| 1. |
- Abbot, Stewart, et al.
(författare)
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Report of the international conference on manufacturing and testing of pluripotent stem cells
- 2018
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Ingår i: Biologicals. - : Elsevier BV. - 1045-1056. ; 56, s. 67-83
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Sessions included an overview of past cell therapy (CT) conferences sponsored by the International Alliance for Biological Standardization (IABS). The sessions highlighted challenges in the field of human pluripotent stem cells (hPSCs) and also addressed specific points on manufacturing, bioanalytics and comparability, tumorigenicity testing, storage, and shipping. Panel discussions complemented the presentations. The conference concluded that a range of new standardization groups is emerging that could help the field, but ways must be found to ensure that these efforts are coordinated. In addition, there are opportunities for regulatory convergence starting with a gap analysis of existing guidelines to determine what might be missing and what issues might be creating divergence. More specific global regulatory guidance, preferably from WHO, would be welcome. IABS and the California Institute for Regenerative Medicine (CIRM) will explore with stakeholders the development of a practical and innovative road map to support early CT product (CTP) developers.
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| 2. |
- Barker, Roger A, et al.
(författare)
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Are Stem Cell-Based Therapies for Parkinson's Disease Ready for the Clinic in 2016?
- 2016
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Ingår i: Journal of Parkinson's Disease. - 1877-718X. ; 6:1, s. 57-63
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Tidskriftsartikel (refereegranskat)abstract
- Recent news of an impending clinical cell transplantation trial in Parkinson's disease using parthenogenetic stem cells as a source of donor tissue have raised hopes in the patient community and sparked discussion in the research community. Based on discussions held by a global collaborative initiative on translation of stem cell therapy in Parkinson's disease, we have identified a set of key questions that we believe should be addressed ahead of every clinical stem cell-based transplantation trial in this disorder. In this article, we first provide a short history of cell therapy in Parkinson's disease and briefly describe the current state-of-art regarding human stem cell-derived dopamine neurons for use in any patient trial. With this background information as a foundation, we then discuss each of the key questions in relation to the upcoming therapeutic trial and critically assess if the time is ripe for clinical translation of parthenogenetic stem cell technology in Parkinson's disease.
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| 3. |
- Brambach, Max, et al.
(författare)
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Neural tube patterning : from a minimal model for rostrocaudal patterning toward an integrated 3D model
- 2021
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Ingår i: iScience. - : Elsevier BV. - 2589-0042. ; 24:6
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Tidskriftsartikel (refereegranskat)abstract
- Rostrocaudal patterning of the neural tube is a defining event in vertebrate brain development. This process is driven by morphogen gradients which specify the fate of neural progenitor cells, leading to the partitioning of the tube. Although this is extensively studied experimentally, an integrated view of the genetic circuitry is lacking. Here, we present a minimal gene regulatory model for rostrocaudal patterning, whose tristable topology was determined in a data-driven way. Using this model, we identified the repression of hindbrain fate as promising strategy for the improvement of current protocols for the generation of dopaminergic neurons. Furthermore, we combined our model with an established minimal model for dorsoventral patterning on a realistic 3D neural tube and found that key features of neural tube patterning could be recapitulated. Doing so, we demonstrate how data and models from different sources can be combined to simulate complex in vivo processes.
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| 4. |
- Cardoso, Tiago, et al.
(författare)
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Target-specific forebrain projections and appropriate synaptic inputs of hESC-derived dopamine neurons grafted to the midbrain of parkinsonian rats
- 2018
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Ingår i: Journal of Comparative Neurology. - 0021-9967. ; 526:13, s. 2133-2146
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Tidskriftsartikel (refereegranskat)abstract
- Dopamine (DA) neurons derived from human embryonic stem cells (hESCs) are a promising unlimited source of cells for cell replacement therapy in Parkinson's disease (PD). A number of studies have demonstrated functionality of DA neurons originating from hESCs when grafted to the striatum of rodent and non-human primate models of PD. However, several questions remain in regard to their axonal outgrowth potential and capacity to integrate into host circuitry. Here, ventral midbrain (VM) patterned hESC-derived progenitors were grafted into the midbrain of 6-hydroxydopamine-lesioned rats, and analyzed at 6, 18, and 24weeks for a time-course evaluation of specificity and extent of graft-derived fiber outgrowth as well as potential for functional recovery. To investigate synaptic integration of the transplanted cells, we used rabies-based monosynaptic tracing to reveal the origin and extent of host presynaptic inputs to grafts at 6 weeks. The results reveal the capacity of grafted neurons to extend axonal projections toward appropriate forebrain target structures progressively over 24weeks. The timing and extent of graft-derived dopaminergic fibers innervating the dorsolateral striatum matched reduction in amphetamine-induced rotational asymmetry in the animals where recovery could be observed. Monosynaptic tracing demonstrated that grafted cells integrate with host circuitry 6 weeks after transplantation, in a manner that is comparable with endogenous midbrain connectivity. Thus, we demonstrate that VM patterned hESC-derived progenitors grafted to midbrain have the capacity to extensively innervate appropriate forebrain targets, integrate into the host circuitry and that functional recovery can be achieved when grafting fetal or hESC-derived DA neurons to the midbrain.
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| 5. |
- Dubonyte, Ugne, et al.
(författare)
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Current advancements of modelling schizophrenia using patient-derived induced pluripotent stem cells
- 2022
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Ingår i: Acta Neuropathologica Communications. - : Springer Science and Business Media LLC. - 2051-5960. ; 10:1
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Forskningsöversikt (refereegranskat)abstract
- Schizophrenia (SZ) is a severe psychiatric disorder, with a prevalence of 1–2% world-wide and substantial health- and social care costs. The pathology is influenced by both genetic and environmental factors, however the underlying cause still remains elusive. SZ has symptoms including delusions, hallucinations, confused thoughts, diminished emotional responses, social withdrawal and anhedonia. The onset of psychosis is usually in late adolescence or early adulthood. Multiple genome-wide association and whole exome sequencing studies have provided extraordinary insights into the genetic variants underlying familial as well as polygenic forms of the disease. Nonetheless, a major limitation in schizophrenia research remains the lack of clinically relevant animal models, which in turn hampers the development of novel effective therapies for the patients. The emergence of human induced pluripotent stem cell (hiPSC) technology has allowed researchers to work with SZ patient-derived neuronal and glial cell types in vitro and to investigate the molecular basis of the disorder in a human neuronal context. In this review, we summarise findings from available studies using hiPSC-based neural models and discuss how these have provided new insights into molecular and cellular pathways of SZ. Further, we highlight different examples of how these models have shown alterations in neurogenesis, neuronal maturation, neuronal connectivity and synaptic impairment as well as mitochondrial dysfunction and dysregulation of miRNAs in SZ patient-derived cultures compared to controls. We discuss the pros and cons of these models and describe the potential of using such models for deciphering the contribution of specific human neural cell types to the development of the disease.
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| 6. |
- Elabi, Osama F, et al.
(författare)
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Human Embryonic Stem Cell-Derived Dopaminergic Grafts Alleviate L-DOPA Induced Dyskinesia
- 2022
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Ingår i: Journal of Parkinson's Disease. - 1877-718X. ; 12:6, s. 1881-1896
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: First-in-human studies to test the efficacy and safety of human embryonic stem cells (hESC)-derived dopaminergic cells in the treatment of Parkinson's disease (PD) are imminent. Pre-clinical studies using hESC-derived dopamine neuron transplants in rat models have indicated that the benefits parallel those shown with fetal tissue but have thus far failed to consider how ongoing L-DOPA administration might impact on the graft.OBJECTIVE: To determine whether L-DOPA impacts on survival and functional recovery following grafting of hESC-derived dopaminergic neurons.METHODS: Unilateral 6-OHDA lesioned rats were administered with either saline or L-DOPA prior to, and for 18 weeks following surgical implantation of dopaminergic neural progenitors derived from RC17 hESCs according to two distinct protocols in independent laboratories.RESULTS: Grafts from both protocols elicited reduction in amphetamine-induced rotations. Reduced L-DOPA-induced dyskinesia preceded the improvement in amphetamine-induced rotations. Furthermore, L-DOPA had no effect on overall survival (HuNu) or dopaminergic neuron content of the graft (TH positive cells) but did lead to an increase in the number of GIRK2 positive neurons.CONCLUSION: Critically, we found that L-DOPA was not detrimental to graft function, potentially enhancing graft maturation and promoting an A9 phenotype. Early improvement of L-DOPA-induced dyskinesia suggests that grafts may support the handling of exogenously supplied dopamine earlier than improvements in amphetamine-induced behaviours indicate. Given that one of the protocols will be employed in the production of cells for the European STEM-PD clinical trial, this is vital information for the management of patients and achieving optimal outcomes following transplantation of hESC-derived grafts for PD.
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| 7. |
- Garza, Raquel, et al.
(författare)
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Single-cell transcriptomics of human traumatic brain injury reveals activation of endogenous retroviruses in oligodendroglia
- 2023
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Ingår i: Cell Reports. - : Elsevier. - 2211-1247. ; 42:11, s. 113395-
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Tidskriftsartikel (refereegranskat)abstract
- Traumatic brain injury (TBI) is a leading cause of chronic brain impairment and results in a robust, but poorly understood, neuroinflammatory response that contributes to the long-term pathology. We used single-nuclei RNA sequencing (snRNA-seq) to study transcriptomic changes in different cell populations in human brain tissue obtained acutely after severe, life-threatening TBI. This revealed a unique transcriptional response in oligodendrocyte precursors and mature oligodendrocytes, including the activation of a robust innate immune response, indicating an important role for oligodendroglia in the initiation of neuroinflammation. The activation of an innate immune response correlated with transcriptional upregulation of endogenous retroviruses in oligodendroglia. This observation was causally linked in vitro using human glial progenitors, implicating these ancient viral sequences in human neuroinflammation. In summary, this work provides insight into the initiating events of the neuroinflammatory response in TBI, which has therapeutic implications.
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| 8. |
- Grealish, Shane, et al.
(författare)
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Human ESC-Derived Dopamine Neurons Show Similar Preclinical Efficacy and Potency to Fetal Neurons when Grafted in a Rat Model of Parkinson's Disease.
- 2014
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Ingår i: Cell Stem Cell. - : Elsevier BV. - 1934-5909. ; 15:5, s. 653-665
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Tidskriftsartikel (refereegranskat)abstract
- Considerable progress has been made in generating fully functional and transplantable dopamine neurons from human embryonic stem cells (hESCs). Before these cells can be used for cell replacement therapy in Parkinson's disease (PD), it is important to verify their functional properties and efficacy in animal models. Here we provide a comprehensive preclinical assessment of hESC-derived midbrain dopamine neurons in a rat model of PD. We show long-term survival and functionality using clinically relevant MRI and PET imaging techniques and demonstrate efficacy in restoration of motor function with a potency comparable to that seen with human fetal dopamine neurons. Furthermore, we show that hESC-derived dopamine neurons can project sufficiently long distances for use in humans, fully regenerate midbrain-to-forebrain projections, and innervate correct target structures. This provides strong preclinical support for clinical translation of hESC-derived dopamine neurons using approaches similar to those established with fetal cells for the treatment of Parkinson's disease.
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| 9. |
- Grealish, Shane, et al.
(författare)
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Monosynaptic Tracing using Modified Rabies Virus Reveals Early and Extensive Circuit Integration of Human Embryonic Stem Cell-Derived Neurons.
- 2015
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Ingår i: Stem Cell Reports. - : Elsevier BV. - 2213-6711. ; 4:6, s. 975-983
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Tidskriftsartikel (refereegranskat)abstract
- Human embryonic stem cell (hESC)-derived dopamine neurons are currently moving toward clinical use for Parkinson's disease (PD). However, the timing and extent at which stem cell-derived neurons functionally integrate into existing host neural circuitry after transplantation remain largely unknown. In this study, we use modified rabies virus to trace afferent and efferent connectivity of transplanted hESC-derived neurons in a rat model of PD and report that grafted human neurons integrate into the host neural circuitry in an unexpectedly rapid and extensive manner. The pattern of connectivity resembled that of local endogenous neurons, while ectopic connections were not detected. Revealing circuit integration of human dopamine neurons substantiates their potential use in clinical trials. Additionally, our data present rabies-based tracing as a valuable and widely applicable tool for analyzing graft connectivity that can easily be adapted to analyze connectivity of a variety of different neuronal sources and subtypes in different disease models.
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| 10. |
- Heuer, Andreas, et al.
(författare)
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HESC-derived neural progenitors prevent xenograft rejection through neonatal desensitisation
- 2016
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Ingår i: Experimental Neurology. - : Elsevier BV. - 0014-4886. ; 282, s. 78-85
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Tidskriftsartikel (refereegranskat)abstract
- Stem cell therapies for neurological disorders are rapidly moving towards use in clinical trials. Before initiation of clinical trials, extensive pre-clinical validation in appropriate animal models is essential. However, grafts of human cells into the rodent brain are rejected within weeks after transplantation and the standard methods of immune-suppression for the purpose of studying human xenografts are not always sufficient for the long-term studies needed for transplanted human neurons to maturate, integrate and provide functional benefits in the host brain. Neonatal injections in rat pups using human fetal brain cells have been shown to desensitise the host to accept human tissue grafts as adults, whilst not compromising their immune system. Here, we show that differentiated human embryonic stem cells (hESCs) can be used for desensitisation to achieve long-term graft survival of human stem cell-derived neurons in a xenograft setting, surpassing the time of conventional pharmacological immune-suppressive treatments. The use of hESCs for desensitisation opens up for a widespread use of the technique, which will be of great value when performing pre-clinical evaluation of stem cell-derived neurons in animal models.
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