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Richardson RM, Nguyen B, Holt SE, Broaddus WC, Fillmore HL. Ectopic telomerase expression inhibits neuronal differentiation of NT2 neural progenitor cells. Neurosci Lett 2007; 421:168-72. [PMID: 17566647 DOI: 10.1016/j.neulet.2007.03.079] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2006] [Revised: 02/19/2007] [Accepted: 03/30/2007] [Indexed: 11/21/2022]
Abstract
There is significant interest in the potential use of telomerase-immortalized cells in transplantation to replace neurons lost to neurodegenerative diseases and other central nervous system injuries. Neural progenitor cells (NPCs) transduced with human telomerase reverse transcriptase (hTERT), the catalytic component of telomerase, have the potential both to proliferate indefinitely in vitro and to respond to differentiation signals necessary for generating appropriate cells for transplantation. The purpose of this study was to evaluate the differentiation of neurons from NT2 cells, a model NPC cell line, following hTERT transduction. RT-PCR and telomerase activity data demonstrated that persistent exogenous hTERT expression significantly inhibited the differentiation of neurons from NT2 cells. Following retinoic acid induced differentiation, hTERT-NT2 cells produced only one fourth of the neurons generated by parental and vector-control cells. A differentiation-inhibiting effect of constitutive telomerase activity has not been reported previously in other hTERT-transduced progenitor cell lines, implying a unique role for telomerase in the proliferation and differentiation of NPCs that have tumorigenic potential. Elucidating the mechanism responsible for this effect may aid in understanding the potential role of telomerase activity in the tumorigenicity of NPCs, as well as in optimizing the production of safe, telomerase-engineered, transplantable neurons.
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Affiliation(s)
- R Mark Richardson
- Department of Neurosurgery, Medical College of Virginia, Hospitals, Virginia Commonwealth University, VA, USA.
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52
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Chung SA, Wei AQ, Connor DE, Webb GC, Molloy T, Pajic M, Diwan AD. Nucleus pulposus cellular longevity by telomerase gene therapy. Spine (Phila Pa 1976) 2007; 32:1188-96. [PMID: 17495775 DOI: 10.1097/brs.0b013e31805471a3] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
STUDY DESIGN Nonviral transfection of nucleus pulposus cells with a telomerase expression construct to assess the effects on cellular lifespan, function, karyotypic stability, and transformation properties. OBJECTIVES To investigate whether telomerase gene therapy can extend the cellular lifespan while retaining functionality of nucleus pulposus cells in a safe manner. SUMMARY OF BACKGROUND DATA Degeneration of the intervertebral disc is an age-related condition in which cells responsible for the maintenance and health of the disc deteriorate with age. Telomerase can extend the cellular lifespan and function of other musculoskeletal tissues, such as the heart, bones, and connective tissues. Therefore, extension of the cellular lifespan and matrix production of intervertebral disc cells may have the potential to delay the degeneration process. METHODS Ovine nucleus pulposus cells were lipofectamine transfected in vitro with a human telomerase reverse transcriptase (hTERT) expression construct. Cellular lifespan and matrix transcript levels were determined by cumulative population doublings and real-time RT-PCR, respectively. G1-cell cycle checkpoint, p53 functionality, growth of transfected cells in anchorage-independent or serum starvation conditions, and karyotypic analysis were performed. RESULTS Transfection was achieved successfully with 340% +/- 7% (mean +/- SD) relative telomerase activity in hTERT-transfected cells. hTERT transfection enabled a 50% extension in mean cellular lifespan and prolonged matrix production of collagen 1 and 2 for more than 282 days. Karyotypic instability was detected but G1-cell cycle checkpoint and p53 was functionally comparable to parental cells with no growth in serum starvation or anchorage-independent conditions. CONCLUSIONS Telomerase can extend the cellular lifespan of nucleus pulposus cells and prolong the production of extracellular matrix. Safety is still unresolved, as karyotypic instability was detected but no loss of contact inhibition, mitogen dependency, or G1-cell cycle checkpoint control was evident.
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Affiliation(s)
- Sylvia A Chung
- Orthopaedic Research Institute, University of New South Wales, St. George Hospital Campus, NSW, Australia
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53
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Gu G, Yuan J, Wills M, Kasper S. Prostate cancer cells with stem cell characteristics reconstitute the original human tumor in vivo. Cancer Res 2007; 67:4807-15. [PMID: 17510410 DOI: 10.1158/0008-5472.can-06-4608] [Citation(s) in RCA: 261] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Cancer may arise from a cancer stem/progenitor cell that shares characteristics with its normal counterpart. We report the reconstitution of the original human prostate cancer specimen from epithelial cell lines (termed HPET for human prostate epithelial/hTERT) derived from this sample. These tumors can be described in terms of Gleason score, a classification not applied to any of the transgenic mouse models currently developed to mimic human disease. Immunohistochemical and Western blot analyses indicate that they do not express androgen receptor or p63, similar to that reported for prostate stem cells. These cell lines also express embryonic stem markers (Oct4, Nanog, and Sox2) as well as early progenitor cell markers (CD44 and Nestin) in vitro. Clonally derived HPET cells reconstitute the original human tumor in vivo and differentiate into the three prostate epithelial cell lineages, indicating that they arise from a common stem/progenitor cell. Serial transplantation experiments reconstitute the tumors, suggesting that a fraction of parental or clonally derived HPET cells have self-renewal potential. Thus, this model may enhance our understanding of human tumor development and provide a mechanism for studying cancer stem/progenitor cells in differentiation, tumorigenesis, preclinical testing, and the development of drug resistance.
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Affiliation(s)
- Guangyu Gu
- Department of Urologic Surgery, Vanderbilt University Medical Center, Nashville, TN 37232-2765, USA
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54
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Cheng A, Shin-ya K, Wan R, Tang SC, Miura T, Tang H, Khatri R, Gleichman M, Ouyang X, Liu D, Park HR, Chiang JY, Mattson MP. Telomere protection mechanisms change during neurogenesis and neuronal maturation: newly generated neurons are hypersensitive to telomere and DNA damage. J Neurosci 2007; 27:3722-33. [PMID: 17409236 PMCID: PMC6672411 DOI: 10.1523/jneurosci.0590-07.2007] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Telomeres are DNA-protein complexes at the ends of eukaryotic chromosomes that play an important role in maintaining the integrity of the genome. In proliferative stem cells and cancer cells, telomere length is maintained by telomerase, and telomere structure and functions are regulated by telomere-associated proteins. We find that telomerase levels are high in embryonic cortical neural progenitor cells (NPCs) and low in newly generated neurons (NGNs) and mature neurons (MNs). In contrast, telomere repeat-binding factor 2 (TRF2) expression is undetectable in early brain development in vivo and in cultured NPCs and is expressed at progressively higher levels as NPCs cease proliferation and differentiate into postmitotic neurons. The telomere-disrupting agent telomestatin induces a DNA damage response and apoptosis in NGNs (which have low levels of TRF2 and telomerase), whereas NPCs (which have high levels of telomerase) and MNs (which have high levels of TRF2) are resistant to telomere damage. Overexpression of TRF2 in NGNs protects them against death induced by telomestatin and other DNA-damaging agents. Knockdown of TRF2 expression in MNs and knock-out of telomerase reverse transcriptase in NPCs increased their sensitivity to telomere- and DNA-damaging agents but did not affect the vulnerability of NGNs. These findings suggest that TRF2 and telomerase function as distinct telomere protection mechanisms during the processes of neurogenesis and neuronal maturation and that hypersensitivity of NGNs to telomere damage results from relative deficiencies of both telomerase and TRF2.
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Affiliation(s)
- Aiwu Cheng
- Laboratory of Neurosciences, National Institute on Aging Intramural Research Program, Baltimore, Maryland 21224
| | - Kazuo Shin-ya
- Institute of Molecular and Cellular Biosciences, University of Tokyo, Tokyo, 113-8656, Japan
| | - Ruiqian Wan
- Laboratory of Neurosciences, National Institute on Aging Intramural Research Program, Baltimore, Maryland 21224
| | - Sung-chun Tang
- Laboratory of Neurosciences, National Institute on Aging Intramural Research Program, Baltimore, Maryland 21224
- Stroke Center, Neurology Department, National Taiwan University Hospital, Taipei, Taiwan, ROC 100
| | - Takumi Miura
- Laboratory of Neurosciences, National Institute on Aging Intramural Research Program, Baltimore, Maryland 21224
| | - Hongyang Tang
- Laboratory of Neurosciences, National Institute on Aging Intramural Research Program, Baltimore, Maryland 21224
| | - Rina Khatri
- Laboratory of Neurosciences, National Institute on Aging Intramural Research Program, Baltimore, Maryland 21224
| | - Marc Gleichman
- Laboratory of Neurosciences, National Institute on Aging Intramural Research Program, Baltimore, Maryland 21224
| | - Xin Ouyang
- Laboratory of Neurosciences, National Institute on Aging Intramural Research Program, Baltimore, Maryland 21224
| | - Dong Liu
- Laboratory of Neurosciences, National Institute on Aging Intramural Research Program, Baltimore, Maryland 21224
| | - Hae-Rong Park
- Institute of Molecular and Cellular Biosciences, University of Tokyo, Tokyo, 113-8656, Japan
| | - Jeffrey Y. Chiang
- Experimental Immunology Branch, National Cancer Institute, Bethesda, Maryland 20892, and
| | - Mark P. Mattson
- Laboratory of Neurosciences, National Institute on Aging Intramural Research Program, Baltimore, Maryland 21224
- Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205
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55
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Abstract
A new study by Yan and colleagues makes an important contribution to research on human spinal cord stem cells.
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Affiliation(s)
- Natalia Abramova Lowry
- Center for Neuropharmacology and Neuroscience, Albany Medical College, Albany, New York, United States of America.
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56
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Lee HJ, Kim KS, Kim EJ, Choi HB, Lee KH, Park IH, Ko Y, Jeong SW, Kim SU. Brain transplantation of immortalized human neural stem cells promotes functional recovery in mouse intracerebral hemorrhage stroke model. Stem Cells 2007; 25:1204-12. [PMID: 17218400 DOI: 10.1634/stemcells.2006-0409] [Citation(s) in RCA: 166] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
We have generated stable, immortalized cell lines of human NSCs from primary human fetal telencephalon cultures via a retroviral vector encoding v-myc. HB1.F3, one of the human NSC lines, expresses a normal human karyotype of 46, XX, and nestin, a cell type-specific marker for NSCs. F3 has the ability to proliferate continuously and differentiate into cells of neuronal and glial lineage. The HB1.F3 human NSC line was used for cell therapy in a mouse model of intracerebral hemorrhage (ICH) stroke. Experimental ICH was induced in adult mice by intrastriatal administration of bacterial collagenase; 1 week after surgery, the rats were randomly divided into two groups so as to receive intracerebrally either human NSCs labeled with beta-galactosidase (n = 31) or phosphate-buffered saline (PBS) (n = 30). Transplanted NSCs were detected by 5-bromo-4-chloro-3-indolyl-beta-d-galactoside histochemistry or double labeling with beta-galactosidase (beta-gal) and mitogen-activated protein (MAP)2, neurofilaments (both for neurons), or glial fibrillary acidic protein (GFAP) (for astrocytes). Behavior of the animals was evaluated for period up to 8 weeks using modified Rotarod tests and a limb placing test. Transplanted human NSCs were identified in the perihematomal areas and differentiated into neurons (beta-gal/MAP2(+) and beta-gal/NF(+)) or astrocytes (beta-gal/GFAP(+)). The NSC-transplanted group showed markedly improved functional performance on the Rotarod test and limb placing after 2-8 weeks compared with the control PBS group (p < .001). These results indicate that the stable immortalized human NSCs are a valuable source of cells for cell replacement and gene transfer for the treatment of ICH and other human neurological disorders. Disclosure of potential conflicts of interest is found at the end of this article.
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Affiliation(s)
- Hong J Lee
- Division of Neurology, Department of Medicine, University of British Columbia Hospital, University of British Columbia, Vancouver, British Columbia V6T 2B5, Canada.
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57
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Fleisig HB, Wong JMY. Telomerase as a clinical target: Current strategies and potential applications. Exp Gerontol 2007; 42:102-12. [PMID: 16814507 DOI: 10.1016/j.exger.2006.05.011] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2006] [Accepted: 05/05/2006] [Indexed: 01/19/2023]
Abstract
Chromosome ends are capped by telomeres, protective DNA-protein complexes that distinguish natural ends from random DNA breaks. Telomeres erode with each successive cell division, and such divisions cease once telomeres become critically short. This proliferation limit is important as a tumor suppressive mechanism, but also contributes to the degenerative conditions associated with cellular aging. In cell types that require continuous renewal, transient expression of telomerase delays proliferation arrest by the de novo synthesis of telomere repeats. Data from our work and others' has shown that deficient telomerase activity has a negative impact on normal human physiology. In the bone marrow failure syndrome dyskeratosis congenita, telomerase enzyme deficiency leads to the premature shortening of telomeres. Premature telomere shortening most grievously affects tissues that have a rapid turnover, such as the hematopoietic and epithelial compartments. In the most severe cases, compromised renewal of hematopoietic stem cells leads to bone marrow failure and premature death. Telomerase activation/replacement shows potential as a therapy for telomere maintenance deficiency syndromes, and in tissue engineering for the degenerative conditions that are associated with normal aging. Conversely, clinical researchers are developing telomerase inhibition therapies to treat tumors, which overcome the short-telomere barrier to unrestricted proliferation by over-expressing telomerase.
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Affiliation(s)
- Helen B Fleisig
- Division of Pharmacology and Toxicology, Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, BC, Canada V6T 1Z3
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58
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Lim DA, Huang YC, Alvarez-Buylla A. The Adult Neural Stem Cell Niche: Lessons for Future Neural Cell Replacement Strategies. Neurosurg Clin N Am 2007; 18:81-92, ix. [PMID: 17244556 DOI: 10.1016/j.nec.2006.10.002] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Transplantation of neural stem cells (NSCs) and the mobilization of endogenous neural precursors in the adult brain have been proposed as therapies for a wide range of central nervous system disorders, including neurodegenerative disease (eg, Parkinson's disease), demyelinating disorders (eg, multiple sclerosis), stroke, and trauma. Although there is great hope for the success of such therapies, the clinical development of NSC-based therapies is still in its infancy. A greater understanding of how to control the proliferation, migration, differentiation, and survival of NSCs and their progeny is critical for the development of cell replacement therapies. NSCs are partially regulated by the specialized microenvironment--or "niche"--in which these cells reside. The adult rodent brain retains NSCs in two separate niches that continually generate new neurons: the subventricular zone (SVZ) of the lateral ventricle and the dentate gyrus subgranular zone (SGZ) of the hippocampus. Similar niches may be found in the human brain. In tis article, the authors briefly review their current understanding of the SVZ and SGZ niches. Lessons learned from these niches may allow one to manipulate NSCs better in culture for therapeutic transplantation and possibly even to mobilize endogenous precursors to repair diseased or injured brain.
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Affiliation(s)
- Daniel A Lim
- Department of Neurological Surgery, University of California, San Francisco, 505 Parnassus Street, M779, Box 0112, San Francisco, CA 94143, USA.
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59
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Wang S, Hu C, Zhu J. Transcriptional silencing of a novel hTERT reporter locus during in vitro differentiation of mouse embryonic stem cells. Mol Biol Cell 2006; 18:669-77. [PMID: 17151355 PMCID: PMC1783791 DOI: 10.1091/mbc.e06-09-0840] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
The human telomerase reverse transcriptase hTERT is highly expressed in undifferentiated embryonic cells and silenced in the majority of somatic cells. To investigate the mechanisms of hTERT silencing, we have developed a novel reporter using a bacterial artificial chromosome (BAC) that contained the entire hTERT gene and its neighboring loci, hCRR9 and hXtrp2. Firefly and Renilla luciferases were used to monitor transcription from the hTERT and hCRR9 promoters, respectively. In mouse embryonic stem cells stably integrated with the BAC reporter, both hTERT and hCRR9 promoters were highly expressed. Upon differentiation into embryoid bodies and further into mineral-producing osteogenic cells, the hTERT promoter activity decreased progressively, whereas the hCRR9 promoter remained highly active, both resembling their endogenous counterparts. In fully differentiated cells, the hTERT promoter was completely silenced and adopted a chromatin structure that was similar to its native counterpart in human cells. Inhibition of histone deacetylases led to the opening of the hTERT promoter and partially relieved repression, suggesting that histone deacetylation was necessary but not sufficient for hTERT silencing. Thus, our result demonstrated that developmental silencing of the human TERT locus could be recapitulated in a chromosomal position-independent manner during the differentiation of mouse embryonic stem cells.
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MESH Headings
- Acetylation
- Animals
- Cell Differentiation/genetics
- Cells, Cultured
- Chromosomes, Artificial, Bacterial/genetics
- Embryonic Stem Cells/cytology
- Embryonic Stem Cells/enzymology
- Gene Expression Regulation, Developmental
- Gene Silencing
- Genes, Reporter
- Histones/metabolism
- Humans
- Mice
- Mice, Transgenic
- Models, Biological
- Promoter Regions, Genetic
- Receptors, CCR
- Receptors, Chemokine/genetics
- Telomerase/genetics
- Transcription, Genetic
- Transgenes
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Affiliation(s)
- Shuwen Wang
- Department of Cellular and Molecular Physiology, Pennsylvania State University College of Medicine, Hershey, PA 17033
| | - Chunguang Hu
- Department of Cellular and Molecular Physiology, Pennsylvania State University College of Medicine, Hershey, PA 17033
| | - Jiyue Zhu
- Department of Cellular and Molecular Physiology, Pennsylvania State University College of Medicine, Hershey, PA 17033
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60
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Liu JP, Cassar L, Pinto A, Li H. Mechanisms of cell immortalization mediated by EB viral activation of telomerase in nasopharyngeal carcinoma. Cell Res 2006; 16:809-17. [PMID: 17016469 DOI: 10.1038/sj.cr.7310098] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Nasopharyngeal carcinoma (NPC) is a common cancer in Southern China and Southeast Asia. The disease is a poorly differentiated carcinoma without effective cure, and the mechanism underlying its development remains largely unknown. Of several factors identified in NPC aetiology in recent years, Epstein-Barr virus (EBV) infection has emerged to be most important. In almost all NPC cells, EBV uses several intracellular mechanisms to cause oncogenic evolution of the infected cells. One such mechanism by which EBV infection induces cellular immortalization is believed to be through the activation of telomerase, an enzyme that is normally repressed but becomes activated during cancer development. Studies show that greater than 85% of primary NPC display high telomerase activity by mechanisms involving EBV infection, consistent with the notion that EBV is commonly involved in inducing cell immortalization. More recently, different EBV proteins have been shown to activate or inhibit the human telomerase reverse transcriptase gene, by modulating intracellular signalling pathways. These findings suggest a new model with a number of challenges towards our understanding, molecular targeting and therapeutic intervention in NPC.
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Affiliation(s)
- Jun-Ping Liu
- Department of Immunology, Central Eastern Clinical School, Monash University, AMREP, Commercial Road, Prahran, Melbourne, Victoria 3181, Australia.
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61
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Cacci E, Villa A, Parmar M, Cavallaro M, Mandahl N, Lindvall O, Martinez-Serrano A, Kokaia Z. Generation of human cortical neurons from a new immortal fetal neural stem cell line. Exp Cell Res 2006; 313:588-601. [PMID: 17156776 DOI: 10.1016/j.yexcr.2006.11.001] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2006] [Revised: 10/30/2006] [Accepted: 11/01/2006] [Indexed: 01/17/2023]
Abstract
Isolation and expansion of neural stem cells (NSCs) of human origin are crucial for successful development of cell therapy approaches in neurodegenerative diseases. Different epigenetic and genetic immortalization strategies have been established for long-term maintenance and expansion of these cells in vitro. Here we report the generation of a new, clonal NSC (hc-NSC) line, derived from human fetal cortical tissue, based on v-myc immortalization. Using immunocytochemistry, we show that these cells retain the characteristics of NSCs after more than 50 passages. Under proliferation conditions, when supplemented with epidermal and basic fibroblast growth factors, the hc-NSCs expressed neural stem/progenitor cell markers like nestin, vimentin and Sox2. When growth factors were withdrawn, proliferation and expression of v-myc and telomerase were dramatically reduced, and the hc-NSCs differentiated into glia and neurons (mostly glutamatergic and GABAergic, as well as tyrosine hydroxylase-positive, presumably dopaminergic neurons). RT-PCR analysis showed that the hc-NSCs retained expression of Pax6, Emx2 and Neurogenin2, which are genes associated with regionalization and cell commitment in cortical precursors during brain development. Our data indicate that this hc-NSC line could be useful for exploring the potential of human NSCs to replace dead or damaged cortical cells in animal models of acute and chronic neurodegenerative diseases. Taking advantage of its clonality and homogeneity, this cell line will also be a valuable experimental tool to study the regulatory role of intrinsic and extrinsic factors in human NSC biology.
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Affiliation(s)
- E Cacci
- Laboratory of Neural Stem Cell Biology, Section of Restorative Neurology, Lund Strategic Research Center for Stem Cell Biology and Cell Therapy, BMC B10, Klinikgatan 26, University Hospital, SE-221 84 Lund, Sweden
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62
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Nayak MS, Kim YS, Goldman M, Keirstead HS, Kerr DA. Cellular therapies in motor neuron diseases. Biochim Biophys Acta Mol Basis Dis 2006; 1762:1128-38. [PMID: 16872810 DOI: 10.1016/j.bbadis.2006.06.004] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2006] [Revised: 05/28/2006] [Accepted: 06/08/2006] [Indexed: 12/13/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) and spinal muscular atrophy (SMA) are prototypical motor neuron diseases that result in progressive weakness as a result of motor neuron dysfunction and death. Though much work has been done in both diseases to identify the cellular mechanisms of motor neuron dysfunction, once motor neurons have died, one of potential therapies to restore function would be through the use of cellular transplantation. In this review, we discuss potential strategies whereby cellular therapies, including the use of stem cells, neural progenitors and cells engineered to secrete trophic factors, may be used in motor neuron diseases. We review pre-clinical data in rodents with each of these approaches and discuss advances and regulatory issues regarding the use of cellular therapies in human motor neuron diseases.
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Affiliation(s)
- Mamatha S Nayak
- Department of Neurology, Johns Hopkins University School of Medicine, 600 North Wolfe Street, Baltimore, MD 21287, USA
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63
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Roy NS, Cleren C, Singh SK, Yang L, Beal MF, Goldman SA. Functional engraftment of human ES cell-derived dopaminergic neurons enriched by coculture with telomerase-immortalized midbrain astrocytes. Nat Med 2006; 12:1259-68. [PMID: 17057709 DOI: 10.1038/nm1495] [Citation(s) in RCA: 597] [Impact Index Per Article: 33.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2006] [Accepted: 09/15/2006] [Indexed: 02/07/2023]
Abstract
To direct human embryonic stem (HES) cells to a dopaminergic neuronal fate, we cocultured HES cells that were exposed to both sonic hedgehog and fibroblast growth factor 8 with telomerase-immortalized human fetal midbrain astrocytes. These astrocytes substantially potentiated dopaminergic neurogenesis by both WA09 and WA01 HES cells, biasing them to the A9 nigrostriatal phenotype. When transplanted into the neostriata of 6-hydroxydopamine-lesioned parkinsonian rats, the dopaminergic implants yielded a significant, substantial and long-lasting restitution of motor function. However, although rich in donor-derived tyrosine hydroxylase-expressing neurons, the grafts exhibited expanding cores of undifferentiated mitotic neuroepithelial cells, which can be tumorigenic. These results show the utility of recreating the cellular environment of the developing human midbrain while driving dopaminergic neurogenesis from HES cells, and they demonstrate the potential of the resultant cells to mediate substantial functional recovery in a model of Parkinson disease. Yet these data also mandate caution in the clinical application of HES cell-derived grafts, given their potential for phenotypic instability and undifferentiated expansion.
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Affiliation(s)
- Neeta S Roy
- Department of Neurology, Weill Medical College of Cornell University, New York, New York 10021, USA.
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64
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Abstract
Diseases of the brain and spinal cord represent especially daunting challenges for cell-based strategies of repair, given the multiplicity of cell types within the adult central nervous system, and the precision with which they must interact in both space and time. Nonetheless, a number of diseases are especially appropriate for cell-based therapy, in particular those in which single phenotypes are lost, and in which the re-establishment of vectorially specific connections is not entirely requisite for therapeutic benefit. We review here a set of potential therapeutic indications that meet these criteria as potentially benefiting from the transplantation of neural stem and progenitor cells. These include: (i) transplantation of phenotypically restricted neuronal progenitor cells into diseases of a single neuronal phenotype, such as Parkinson's disease; (ii) implantation of mixed progenitor pools into diseases characterized by the loss of a limited number of discrete phenotypes, such as spinal cord injury and the motor neuronopathies; (iii) transplantation of glial and nominally oligodendrocytic progenitor cells as a means of treating disorders of myelin; and (iv) transplantation of neural stem cells as a means of treating lysosomal storage disorders and other diseases of enzymatic deficiency. Among the diseases potentially approachable by these strategies, the myelin disorders, including the paediatric leucodystrophies as well as adult traumatic and inflammatory demyelinations, may present the most compelling targets for cell-based neurological therapy.
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Affiliation(s)
- Steven A Goldman
- Division of Cell and Gene Therapy, Department of Neurology, University of Rochester Medical Center, 601 Elmwood Avenue, PO Box 645, Rochester, NY 14642, USA.
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65
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Serakinci N, Keith WN. Therapeutic potential of adult stem cells. Eur J Cancer 2006; 42:1243-6. [PMID: 16678403 DOI: 10.1016/j.ejca.2006.01.036] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2006] [Accepted: 01/23/2006] [Indexed: 01/14/2023]
Abstract
The aim of cell-based therapies is to replace or repair damaged tissues and organs. A diverse number of disorders are amenable to this approach, including haematopoietic, neurological and cardiovascular diseases, as well as bone defects and diabetes. Central to the success of cell therapy is the necessity to be able to identify, select, expand and manipulate cells outside the body. Recent advances in adult stem cell technologies and basic biology have accelerated therapeutic opportunities aimed at eventual clinical applications. Adult stem cells with the ability to differentiate down multiple lineages are an attractive alternative to human embryonic stem cells (hES) in regenerative medicine. In many countries, present legislation surrounding hES cells makes their use problematic, and indeed the origin of hES cells may represent a controversial issue for many communities. However, adult stem cells are not subject to these issues. This review will therefore focus on adult stem cells. Based on their extensive differentiation potential and, in some cases, the relative ease of their isolation, adult stem cells are appropriate for clinical development. Recently, several observations suggest that multipotential adult stem cells are capable of producing a whole spectrum of cell types, regardless of whether or not these tissues are derived from same germ layer; highlighting the opportunity to manipulate stem cells for therapeutic use.
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Affiliation(s)
- Nedime Serakinci
- Department of Anatomy and Neurobiology, I Southern Denmark University, Institute of Medical Biology, Winsløwparken 21 Stuen,C 5000 Odense, Denmark.
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66
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Liu X, Zhu Y, Gao W. Isolation of neural stem cells from the spinal cords of low temperature preserved abortuses. J Neurosci Methods 2006; 157:64-70. [PMID: 16682082 DOI: 10.1016/j.jneumeth.2006.03.025] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2005] [Revised: 12/27/2005] [Accepted: 03/31/2006] [Indexed: 10/24/2022]
Abstract
In the present study, we show that neural stem cells can be obtained from the spinal cords of low temperature preserved abortuses. Fourteen weeks old abortuses were stored in a refrigerator at 4 degrees C for 2 h, 6 h and 12 h before use. Neural stem cells were isolated from cervical cord, thoracic cord and lumbar/sacral cord separately and induced to differentiate with fetal bovine serum. Clonal culture was carried out to demonstrate that the isolated cells met the standard of stem cells. Fluorescent immunocytochemistry was used to examine the expression of neural stem cell marker (nestin), neuronal marker (MAP2), astrocyte marker (GFAP) and cholinergic marker (ChAT). The stem cells in different cultures were compared. As a result, neural stem cells were obtained from all the spinal cord segments with different postmortem intervals. The lumbar/sacral cord cultures gave rise to the most abundant primary neurospheres. When the preservation was prolonged to 12 h, the number of primary neurospheres decreased sharply. Neurospheres in all cultures showed nestin positive immunoreactivity and could yield astrocytes and neurons including cholinergic neurons in differential cultures. The clonal formation and phenotype capacity were similar in all cultures. In conclusion, spinal neural stem cells can be isolated from low temperature preserved abortuses and represent an alternative source for both experimentation and potential therapeutic uses.
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Affiliation(s)
- Xinchun Liu
- Department of Orthopedics, First Affiliated Hospital, China Medical University, 155 Nan Jing Bei Street, He Ping District, Shenyang 110001, China
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67
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Navarro-Galve B, Martinez-Serrano A. “Is there any need to argue…” about the nature and genetic signature of in vitro neural stem cells? Exp Neurol 2006; 199:20-5. [PMID: 16740262 DOI: 10.1016/j.expneurol.2006.03.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2005] [Accepted: 03/05/2006] [Indexed: 01/23/2023]
Affiliation(s)
- Beatriz Navarro-Galve
- Department of Molecular Biology and Center of Molecular Biology "Severo Ochoa", Laboratory CX-450, Autonomous University of Madrid and Spanish Council for Research [UAM-CSIC], Campus Cantoblanco, 28049-Madrid, Spain
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68
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Wright LS, Prowse KR, Wallace K, Linskens MHK, Svendsen CN. Human progenitor cells isolated from the developing cortex undergo decreased neurogenesis and eventual senescence following expansion in vitro. Exp Cell Res 2006; 312:2107-20. [PMID: 16631163 DOI: 10.1016/j.yexcr.2006.03.012] [Citation(s) in RCA: 115] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2005] [Revised: 03/08/2006] [Accepted: 03/10/2006] [Indexed: 12/11/2022]
Abstract
Isolation of a true self-renewing stem cell from the human brain would be of great interest as a reliable source of neural tissue. Here, we report that human fetal cortical cells grown in epidermal growth factor expressed low levels of telomerase and telomeres in these cultures shortened over time leading to growth arrest after 30 weeks. Following leukemia inhibitory factor (LIF) supplementation, growth rates and telomerase expression increased. This was best demonstrated following cell cycle synchronization and staining for telomerase using immunocytochemistry. This increase in activity resulted in the maintenance of telomeres at approximately 7 kb for more than 60 weeks in vitro. However, all cultures displayed a lack of oligodendrotye production, decreases in neurogenesis over time and underwent replicative senescence associated with increased expression of p21 before 70 weeks in vitro. Thus, under our culture conditions, these cells are not stable, multipotent, telomerase expressing self-renewing stem cells. They may be more accurately described as human neural progenitor cells (hNPC) with limited lifespan and bi-potent potential (neurons/astrocytes). Interestingly, hNPC follow a course of proliferation, neuronal production and growth arrest similar to that seen during expansion and development of the human cortex, thus providing a possible model neural system. Furthermore, due to their high expansion potential and lack of tumorogenicity, these cells remain a unique and safe source of tissue for clinical transplantation.
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Affiliation(s)
- Lynda S Wright
- Waisman Center and Departments of Neurology and Anatomy University of Wisconsin-Madison, WI 53705-2280, USA
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69
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Wilson PG, Stice SS. Development and differentiation of neural rosettes derived from human embryonic stem cells. ACTA ACUST UNITED AC 2006; 2:67-77. [PMID: 17142889 DOI: 10.1007/s12015-006-0011-1] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/1999] [Revised: 11/30/1999] [Accepted: 11/30/1999] [Indexed: 12/17/2022]
Abstract
Neurons and glia are important targets of human embryonic stem cell research, promising a renewable source of these differentiated cells for biomedical research and regenerative medicine. Neurons and glia are derived in vivo from the neuroepithelium of the neural tube. Concomitant to development along the anterior to posterior axis, gradients of morphogens across the dorsal and ventral axis of the neural tube establish positional codes that generate distinct progenitor domains and ultimately specify subtype identity. The neural rosette is the developmental signature of neuroprogenitors in cultures of differentiating embryonic stem cells; rosettes are radial arrangements of columnar cells that express many of the proteins expressed in neuroepithelial cells in the neural tube. In addition to similar morphology, neuroprogenitors within neural rosettes differentiate into the main classes of progeny of neuroepithelial cells in vivo: neurons, oligodendrocytes, and astrocytes. Despite these similarities, important differences exist and the extent to which neural rosettes can model neurogenesis in vivo is not yet clear. Here, the authors review the recent studies on the development and differentiation of neural rosettes from human embryonic stem cells. The authors focus on efforts to generate motor neurons and oligodendrocytes in vitro as representative of the challenges to obtaining the progeny of a single progenitor domain with in vitro methods. Opportunities for further progress are discussed.
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Affiliation(s)
- Patricia G Wilson
- Regenerative Bioscience Center, University of Georgia, Athens, GA. pgwilson@@uga.edu
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70
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Bréjot T, Blanchard S, Hocquemiller M, Haase G, Liu S, Nosjean A, Heard JM, Bohl D. Forced expression of the motor neuron determinant HB9 in neural stem cells affects neurogenesis. Exp Neurol 2006; 198:167-82. [PMID: 16434037 DOI: 10.1016/j.expneurol.2005.11.026] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2005] [Revised: 10/12/2005] [Accepted: 11/22/2005] [Indexed: 11/25/2022]
Abstract
In contrast to mouse embryonic stem cells and in spite of overlapping gene expression profiles, neural stem cells (NSCs) isolated from the embryonic spinal cord do not respond to physiological morphogenetic stimuli provided by Sonic hedgehog and retinoic acid and do not generate motor neurons upon differentiation. Transcription factors expressed in motor neuron progenitors during embryogenesis include Pax6, Ngn2, Nkx6.1 and Olig2, whose expression precedes that of factors specifying motor neuron fate, including HB9, Islet1 and LIM3. We showed that all these factors were present in neural progenitors derived from mouse ES cells, whereas NSCs derived from the rat embryonic spinal cord expressed neither HB9 nor Islet1 and contained low levels of Nkx6.1 and LIM3. We constructed a lentivirus vector to express HB9 and GFP in NSCs and examined the consequences of HB9 expression on other transcription factors and cell differentiation. Compared to cell expressing GFP alone, NSCs expressing GFP and HB9 cycled less rapidly, downregulated Pax6 and Ngn2 mRNA levels, produced higher proportions of neurons in vitro and lower numbers of neurons after transplantation in the spinal cord of recipient rats. Oligodendrocytic and astrocytic differentiations were not affected. HB9 expressing NSCs did not express Islet1 or upregulate LIM3. They neither responded to Sonic hedgehog and retinoic acid nor produced cholinergic neurons. We concluded that forced HB9 expression affected neurogenesis but was not sufficient to confer motor neuron fate to NSCs.
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Affiliation(s)
- Thomas Bréjot
- Unité Rétrovirus et Transfert Génétique, INSERM U622, Département Neuroscience, Institut Pasteur, 28, rue du Dr. Roux, 75015 Paris, France
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71
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Tarasenko YI, Gao J, Nie L, Johnson KM, Grady JJ, Hulsebosch CE, McAdoo DJ, Wu P. Human fetal neural stem cells grafted into contusion-injured rat spinal cords improve behavior. J Neurosci Res 2006; 85:47-57. [PMID: 17075895 DOI: 10.1002/jnr.21098] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Grafted human neural stem cells (hNSCs) may help to alleviate functional deficits resulting from spinal cord injury by bridging gaps, replacing lost neurons or oligodendrocytes, and providing neurotrophic factors. Previously, we showed that primed hNSCs differentiated into cholinergic neurons in an intact spinal cord. In this study, we tested the fate of hNSCs transplanted into a spinal cord T10 contusion injury model. When grafted into injured spinal cords of adult male rats on either the same day or 3 or 9 days after a moderate contusion injury, both primed and unprimed hNSCs survived for 3 months postengraftment only in animals that received grafts at 9 days postinjury. Histological analyses revealed that primed hNSCs tended to survive better and differentiated at higher rates into neurons and oligodendrocytes than did unprimed counterparts. Furthermore, only primed cells gave rise to cholinergic neurons. Animals receiving primed hNSC grafts on the ninth day postcontusion improved trunk stability, as determined by rearing activity measurements 3 months after grafting. This study indicates that human neural stem cell fate determination in vivo is influenced by the predifferentiation stage of stem cells prior to grafting. Furthermore, stem cell-mediated facilitation of functional improvement depends on the timing of transplantation after injury, the grafting sites, and the survival of newly differentiated neurons and oligodendrocytes.
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Affiliation(s)
- Yevgeniya I Tarasenko
- Department of Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, Texas 77555, USA
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Awai M, Koga T, Inomata Y, Oyadomari S, Gotoh T, Mori M, Tanihara H. NMDA-induced retinal injury is mediated by an endoplasmic reticulum stress-related protein, CHOP/GADD153. J Neurochem 2006; 96:43-52. [PMID: 16269013 DOI: 10.1111/j.1471-4159.2005.03502.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
We investigated the role of an endoplasmic reticulum stress-associated protein, CHOP/GADD153, after NMDA-induced mouse retinal damage. After injection of NMDA into the vitreous, TUNEL-positive cells were detected in the retinal ganglion cell layer (GCL) and inner nuclear layer (INL) at 6 h after NMDA injection, and these gradually increased in number up to 24 h. Analysis by real-time RT-PCR revealed that CHOP mRNA was induced by about 3-fold, at 2 h after NMDA injection. Immunoreactivity for the CHOP protein was intense in cells of the GCL following NMDA treatment. Immunoblot analysis showed that NMDA injection increased the expression of CHOP protein in the retina. Compared with wild-type mice, CHOP/ mice were more resistant to NMDA-induced retinal cell death as determined by TUNEL assay. At 7 days after NMDA treatment, the thickness of the inner plexiform layer and INL were larger in CHOP/ mice than in wild-type mice. The number of residual cells in the GCL following NMDA treatment was significantly higher in CHOP/ mice than in wild-type mice. In conclusion, CHOP is induced in mouse retina by NMDA treatment, and CHOP/ mice are more resistant to NMDA-induced retinal damage, suggesting that CHOP plays an important role in NMDA-induced retinal cell death.
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Affiliation(s)
- Maiko Awai
- Department of Ophthalmology and Visual Science, Kumamoto University Graduate School of Medical Sciences, Kumamoto, Japan
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73
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Pallini R, Vitiani LR, Bez A, Casalbore P, Facchiano F, Di Giorgi Gerevini V, Falchetti ML, Fernandez E, Maira G, Peschle C, Parati E. Homologous Transplantation of Neural Stem Cells to the Injured Spinal Cord of Mice. Neurosurgery 2005; 57:1014-25; discussion 1014-25. [PMID: 16284571 DOI: 10.1227/01.neu.0000180058.58372.4c] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVE Murine neural stem cells (NSCs) were homografted onto the injured spinal cord (SC) to assess their potential to improve motor behavior, to differentiate as neurons, and to establish synapse-like contacts with the descending axonal paths of the host. In addition, we investigated whether transduced NSCs over-expressing vascular endothelial growth factor might exert any angiogenetic effect in the injured SC. METHODS NSCs derived from mouse embryos were transduced to express either green fluorescent protein or vascular endothelial growth factor. The cells were engrafted in mice where an extended dorsal funiculotomy had been performed at the T8-T9 level. At intervals from 4 to 12 weeks after grafting, motor behavior was assessed using an open field locomotor scale and footprint analysis. At the same time points, the SC was studied by conventional histology, immunohistochemistry, and fluorescence microscopy. The interactions between the grafted NSCs and descending axonal paths were investigated using anterogradely transported fluorescent axonal tracers. RESULTS By the 12-week time point, mice engrafted with NSCs significantly improved both their locomotor score on open field test and their base of support on footprint analysis. Histological studies showed that green fluorescent protein-positive NSCs survived as long as 12 weeks after grafting, migrated from the grafting site with a tropism toward the lesion, and either remained undifferentiated or differentiated into the astrocytic phenotype without neuronal or oligodendrocytic differentiation. Interestingly, the NSC-derived astrocytes expressed vimentin, suggesting that these cells differentiated as immature astrocytes. The tips of severed descending axonal paths came adjacent to grafted NSCs without forming synapse-like structures. When genetically engineered to over-express vascular endothelial growth factor, the grafted NSCs significantly increased vessel density in the injured area. CONCLUSION In the traumatically injured mice SC, NSC grafting improves motor recovery. Although differentiation of engrafted NSCs is restricted exclusively toward the astrocytic phenotype, the NSC-derived astrocytes show features that are typical of the early phase after SC injury when the glial scar is still permissive to regenerating axons. The immature phenotype of the NSC-derived astrocytes suggests that these cells might support neurite outgrowth by the host neurons. Thus, modifying the glial scar with NSCs might enhance axonal regeneration in the injured area. The use of genetically engineered NSCs that express trophic factors appears to be an attractive tool in SC transplantation research.
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Affiliation(s)
- Roberto Pallini
- Department of Neurosurgery, Laboratory for Neural Stem Cells, Center for Research on Regeneration of the Nervous System, Catholic University School of Medicine, Rome, Italy.
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74
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Akimov SS, Ramezani A, Hawley TS, Hawley RG. Bypass of senescence, immortalization, and transformation of human hematopoietic progenitor cells. Stem Cells 2005; 23:1423-33. [PMID: 16144874 PMCID: PMC1360608 DOI: 10.1634/stemcells.2005-0390] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
We attempted to extend the lifespan of CD34+ stem/progenitor cells in human cord blood (CB) by transduction with lentiviral vectors carrying the human telomerase catalytic subunit (hTERT) and/or the human papillomavirus type 16 (HPV16) E6 and E7 oncogenes. We found that hTERT was incapable of prolonging the replicative capacity of CB cells maintained under serum-free conditions in the presence of stem cell factor, Flt3 ligand, thrombopoietin, and interleukin-3 beyond 4 months (n=3). However, transduced CB cells cultured in the same cytokine cocktail constitutively expressing HPV16 E6/E7 alone (n=2) or in concert with hTERT (n=9) continued to proliferate, giving rise to permanent (>2 years) cell lines with a CD45+ CD34- CD133+/- CD44+ CD235a+ CD71+ CD203+ CD33+ CD13+ myeloerythroid/mast cell progenitor phenotype. Notably, CB cell cultures expressing only HPV16 E6/E7 went through a crisis period, and the resulting oligoclonal cell lines were highly aneuploid. By comparison, the CB cell lines obtained by coexpression of HPV16 E6/E7 plus hTERT exhibited near-diploid karyotypes with minimal chromosomal aberrations, concomitant with stabilization of telomere length, yet were clonally derived. The immortalized E6/E7 plus hTERT-expressing CB cells were not tumorigenic when injected intravenously or subcutaneously into sublethally irradiated immunodeficient nonobese diabetic/severe combined immunodeficient mice but could be converted to a malignant state by ectopic expression of a v-H-ras or BCR-ABL oncogene. These findings provide new insights into the mechanisms governing the senescence checkpoint of primitive human hematopoietic precursors and establish a paradigm for studies of the multistep process of human leukemogenesis.
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Affiliation(s)
- Sergey S. Akimov
- Department of Anatomy and Cell Biology, The George Washington University Medical Center, Washington, DC, USA
| | - Ali Ramezani
- Department of Anatomy and Cell Biology, The George Washington University Medical Center, Washington, DC, USA
| | - Teresa S. Hawley
- Flow Cytometry Core Facility, The George Washington University Medical Center, Washington, DC, USA
| | - Robert G. Hawley
- Department of Anatomy and Cell Biology, The George Washington University Medical Center, Washington, DC, USA
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75
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Singh Roy N, Nakano T, Xuing L, Kang J, Nedergaard M, Goldman SA. Enhancer-specified GFP-based FACS purification of human spinal motor neurons from embryonic stem cells. Exp Neurol 2005; 196:224-34. [PMID: 16198339 DOI: 10.1016/j.expneurol.2005.06.021] [Citation(s) in RCA: 130] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2005] [Revised: 06/09/2005] [Accepted: 06/29/2005] [Indexed: 12/23/2022]
Abstract
Human embryonic stem (hES) cells may generate all major somatic cell types, yet no neuronal subtype has yet been specifically generated in useful purity from hES culture. We report here the selective induction and isolation of functional spinal motor neurons (MNs) from human ES cells. hES cells of the H1 line were transfected with plasmids encoding GFP placed under the control of an MN-specifying enhancer within the 5'-regulatory region of the gene encoding the transcription factor Hb9 and treated with sonic hedgehog (Shh) and retinoic acid (RA). As MNs were induced under the influence of Shh and RA, they activated Hb9-driven GFP expression, permitting their isolation by fluorescence-activated cell sorting (FACS). The MNs thereby generated and isolated became cholinergic and achieved functional maturation in vitro, as evidenced by their fast sodium currents and action potentials on whole-cell patch-clamp and alpha-bungarotoxin-identified clustering of AChR receptors on co-cultured skeletal myoblasts. The serial combination of these two approaches, motor neuron phenotypic induction followed by Hb9 enhancer-based FACS, permitted the high-efficiency induction and isolation of functional motor neurons from hES cells. These results suggest the utility of promoter/enhancer-based FACS for the isolation of specific phenotypes from hES cell populations as a means of purifying clinically appropriate vectors for cell therapy.
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Affiliation(s)
- Neeta Singh Roy
- Department of Neurology, Cornell University Medical College, NYC, NY 10021, USA.
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76
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Abstract
Multipotent neural stem cells, capable of giving rise to both neurons and glia, line the cerebral ventricles of all adult animals, including humans. In addition, distinct populations of nominally glial progenitor cells, which also have the capacity to generate several cell types, are dispersed throughout the subcortical white matter and cortex. A number of approaches have evolved for using neural progenitor cells in cell therapy. Four strategies are especially attractive for clinical translation: first, transplantation of oligodendrocyte progenitor cells as a means of treating the disorders of myelin; second, transplantation of phenotypically restricted neuronal progenitor cells to treat diseases of discrete loss of a single neuronal phenotype, such as Parkinson disease; third, implantation of mixed progenitor pools to treat diseases characterized by the loss of several discrete phenotypes, such as spinal cord injury; and fourth, mobilization of endogenous neural progenitor cells to restore neurons lost as a result of neurodegenerative diseases, in particular Huntington disease. Together, these may present the most compelling strategies and near-term disease targets for cell-based neurological therapy.
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Affiliation(s)
- Steve Goldman
- Division of Cell and Gene Therapy, Department of Neurology, 601 Elmwood Ave., Box 645, University of Rochester Medical Center, Rochester, New York 14642, USA.
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77
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Igura K, Zhang X, Takahashi K, Mitsuru A, Yamaguchi S, Takashi TA. Isolation and characterization of mesenchymal progenitor cells from chorionic villi of human placenta. Cytotherapy 2005; 6:543-53. [PMID: 15770794 DOI: 10.1080/14653240410005366-1] [Citation(s) in RCA: 194] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
BACKGROUND BM-derived mesenchymal stem cells (MSC) are attractive sources for autotransplantation with no risk of rejection, but the use of these cells bas problems, including the necessity of harvesting BM from donors, the donors' age-dependency, limitation to autologous use and difficulty of use for patients with hereditary diseases. We report a method of isolating placenta-derived mesenchymal progenitor cells (PDMPC) that can be used as an alternative source of MSC. METHODS We isolated PDMPC from human fetal chorionic villi using the explant culture method, from placentas collected after neonatal delivery (38-40 weeks of gestation). The PDMPC were characterized by morphologic and immunophenotypic analysis. The differentiation ability of mesenchymal and neural lineages was detected using specific culture conditions and determined by morphology, reverse transcription(RT)-PCR, histochemical staining and immunocytostaining. RESULTS The PDMPC all originated from fetal chorionic villi, as confirmed by fluorescence in situ hybridization analysis. The PDMPC population consisted of spindle-shaped cells and large flat cells. The PDMPCexpressed CD13, CD44, CD73, CD90, CDIO5 and HLA class I as surface epitopes, but not CD31, CD34, CD45 and HLA-DR. These cells differentiated into osteocytes, chondrocytes and adipocytes under specific culture conditions, and were also induced to form neural-like cells. DISCUSSION Our study shows that PDMPC can differentiate into mesenchymal lineages and be induced to form neural-like cells. Thus, PDMPCisolated from chorionic villi of placenta may provide a novel source for the research of stem and progenitor cells in placenta, cell therapy and regenerative medicine, particularly as a source of allogenic mesenchymal stem and progenitor cells with little ethical conflict and various advantages
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Affiliation(s)
- K Igura
- Division of Cell Processing, Institute of Medical Science, The University of Tokyo, Japan
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78
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Püttmann S, Senner V, Braune S, Hillmann B, Exeler R, Rickert CH, Paulus W. Establishment of a benign meningioma cell line by hTERT-mediated immortalization. J Transl Med 2005; 85:1163-71. [PMID: 15965488 DOI: 10.1038/labinvest.3700307] [Citation(s) in RCA: 85] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Meningioma represents the most common intracranial tumor, but well-characterized cell lines derived from benign meningiomas are not available. A major reason for the lack of benign tumor cell lines is senescence of nonmalignant cells in vitro, while malignant cells are often immortal. We have developed a meningioma cell line by retrovirally transducing primary cells derived from a human WHO grade I meningothelial meningioma with the human telomerase reverse transcriptase (hTERT) gene, which enables bypassing cellular senescence. Five clones have been cultured for more than 21 months so far, while corresponding nontransfected cells ceased proliferation within 3 months. Quantitative RT-PCR and a telomeric repeat amplification protocol (TRAP) assay revealed high hTERT mRNA levels and high telomerase activity in all transduced populations, while nontransduced cells were negative. The average telomere size of transduced cells was considerably longer than that of parental cells and the biopsy specimen. One clone, designated Ben-Men-1, was characterized in more detail, and exhibited typical cytological, immunocytochemical, ultrastructural and genetical features of meningioma, including whorl formation, expression of epithelial membrane antigen, desmosomes and interdigitating cell processes, as well as -22q. Following subdural transplantation into nude mice, tumor tissue with typical histological features of meningothelial meningioma was found. We conclude that Ben-Men-1 represents an immortalized yet differentiated cell line useful for biological and therapeutical studies on meningioma.
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Affiliation(s)
- Sylvia Püttmann
- Institute of Neuropathology, University Hospital, Münster, Germany
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79
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Bayne S, Liu JP. Hormones and growth factors regulate telomerase activity in ageing and cancer. Mol Cell Endocrinol 2005; 240:11-22. [PMID: 16005142 DOI: 10.1016/j.mce.2005.05.009] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2005] [Accepted: 05/23/2005] [Indexed: 01/05/2023]
Abstract
Telomerase is a specialised reverse transcriptase that synthesises and preserves telomeres (the ends of chromosomes), thereby playing a key role in regulating the lifespan of cell proliferation. Telomerase activity is critically involved in cell development, ageing and tumourigenesis. Activation of telomerase to maintain telomeres is required for self renewal and proliferative expansion of a number of cell types, including stem cells, activated lymphocytes and cancerous cells. However, recent studies show that the safeguard mechanisms and the modes of regulation of telomerase are more revealing than thought under various physiological and pathological conditions. Considerable evidence suggests that hormones and growth factors are crucially involved in regulating telomerase activity and gene expression of telomerase reverse transcriptase (TERT). This review briefly summarises our current understanding of how hormones and growth factors regulate the telomerase and telomere network and how deregulation can induce ageing and related diseases such as cancer.
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Affiliation(s)
- Sharyn Bayne
- Molecular Signalling Laboratory, Department of Immunology, Monash University, AMREP, Prahran, Melbourne, Vic., Australia
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80
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Schreurs MWJ, Hermsen MAJA, Geltink RIK, Scholten KBJ, Brink AATP, Kueter EWM, Tijssen M, Meijer CJLM, Ylstra B, Meijer GA, Hooijberg E. Genomic stability and functional activity may be lost in telomerase-transduced human CD8+ T lymphocytes. Blood 2005; 106:2663-70. [PMID: 16002425 DOI: 10.1182/blood-2004-09-3742] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
To obtain the large amount of T cells required for adoptive immunotherapy in a clinical setting, T-cell lifespan extension by human telomerase reverse transcriptase (hTERT) transduction is of particular interest. However, constitutive expression of hTERT is associated with malignant transformation and thus warrants a detailed evaluation of the safety of hTERT-transduced T cells before clinical application. In view of this, we performed an extensive cytogenetic analysis of hTERT-transduced MART-1 (melanoma antigen recognized by T cell 1)-and human papillomavirus type 16 (HPV16) E7-specific human CD8+ cytotoxic T lymphocytes (CTLs), reactive against melanoma and cervical carcinoma, respectively. Our results, obtained by (spectral) karyotyping and array comparative genomic hybridization, showed the development of minor chromosomal aberrations in an hTERT-transduced MART-1-specific CTL clone, whereas severe clonal aberrations were detected in an hTERT-transduced HPV16 E7-specific CTL clone. Furthermore, hTERT transduction did not protect CTLs from immunosenescence, because the HPV16 E7-specific, hTERT-transduced CTL clone showed a decreased functional activity on prolonged culture. Although the general frequency of major chromosomal aberrations in hTERT-transduced CTLs and the in vivo significance of our observations remain still unclear at this point, the currently available data suggest that clinical application of hTERT-transduced CTLs should proceed with caution.
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Affiliation(s)
- Marco W J Schreurs
- Department of Pathology, VU University Medical Center, de Boelelaan 1117, 1081 HV Amsterdam, The Netherlands
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81
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Nakano T, Windrem M, Zappavigna V, Goldman SA. Identification of a conserved 125 base-pair Hb9 enhancer that specifies gene expression to spinal motor neurons. Dev Biol 2005; 283:474-85. [PMID: 15913596 DOI: 10.1016/j.ydbio.2005.04.017] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2005] [Revised: 04/08/2005] [Accepted: 04/12/2005] [Indexed: 11/26/2022]
Abstract
The homeobox gene Hb9 is expressed selectively by motor neurons (MNs) in the developing CNS. Previous studies have identified a 9-kb 5' fragment of the mouse Hb9 gene that is sufficient to direct gene expression to spinal MNs in vivo. Here, we sought to identify more discrete MN-specifying elements, using homology searches between genomic sequences of evolutionarily distant species. Based on homology screening of the mouse and human Hb9 promoters, we identified a 3.6-kb Hb9 enhancer that proved sufficient to drive MN-specific lacZ expression. We then compared mouse, human, and pufferfish (Fugu rubripes) genomic sequences, and identified a conserved 438-bp sequence, consisting of noncontiguous 313-bp and 125-bp fragments, residing within the 3.6-kb Hb9 enhancer. The zebrafish (Danio rerio) Hb9 genomic region was then found to have two identical copies of the 125-bp sequence, but no counterpart for the 313-bp sequence. Transgenic analysis showed that the 125-bp alone was both necessary and sufficient to direct spinal MN-specific lacZ expression, whereas the 313-bp sequence had no such enhancer activity. Moreover, the 125-bp Hb9 enhancer was found to harbor two Hox/Pbx consensus-binding sequences, mutations of which completely disrupted thoracolumbar Hb9 expression. These data suggest that Hox/Pbx plays a critical role in the segmental specification of spinal MNs. Together, these results indicate that the molecular pathways regulating Hb9 expression are evolutionarily conserved, and that MN-specific gene expression may be directed and achieved using a small 125-bp 5' enhancer.
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Affiliation(s)
- Takahiro Nakano
- Department of Neurology and Neuroscience, Cornell University Medical Center, New York, NY 10021, USA
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82
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Zhang H, Zhao Y, Zhao C, Yu S, Duan D, Xu Q. Long-term expansion of human neural progenitor cells by epigenetic stimulation in vitro. Neurosci Res 2005; 51:157-65. [PMID: 15681033 DOI: 10.1016/j.neures.2004.10.010] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2004] [Accepted: 10/25/2004] [Indexed: 11/27/2022]
Abstract
Human neural progenitor cells (hNPCs) are currently believed to have important potential for clinical application and basic neuroscience research. In the present study, we have developed a new technique for expansion of human neural progenitor cells in vitro. We showed that the cultures of hNPCs in monolayer could keep the same features with that growing in neurospheres. These cells expressed the typical protein of neural progenitors, nestin, and could form neurons and astrocytes upon differentiation. Using this method, we achieved an exponential increase in cells number over a period of 240 days in vitro. We also confirmed these cells expressed the orphan nuclear receptor-related factor 1 (Nurr1). Furthermore, we acquired the GFP-expressing human neural progenitor cells using retroviral-mediated transgenic system. The results of present study indicate the feasibility of long-term in vitro expansion of human neural progenitor cells using the monolayer culture technique, which may be of value as vehicles for ex vivo gene transfer to the CNS and as a potential source for basic research of dopaminergic (DA) neurons development.
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Affiliation(s)
- Haiyan Zhang
- Beijing Institute for Neuroscience, The Beijing Center of Neural Regeneration and Repairing, Capital University of Medical Sciences, Beijing 100054, China
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83
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Sonntag KC, Simantov R, Isacson O. Stem cells may reshape the prospect of Parkinson's disease therapy. ACTA ACUST UNITED AC 2005; 134:34-51. [PMID: 15790528 DOI: 10.1016/j.molbrainres.2004.09.002] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/09/2004] [Indexed: 12/21/2022]
Abstract
The concept of cell replacement to compensate for cell loss and restore functionality has entered several disease entities including neurodegenerative disorders. Recent clinical studies have shown that transplantation of fetal dopaminergic (DA) cells into the brain of Parkinson's disease (PD) patients can reduce disease-associated motor deficits. However, the use of fetal tissue is associated with practical and ethical problems including low efficiency, variability in the clinical outcome and controversy regarding the use of fetuses as donor. An alternative cell resource could be embryonic stem (ES) cells, which can be cultivated in unlimited amounts and which have the potential to differentiate into mature DA cells. Several differentiation protocols have been developed, and some progress has been made in understanding the mechanisms underlying DA specification in ES cell development, but the "holy grail" in this paradigm, which is the production of sufficient amounts of the "right" therapeutic DA cell, has not yet been accomplished. To achieve this goal, several criteria on the transplanted DA cells need to be fulfilled, mainly addressing cell survival, accurate integration in the brain circuitry, normal function, no tumor formation, and no immunogenicity. Here, we summarize the current state of ES cell-derived DA neurogenesis and discuss the aspects involved in generating an optimal cell source for cell replacement in PD.
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Affiliation(s)
- Kai-Christian Sonntag
- Udall Parkinson's Disease Research Center of Excellence, McLean Hospital/Harvard Medical School, 115 Mill Street, Belmont, MA 02478, USA.
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84
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Ramer LM, Ramer MS, Steeves JD. Setting the stage for functional repair of spinal cord injuries: a cast of thousands. Spinal Cord 2005; 43:134-61. [PMID: 15672094 DOI: 10.1038/sj.sc.3101715] [Citation(s) in RCA: 105] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Here we review mechanisms and molecules that necessitate protection and oppose axonal growth in the injured spinal cord, representing not only a cast of villains but also a company of therapeutic targets, many of which have yet to be fully exploited. We next discuss recent progress in the fields of bridging, overcoming conduction block and rehabilitation after spinal cord injury (SCI), where several treatments in each category have entered the spotlight, and some are being tested clinically. Finally, studies that combine treatments targeting different aspects of SCI are reviewed. Although experiments applying some treatments in combination have been completed, auditions for each part in the much-sought combination therapy are ongoing, and performers must demonstrate robust anatomical regeneration and/or significant return of function in animal models before being considered for a lead role.
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Affiliation(s)
- L M Ramer
- ICORD (International Collaboration on Repair Discoveries), The University of British Columbia, Vancouver, BC, Canada
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85
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86
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Li X, Xu J, Bai Y, Wang X, Dai X, Liu Y, Zhang J, Zou J, Shen L, Li L. Isolation and characterization of neural stem cells from human fetal striatum. Biochem Biophys Res Commun 2005; 326:425-34. [PMID: 15582595 DOI: 10.1016/j.bbrc.2004.11.044] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2004] [Indexed: 11/13/2022]
Abstract
This paper described that neural stem cells (hsNSCs) were isolated and expanded rapidly from human fetal striatum in adherent culture. The population was serum- and growth factor-dependent and expressed neural stem cell markers. They were capable of multi-differentiation into neurons, astrocytes, and oligodendrocytes. When plated in the dopaminergic neuron inducing medium, human striatum neural stem cells could differentiate into tyrosine hydroxylase positive neurons. hsNSCs were morphologically homogeneous and possessed high proliferation ability. The population doubled every 44.28h and until now it has divided for more than 82 generations in vitro. Normal human diploid karyotype was unchanged throughout the in vitro culture period. Together, this study has exploited a method for continuous and rapid expansion of human neural stem cells as pure population, which maintained the capacity to generate almost fifty percent neurons. The availability of such cells may hold great interest for basic and applied neuroscience.
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Affiliation(s)
- Xiaoxia Li
- Department of Cell Biology, Peking University Health Science Center, Peking University Stem Cell Research Center, Beijing 100083, China
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87
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Abstract
The idea of a cell-based regeneration therapy for controlling or curing chronic human diseases is highly attractive. However, realization of this idea in the clinic has been hampered by the safety concerns associated with the transplantation of immortalized cells into human patients. An elegant study done by Roy and colleagues shows that neural progenitor cells immortalized by the ectopic expression of telomerase reverse transcriptase (TERT) can give rise to specific types of functionally competent neurons both in vitro and in vivo. Importantly, the immortalized progenitors maintained their phenotype with no evidence of transformation even several months after transplantation in mouse disease models. Although the potential use of telomerase-immortalized cells in the clinic remains controversial, Roy and colleagues work provides a compelling reason to seriously evaluate the potential use of telomerase-immortalized progenitor cells to treat neurodegenerative and other chronic human illnesses.
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Affiliation(s)
- Sridaran Natesan
- Sanofi-Aventis Cambridge Genomics Center, 26 Landsdowne Street, Cambridge, Massachussetts 02139, USA.
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88
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Wang Y, Bai Y, Li X, Hu Q, Lin C, Xiao Z, Liu Y, Xu J, Shen L, Li L. Fetal human neural progenitors can be the target for tumor transformation. Neuroreport 2004; 15:1907-12. [PMID: 15305135 DOI: 10.1097/00001756-200408260-00015] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The hypothesis that stem cells may seed cancer has emerged from the cancer stem cells concept. However, the experimental systems necessary to provide more direct evidence to support the hypothesis have been lacking. We have used fetal neural progenitor cells (hNPC) transduced with the telomerase hTERT gene to investigate the neoplastic potential of hNPCs. The hTERT-transduced line, hNPCs-G3 lost normal diploid karyotype, showed loss of contact inhibition, anchorage independence, and formed neuroblastoma-like tumours in all of 10 mice. These data suggest that hNPCs have the potential for neoplastic transformation. These data have implications for providing a novel tool to test the feasibility of new anticancer treatment strategies and raise the possibility of a risk for the use of hNPCs in cell transplantation.
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Affiliation(s)
- Yajun Wang
- Stem Cell Research Center, Peking University Health Science Center, Peking University, Beijing, 100083 PR China
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89
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Lindvall O, Kokaia Z, Martinez-Serrano A. Stem cell therapy for human neurodegenerative disorders-how to make it work. Nat Med 2004; 10 Suppl:S42-50. [PMID: 15272269 DOI: 10.1038/nm1064] [Citation(s) in RCA: 664] [Impact Index Per Article: 33.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2004] [Accepted: 03/30/2004] [Indexed: 02/08/2023]
Abstract
Recent progress shows that neurons suitable for transplantation can be generated from stem cells in culture, and that the adult brain produces new neurons from its own stem cells in response to injury. These findings raise hope for the development of stem cell therapies in human neurodegenerative disorders. Before clinical trials are initiated, we need to know much more about how to control stem cell proliferation and differentiation into specific phenotypes, induce their integration into existing neural and synaptic circuits, and optimize functional recovery in animal models closely resembling the human disease.
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Affiliation(s)
- Olle Lindvall
- Laboratory of Neurogenesis and Cell Therapy, Section of Restorative Neurology, Department of Clinical Neuroscience, Wallenberg Neuroscience Center, University Hospital, SE-221 84 Lund, Sweden.
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90
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Abstract
Telomeres, the ends of linear chromosomes, shorten with each round of DNA replication. Loss of telomeric DNA can lead to senescence, a state in which cells no longer divide, and crisis, which triggers cell death. To prevent these phenomena, cancer and stem cells must maintain their telomeres, for example, by expressing telomerase, an enzyme that can extend telomeres. As our knowledge of telomere maintenance increases, opportunities arise for translating telomere biology into clinical medicine. Areas of current investigation include the development of diagnostic and prognostic markers for cancer; the development of chemotherapeutic agents based on telomerase inhibition, an immune response to telomerase, or telomerase-based gene therapy; and engineering rejuvenated tissues by restoring telomerase expression.
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Affiliation(s)
- Gary A Ulaner
- Medical Service, VA Palo Alto Health Care System, CA 94304, USA.
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91
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Roybon L, Christophersen NS, Brundin P, Li JY. Stem cell therapy for Parkinson?s disease: where do we stand? Cell Tissue Res 2004; 318:261-73. [PMID: 15309619 DOI: 10.1007/s00441-004-0946-y] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2004] [Accepted: 06/25/2004] [Indexed: 11/30/2022]
Abstract
A major neuropathological feature of Parkinson's disease (PD) is the loss of nigrostriatal dopaminergic neuron. Patients exhibit motor symptoms, including bradykinesia, rigidity, and tremor. Neural grafting has been reported to restore striatial dopaminergic neurotransmission and induce symptomatic relief. The major limitation of cell replacement therapy for PD is the shortage of suitable donor tissue. The present review describes the possible sources of cells, including embryonic stem cells and somatic adult stem cells, both of which potentially could be used in cell therapy for PD, and discusses the advantages and disadvantages of each cell type.
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Affiliation(s)
- Laurent Roybon
- Section for Neuronal Survival, Wallenberg Neuroscience Center, Lund University, BMC A10, 22184 Lund, Sweden.
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92
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Wang X, Arcuino G, Takano T, Lin J, Peng WG, Wan P, Li P, Xu Q, Liu QS, Goldman SA, Nedergaard M. P2X7 receptor inhibition improves recovery after spinal cord injury. Nat Med 2004; 10:821-7. [PMID: 15258577 DOI: 10.1038/nm1082] [Citation(s) in RCA: 397] [Impact Index Per Article: 19.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2004] [Accepted: 06/25/2004] [Indexed: 01/29/2023]
Abstract
Secondary injury exacerbates the extent of spinal cord insults, yet the mechanistic basis of this phenomenon has largely been unexplored. Here we report that broad regions of the peritraumatic zone are characterized by a sustained process of pathologic, high ATP release. Spinal cord neurons expressed P2X7 purine receptors (P2X7R), and exposure to ATP led to high-frequency spiking, irreversible increases in cytosolic calcium and cell death. To assess the potential effect of P2X7R blockade in ameliorating acute spinal cord injury (SCI), we delivered P2X7R antagonists OxATP or PPADS to rats after acute impact injury. We found that both OxATP and PPADS significantly improved functional recovery and diminished cell death in the peritraumatic zone. These observations demonstrate that SCI is associated with prolonged purinergic receptor activation, which results in excitotoxicity-based neuronal degeneration. P2X7R antagonists inhibit this process, reducing both the histological extent and functional sequelae of acute SCI.
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Affiliation(s)
- Xiaohai Wang
- Department of Neurosurgery, Center for Aging and Developmental Biology, University of Rochester Medical Center, Rochester, New York 14642, USA
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93
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Rothstein J, Snyder E. Response to Stem cell differentiation. Nat Biotechnol 2004. [DOI: 10.1038/nbt0704-805] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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94
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