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Clive N. Svendsen

Bio: Clive N. Svendsen is an academic researcher from Cedars-Sinai Medical Center. The author has contributed to research in topics: Neural stem cell & Stem cell. The author has an hindex of 78, co-authored 283 publications receiving 21604 citations. Previous affiliations of Clive N. Svendsen include University of Wisconsin-Madison & University of California, Los Angeles.


Papers
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Journal ArticleDOI
15 Jan 2009-Nature
TL;DR: This is the first study to show that human induced pluripotent stem cells can be used to model the specific pathology seen in a genetically inherited disease and represents a promising resource to study disease mechanisms, screen new drug compounds and develop new therapies.
Abstract: Spinal muscular atrophy is one of the most common inherited forms of neurological disease leading to infant mortality. Patients have selective loss of lower motor neurons resulting in muscle weakness, paralysis and often death. Although patient fibroblasts have been used extensively to study spinal muscular atrophy, motor neurons have a unique anatomy and physiology which may underlie their vulnerability to the disease process. Here we report the generation of induced pluripotent stem cells from skin fibroblast samples taken from a child with spinal muscular atrophy. These cells expanded robustly in culture, maintained the disease genotype and generated motor neurons that showed selective deficits compared to those derived from the child’s unaffected mother. This is the first study to show that human induced pluripotent stem cells can be used to model the specific pathology seen in a genetically inherited disease. As such, it represents a promising resource to study disease mechanisms, screen new drug compounds and develop new therapies. The inherited disease spinal muscular atrophy (SMA), one of the most common neurological disorders causing death in childhood, is caused by mutations in both copies of the SMN1 gene. Little is known about SMA pathogenesis, partly because it is unique to humans who have two versions of this gene — SMN1 and SMN2; rodents and other lab model candidates have just one. Now a new technique has been developed that creates a tool for studying SMA disease pathology at the cellular level. Skin fibroblasts from a child with SMA (and for comparison from his unaffected mother) were used to generate induced pluripotent stem (iPS) cell lines. They form neural progenitor cultures that can produce differentiated neural tissue and motor neurons that maintain the disease phenotype. The cultures also responded to drugs known to elevate the mutated protein associated with the disease. Similar iPS technology may be of value in the study of other genetic disorders such as Huntington's disease. This paper generates an iPS cell line from patients with spinal muscular atrophy, an autosomal recessive genetic disorder that is one of the most common inherited forms of neurological disease in children.

1,495 citations

Journal ArticleDOI
TL;DR: Positron emission tomography scans of [18F]dopamine uptake showed a significant 28% increase in putamen dopamine storage after 18 months, suggesting a direct effect of GDNF on dopamine function, and warrants careful examination ofGDNF as a treatment for Parkinson disease.
Abstract: Glial cell line-derived neurotrophic factor (GDNF) is a potent neurotrophic factor with restorative effects in a wide variety of rodent and primate models of Parkinson disease, but penetration into brain tissue from either the blood or the cerebro-spinal fluid is limited. Here we delivered GDNF directly into the putamen of five Parkinson patients in a phase 1 safety trial. One catheter needed to be repositioned and there were changes in the magnetic resonance images that disappeared after lowering the concentration of GDNF. After one year, there were no serious clinical side effects, a 39% improvement in the off-medication motor sub-score of the Unified Parkinson's Disease Rating Scale (UPDRS) and a 61% improvement in the activities of daily living sub-score. Medication-induced dyskinesias were reduced by 64% and were not observed off medication during chronic GDNF delivery. Positron emission tomography (PET) scans of [(18)F]dopamine uptake showed a significant 28% increase in putamen dopamine storage after 18 months, suggesting a direct effect of GDNF on dopamine function. This study warrants careful examination of GDNF as a treatment for Parkinson disease.

1,342 citations

Journal ArticleDOI
01 Jun 1999-Neuron
TL;DR: These findings show that genetic targeting can be used to ablate scar-forming astrocytes and demonstrate roles for astroCytes in regulating leukocyte trafficking, repairing the BBB, protecting neurons, and restricting nerve fiber growth after injury in the adult central nervous system.

1,051 citations

Journal ArticleDOI
TL;DR: Findings support the idea that the buildup of “toxic” RNA containing the GGGGCC repeat contributes to the death of motor neurons in ALS, and suggest that antisense oligonucleotides targeting this transcript may be a strategy for treating ALS patients with the C9ORF72 repeat expansion.
Abstract: Amyotrophic lateral sclerosis (ALS) is a severe neurodegenerative condition characterized by loss of motor neurons in the brain andspinalcord.Expansionsofahexanucleotide repeat(GGGGCC) in thenoncodingregionoftheC9ORF72geneare the most common cause of the familial form of ALS (C9-ALS), as well as frontotemporal lobar degeneration and other neurological diseases. How the repeat expansion causes disease remains unclear, with both loss of function (haploinsufficiency) and gain of function (either toxic RNA or protein products) proposed. We report a cellular model of C9-ALS with motor neurons differentiated from induced pluripotent stem cells (iPSCs) derived from ALS patients carrying the C9ORF72 repeat expansion. No significant loss of C9ORF72 expression was observed, and knockdown of the transcript was not toxic to cultured human motor neurons. Transcription of the repeat was increased, leading to accumulation of GGGGCC repeat–containing RNA foci selectively in C9-ALS iPSC-derived motor neurons. Repeat-containing RNA foci colocalized with hnRNPA1 andPur-a, suggestingthat they maybe ableto alter RNAmetabolism. C9-ALSmotor neurons showed altered expression of genes involved in membrane excitability including DPP6, and demonstrated a diminished capacity to fire continuous spikes upon depolarization compared to control motor neurons. Antisense oligonucleotides targeting the C9ORF72 transcript suppressed RNA foci formation and reversed gene expression alterations in C9-ALS motorneurons.Thesedatashowthatpatient-derivedmotorneuronscanbeusedtodelineatepathogeniceventsinALS.

611 citations

Journal ArticleDOI
TL;DR: This simple and novel culture method allows the rapid expansion of large numbers of non-transformed human neural precursor cells which may be of use in drug discovery, ex vivo gene therapy and clinical neural transplantation.

595 citations


Cited by
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Journal ArticleDOI
11 Sep 2003-Neuron
TL;DR: PD models based on the manipulation of PD genes should prove valuable in elucidating important aspects of the disease, such as selective vulnerability of substantia nigra dopaminergic neurons to the degenerative process.

4,872 citations

Journal ArticleDOI
26 Jan 2017-Nature
TL;DR: It is shown that activated microglia induce A1 astrocytes by secreting Il-1α, TNF and C1q, and that these cytokines together are necessary and sufficient to induce A2 astroCytes, which are abundant in various human neurodegenerative diseases.
Abstract: This work was supported by grants from the National Institutes of Health (R01 AG048814, B.A.B.; RO1 DA15043, B.A.B.; P50 NS38377, V.L.D. and T.M.D.) Christopher and Dana Reeve Foundation (B.A.B.), the Novartis Institute for Biomedical Research (B.A.B.), Dr. Miriam and Sheldon G. Adelson Medical Research Foundation (B.A.B.), the JPB Foundation (B.A.B., T.M.D.), the Cure Alzheimer’s Fund (B.A.B.), the Glenn Foundation (B.A.B.), the Esther B O’Keeffe Charitable Foundation (B.A.B.), the Maryland Stem Cell Research Fund (2013-MSCRFII-0105-00, V.L.D.; 2012-MSCRFII-0268-00, T.M.D.; 2013-MSCRFII-0105-00, T.M.D.; 2014-MSCRFF-0665, M.K.). S.A.L. was supported by a postdoctoral fellowship from the Australian National Health and Medical Research Council (GNT1052961), and the Glenn Foundation Glenn Award. L.E.C. was funded by a Merck Research Laboratories postdoctoral fellowship (administered by the Life Science Research Foundation). W.-S.C. was supported by a career transition grant from NEI (K99EY024690). C.J.B. was supported by a postdoctoral fellowship from Damon Runyon Cancer Research Foundation (DRG-2125-12). L.S. was supported by a postdoctoral fellowship from the German Research Foundation (DFG, SCHI 1330/1-1).

4,326 citations

Journal ArticleDOI
TL;DR: Astrocyte functions in healthy CNS, mechanisms and functions of reactive astrogliosis and glial scar formation, and ways in which reactive astrocytes may cause or contribute to specific CNS disorders and lesions are reviewed.
Abstract: Astrocytes are specialized glial cells that outnumber neurons by over fivefold. They contiguously tile the entire central nervous system (CNS) and exert many essential complex functions in the healthy CNS. Astrocytes respond to all forms of CNS insults through a process referred to as reactive astrogliosis, which has become a pathological hallmark of CNS structural lesions. Substantial progress has been made recently in determining functions and mechanisms of reactive astrogliosis and in identifying roles of astrocytes in CNS disorders and pathologies. A vast molecular arsenal at the disposal of reactive astrocytes is being defined. Transgenic mouse models are dissecting specific aspects of reactive astrocytosis and glial scar formation in vivo. Astrocyte involvement in specific clinicopathological entities is being defined. It is now clear that reactive astrogliosis is not a simple all-or-none phenomenon but is a finely gradated continuum of changes that occur in context-dependent manners regulated by specific signaling events. These changes range from reversible alterations in gene expression and cell hypertrophy with preservation of cellular domains and tissue structure, to long-lasting scar formation with rearrangement of tissue structure. Increasing evidence points towards the potential of reactive astrogliosis to play either primary or contributing roles in CNS disorders via loss of normal astrocyte functions or gain of abnormal effects. This article reviews (1) astrocyte functions in healthy CNS, (2) mechanisms and functions of reactive astrogliosis and glial scar formation, and (3) ways in which reactive astrocytes may cause or contribute to specific CNS disorders and lesions.

4,075 citations

Journal ArticleDOI
19 Mar 2010-Cell
TL;DR: There is evidence for a remarkable convergence in the mechanisms responsible for the sensing, transduction, and amplification of inflammatory processes that result in the production of neurotoxic mediators in neurodegenerative diseases.

2,838 citations