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- Englund Johansson, Ulrica, et al.
(författare)
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Transplantation of human neural progenitor cells into the neonatal rat brain: extensive migration and differentiation with long-distance axonal projections.
- 2002
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Ingår i: Experimental Neurology. - : Elsevier BV. - 0014-4886 .- 1090-2430. ; 173:1, s. 1-21
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Tidskriftsartikel (refereegranskat)abstract
- Here we examined the ability of human neural progenitors from the embryonic forebrain, expanded for up to a year in culture in the presence of growth factors, to respond to environmental signals provided by the developing rat brain. After survival times of up to more than a year after transplantation into the striatum, the hippocampus, and the subventricular zone, the cells were analyzed using human-specific antisera and the reporter gene green fluorescent protein (GFP). From grafts implanted in the striatum, the cells migrated extensively, especially within white matter structures. Neuronal differentiation was most pronounced at the striatal graft core, with axonal projections extending caudally along the internal capsule into mesencephalon. In the hippocampus, cells migrated throughout the entire hippocampal formation and into adjacent white matter tracts, with differentiation into neurons both in the dentate gyrus and in the CA1-3 regions. Directed migration along the rostral migratory stream to the olfactory bulb and differentiation into granule cells were observed after implantation into the subventricular zone. Glial differentiation occurred at all three graft sites, predominantly at the injection sites, but also among the migrating cells. A lentiviral vector was used to transduce the cells with the GFP gene prior to grafting. The reporter gene was expressed for at least 15 weeks and the distribution of the gene product throughout the entire cytoplasmic compartment of the expressing cells allowed for a detailed morphological analysis of a portion of the grafted cells. The extensive integration and differentiation of in vitro-expanded human neural progenitor cells indicate that multipotent progenitors are capable of responding in a regionally specific manner to cues present in the developing rat brain.
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| 2. |
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| 3. |
- Fricker-Gates, R A, et al.
(författare)
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EGF infusion stimulates the proliferation and migration of embryonic progenitor cells transplanted in the adult rat striatum
- 2000
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Ingår i: Experimental Neurology. - : Elsevier BV. - 0014-4886. ; 165:2, s. 237-247
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Tidskriftsartikel (refereegranskat)abstract
- Immature progenitor cells (generated by in vitro propagation) may provide a useful alternative to primary cells (from dissected embryonic tissue) for transplantation if their migratory and proliferative and differentiation properties can be controlled and directed in vivo. In this study E15 murine EGF-responsive progenitor cells were transplanted to the striatum of adult rats. Simultaneously, these animals received continuous infusion of either epidermal growth factor (EGF) or vehicle, to the lateral ventricle, for 8 days. In animals that received EGF, the transplanted progenitors migrated toward the lateral ventricle and proliferated, as evidenced by bromodeoxyuridine incorporation. Progenitor cells transplanted to rats that received vehicle infusions showed neither of these responses. In all animals, transplanted progenitors expressed an immature astrocyte or oligodendrocyte phenotype, the majority of cells being astrocytes. We conclude that EGF stimulates the migration and proliferation of murine progenitor cells in vivo, either directly or indirectly, but does not influence their phenotypic differentiation.
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| 4. |
- Fricker-Gates, Rosemary A., et al.
(författare)
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Neural transplantation: restoring complex circuitry in the striatum
- 2001
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Ingår i: Restorative Neurology and Neuroscience. - 1878-3627. ; 19:1-2, s. 119-138
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Tidskriftsartikel (refereegranskat)abstract
- During the last 30 years, the promise of neural transplantation as a therapeutic strategy for neurodegenerative disease has been slowly recognised. Across the world, clinical transplants of embryonic primary dopamine neurones have been shown to ameliorate some of the motor deficits in Parkinson s disease (PD) patients, and more recently, systematic clinical trials have been initiated for the replacement of striatal projection neurones lost in Huntington's disease (HD). Clinical transplantation as a prospective therapy for HD poses a particular set of difficulties. The hallmarks of this neurodegenerative disease include extensive loss of medium spiny long-distance projection neurones of the caudate and putamen, affecting downstream target nuclei, the globus pallidus and substantia nigra, leading to dysregulation of motor control. In addition, extensive loss of cortical neurones that form the afferent systems to the basal ganglia leads to widespread cognitive decline. If transplantation therapy is to succeed in replacing degenerating neurones in HD and reinstating controlled function of complex basal gan-glia circuitry, the new neurones must be able to develop specific long-distance projections that can form accurate and functional connections with neurones in precise target regions. Our ongoing studies are aimed at addressing how we can improve the function of striatal transplants, in particular to optimise the reformation of precise long-distance connections and to re-establish normal motor and cognitive function. In particular, we have investigated optimal requirements for embryonic primary tissue to achieve these aims, and also the potential of other cell sources to provide long-distance projection neurones and reconnect complex circuitry. This review describes current progress of experiments to optimise the reconstruction of neuronal circuitry using primary embryonic tissue transplants, as well as our current initiatives to use neural stem cells or precursors to replace long distance projection neurones in the degenerating basal ganglia.
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