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Fasano CA, Chambers SM, Lee G, Tomishima MJ, Studer L. Retraction Notice to: Efficient Derivation of Functional Floor Plate Tissue from Human Embryonic Stem Cells. Cell Stem Cell 2023; 30:905. [PMID: 37267920 DOI: 10.1016/j.stem.2023.05.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
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Yamazaki T, Liu L, Lazarev D, Al-Zain A, Fomin V, Yeung PL, Chambers SM, Lu CW, Studer L, Manley JL. Corrigendum: TCF3 alternative splicing controlled by hnRNP H/F regulates E-cadherin expression and hESC pluripotency. Genes Dev 2019; 33:733-736. [DOI: 10.1101/gad.326983.119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Cornacchia D, Zhang C, Zimmer B, Chung SY, Fan Y, Soliman MA, Tchieu J, Chambers SM, Shah H, Paull D, Konrad C, Vincendeau M, Noggle SA, Manfredi G, Finley LWS, Cross JR, Betel D, Studer L. Lipid Deprivation Induces a Stable, Naive-to-Primed Intermediate State of Pluripotency in Human PSCs. Cell Stem Cell 2019; 25:120-136.e10. [PMID: 31155483 DOI: 10.1016/j.stem.2019.05.001] [Citation(s) in RCA: 68] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Revised: 11/21/2018] [Accepted: 04/30/2019] [Indexed: 12/22/2022]
Abstract
Current challenges in capturing naive human pluripotent stem cells (hPSCs) suggest that the factors regulating human naive versus primed pluripotency remain incompletely defined. Here we demonstrate that the widely used Essential 8 minimal medium (E8) captures hPSCs at a naive-to-primed intermediate state of pluripotency expressing several naive-like developmental, bioenergetic, and epigenomic features despite providing primed-state-sustaining growth factor conditions. Transcriptionally, E8 hPSCs are marked by activated lipid biosynthesis and suppressed MAPK/TGF-β gene expression, resulting in endogenous ERK inhibition. These features are dependent on lipid-free culture conditions and are lost upon lipid exposure, whereas short-term pharmacological ERK inhibition restores naive-to-primed intermediate traits even in the presence of lipids. Finally, we identify de novo lipogenesis as a common transcriptional signature of E8 hPSCs and the pre-implantation human epiblast in vivo. These findings implicate exogenous lipid availability in regulating human pluripotency and define E8 hPSCs as a stable, naive-to-primed intermediate (NPI) pluripotent state.
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Affiliation(s)
- Daniela Cornacchia
- Developmental Biology, The Center for Stem Cell Biology, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Chao Zhang
- Institute for Computational Biomedicine, Weill Cornell Medicine, New York, NY 10021, USA; Division of Hematology/Oncology, Department of Medicine, Weill Cornell Medicine, New York, NY 10021, USA
| | - Bastian Zimmer
- Developmental Biology, The Center for Stem Cell Biology, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Sun Young Chung
- Developmental Biology, The Center for Stem Cell Biology, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Yujie Fan
- Developmental Biology, The Center for Stem Cell Biology, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA; Weill Graduate School of Medical Sciences of Cornell University, New York, NY 10065, USA
| | - Mohamed A Soliman
- Developmental Biology, The Center for Stem Cell Biology, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA; Weill Cornell Medicine, New York, NY 10065, USA
| | - Jason Tchieu
- Developmental Biology, The Center for Stem Cell Biology, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Stuart M Chambers
- Developmental Biology, The Center for Stem Cell Biology, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Hardik Shah
- Donald B. and Catherine C. Marron Cancer Metabolism Center, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Daniel Paull
- The New York Stem Cell Foundation Research Institute, New York, NY 10019, USA
| | - Csaba Konrad
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10065, USA
| | - Michelle Vincendeau
- Developmental Biology, The Center for Stem Cell Biology, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Scott A Noggle
- The New York Stem Cell Foundation Research Institute, New York, NY 10019, USA
| | - Giovanni Manfredi
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10065, USA
| | - Lydia W S Finley
- Center for Epigenetics Research, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA; Cell Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Justin R Cross
- Donald B. and Catherine C. Marron Cancer Metabolism Center, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Doron Betel
- Institute for Computational Biomedicine, Weill Cornell Medicine, New York, NY 10021, USA; Division of Hematology/Oncology, Department of Medicine, Weill Cornell Medicine, New York, NY 10021, USA
| | - Lorenz Studer
- Developmental Biology, The Center for Stem Cell Biology, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA.
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Yamazaki T, Liu L, Lazarev D, Al-Zain A, Fomin V, Yeung PL, Chambers SM, Lu CW, Studer L, Manley JL. TCF3 alternative splicing controlled by hnRNP H/F regulates E-cadherin expression and hESC pluripotency. Genes Dev 2018; 32:1161-1174. [PMID: 30115631 PMCID: PMC6120717 DOI: 10.1101/gad.316984.118] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2018] [Accepted: 06/22/2018] [Indexed: 12/13/2022]
Abstract
Yamazaki et al. show that alternative splicing creates two TCF3 isoforms (E12 and E47) and identified two related splicing factors, hnRNPs H1 and F (hnRNP H/F), that regulate TCF3 splicing. Expression of known TCF3 target E-cadherin, critical for maintaining ESC pluripotency, is repressed by E47 but not by E12. Alternative splicing (AS) plays important roles in embryonic stem cell (ESC) differentiation. In this study, we first identified transcripts that display specific AS patterns in pluripotent human ESCs (hESCs) relative to differentiated cells. One of these encodes T-cell factor 3 (TCF3), a transcription factor that plays important roles in ESC differentiation. AS creates two TCF3 isoforms, E12 and E47, and we identified two related splicing factors, heterogeneous nuclear ribonucleoproteins (hnRNPs) H1 and F (hnRNP H/F), that regulate TCF3 splicing. We found that hnRNP H/F levels are high in hESCs, leading to high E12 expression, but decrease during differentiation, switching splicing to produce elevated E47 levels. Importantly, hnRNP H/F knockdown not only recapitulated the switch in TCF3 AS but also destabilized hESC colonies and induced differentiation. Providing an explanation for this, we show that expression of known TCF3 target E-cadherin, critical for maintaining ESC pluripotency, is repressed by E47 but not by E12.
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Affiliation(s)
- Takashi Yamazaki
- Department of Biological Sciences, Columbia University, New York, New York 10027, USA
| | - Lizhi Liu
- Department of Biological Sciences, Columbia University, New York, New York 10027, USA
| | - Denis Lazarev
- Department of Biological Sciences, Columbia University, New York, New York 10027, USA
| | - Amr Al-Zain
- Department of Biological Sciences, Columbia University, New York, New York 10027, USA
| | - Vitalay Fomin
- Department of Biological Sciences, Columbia University, New York, New York 10027, USA
| | - Percy Luk Yeung
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Child Health Institute of New Jersey, New Brunswick, New Jersey 08901, USA
| | - Stuart M Chambers
- The Center for Stem Cell Biology, Sloan Kettering Institute, New York, New York 10065, USA.,Developmental Biology Program, Sloan Kettering Institute, New York, New York 10065, USA
| | - Chi-Wei Lu
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Child Health Institute of New Jersey, New Brunswick, New Jersey 08901, USA
| | - Lorenz Studer
- The Center for Stem Cell Biology, Sloan Kettering Institute, New York, New York 10065, USA.,Developmental Biology Program, Sloan Kettering Institute, New York, New York 10065, USA
| | - James L Manley
- Department of Biological Sciences, Columbia University, New York, New York 10027, USA
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Chambers SM, Mica Y, Lee G, Studer L, Tomishima MJ. Dual-SMAD Inhibition/WNT Activation-Based Methods to Induce Neural Crest and Derivatives from Human Pluripotent Stem Cells. Methods Mol Biol 2016; 1307:329-343. [PMID: 24301074 DOI: 10.1007/7651_2013_59] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The neural crest (NC) is a transient population of multipotent cells giving rise to the peripheral nervous system, skin pigmentation, heart, and facial mesenchyme. The broad cell fate potential of NC makes it an attractive cell fate to derive from human pluripotent stem cells (hPSCs) for exploring embryonic development, modeling disease, and generating cells for transplantation. Here, we discuss recent publications and methods for efficiently differentiating hPSCs into NC. We also provide methods to direct NC into two different terminal fates: melanocytes and sensory neurons.
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Affiliation(s)
- Stuart M Chambers
- Developmental Biology Program, Center for Stem Cell Biology, Sloan-Kettering Institute, 1275 York Ave, New York, NY, 10065, USA
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Abstract
A major barrier in understanding nervous system development is modeling the cellular interactions that form the human brain. Recently, in the journal Nature, Lancaster et al. (2013) established a protocol for culturing pluripotent stem cell (PSC)-derived "cerebral organoids" that mimics the developing human brain's cellular organization, segregates into distinct brain regions, and models microcephaly.
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Affiliation(s)
- Stuart M Chambers
- Center for Stem Cell Biology, Sloan-Kettering Institute, 1275 York Avenue, New York, NY 10065, USA; Developmental Biology Program, Sloan-Kettering Institute, 1275 York Avenue, New York, NY 10065, USA
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Mica Y, Lee G, Chambers SM, Tomishima MJ, Studer L. Modeling neural crest induction, melanocyte specification, and disease-related pigmentation defects in hESCs and patient-specific iPSCs. Cell Rep 2013; 3:1140-52. [PMID: 23583175 DOI: 10.1016/j.celrep.2013.03.025] [Citation(s) in RCA: 185] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2012] [Revised: 01/26/2013] [Accepted: 03/18/2013] [Indexed: 12/18/2022] Open
Abstract
Melanocytes are pigment-producing cells of neural crest (NC) origin that are responsible for protecting the skin against UV irradiation. Pluripotent stem cell (PSC) technology offers a promising approach for studying human melanocyte development and disease. Here, we report that timed exposure to activators of WNT, BMP, and EDN3 signaling triggers the sequential induction of NC and melanocyte precursor fates under dual-SMAD-inhibition conditions. Using a SOX10::GFP human embryonic stem cell (hESC) reporter line, we demonstrate that the temporal onset of WNT activation is particularly critical for human NC induction. Subsequent maturation of hESC-derived melanocytes yields pure populations that match the molecular and functional properties of adult melanocytes. Melanocytes from Hermansky-Pudlak syndrome and Chediak-Higashi syndrome patient-specific induced PSCs (iPSCs) faithfully reproduce the ultrastructural features of disease-associated pigmentation defects. Our data define a highly specific requirement for WNT signaling during NC induction and enable the generation of pure populations of human iPSC-derived melanocytes for faithful modeling of pigmentation disorders.
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Affiliation(s)
- Yvonne Mica
- The Center for Stem Cell Biology, Sloan-Kettering Institute for Cancer Research, 1275 York Avenue, New York, NY 10065, USA
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Harel S, Tu EY, Weisberg S, Esquilin M, Chambers SM, Liu B, Carson CT, Studer L, Reizis B, Tomishima MJ. ZFX controls the self-renewal of human embryonic stem cells. PLoS One 2012; 7:e42302. [PMID: 22879936 PMCID: PMC3411758 DOI: 10.1371/journal.pone.0042302] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2011] [Accepted: 07/06/2012] [Indexed: 11/18/2022] Open
Abstract
Embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) offer great promise in regenerative medicine and disease modeling due to their unlimited self-renewal and broad differentiation capacity. There is evidence that the growth properties and critical signaling pathways differ between murine and human ESCs; therefore, it is essential to perform functional studies to test the putatively conserved mechanisms of pluripotent stem cell self-renewal between species. Previously, we identified the transcription factor Zfx as a key regulator of self-renewal in murine ESCs. Here we extend those findings to human ESCs. ZFX knockdown in hESCs hindered clonal growth and decreased colony size after serial replating. ZFX overexpression enhanced clone formation in the presence of Y-27632, increased colony size at low density and decreased expression of differentiation-related genes in human ESCs. ZFX-overexpressing hESCs resisted spontaneous differentiation but could be directed to differentiate into endodermal and neural cell fates when provided with the appropriate cues. Thus, ZFX acts as a molecular rheostat regulating the balance between self-renewal and differentiation in hESCs, revealing the close evolutionary conservation of the self-renewal mechanisms in murine and human ESCs.
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Affiliation(s)
- Sivan Harel
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, New York, United States of America
| | - Edmund Y. Tu
- Developmental Biology Program, Sloan-Kettering Institute, New York, New York, United States of America
| | - Stuart Weisberg
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, New York, United States of America
| | - Manuel Esquilin
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, New York, United States of America
| | - Stuart M. Chambers
- Developmental Biology Program, Sloan-Kettering Institute, New York, New York, United States of America
| | - Becky Liu
- Developmental Biology Program, Sloan-Kettering Institute, New York, New York, United States of America
| | | | - Lorenz Studer
- Developmental Biology Program, Sloan-Kettering Institute, New York, New York, United States of America
| | - Boris Reizis
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, New York, United States of America
- * E-mail: (BR); (MJT)
| | - Mark J. Tomishima
- Developmental Biology Program, Sloan-Kettering Institute, New York, New York, United States of America
- * E-mail: (BR); (MJT)
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Chambers SM, Qi Y, Mica Y, Lee G, Zhang XJ, Niu L, Bilsland J, Cao L, Stevens E, Whiting P, Shi SH, Studer L. Combined small-molecule inhibition accelerates developmental timing and converts human pluripotent stem cells into nociceptors. Nat Biotechnol 2012; 30:715-20. [PMID: 22750882 PMCID: PMC3516136 DOI: 10.1038/nbt.2249] [Citation(s) in RCA: 412] [Impact Index Per Article: 34.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2012] [Accepted: 04/30/2012] [Indexed: 12/23/2022]
Abstract
There has been considerable progress in identifying signaling pathways directing the differentiation of human pluripotent stem cells (hPSCs) into specialized cell types including neurons. However, extrinsic factor-based differentiation of hPSCs is a slow, step-wise process mimicking the protracted timing of normal human development. Using a small molecule screen we identified a combination of five small molecule pathway inhibitors sufficient to yield hPSC-derived neurons at >75% efficiency within 10 days of differentiation. The resulting neurons express canonical markers and functional properties of human nociceptors including TTX-resistant, SCN10A-dependent sodium currents and response to nociceptive stimuli including ATP and capsaicin. Neuronal fate acquisition occurs three-fold faster than during in vivo1 development suggesting that use of small molecule pathway inhibitors could develop into a general strategy for accelerating developmental timing in vitro. The quick and high efficiency derivation of nociceptors offers unprecedented access to this medically relevant cell type for studies of human pain.
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Affiliation(s)
- Stuart M Chambers
- Center for Stem Cell Biology, Sloan-Kettering Institute, New York, New York, USA.
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Balmer NV, Weng MK, Zimmer B, Ivanova VN, Chambers SM, Nikolaeva E, Jagtap S, Sachinidis A, Hescheler J, Waldmann T, Leist M. Epigenetic changes and disturbed neural development in a human embryonic stem cell-based model relating to the fetal valproate syndrome. Hum Mol Genet 2012; 21:4104-14. [DOI: 10.1093/hmg/dds239] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
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Abstract
Building on the discovery that MyoD expression reprograms fibroblasts into muscle, three papers (Vierbuchen et al., 2010; Ieda et al., 2010; Szabo et al., 2010) recently reported the reprogramming of fibroblasts into neurons, cardiomyocytes, and blood cell progenitors without first passing the cells through a pluripotent state. Here we discuss the advantages and challenges of harnessing this direct reprogramming method for regenerative medicine.
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Affiliation(s)
- Stuart M Chambers
- Center for Stem Cell Biology, Sloan-Kettering Institute, 1275 York Avenue, New York, NY 10065, USA.
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King KY, Baldridge MT, Weksberg DC, Chambers SM, Lukov GL, Wu S, Boles NC, Jung SY, Qin J, Liu D, Songyang Z, Eissa NT, Taylor GA, Goodell MA. Irgm1 protects hematopoietic stem cells by negative regulation of IFN signaling. Blood 2011; 118:1525-33. [PMID: 21633090 PMCID: PMC3156044 DOI: 10.1182/blood-2011-01-328682] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2011] [Accepted: 04/21/2011] [Indexed: 12/23/2022] Open
Abstract
The IFN-inducible immunity-related p47 GTPase Irgm1 has been linked to Crohn disease as well as susceptibility to tuberculosis. Previously we demonstrated that HSC quiescence and function are aberrant in mice lacking Irgm1. To investigate the molecular basis for these defects, we conducted microarray expression profiling of Irgm1-deficient HSCs. Cell-cycle and IFN-response genes are up-regulated in Irgm1(-/-) HSCs, consistent with dysregulated IFN signaling. To test the hypothesis that Irgm1 normally down-regulates IFN signaling in HSCs, we generated Irgm1(-/-)Ifngr1(-/-) and Irgm1(-/-)Stat1(-/-) double-knockout animals. Strikingly, hyperproliferation, self-renewal, and autophagy defects in Irgm1(-/-) HSCs were normalized in double-knockout animals. These defects were also abolished in Irgm1(-/-)Irgm3(-/-) double-knockout animals, indicating that Irgm1 may regulate Irgm3 activity. Furthermore, the number of HSCs was reduced in aged Irgm1(-/-) animals, suggesting that negative feedback inhibition of IFN signaling by Irgm1 is necessary to prevent hyperproliferation and depletion of the stem cell compartment. Collectively, our results indicate that Irgm1 is a powerful negative regulator of IFN-dependent stimulation in HSCs, with an essential role in preserving HSC number and function. The deleterious effects of excessive IFN signaling may explain how hematologic abnormalities arise in patients with inflammatory conditions.
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Affiliation(s)
- Katherine Y King
- Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA
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Chambers SM, Mica Y, Studer L, Tomishima MJ. Converting human pluripotent stem cells to neural tissue and neurons to model neurodegeneration. Methods Mol Biol 2011; 793:87-97. [PMID: 21913095 DOI: 10.1007/978-1-61779-328-8_6] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Human embryonic stem cells (hESCs) and the related induced pluripotent stem cells (hiPSCs) have attracted considerable attention since they can provide an unlimited source of many different tissue types. One challenge of using pluripotent cells is directing their broad differentiation potential into one specific tissue or cell fate. The cell fate choices of extraembryonic, endoderm, mesoderm, and ectoderm (including neural) lineages represent the earliest decisions. We found that pluripotent cells efficiently neuralize by blocking the signaling pathways required for alternative cell fate decisions. In this chapter, we detail methods to direct hESCs or hiPSCs into early neural cells and subsequently postmitotic neurons.
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Affiliation(s)
- Stuart M Chambers
- Developmental Biology Program, Sloan-Kettering Institute, New York, NY, USA
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Fasano CA, Chambers SM, Lee G, Tomishima MJ, Studer L. Efficient derivation of functional floor plate tissue from human embryonic stem cells. Cell Stem Cell 2010; 6:336-347. [PMID: 20362538 PMCID: PMC4336800 DOI: 10.1016/j.stem.2010.03.001] [Citation(s) in RCA: 177] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2009] [Revised: 10/02/2009] [Accepted: 03/03/2010] [Indexed: 12/24/2022]
Abstract
The floor plate (FP) is a critical signaling center during neural development located along the ventral midline of the embryo. Little is known about human FP development because of the lack of tissue accessibility. Here we report the efficient derivation of human embryonic stem cell (hESC)-derived FP tissue capable of secreting Netrin-1 and SHH and patterning primary and hESC derived tissues. FP induction in hESCs is dependent on early SHH exposure and occurs at the expense of anterior neurectoderm (AN). Global gene expression and functional studies identify SHH-mediated inhibition of Dkk-1 as key factor in FP versus AN specification. hESC-derived FP tissue is shown to be of anterior SIX6+ character but is responsive to caudalizing factors suppressing SIX6 expression and inducing a shift in usage of region-specific SHH enhancers. These data define the early signals that drive human FP versus AN specification and determine regional identity in hESC-derived FP.
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Affiliation(s)
- Christopher A Fasano
- Developmental Biology Program, Sloan-Kettering Institute, 1275 York Ave, New York, NY 10065, USA; New York Neural Stem Cell Institute, Rensselaer, NY 12144, USA.
| | - Stuart M Chambers
- Developmental Biology Program, Sloan-Kettering Institute, 1275 York Ave, New York, NY 10065, USA
| | - Gabsang Lee
- Developmental Biology Program, Sloan-Kettering Institute, 1275 York Ave, New York, NY 10065, USA
| | - Mark J Tomishima
- SKI Stem Cell Research Facility, Sloan-Kettering Institute, 1275 York Ave, New York, NY 10065, USA
| | - Lorenz Studer
- Developmental Biology Program, Sloan-Kettering Institute, 1275 York Ave, New York, NY 10065, USA; Department of Neurosurgery, Sloan-Kettering Institute, 1275 York Ave, New York, NY 10065, USA.
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Challen GA, Boles NC, Chambers SM, Goodell MA. Distinct hematopoietic stem cell subtypes are differentially regulated by TGF-beta1. Cell Stem Cell 2010; 6:265-78. [PMID: 20207229 DOI: 10.1016/j.stem.2010.02.002] [Citation(s) in RCA: 428] [Impact Index Per Article: 30.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2009] [Revised: 11/11/2009] [Accepted: 02/02/2010] [Indexed: 02/06/2023]
Abstract
The traditional view of hematopoiesis has been that all the cells of the peripheral blood are the progeny of a unitary homogeneous pool of hematopoietic stem cells (HSCs). Recent evidence suggests that the hematopoietic system is actually maintained by a consortium of HSC subtypes with distinct functional characteristics. We show here that myeloid-biased HSCs (My-HSCs) and lymphoid-biased HSCs (Ly-HSCs) can be purified according to their capacity for Hoechst dye efflux in combination with canonical HSC markers. These phenotypes are stable under natural (aging) or artificial (serial transplantation) stress and are exacerbated in the presence of competing HSCs. My- and Ly-HSCs respond differently to TGF-beta1, presenting a possible mechanism for differential regulation of HSC subtype activation. This study demonstrates definitive isolation of lineage-biased HSC subtypes and contributes to the fundamental change in view that the hematopoietic system is maintained by a continuum of HSC subtypes, rather than a functionally uniform pool.
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Affiliation(s)
- Grant A Challen
- Stem Cells and Regenerative Medicine Center, Baylor College of Medicine, Houston, TX 77030, USA
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Chambers SM, Fasano CA, Papapetrou EP, Tomishima M, Sadelain M, Studer L. Erratum: Corrigendum: Highly efficient neural conversion of human ES and iPS cells by dual inhibition of SMAD signaling. Nat Biotechnol 2009. [DOI: 10.1038/nbt0509-485a] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Chambers SM, Shaw CA, Gatza C, Fisk CJ, Donehower LA, Goodell MA. Aging hematopoietic stem cells decline in function and exhibit epigenetic dysregulation. PLoS Biol 2008; 5:e201. [PMID: 17676974 PMCID: PMC1925137 DOI: 10.1371/journal.pbio.0050201] [Citation(s) in RCA: 560] [Impact Index Per Article: 35.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2006] [Accepted: 05/21/2007] [Indexed: 12/22/2022] Open
Abstract
Age-related defects in stem cells can limit proper tissue maintenance and hence contribute to a shortened lifespan. Using highly purified hematopoietic stem cells from mice aged 2 to 21 mo, we demonstrate a deficit in function yet an increase in stem cell number with advancing age. Expression analysis of more than 14,000 genes identified 1,500 that were age-induced and 1,600 that were age-repressed. Genes associated with the stress response, inflammation, and protein aggregation dominated the up-regulated expression profile, while the down-regulated profile was marked by genes involved in the preservation of genomic integrity and chromatin remodeling. Many chromosomal regions showed coordinate loss of transcriptional regulation; an overall increase in transcriptional activity with age and inappropriate expression of genes normally regulated by epigenetic mechanisms was also observed. Hematopoietic stem cells from early-aging mice expressing a mutant p53 allele reveal that aging of stem cells can be uncoupled from aging at an organismal level. These studies show that hematopoietic stem cells are not protected from aging. Instead, loss of epigenetic regulation at the chromatin level may drive both functional attenuation of cells, as well as other manifestations of aging, including the increased propensity for neoplastic transformation. Aging is marked by a decline in function of the entire organism. The effect of age on the regenerative capacity of adult stem cells, which should rejuvenate tissues throughout life, is poorly understood. Bone marrow stem cells, also known as hematopoietic stem cells (HSCs), continuously regenerate the cells that comprise the blood, including the immune system, which fails with age. Here, we show that older HSCs were less able to regenerate the blood system than young HSCs. Paradoxically, the HSC number increased concomitantly, leading to no major difference in overall blood production, even though the immune system did exhibit some defects. To determine why these changes occurred, we looked at global patterns of gene expression in young versus old HSC. Stem cells exhibited an elevated inflammatory response and a decline in factors, called chromatin regulators, that orchestrate DNA accessibility and gene expression. Additional evidence supports the idea that loss of overall gene regulation (epigenetic regulation) is a major event during aging. Whereas much of aging research is concentrated on accumulation of mutations in DNA rather than on global regulatory mechanisms, we speculate that these epigenetic changes could drive many of the manifestations of age. This view also may explain the increased incidence of cancer with age. In highly purified hematopoietic stem cells from mice aged 2 to 21 months, gene expression analysis indicates a deficit in function yet an increase in stem cell number with advancing age.
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Affiliation(s)
- Stuart M Chambers
- Program for Cell and Molecular Biology, Baylor College of Medicine, Houston, Texas, United States of America
- Stem Cells and Regenerative Medicine Center, Baylor College of Medicine, Houston, Texas, United States of America
| | - Chad A Shaw
- Stem Cells and Regenerative Medicine Center, Baylor College of Medicine, Houston, Texas, United States of America
- Department of Molecular & Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Catherine Gatza
- Program for Cell and Molecular Biology, Baylor College of Medicine, Houston, Texas, United States of America
- Department of Virology and Microbiology, Baylor College of Medicine, Houston, Texas, United States of America
| | - C. Joseph Fisk
- Department of Molecular & Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Lawrence A Donehower
- Program for Cell and Molecular Biology, Baylor College of Medicine, Houston, Texas, United States of America
- Department of Virology and Microbiology, Baylor College of Medicine, Houston, Texas, United States of America
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas, United States of America
| | - Margaret A Goodell
- Program for Cell and Molecular Biology, Baylor College of Medicine, Houston, Texas, United States of America
- Stem Cells and Regenerative Medicine Center, Baylor College of Medicine, Houston, Texas, United States of America
- Department of Molecular & Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
- Department of Pediatrics, Baylor College of Medicine, Houston, Texas, United States of America
- * To whom correspondence should be addressed. E-mail:
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Abstract
OBJECTIVE To examine the utility of the GnRH (gonadotrophin-releasing hormone) test in the management of patients with pituitary and parapituitary lesions. PATIENTS AND METHODS A 5-year retrospective study of LH (luteinizing hormone) and FSH (follicle stimulating hormone) responses to GnRH test in patients with HP (hypothalamic-pituitary) disease in a regional endocrine centre. Serum LH and FSH concentrations were measured at baseline and at 20 and 60 min after an intravenous bolus of 100 mcg (micrograms) of GnRH. The GnRH responses were categorised by tumour size, tumour type, and gonadal status. RESULTS Of the 104 patients studied, 46 were male and 58 were female. There were 50 normal, 38 subnormal and 16 exaggerated LH responses compared with 34 normal 67 subnormal and three exaggerated responses for FSH. Seventy-four patients (71.2%) were hypogonadal. Normal LH responses were achieved in half of the hypogonadal subjects and normal FSH responses in more than a third. Furthermore, the LH responses were exaggerated in nine hypogonadal patients compared with three for FSH. The GnRH test could not differentiate between pituitary or parapituitary lesions either by size or type of lesion. An exception was the male non-functioning adenoma (NFA) sub-group (10 patients, all were hypopituitary, seven were hypogonadal), which demonstrated significant subnormal LH and FSH responses compared with other male and female tumour type sub-groups. CONCLUSIONS The data from this study indicate that the GnRH test is unhelpful in the clinical assessment of the HP axis in patients with HP disease.
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Affiliation(s)
- N K Chammas
- Endocrine Unit, King's College Hospital, London, SE5 9PJ, UK.
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Kustikova OS, Geiger H, Li Z, Brugman MH, Chambers SM, Shaw CA, Pike-Overzet K, de Ridder D, Staal FJT, von Keudell G, Cornils K, Nattamai KJ, Modlich U, Wagemaker G, Goodell MA, Fehse B, Baum C. Retroviral vector insertion sites associated with dominant hematopoietic clones mark "stemness" pathways. Blood 2006; 109:1897-907. [PMID: 17119121 PMCID: PMC1801061 DOI: 10.1182/blood-2006-08-044156] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Evidence from model organisms and clinical trials reveals that the random insertion of retrovirus-based vectors in the genome of long-term repopulating hematopoietic cells may increase self-renewal or initiate malignant transformation. Clonal dominance of nonmalignant cells is a particularly interesting phenotype as it may be caused by the dysregulation of genes that affect self-renewal and competitive fitness. We have accumulated 280 retrovirus vector insertion sites (RVISs) from murine long-term studies resulting in benign or malignant clonal dominance. RVISs (22.5%) are located in or near (up to 100 kb [kilobase]) to known proto-oncogenes, 49.6% in signaling genes, and 27.9% in other or unknown genes. The resulting insertional dominance database (IDDb) shows substantial overlaps with the transcriptome of hematopoietic stem/progenitor cells and the retrovirus-tagged cancer gene database (RTCGD). RVISs preferentially marked genes with high expression in hematopoietic stem/progenitor cells, and Gene Ontology revealed an overrepresentation of genes associated with cell-cycle control, apoptosis signaling, and transcriptional regulation, including major "stemness" pathways. The IDDb forms a powerful resource for the identification of genes that stimulate or transform hematopoietic stem/progenitor cells and is an important reference for vector biosafety studies in human gene therapy.
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Affiliation(s)
- Olga S Kustikova
- Department of Experimental Hematology, Hannover Medical School, Germany
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20
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Dumble M, Moore L, Chambers SM, Geiger H, Van Zant G, Goodell MA, Donehower LA. The impact of altered p53 dosage on hematopoietic stem cell dynamics during aging. Blood 2006; 109:1736-42. [PMID: 17032926 PMCID: PMC1794064 DOI: 10.1182/blood-2006-03-010413] [Citation(s) in RCA: 187] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
A temporal decline in tissue stem cell functionality may be a key component of mammalian aging. The tumor suppressor p53 has recently been implicated as a potential regulator of aging. We examined age-associated hematopoietic stem cell (HSC) dynamics in mice with varying p53 activities. Reduced p53 activity in p53+/- mice was associated with higher numbers of proliferating hematopoietic stem and progenitor cells in old age compared with aged wild-type (p53+/+) mice. We also assessed HSC dynamics in a p53 mutant mouse model (p53+/m) with higher apparent p53 activity than wild-type mice. The p53 hypermorphic (p53+/m) mice display phenotypes of premature aging. Many aged p53+/m organs exhibit reduced cellularity and atrophy, suggesting defects in stem-cell regenerative capacity. HSC numbers from old p53+/m mice fail to increase with age, unlike those of their p53+/+ and p53+/- counterparts. Moreover, transplantation of 500 HSCs from old p53+/m mice into lethally irradiated recipients resulted in reduced engraftment compared with old wild-type p53+/+ and p53+/- HSCs. Thus, alteration of p53 activity affects stem-cell numbers, proliferation potential, and hematopoiesis in older organisms, supporting a model in which aging is caused in part by a decline in tissue stem cell regenerative function.
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Affiliation(s)
- Melissa Dumble
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX 77030, and Division of Experimental Hematology, Cincinnati Children's Hospital Medical Center, OH, USA
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21
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Bowman TV, McCooey AJ, Merchant AA, Ramos CA, Fonseca P, Poindexter A, Bradfute SB, Oliveira DM, Green R, Zheng Y, Jackson KA, Chambers SM, McKinney-Freeman SL, Norwood KG, Darlington G, Gunaratne PH, Steffen D, Goodell MA. Differential mRNA processing in hematopoietic stem cells. Stem Cells 2005; 24:662-70. [PMID: 16373690 DOI: 10.1634/stemcells.2005-0552] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Hematopoietic stem cells (HSCs) maintain tissue homeostasis by rapidly responding to environmental changes. Although this function is well understood, the molecular mechanisms governing this characteristic are largely unknown. We used a sequenced-based strategy to explore the role of both transcriptional and post-transcriptional regulation in HSC biology. We characterized the gene expression differences between HSCs, both quiescent and proliferating, and their differentiated progeny. This analysis revealed a large fraction of sequence tags aligned to intronic sequences, which we showed were derived from unspliced transcripts. A comparison of the biological properties of the observed spliced versus unspliced transcripts in HSCs showed that the unspliced transcripts were enriched in genes involved in DNA binding and RNA processing. In addition, levels of unspliced message decreased in a transcript-specific fashion after HSC activation in vivo. This change in unspliced transcript level coordinated with increases in gene expression of splicing machinery components. Combined, these results suggest that post-transcriptional regulation is important in HSC activation in vivo.
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Affiliation(s)
- Teresa V Bowman
- Cell and Gene Therapy Center, Baylor College of Medicine, N1030, One Baylor Plaza, Houston, Texas 77030, USA
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22
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Abstract
Hematopoietic stem cells (HSCs) can be isolated from murine bone marrow by their ability to efflux the Hoechst 33342 dye. This method defines an extremely small and hematopoietically potent subset of cells known as the side population (SP). Recent studies suggest that transplanted single SP cells are capable of lymphohematopoietic repopulation at near absolute efficiencies. Here, we carefully reevaluate the hematopoietic potential of individual SP cells and find substantially lower rates of reconstitution. Our strategy involved the cotransplantation of single SP cells along with different populations of competitor cells that varied in their self-renewal capacity. Even with minimized HSC competition, SP cells were only able to reconstitute up to 35% of recipient mice. Furthermore, through immunophenotyping and clonal in vitro assays we find that SP cells are virtually homogeneous. Isolation of HSCs on the basis of Hoechst exclusion and a single cell-surface marker allows enrichment levels similar to that obtained with complex multicolor strategies. Altogether, our results indicate that even an extremely homogeneous HSC population, based on phenotype and dye efflux, cannot reconstitute mice at absolute efficiencies.
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Affiliation(s)
- Fernando D Camargo
- Program in Cell and Molecular Biology and the Center for Cell and Gene Therapy, Baylor College of Medicine, Houston, TX 77098, USA
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23
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Gilbert JA, Miell JP, Chambers SM, McGregor AM, Aylwin SJB. The nadir growth hormone after an octreotide test dose predicts the long-term efficacy of somatostatin analogue therapy in acromegaly. Clin Endocrinol (Oxf) 2005; 62:742-7. [PMID: 15943838 DOI: 10.1111/j.1365-2265.2005.02278.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
OBJECTIVE In the treatment of acromegaly, a 'test dose' of octreotide is recommended prior to the use of depot somatostatin analogue (SSA) therapy. However, there remains no consensus regarding the criteria that predict a response to treatment. The ability to select patients who may benefit most from medical therapy is potentially of great value in clinical practice. The aim of the study was to determine the predictive value of both the nadir GH and the mean GH following an octreotide test dose in identifying patients who subsequently achieved disease remission with depot SSA therapy. Remission was defined as a mean GH < 5 mU/l (< 2 microg/l). DESIGN Retrospective case-control study. PATIENTS A group of 41 patients with acromegaly underwent an octreotide test dose where GH was measured hourly for a total of 6 h following an injection of octreotide 50 microg subcutaneously. Nadir GH and mean GH following the octreotide test dose were determined. Thirty-three patients were subsequently treated with depot SSA therapy and mean GH and IGF-I levels were determined at follow-up. RESULTS The nadir GH demonstrated superior predictive power to that of mean GH across a range of GH cut-off values. A nadir GH < 5 mU/l demonstrated 80% sensitivity and 83% specificity in predicting remission with depot SSA therapy. A nadir GH < 10 mU/l demonstrated 100% sensitivity and 56% specificity. CONCLUSIONS The nadir GH following an octreotide test dose is a useful predictive marker of achieving disease remission with depot SSA therapy used as either a primary or an adjuvant agent.
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Affiliation(s)
- J A Gilbert
- Department of Endocrinology, King's College Hospital, London, UK
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24
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Qyang Y, Chambers SM, Wang P, Xia X, Chen X, Goodell MA, Zheng H. Myeloproliferative Disease in Mice with Reduced Presenilin Gene Dosage: Effect of γ-Secretase Blockage†. Biochemistry 2004; 43:5352-9. [PMID: 15122901 DOI: 10.1021/bi049826u] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Mammalian presenilins (PS) consist of two highly homologous proteins, PS1 and PS2. Because of their indispensable activity in the gamma-secretase cleavage of amyloid precursor protein to generate Abeta peptides, inhibition of PS gamma-secretase activity is considered a potential therapy for Abeta blockage and Alzheimer's disease intervention. However, a variety of other substrates are also subject to PS-dependent processing, and it is thus imperative to understand the consequences of PS inactivation in vivo. Here we report a pivotal role of PS in hematopoiesis. Mice heterozygous for PS1 and homozygous for PS2 (PS1(+/)(-)PS2(-)(/)(-)) developed splenomegaly with severe granulocyte infiltration. This was preceded by an overrepresentation of granulocytic cells in the bone marrow and a greatly increased multipotent granulocyte-monocyte progenitor in the spleen. In contrast, hematopoietic stem cells and T- and B-lymphocytes were not affected. Importantly, treatment of wild-type splenocytes with a gamma-secretase inhibitor directly promoted the granulocyte-macrophage colony-forming unit (GM-CFU). These results establish a critical role of PS in myelopoiesis. Our finding that this activity can be directly modulated by its gamma-secretase activity has important safety implications concerning these inhibitors.
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Affiliation(s)
- Yibing Qyang
- Huffington Center on Aging, Baylor College of Medicine, Houston, Texas 77030, USA
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25
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Abstract
The past 5 years have witnessed an explosion of interest in using adult-derived stem cells for cell and gene therapy. This has been driven by a number of findings, in particular, the possibility that some adult stem cells can differentiate into non-autologous cell types, and also the discovery of multipotential stem cells in adult bone marrow. These discoveries suggested a quasi-alchemical nature of cells derived from adult organs, thus raising new and exciting therapeutic possibilities. Recent data, however, argue against the whole idea of stem cell 'plasticity', and bring into question the therapeutic strategies based upon this concept. Here, we will review the current state of knowledge in the field and discuss some of the clinical implications.
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Affiliation(s)
- F D Camargo
- Interdepartmental Program in Cell and Molecular Biology, Center for Cell and Gene Therapy, Baylor College of Medicine, Houston, TX 77098, USA
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26
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Abstract
• Differential resistance to arsenate (AsO4 3- ) is demonstrated here among populations of the ericoid mycorrhizal fungus Hymenoscyphus ericae isolated from Calluna vulgaris in natural heathland soils and soils contaminated with AsO4 3- . • Isolates (c. 25) of the fungus from each of two As and Cu mine sites, and a natural heathland site, were screened for AsO4 3- and Cu2+ resistance by growing isolates in media containing a range of AsO4 3- and Cu2+ concentrations. • H. ericae populations from the mine sites demonstrated resistance to AsO4 3- compared with the heathland population; the mine-site populations producing significant growth at the highest AsO4 3- concentration (4.67 mol m-3 ), whereas growth of the heathland population was almost completely inhibited. EC50 values for mine-site isolates were estimated to be 5-41-times higher than the heathland population. All isolates produced identical responses to increasing Cu2+ concentrations, with no differences observed between mine-site and heathland isolates. • Populations of H. ericae on the contaminated mine sites have developed adaptive resistance to AsO4 3- . By contrast, Cu2+ resistance appears to be constitutive.
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Affiliation(s)
- J M Sharples
- Mycorrhiza Research Group, School of Science, Food and Horticulture, University of Western Sydney, Parramatta Campus, Locked Bag 1797, PENRITH SOUTH DC, NSW 1797, Australia
- Institute of Terrestrial Ecology, Monks Wood, Abbots Ripton, Huntingdon, Cambridgeshire, PE17 2LS, UK
| | - A A Meharg
- Institute of Terrestrial Ecology, Monks Wood, Abbots Ripton, Huntingdon, Cambridgeshire, PE17 2LS, UK
- present address: Department of Plant and Soil Science, University of Aberdeen, Cruickshank Building, St Machar Drive, Aberdeen, AB24 3UU, Scotland, UK
| | - S M Chambers
- Mycorrhiza Research Group, School of Science, Food and Horticulture, University of Western Sydney, Parramatta Campus, Locked Bag 1797, PENRITH SOUTH DC, NSW 1797, Australia
| | - J W G Cairney
- Mycorrhiza Research Group, School of Science, Food and Horticulture, University of Western Sydney, Parramatta Campus, Locked Bag 1797, PENRITH SOUTH DC, NSW 1797, Australia
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27
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Sharples JM, Meharg AA, Chambers SM, Cairney JW. Mechanism of arsenate resistance in the ericoid mycorrhizal fungus Hymenoscyphus ericae. Plant Physiol 2000; 124:1327-34. [PMID: 11080308 PMCID: PMC59230 DOI: 10.1104/pp.124.3.1327] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2000] [Accepted: 07/27/2000] [Indexed: 05/19/2023]
Abstract
Arsenate resistance is exhibited by the ericoid mycorrhizal fungus Hymenoscyphus ericae collected from As-contaminated mine soils. To investigate the mechanism of arsenate resistance, uptake kinetics for arsenate (H(2)AsO(4)(-)), arsenite (H(3)AsO(3)), and phosphate (H(2)PO(4)(-)) were determined in both arsenate-resistant and -non-resistant H. ericae. The uptake kinetics of H(2)AsO(4)(-), H(3)AsO(3), and H(2)PO(4)(-) in both resistant and non-resistant isolates were similar. The presence of 5.0 microM H(2)PO(4)(-) repressed uptake of H(2)AsO(4)(-) and exposure to 0.75 mM H(2)AsO(4)(-) repressed H(2)PO(4)(-) uptake in both H. ericae. Mine site H. ericae demonstrated an enhanced As efflux mechanism in comparison with non-resistant H. ericae and lost approximately 90% of preloaded cellular As (1-h uptake of 0.22 micromol g(-1) dry weight h(-1) H(2)AsO(4)(-)) over a 5-h period in comparison with non-resistant H. ericae, which lost 40% of their total absorbed H(2)AsO(4)(-). As lost from the fungal tissue was in the form of H(3)AsO(3). The results of the present study demonstrate an enhanced H(3)AsO(3) efflux system operating in mine site H. ericae as a mechanism for H(2)AsO(4)(-) resistance. The ecological significance of this mechanism of arsenate resistance is discussed.
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Affiliation(s)
- J M Sharples
- Mycorrhiza Research Group, School of Science, University of Western Sydney, P.O. Box 10, Kingswood NSW 2747, Australia
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Sharples JM, Chambers SM, Meharg AA, Cairney JWG. Genetic diversity of root-associated fungal endophytes from Calluna vulgaris at contrasting field sites. New Phytol 2000; 148:153-162. [PMID: 33863033 DOI: 10.1046/j.1469-8137.2000.00734.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
A total of 107 putative ericoid mycorrhizal endophytes were isolated from hair roots of Calluna vulgaris from two abandoned arsenic/copper mine sites and a natural heathland site in southwest England. The endophytes were initially grouped as 14 RFLP types, based on the results of ITS-RFLP analysis using the restriction endonucleases Hinf I, Rsa I and Hae III. ITS sequences were obtained for representative isolates from each RFLP type and compared phylogenetically with sequences for known ericoid mycorrhizal endophytes and selected ascomycetes. The majority of endophyte isolates (62-92%) from each site were identified as Hymenoscyphus ericae, but a number of other less common mycorrhizal RFLP types were also identified, all of which appear to have strong affinities with the order Leotiales. None of the less common RFLP types was isolated from C. vulgaris at more than one field site. Neighbour-joining analysis indicated similarities between the endophytes from C. vulgaris and mycorrhizal endophytes isolated from other Ericaceae and Epacridaceae hosts in North America and Australia.
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Affiliation(s)
- J M Sharples
- 1 Mycorrhiza Research Group, School of Science, University of Western Sydney, PO Box 10, Kingswood NSW 2747, Australia
| | - S M Chambers
- 1 Mycorrhiza Research Group, School of Science, University of Western Sydney, PO Box 10, Kingswood NSW 2747, Australia
| | - A A Meharg
- 1 Mycorrhiza Research Group, School of Science, University of Western Sydney, PO Box 10, Kingswood NSW 2747, Australia
| | - J W G Cairney
- 1 Mycorrhiza Research Group, School of Science, University of Western Sydney, PO Box 10, Kingswood NSW 2747, Australia
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Francavilla R, Castellaneta SP, Hadzic N, Chambers SM, Portmann B, Tung J, Cheeseman P, Rela M, Heaton ND, Mieli-Vergani G. Prognosis of alpha-1-antitrypsin deficiency-related liver disease in the era of paediatric liver transplantation. J Hepatol 2000; 32:986-92. [PMID: 10898319 DOI: 10.1016/s0168-8278(00)80103-8] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
BACKGROUND/AIM Alpha-1-antitrypsin deficiency (alpha1ATD) is the commonest metabolic disease leading to liver transplantation (LT) in children. Approximately 10-15% of the PiZZ population develops liver disease. Five percent of them will require LT within the first 4 years of life. This study aimed to investigate the prognosis of the liver disease associated with PiZZ alpha1ATD in the era of liver transplantation and to determine predictors of outcome. METHODS We reviewed retrospectively the clinical notes of 97 consecutive patients referred from January 1989, when LT became routinely available in our Unit, to July 1998. RESULTS Of 26 (27%) patients who developed end-stage liver disease, 24 have been transplanted and two are waiting for LT. Twenty-one (81%) of these patients presented with neonatal hepatitis at a median age of 2.1 months. Of 71 (73%) children who have not required LT, 61 (86%) presented with neonatal hepatitis at a median age of 1.6 months. Among infants with neonatal hepatitis who required LT, 18 out of 21 (86%) had jaundice for more than 6 weeks compared with 34 of 61 (56%) who survived without LT (p<0.01). Children requiring LT had higher aspartate aminotransferase (AST) at presentation (p<0.0001) and both higher AST and gamma-glutamyl transferase (GGT) at 6 months (p<0.001), 1-year (p<0.0003) and 5-year (p<0.01) follow up when compared to those who are well without LT. Furthermore, children who developed end-stage liver disease more frequently had severe bile duct reduplication (p<0.01), severe fibrosis (p<0.03) with bridging septa (p<0.02) and established cirrhosis (p<0.04) in the initial liver biopsy. Ninety-five of the 97 children (98%) are currently alive; two died after LT. CONCLUSIONS The advent of liver transplantation has significantly improved the prognosis of liver disease associated with PiZZ alpha1ATD. Duration of jaundice, severity of histological features and biochemical abnormalities predict outcome at an early stage of the disease.
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Affiliation(s)
- R Francavilla
- Department of Child Health, King's College Hospital, London, UK
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30
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Affiliation(s)
- J M Sharples
- Mycorrhiza Research Group, School of Science, University of Western Sydney, New South Wales, Australia
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31
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Maeder C, Beaudoin GM, Hsu E, Escobar VA, Chambers SM, Kurtin WE, Bushey MM. Measurement of bilirubin partition coefficients in bile salt micelle/aqueous buffer solutions by micellar electrokinetic chromatography. Electrophoresis 2000; 21:706-14. [PMID: 10733210 DOI: 10.1002/(sici)1522-2683(20000301)21:4<706::aid-elps706>3.0.co;2-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The partition coefficients for the distribution of bilirubin between aqueous phosphateborate buffer and cholic, taurocholic, taurodeoxycholic, and taurochenodeoxycholic micelles have been measured by micellar electrokinetic chromatography at pH 8.5. Determination of the partition coefficients required that the critical micelle concentration and partial specific volumes be determined for each bile salt. Critical micelle concentrations were slightly higher for the trihydroxy bile salts. Partial specific volumes of the bile salt micelles differed very little from each other, and for each bile salt they were constant over the concentration range studied, which was typically from slightly above the critical micelle concentration to 35 mM. Capacity factors were corrected for the effects of applied voltage by extrapolation of the capacity factor to zero applied volts. The free solution mobility of bilirubin, determined in the absence of bile salt, was also corrected for the effects of applied voltage. Plots of extrapolated capacity factor versus phase ratio yield the partition coefficient as the slope of a linear fit to the data. Partition coefficients for bilirubin were significantly higher for dihydroxy bile salts than for trihydroxy bile salts.
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Affiliation(s)
- C Maeder
- Department of Chemistry, Trinity University, San Antonio, TX 78212, USA
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Ambrose HJ, Chambers SM, Mieli-Vergani G, Ferrie R, Newton CR, Robertson NH. Molecular characterization of a new alpha-1-antitrypsin M variant allele, Mwhitstable: implications for DNA-based diagnosis. Diagn Mol Pathol 1999; 8:205-10. [PMID: 10617277 DOI: 10.1097/00019606-199912000-00006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The mother and second child from a family, already with one PI ZZ child, were typed PI MZ by isoelectric focusing and unexpectedly as PI ZZ using a commercial alpha-1-antitrypsin genotyping kit. Both methods typed the father and first child as PI MZ and PI ZZ, respectively. DNA sequence analysis identified a 26-base pair (bp) deletion and 2-bp insertion in intron IV of the normal PI*M allele from both the mother and second child. The majority of the binding site for an amplification primer of the genotyping kit was absent in the variant deletion-insertion allele. The apparent PI*Z/PI*Z genotype of the mother and second child therefore arose from amplification of the PI*Z allele alone. Two hundred random DNA samples were subsequently examined and 5 of these were found to be heterozygous for the same deletion-insertion allele. The authors have designated the previously undescribed PI*M allele that harbors this benign polymorphism PI*Mwhitstable. The genotyping kit has been redesigned and revalidated, and its performance is not affected by the presence of the PI*Mwhitstable allele. The Gen Bank accession number for the nucleotide sequence described is AF159454.
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Affiliation(s)
- H J Ambrose
- AstraZeneca Diagnostics, Northwich, Cheshire, UK
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Abstract
Cystic fibrosis is a common disease of the Caucasian population and is associated with significant early mortality. We present a simple and rapid method for cystic fibrosis genotyping from filter paper blood spots, using a currently available commercial genotyping kit. Using multiplex technology, genotype information on the four most common UK mutations can easily be obtained within a single working day. Used in conjunction with current immunoreactive typsinogen screening protocols, blood spot genotyping offers a method of hastening the diagnosis, and thus treatment, of cystic fibrosis.
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Affiliation(s)
- K H Poyser
- Department of Clinical Biochemistry, King's College Hospital, Denmark Hill, London, UK
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Morris BJ, Chambers SM. Hypothesis: glucagon receptor glycine to serine missense mutation contributes to one in 20 cases of essential hypertension. Clin Exp Pharmacol Physiol 1996; 23:1035-7. [PMID: 8977155 DOI: 10.1111/j.1440-1681.1996.tb01164.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
1. A missense mutation leading to reduced ligand affinity in the glucagon receptor (GCG-R) has been found recently to be five-fold more common in essential hypertensives than normotensives. The present paper provides additional information on patients that harbour this variant and proposes a possible mechanism by which this may lead to hypertension. 2. The seven hypertensives with the mutation were all female, had a later age of onset of the disease and a slightly higher body mass index. 3. Glucagon is involved in the regulation of fluid and electrolyte excretion. Mutant GCG-R results in reduced ligand affinity and cAMP response which, in the kidney, would reduce the normal natriuretic effect of glucagon. This could lead to enhanced fluid reabsorption, expansion of extracellular fluid volume and hypertension via long-term autoregulation of blood pressure.
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Affiliation(s)
- B J Morris
- Department of Physiology and Institute for Biomedical Research, The University of Sydney, New South Wales, Australia
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Cleare AJ, McGregor A, Chambers SM, Dawling S, O'Keane V. Thyroxine replacement increases central 5-hydroxytryptamine activity and reduces depressive symptoms in hypothyroidism. Neuroendocrinology 1996; 64:65-9. [PMID: 8811668 DOI: 10.1159/000127099] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Hypothyroidism is associated with both reduced central 5-HT function and an increased incidence of depression. This study tested the hypothesis that the reduced 5-HT function returns to normal with thyroxine replacement therapy. Seven hypothyroid patients were tested before and after adequate thyroxine replacement. Cortisol and prolactin responses to d-fenfluramine, a centrally acting 5-HT-releasing agent, were used as an index of central (hypothalamic) 5-HT responsiveness. 5-HT-mediated cortisol responses were significantly higher after thyroxine replacement. Basal prolactin levels were reduced, but 5-HT-mediated prolactin responses were not significantly higher after treatment, perhaps due to the pre-treatment responses being elevated by the direct stimulatory effects of hypothyroidism itself on pituitary prolactin secretion. Depressive symptomatology improved with thyroxine. TSH levels were positively related to depressive symptomatology, and inversely to cortisol responses. Depressive symptomatology was inversely related to cortisol responses. These findings thus provide further support that central 5-HT neurotransmission is affected by hypothyroidism. They also suggest that the reduction in 5-HT responsiveness is reversible with thyroxine replacement therapy.
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Affiliation(s)
- A J Cleare
- Department of Psychological Medicine, Institute of Psychiatry, London, UK
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Devlin J, Dunne JB, Sherwood RA, Chambers SM, Tan KC, Peters TJ, Williams R. Relationship between early liver graft viability and enzyme activities in effluent preservation solution. Transplantation 1995; 60:627-31. [PMID: 7570966 DOI: 10.1097/00007890-199510150-00001] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Determination of cellular enzyme activities in washout preservation solution used in hypothermic liver graft storage may allow development of an index that could be clinically valuable in prediction of early post-transplant graft function. In the present study, we collected washed out preservation fluid at the time of graft rinsing from 53 liver recipients. Aspartate aminotransferase and, to a lesser extent, lactate dehydrogenase levels correlated with early postoperative graft viability as assessed by 1-month graft survival and standard biochemical indices of liver function. Those patients with the highest aspartate aminotransferase activity in the washout preservation solution experienced the highest levels of this enzyme postoperatively (area-under-the-curve day 1-3; 1340 vs. 788 IU/L), total bilirubin (area-under-the-curve day 1-5; 901 vs. 538 mumol/L), and rejection frequency (67% vs. 31%) (all P < 0.05), with a significantly lower 1-month graft survival rate compared with patients with low effluent levels (62% vs. 92%, P < 0.05). Two markers of endothelial cell damage, purine nucleoside phosphorylase and a creatine kinase isoenzyme, measured in the fluid did not correlate with early graft viability. It is suggested that assay of aspartate aminotransferase activities in preservation fluid washout samples is a clinically useful indicator of graft viability.
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Affiliation(s)
- J Devlin
- Institute of Liver Studies, King's College School of Medicine and Dentistry, London, United Kingdom
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Chambers SM. Rare-earth imaging. South Hosp 1984; 52:80, 82. [PMID: 10267562] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/13/2023]
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Renwick AG, Soon CY, Chambers SM, Brown CR. Estradiol-17 beta dehydrogenase from chicken liver. J Biol Chem 1981; 256:1881-7. [PMID: 6936398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
NADP+-linked estradiol-17 beta dehydrogenase has been purified 300- to 400-fold from cell-free extracts of chicken liver in a 20 to 30% yield by ammonium sulfate precipitation, ion exchange chromatography, and gel filtration. The enzyme is stable for at least 3 months when stored at -20 degrees C in buffer containing glycerol (50%, v/v). Two forms, with molecular weights of 43,000 and 97,000 are present; these show one major band (Rm = 0.27) and one minor band (Rm = 0.25) on polyacrylamide disc gel electrophoresis. (Rm is defined as the ratio of the distance migrated by the protein band to that of the tracking dye.) The species of lower molecular weight is the more active, with apparent Km values for estradiol-17 beta of 25 and 17.3 microM in the presence and absence, respectively, of bovine serum albumin in the assay medium. The apparent Km for NADP+ is 7.7 microM, and the optimum pH for dehydrogenation is 9.9. The lower molecular weight form has a lambda max at 280 nm, a shoulder at 290 nm, and an A 1% 1 cm of 12.1 at 280 nm. The fluorescence spectrum corresponds to that of a tryptophan-containing protein with lambda max at 288 nm. Isoelectric focusing in gel at pH 5 to 8 shows three major bands of pI 6.9, 6.8, and 6.0. Cross-linking with dimethyl suberimidate followed by electrophoresis reveals five bands. The enzyme is affected by thio reagents and possesses no associated estradiol-sensitive transhydrogenase activity.
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Rhoton AL, Hardy DG, Chambers SM. Microsurgical anatomy and dissection of the sphenoid bone, cavernous sinus and sellar region. Surg Neurol 1979; 12:63-104. [PMID: 451866] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The topographic and internal anatomy of the sphenoid bone is reviewed with an emphasis on the relationships important to the transcranial and subcranial surgical approaches to the sphenoid sinus, sella turcica and cavernous sinus. A stepwise method of study and dissection is outlined. The equipment and materials needed for sphenoid bone dissection in the laboratory are reviewed.
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Abstract
The chromatographic behaviour of an avian oestradiol-17 beta dehydrogenase, the 3(17) beta-hydroxy steroid dehydrogenase from Pseudomonas testosteroni and cortisone reductase from Streptomyces dehydrogenans was studied on columns of p-(phenoxypropoxy)aniline attached to CNBr-activated Sepharose. The ligand was effective in adsorbing the oestradiol dehydrogenase from a partially purified extract of chicken liver, and the cortisone reductase was perferentially retained when mixtures of the three dehydrogenases were applied to columns in 10mM-buffer. Under these conditions the 3(17)beta-hydroxy steroid dehydrogenase was eluted in the front, but was adsorbed in the presence of 3 M-KCl. beta-N-Acetylglucosaminidase present in the liver preparation was not retained by the ligand, whereas lactate dehydrogenase from rabbit muscle was adsorbed in a manner similar to the retention pattern found on affinity chromatography with 2',5'-ADP--Sepharose. The mean overall purification of the oestradiol dehydrogenase was 13-fold, with a mean recovery of 53%. p-(Phenoxypropoxy)aniline offers promise for the purification of steroid-transforming enzymes where elution with substrate or cofactor is not wanted. It is also suggested that the ligand may be of service in the purification of receptors of hormonal steroids.
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Abstract
✓ The increasing use of the transsphenoidal approach to sellar tumors has created a need for more detailed information about the neurovascular relationships of the sphenoid sinus. To better define this anatomy, 25 sphenoid sinuses were examined in cadavers, with attention to the neural and vascular structures in the lateral wall of the sinus. Three structures produced prominent bulges into the lateral wall of the sinus; they were 1) the optic nerves, 2) the carotid arteries, and 3) the maxillary branches of the trigeminal nerve. Over half of these structures had a bone thickness of less than 0.5 mm separating them from the sphenoid sinus, and in a few cases, they were separated by only sinus mucosa and dura.
1) The optic canals protruded into the superolateral part of the sphenoid sinus in all except one side of one specimen. In 4% of the optic nerves, only the optic sheath and sinus mucosa separated the nerves from the sinus, and in 78%, less than a 0.5-mm thickness of bone separated them. 2) The carotid arteries produced a prominent bulge into the sphenoid sinus in all but one side of one specimen. In 8% of the carotid arteries there were areas where no bone separated the artery and the sinus. 3) The maxillary branches of trigeminal nerves bulged into the inferolateral part of the sphenoid sinus in all except one side of two specimens. One side of one specimen had no bone, and 70% had less than a 0.5-mm thickness of bone separating the nerve from the sinus. The importance of these findings in transsphenoidal surgery is reviewed.
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Abstract
Under conditions of serial recall of auditorily presented lists of digits, recall of the last item has been shown to be adversely affected by the presence of a redundant item following the list. This is known as 'the suffix effect' (Crowder & Morton, 1969). In a series of experiments it is shown that the size of this effect is not influenced by the phonological complexity of the suffix. Non-speech sounds, on the other hand, produce no suffix effect even when the subjects are forced to process them. Certain speech sounds were also found to produce no effect. It is concluded that these sounds lacked properties which are characteristic of speech sounds and so were classified as 'non-speech' and that as a result, these sounds are processed by a separate system from the speech sounds.
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Abstract
Subjects were presented with a list of digits to alternate ears for serial recall. The list was followed by a suffix, a redundant acoustic event which did not have to be recalled. The suffix was presented either to one of the ears or binaurally. In all cases the suffix gave rise to a selective impairment of recall of the final items in the list. The results are interpreted as showing first that stimuli of the kind used are processed by simultaneously selecting both ears rather than by switching attention, and second that the site of the suffix effect is after the selection mechanism.
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Tökés ZA, Chambers SM. Proteolytic activity associated with human erythrocyte membranes. Self-digestion of isolated human erythrocyte membranes. Biochim Biophys Acta 1975; 389:325-38. [PMID: 237549 DOI: 10.1016/0005-2736(75)90325-9] [Citation(s) in RCA: 91] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
At least two kinds of enzymes are active in the proteolytic self-digestion of erythrocyte membranes. The specific activities of these enzymes do not decrease with repeated washings of purified stroma. The effects of a variety of inhibitors on the membrane preparation's capacity to digest 125-I-labelled casein, covalently linked to latex beads, have been examined. Pepstatin-inhibitable enzyme, active at low pH, digests the membrane extensively to small polypeptide fragments. Spectrin, located at the internal part of the membrane, is readily degraded. Diisopropylfluorophosphate-inhibitable enzyme, active at pH 8-9, has only limited digestive capacity. Some of the membrane components, such as the small molecular weight glycoproteins, are resistant to digestion. The restricted capacity of digestion is due to the membrane molecular arrangement; increased disaggregation removes the restriction and increases the activity. Spectrin is not digested unless the membrane topography is disrupted by NP-40 neutral detergent. These observations suggest that the enzymes active at basic pH are located external to the cell. Intact cells do possess a limited capacity to degrade 125-I-labelled casein when their surfaces are brought into contact with substrate-coated beads.
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Tökés ZA, Woon WC, Chambers SM. Digestive enzymes secreted by the carnivorous plant Nepenthes macferlanei L. Planta 1974; 119:39-46. [PMID: 24442407 DOI: 10.1007/bf00390820] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/1974] [Indexed: 05/09/2023]
Abstract
At least two proteases are present in the secretion of the pitchers of Nepenthes macferlanei, a major one with an estimated molecular weight of 59000 and a minor one of 21000. The specificity of the major enzyme, nepenthesin, was broader than previously reported, and strikingly similar to that of pepsin. Lipase activity was also demonstrated, while no amylase activity was present.
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Affiliation(s)
- Z A Tökés
- Department of Biochemistry, University of Malaya, Kuala Lumpur, Malaysia
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