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Stem Cell Strategies in Promoting Neuronal Regeneration after Spinal Cord Injury: A Systematic Review. Int J Mol Sci 2022; 23:ijms232112996. [PMID: 36361786 PMCID: PMC9657320 DOI: 10.3390/ijms232112996] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2022] [Revised: 10/09/2022] [Accepted: 10/25/2022] [Indexed: 11/25/2022] Open
Abstract
Spinal cord injury (SCI) is a devastating condition with a significant medical and socioeconomic impact. To date, no effective treatment is available that can enable neuronal regeneration and recovery of function at the damaged level. This is thought to be due to scar formation, axonal degeneration and a strong inflammatory response inducing a loss of neurons followed by a cascade of events that leads to further spinal cord damage. Many experimental studies demonstrate the therapeutic effect of stem cells in SCI due to their ability to differentiate into neuronal cells and release neurotrophic factors. Therefore, it appears to be a valid strategy to use in the field of regenerative medicine. This review aims to provide an up-to-date summary of the current research status, challenges, and future directions for stem cell therapy in SCI models, providing an overview of this constantly evolving and promising field.
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Peña JS, Robles D, Zhang S, Vazquez M. A Milled Microdevice to Advance Glia-Mediated Therapies in the Adult Nervous System. MICROMACHINES 2019; 10:mi10080513. [PMID: 31370352 PMCID: PMC6723365 DOI: 10.3390/mi10080513] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Revised: 07/19/2019] [Accepted: 07/29/2019] [Indexed: 12/18/2022]
Abstract
Neurodegenerative disorders affect millions of adults worldwide. Neuroglia have become recent therapeutic targets due to their reparative abilities in the recycling of exogenous neurotoxins and production of endogenous growth factors for proper functioning of the adult nervous system (NS). Since neuroglia respond effectively to stimuli within in vivo environments on the micron scale, adult glial physiology has remarkable synergy with microscale systems. While clinical studies have begun to explore the reparative action of Müller glia (MG) of the visual system and Schwann Cells (ShC) of the peripheral NS after neural injury, few platforms enable the study of intrinsic neuroglia responses to changes in the local microenvironment. This project developed a low-cost, benchtop-friendly microfluidic system called the glia line system, or gLL, to advance the cellular study needed for emerging glial-based therapies. The gLL was fabricated using elastomeric kits coupled with a metal mold milled via conventional computer numerical controlled (CNC) machines. Experiments used the gLL to measure the viability, adhesion, proliferation, and migration of MG and ShC within scales similar to their respective in vivo microenvironments. Results illustrate differences in neuroglia adhesion patterns and chemotactic behavior significant to advances in regenerative medicine using implants and biomaterials, as well as cell transplantation techniques. Data showed highest survival and proliferation of MG and ShC upon laminin and illustrated a four-fold and two-fold increase of MG migration to dosage-dependent signaling from vascular endothelial growth factor (VEGF) and epidermal growth factor (EGF), respectively, as well as a 20-fold increase of ShC migration toward exogenous brain-derived neurotrophic factor (BDNF), compared to media control. The ability to quantify these biological parameters within the gLL offers an effective and reliable alternative to photolithography study neuroglia in a local environment ranging from the tens to hundreds of microns, using a low-cost and easily fabricated system.
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Affiliation(s)
- Juan S Peña
- Department of Biomedical Engineering, Rutgers, The State University of New Jersey, New Brunswick, NJ 08901, USA
| | - Denise Robles
- Department of Biomedical Engineering, Rutgers, The State University of New Jersey, New Brunswick, NJ 08901, USA
| | - Stephanie Zhang
- Department of Biomedical Engineering, State University of New York at Binghamton, Binghamton, NY 13902, USA
| | - Maribel Vazquez
- Department of Biomedical Engineering, Rutgers, The State University of New Jersey, New Brunswick, NJ 08901, USA.
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Multichannel polymer scaffold seeded with activated Schwann cells and bone mesenchymal stem cells improves axonal regeneration and functional recovery after rat spinal cord injury. Acta Pharmacol Sin 2017; 38:623-637. [PMID: 28392569 DOI: 10.1038/aps.2017.11] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Accepted: 01/23/2017] [Indexed: 12/17/2022] Open
Abstract
The adult mammalian CNS has a limited capacity to regenerate after traumatic injury. In this study, a combinatorial strategy to promote axonal regeneration and functional recovery after spinal cord injury (SCI) was evaluated in adult rats. The rats were subjected to a complete transection in the thoracic spinal cord, and multichannel scaffolds seeded with activated Schwann cells (ASCs) and/or rat bone marrow-derived mesenchymal stem cells (MSCs) were acutely grafted into the 3-mm-wide transection gap. At 4 weeks post-transplantation and thereafter, the rats receiving scaffolds seeded with ASCs and MSCs exhibited significant recovery of nerve function as shown by the Basso, Beattie and Bresnahan (BBB) score and electrophysiological test results. Immunohistochemical analyses at 4 and 8 weeks after transplantation revealed that the implanted MSCs at the lesion/graft site survived and differentiated into neuron-like cells and co-localized with host neurons. Robust bundles of regenerated fibers were identified in the lesion/graft site in the ASC and MSC co-transplantation rats, and neurofilament 200 (NF) staining confirmed that these fibers were axons. Furthermore, myelin basic protein (MBP)-positive myelin sheaths were also identified at the lesion/graft site and confirmed via electron microscopy. In addition to expressing mature neuronal markers, sparse MSC-derived neuron-like cells expressed choline acetyltransferase (ChAT) at the injury site of the ASC and MSC co-transplantation rats. These findings suggest that co-transplantation of ASCs and MSCs in a multichannel polymer scaffold may represent a novel combinatorial strategy for the treatment of spinal cord injury.
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Marcol W, Ślusarczyk W, Larysz-Brysz M, Francuz T, Jędrzejowska-Szypułka H, Łabuzek K, Lewin-Kowalik J. Grafted Activated Schwann Cells Support Survival of Injured Rat Spinal Cord White Matter. World Neurosurg 2015; 84:511-9. [PMID: 25910924 DOI: 10.1016/j.wneu.2015.04.027] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Revised: 04/10/2015] [Accepted: 04/11/2015] [Indexed: 01/09/2023]
Abstract
BACKGROUND AND OBJECTIVE The influence of cultured Schwann cells on injured spinal cord in rats is examined. METHODS Focal injury of spinal cord white matter at the T10 level was produced using our original non-laminectomy method with a high-pressure air stream. Schwann cells from 7-day predegenerated rat sciatic nerves were cultured, transducted with green fluorescent protein and injected into the cisterna magna (experimental group) 3 times: immediately after spinal cord injury and 3 and 7 days later. Neurons in the brainstem and motor cortex were labeled with FluoroGold (FG) delivered caudally from the injury site a week before the end of the experiment. The functional outcome and morphologic features of neuronal survival were analyzed during a 12-week follow-up. The lesions were visualized and analyzed using magnetic resonance imaging. The maximal distance of expansion of implanted cells in the spinal cord was measured and the number of FG-positive neurons in the brain was counted. RESULTS Rats treated with Schwann cells presented significant improvement of locomotor performance and spinal cord morphology compared with the control group. The distance covered by Schwann cells was 7 mm from the epicenter of the injury. The number of brainstem and motor cortex FG-positive neurons in the experimental group was significantly higher than in the control group. CONCLUSIONS The data show that activated Schwann cells are able to induce the repair of injured spinal cord white matter. The route of application of cells via the cisterna magna seemed to be useful for their delivery in spinal cord injury therapy.
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Affiliation(s)
- Wiesław Marcol
- Department of Physiology, School of Medicine in Katowice, Medical University of Silesia, Katowice, Poland.
| | - Wojciech Ślusarczyk
- Department of Physiology, School of Medicine in Katowice, Medical University of Silesia, Katowice, Poland
| | - Magdalena Larysz-Brysz
- Department of Physiology, School of Medicine in Katowice, Medical University of Silesia, Katowice, Poland
| | - Tomasz Francuz
- Department of Biochemistry, School of Medicine in Katowice, Medical University of Silesia, Katowice, Poland
| | | | - Krzysztof Łabuzek
- Department of Pharmacology, School of Medicine in Katowice, Medical University of Silesia, Katowice, Poland
| | - Joanna Lewin-Kowalik
- Department of Physiology, School of Medicine in Katowice, Medical University of Silesia, Katowice, Poland
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Deng LX, Walker C, Xu XM. Schwann cell transplantation and descending propriospinal regeneration after spinal cord injury. Brain Res 2014; 1619:104-14. [PMID: 25257034 DOI: 10.1016/j.brainres.2014.09.038] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Revised: 09/08/2014] [Accepted: 09/15/2014] [Indexed: 01/15/2023]
Abstract
After spinal cord injury (SCI), poor ability of damaged axons of the central nervous system (CNS) to regenerate causes very limited functional recovery. Schwann cells (SCs) have been widely explored as promising donors for transplantation to promote axonal regeneration in the CNS including the spinal cord. Compared with other CNS axonal pathways, injured propriospinal tracts display the strongest regenerative response to SC transplantation. Even without providing additional neurotrophic factors, propriospinal axons can grow into the SC environment which is rarely seen in supraspinal tracts. Propriospinal tract has been found to respond to several important neurotrophic factors secreted by SCs. Therefore, the SC is considered to be one of the most promising candidates for cell-based therapies for SCI. Since many reviews have already appeared on topics of SC transplantation in SCI repair, this review will focus particularly on the rationale of SC transplantation in mediating descending propriospinal axonal regeneration as well as optimizing such regeneration by using different combinatorial strategies. This article is part of a Special Issue entitled SI: Spinal cord injury.
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Affiliation(s)
- Ling-Xiao Deng
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, IN 46202, USA; Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Department of Neurological Surgery, Goodman and Campbell Brain and Spine, Indiana University School of Medicine, Indianapolis, IN 46202, USA.
| | - Chandler Walker
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Department of Neurological Surgery, Goodman and Campbell Brain and Spine, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Xiao-Ming Xu
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, IN 46202, USA; Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Department of Neurological Surgery, Goodman and Campbell Brain and Spine, Indiana University School of Medicine, Indianapolis, IN 46202, USA
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Hill CE, Brodak DM, Bartlett Bunge M. Dissociated predegenerated peripheral nerve transplants for spinal cord injury repair: a comprehensive assessment of their effects on regeneration and functional recovery compared to Schwann cell transplants. J Neurotrauma 2012; 29:2226-43. [PMID: 22655857 DOI: 10.1089/neu.2012.2377] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Several recent studies suggest that predegenerated nerves (PDNs) or dissociated PDNs (dPDNs) can improve behavioral and histological outcomes following transplantation into the injured rat spinal cord. In the current study we tested the efficacy of dPDN transplantation by grafting cells isolated from the sciatic nerve 7 days after crush. We did not replicate one study, but rather assessed what appeared, based on five published reports, to be a reported robust effect of dPDN grafts on corticospinal tract (CST) regeneration and locomotor recovery. Using a standardized rodent spinal cord injury model (200 kD IH contusion) and transplantation procedure (injection of GFP⁺ cells 7 days post-SCI), we demonstrate that dPDN grafts survive within the injured spinal cord and promote the ingrowth of axons to a similar extent as purified Schwann cell (SC) grafts. We also demonstrate for the first time that while both dPDN and SC grafts promote the ingrowth of CGRP axons, neither graft results in mechanical or thermal hyperalgesia. Unlike previous studies, dPDN grafts did not promote long-distance axonal growth of CST axons, brainstem spinal axons, or ascending dorsal column sensory axons. Moreover, using a battery of locomotor tests (Basso Beattie Bresnahan [BBB] score, BBB subscore, inked footprint, Catwalk, and ladderwalk), we failed to detect any beneficial effects of dPDN transplantation on the recovery of locomotor function after SCI. We conclude that dPDN transplants are not sufficient to promote CST regeneration or locomotor recovery after SCI.
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Affiliation(s)
- Caitlin E Hill
- The Burke Medical Research Institute, 785 Mamaroneck Avenue, White Plains, NY 10605, USA.
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Saberi H, Firouzi M, Habibi Z, Moshayedi P, Aghayan HR, Arjmand B, Hosseini K, Razavi HE, Yekaninejad MS. Safety of intramedullary Schwann cell transplantation for postrehabilitation spinal cord injuries: 2-year follow-up of 33 cases. J Neurosurg Spine 2011; 15:515-25. [PMID: 21800956 DOI: 10.3171/2011.6.spine10917] [Citation(s) in RCA: 89] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECT Many experimental studies on spinal cord injuries (SCIs) support behavioral improvement after Schwann cell treatment. This study was conducted to evaluate safety issues 2 years after intramedullary Schwann cell transplantation in 33 consecutively selected patients with SCI. METHODS Of 356 patients with SCIs who had completed at least 6 months of a conventional rehabilitation program and who were screened for the study criteria, 33 were enrolled. After giving their informed consent, they volunteered for participation. They underwent sural nerve harvesting and intramedullary injection of a processed Schwann cell solution. Outcome assessments included a general health questionnaire, neurological examination, and functional recordings in terms of American Spinal Injury Association (ASIA) and Functional Independence Measure scoring, which were documented by independent observers. There were 24 patients with thoracic and 9 with cervical injuries. Sixteen patients were categorized in ASIA Grade A, and the 17 remaining participants had ASIA Grade B. RESULTS There were no cases of deep infection, and the follow-up MR imaging studies obtained at 2 years did not reveal any deformity related to the procedure. There was no case of permanent neurological worsening or any infectious or viral complications. No new increment in syrinx size or abnormal tissue and/or tumor formation were observed on contrast-enhanced MR imaging studies performed 2 years after the treatment. CONCLUSIONS Preliminary results, especially in terms of safety, seem to be promising, paving the way for future cell therapy trials.
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Affiliation(s)
- Hooshang Saberi
- Department of Neurosurgery, Imam Khomeini Hospital, Tehran University of Medical Sciences, Tehran, Iran.
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Tapadia M, Mozaffar T, Gupta R. Compressive neuropathies of the upper extremity: update on pathophysiology, classification, and electrodiagnostic findings. J Hand Surg Am 2010; 35:668-77. [PMID: 20223605 PMCID: PMC4715364 DOI: 10.1016/j.jhsa.2010.01.007] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/27/2009] [Accepted: 01/12/2010] [Indexed: 02/02/2023]
Abstract
Clinical examination and electrodiagnostic studies remain the gold standard for diagnosis of nerve injuries. Diagnosis of chronic nerve compression (CNC) injuries can be difficult in patients with confounding factors such as diabetes. The treatment of nerve entrapment ranges from medical to surgical management, depending on the nerve involved and on the severity and duration of compression. Considerable insights have been made at the molecular level, differentiating between nerve crush injuries and CNC injuries. Although the myelin changes after CNC injury were previously thought to be a mild form of Wallerian degeneration, recent evidence points to a distinct pathophysiology involving Schwann cell mechanosensitivity. Future areas of research include Schwann cell transplantation in the treatment regimen, the correlation between demyelination and the onset of pain, and the role of Schwann cell integrins in transducing the mechanical forces involved in nerve compression injuries to Schwann cells.
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Affiliation(s)
- Minal Tapadia
- Peripheral Nerve Research Laboratory, University of California, Irvine; Irvine, CA
| | - Tahseen Mozaffar
- Department of Neurology, University of California, Irvine; Irvine, CA
- Peripheral Nerve Research Laboratory, University of California, Irvine; Irvine, CA
| | - Ranjan Gupta
- Department of Orthopaedic Surgery, University of California, Irvine; Irvine, CA
- Department of Anatomy and Neurobiology, University of California, Irvine; Irvine, CA
- Department of Biomedical Engineering, University of California, Irvine; Irvine, CA
- Peripheral Nerve Research Laboratory, University of California, Irvine; Irvine, CA
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Abstract
Historically, clinical outcomes following spinal cord injury have been dismal. Over the past 20 years, the survival rate and long-term outcome of patients with spinal cord injury have improved with advances in both medical and surgical treatment. However, the efficacy and timing of these adjuvant treatments remain controversial. There has been a tremendous increase in the number of basic science and clinical studies on spinal cord injury. Current areas of investigation include early acute management, including early surgical intervention, as well as new pharmacotherapy and cellular transplantation strategies. It is unlikely that a single approach can uniformly address all of the issues associated with spinal cord injury. Thus, a multidisciplinary approach will be needed.
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Xu XM, Onifer SM. Transplantation-mediated strategies to promote axonal regeneration following spinal cord injury. Respir Physiol Neurobiol 2009; 169:171-82. [PMID: 19665611 PMCID: PMC2800078 DOI: 10.1016/j.resp.2009.07.016] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2009] [Revised: 07/16/2009] [Accepted: 07/20/2009] [Indexed: 12/19/2022]
Abstract
Devastating central nervous system injuries and diseases continue to occur in spite of the tremendous efforts of various prevention programs. The enormity and annual escalation of healthcare costs due to them require that therapeutic strategies be responsibly developed. The dysfunctions that occur after injury and disease are primarily due to neurotransmission damage. The last two decades of both experimental and clinical research have demonstrated that neural and non-neural tissue and cell transplantation is a viable option for ameliorating dysfunctions to markedly improve quality of life. Moreover, significant progress has been made with tissue and cell transplantation in studies of pathophysiology, plasticity, sprouting, regeneration, and functional recovery. This article will review information about the ability and potential, particularly for traumatic spinal cord injury, that neural and non-neural tissue and cell transplantation has to replace lost neurons and glia, to reconstruct damaged neural circuitry, and to restore neurotransmitters, hormones, neurotrophic factors, and neurotransmission. Donor tissues and cells to be discussed include peripheral nerve, fetal spinal cord and brain, central and peripheral nervous systems' glia, stem cells, those that have been genetically engineered, and non-neural ones. Combinatorial approaches and clinical research are also reviewed.
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Affiliation(s)
- Xiao-Ming Xu
- Spinal Cord and Brain Injury Research Group, Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, IN 46202, United States.
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Rasouli A, Bhatia N, Dinh P, Cahill K, Suryadevara S, Gupta R. Resection of glial scar following spinal cord injury. J Orthop Res 2009; 27:931-6. [PMID: 19062171 PMCID: PMC2696557 DOI: 10.1002/jor.20793] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
While many studies have focused on modulating the immune response and enhancing axonal regeneration after spinal cord injury (SCI), there is limited work being performed on evaluating the role of glial scar in SCI. We sought to evaluate the effects of glial scar resection in contusion models and dorsal hemisection models of SCI. At 1-week postinjury, 2 mm of glial scar was excised from specimens in one of the two groups from each injury model. Functional outcome was measured weekly using the Basso, Beattie, Bresnahan (BBB) Locomotor Rating Scale along with histologic evaluation of spinal cord tracts to determine axonal regeneration. Within the dorsal hemisection model, there was no significant difference in recovery for animals that underwent glial scar excision versus animals that did not have scar excision (p = 0.61). Animals subjected to the contusion model, however, demonstrated lower BBB scores in the glial resection group during the earlier postoperative periods (< 4 weeks; p < 0.05). Histological analysis revealed no axons within the glial resection contusion model, and moderate axonal growth within the nonresection contusion group and both hemisection groups (p > 0.05 for differences among the three groups). While glial scar may serve to stabilize the preserved axonal tracts and thereby permit modest recovery in a contusion model of SCI, it may be of less importance with a dorsal hemisection model. These experiments highlight that basic biologic processes following SCI may vary tremendously based on the injury mechanism and that the role of glial scar in spinal cord regeneration must be elucidated.
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Affiliation(s)
| | | | - Paul Dinh
- Department of Anatomy and Neurobiology
| | | | | | - Ranjan Gupta
- Department of Anatomy and Neurobiology, Department of Biomedical Engineering, University of California, Irvine,Corresponding Author: Ranjan Gupta, MD, 2226 Gillespie Neuroscience Research Facility, Irvine, CA 92697, Phone: 949-824-1405, Fax: 949-824-1462,
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Nomura H, Baladie B, Katayama Y, Morshead CM, Shoichet MS, Tator CH. Delayed implantation of intramedullary chitosan channels containing nerve grafts promotes extensive axonal regeneration after spinal cord injury. Neurosurgery 2009; 63:127-41; discussion 141-3. [PMID: 18728578 DOI: 10.1227/01.neu.0000335080.47352.31] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
OBJECTIVE We describe a new strategy to promote axonal regeneration after subacute or chronic spinal cord injury consisting of intramedullary implantation of chitosan guidance channels containing peripheral nerve (PN) grafts. METHODS Chitosan channels filled with PN grafts harvested from green fluorescent protein rats were implanted in the cavity 1 week (subacute) or 4 weeks (chronic) after 50-g clip injury at T8 and were compared with similarly injured animals implanted with either unfilled channels or no channels. Functional recovery was measured weekly for 12 weeks by open-field locomotion, after which histological examination was performed. RESULTS The implanted channels with PN grafts contained a thick tissue bridge containing as many as 35,000 myelinated axons in both the subacute and chronic spinal cord injury groups, with the greatest number of axons in the channels containing PN grafts implanted subacutely. There were numerous green fluorescent protein-positive donor Schwann cells in the tissue bridges in all animals with PN grafts. Moreover, these Schwann cells had high functional capacity in terms of myelination of the axons in the channels. In addition, PN-filled chitosan channels showed excellent biocompatibility with the adjacent neural tissue and no obvious signs of degradation and minimal tissue reaction at 14 weeks after implantation. In control animals that had unfilled chitosan channels implanted, there was minimal axonal regeneration in the channels; in control animals without channels, there were large cavities in the spinal cords, and the bridges contained only a small number of axons and Schwann cells. Despite the large numbers of axons in the chitosan channel-PN graft group, there was no significant difference in functional recovery between treatment and control groups. CONCLUSION Intramedullary implantation of chitosan guidance channels containing PN grafts in the cavity after subacute spinal cord injury resulted in a thicker bridge containing a larger number of myelinated axons compared with chitosan channels alone. A chitosan channel containing PN grafts is a promising strategy for spinal cord repair.
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Affiliation(s)
- Hiroshi Nomura
- Toronto Western Research Institute, Toronto Western Hospital, Toronto, Canada
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Nomura H, Baladie B, Katayama Y, Morshead CM, Shoichet MS, Tator CH. DELAYED IMPLANTATION OF INTRAMEDULLARY CHITOSAN CHANNELS CONTAINING NERVE GRAFTS PROMOTES EXTENSIVE AXONAL REGENERATION AFTER SPINAL CORD INJURY. Neurosurgery 2008. [DOI: 10.1227/01.neu.0000316443.88403.16] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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Li GN, Hoffman-Kim D. Tissue-Engineered Platforms of Axon Guidance. TISSUE ENGINEERING PART B-REVIEWS 2008; 14:33-51. [DOI: 10.1089/teb.2007.0181] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Affiliation(s)
- Grace N. Li
- Department of Molecular Pharmacology, Physiology, and Biotechnology, Brown University, Providence, Rhode Island
| | - Diane Hoffman-Kim
- Department of Molecular Pharmacology, Physiology, and Biotechnology, Brown University, Providence, Rhode Island
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Sandrow HR, Shumsky JS, Amin A, Houle JD. Aspiration of a cervical spinal contusion injury in preparation for delayed peripheral nerve grafting does not impair forelimb behavior or axon regeneration. Exp Neurol 2007; 210:489-500. [PMID: 18295206 DOI: 10.1016/j.expneurol.2007.11.029] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2007] [Revised: 11/21/2007] [Accepted: 11/26/2007] [Indexed: 01/17/2023]
Abstract
A peripheral nerve graft model was used to examine axonal growth after a unilateral cervical (C) contusion injury in adult rats and to determine if manipulation of an injury site prior to transplantation affects spontaneous behavioral recovery. After a short delay (7 d) the epicenter of a C4 contusion was exposed and aspirated without harming the cavity walls followed by apposition with one end of a pre-degenerated tibial nerve to the rostral cavity wall. After a longer delay (28 d) the aspirated cavity was treated with GDNF to promote regeneration by chronically injured neurons. In both groups forelimb and hindlimb locomotor scores decreased significantly 2 d after lesion site manipulation, but by 7 d, the forelimb score was not different from the pre-manipulation score. There was no significant difference in grid walking or grip strength scores for the affected forelimb in either group 7 d after contusion vs. 7 d after manipulation. Over 1500 brain stem and propriospinal neurons grew axons into the graft with either delay. These results demonstrate that a contusion injury site can be manipulated prior to transplantation without causing long-lasting forelimb or hindlimb behavioral deficits and that peripheral nerve grafts support axonal growth after acute or chronic contusion injury.
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Affiliation(s)
- Harra R Sandrow
- Department of Neurobiology and Anatomy, Drexel University College of Medicine, 2900 Queen Lane, Philadelphia, PA 19129, USA
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