor of intracellular calcium release, blocked G-CSF-induced PKC activation in HL-60 cells, and reduced CD11b upregulation in neutrophils, but did not affect ligand-binding or down-modulation of G-CSF-R. Methyl 2,5-dihydroxycinnamate (MDHC), a potent inhibitor of protein tyrosine kinases (PTK), also inhibited PKC activation in response to G-CSF treatment, suggesting that PKC activation may occur downstream of PTK activation. Our results demonstrate the involvement of PKC in G-CSF-R signal transduction, and suggest a common signaling pathway in myeloid cells of granulocytic and monocytic lineages.
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Affiliation(s)
- R V Deshpande
- James Ewing Laboratory of Developmental Hematopoiesis, Memorial Sloan-Kettering Cancer Center, New York, New York 10021, USA
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35
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Abstract
CD34 monoclonal antibodies bind selectively to the most immature 1.5% of low-density human bone marrow mononuclear cells, including terminal deoxynucleotidyl transferase-positive lymphoid precursor cells, all types of in vitro assayed hematopoietic progenitor cells, and lymphohematopoietic stem cells capable of reconstituting myeloablated humans in clinical transplantation. Positive selection of highly enriched CD34+ stem and progenitor cells is widely used in research and is now being investigated in many applications of autologous and allogeneic clinical transplantation. More highly purified stem cells are also desired in research and may have clinical use. Immunoaffinity isolation of CD34+ cell subsets using antibodies against CD38 permits 10-100-fold further purification of stem cells. It will be valuable to be able to expand stem and progenitor cells from small marrow and blood samples. We are now identifying the genes expressed in stem and progenitor cells to eventually allow the control of stem and progenitor cell survival, proliferation, and differentiation.
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Affiliation(s)
- C I Civin
- Oncology Center, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287-5001, USA
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Hoke D, Mebius RE, Dybdal N, Dowbenko D, Gribling P, Kyle C, Baumhueter S, Watson SR. Selective modulation of the expression of L-selectin ligands by an immune response. Curr Biol 1995; 5:670-8. [PMID: 7552178 DOI: 10.1016/s0960-9822(95)00132-1] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
BACKGROUND The adhesion molecule L-selectin is expressed on the cell surface of lymphocytes and mediates their migration from the bloodstream into lymph nodes. L-selectin is able to recognize four glycoprotein ligands, three of which--Sgp50, Sgp90, and Sgp200--are sulphated, bind specifically to L-selectin and are synthesized by the high endothelial venules of the peripheral and mesenteric lymph nodes. One of these three sulphated L-selectin ligands, Sgp90, has been shown to be identical to the known surface marker CD34 and is expressed on the cell surface of endothelial cells. The cDNA encoding Sgp50 has been cloned, and its product, which has been designated GlyCAM-1, is secreted. The third ligand, Sgp200, is both secreted and cell-associated. We have investigated how the expression of these sulphated glycoproteins is regulated during an immune response. RESULTS Here we demonstrated that, during a primary immune response, the expression and secretion of both GlyCAM-1 and Sgp200 are reduced, recovering to normal levels 7-10 days after antigen stimulation. In contrast, the expression of cell-associated CD34 and Sgp200 is relatively unaffected. These results may account for the modest decreases in the binding of an L-selectin-IgG fusion protein to high endothelial venules of inflamed peripheral lymph nodes that have been observed after antigen exposure. In vivo experiments show that, following the decrease in the levels of secreted GlyCAM-1 and Sgp200, migration of lymphocytes from the blood stream into lymph nodes remains L-selectin-dependent, but more lymphocytes home to antigen-primed than unprimed peripheral lymph nodes. CONCLUSIONS We suggest that the secreted forms of the L-selectin ligands GlyCAM-1 and Sgp200 act as modulators of cell adhesion, and that cell-associated CD34 and Sgp200 are the ligands that mediate the initial loose binding of lymphocytes to high endothelial venules.
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Affiliation(s)
- D Hoke
- Department of Immunology, Genentech, South San Francisco, California 94080, USA
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Knapp W, Strobl H, Scheinecker C, Bello-Fernandez C, Majdic O. Molecular characterization of CD34+ human hematopoietic progenitor cells. Ann Hematol 1995; 70:281-96. [PMID: 7543291 DOI: 10.1007/bf01696614] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- W Knapp
- Institute of Immunology, University of Vienna, Austria
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Abstract
The myelodysplastic syndromes (MDS) are a heterogeneous group of disorders of hematopoiesis entailing hyperproliferative and ineffective hematopoiesis resulting in refractory cytopenia(s), and increased risk of transformation into acute myeloblastic leukemia (AML). The widely used classification defined by the French-American-British group (FAB) recognizes 5 cytological subtypes of different prognosis, based essentially on the presence and the frequency of marrow blasts. The percentage of marrow blasts does not exceed 30%, hence, direct investigations of biological and biochemical events of MDS blast cells have been hampered. The CD34 antigen is currently unique in its narrow specificity of expression on human lymphohematopoietic progenitor cells. This cell membrane phosphoglycoprotein has been used for immunologic blast cell purification, notwithstanding the frequency of marrow blasts, and has provided a set of tools for investigations of MDS i.e. a direct comparison of the nature of blast cells in each of the MDS subtypes, using immunologic, biologic, biochemical and molecular biological methodology. A combination of serum-free medium and a purification method for blast cells provided evidence that the progenitor cell growth abnormalities in these disorders involve a defect in the capacity of progenitor cells to respond to stimulation with growth factor(s), and has presented direct evidence for the manner in which myelodysplastic CD34+ cells are impaired.
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Affiliation(s)
- K Sawada
- Department of Internal Medicine II, Hokkaido University School of Medicine, Japan
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Sutherland DR, Stewart AK, Keating A. CD34 antigen: molecular features and potential clinical applications. Stem Cells 1993; 11 Suppl 3:50-7. [PMID: 7507757 DOI: 10.1002/stem.5530110914] [Citation(s) in RCA: 56] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Despite the wide variety of functions exhibited by mature peripheral blood cells, all are derived from a small pool (1-3%) of primitive precursor cells in the bone marrow (BM) that bear a unique surface glycoprotein, CD34. Isolated CD34+ cells are capable of reconstituting all hematopoietic lineages, both in experimental animals and in humans following intensive therapy. CD34+ cells capable of reconstituting hematopoiesis are also found at low frequency in peripheral blood (PB), a frequency which can be dramatically increased by combinations of chemotherapy and recombinant cytokines. In some cases, PB "stem cells" (PBSC) can be used to augment or even replace conventional BM autografts. The availability of CD34 antibodies has greatly aided the development of techniques for the enrichment of primitive progenitor cells, thus allowing studies of the hematopoietic potential of stem cells in vitro. Additionally, the use of CD34 antibodies for the "positive selection" of hematopoietic stem/progenitor cells from tumor-contaminated marrow may possibly represent an alternative "purging" strategy prior to transplantation. The availability of pure populations of the most primitive hematopoietic progenitor cells will also facilitate study of genetic manipulation as a practical therapeutic modality.
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