Publications by authors named "Stephen L Minger"

29 Publications

  • Page 1 of 1

Stage-specific changes in neurogenic and glial markers in Alzheimer's disease.

Biol Psychiatry 2015 Apr 9;77(8):711-9. Epub 2014 Jun 9.

Wolfson Centre for Age-Related Diseases, King's College London, London, United Kingdom.

Background: Reports of altered endogenous neurogenesis in people with Alzheimer's disease (AD) and transgenic AD models have suggested that endogenous neurogenesis may be an important treatment target, but there is considerable discrepancy among studies. We examined endogenous neurogenesis and glia changes across the range of pathologic severity of AD in people with and without dementia to address this key question.

Methods: Endogenous neurogenesis and glia in the subventricular zone and dentate gyrus neurogenic niches were evaluated using single and double immunohistochemistry and a validated antibody selection for stage-specific and type-specific markers in autopsy tissue from a representative cohort of 28 participants in the Medical Research Council Cognitive Function and Ageing Study. Immunopositive cells were measured blinded to diagnosis using bright-field and fluorescent microscopy.

Results: The number of newly generated neurons significantly declined only in the dentate gyrus of patients with severe tau pathology. No other changes in other neurogenic markers were observed in either of the neurogenic niches. Alterations in astrocytes and microglia were also observed in the dentate gyrus across the different stages of tau pathology. No change in any of the markers was observed in individuals who died with dementia compared with individuals who did not die with dementia.

Conclusions: Alterations in endogenous neurogenesis appeared to be confined to a reduction in the generation of new neurons in the dentate gyrus of patients with AD and severe neurofibrillary tangle pathology and were accompanied by changes in the glia load. These data suggest that intervention enhancing endogenous neurogenesis may be a potential therapeutic target in AD.
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http://dx.doi.org/10.1016/j.biopsych.2014.05.021DOI Listing
April 2015

Developing technologies to unlock the therapeutic and research potential of human stem cells.

Authors:
Stephen L Minger

N Biotechnol 2013 May 5;30(4):378-80. Epub 2012 Dec 5.

GE Healthcare Life Sciences, Maynard Centre, Forest Farm, Whitchurch, Cardiff, CF14 7YT, Wales, United Kingdom.

Since human embryonic stem cells (hESCs) were first isolated and cultured nearly 15 years ago, stem cell biology has been a promising and fast-moving area of research. Improved clinical predictivity in drug development, use in assays to personalise medicine effectively and as the foundation for cell-based therapies are all areas where stem cells can play an important role. But with opportunities come challenges and it is vital that the field of stem cells continues to progress to achieve its potential. This article outlines the measures the Cell Technologies group at GE Healthcare Life Sciences are taking, along with its collaborators in academia, industry and the clinic, to advance stem cell tools and technologies, as well as identifying some future challenges for stem cell research, drug discovery, cell therapy and regenerative medicine.
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http://dx.doi.org/10.1016/j.nbt.2012.11.006DOI Listing
May 2013

Screening ethnically diverse human embryonic stem cells identifies a chromosome 20 minimal amplicon conferring growth advantage.

Authors:
Katherine Amps Peter W Andrews George Anyfantis Lyle Armstrong Stuart Avery Hossein Baharvand Julie Baker Duncan Baker Maria B Munoz Stephen Beil Nissim Benvenisty Dalit Ben-Yosef Juan-Carlos Biancotti Alexis Bosman Romulo Martin Brena Daniel Brison Gunilla Caisander María V Camarasa Jieming Chen Eric Chiao Young Min Choi Andre B H Choo Daniel Collins Alan Colman Jeremy M Crook George Q Daley Anne Dalton Paul A De Sousa Chris Denning Janet Downie Petr Dvorak Karen D Montgomery Anis Feki Angela Ford Victoria Fox Ana M Fraga Tzvia Frumkin Lin Ge Paul J Gokhale Tamar Golan-Lev Hamid Gourabi Michal Gropp Guangxiu Lu Ales Hampl Katie Harron Lyn Healy Wishva Herath Frida Holm Outi Hovatta Johan Hyllner Maneesha S Inamdar Astrid Kresentia Irwanto Tetsuya Ishii Marisa Jaconi Ying Jin Susan Kimber Sergey Kiselev Barbara B Knowles Oded Kopper Valeri Kukharenko Anver Kuliev Maria A Lagarkova Peter W Laird Majlinda Lako Andrew L Laslett Neta Lavon Dong Ryul Lee Jeoung Eun Lee Chunliang Li Linda S Lim Tenneille E Ludwig Yu Ma Edna Maltby Ileana Mateizel Yoav Mayshar Maria Mileikovsky Stephen L Minger Takamichi Miyazaki Shin Yong Moon Harry Moore Christine Mummery Andras Nagy Norio Nakatsuji Kavita Narwani Steve K W Oh Sun Kyung Oh Cia Olson Timo Otonkoski Fei Pan In-Hyun Park Steve Pells Martin F Pera Lygia V Pereira Ouyang Qi Grace Selva Raj Benjamin Reubinoff Alan Robins Paul Robson Janet Rossant Ghasem H Salekdeh Thomas C Schulz Karen Sermon Jameelah Sheik Mohamed Hui Shen Eric Sherrer Kuldip Sidhu Shirani Sivarajah Heli Skottman Claudia Spits Glyn N Stacey Raimund Strehl Nick Strelchenko Hirofumi Suemori Bowen Sun Riitta Suuronen Kazutoshi Takahashi Timo Tuuri Parvathy Venu Yuri Verlinsky Dorien Ward-van Oostwaard Daniel J Weisenberger Yue Wu Shinya Yamanaka Lorraine Young Qi Zhou

Nat Biotechnol 2011 Nov 27;29(12):1132-44. Epub 2011 Nov 27.

Centre for Stem Cell Biology, Department of Biomedical Science, The University of Sheffield, Sheffield, UK.

The International Stem Cell Initiative analyzed 125 human embryonic stem (ES) cell lines and 11 induced pluripotent stem (iPS) cell lines, from 38 laboratories worldwide, for genetic changes occurring during culture. Most lines were analyzed at an early and late passage. Single-nucleotide polymorphism (SNP) analysis revealed that they included representatives of most major ethnic groups. Most lines remained karyotypically normal, but there was a progressive tendency to acquire changes on prolonged culture, commonly affecting chromosomes 1, 12, 17 and 20. DNA methylation patterns changed haphazardly with no link to time in culture. Structural variants, determined from the SNP arrays, also appeared sporadically. No common variants related to culture were observed on chromosomes 1, 12 and 17, but a minimal amplicon in chromosome 20q11.21, including three genes expressed in human ES cells, ID1, BCL2L1 and HM13, occurred in >20% of the lines. Of these genes, BCL2L1 is a strong candidate for driving culture adaptation of ES cells.
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http://dx.doi.org/10.1038/nbt.2051DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3454460PMC
November 2011

The effects of culture on genomic imprinting profiles in human embryonic and fetal mesenchymal stem cells.

Epigenetics 2011 Jan 1;6(1):52-62. Epub 2011 Jan 1.

Institute of Reproductive and Developmental Biology, Imperial Colleg, London, UK.

Human embryonic stem (hES) cells and fetal mesenchymal stem cells (fMSC) offer great potential for regenerative therapy strategies. It is therefore important to characterise the properties of these cells in vitro. One major way the environment impacts on cellular physiology is through changes to epigenetic mechanisms. Genes subject to epigenetic regulation via genomic imprinting have been characterised extensively. The integrity of imprinted gene expression therefore provides a measurable index for epigenetic stability. Allelic expression of 26 imprinted genes and DNA methylation at associated differentially methylated regions (DMRs) was measured in fMSC and hES cell lines. Both cell types exhibited monoallelic expression of 13 imprinted genes, biallelic expression of six imprinted genes, and there were seven genes that differed in allelic expression between cell lines. fMSCs exhibited the differential DNA methylation patterns associated with imprinted expression. This was unexpected given that gene expression of several imprinted genes was biallelic. However, in hES cells, differential methylation was perturbed. These atypical methylation patterns did not correlate with allelic expression. Our results suggest that regardless of stem cell origin, in vitro culture affects the integrity of imprinted gene expression in human cells. We identify biallelic and variably expressed genes that may inform on overall epigenetic stability. As differential methylation did not correlate with imprinted expression changes we propose that other epigenetic effectors are adversely influenced by the in vitro environment. Since DMR integrity was maintained in fMSC but not hES cells, we postulate that specific hES cell derivation and culturing practices result in changes in methylation at DMRs.
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http://dx.doi.org/10.4161/epi.6.1.13361DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3052914PMC
January 2011

Increased neural progenitors in vascular dementia.

Neurobiol Aging 2011 Dec 5;32(12):2152-61. Epub 2010 Feb 5.

Stem Cell Biology Laboratory, Wolfson Centre for Age-Related Diseases, King's College London, London SE1 IUL, UK.

Since groundbreaking studies demonstrated the presence of progenitor cells in the adult human brain, there have been intense interests in their potential therapeutic application, but to date only limited data has been obtained in man. An immunohistological study was performed in order to examine neurogenesis in both the subventricular and peri-infarct zones of vascular dementia patients compared to age-matched controls. The results were striking, showing a significant increase of progenitor cells in both the subventricular zone and in peri-infarct area in patients with vascular dementia compared to controls, which was sustained even in patients with infarcts occurring more than three months prior to autopsy. Moreover, the peri-infarct response appeared to be unified with that of the subventricular zone via a stream of cells, with some of them differentiating into immature neurons. We conclude that neurogenesis is stimulated in vascular dementia patients and, specifically, in patients with visible infarcts. Progenitors may migrate from the neurogenic niche to areas of infarction and differentiate into neurons, even three months after cerebrovascular damage, thus implicating the feasibility of enhancing neurogenesis as a novel treatment approach.
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http://dx.doi.org/10.1016/j.neurobiolaging.2010.01.007DOI Listing
December 2011

Neural progenitors promote axon growth in vitro and ex vivo but not following injury.

J Stem Cells 2009 ;4(1):1-16

Brain Repair Centre, University of Cambridge, Forvie Site, Cambridge, CB2 2PY.

Following an injury to the dorsal roots primary sensory afferents fail to regenerate past the hostile dorsal root entry zone (DREZ), the interface between the peripheral and central nervous system. Neural progenitor cells have previously been utilised as a cellular replacement therapy in a variety of CNS injury models. Here we show for the first time that NPCs are capable of promoting neurite outgrowth from adult sensory neurons in vitro and ex vivo cryo-cultures. The effectiveness of NPCs as a potential means of promoting regeneration of primary afferents across the DREZ was assessed following rhizotomy at the cervical level in the adult rat. Adult rats were subjected to rhizotomy of the dorsal roots between C(5)-T(1) which were then reanastamosed. In conjunction with the rhizotomy NPCs were delivered at the DREZ. NPCs survived transplantation and were observed to differentiate predominantly into glia. Regeneration of the dorsal root fibers was assessed with immunhistochemical analysis of the large and small diameter peptidergic and non-peptidergic afferents. Although afferents appeared near to the DREZ there was little regeneration beyond the DREZ. Furthermore, no significant improvement was observed in behavioural tasks.
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http://dx.doi.org/jsc.2009.4.1.1DOI Listing
April 2016

Sequential RARbeta and alpha signalling in vivo can induce adult forebrain neural progenitor cells to differentiate into neurons through Shh and FGF signalling pathways.

Dev Biol 2009 Feb 7;326(2):305-13. Epub 2008 Dec 7.

The Wolfson Centre For Age-Related Diseases, King's College London, Guy's Campus, London, UK.

We show here the role of retinoic acid receptor (RAR) beta and alpha signalling in proliferation and differentiation of endogenous adult forebrain neural progenitor cells (NPCs). RARbeta activation stimulates Sonic hedgehog signalling (Shh), and induces the proliferation of the NPCs. They can be induced to become Doublecortin (DCX) expressing migrating neuroblasts by RARalpha signalling, some of which differentiate into cholinergic neurons. The same signalling pathways cause the proliferation of embryonic forebrain NPCs. These cells express glial fibrillary acidic protein (GFAP) and are predominantly uni/bipolar, two characteristics of neuronal progenitor cells. We further show that fibroblast growth factor (FGF) signalling, induces the expression of the retinoic acid degrading enzyme cytochrome P450 (cyp) 26a1, and that one of its products, 4-oxo-RA, mimics the action of the RARalpha agonist in the differentiation of the NPCs into cholinergic neurons.
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http://dx.doi.org/10.1016/j.ydbio.2008.11.018DOI Listing
February 2009

Generation of hepatocytes from human embryonic stem cells.

Methods Mol Biol 2009 ;481:169-80

Stem Cell Biology Laboratory, Wolfson Centre for Age-Related Diseases Kings College London, London, UK.

Use of human hepatocytes for therapeutic and drug discovery applications is hampered by limited tissue source and the inability of hepatocytes to proliferate and maintain function long-term in vitro. Human embryonic stem (hES) cells are immortal and pluripotent and may provide a cell source for functional human hepatocytes (1) Here we have outlined some of the protocols currently in use for the generation of hepatocytes from hES cells.
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http://dx.doi.org/10.1007/978-1-59745-201-4_14DOI Listing
March 2009

Isolation, in vitro cultivation and characterisation of foetal liver cells.

Methods Mol Biol 2009 ;481:181-92

Stem Cell Biology Laboratory, Wolfson Centre for Age-Related Diseases King's College London, London, UK.

Hepatocyte transplantation has recently become an efficient clinical method in the treatment of patients with metabolic liver diseases. The shortage of donor cells remains an obstacle to treat more patients. Foetal liver tissues may therefore be useful as an alternative source of generating functional hepatocytes after in vitro culture and maturation.
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http://dx.doi.org/10.1007/978-1-59745-201-4_15DOI Listing
March 2009

Homogeneous monocytes and macrophages from human embryonic stem cells following coculture-free differentiation in M-CSF and IL-3.

Exp Hematol 2008 Sep 11;36(9):1167-75. Epub 2008 Jun 11.

Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford, UK.

Objective: To develop a simple and efficient method for producing homogeneous populations of monocytes and macrophages from human embryonic stem cells (hES).

Materials And Methods: Human embryonic stem cell lines KCL001, KCL002, and HUES-2 were differentiated into monocytes by coculture-free differentiation with two growth factors using a three-step method. The method involved embryoid body (EB) formation in hES media, directed differentiation with macrophage colony-stimulating factor and interleukin (IL)-3, and harvest of nonadherent monocytes from the culture supernatants. hES monocytes (esMCs) were analyzed by microscopy, flow cytometry, transcriptome analysis, and tested for the ability to differentiate into macrophages. hES monocyte-derived macrophages (esMDM) were analyzed for phagocytosis and endocytosis by microscopy and flow cytometry, cytokine secretion by multiplex cytokine assay, and for interferon (IFN)-gamma and IL-4 activation by flow cytometry.

Results: Homogeneous esMCs (>90% CD14-positive) that did not require any additional purification steps were produced after 18.7 +/- 7.7 days (mean +/- SD, n = 19). Production continued for several months when growth factors were replaced, with a total yield of 3.4 x 10(5) +/- 2.0 esMCs (mean +/- SD, n = 9) per EB. Transcriptome analysis of the esMC and the esMDM revealed a distinct myeloid signature that correlated with primary adult blood-derived monocytes and spleen tissue samples but not with other tissue samples tested. We found that esMCs and esMDMs expressed well-defined markers of the mononuclear phagocyte system including PU-1, C/EBPalpha, EMR1, and EMR2, MPEG1, CD1c, CD4, CD18, CD32, CD33, CD68, cathepsins and serine carboxypeptidase. Finally, esMCs differentiated into functional macrophages that could endocytose acetylated low-density lipoprotein, phagocytose opsonized yeast particles, secrete specific cytokines in response to lipopolysaccharide, and be activated differentially with IFN-gamma and IL-4.

Conclusions: We have developed a simple and efficient method for producing homogeneous populations of monocytes and macrophages from hES cells. esMCs have a myeloid signature and can differentiate into functional macrophages. The method should prove useful in answering experimental questions regarding monocyte and macrophage development and biology.
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http://dx.doi.org/10.1016/j.exphem.2008.04.009DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2635571PMC
September 2008

Law should recognize value of interspecies embryos.

Nature 2008 Feb;451(7179):627

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http://dx.doi.org/10.1038/451627aDOI Listing
February 2008

Transplanted neural progenitor cells survive and differentiate but achieve limited functional recovery in the lesioned adult rat spinal cord.

Regen Med 2007 Nov;2(6):929-45

University of Cambridge, Centre for Brain Repair, Forvie Site, Robinson Way, Cambridge, CB2 2PY, UK.

Unlabelled: Endogenous repair after injury in the adult CNS is limited by a number of factors including cellular loss, inflammation, cavitation and glial scarring. Spinal cord neural progenitor cells (SCNPCs) may provide a valuable cellular source for promoting repair following spinal cord injury. SCNPCs are multipotent, can be expanded in vitro, have the capacity to differentiate into CNS cell lineages and are capable of long-term survival following transplantation.

Aims & Method: To determine the extent to which SCNPCs may contribute to spinal cord repair SCNPCs isolated from rat fetal spinal cord were expanded ex vivo and transplanted into the adult rat spinal cord after a dorsal column crush lesion.

Results: The survival and distribution of transplanted cells were examined at 24 h, 1, 2 and 6 weeks after injury. Transplanted cells were identified at all time points, located mainly at the lesion perimeter, indicating good post-transplant cell survival. Furthermore, SCNPCs maintained their ability to differentiate in vivo, with approximately 40% differentiating into cells with a glial morphology, whilst 8% displayed a neural morphology. Transplanted animals were also assessed on a number of behavioral tasks measuring sensorimotor and proprioceptive function to determine the extent to which SCNPC transplants might attenuate lesion-induced functional deficits. SCNPCs failed to promote significant functional recovery, with a small improvement observed in only one of the four tasks employed, primarily related to improvements in sensory function. Tracing of the corticospinal tract and ascending dorsal column pathway revealed no regeneration of the axons beyond the lesion site.

Conclusions: These data indicate that, although transplanted SCNPCs show good survival in the spinal cord injury environment, combination with other treatment strategies is likely to be required for these cells to fully exert their therapeutic potential.
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http://dx.doi.org/10.2217/17460751.2.6.929DOI Listing
November 2007

Embryonic stem cells: protecting pluripotency from alloreactivity.

Curr Opin Immunol 2007 Oct 20;19(5):596-602. Epub 2007 Aug 20.

University of Oxford, Sir William Dunn School of Pathology, South Parks Road, Oxford OX1 3RE, UK.

There can be little doubt that 2006 turned out to be the annus horribilis for therapeutic cloning by somatic nuclear transfer (SNT). As the full extent of the fraud surrounding the generation of patient-specific embryonic stem (ES) cell lines became apparent, hopes began to fade for the advent of cell replacement therapies (CRT), free from the confounding issues of immune rejection. While the dust begins to settle, it is perhaps pertinent to ask whether the promise of SNT is still worth pursuing or whether alternative strategies for immune evasion might help fill the void.
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http://dx.doi.org/10.1016/j.coi.2007.07.010DOI Listing
October 2007

Characterization of human embryonic stem cell lines by the International Stem Cell Initiative.

Nat Biotechnol 2007 Jul 17;25(7):803-16. Epub 2007 Jun 17.

UK Stem Cell Bank, Division of Cell Biology and Imaging, National Institute for Biological Standards and Control, South Mimms, Herts., EN6 3QG, UK.

The International Stem Cell Initiative characterized 59 human embryonic stem cell lines from 17 laboratories worldwide. Despite diverse genotypes and different techniques used for derivation and maintenance, all lines exhibited similar expression patterns for several markers of human embryonic stem cells. They expressed the glycolipid antigens SSEA3 and SSEA4, the keratan sulfate antigens TRA-1-60, TRA-1-81, GCTM2 and GCT343, and the protein antigens CD9, Thy1 (also known as CD90), tissue-nonspecific alkaline phosphatase and class 1 HLA, as well as the strongly developmentally regulated genes NANOG, POU5F1 (formerly known as OCT4), TDGF1, DNMT3B, GABRB3 and GDF3. Nevertheless, the lines were not identical: differences in expression of several lineage markers were evident, and several imprinted genes showed generally similar allele-specific expression patterns, but some gene-dependent variation was observed. Also, some female lines expressed readily detectable levels of XIST whereas others did not. No significant contamination of the lines with mycoplasma, bacteria or cytopathic viruses was detected.
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http://dx.doi.org/10.1038/nbt1318DOI Listing
July 2007

Endogenous neurogenesis in the human brain following cerebral infarction.

Regen Med 2007 Jan;2(1):69-74

Stem Cell Biology Laboratory, Wolfson Centre for Age-Related Diseases, King's College London, London, UK.

Increased endogenous neurogenesis has a significant regenerative role in many experimental models of cerebrovascular diseases, but there have been very few studies in humans. We therefore examined whether there was evidence of altered endogenous neurogenesis in an 84-year-old patient who suffered a cerebrovascular accident 1 week prior to death. Using antibodies that specifically label neural stem/neural progenitor cells, we examined the presence of immunopositive cells around and distant from the infarcted area, and compared this with a control, age-matched individual. Interestingly, a large number of neural stem cells, vascular endothelial growth factor-immunopositive cells and new blood vessels were observed only around the region of infarction, and none in the corresponding brain areas of the healthy control. In addition, an increased number of neural stem cells was observed in the neurogenic region of the lateral ventricle wall. Our results suggest increased endogenous neurogenesis associated with neovascularization and migration of newly-formed cells towards a region of cerebrovascular damage in the adult human brain and highlight possible mechanisms underlying this process.
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http://dx.doi.org/10.2217/17460751.2.1.69DOI Listing
January 2007

Altered neurogenesis in Alzheimer's disease.

J Psychosom Res 2006 Sep;61(3):311-6

Institute of Ageing and Health, University of Newcastle Upon Tyne, Newcastle General Hospital, Westgate Road, NE4 6BE Newcastle upon Tyne, UK.

Background: Exciting preliminary work indicates an increase in progenitor activity in the subgranular zone of the dentate gyrus of people with Alzheimer's disease (AD) compared to that of controls. We examine progenitor activity in the other main progenitor niche, the subventricular zone (SVZ), as well as potential associations with key pathological and neurochemical substrates.

Method: Immunocytochemistry techniques utilizing nestin and Musashi1 antibodies were used to examine progenitor activity in the SVZ and to enable comparisons between seven patients with AD and seven controls, based upon the quantification of the percentage area covered, using the Image Pro Plus v.4.1 image analysis system. AD pathology was staged using the Consortium to Establish a Registry for Alzheimer's Disease and Braak criteria. Choline acetyl transferase (ChAT) was measured in the temporal cortex as an indication of the severity of cortical cholinergic deficits. Glial fibrillary acidic protein (GFAP) was used to label astrocytes.

Results: There was a significant ninefold decrease (Z = 2.2, P = .046) of Musashi1 immunoreactivity in the SVZ of patients with AD in comparison with that of controls, but there was a significant increase in nestin immunoreactivity in the same region (Z = 2.2, P = .028) without any significant change in GFAP immunoreactivity. Reduced ChAT enzymatic activity was the main association of Musashi immunoreactivity (R = -.90, P = .03).

Discussion: The current results indicate a significant reduction of progenitor cells (as labeled by Musashi1) in the SVZ of patients with AD, but an increase in GFAP-negative astrocyte-like cells with progenitor characteristics. Cortical cholinergic loss was strongly associated with the reduction of progenitors, with potential implications of important treatment targets.
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http://dx.doi.org/10.1016/j.jpsychores.2006.07.017DOI Listing
September 2006

Selective effects of the APOE epsilon4 allele on presynaptic cholinergic markers in the neocortex of Alzheimer's disease.

Neurobiol Dis 2006 Jun 9;22(3):555-61. Epub 2006 Feb 9.

Dementia Research Laboratory, Department of Clinical Research, Singapore General Hospital, Outram Road, Singapore 169608, Singapore.

The effects of the APOE epsilon4 allele on a range of pre- and postsynaptic cholinergic markers were studied in a cohort of community-based Alzheimer's disease (AD) patients. Compared with age-matched controls, the postmortem AD neocortex showed decreased choline acetyltransferase (ChAT) and acetyl cholinesterase activities, lower muscarinic M2, and nicotinic alpha4beta2 receptor densities, as well as reduced M1 receptor coupling to G-proteins. However, the epsilon4 allele was dose-dependently correlated only with higher losses of ChAT activities. AD patients with two epsilon4 alleles also had more beta-amyloid containing senile plaques in the temporal cortex compared to patients with 0/1 epsilon4. This study suggests that APOE epsilon4 selectively affects presynaptic cholinergic function which may contribute to the clinical and neuropathological features of AD.
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http://dx.doi.org/10.1016/j.nbd.2005.12.016DOI Listing
June 2006

Derivation and characterization of four new human embryonic stem cell lines: the Danish experience.

Reprod Biomed Online 2006 Jan;12(1):119-26

Laboratory for Stem Cell Research, Aalborg University, Fredrik Bajers Vej 3B, 9220 Aalborg Oest, Denmark.

In September 2003, legislation approved in Denmark legalized work on surplus human embryos from IVF for clinical purposes to establish human embryonic stem (ES) cell cultures. The aim of this study was to establish such stem cell lines. Fresh surplus embryos were donated after informed consent from the donors. Embryos were cultured into blastocysts and using the immunosurgery procedure, inner cell masses were isolated and cultured on irradiated human foreskin fibroblasts in KnockOut D-MEM supplemented with KnockOut Serum Replacement, bFGF, and LIF. Within a period of 12 months, 198 embryos were donated. Four isolated inner cell masses developed into putative ES cell lines, CLS1, CLS2, CLS3, CLS4, which have now been continuously cultured for eight months, corresponding to 30 passages. These cells expressed markers for undifferentiated human ES cells: stage-specific embryonic antigen-4, tumour-related antigen (TRA)-1-60, TRA-1-81, OCT4, NANOG, SOX2, and FGF4. The cells expressed high levels of telomerase activity, had a normal karyotype, and have been successfully cryopreserved and thawed. Finally, the cells displayed the potential to differentiate in vitro into cell types originating from all three germ layers. It is thought that the cell lines described in this study are the first human ES cells established in Denmark.
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http://dx.doi.org/10.1016/s1472-6483(10)60990-xDOI Listing
January 2006

Regenerative medicine in Parkinson's disease: generation of mesencephalic dopaminergic cells from embryonic stem cells.

Curr Opin Biotechnol 2005 Oct;16(5):487-92

Stem Cell Biology Laboratory, Wolfson Centre for Age-Related Disease, King's College London, London SE1 1UL, UK.

Cell replacement therapy has been proposed as a means of replacing specific populations of cells lost through trauma, disease or ageing. Parkinson's disease is a progressive neurodegenerative disorder caused by the loss of midbrain dopaminergic neurons. Intrastriatal transplants of human foetal mesencephalic tissue in Parkinson's patients have demonstrated clinical efficacy, but the limited availability of tissue precludes systematic use of this treatment. Human embryonic stem cells are capable of unlimited self-renewal and can differentiate into cells representative of all three germ layers, including cells of the central nervous system. These cells may thus provide a relatively unlimited source of cells for transplantation, if appropriate differentiation protocols to generate highly enriched and specific populations of neural cells can be developed.
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http://dx.doi.org/10.1016/j.copbio.2005.08.005DOI Listing
October 2005

Stem cell therapy: hope or hype?

BMJ 2005 May;330(7501):1159-60

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http://dx.doi.org/10.1136/bmj.330.7501.1159DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC557997PMC
May 2005

Generation of a human embryonic stem cell line encoding the cystic fibrosis mutation deltaF508, using preimplantation genetic diagnosis.

Reprod Biomed Online 2005 Mar;10(3):390-7

Department of Women's Health, GKT School of Medicine, 10th Floor, North Wing, St Thomas' Hospital, London SE1 7EH, UK.

Human embryonic stem (hES) cells are pluripotent cells isolated from early human embryos. They can be grown in vitro and made to differentiate into many different cell types. These properties have suggested that they may be useful in cell replacement therapy for many degenerative diseases. However, if hES cells could also be manufactured with mutations significant in human disease, they could provide a powerful in-vitro tool for modelling disease processes and progression in a number of different cell types, as well as providing an ideal system for studying in-vitro toxicity and efficacy of drugs and other therapeutic systems such as gene therapy. Embryos with such mutations are generated as part of routine genetic testing during preimplantation genetic diagnosis, providing the opportunity to generate cell lines with significant mutations. A human embryonic stem cell line homozygous for the most common mutation leading to cystic fibrosis in humans (delta F508) has been generated and characterized. This cell line has the same morphology and expresses proteins typical of other unaffected hES cell lines. This cell line represents an important in-vitro tool for understanding the pathophysiology of cystic fibrosis, and presents exciting opportunities to test the efficacy and toxicity of new therapies relevant to CF.
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http://dx.doi.org/10.1016/s1472-6483(10)61801-9DOI Listing
March 2005

Generation of insulin-expressing cells from mouse embryonic stem cells.

Biochem Biophys Res Commun 2005 Mar;328(2):399-403

Beta Dell Development and Function Group, Division of Reproductive Health Endocrinology and Development, GKT School of Biomedical Sciences, King's College London, London SE1 1UL, UK.

The therapeutic potential of transplantation of insulin-secreting pancreatic beta-cells has stimulated interest in using pluripotent embryonic stem (ES) cells as a starting material from which to generate insulin secreting cells in vitro. Mature beta-cells are endodermal in origin so most reported differentiation protocols rely on the identification of endoderm-specific markers. However, endoderm development is an early event in embryogenesis that produces cells destined for the gut and associated organs in the embryo, and for the development of extra-embryonic structures such as the yolk sac. We have demonstrated that mouse ES cells readily differentiate into extra-embryonic endoderm in vitro, and that these cell populations express the insulin gene and other functional elements associated with beta-cells. We suggest that the insulin-expressing cells generated in this and other studies are not authentic pancreatic beta-cells, but may be of extra-embryonic endodermal origin.
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http://dx.doi.org/10.1016/j.bbrc.2004.12.183DOI Listing
March 2005

Timing of the retinoid-signalling pathway determines the expression of neuronal markers in neural progenitor cells.

Dev Biol 2005 Feb;278(1):60-70

Stem Cell Laboratory, The Wolfson Centre for Age Related Diseases, London SE1 1UL, UK.

By culturing neural progenitor cells in the presence of retinoid receptor agonists, we have defined the components of the retinoid-signalling pathway that are important for the birth and maintenance of neuronal cells. We provide evidence that depending on the order and combination of retinoid receptors activated, different neuronal cells are obtained. Astrocytes and oligodendrocytes are predominantly formed in the presence of activated retinoic acid receptor (RAR) alpha, whereas motoneurons are formed when RARbeta is activated. We have looked at the regulation of two transcription factors islet-1/2 which are involved in neuronal development. We find that activated RARbeta up-regulates islet-1 expression, whereas activation of RARalpha can either act in combination with RARbeta signalling to maintain islet-1 expression or induce islet-2 expression in the absence of activated RARbeta. RARgamma cannot directly regulate islet-1/2 but can down-regulate RARbeta expression, which results in loss of islet-1 expression. We finally show that activated RARalpha is one of the final steps required for a mature motoneuron phenotype.
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http://dx.doi.org/10.1016/j.ydbio.2004.10.015DOI Listing
February 2005

The in vitro differentiation of rat neural stem cells into an insulin-expressing phenotype.

Biochem Biophys Res Commun 2005 Jan;326(3):570-7

Beta Cell Development and Function Group, King's College London, London SE1 1UL, UK.

Mature beta-cells and nerve cells share many functional similarities despite originating from different embryonic germ layers. The aim of this study was to investigate the potential of neural stem cells (NSCs), isolated from foetal rat brain, as a starting material from which to generate functionally responsive, insulin-containing cells. Our results demonstrated that NSCs can be significantly expanded in vitro and can be induced to express increased preproinsulin mRNA levels. In addition, these NSC-derived cells expressed transcriptional and functional elements associated with a mature beta-cell phenotype. The differentiated cells showed functional responses typical of pancreatic beta-cells, including glucose-dependent increases in metabolism and rapid elevations in intracellular Ca(2+) in response to the sulphonylurea tolbutamide or to increased glucose concentration. These results suggest that NSCs may have potential as a starting material from which to generate beta-cell surrogates for the treatment of patients with Type 1 diabetes mellitus.
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http://dx.doi.org/10.1016/j.bbrc.2004.11.062DOI Listing
January 2005

Therapeutic potential of stem cells in central nervous system regeneration.

Curr Opin Investig Drugs 2004 Jul;5(7):714-9

Stem Cell Biology Laboratory, Wolfson Centre for Age Related Diseases, King's College London, London, UK.

Neurodegenerative disorders and traumatic brain injury result in the loss of specific neuronal populations. Stem cells are self-renewing, multi- or pluripotent cells capable of differentiating into a wide range of cell types, properties which make stem cells a potentially invaluable source of transplantable cells. Recent experimental studies have indicated that several stem cell populations have the ability to replace lost neurons and to repair the damaged nervous system following transplantation. This review evaluates the potential of various stem cell populations in the treatment of human neurodegenerative conditions and traumatic brain injury.
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July 2004

Changes in hippocampal SNAP-25 expression following afferent lesions.

Brain Res 2004 Jan;997(1):133-5

Department of Pharmacology, School of Medicine-University of Navarra, Irunlarrea 1, 31008 Pamplona, Spain.

Reductions in SNAP-25 immunohistochemistry were found after removing the glutamatergic and cholinergic inputs to the rat hippocampus. SNAP-25 levels were normalised by 1 month after afferent lesions. Surprisingly, a superimposed cholinergic lesions did not affect the return to normal SNAP-25 levels after a long-term entorhinal cortex lesion. It is concluded that changes in SNAP-25 may represent early markers of synaptic loss following afferent lesions to the hippocampus.
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http://dx.doi.org/10.1016/j.brainres.2003.10.045DOI Listing
January 2004

Glutamate receptor antagonists modulate heat shock protein response in focal brain ischemia.

Neurol Res 2003 Mar;25(2):201-7

Department of Neurology, University of Kentucky College of Medicine, Department of Veterans Affairs Medical Center, Lexington, Kentucky, USA.

Neurons and glia reacting to ischemic injury exhibit delayed expression of heat shock proteins (HSPs). We tested the hypothesis that glutamate receptor antagonists alter neuronal and glial activation during focal cerebral ischemia, as shown by spatio-temporal changes in HSP immunoreactivity. Rats underwent focal ischemia by permanent occlusion of the middle cerebral artery. All animals were pre-treated with NBQX (30 mg kg-1), a competitive antagonist of the AMPA/kainate receptor, or CGS-19755 (10 mg kg-1), a competitive NMDA receptor antagonist, and euthanatized after 6 or 24 h of ischemia to demonstrate regional immunoreactivity of HSP-72 or 32 in brain. Neurons immunolabeled for HSP-72 appeared in the penumbral region adjacent to the infarct at 24 h and increased in number and distribution after pretreatment with NBQX or CGS-19755. Immunolabeling for HSP-32 revealed that pre-treatment with CGS-19755 caused ramified glia to infiltrate the ischemic cortex at 6 h, a pattern that was not seen in ischemic controls until 24 h. Blockade of the NMDA or AMPA/kainate receptor modulates cellular stress responses in both neurons and glia within the developing infarct. We conclude that early, rather than delayed, expression of HSP-32 is a sensitive indicator of glial activation induced specifically by CGS-19755.
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http://dx.doi.org/10.1179/016164103101201201DOI Listing
March 2003

Noradrenergic changes, aggressive behavior, and cognition in patients with dementia.

Biol Psychiatry 2002 Mar;51(5):407-16

Dementia Research Laboratory, Centre for Neuroscience Research, GKT School of Biomedical Sciences, King's College, London, UK.

Background: We wished to examine the integrity of the noradrenergic system in patients with Alzheimer's disease, mixed/other dementias and controls, and possible relationships between changes in the noradrenergic system and the presence of behavioral and psychiatric signs and symptoms in dementia.

Methods: Alpha(2) adrenoceptor sites were measured by radioligand binding in three cortical regions of 46 individuals with dementia and 33 elderly normal controls together with cortical noradrenaline concentration and locus coeruleus cell and neurofibrillary tangle counts.

Results: The alpha(2) adrenergic receptor density was unaltered in patients with Alzheimer's disease, mixed/other dementias compared with controls; however, there was a loss of locus coeruleus cells in subjects with dementia, reaching 50% within the rostral nucleus. In addition, a significant reduction was seen in the midtemporal cortical noradrenaline concentration (31% decrease) in patients with Alzheimer's disease. In subjects with dementia, there was a positive correlation between aggressive behavior and magnitude of rostral locus coeruleus cell loss, while the reduction in noradrenaline concentration correlated with cognitive impairment.

Conclusions: Subgroups of patients with Alzheimer's disease may have different neurochemical changes from patients lacking these changes. Therefore, this study may have implications for the treatment of behavioral and psychiatric signs and symptoms in dementia, particularly aggressive behavior in patients with dementia.
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http://dx.doi.org/10.1016/s0006-3223(01)01235-5DOI Listing
March 2002