The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Susan C Barnett - One of the best experts on this subject based on the ideXlab platform.
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in vivo mri of Olfactory Ensheathing Cell grafts and regenerating axons in transplant mediated repair of the adult rat optic nerve
NMR in Biomedicine, 2012Co-Authors: Ioanna Sandvig, Susan C Barnett, Marte Thuen, Linh Hoang, Oystein Olsen, Thomas C P Sardella, Christian Brekken, Kare E Tvedt, Olav Haraldseth, M BerryAbstract:The purpose of the present study was to use magnetic resonance imaging (MRI) as a tool for monitoring transplant-mediated repair of the adult rat visual pathway. We labelled rat Olfactory Ensheathing Cells (OECs) using micron-sized particles of iron oxide (MPIO) and transplanted them by: i) intravitreal injection (ivit) and ii) intra-optic nerve (ON) injection (iON) in adult rats with ON crush (ONC) injury. We applied T(2)-weighted MRI and manganese-enhanced MRI (MEMRI) to visualise transplanted Cells and ON axons at specific times after injury and Cell engraftment. Our findings demonstrate that ivit MPIO-labelled OECs are unequivocally detected by T(2)-weighted MRI in vivo and that the T(1)-weighted 3D FLASH sequence applied for MEMRI facilitates simultaneous visualisation of Mn(2+-) enhanced regenerating retinal ganglion Cell (RGC) axons and MPIO-labelled OEC grafts. Furthermore, analysis of MRI data and ultrastructural findings supports the hypothesis that iON OEC transplants mediate regeneration and remyelination of RGC axons post injury.
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in vivo mri of Olfactory Ensheathing Cell grafts and regenerating axons in transplant mediated repair of the adult rat optic nerve
NMR in Biomedicine, 2012Co-Authors: Ioanna Sandvig, Susan C Barnett, Marte Thuen, Linh Hoang, Oystein Olsen, Thomas C P Sardella, Christian Brekken, Kare E Tvedt, Olav Haraldseth, M BerryAbstract:The purpose of the present study was to use magnetic resonance imaging (MRI) as a tool for monitoring transplant-mediated repair of the adult rat visual pathway. We labelled rat Olfactory ensheathi ...
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Olfactory mucosa for transplant mediated repair a complex tissue for a complex injury
Glia, 2010Co-Authors: Susan L Lindsay, J S Riddell, Susan C BarnettAbstract:Damage to the brain and spinal cord leads to permanent functional disability because of the very limited capacity of the central nervous system (CNS) for repair. Transplantation of Cells into regions of CNS damage represents one approach to enhancing this repair. At present, the ideal Cell type for transplant-mediated repair has not been identified but autologous transplantation would be advantageous. Olfactory tissue, in part because of its capacity for regeneration, has emerged as a promising source of Cells and several clinical centers are using Olfactory Cells or tissues in the treatment of CNS damage. Until now, the Olfactory Ensheathing Cell, a specialized glial Cell of the Olfactory system has been the main focus of attention. Transplants of this Cell have been shown to have a neuroprotective function, support axonal regeneration, and remyelinate demyelinated axons. However, the Olfactory mucosa is a heterogeneous tissue, composed of a variety of Cells supporting both its normal function and its regenerative capacity. It is therefore possible that it contains several Cell types that could participate in CNS repair including putative stem Cells as well as glia. Here we review the Cellular composition of the Olfactory tissue and the evidence that equivalent Cell types exist in both rodent and human Olfactory mucosa suggesting that it is potentially a rich source of autologous Cells for transplant-mediated repair of the CNS. © 2009 Wiley-Liss, Inc.
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fgf heparin differentially regulates schwann Cell and Olfactory Ensheathing Cell interactions with astrocytes a role in astrocytosis
The Journal of Neuroscience, 2007Co-Authors: Alessandra Santossilva, Richard Fairless, Andrew Toft, John S. Riddell, Paul Montague, Margaret C Frame, George M. Smith, Susan C BarnettAbstract:After injury, the CNS undergoes an astrocyte stress response characterized by reactive astrocytosis/proliferation, boundary formation, and increased glial fibrillary acidic protein (GFAP) and chondroitin sulfate proteoglycan (CSPG) expression. Previously, we showed that in vitro astrocytes exhibit this stress response when in contact with Schwann Cells but not Olfactory Ensheathing Cells (OECs). In this study, we confirm this finding in vivo by demonstrating that astrocytes mingle with OECs but not Schwann Cells after injection into normal spinal cord. We show that Schwann Cell-conditioned media (SCM) induces proliferation in monocultures of astrocytes and increases CSPG expression in a fibroblast growth factor receptor 1 (FGFR1)-independent manner. However, SCM added to OEC/astrocyte cocultures induces reactive astrocytosis and boundary formation, which, although sensitive to FGFR1 inhibition, was not induced by FGF2 alone. Addition of heparin to OEC/astrocyte cultures induces boundary formation, whereas heparinase or chlorate treatment of Schwann Cell/astrocyte cultures reduces it, suggesting that heparan sulfate proteoglycans (HSPGs) are modulating this activity. In vivo, FGF2 and FGFR1 immunoreactivity was increased over grafted OECs and Schwann Cells compared with the surrounding tissue, and HSPG immunoreactivity is increased over reactive astrocytes bordering the Schwann Cell graft. These data suggest that components of the astrocyte stress response, including boundary formation, astrocyte hypertrophy, and GFAP expression, are mediated by an FGF family member, whereas proliferation and CSPG expression are not. Furthermore, after Cell transplantation, HSPGs may be important for mediating the stress response in astrocytes via FGF2. Identification of factors secreted by Schwann Cells that induce this negative response in astrocytes would further our ability to manipulate the inhibitory environment induced after injury to promote regeneration.
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Olfactory Ensheathing Cell transplantation as a strategy for spinal cord repair what can it achieve
Nature Reviews Neurology, 2007Co-Authors: Susan C Barnett, J S RiddellAbstract:Numerous lines of evidence from animal studies indicate that transplants of Olfactory Ensheathing Cells—glial Cells derived from the Olfactory system—can promote functional recovery in the injured spinal cord. In this Review, Barnett and Riddell analyze this evidence and examine the mechanisms by which repair might be achieved, as well as assessing the prospects for translating this approach into the clinic. Restoring function to the injured spinal cord represents one of the most formidable challenges in regenerative medicine. Glial Cell transplantation is widely considered to be one of the most promising therapeutic strategies, and several differentiated glial Cell types—in particular, Schwann Cells and Olfactory Ensheathing Cells (OECs)—have been proposed as transplant candidates. In this Review, we analyze evidence from animal studies for improved functional recovery following transplantation of OECs into spinal cord injuries, and examine the mechanisms by which repair might be achieved. Data obtained using various injury models support the view that OEC transplants can promote functional recovery, but accumulating anatomical evidence indicates that although axons regenerate within a transplant, they do not cross the lesion or reconnect with neurons on the opposite side to any significant extent. Consequently, it is possible that neuroprotection and promotion of sprouting from intact fibers are the main mechanisms that contribute to functional recovery. We conclude that for the foreseeable future the clinical benefits of OEC transplants alone are likely to be modest. The future potential of Cell transplantation strategies will probably depend on the success with which the transplants can be combined with other, synergistic, therapies to achieve significant regeneration of axons and re-establish functionally useful connections across a spinal cord injury.
James Anthony St John - One of the best experts on this subject based on the ideXlab platform.
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liraglutide modulates Olfactory Ensheathing Cell migration with activation of erk and alteration of the extraCellular matrix
Biomedicine & Pharmacotherapy, 2021Co-Authors: Yuting Tseng, James Anthony St John, Mo Chen, Richard Lai, Francesca Oieni, Graham Smyth, Shailendra Anoopkumardukie, Jenny EkbergAbstract:Transplantation of Olfactory Ensheathing Cells (OECs) is a promising approach for repairing the injured nervous system that has been extensively trialed for nervous system repair. However, the method still needs improvement and optimization. One avenue of improving outcomes is to stimulate OEC migration into the injury site. Liraglutide is a glucagon-like peptide-1 receptor agonist used for management of diabetes and obesity. It has been shown to be neuroprotective and to promote Cell migration, but whether it can stimulate glial Cells remains unknown. In the current study, we investigated the effects of liraglutide on OEC migration and explored the involved mechanisms. We showed that liraglutide at low concentration (100 nM) overall promoted OEC migration over time. Liraglutide modulated the migratory behavior of OECs by reducing time in arrest, and promoted random rather than straight migration. Liraglutide also induced a morphological change of primary OECs towards a bipolar shape consistent with improved migration. We found that liraglutide activated extraCellular signal-regulated kinase (ERK), which has key roles in Cell migration; the timing of ERK activation correlated with stimulation of migration. Furthermore, liraglutide also modulated the extraCellular matrix by upregulating laminin-1 and down-regulating collagen IV. In summary, we found that liraglutide can stimulate OEC migration and re-model the extraCellular matrix to better promote Cell migration, and possibly also to become more conducive for axonal regeneration. Thus, liraglutide may improve OEC transplantation outcomes.
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reliable Cell purification and determination of Cell purity crucial aspects of Olfactory Ensheathing Cell transplantation for spinal cord repair
Neural Regeneration Research, 2020Co-Authors: Ronak Reshamwala, Megha Shah, Lucy Belt, Jenny Ekberg, James Anthony St JohnAbstract:Transplantation of Olfactory Ensheathing Cells, the glia of the primary Olfactory nervous system, has been trialed for spinal cord injury repair with promising but variable outcomes in animals and humans. Olfactory Ensheathing Cells can be harvested either from the lamina propria beneath the neuroepithelium in the nasal cavity, or from the Olfactory bulb in the brain. As these areas contain several other Cell types, isolating and purifying Olfactory Ensheathing Cells is a critical part of the process. It is largely unknown how contaminating Cells such as fibroblasts, other glial Cell types and supporting Cells affect Olfactory Ensheathing Cell function post-transplantation; these Cells may also cause unwanted side-effects. It is also, however, possible that the presence of some of the contaminant Cells can improve outcomes. Here, we reviewed the last decade of Olfactory Ensheathing Cell transplantation studies in rodents, with a focus on Olfactory Ensheathing Cell purity. We analyzed how purification methods and resultant Cell purity differed between Olfactory mucosa- and Olfactory bulb-derived Cell preparations. We analyzed how the studies reported on Olfactory Ensheathing Cell purity and which criteria were used to define Cells as Olfactory Ensheathing Cells. Finally, we analyzed the correlation between Cell purity and transplantation outcomes. We found that Olfactory bulb-derived Olfactory Ensheathing Cell preparations are typically purer than mucosa-derived preparations. We concluded that there is an association between high Olfactory Ensheathing Cell purity and favourable outcomes, but the lack of Olfactory Ensheathing Cell-specific markers severely hampers the field.
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the link between Olfactory Ensheathing Cell survival and spinal cord injury repair a commentary on common limitations of contemporary research
Neural Regeneration Research, 2020Co-Authors: Ronak Reshamwala, James Anthony St John, Megha Shah, Jenny EkbergAbstract:Olfactory Ensheathing Cells (OECs) are crucial players in the continuous regeneration of the Olfactory nervous system that occurs through out life and are thought to have unique growth-promoting properties. For this reason, OEC transplantation has been thoroughly explored for the potential to promote neural repair after both central and peripheral nervous system injuries. Numerous studies have shown that OEC transplantation is safe and can promote recovery after spinal cord injury (SCI), both in animal models and in human clinical trials. To date, a variety of injury types and time-points after injury, as well as different delivery methods, have been tested. Outcomes have been encouraging (in rodent models including, for example, restoration of locomotion, breathing and climbing ability along with induction of axonal sprouting and some axonal regeneration) but highly variable (Barnett and Riddell, 2007; Gomez et al., 2018). In their natural environment of the primary Olfactory nervous system (the Olfactory nerve and outer layer of the Olfactory bulb), OECs provide structural support for Olfactory axons and secrete a range of growth and guidance factors as well as basement membrane components. OECs also phagocytose debris arising from degenerating axons (Ekberg and St John, 2014). In the injured spinal cord, OECs (in addition to these functions) also exhibit a unique capacity for migration into scar tissue and for integration with astrocytes (Barnett and Riddell, 2007; Gomez et al., 2018). For these neural repair effects to occur, it is essential that the transplanted Cells survive over time. The key factor for success is thus that the OECs must not only arrive at the right place within the injury site, but must also over time integrate and interact with the injured tissue.
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optimizing Olfactory Ensheathing Cell transplantation for spinal cord injury repair
Journal of Neurotrauma, 2020Co-Authors: Aaron D Gilmour, Jenny Ekberg, Ronak Reshamwala, Alison Wright, James Anthony St JohnAbstract:Cell transplantation constitutes an important avenue for development of new treatments for spinal cord injury (SCI). These therapies are aimed at supporting neural repair and/or replacing lost Cells at the injury site. To date, various Cell types have been trialed, with most studies focusing on different types of stem Cells or glial Cells. Here, we review commonly used Cell transplantation approaches for spinal cord injury (SCI) repair, with focus on transplantation of Olfactory Ensheathing Cells (OECs), the glial Cells of the primary Olfactory nervous system. OECs are promising candidates for promotion of neural repair given that they support continuous regeneration of the Olfactory nerve that occurs throughout life. Further, OECs can be accessed from the nasal mucosa (Olfactory neuroepithelium) at the roof of the nasal cavity and can be autologously transplanted. OEC transplantation has been trialed in many animal models of SCI, as well as in human clinical trials. While several studies have been promising, outcomes are variable and the method needs improvement to enhance aspects such as Cell survival, integration, and migration. As a case study, we include the approaches used by our team (the Clem Jones Centre for Neurobiology and Stem Cell Research, Griffith University, Nathan, QLD, Australia) to address the current problems with OEC transplantation and discuss how the therapeutic potential of OEC transplantation can be improved. Our approach includes discovery research to improve our knowledge of OEC biology, identifying natural and synthetic compounds to stimulate the neural repair properties of OECs, and designing three-dimensional Cell constructs to create stable and transplantable Cell structures.
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three dimensional Cell culture can be regulated by vibration low frequency vibration increases the size of Olfactory Ensheathing Cell spheroids
Journal of Biological Engineering, 2019Co-Authors: Lachlan J Beckingham, Jenny Ekberg, Michael Todorovic, Johana Tello Velasquez, Marielaure Vial, Mo Chen, James Anthony St JohnAbstract:Olfactory Ensheathing Cell (OEC) transplantation is emerging as a promising therapy for spinal cord injuries. However, outcomes are inconsistent, and the method needs improvement. Currently, Cells are injected into the injury site as a suspension, and often fail to form a three-dimensional (3D) network crucial for both survival of the transplanted Cells, and for regeneration of severed axons. 3D culture systems are therefore likely to improve the method. Of the many 3D culture systems available, the spheroid-producing naked liquid marble (NLM) technique is particularly advantageous compared to other platforms as it rapidly generates Cell spheroids which can easily be extracted for further handling. To improve production of the spheroids, we designed and tested a device which allows fine control over vibrational stimuli to liquid marble Cell cultures. We applied vibrational frequencies of 20, 60, and 80 Hz with consistent amplitude to NLM containing OECs and assessed the size and number of the 3D Cell spheroids generated as well as the migratory capacity of Cells cultured in the vibrated spheroids. Vibrating the NLMs led to fewer and dramatically larger spheroids in comparison to non-vibrated NLMs. Of the frequencies tested, 60 Hz caused over 70-fold increase in spheroid volume. When transferred to a culture plate, the larger spheroids retained their structure after 72 h in culture, and Cells that migrated out of the spheroids covered a significantly larger area compared to Cells migrating out of spheroids formed at all the other frequencies tested. We have shown that vibration can be used to regulate the formation of Cell spheroids in NLM cultures. The ability to modulate the size of spheroids is useful for a range of 3D Cell culture models and for preparing Cells for in vivo transplantation.
J S Riddell - One of the best experts on this subject based on the ideXlab platform.
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Olfactory mucosa for transplant mediated repair a complex tissue for a complex injury
Glia, 2010Co-Authors: Susan L Lindsay, J S Riddell, Susan C BarnettAbstract:Damage to the brain and spinal cord leads to permanent functional disability because of the very limited capacity of the central nervous system (CNS) for repair. Transplantation of Cells into regions of CNS damage represents one approach to enhancing this repair. At present, the ideal Cell type for transplant-mediated repair has not been identified but autologous transplantation would be advantageous. Olfactory tissue, in part because of its capacity for regeneration, has emerged as a promising source of Cells and several clinical centers are using Olfactory Cells or tissues in the treatment of CNS damage. Until now, the Olfactory Ensheathing Cell, a specialized glial Cell of the Olfactory system has been the main focus of attention. Transplants of this Cell have been shown to have a neuroprotective function, support axonal regeneration, and remyelinate demyelinated axons. However, the Olfactory mucosa is a heterogeneous tissue, composed of a variety of Cells supporting both its normal function and its regenerative capacity. It is therefore possible that it contains several Cell types that could participate in CNS repair including putative stem Cells as well as glia. Here we review the Cellular composition of the Olfactory tissue and the evidence that equivalent Cell types exist in both rodent and human Olfactory mucosa suggesting that it is potentially a rich source of autologous Cells for transplant-mediated repair of the CNS. © 2009 Wiley-Liss, Inc.
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Olfactory Ensheathing Cell transplantation as a strategy for spinal cord repair what can it achieve
Nature Reviews Neurology, 2007Co-Authors: Susan C Barnett, J S RiddellAbstract:Numerous lines of evidence from animal studies indicate that transplants of Olfactory Ensheathing Cells—glial Cells derived from the Olfactory system—can promote functional recovery in the injured spinal cord. In this Review, Barnett and Riddell analyze this evidence and examine the mechanisms by which repair might be achieved, as well as assessing the prospects for translating this approach into the clinic. Restoring function to the injured spinal cord represents one of the most formidable challenges in regenerative medicine. Glial Cell transplantation is widely considered to be one of the most promising therapeutic strategies, and several differentiated glial Cell types—in particular, Schwann Cells and Olfactory Ensheathing Cells (OECs)—have been proposed as transplant candidates. In this Review, we analyze evidence from animal studies for improved functional recovery following transplantation of OECs into spinal cord injuries, and examine the mechanisms by which repair might be achieved. Data obtained using various injury models support the view that OEC transplants can promote functional recovery, but accumulating anatomical evidence indicates that although axons regenerate within a transplant, they do not cross the lesion or reconnect with neurons on the opposite side to any significant extent. Consequently, it is possible that neuroprotection and promotion of sprouting from intact fibers are the main mechanisms that contribute to functional recovery. We conclude that for the foreseeable future the clinical benefits of OEC transplants alone are likely to be modest. The future potential of Cell transplantation strategies will probably depend on the success with which the transplants can be combined with other, synergistic, therapies to achieve significant regeneration of axons and re-establish functionally useful connections across a spinal cord injury.
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Olfactory Ensheathing Cell grafts have minimal influence on regeneration at the dorsal root entry zone following rhizotomy
Glia, 2004Co-Authors: J S Riddell, Richard Fairless, Andrew Toft, Manuel Enriquezdenton, Susan C BarnettAbstract:The effectiveness of grafts of Olfactory Ensheathing Cells (OECs) as a means of promoting functional reconnection of regenerating primary afferent fibers was investigated following dorsal root injury. Adult rats were subjected to dorsal root section and reanastomosis and at the same operation a suspension of purified OECs was injected at the dorsal root entry zone and/or into the sectioned dorsal root. Regeneration of dorsal root fibers was then assessed after a survival period ranging from 1 to 6 months. In 11 animals, electrophysiology was used to look for evidence of functional reconnection of regenerating dorsal root fibers. However, electrical stimulation of lesioned dorsal roots failed to evoke detectable cord dorsum or field potentials within the spinal cord of any of the animals examined, indicating that reconnection of regenerating fibers with spinal cord neurones had not occurred. In a further 11 rats, immunocytochemical labeling and biotin dextran tracing of afferent fibers in the lesioned roots was used to determine whether regenerating fibers were able to grow into the spinal cord in the presence of an OEC graft. Although a few afferent fibers could be seen to extend for a limited distance into the spinal cord, similar minimal in-growth was seen in control animals that had not been injected with OECs. We therefore conclude that OEC grafts are of little or no advantage in promoting the in-growth of regenerating afferent fibers at the dorsal root entry zone following rhizotomy. © 2004 Wiley-Liss, Inc.
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Olfactory Ensheathing Cell grafts have minimal influence on regeneration at the dorsal root entry zone following rhizotomy
Glia, 2004Co-Authors: J S Riddell, Richard Fairless, Andrew Toft, Manuel Enriquezdenton, Susan C BarnettAbstract:The effectiveness of grafts of Olfactory Ensheathing Cells (OECs) as a means of promoting functional reconnection of regenerating primary afferent fibers was investigated following dorsal root injury. Adult rats were subjected to dorsal root section and reanastomosis and at the same operation a suspension of purified OECs was injected at the dorsal root entry zone and/or into the sectioned dorsal root. Regeneration of dorsal root fibers was then assessed after a survival period ranging from 1 to 6 months. In 11 animals, electrophysiology was used to look for evidence of functional reconnection of regenerating dorsal root fibers. However, electrical stimulation of lesioned dorsal roots failed to evoke detectable cord dorsum or field potentials within the spinal cord of any of the animals examined, indicating that reconnection of regenerating fibers with spinal cord neurones had not occurred. In a further 11 rats, immunocytochemical labeling and biotin dextran tracing of afferent fibers in the lesioned roots was used to determine whether regenerating fibers were able to grow into the spinal cord in the presence of an OEC graft. Although a few afferent fibers could be seen to extend for a limited distance into the spinal cord, similar minimal in-growth was seen in control animals that had not been injected with OECs. We therefore conclude that OEC grafts are of little or no advantage in promoting the in-growth of regenerating afferent fibers at the dorsal root entry zone following rhizotomy.
Ioanna Sandvig - One of the best experts on this subject based on the ideXlab platform.
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Effects of Neural Stem Cell and Olfactory Ensheathing Cell Co-transplants on Tissue Remodelling After Transient Focal Cerebral Ischemia in the Adult Rat
Neurochemical Research, 2017Co-Authors: Ingrid Lovise Augestad, Axel Karl Gottfrid Nyman, Alex Ignatius Costa, Susan Carol Barnett, Axel Sandvig, Asta Kristine Håberg, Ioanna SandvigAbstract:Effective transplant-mediated repair of ischemic brain lesions entails extensive tissue remodeling, especially in the ischemic core. Neural stem Cells (NSCs) are promising reparative candidates for stroke induced lesions, however, their survival and integration with the host-tissue post-transplantation is poor. In this study, we address this challenge by testing whether co-grafting of NSCs with Olfactory Ensheathing Cells (OECs), a special type of glia with proven neuroprotective, immunomodulatory, and angiogenic effects, can promote graft survival and host tissue remodelling. Transient focal cerebral ischemia was induced in adult rats by a 60-min middle cerebral artery occlusion (MCAo) followed by reperfusion. Ischemic lesions were verified by neurological testing and magnetic resonance imaging. Transplantation into the globus pallidus of NSCs alone or in combination with OECs was performed at two weeks post-MCAo, followed by histological analyses at three weeks post-transplantation. We found evidence of extensive vascular remodelling in the ischemic core as well as evidence of NSC motility away from the graft and into the infarct border in severely lesioned animals co-grafted with OECs. These findings support a possible role of OECs as part of an in situ tissue engineering paradigm for transplant mediated repair of ischemic brain lesions.
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in vivo mri of Olfactory Ensheathing Cell grafts and regenerating axons in transplant mediated repair of the adult rat optic nerve
NMR in Biomedicine, 2012Co-Authors: Ioanna Sandvig, Susan C Barnett, Marte Thuen, Linh Hoang, Oystein Olsen, Thomas C P Sardella, Christian Brekken, Kare E Tvedt, Olav Haraldseth, M BerryAbstract:The purpose of the present study was to use magnetic resonance imaging (MRI) as a tool for monitoring transplant-mediated repair of the adult rat visual pathway. We labelled rat Olfactory ensheathi ...
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in vivo mri of Olfactory Ensheathing Cell grafts and regenerating axons in transplant mediated repair of the adult rat optic nerve
NMR in Biomedicine, 2012Co-Authors: Ioanna Sandvig, Susan C Barnett, Marte Thuen, Linh Hoang, Oystein Olsen, Thomas C P Sardella, Christian Brekken, Kare E Tvedt, Olav Haraldseth, M BerryAbstract:The purpose of the present study was to use magnetic resonance imaging (MRI) as a tool for monitoring transplant-mediated repair of the adult rat visual pathway. We labelled rat Olfactory Ensheathing Cells (OECs) using micron-sized particles of iron oxide (MPIO) and transplanted them by: i) intravitreal injection (ivit) and ii) intra-optic nerve (ON) injection (iON) in adult rats with ON crush (ONC) injury. We applied T(2)-weighted MRI and manganese-enhanced MRI (MEMRI) to visualise transplanted Cells and ON axons at specific times after injury and Cell engraftment. Our findings demonstrate that ivit MPIO-labelled OECs are unequivocally detected by T(2)-weighted MRI in vivo and that the T(1)-weighted 3D FLASH sequence applied for MEMRI facilitates simultaneous visualisation of Mn(2+-) enhanced regenerating retinal ganglion Cell (RGC) axons and MPIO-labelled OEC grafts. Furthermore, analysis of MRI data and ultrastructural findings supports the hypothesis that iON OEC transplants mediate regeneration and remyelination of RGC axons post injury.
M Berry - One of the best experts on this subject based on the ideXlab platform.
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in vivo mri of Olfactory Ensheathing Cell grafts and regenerating axons in transplant mediated repair of the adult rat optic nerve
NMR in Biomedicine, 2012Co-Authors: Ioanna Sandvig, Susan C Barnett, Marte Thuen, Linh Hoang, Oystein Olsen, Thomas C P Sardella, Christian Brekken, Kare E Tvedt, Olav Haraldseth, M BerryAbstract:The purpose of the present study was to use magnetic resonance imaging (MRI) as a tool for monitoring transplant-mediated repair of the adult rat visual pathway. We labelled rat Olfactory ensheathi ...
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in vivo mri of Olfactory Ensheathing Cell grafts and regenerating axons in transplant mediated repair of the adult rat optic nerve
NMR in Biomedicine, 2012Co-Authors: Ioanna Sandvig, Susan C Barnett, Marte Thuen, Linh Hoang, Oystein Olsen, Thomas C P Sardella, Christian Brekken, Kare E Tvedt, Olav Haraldseth, M BerryAbstract:The purpose of the present study was to use magnetic resonance imaging (MRI) as a tool for monitoring transplant-mediated repair of the adult rat visual pathway. We labelled rat Olfactory Ensheathing Cells (OECs) using micron-sized particles of iron oxide (MPIO) and transplanted them by: i) intravitreal injection (ivit) and ii) intra-optic nerve (ON) injection (iON) in adult rats with ON crush (ONC) injury. We applied T(2)-weighted MRI and manganese-enhanced MRI (MEMRI) to visualise transplanted Cells and ON axons at specific times after injury and Cell engraftment. Our findings demonstrate that ivit MPIO-labelled OECs are unequivocally detected by T(2)-weighted MRI in vivo and that the T(1)-weighted 3D FLASH sequence applied for MEMRI facilitates simultaneous visualisation of Mn(2+-) enhanced regenerating retinal ganglion Cell (RGC) axons and MPIO-labelled OEC grafts. Furthermore, analysis of MRI data and ultrastructural findings supports the hypothesis that iON OEC transplants mediate regeneration and remyelination of RGC axons post injury.
