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Sample records for non-myelinated schwann cells

  1. The formation of lipid droplets favors intracellular Mycobacterium leprae survival in SW-10, non-myelinating Schwann cells

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    Jin, Song-Hyo; An, Sung-Kwan

    2017-01-01

    Leprosy is a chronic infectious disease that is caused by the obligate intracellular pathogen Mycobacterium leprae (M.leprae), which is the leading cause of all non-traumatic peripheral neuropathies worldwide. Although both myelinating and non-myelinating Schwann cells are infected by M.leprae in patients with lepromatous leprosy, M.leprae preferentially invades the non-myelinating Schwann cells. However, the effect of M.leprae infection on non-myelinating Schwann cells has not been elucidated. Lipid droplets (LDs) are found in M.leprae-infected Schwann cells in the nerve biopsies of lepromatous leprosy patients. M.leprae-induced LD formation favors intracellular M.leprae survival in primary Schwann cells and in a myelinating Schwann cell line referred to as ST88-14. In the current study, we initially characterized SW-10 cells and investigated the effects of LDs on M.leprae-infected SW-10 cells, which are non-myelinating Schwann cells. SW-10 cells express S100, a marker for cells from the neural crest, and NGFR p75, a marker for immature or non-myelinating Schwann cells. SW-10 cells, however, do not express myelin basic protein (MBP), a marker for myelinating Schwann cells, and myelin protein zero (MPZ), a marker for precursor, immature, or myelinating Schwann cells, all of which suggests that SW-10 cells are non-myelinating Schwann cells. In addition, SW-10 cells have phagocytic activity and can be infected with M. leprae. Infection with M. leprae induces the formation of LDs. Furthermore, inhibiting the formation of M. leprae-induced LD enhances the maturation of phagosomes containing live M.leprae and decreases the ATP content in the M. leprae found in SW-10 cells. These facts suggest that LD formation by M. leprae favors intracellular M. leprae survival in SW-10 cells, which leads to the logical conclusion that M.leprae-infected SW-10 cells can be a new model for investigating the interaction of M.leprae with non-myelinating Schwann cells. PMID:28636650

  2. New Insights on Schwann Cell Development

    OpenAIRE

    2015-01-01

    In the peripheral nervous system, Schwann cells are glial cells that are in intimate contact with axons throughout development. Schwann cells generate the insulating myelin sheath and provide vital trophic support to the neurons that they ensheathe. Schwann cell precursors arise from neural crest progenitor cells, and a highly ordered developmental sequence controls the progression of these cells to become mature myelinating or non-myelinating Schwann cells. Here, we discuss both seminal disc...

  3. Biology of Schwann cells.

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    Kidd, Grahame J; Ohno, Nobuhiko; Trapp, Bruce D

    2013-01-01

    The fundamental roles of Schwann cells during peripheral nerve formation and regeneration have been recognized for more than 100 years, but the cellular and molecular mechanisms that integrate Schwann cell and axonal functions continue to be elucidated. Derived from the embryonic neural crest, Schwann cells differentiate into myelinating cells or bundle multiple unmyelinated axons into Remak fibers. Axons dictate which differentiation path Schwann cells follow, and recent studies have established that axonal neuregulin1 signaling via ErbB2/B3 receptors on Schwann cells is essential for Schwann cell myelination. Extracellular matrix production and interactions mediated by specific integrin and dystroglycan complexes are also critical requisites for Schwann cell-axon interactions. Myelination entails expansion and specialization of the Schwann cell plasma membrane over millimeter distances. Many of the myelin-specific proteins have been identified, and transgenic manipulation of myelin genes have provided novel insights into myelin protein function, including maintenance of axonal integrity and survival. Cellular events that facilitate myelination, including microtubule-based protein and mRNA targeting, and actin based locomotion, have also begun to be understood. Arguably, the most remarkable facet of Schwann cell biology, however, is their vigorous response to axonal damage. Degradation of myelin, dedifferentiation, division, production of axonotrophic factors, and remyelination all underpin the substantial regenerative capacity of the Schwann cells and peripheral nerves. Many of these properties are not shared by CNS fibers, which are myelinated by oligodendrocytes. Dissecting the molecular mechanisms responsible for the complex biology of Schwann cells continues to have practical benefits in identifying novel therapeutic targets not only for Schwann cell-specific diseases but other disorders in which axons degenerate. Copyright © 2013 Elsevier B.V. All rights

  4. La célula de Schwann The Schwann Cell

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    Spinel Clara

    2004-12-01

    Full Text Available Las neuronas son las células del sistema nervioso y están recubiertas y protegidas por células gliales. En el sistema nerviosos periférico las células de Schwann (CS son la glía de los nervios. Las prolongaciones o neuritas (axón y dendrita de los cuerpos de las neuronas son recubiertas por las CS y constituyen las fibras nerviosas. La relación íntima entre la CS y la neurita se determina durante el desarrollo embrionario. La CS es esencial en la migración correcta de las neuritas hacia su destino final, pero a su vez las neuritas inducen la maduración de las CS. Esta interacción entre CS y neurita está determinada por factores paracrinos y receptores de membrana de las dos células que interactúan, induciendo la diferenciación de las CS en mielinizadas o no, determinando el número de CS necesarias para cubrir las neuritas, formación adecuada de la vaina de mielina y relación correcta de la CS con la matriz extracelular. De esta manera se forma la fibra nerviosa que culmina inervando o recibiendo estímulos en la periferia del cuerpo. Las CS también son la clave de la regeneración de las neuritas en caso de daño de un nervio periférico.The neurones are the cells of the nervous system and are surrounded and protected by glials cells. In the peripheral nervous system the Schwann cells (SC are the glia of the nerves. The prolongations or neurites (axon and dendrite of the neurones bodies are surrounded by the SC to form nervous fibers. The intimate relationship between the SC and the neurite is determined during embryonic development. The SC is essential for the correct migration of the neurites towards their final destination, but the neurites induce SC maturation as well. This interaction between SC and neurite is determined by paracrine factors and membrane receptors of the two interacting cells, inducing the differentiation of SC in myelinic and non-myelinic, determining the correct number of SC necessary to surround the

  5. New insights on Schwann cell development.

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    Monk, Kelly R; Feltri, M Laura; Taveggia, Carla

    2015-08-01

    In the peripheral nervous system, Schwann cells are glial cells that are in intimate contact with axons throughout development. Schwann cells generate the insulating myelin sheath and provide vital trophic support to the neurons that they ensheathe. Schwann cell precursors arise from neural crest progenitor cells, and a highly ordered developmental sequence controls the progression of these cells to become mature myelinating or nonmyelinating Schwann cells. Here, we discuss both seminal discoveries and recent advances in our understanding of the molecular mechanisms that drive Schwann cell development and myelination with a focus on cell-cell and cell-matrix signaling events.

  6. Liposomes to target peripheral neurons and Schwann cells.

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    Sooyeon Lee

    Full Text Available While a wealth of literature for tissue-specific liposomes is emerging, optimal formulations to target the cells of the peripheral nervous system (PNS are lacking. In this study, we asked whether a novel formulation of phospholipid-based liposomes could be optimized for preferential uptake by microvascular endothelia, peripheral neurons and Schwann cells. Here, we report a unique formulation consisting of a phospholipid, a polymer surfactant and cholesterol that result in enhanced uptake by targeted cells. Using fluorescently labeled liposomes, we followed particle internalization and trafficking through a distinct route from dextran and escape from degradative compartments, such as lysosomes. In cultures of non-myelinating Schwann cells, liposomes associate with the lipid raft marker Cholera toxin, and their internalization is inhibited by disruption of lipid rafts or actin polymerization. In contrast, pharmacological inhibition of clathrin-mediated endocytosis does not significantly impact liposome entry. To evaluate the efficacy of liposome targeting in tissues, we utilized myelinating explant cultures of dorsal root ganglia and isolated diaphragm preparations, both of which contain peripheral neurons and myelinating Schwann cells. In these models, we detected preferential liposome uptake into neurons and glial cells in comparison to surrounding muscle tissue. Furthermore, in vivo liposome administration by intramuscular or intravenous injection confirmed that the particles were delivered to myelinated peripheral nerves. Within the CNS, we detected the liposomes in choroid epithelium, but not in myelinated white matter regions or in brain parenchyma. The described nanoparticles represent a novel neurophilic delivery vehicle for targeting small therapeutic compounds, biological molecules, or imaging reagents into peripheral neurons and Schwann cells, and provide a major advancement toward developing effective therapies for peripheral

  7. Schwann cell hamartoma: case report

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    Bulfamante Gaetano

    2011-06-01

    Full Text Available Abstract Background Colorectal polyps of mesenchymal origin represent a small percentage of gastrointestinal (GI lesions. Nevertheless, they are encountered with increasing frequency since the widespread adoption of colonoscopy screening. Case presentation We report a case of a small colonic polyp that presented as intramucosal diffuse spindle cell proliferation with a benign cytological appearance, strong and diffuse immunoreactivity for S-100 protein, and pure Schwann cell phenotype. Careful morphological, immunohistochemical and clinical evaluation emphasize the differences from other stromal colonic lesions and distinguish it from schwannoma, a circumscribed benign nerve sheath tumor that rarely arises in the GI tract. Conclusion As recently proposed, this lesion was finally described as mucosal Schwann cell hamartoma.

  8. Up-regulation of P2X7 receptors mediating proliferation of Schwann cells after sciatic nerve injury.

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    Song, Xian-min; Xu, Xiao-hui; Zhu, Jiao; Guo, Zhili; Li, Jian; He, Cheng; Burnstock, Geoffrey; Yuan, Hongbin; Xiang, Zhenghua

    2015-06-01

    Peripheral nerve injury (PNI) is a common disease, which results in a partial or total loss of motor, sensory and autonomic functions, leading to a decrease in quality of life. Schwann cells play a vital role in maintaining the peripheral nervous system and in injury and repair. Using immunohistochemistry, Western blot, calcium assay and bromodeoxyuridine (BrdU) proliferation assay, the present study clearly demonstrated that P2X7 receptors (R) were expressed in myelinating and non-myelinating Schwann cells in longitudinal sections of sciatic nerves. After sciatic nerve injury (SNI), P2X7R expression in Schwann cells of injured sciatic nerves was significantly up-regulated during the early days of SNI. Double immunofluorescence of proliferating cell nuclear antigen (PCNA) and P2X7R implied that P2X7R may be involved in proliferation of Schwann cells. Further experiments on primary cultures of Schwann cells showed that P2X7R are functionally expressed in Schwann cells of rat sciatic nerves; ATP via P2X7R can promote Schwann cell proliferation, possibly via the MAPK/ERK intracellular signalling pathway. Other possible roles of P2X7R on Schwann cells are discussed.

  9. Pluripotent Stem Cells for Schwann Cell Engineering

    NARCIS (Netherlands)

    Ma, Ming-San; Boddeke, Erik; Copray, Sjef

    2015-01-01

    Tissue engineering of Schwann cells (SCs) can serve a number of purposes, such as in vitro SC-related disease modeling, treatment of peripheral nerve diseases or peripheral nerve injury, and, potentially, treatment of CNS diseases. SCs can be generated from autologous stem cells in vitro by recapitu

  10. Mechanisms of diabetic neuropathy: Schwann cells.

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    Mizisin, Andrew P

    2014-01-01

    As ensheathing and secretory cells, Schwann cells are a ubiquitous and vital component of the endoneurial microenvironment of peripheral nerves. The interdependence of axons and their ensheathing Schwann cells predisposes each to the impact of injury in the other. Further, the dependence of the blood-nerve interface on trophic support from Schwann cells during development, adulthood, and after injury suggests these glial cells promote the structural and functional integrity of nerve trunks. Here, the developmental origin, injury-induced changes, and mature myelinating and nonmyelinating phenotypes of Schwann cells are reviewed prior to a description of nerve fiber pathology and consideration of pathogenic mechanisms in human and experimental diabetic neuropathy. A fundamental role for aldose-reductase-containing Schwann cells in the pathogenesis of diabetic neuropathy, as well as the interrelationship of pathogenic mechanisms, is indicated by the sensitivity of hyperglycemia-induced biochemical alterations, such as polyol pathway flux, formation of reactive oxygen species, generation of advanced glycosylation end products (AGEs) and deficient neurotrophic support, to blocking polyol pathway flux.

  11. Links between Schwann cells and melanocytes in development and disease.

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    Van Raamsdonk, Catherine D; Deo, Mugdha

    2013-09-01

    Melanocytes are pigment-producing cells that reside in the skin, eyes, ears, heart, and central nervous system meninges of mammals. Schwann cells are glial cells, which closely associate with peripheral nerves, myelinating, and sheathing them. Melanocytes and Schwann cells both arise from the neural crest during development, and some melanocytes arise directly from Schwann cell precursors lining developing spinal nerves. In this review, we explore the connections between melanocytes and Schwann cells in development and transformation.

  12. How Schwann Cells Sort Axons: New Concepts.

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    Feltri, M Laura; Poitelon, Yannick; Previtali, Stefano Carlo

    2016-06-01

    Peripheral nerves contain large myelinated and small unmyelinated (Remak) fibers that perform different functions. The choice to myelinate or not is dictated to Schwann cells by the axon itself, based on the amount of neuregulin I-type III exposed on its membrane. Peripheral axons are more important in determining the final myelination fate than central axons, and the implications for this difference in Schwann cells and oligodendrocytes are discussed. Interestingly, this choice is reversible during pathology, accounting for the remarkable plasticity of Schwann cells, and contributing to the regenerative potential of the peripheral nervous system. Radial sorting is the process by which Schwann cells choose larger axons to myelinate during development. This crucial morphogenetic step is a prerequisite for myelination and for differentiation of Remak fibers, and is arrested in human diseases due to mutations in genes coding for extracellular matrix and linkage molecules. In this review we will summarize progresses made in the last years by a flurry of reverse genetic experiments in mice and fish. This work revealed novel molecules that control radial sorting, and contributed unexpected ideas to our understanding of the cellular and molecular mechanisms that control radial sorting of axons.

  13. Schwann cell myelination requires Dynein function

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    Langworthy Melissa M

    2012-11-01

    Full Text Available Abstract Background Interaction of Schwann cells with axons triggers signal transduction that drives expression of Pou3f1 and Egr2 transcription factors, which in turn promote myelination. Signal transduction appears to be mediated, at least in part, by cyclic adenosine monophosphate (cAMP because elevation of cAMP levels can stimulate myelination in the absence of axon contact. The mechanisms by which the myelinating signal is conveyed remain unclear. Results By analyzing mutations that disrupt myelination in zebrafish, we learned that Dynein cytoplasmic 1 heavy chain 1 (Dync1h1, which functions as a motor for intracellular molecular trafficking, is required for peripheral myelination. In dync1h1 mutants, Schwann cell progenitors migrated to peripheral nerves but then failed to express Pou3f1 and Egr2 or make myelin membrane. Genetic mosaic experiments revealed that robust Myelin Basic Protein expression required Dync1h1 function within both Schwann cells and axons. Finally, treatment of dync1h1 mutants with a drug to elevate cAMP levels stimulated myelin gene expression. Conclusion Dync1h1 is required for retrograde transport in axons and mutations of Dync1h1 have been implicated in axon disease. Our data now provide evidence that Dync1h1 is also required for efficient myelination of peripheral axons by Schwann cells, perhaps by facilitating signal transduction necessary for myelination.

  14. Pluripotent stem cells for Schwann cell engineering.

    Science.gov (United States)

    Ma, Ming-San; Boddeke, Erik; Copray, Sjef

    2015-04-01

    Tissue engineering of Schwann cells (SCs) can serve a number of purposes, such as in vitro SC-related disease modeling, treatment of peripheral nerve diseases or peripheral nerve injury, and, potentially, treatment of CNS diseases. SCs can be generated from autologous stem cells in vitro by recapitulating the various stages of in vivo neural crest formation and SC differentiation. In this review, we survey the cellular and molecular mechanisms underlying these in vivo processes. We then focus on the current in vitro strategies for generating SCs from two sources of pluripotent stem cells, namely embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs). Different methods for SC engineering from ESCs and iPSCs are reviewed and suggestions are proposed for optimizing the existing protocols. Potential safety issues regarding the clinical application of iPSC-derived SCs are discussed as well. Lastly, we will address future aspects of SC engineering.

  15. Schwann cells induce cancer cell dispersion and invasion

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    Deborde, Sylvie; Lyubchik, Anna; Zhou, Yi; He, Shizhi; McNamara, William F.; Chernichenko, Natalya; Lee, Sei-Young; Barajas, Fernando; Chen, Chun-Hao; Bakst, Richard L.; Vakiani, Efsevia; He, Shuangba; Hall, Alan; Wong, Richard J.

    2016-01-01

    Nerves enable cancer progression, as cancers have been shown to extend along nerves through the process of perineural invasion, which carries a poor prognosis. Furthermore, the innervation of some cancers promotes growth and metastases. It remains unclear, however, how nerves mechanistically contribute to cancer progression. Here, we demonstrated that Schwann cells promote cancer invasion through direct cancer cell contact. Histological evaluation of murine and human cancer specimens with perineural invasion uncovered a subpopulation of Schwann cells that associates with cancer cells. Coculture of cancer cells with dorsal root ganglion extracts revealed that Schwann cells direct cancer cells to migrate toward nerves and promote invasion in a contact-dependent manner. Upon contact, Schwann cells induced the formation of cancer cell protrusions in their direction and intercalated between the cancer cells, leading to cancer cell dispersion. The formation of these processes was dependent on Schwann cell expression of neural cell adhesion molecule 1 (NCAM1) and ultimately promoted perineural invasion. Moreover, NCAM1-deficient mice showed decreased neural invasion and less paralysis. Such Schwann cell behavior reflects normal Schwann cell programs that are typically activated in nerve repair but are instead exploited by cancer cells to promote perineural invasion and cancer progression. PMID:26999607

  16. Schwann cells-axon interaction in myelination.

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    Taveggia, Carla

    2016-08-01

    The remarkable interaction between glial cells and axons is crucial for nervous system development and homeostasis. Alterations in this continuous communication can cause severe pathologies that can compromise the integrity of the nervous system. The most dramatic consequence of this interaction is the generation of the myelin sheath, made by myelinating glial cells: Schwann cells in the peripheral nervous system and oligodendrocytes in the central nervous system. In this review I will focus on signals coming from axons in the first part and then on those from Schwann cells that promote the formation and the maintenance of peripheral myelin. I will discuss their inter-relationship together with seminal and important advances recently made.

  17. Electromagnetic induction between axons and their schwann cell myelin-protein sheaths.

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    Goodman, G; Bercovich, D

    2013-12-01

    Two concepts have long dominated vertebrate nerve electrophysiology: (a) Schwann cell-formed myelin sheaths separated by minute non-myelinated nodal gaps and spiraling around axons of peripheral motor nerves reduce current leakage during propagation of trains of axon action potentials; (b) "jumping" by action potentials between successive nodes greatly increases signal conduction velocity. Long-held and more recent assumptions and issues underlying those concepts have been obscured by research emphasis on axon-sheath biochemical symbiosis and nerve regeneration. We hypothesize: mutual electromagnetic induction in the axon-glial sheath association, is fundamental in signal conduction in peripheral and central myelinated axons, explains the g-ratio and is relevant to animal navigation.

  18. Mucosal Schwann cell "Hamartoma": A new entity?

    Institute of Scientific and Technical Information of China (English)

    Paola Pasquini; Andrea Baiocchini; Laura Falasca; Dante Annibali; Guido Gimbo; Francesco Pace; Franca Del Nonno

    2009-01-01

    Schwannoma is a well-described, benign nerve sheath tumor of the soft tissue, but is rare in the gastrointestinal tract. Gastrointestinal schwannomas are often incidentally discovered as small polypoid intraluminal lesions. In this report, we describe the clinicopathologic and immunohistochemical features of a distinctive neural mucosal polyp composed of a diffuse cellular proliferation of uniform bland spindled cells in the lamina propria that entraps the colonic crypts. Immunohistochemical analysis revealed strong and diffuse positivity for the S-100 protein. To avoid confusion of these solitary colorectal polyps containing pure spindled Schwann cell proliferation in the lamina propria with neural lesions that have significant association with inherited syndromes, it is better to use the designation "mucosal Schwann hamartoma".

  19. Chemical Conversion of Human Fibroblasts into Functional Schwann Cells

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    Eva C. Thoma

    2014-10-01

    Full Text Available Direct transdifferentiation of somatic cells is a promising approach to obtain patient-specific cells for numerous applications. However, conversion across germ-layer borders often requires ectopic gene expression with unpredictable side effects. Here, we present a gene-free approach that allows efficient conversion of human fibroblasts via a transient progenitor stage into Schwann cells, the major glial cell type of peripheral nerves. Using a multikinase inhibitor, we transdifferentiated fibroblasts into transient neural precursors that were subsequently further differentiated into Schwann cells. The resulting induced Schwann cells (iSCs expressed numerous Schwann cell-specific proteins and displayed neurosupportive and myelination capacity in vitro. Thus, we established a strategy to obtain mature Schwann cells from human postnatal fibroblasts under chemically defined conditions without the introduction of ectopic genes.

  20. Immortalization of human normal and NF1 neurofibroma Schwann cells.

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    Li, Hua; Chang, Lung-Ji; Neubauer, Debbie R; Muir, David F; Wallace, Margaret R

    2016-10-01

    Neurofibromas, which are benign Schwann cell tumors, are the hallmark feature in the autosomal dominant condition neurofibromatosis 1 (NF1) and are associated with biallelic loss of NF1 gene function. There is a need for effective therapies for neurofibromas, particularly the larger, plexiform neurofibromas. Tissue culture is an important tool for research. However, it is difficult to derive enriched human Schwann cell cultures, and most enter replicative senescence after 6-10 passages, impeding cell-based research in NF1. Through exogenous expression of human telomerase reverse transcriptase and murine cyclin-dependent kinase (mCdk4), normal (NF1 wild-type), neurofibroma-derived Schwann cells heterozygous for NF1 mutation, and neurofibroma-derived Schwann cells homozygous for NF1 mutation were immortalized, including some matched samples from the same NF1 patient. Initial experiments employed retroviral vectors, while subsequent work utilized lentiviral vectors carrying these genes because of improved efficiency. Expression of both transgenes was required for immortalization. Molecular and immunohistochemical analysis indicated that these cell lines are of Schwann cell lineage and have a range of phenotypes, many of which are consistent with their primary cultures. This is the first report of immortalization and detailed characterization of multiple human NF1 normal nerve and neurofibroma-derived Schwann cell lines, which will be highly useful research tools to study NF1 and other Schwann tumor biology and conditions.

  1. Laminin is required for Schwann cell morphogenesis.

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    Yu, Wei-Ming; Chen, Zu-Lin; North, Alison J; Strickland, Sidney

    2009-04-01

    Development of the peripheral nervous system requires radial axonal sorting by Schwann cells (SCs). To accomplish sorting, SCs must both proliferate and undergo morphogenetic changes such as process extension. Signaling studies reveal pathways that control either proliferation or morphogenesis, and laminin is essential for SC proliferation. However, it is not clear whether laminin is also required for SC morphogenesis. By using a novel time-lapse live-cell-imaging technique, we demonstrated that laminins are required for SCs to form a bipolar shape as well as for process extension. These morphological deficits are accompanied by alterations in signaling pathways. Phosphorylation of Schwannomin at serine 518 and activation of Rho GTPase Cdc42 and Rac1 were all significantly decreased in SCs lacking laminins. Inhibiting Rac1 and/or Cdc42 activities in cultured SCs attenuated laminin-induced myelination, whereas forced activation of Rac1 and/or Cdc42 in vivo improved sorting and hypomyelinating phenotypes in SCs lacking laminins. These findings indicate that laminins play a pivotal role in regulating SC cytoskeletal signaling. Coupled with previous results demonstrating that laminin is critical for SC proliferation, this work identifies laminin signaling as a central regulator coordinating the processes of proliferation and morphogenesis in radial axonal sorting.

  2. Schwann cells for spinal cord repair

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    Oudega M.

    2005-01-01

    Full Text Available The complex nature of spinal cord injury appears to demand a multifactorial repair strategy. One of the components that will likely be included is an implant that will fill the area of lost nervous tissue and provide a growth substrate for injured axons. Here we will discuss the role of Schwann cells (SCs in cell-based, surgical repair strategies of the injured adult spinal cord. We will review key studies that showed that intraspinal SC grafts limit injury-induced tissue loss and promote axonal regeneration and myelination, and that this response can be improved by adding neurotrophic factors or anti-inflammatory agents. These results will be compared with several other approaches to the repair of the spinal cord. A general concern with repair strategies is the limited functional recovery, which is in large part due to the failure of axons to grow across the scar tissue at the distal graft-spinal cord interface. Consequently, new synaptic connections with spinal neurons involved in motor function are not formed. We will highlight repair approaches that did result in growth across the scar and discuss the necessity for more studies involving larger, clinically relevant types of injuries, addressing this specific issue. Finally, this review will reflect on the prospect of SCs for repair strategies in the clinic.

  3. TACE (ADAM17) inhibits Schwann cell myelination.

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    La Marca, Rosa; Cerri, Federica; Horiuchi, Keisuke; Bachi, Angela; Feltri, M Laura; Wrabetz, Lawrence; Blobel, Carl P; Quattrini, Angelo; Salzer, James L; Taveggia, Carla

    2011-06-12

    Tumor necrosis factor-α-converting enzyme (TACE; also known as ADAM17) is a proteolytic sheddase that is responsible for the cleavage of several membrane-bound molecules. We report that TACE cleaves neuregulin-1 (NRG1) type III in the epidermal growth factor domain, probably inactivating it (as assessed by deficient activation of the phosphatidylinositol-3-OH kinase pathway), and thereby negatively regulating peripheral nervous system (PNS) myelination. Lentivirus-mediated knockdown of TACE in vitro in dorsal root ganglia neurons accelerates the onset of myelination and results in hypermyelination. In agreement, motor neurons of conditional knockout mice lacking TACE specifically in these cells are significantly hypermyelinated, and small-caliber fibers are aberrantly myelinated. Further, reduced TACE activity rescues hypomyelination in NRG1 type III haploinsufficient mice in vivo. We also show that the inhibitory effect of TACE is neuron-autonomous, as Schwann cells lacking TACE elaborate myelin of normal thickness. Thus, TACE is a modulator of NRG1 type III activity and is a negative regulator of myelination in the PNS.

  4. Transcriptional regulation induced by cAMP elevation in mouse Schwann cells

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    Daniela Schmid

    2014-04-01

    Full Text Available In peripheral nerves, Schwann cell development is regulated by a variety of signals. Some of the aspects of Schwann cell differentiation can be reproduced in vitro in response to forskolin, an adenylyl cyclase activator elevating intracellular cAMP levels. Herein, the effect of forskolin treatment was investigated by a comprehensive genome-wide expression study on primary mouse Schwann cell cultures. Additional to myelin-related genes, many so far unconsidered genes were ascertained to be modulated by forskolin. One of the strongest differentially regulated gene transcripts was the transcription factor Olig1 (oligodendrocyte transcription factor 1, whose mRNA expression levels were reduced in treated Schwann cells. Olig1 protein was localized in myelinating and nonmyelinating Schwann cells within the sciatic nerve as well as in primary Schwann cells, proposing it as a novel transcription factor of the Schwann cell lineage. Data analysis further revealed that a number of differentially expressed genes in forskolin-treated Schwann cells were associated with the ECM (extracellular matrix, underlining its importance during Schwann cell differentiation in vitro. Comparison of samples derived from postnatal sciatic nerves and from both treated and untreated Schwann cell cultures showed considerable differences in gene expression between in vivo and in vitro, allowing us to separate Schwann cell autonomous from tissue-related changes. The whole data set of the cell culture microarray study is provided to offer an interactive search tool for genes of interest.

  5. Transcriptional Regulation Induced by cAMP Elevation in Mouse Schwann Cells

    Directory of Open Access Journals (Sweden)

    Daniela Schmid

    2014-03-01

    Full Text Available In peripheral nerves, Schwann cell development is regulated by a variety of signals. Some of the aspects of Schwann cell differentiation can be reproduced in vitro in response to forskolin, an adenylyl cyclase activator elevating intracellular cAMP levels. Herein, the effect of forskolin treatment was investigated by a comprehensive genome-wide expression study on primary mouse Schwann cell cultures. Additional to myelin-related genes, many so far unconsidered genes were ascertained to be modulated by forskolin. One of the strongest differentially regulated gene transcripts was the transcription factor Olig1 (oligodendrocyte transcription factor 1, whose mRNA expression levels were reduced in treated Schwann cells. Olig1 protein was localized in myelinating and nonmyelinating Schwann cells within the sciatic nerve as well as in primary Schwann cells, proposing it as a novel transcription factor of the Schwann cell lineage. Data analysis further revealed that a number of differentially expressed genes in forskolin-treated Schwann cells were associated with the ECM (extracellular matrix, underlining its importance during Schwann cell differentiation in vitro. Comparison of samples derived from postnatal sciatic nerves and from both treated and untreated Schwann cell cultures showed considerable differences in gene expression between in vivo and in vitro, allowing us to separate Schwann cell autonomous from tissue-related changes. The whole data set of the cell culture microarray study is provided to offer an interactive search tool for genes of interest.

  6. Edaravone combined with Schwann cell transplantation may repair spinal cord injury in rats

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    Shu-quan Zhang

    2015-01-01

    Full Text Available Edaravone has been shown to delay neuronal apoptosis, thereby improving nerve function and the microenvironment after spinal cord injury. Edaravone can provide a favorable environment for the treatment of spinal cord injury using Schwann cell transplantation. This study used rat models of complete spinal cord transection at T 9. Six hours later, Schwann cells were transplanted in the head and tail ends of the injury site. Simultaneously, edaravone was injected through the caudal vein. Eight weeks later, the PKH-26-labeled Schwann cells had survived and migrated to the center of the spinal cord injury region in rats after combined treatment with edaravone and Schwann cells. Moreover, the number of PKH-26-labeled Schwann cells in the rat spinal cord was more than that in rats undergoing Schwann cell transplantation alone or rats without any treatment. Horseradish peroxidase retrograde tracing revealed that the number of horseradish peroxidase-positive nerve fibers was greater in rats treated with edaravone combined withSchwann cells than in rats with Schwann cell transplantation alone. The results demonstrated that lower extremity motor function and neurophysiological function were better in rats treated with edaravone and Schwann cells than in rats with Schwann cell transplantation only. These data confirmed that Schwann cell transplantation combined with edaravone injection promoted the regeneration of nerve fibers of rats with spinal cord injury and improved neurological function.

  7. Schwann cells: a new player in the tumor microenvironment.

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    Bunimovich, Yuri L; Keskinov, Anton A; Shurin, Galina V; Shurin, Michael R

    2017-08-01

    Cancerous cells must cooperate with the surrounding stroma and non-malignant cells within the microenvironment to support the growth and invasion of the tumor. The nervous system is a component of every organ system of the body, and therefore, is invariably at the front line of the tumor invasion. Due to the complexity of the nervous system physiology, this review separately discusses the contributions of the central and peripheral nervous systems to the tumorigenesis and tumor progression. We further focus the discussion on the evidence that Schwann cells aid in tumor growth and invasion. Schwann cells, a largely unexplored element of the tumor microenvironment, may participate in the creation of tumor-favorable conditions through both bi-directional interaction with cancer cells and the facilitation of the immune-suppressive microenvironment through the mechanism of neural repair and immunomodulation.

  8. Schwann cells originating from skin-derived precursors promote peripheral nerve regeneration in rats

    Institute of Scientific and Technical Information of China (English)

    Ping Zhang; Xiaocheng Lu; Jianghai Chen; Zhenbing Chen

    2014-01-01

    Artiifcial guidance channels containing Schwann cells can promote the regeneration of injured peripheral nerve over long distances. However, primary Schwann cells are not suitable for autotransplantation. Under speciifc conditions, skin-derived progenitors can be induced to dif-ferentiate into Schwann cells. Therefore, adult rat dorsal skin (dermis)-derived progenitors were isolated and induced to differentiate with DMEM/F12 containing B27, neuregulin 1, and for-skolin. Immunolfuorescence staining and reverse transcription polymerase chain reaction (RT-PCR) conifrmed that the resultant cells were indeed Schwann cells. Artiifcial guidance channels containing skin-derived progenitors, Schwann cells originating from skin-derived progenitors, or primary Schwann cells were used to bridge 5 mm sciatic nerve defects. Schwann cells originating from skin-derived progenitors signiifcantly promoted sciatic nerve axonal regeneration. The sig-niifcant recovery of injured rat sciatic nerve function after the transplantation of Schwann cells originating from skin-derived progenitors was conifrmed by electromyogram. The therapeutic effect of Schwann cells originating from skin-derived progenitors was better than that of skin-de-rived progenitors. These findings indicate that Schwann cells originating from skin-derived precursors can promote peripheral nerve regeneration in rats.

  9. A Role for Neuropilins in the Interaction between Schwann Cells and Meningeal Cells

    NARCIS (Netherlands)

    Roet, Kasper C D; Wirz, Kerstin T S; Franssen, Elske H P; Verhaagen, J.

    2014-01-01

    In their natural habitat, the peripheral nerve, Schwann cells (SCs) form nicely aligned pathways (also known as the bands of Büngner) that guide regenerating axons to their targets. Schwann cells that are implanted in the lesioned spinal cord fail to align in pathways that could support axon growth

  10. Blocking mitochondrial calcium release in Schwann cells prevents demyelinating neuropathies.

    Science.gov (United States)

    Gonzalez, Sergio; Berthelot, Jade; Jiner, Jennifer; Perrin-Tricaud, Claire; Fernando, Ruani; Chrast, Roman; Lenaers, Guy; Tricaud, Nicolas

    2016-03-01

    Schwann cells produce myelin sheath around peripheral nerve axons. Myelination is critical for rapid propagation of action potentials, as illustrated by the large number of acquired and hereditary peripheral neuropathies, such as diabetic neuropathy or Charcot-Marie-Tooth diseases, that are commonly associated with a process of demyelination. However, the early molecular events that trigger the demyelination program in these diseases remain unknown. Here, we used virally delivered fluorescent probes and in vivo time-lapse imaging in a mouse model of demyelination to investigate the underlying mechanisms of the demyelination process. We demonstrated that mitochondrial calcium released by voltage-dependent anion channel 1 (VDAC1) after sciatic nerve injury triggers Schwann cell demyelination via ERK1/2, p38, JNK, and c-JUN activation. In diabetic mice, VDAC1 activity was altered, resulting in a mitochondrial calcium leak in Schwann cell cytoplasm, thereby priming the cell for demyelination. Moreover, reduction of mitochondrial calcium release, either by shRNA-mediated VDAC1 silencing or pharmacological inhibition, prevented demyelination, leading to nerve conduction and neuromuscular performance recovery in rodent models of diabetic neuropathy and Charcot-Marie-Tooth diseases. Therefore, this study identifies mitochondria as the early key factor in the molecular mechanism of peripheral demyelination and opens a potential opportunity for the treatment of demyelinating peripheral neuropathies.

  11. Rapamycin promotes Schwann cell migration and nerve growth factor secretion

    OpenAIRE

    Liu, Fang; Zhang, Haiwei; Zhang, Kaiming; Wang, Xinyu; Li, Shipu; Yin, Yixia

    2014-01-01

    Rapamycin, similar to FK506, can promote neural regeneration in vitro. We assumed that the mechanisms of action of rapamycin and FK506 in promoting peripheral nerve regeneration were similar. This study compared the effects of different concentrations of rapamycin and FK506 on Schwann cells and investigated effects and mechanisms of rapamycin on improving peripheral nerve regeneration. Results demonstrated that the lowest rapamycin concentration (1.53 nmol/L) more significantly promoted Schwa...

  12. Dynamic regulation of Schwann cell enhancers after peripheral nerve injury.

    Science.gov (United States)

    Hung, Holly A; Sun, Guannan; Keles, Sunduz; Svaren, John

    2015-03-13

    Myelination of the peripheral nervous system is required for axonal function and long term stability. After peripheral nerve injury, Schwann cells transition from axon myelination to a demyelinated state that supports neuronal survival and ultimately remyelination of axons. Reprogramming of gene expression patterns during development and injury responses is shaped by the actions of distal regulatory elements that integrate the actions of multiple transcription factors. We used ChIP-seq to measure changes in histone H3K27 acetylation, a mark of active enhancers, to identify enhancers in myelinating rat peripheral nerve and their dynamics after demyelinating nerve injury. Analysis of injury-induced enhancers identified enriched motifs for c-Jun, a transcription factor required for Schwann cells to support nerve regeneration. We identify a c-Jun-bound enhancer in the gene for Runx2, a transcription factor induced after nerve injury, and we show that Runx2 is required for activation of other induced genes. In contrast, enhancers that lose H3K27ac after nerve injury are enriched for binding sites of the Sox10 and early growth response 2 (Egr2/Krox20) transcription factors, which are critical determinants of Schwann cell differentiation. Egr2 expression is lost after nerve injury, and many Egr2-binding sites lose H3K27ac after nerve injury. However, the majority of Egr2-bound enhancers retain H3K27ac, indicating that other transcription factors maintain active enhancer status after nerve injury. The global epigenomic changes in H3K27ac deposition pinpoint dynamic changes in enhancers that mediate the effects of transcription factors that control Schwann cell myelination and peripheral nervous system responses to nerve injury.

  13. Nanoparticles carrying neurotrophin-3-modified Schwann cells promote repair of sciatic nerve defects

    Institute of Scientific and Technical Information of China (English)

    Haibin Zong; Hongxing Zhao; Yilei Zhao; Jingling Jia; Libin Yang; Chao Ma; Yang Zhang; Yuzhen Dong

    2013-01-01

    Schwann cells and neurotrophin-3 play an important role in neural regeneration, but the secretion of neurotrophin-3 from Schwann cells is limited, and exogenous neurotrophin-3 is inactived easily in vivo. In this study, we have transfected neurotrophin-3 into Schwann cells cultured in vitro using nanoparticle liposomes. Results showed that neurotrophin-3 was successfully transfected into Schwann cells, where it was expressed effectively and steadily. A composite of Schwann cells transfected with neurotrophin-3 and poly(lactic-co-glycolic acid) biodegradable conduits was transplanted into rats to repair 10-mm sciatic nerve defects. Transplantation of the composite scaffold could restore the myoelectricity and wave amplitude of the sciatic nerve by electrophysiological examination, promote nerve axonal and myelin regeneration, and delay apoptosis of spinal motor neurons. Experimental findings indicate that neurotrophin-3 transfected Schwann cells combined with bridge grafting can promote neural regeneration and functional recovery after nerve injury.

  14. ProBDNF inhibits collective migration and chemotaxis of rat Schwann cells.

    Science.gov (United States)

    Ding, You-Quan; Li, Xuan-Yang; Xia, Guan-Nan; Ren, Hong-Yi; Zhou, Xin-Fu; Su, Bing-Yin; Qi, Jian-Guo

    2016-10-01

    Schwann cell migration, including collective migration and chemotaxis, is essential for the formation of coordinate interactions between Schwann cells and axons during peripheral nerve development and regeneration. Moreover, limited migration of Schwann cells imposed a serious obstacle on Schwann cell-astrocytes intermingling and spinal cord repair after Schwann cell transplantation into injured spinal cords. Recent studies have shown that mature brain-derived neurotrophic factor, a member of the neurotrophin family, inhibits Schwann cell migration. The precursor form of brain-derived neurotrophic factor, proBDNF, was expressed in the developing or degenerating peripheral nerves and the injured spinal cords. Since "the yin and yang of neurotrophin action" has been established as a common sense, proBDNF would be expected to promote Schwann cell migration. However, we found, in the present study, that exogenous proBDNF also inhibited in vitro collective migration and chemotaxis of RSC 96 cells, a spontaneously immortalized rat Schwann cell line. Moreover, proBDNF suppressed adhesion and spreading of those cells. At molecular level, proBDNF inhibits F-actin polymerization and focal adhesion dynamics in cultured RSC 96 cells. Therefore, our results suggested a special case against the classical opinion of "the yin and yang of neurotrophin action" and implied that proBDNF might modulate peripheral nerve development or regeneration and spinal cord repair through perturbing native or transplanted Schwann cell migration.

  15. Arrest of Myelination and Reduced Axon Growth when Schwann Cells Lack mTOR

    OpenAIRE

    Sherman, Diane L; Krols, Michiel; Wu, Lai-Man N; Grove, Matthew; Nave, Klaus-Armin; Gangloff, Yann-Gaël; Brophy, Peter J.

    2012-01-01

    In developing peripheral nerves differentiating Schwann cells sort individual axons from bundles and ensheath them to generate multiple layers of myelin. In recent years there has been an increasing understanding of the extracellular and intracellular factors that initiate and stimulate Schwann cell myelination together with a growing appreciation of some of the signalling pathways involved. However, our knowledge of how Schwann cell growth is regulated during myelination is still incomplete....

  16. Extracellular ATP inhibits Schwann cell dedifferentiation and proliferation in an ex vivo model of Wallerian degeneration

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Youn Ho; Lee, Seo Jin [Department of Anatomy, College of Medicine, Kyung Hee University, Heogi-Dong 1, Dongdaemun-Gu, Seoul 130-701 (Korea, Republic of); Jung, Junyang, E-mail: jjung@khu.ac.kr [Department of Anatomy, College of Medicine, Kyung Hee University, Heogi-Dong 1, Dongdaemun-Gu, Seoul 130-701 (Korea, Republic of)

    2013-01-11

    Highlights: Black-Right-Pointing-Pointer ATP-treated sciatic explants shows the decreased expression of p75NGFR. Black-Right-Pointing-Pointer Extracellular ATP inhibits the expression of phospho-ERK1/2. Black-Right-Pointing-Pointer Lysosomal exocytosis is involved in Schwann cell dedifferentiation. Black-Right-Pointing-Pointer Extracellular ATP blocks Schwann cell proliferation in sciatic explants. -- Abstract: After nerve injury, Schwann cells proliferate and revert to a phenotype that supports nerve regeneration. This phenotype-changing process can be viewed as Schwann cell dedifferentiation. Here, we investigated the role of extracellular ATP in Schwann cell dedifferentiation and proliferation during Wallerian degeneration. Using several markers of Schwann cell dedifferentiation and proliferation in sciatic explants, we found that extracellular ATP inhibits Schwann cell dedifferentiation and proliferation during Wallerian degeneration. Furthermore, the blockage of lysosomal exocytosis in ATP-treated sciatic explants is sufficient to induce Schwann cell dedifferentiation. Together, these findings suggest that ATP-induced lysosomal exocytosis may be involved in Schwann cell dedifferentiation.

  17. Schwann cells express erythropoietin receptor and represent a major target for Epo in peripheral nerve injury.

    Science.gov (United States)

    Li, Xiaoqing; Gonias, Steven L; Campana, W Marie

    2005-09-01

    Erythropoietin (Epo) expresses potent neuroprotective activity in the peripheral nervous system; however, the underlying mechanism remains incompletely understood. In this study, we demonstrate that Epo is upregulated in sciatic nerve after chronic constriction injury (CCI) and crush injury in rats, largely due to local Schwann cell production. In uninjured and injured nerves, Schwann cells also express Epo receptor (EpoR), and its expression is increased during Wallerian degeneration. CCI increased the number of Schwann cells at the injury site and the number was further increased by exogenously administered recombinant human Epo (rhEpo). To explore the activity of Epo in Schwann cells, primary cultures were established. These cells expressed cell-surface Epo receptors, with masses of 71 and 62 kDa, as determined by surface protein biotinylation and affinity precipitation. The 71-kDa species was rapidly but transiently tyrosine-phosphorylated in response to rhEpo. ERK/MAP kinase was also activated in rhEpo-treated Schwann cells; this response was blocked by pharmacologic antagonism of JAK-2. RhEpo promoted Schwann cell proliferation, as determined by BrdU incorporation. Cell proliferation was ERK/MAP kinase-dependent. These results support a model in which Schwann cells are a major target for Epo in injured peripheral nerves, perhaps within the context of an autocrine signaling pathway. EpoR-induced cell signaling and Schwann cell proliferation may protect injured peripheral nerves and promote regeneration.

  18. Schwann cell myelination requires integration of laminin activities.

    Science.gov (United States)

    McKee, Karen K; Yang, Dong-Hua; Patel, Rajesh; Chen, Zu-Lin; Strickland, Sidney; Takagi, Junichi; Sekiguchi, Kiyotoshi; Yurchenco, Peter D

    2012-10-01

    Laminins promote early stages of peripheral nerve myelination by assembling basement membranes (BMs) on Schwann cell surfaces, leading to activation of β1 integrins and other receptors. The BM composition, structural bonds and ligands needed to mediate this process, however, are not well understood. Mice hypomorphic for laminin γ1-subunit expression that assembled endoneurial BMs with reduced component density exhibited an axonal sorting defect with amyelination but normal Schwann cell proliferation, the latter unlike the null. To identify the basis for this, and to dissect participating laminin interactions, LAMC1 gene-inactivated dorsal root ganglia were treated with recombinant laminin-211 and -111 lacking different architecture-forming and receptor-binding activities, to induce myelination. Myelin-wrapping of axons by Schwann cells was found to require higher laminin concentrations than either proliferation or axonal ensheathment. Laminins that were unable to polymerize through deletions that removed critical N-terminal (LN) domains, or that lacked cell-adhesive globular (LG) domains, caused reduced BMs and almost no myelination. Laminins engineered to bind weakly to α6β1 and/or α7β1 integrins through their LG domains, even though they could effectively assemble BMs, decreased myelination. Proliferation depended upon both integrin binding to LG domains and polymerization. Collectively these findings reveal that laminins integrate scaffold-forming and cell-adhesion activities to assemble an endoneurial BM, with myelination and proliferation requiring additional α6β1/α7β1-laminin LG domain interactions, and that a high BM ligand/structural density is needed for efficient myelination.

  19. Alginic acid sodium hydrogel co-transplantation with Schwann cells for rat spinal cord repair.

    Science.gov (United States)

    Wang, Haibao; Liu, Chibo; Ma, Xueqiang

    2012-07-04

    The aim of the study was investigating the influence of Schwann cells-alginic acid sodium hydrogel co-transplantation on a rat model of spinal cord injury. Sprague-Dawley (SD) rats were randomly assigned to 4 groups: control, injury, injury with Schwann cell transplantation, and injury with Schwann cells-alginic acid sodium hydrogel co-transplantation. Gelatin sponge blocks containing a Schwann cell suspension were transplanted into the injury site in the Schwann cell group; Schwann cells seeded in alginic acid sodium hydrogel were transplanted into the injury site in the Schwann cells-alginic acid sodium hydrogel group. At 12 h, 1, 3, 7, and 21 days after surgery, animals were assessed on the Basso, Beattie and Bresnahan (BBB) locomotor rating scale and then were sacrificed. In the injury group, Bcl-2 immunoreactive cells peaked at 3 days after surgery, and the expression level returned to normal level at 14 days. In the co-transplantation group, Bcl-2 immunoreactive cells in the spinal cord-transected segments were significantly increased until 7 days (p alginic acid sodium hydrogel transplantation group than in the simple injury and Schwann cell groups (p alginic acid sodium hydrogel co-transplantation could inhibit cellular apoptosis and enhance Bcl-2 expression in the spinal cord-transected segments, and thereby promote the recovery of locomotor function after spinal cord injury, although it did not reach full rehabilitation.

  20. Role of endogenous Schwann cells in tissue repair after spinal cord injury

    Institute of Scientific and Technical Information of China (English)

    Shu-xin Zhang; Fengfa Huang; Mary Gates; Eric G. Holmberg

    2013-01-01

    Schwann cells are glial cells of peripheral nervous system, responsible for axonal myelination and ensheathing, as well as tissue repair following a peripheral nervous system injury. They are one of several cell types that are widely studied and most commonly used for cell transplantation to treat spinal cord injury, due to their intrinsic characteristics including the ability to secrete a variety of neurotrophic factors. This mini review summarizes the recent findings of endogenous Schwann cells after spinal cord injury and discusses their role in tissue repair and axonal regeneration. After spinal cord injury, numerous endogenous Schwann cells migrate into the lesion site from the nerve roots, involving in the construction of newly formed repaired tissue and axonal myelination. These invading Schwann cells also can move a long distance away from the injury site both rostrally and caudally. In addition, Schwann cells can be induced to migrate by minimal insults (such as scar ablation) within the spinal cord and integrate with astrocytes under certain circumstances. More importantly, the host Schwann cells can be induced to migrate into spinal cord by transplantation of different cell types, such as exogenous Schwann cells, olfactory ensheathing cells, and bone marrow-derived stromal stem cells. Migration of endogenous Schwann cells following spinal cord injury is a common natural phenomenon found both in animal and human, and the myelination by Schwann cells has been examined effective in signal conduction electrophysiologically. Therefore, if the inherent properties of endogenous Schwann cells could be developed and utilized, it would offer a new avenue for the restoration of injured spinal cord.

  1. SOX10 transactivates S100B to suppress Schwann cell proliferation and to promote myelination.

    Directory of Open Access Journals (Sweden)

    Sayaka Fujiwara

    Full Text Available Schwann cells are an important cell source for regenerative therapy for neural disorders. We investigated the role of the transcription factor sex determining region Y (SRY-box 10 (SOX10 in the proliferation and myelination of Schwann cells. SOX10 is predominantly expressed in rat sciatic nerve-derived Schwann cells and is induced shortly after birth. Among transcription factors known to be important for the differentiation of Schwann cells, SOX10 potently transactivates the S100B promoter. In cultures of Schwann cells, overexpressing SOX10 dramatically induces S100B expression, while knocking down SOX10 with shRNA suppresses S100B expression. Here, we identify three core response elements of SOX10 in the S100B promoter and intron 1 with a putative SOX motif. Knockdown of either SOX10 or S100B enhances the proliferation of Schwann cells. In addition, using dissociated cultures of dorsal root ganglia, we demonstrate that suppressing S100B with shRNA impairs myelination of Schwann cells. These results suggest that the SOX10-S100B signaling axis critically regulates Schwann cell proliferation and myelination, and therefore is a putative therapeutic target for neuronal disorders.

  2. Effect of Rat Schwann Cell Secretion on Proliferation and Differentiation of Human Neural Stem Cells

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Objective To investigate the effect of rat Schwann cell secretion on the proliferation and differentiation of human embryonic neural stem cells (NSCs). Methods The samples were divided into three groups. In Group One, NSCs were cultured in DMED/F12 in which Schwann cells had grown for one day. In Group Two, NSCs and Schwann cells were co-cultured. In Group Three, NSCs were cultured in DMEM/F12. The morphology of NSCs was checked and b-tubulin, GalC, hoechst 33342 and GFAP labellings were detected. Results In Group One, all neural spheres were attached to the bottom and differentiated. The majority of them were b-tubulin positive while a few of cells were GFAP or GalC positive. In Group Two, neural spheres remained undifferentiatied and their proliferation was inhibited in places where Schwann cells were robust. In places where there were few Schwann cells, NSCs performed in a similar manner as in Group One. In Group Three, the cell growth state deteriorated day after day. On the 7th day, most NSCs died. Conclusion The secretion of rat Schwann cells has a growth supportive and differentiation-inducing effect on human NSCs.

  3. Nerve Injury-Induced c-Jun Activation in Schwann Cells Is JNK Independent

    Directory of Open Access Journals (Sweden)

    Charlotta Lindwall Blom

    2014-01-01

    Full Text Available We investigated (a if activation of the mitogen activated protein kinase (MAPK pathway was linked to the stress activated protein kinase (SAPK pathway and (b if JNK was required for activation of c-Jun in Schwann cells of rat sciatic nerve following injury. To this aim, ERK1/2 and the transcription factors c-Jun and ATF-3 were studied by immunohistochemistry in segments of transected nerves. We utilized pharmacological inhibitors of both signal transduction pathways in vitro to determine the effects on downstream signalling events, such as c-Jun activation, and on Schwann cell survival and proliferation. A transection induces c-Jun and ATF-3 transcription in Schwann cells. These events are followed by Schwann cell activation of c-Jun in the injured nerve. The MAPK inhibitor U0126 blocked ERK1/2 activation and reduced Schwann cell proliferation as well as induction of c-Jun transcription. The JNK inhibitor SP600125 reduced Schwann cell proliferation, but did not affect the expression of ERK1/2 or injury-induced increases in c-Jun or ATF-3 levels. Importantly, nerve injury induces Schwann cell activation of c-Jun by phosphorylation, which, in contrast to in sensory neurons, is JNK independent. MAP kinases, other than JNK, can potentially activate c-Jun in Schwann cells following injury; information that is crucial to create new nerve reconstruction strategies.

  4. YAP and TAZ control peripheral myelination and the expression of laminin receptors in Schwann cells

    Science.gov (United States)

    Poitelon, Y; Lopez-Anido, C; Catignas, K; Berti, C; Palmisano, M; Williamson, C; Ameroso, D; Abiko, K; Hwang, Y; Gregorieff, A; Wrana, J; Asmani, M; Zhao, R; Sim, FJ; Wrabetz, L; Svaren, J; Feltri, ML

    2016-01-01

    Myelination is essential for nervous system function. Schwann cells interact with neurons and the basal lamina to myelinate axons, using known receptors, signals and transcription factors. In contrast, the transcriptional control of axonal sorting and the role of mechanotransduction in myelination are largely unknown. Yap and Taz are effectors of the Hippo pathway that integrate chemical and mechanical signals in cells. We describe a previously unknown role for the Hippo pathway in myelination. Using conditional mutagenesis in mice we show that Taz is required in Schwann cells for radial sorting and myelination, and that Yap is redundant with Taz. Yap/Taz are activated in Schwann cells by mechanical stimuli, and regulate Schwann cell proliferation and transcription of basal lamina receptor genes, both necessary for proper radial sorting of axons and subsequent myelination. These data link transcriptional effectors of the Hippo pathway and of mechanotransduction to myelin formation in Schwann cells. PMID:27273766

  5. Laminins and their receptors in Schwann cells and hereditary neuropathies.

    Science.gov (United States)

    Feltri, Maria Laura; Wrabetz, Lawrence

    2005-06-01

    This review focuses on the influence of laminins, mediated through laminin receptors present on Schwann cells, on peripheral nerve development and pathology. Laminins influence multiple aspects of cell differentiation and tissue morphogenesis, including cell survival, proliferation, cytoskeletal rearrangements, and polarity. Peripheral nerves are no exception, as shown by the discovery that defective laminin signals contribute to the pathogenesis of diverse neuropathies such as merosin-deficient congenital muscular dystrophy and Charcot-Marie-Tooth 4F, neurofibromatosis, and leprosy. In the last 5 years, advanced molecular and cell biological techniques and conditional mutagenesis in mice began revealing the role of different laminins and receptors in developing nerves. In this way, we are starting to explain morphological and pathological observations beginning at the start of the last century. Here, we review these recent advances and show how the roles of laminins and their receptors are surprisingly varied in both time and place.

  6. Axonal and Schwann cell BACE1 is equally required for remyelination of peripheral nerves.

    Science.gov (United States)

    Hu, Xiangyou; Hu, Jinxuan; Dai, Lu; Trapp, Bruce; Yan, Riqiang

    2015-03-04

    Inhibition of β-site APP cleaving enzyme 1 (BACE1) is being pursued as a therapeutic target for treating patients with Alzheimer's disease because BACE1 is the sole β-secretase for generating β-amyloid peptide. Knowledge regarding the other cellular functions of BACE1 is therefore critical for the safe use of BACE1 inhibitors in human patients. BACE1 deficiency in mice causes hypomyelination during development and impairs remyelination in injured sciatic nerves. Since BACE1 is expected to be ubiquitously expressed, we asked whether axonal or Schwann cell BACE1 is required for optimal remyelination. By swapping sciatic nerve segments from BACE1-null mice with the corresponding wild-type nerve segments or vice versa, we tested how a deficiency of BACE1 in Schwann cells or axons affects remyelination. Our results show that BACE1 in axons and Schwann cells is similarly important for remyelination of regenerated axons. Nerve injury induces BACE1 transcription and protein levels are elevated in Schwann cells. Expression of type I neuregulin 1 (Nrg1), rather than type III Nrg1, was induced by Schwann cells, and the abolished Nrg1 cleavage in BACE1-null Schwann cells contributed to decreased remyelination of regenerated axons. Hence, this study is the first to demonstrate the equal importance of axonal and Schwann cell BACE1 for remyelination of injured nerves.

  7. Quercetin alleviates high glucose-induced Schwann cell damage by autophagy

    Institute of Scientific and Technical Information of China (English)

    Ling Qu; Xiaochun Liang; Bei Gu; Wei Liu

    2014-01-01

    Quercetin can reverse high glucose-induced inhibition of neural cell proliferation, and therefore may have a neuroprotective effect in diabetic peripheral neuropathy. It is dififcult to obtain pri-mary Schwann cells and RSC96 cells could replace primary Schwann cells in studies of the role of autophagy in the mechanism underlying diabetic peripheral neuropathy. Here, we show that under high glucose conditions, there are fewer autophagosomes in immortalized rat RSC96 cells and primary rat Schwann cells than under control conditions, the proliferative activity of both cell types is signiifcantly impaired, and the expression of Beclin-1 and LC3, the molecular mark-ers for autophagy, is signiifcantly lower. After intervention with quercetin, the autophagic and proliferative activity of both cell types is rescued. These results suggest that quercetin can allevi-ate high glucose-induced damage to Schwann cells by autophagy.

  8. Neuregulin 1 functionalization of organic fibers for Schwann cell guidance

    Science.gov (United States)

    Tonazzini, Ilaria; Moffa, Maria; Pisignano, Dario; Cecchini, Marco

    2017-04-01

    The repair of peripheral nerve lesions is a clinical problem where the functional recovery is often far from being satisfactory, although peripheral nerves generally retain good potential for regeneration. Here, we develop a novel scaffold approach based on bioactive fibers of poly(ε-caprolactone) where nanotopographical guidance and neuregulin 1 (NRG1) cues are combined. We interface them with rat primary Schwann cells (SCs), the peripheral glial cells that drive initial regeneration of injured nerves, and found that the combination of NRG1 with parallel nano-fibrous topographies is effective in improving SC growth up to 72 h, alignment to fiber topography, and bipolar differentiation, opening original perspectives for nerve repair applications.

  9. A proteome map of primary cultured rat Schwann cells

    Directory of Open Access Journals (Sweden)

    Shen Mi

    2012-03-01

    Full Text Available Abstract Background Schwann cells (SCs are the principal glial cells of the peripheral nervous system with a wide range of biological functions. SCs play a key role in peripheral nerve regeneration and are involved in several hereditary peripheral neuropathies. The objective of this study was to gain new insight into the whole protein composition of SCs. Results Two-dimensional liquid chromatography coupled with tandem mass spectrometry (2D LC-MS/MS was performed to identify the protein expressions in primary cultured SCs of rats. We identified a total of 1,232 proteins, which were categorized into 20 functional classes. We also used quantitative real time RT-PCR and Western blot analysis to validate some of proteomics-identified proteins. Conclusion We showed for the first time the proteome map of SCs. Our data could serve as a reference library to provide basic information for understanding SC biology.

  10. Macrophage polarization in nerve injury:do Schwann cells play a role?

    Institute of Scientific and Technical Information of China (English)

    Jo Anne Stratton; Prajay T Shah

    2016-01-01

    In response to peripheral nerve injury, the inlfammatory response is almost entirely comprised of inifltrat-ing macrophages. Macrophages are a highly plastic, heterogenic immune cell, playing an indispensable role in peripheral nerve injury, clearing debris and regulating the microenvironment to allow for efifcient regen-eration. There are several cells within the microenvironment that likely interact with macrophages to support their function –most notably the Schwann cell, the glial cell of the peripheral nervous system. Schwann cells express several ligands that are known to interact with receptors expressed by macrophages, yet the effects of Schwann cells in regulating macrophage phenotype remains largely unexplored. This review discusses macrophages in peripheral nerve injury and how Schwann cells may regulate their behavior.

  11. Spatiotemporal distribution and function of N-cadherin in postnatal Schwann cells: A matter of adhesion?

    DEFF Research Database (Denmark)

    Corell, Mikael; Wicher, Grzegorz; Limbach, Christoph

    2010-01-01

    During embryonic development of the peripheral nervous system (PNS), the adhesion molecule neuronal cadherin (N-cadherin) is expressed by Schwann cell precursors and associated with axonal growth cones. N-cadherin expression levels decrease as precursors differentiate into Schwann cells....... In this study, we investigated the distribution of N-cadherin in the developing postnatal and adult rat peripheral nervous system. N-cadherin was found primarily in ensheathing glia throughout development, concentrated at neuron-glial or glial-glial contacts of the sciatic nerve, dorsal root ganglia (DRG...... studies of N-cadherin in these cultures, using the antagonist peptide INPISGQ, show a disruption of the attachment between Schwann cells, but no interference in the initial or long-term contact between Schwann cells and axons. We suggest that N-cadherin acts primarily in the adhesion between glial cells...

  12. Macrophage-Induced Blood Vessels Guide Schwann Cell-Mediated Regeneration of Peripheral Nerves.

    Science.gov (United States)

    Cattin, Anne-Laure; Burden, Jemima J; Van Emmenis, Lucie; Mackenzie, Francesca E; Hoving, Julian J A; Garcia Calavia, Noelia; Guo, Yanping; McLaughlin, Maeve; Rosenberg, Laura H; Quereda, Victor; Jamecna, Denisa; Napoli, Ilaria; Parrinello, Simona; Enver, Tariq; Ruhrberg, Christiana; Lloyd, Alison C

    2015-08-27

    The peripheral nervous system has remarkable regenerative capacities in that it can repair a fully cut nerve. This requires Schwann cells to migrate collectively to guide regrowing axons across a 'bridge' of new tissue, which forms to reconnect a severed nerve. Here we show that blood vessels direct the migrating cords of Schwann cells. This multicellular process is initiated by hypoxia, selectively sensed by macrophages within the bridge, which via VEGF-A secretion induce a polarized vasculature that relieves the hypoxia. Schwann cells then use the blood vessels as "tracks" to cross the bridge taking regrowing axons with them. Importantly, disrupting the organization of the newly formed blood vessels in vivo, either by inhibiting the angiogenic signal or by re-orienting them, compromises Schwann cell directionality resulting in defective nerve repair. This study provides important insights into how the choreography of multiple cell-types is required for the regeneration of an adult tissue.

  13. Regulation of Schwann cell proliferation in cultured segments of the adult rat sciatic nerve

    DEFF Research Database (Denmark)

    Svenningsen, Åsa Fex; Kanje, M

    1998-01-01

    Schwann cell proliferation was studied in cultured segments of the rat sciatic nerve by measurement of [3H] thymidine incorporation or through bromodeoxyuridine-(BrdU)-labelling and immunocytochemistry. The aim was to delineate mechanisms involved in the injury-induced proliferative response...... of Schwann cells. Removal of extracellular Ca2+ by addition of EGTA to the culture medium suppressed [3H] thymidine incorporation as did the calmodulin inhibitor 48/80. The Ca2+ ionophore A23187 increased incorporation. Staurosporin, an inhibitor of protein kinase C (PKC), suppressed [3H] thymidine...... together with morphological evaluation of myelin association showed that proliferation occurred in Schwann cells. The results are consistent with a model in which Schwann cell proliferation is enhanced by Ca2+ through activation of calmodulin-dependent and/or PKCdependent mechanisms. Inhibition is achieved...

  14. The HMGB1 signaling pathway activates the inflammatory response in Schwann cells.

    Science.gov (United States)

    Man, Li-Li; Liu, Fan; Wang, Ying-Jie; Song, Hong-Hua; Xu, Hong-Bo; Zhu, Zi-Wen; Zhang, Qing; Wang, Yong-Jun

    2015-10-01

    Schwann cells are not only myelinating cells, but also function as immune cells and express numerous innate pattern recognition receptors, including the Toll-like receptors. Injury to peripheral nerves activates an inflammatory response in Schwann cells. However, it is unclear whether specific endogenous damage-associated molecular pattern molecules are involved in the inflammatory response following nerve injury. In the present study, we demonstrate that a key damage-associated molecular pattern molecule, high mobility group box 1 (HMGB1), is upregulated following rat sciatic nerve axotomy, and we show colocalization of the protein with Schw-ann cells. HMGB1 alone could not enhance expression of Toll-like receptors or the receptor for advanced glycation end products (RAGE), but was able to facilitate migration of Schwann cells. When Schwann cells were treated with HMGB1 together with lipopolysaccharide, the expression levels of Toll-like receptors and RAGE, as well as inflammatory cytokines were upregulated. Our novel findings demonstrate that the HMGB1 pathway activates the inflammatory response in Schwann cells following peripheral nerve injury.

  15. Arrest of myelination and reduced axon growth when Schwann cells lack mTOR.

    Science.gov (United States)

    Sherman, Diane L; Krols, Michiel; Wu, Lai-Man N; Grove, Matthew; Nave, Klaus-Armin; Gangloff, Yann-Gaël; Brophy, Peter J

    2012-02-01

    In developing peripheral nerves, differentiating Schwann cells sort individual axons from bundles and ensheath them to generate multiple layers of myelin. In recent years, there has been an increased understanding of the extracellular and intracellular factors that initiate and stimulate Schwann cell myelination, together with a growing appreciation of some of the signaling pathways involved. However, our knowledge of how Schwann cell growth is regulated during myelination is still incomplete. The mammalian target of rapamycin (mTOR) is a core kinase in two major complexes, mTORC1 and mTORC2, that regulate cell growth and differentiation in a variety of mammalian cells. Here we show that elimination of mTOR from murine Schwann cells prevented neither radial sorting nor the initiation of myelination. However, normal postnatal growth of myelinating Schwann cells, both radially and longitudinally, was highly retarded. The myelin sheath in the mutant was much thinner than normal; nevertheless, sheath thickness relative to axon diameter (g-ratio) remained constant in both wild-type and mutant nerves from P14 to P90. Although axon diameters were normal in the mutant at the initiation of myelination, further growth as myelination proceeded was retarded, and this was associated with reduced phosphorylation of neurofilaments. Consistent with thinner axonal diameters and internodal lengths, conduction velocities in mutant quadriceps nerves were also reduced. These data establish a critical role for mTOR signaling in both the longitudinal and radial growth of the myelinating Schwann cell.

  16. Schwann cells in therapy of spinal cord injuries

    Directory of Open Access Journals (Sweden)

    Izabella Woszczycka-Korczyńska

    2013-07-01

    Full Text Available Schwann cells (SC have a special activity in the repair processes after injury of the nervous system because of the capability of differentiation, migration, proliferation and myelinization of axons. They enhance production of numerous neurotrophic factors, thus creating a permissive environment for axonal regeneration. Experimental studies using SC in neuronal transplants showed that these cells with their basal membrane with adhesion molecules are attractive material for neural prostheses facilitating axon growth. Moreover, SC can produce stable myelin, restoring normal function of the neuron. Transplantations of SC in myelin injury have been used in animal models of multiple sclerosis, Parkinson’s disease, and brain and spinal cord injuries. Because the transplanted SC have no ability to migrate within the normal nervous system, in many experiments SC derived from rat embryos were applied. Such cells migrated through normal nervous tissue and co-operated with host cells, their survival was longer, and myelin was not destroyed in multiple sclerosis. Also, fast recovery of motor activity in injured axons in rat spinal cord was observed, especially after transplantation of SC derived from skin progenitor cells or progenitor cells which have a phenotype characteristic for SC. Many authors have reported early apoptosis of transplanted SC, so a more complex repair strategy is needed that combines SC transplantation with other methods in order to achieve longer survival and optimal functional recovery following spinal cord injury.

  17. Effects of cerebrolysin on rat Schwann cells in vitro.

    Science.gov (United States)

    Lucas, Benjamin; Pinkernelle, Josephine; Fansa, Hisham; Keilhoff, Gerburg

    2014-06-01

    Although the peripheral nervous system (PNS) is capable of regeneration, these processes are limited. As a potential means to augment PNS regeneration, the effects of cerebrolysin (CL), a proteolytic peptide fraction, were tested in vitro on Schwann cell (SC) proliferation, stress resistance, phagocytic and cluster-forming capacity. Primary SC/fibrocyte co-cultures were prepared from dorsal root ganglia of 5-7-day-old rats. SCs were subjected to mechanical stress by media change and metabolic stress by serum glucose deprivation (SGD). Cell survival was assessed using MTT test. SC proliferation was determined by counting BrdU-labeled cells. SC clustering was studied by ImageJ analysis of S100 immunostaining. Wallerian degeneration (WD) was evaluated by measuring acetylcholine-esterase staining within sciatic nerves in vitro. It was found that CL caused no effect on MTT turnover in the tested doses. CL inhibited SC proliferation in a dose-dependent manner. Media change and additional SGD stress inhibited SC clustering. CL enhanced the reorganization of SC clusters and was able to counteract SGD-induced cluster defects. Moreover, CL accelerated WD in vitro. CL was able to enhance the functions of SCs that are relevant to nerve regeneration. Thus, our findings suggest that CL may be suitable for therapeutic usage to enhance PNS regeneration/reconstruction.

  18. Experimental study on the adhesion, migration and three-dimensional growth of Schwann cells on absorbable biological materials

    Institute of Scientific and Technical Information of China (English)

    王光林; 林卫; 杨志明; 裴福兴; 刘雷

    2003-01-01

    Objective: To study the adhesion, migration and three-dimentional growth of Schwann cells on PLA (polylactic acid) nonspinning fibre cloth and polyglycolic/polylactic acid (PLGA) fibres.Methods: Schwann cells/ECM gel solution and PLA nonspinning fibre cloth and PLGA fibres pretreated by collagen, polylysine and ECM were co-cultured. Then the migration and three-dimensional growth of Schwann cells on the fibres were observed under phase contrast microscope and laser scanning confocal microscope.Conclusions: ECM gel can facilitate the adhesion, growth and migration of Schwann cells on the seteroframe. It is a good integrating material for tissue engineering bioartificial nerve.

  19. Ribosomal trafficking is reduced in Schwann cells following induction of myelination

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    James M. Love

    2015-08-01

    Full Text Available Local synthesis of proteins within the Schwann cell periphery is extremely important for efficient process extension and myelination, when cells undergo dramatic changes in polarity and geometry. Still, it is unclear how ribosomal distributions are developed and maintained within Schwann cell projections to sustain local translation. In this multi-disciplinary study, we expressed a plasmid encoding a fluorescently labeled ribosomal subunit (L4-GFP in cultured primary rat Schwann cells. This enabled the generation of high-resolution, quantitative data on ribosomal distributions and trafficking dynamics within Schwann cells during early stages of myelination, induced by ascorbic acid treatment. Ribosomes were distributed throughout Schwann cell projections, with ~2-3 bright clusters along each projection. Clusters emerged within 1 day of culture and were maintained throughout early stages of myelination. Three days after induction of myelination, net ribosomal movement remained anterograde (directed away from the Schwann cell body, but ribosomal velocity decreased to about half the levels of the untreated group. Statistical and modeling analysis provided additional insight into key factors underlying ribosomal trafficking. Multiple regression analysis indicated that net transport at early time points was dependent on anterograde velocity, but shifted to dependence on anterograde duration at later time points. A simple, data-driven rate kinetics model suggested that the observed decrease in net ribosomal movement was primarily dictated by an increased conversion of anterograde particles to stationary particles, rather than changes in other directional parameters. These results reveal the strength of a combined experimental and theoretical approach in examining protein localization and transport, and provide evidence of an early establishment of ribosomal populations within Schwann cell projections with a reduction in trafficking following

  20. YAP/TAZ initiate and maintain Schwann cell myelination

    Science.gov (United States)

    Grove, Matthew; Kim, Hyukmin; Santerre, Maryline; Krupka, Alexander J; Han, Seung Baek; Zhai, Jinbin; Cho, Jennifer Y; Park, Raehee; Harris, Michele; Kim, Seonhee; Sawaya, Bassel E; Kang, Shin H; Barbe, Mary F; Cho, Seo-Hee; Lemay, Michel A; Son, Young-Jin

    2017-01-01

    Nuclear exclusion of the transcriptional regulators and potent oncoproteins, YAP/TAZ, is considered necessary for adult tissue homeostasis. Here we show that nuclear YAP/TAZ are essential regulators of peripheral nerve development and myelin maintenance. To proliferate, developing Schwann cells (SCs) require YAP/TAZ to enter S-phase and, without them, fail to generate sufficient SCs for timely axon sorting. To differentiate, SCs require YAP/TAZ to upregulate Krox20 and, without them, completely fail to myelinate, resulting in severe peripheral neuropathy. Remarkably, in adulthood, nuclear YAP/TAZ are selectively expressed by myelinating SCs, and conditional ablation results in severe peripheral demyelination and mouse death. YAP/TAZ regulate both developmental and adult myelination by driving TEAD1 to activate Krox20. Therefore, YAP/TAZ are crucial for SCs to myelinate developing nerve and to maintain myelinated nerve in adulthood. Our study also provides a new insight into the role of nuclear YAP/TAZ in homeostatic maintenance of an adult tissue. DOI: http://dx.doi.org/10.7554/eLife.20982.001 PMID:28124973

  1. ATP released by injured neurons activates Schwann cells

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    Samuele eNegro

    2016-05-01

    Full Text Available Injured nerve terminals of neuromuscular junctions (NMJs can regenerate. This remarkable and complex response is governed by molecular signals that are exchanged among the cellular components of this synapse: motor axon nerve terminal (MAT, perisynaptic Schwann cells (PSCs, and muscle fibre. The nature of signals that govern MAT regeneration is ill-known. In the present study the spider toxin α-Latrotoxin has been used as tool to investigate the mechanisms underlying peripheral neuroregeneration. Indeed this neurotoxin induces an acute, specific, localized and fully reversible damage of the presynaptic nerve terminal, and its action mimics the cascade of events that leads to nerve terminal degeneration in injured patients and in many neurodegenerative conditions. Here we provide evidence of an early release by degenerating neurons of ATP as alarm messenger, that contributes to the activation of a series of intracellular pathways within SCs that are crucial for nerve regeneration: Ca2+, cAMP, ERK1/2, and CREB. These results contribute to define the cross-talk taking place among degenerating nerve terminals and PSCs, involved in the functional recovery of the NMJ.

  2. YAP/TAZ initiate and maintain Schwann cell myelination.

    Science.gov (United States)

    Grove, Matthew; Kim, Hyukmin; Santerre, Maryline; Krupka, Alexander J; Han, Seung Baek; Zhai, Jinbin; Cho, Jennifer Y; Park, Raehee; Harris, Michele; Kim, Seonhee; Sawaya, Bassel E; Kang, Shin H; Barbe, Mary F; Cho, Seo-Hee; Lemay, Michel A; Son, Young-Jin

    2017-01-26

    Nuclear exclusion of the transcriptional regulators and potent oncoproteins, YAP/TAZ, is considered necessary for adult tissue homeostasis. Here we show that nuclear YAP/TAZ are essential regulators of peripheral nerve development and myelin maintenance. To proliferate, developing Schwann cells (SCs) require YAP/TAZ to enter S-phase and, without them, fail to generate sufficient SCs for timely axon sorting. To differentiate, SCs require YAP/TAZ to upregulate Krox20 and, without them, completely fail to myelinate, resulting in severe peripheral neuropathy. Remarkably, in adulthood, nuclear YAP/TAZ are selectively expressed by myelinating SCs, and conditional ablation results in severe peripheral demyelination and mouse death. YAP/TAZ regulate both developmental and adult myelination by driving TEAD1 to activate Krox20. Therefore, YAP/TAZ are crucial for SCs to myelinate developing nerve and to maintain myelinated nerve in adulthood. Our study also provides a new insight into the role of nuclear YAP/TAZ in homeostatic maintenance of an adult tissue.

  3. Electrical regulation of Schwann cells using conductive polypyrrole/chitosan polymers.

    Science.gov (United States)

    Huang, Jinghui; Hu, Xueyu; Lu, Lei; Ye, Zhengxu; Zhang, Quanyu; Luo, Zhuojing

    2010-04-01

    Electrical stimulation (ES) can dramatically enhance neurite outgrowth through conductive polymers and accelerate peripheral nerve regeneration in animal models of nerve injury. Therefore, conductive tissue engineering graft in combination with ES is a potential treatment for neural injuries. Conductive tissue engineering graft can be obtained by seeding Schwann cells on conductive scaffold. However, when ES is applied through the conductive scaffold, the impact of ES on Schwann cells has never been investigated. In this study, a biodegradable conductive composite made of conductive polypyrrole (PPy, 2.5%) and biodegradable chitosan (97.5%) was prepared in order to electrically stimulate Schwann cells. The tolerance of Schwann cells to ES was examined by a cell apoptosis assay. The growth of the cells was characterized using DAPI staining and a MTT assay. mRNA and protein levels of nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) in Schwann cells were assayed by RT-PCR and Western blotting, and the amount of NGF and BDNF secreted was determined by an ELISA assay. The results showed that the PPy/chitosan membranes supported cell adhesion, spreading, and proliferation with or without ES. Interestingly, ES applied through the PPy/chitosan composite dramatically enhanced the expression and secretion of NGF and BDNF when compared with control cells without ES. These findings highlight for the first time the possibility of enhancing nerve regeneration in conductive scaffolds through ES-increased neurotrophin secretion.

  4. Fingolimod induces the transition to a nerve regeneration promoting Schwann cell phenotype.

    Science.gov (United States)

    Heinen, André; Beyer, Felix; Tzekova, Nevena; Hartung, Hans-Peter; Küry, Patrick

    2015-09-01

    Successful regeneration of injured peripheral nerves is mainly attributed to the plastic behavior of Schwann cells. Upon loss of axons, these cells trans-differentiate into regeneration promoting repair cells which provide trophic support to regrowing axons. Among others, activation of cJun was revealed to be involved in this process, initiating the stereotypic pattern of Schwann cell phenotype alterations during Wallerian degeneration. Nevertheless, the ability of Schwann cells to adapt and therefore the nerve's potential to regenerate can be limited in particular after long term denervation or in neuropathies leading to incomplete regeneration only and thus emphasizing the need for novel therapeutic approaches. Here we stimulated primary neonatal and adult rat Schwann cells with Fingolimod/FTY720P and investigated its impact on the regeneration promoting phenotype. FTY720P activated a number of de-differentiation markers including cJun and interfered with maturation marker and myelin expression. Functionally, FTY720P treated Schwann cells upregulated growth factor expression and these cells enhanced dorsal root ganglion neurite outgrowth on inhibitory substrates. Our results therefore provide strong evidence that FTY720P application supports the generation of a repair promoting cellular phenotype and suggest that Fingolimod could be used as treatment for peripheral nerve injuries and diseases. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. Schwann cell cultures from human fetal dorsal root ganglia

    Institute of Scientific and Technical Information of China (English)

    Yaping Feng; Hui Zhu; Jiang Hao; Xinmin Wang; Shengping Wu; Li Bai; Xiangming Li; Yun Zha

    2009-01-01

    BACKGROUND:Previous studies have used many methods for in vitro Schwann cells (SCs) cul-tures and purification,such as single cell suspension and cytosine arabinoside.However,it has been difficult to obtain sufficient cellular density,and the procedures have been quite tedious.OBJECTIVE:To investigate the feasibility of culturing high-density SCs using fetal human dorsal root ganglion tissue explants.DESIGN,TIME AND SETTING:Cell culture and immunohistochemistry were performed at the Cen-tral Laboratory of Kunming General Hospital of Chinese PLA between March 2001 and October 2008.MATERIALS:Culture media containing 10% fetal bovine serum,as well as 0.2% collagenase and 0.25% trypsin were purchased from Gibco,USA;mouse anti-human S-100 monoclonal antibody and goat anti-mouse IgG labeled with horseradish peroxidase were provided by Beijing Institute of Bi-ological Products,China.METHODS:Primarily cultured SCs were dissociated from dorsal root ganglia of human aborted fe-tuses at 4-6 months pregnancy.Following removal of the dorsal root ganglion perineurium,the gan-glia were dissected into tiny pieces and digested with 0.2% collagenase and 0.25% trypsin (volume ratio 1:1),then explanted and cultured.SC purification was performed with 5 mL 10% fetal bovine serum added to the culture media,followed by differential adhesion.MAIN OUTCOME MEASURES:SCs morphology was observed under inverted phase contrast light microscopy.SC purity was evaluated according to percentage of S-100 immunostained cells.RESULTS:SCs were primarily cultured for 5-6 days and then subcultured for 4-5 passages.The highly enriched SC population reached > 95% purity and presented with normal morphology.CONCLUSION:A high purity of SCs was obtained with culture methods using human fetal dorsal root ganglion tissue explants.

  6. Differentiation of adult human bone marrow mesenchymal stem cells into Schwann-like cells in vitro

    Institute of Scientific and Technical Information of China (English)

    YANG Li-ye; ZHENG Jia-kun; WANG Chao-yang; LI Wen-yu

    2005-01-01

    Objective: To investigate the differentiative capability of adult human bone marrow mesenchymal stem cells (BMSCs) into Schwann-like cells. Methods: Bone marrows were aspirated from healthy donors and mononuclear cells were separated by Percoll lymphocytes separation liquid (1.073 g/ml) with centrifugation, cells were cultured in DMEM/F12 (1:1) medium containing 10% fetal bovine serum (FBS), 20 ng/ml epidermal growth factor (EGF) and 20 ng/ml basic fibroblast growth factor (bFGF). Cells of passage 1 were identified with immunocytochemistry. Conclusions: Bone marrow contains the stem cells with the ability of differentiating into Schwann-like cells, which may represent an alternative stem cell sources for neural transplantation.

  7. Direct Genesis of Functional Rodent and Human Schwann Cells from Skin Mesenchymal Precursors

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    Matthew P. Krause

    2014-07-01

    Full Text Available Recent reports of directed reprogramming have raised questions about the stability of cell lineages. Here, we have addressed this issue, focusing upon skin-derived precursors (SKPs, a dermally derived precursor cell. We show by lineage tracing that murine SKPs from dorsal skin originate from mesenchymal and not neural crest-derived cells. These mesenchymally derived SKPs can, without genetic manipulation, generate functional Schwann cells, a neural crest cell type, and are highly similar at the transcriptional level to Schwann cells isolated from the peripheral nerve. This is not a mouse-specific phenomenon, since human SKPs that are highly similar at the transcriptome level can be made from neural crest-derived facial and mesodermally derived foreskin dermis and the foreskin SKPs can make myelinating Schwann cells. Thus, nonneural crest-derived mesenchymal precursors can differentiate into bona fide peripheral glia in the absence of genetic manipulation, suggesting that developmentally defined lineage boundaries are more flexible than widely thought.

  8. Regulation of retinoid receptors by retinoic acid and axonal contact in Schwann cells.

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    Maria-Jesus Latasa

    Full Text Available BACKGROUND: Schwann cells (SCs are the cell type responsible for the formation of the myelin sheath in the peripheral nervous system (PNS. As retinoic acid (RA and other retinoids have a profound effect as regulators of the myelination program, we sought to investigate how their nuclear receptors levels were regulated in this cell type. METHODOLOGY/PRINCIPAL FINDINGS: In the present study, by using Schwann cells primary cultures from neonatal Wistar rat pups, as well as myelinating cocultures of Schwann cells with embryonic rat dorsal root ganglion sensory neurons, we have found that sustained expression of RXR-γ depends on the continuous presence of a labile activator, while axonal contact mimickers produced an increase in RXR-γ mRNA and protein levels, increment that could be prevented by RA. The upregulation by axonal contact mimickers and the transcriptional downregulation by RA were dependent on de novo protein synthesis and did not involve changes in mRNA stability. On the other hand, RAR-β mRNA levels were only slightly modulated by axonal contact mimickers, while RA produced a strong transcriptional upregulation that was independent of de novo protein synthesis without changes in mRNA stability. CONCLUSIONS/SIGNIFICANCE: All together, our results show that retinoid receptors are regulated in a complex manner in Schwann cells, suggesting that they could have a prominent role as regulators of Schwann cell physiology.

  9. Differentiation of rat embryonic neural stem cells promoted by co-cultured Schwann cells

    Institute of Scientific and Technical Information of China (English)

    万虹; 安沂华; 张泽舜; 张亚卓; 王忠诚

    2003-01-01

    Objective To explore the factors which induce differentiation of embryonic neural stem cells. Methods Rat embryonic neural stem cells were co-cultured with newborn rat Schwann cells in serum-free medium. The phenotype and specific-markers including tubulin-β, glial fibrillary acidic protein (GFAP) and galactorcerebroside (GalC), were domonstrated by phase contrast microscopy and double immunofluorescence staining. Results Overall, 80%±5% of neural stem cells protruded several elongated processes and expressed tubulin-β antigen at high levels, while 20±3% of them protruded several short processes and were GalC or GFAP positive. Conclusion The factors secreted by Schwann cells could induce rat embryonic neural stem cell to differentiate.

  10. Functional dissection of the Oct6 schwann cell enhancer reveals an essential role for dimeric sox10 binding

    NARCIS (Netherlands)

    N.B. Jagalur (Noorjahan ); M. Ghazvini (Mehrnaz); W. Mandemakers (Wim); S. Driegen (Siska); A. Maas (Alex); E.A. Jones (Erin); F.G. Grosveld (Frank); M. Jaegle (Martine); J. Svaren (John); D.N. Meijer (Dies)

    2011-01-01

    textabstractThe POU domain transcription factor Pou3f1 (Oct6/Scip/Tst1) initiates the transition from ensheathing, promyelinating Schwann cells to myelinating cells. Axonal and other extracellular signals regulate Oct6 expression through the Oct6 Schwann cell enhancer (SCE), which is both required a

  11. SncRNA715 Inhibits Schwann Cell Myelin Basic Protein Synthesis.

    Science.gov (United States)

    Müller, Christina; Hochhaus, Nina M; Fontana, Xavier; Luhmann, Heiko J; White, Robin

    2015-01-01

    Myelin basic proteins (MBP) are major constituents of the myelin sheath in the central nervous system (CNS) and the peripheral nervous system (PNS). In the CNS Mbp translation occurs locally at the axon-glial contact site in a neuronal activity-dependent manner. Recently we identified the small non-coding RNA 715 (sncRNA715) as a key inhibitor of Mbp translation during transport in oligodendrocytes. Mbp mRNA localization in Schwann cells has been observed, but has not been investigated in much detail. Here we could confirm translational repression of Mbp mRNA in Schwann cells. We show that sncRNA715 is expressed and its levels correlate inversely with MBP in cultured Schwann cells and in the sciatic nerve in vivo. Furthermore we could reduce MBP protein levels in cultured Schwann cells by increasing the levels of the inhibitory sncRNA715. Our findings suggest similarities in sncRNA715-mediated translational repression of Mbp mRNA in oligodendrocytes and Schwann cells.

  12. Differentiation of Adipose-derived Stem Cells into Schwann Cell Phenotype in Comparison with Bone Marrow Stem Cells

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    Zolikha Golipoor

    2010-06-01

    Full Text Available Objective(sBone marrow is the traditional source of human multipotent mesenchymal stem cells (MSCs, but adipose tissue appears to be an alternative and more readily available source. In this study, rat adipose-derived stem cells (ADSCs were induced to differentiate into Schwann-like cells and compared with rat bone marrow stem cells (BMSCs for their Schwann-like cells differentiation potential. Materials and MethodsBMSCs and ADSCs were characterized for expression of MSCs-specific markers, osteogenic and adipogenic differentiation. They were induced to differentiate into Schwann-like cells and analyzed for expression of the Schwann specific markers. The immunocytochemical differentiation markers were S-100 and real time quantitative Real-time polymerase chain reaction (RT-PCR markers were S100, P75 and glial fibrillary acidic protein (GFAP. 3-(4, 5-Dimethylthiazol- 2-yl-2, 5-diphenyltetrazolium bromide (MTT assay and Annexin V-Fluorescein isothiocyanate (FITC/ Propidium iodide (PI double labeling method were employed to detect early stage cell apoptosis.ResultsBMSCs and ADSCs showed similarities in expression of the MSC-specific markers, osteogenic and adipogenic differentiation. Both quantitative RT-PCR and immunocytochemical analysis demonstrated that BMSCs and ADSCs had equal expression of the Schwann-specific markers following Schwann-like cells differentiation. However, gene expression of P75 was higher in BMSCs compared with ADSCs. MTT assay and flow cytometry found that of the total BMSCs and ADSCs in the culture medium, 20% to 30% of the cells died, but the remaining cell population remained strongly attached to the substrate and differentiated.ConclusionComparative analysis showed that Schwann-like cell differentiation potential of ADSCs was slightly decreased in comparison with BMSCs. Therefore, BMSCs are more favorable choice than ADSCs for tissue engineering.

  13. An effective technique for isolating adult activated Schwann cells

    Institute of Scientific and Technical Information of China (English)

    Jifei Zhang; Lianhong Jin; Yuzhen Zhao

    2006-01-01

    BACKGROUND: Schwann cells (SCs) are neuroglial cells of peripheral nerve and play a key role in repairing peripheral nerve injury; therefore, it provides an important evidence for transplantation of SCs which are characterized by active proliferation and adult high-purity in vitro after nerve injury in clinic, and also develops a new therapeutic way for nerve injury.OBJECTIVE: To investigate an effective technique for isolating adult activated Schwann cells.DESIGN: Controlled observational study.SETTING: Mudanjiang Medical College.MATERIALS: The experiment was completed at the Department of Medical Genetics of Harbin Medical University from March 2003 to April 2005. Health female Wistar rats, aged 2 months, weighting 150-160 g, were randomly divided into 3 groups with 5 in each group.METHODS: The right sciatic nerves from 15 Wistar rats were exposed and transected at the mid thigh under pentobarbital anesthesia (4 mg/kg, I.p). Seven days later, the distal segments of the predegenerated nerves were removed and used to produce adult Schwann cell cultures. The distal segment of the predegenerated nerve, 20 mm in length, was resected. The nerve was cut into pieces 1 mm in length and incubated for 3 hours under CO2 at 37 ℃ with an enzyme mixture of 0.05% collagenase/dispase. Rats were divided into 3 groups:① Group 1: The nerve fragments were explanted in poly-L-lysine and laminin-coated dishes with BS medium from the 1st to the 6th day. On the 6th day, the fragments were removed into a new poly-L-lysine-laminin-coated dish and the BS medium was changed to BS with 10% FBS. The nerve fragments were replaced repeatedly in the same way in new dishes on the 12th and the 18th days. ②Group 2: For the first 3 days, the nerve fragments were fed with BS with 10% FBS. This medium was changed to BS medium on the third day. The nerve fragments were removed to another dish on day 6 and BS medium was changed to BS with 25 mL/L FBS. Hereafter the culture method was the same as

  14. Schwann Cells Transplantation Promoted and the Repair of Brain Stem Injury in Rats

    Institute of Scientific and Technical Information of China (English)

    HONG WAN; YI-HUA AN; MEI-ZHEN SUN; YA-ZHUO ZHANG; ZHONG-CHENG WANG

    2003-01-01

    To explore the possibility of Schwann cells transplantation to promote the repair of injured brain stem reticular structure in rats. Methods Schwann cells originated from sciatic nerves of 1 to 2-day-old rats were expanded and labelled by BrdU in vitro, transplanted into rat brain stem reticular structure that was pre-injured by electric needle stimulus. Immunohistochemistry and myelin-staining were used to investigate the expression of BrdU, GAP-43 and new myelination respectively. Results BrdU positive cells could be identified for up to 8 months and their number increased by about 23%, which mainly migrated toward injured ipsilateral cortex. The GAP-43expression reached its peak in 1 month after transplantation and was significantly higher than that in the control group. New myelination could be seen in destructed brain stem areas. Conclusion The transplantation of Schwann cells can promote the restoration of injured brain stem reticular structure.

  15. Axon degeneration: make the Schwann cell great again

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    Keit Men Wong

    2017-01-01

    Full Text Available Axonal degeneration is a pivotal feature of many neurodegenerative conditions and substantially accounts for neurological morbidity. A widely used experimental model to study the mechanisms of axonal degeneration is Wallerian degeneration (WD, which occurs after acute axonal injury. In the peripheral nervous system (PNS, WD is characterized by swift dismantling and clearance of injured axons with their myelin sheaths. This is a prerequisite for successful axonal regeneration. In the central nervous system (CNS, WD is much slower, which significantly contributes to failed axonal regeneration. Although it is well-documented that Schwann cells (SCs have a critical role in the regenerative potential of the PNS, to date we have only scarce knowledge as to how SCs 'sense' axonal injury and immediately respond to it. In this regard, it remains unknown as to whether SCs play the role of a passive bystander or an active director during the execution of the highly orchestrated disintegration program of axons. Older reports, together with more recent studies, suggest that SCs mount dynamic injury responses minutes after axonal injury, long before axonal breakdown occurs. The swift SC response to axonal injury could play either a pro-degenerative role, or alternatively a supportive role, to the integrity of distressed axons that have not yet committed to degenerate. Indeed, supporting the latter concept, recent findings in a chronic PNS neurodegeneration model indicate that deactivation of a key molecule promoting SC injury responses exacerbates axonal loss. If this holds true in a broader spectrum of conditions, it may provide the grounds for the development of new glia-centric therapeutic approaches to counteract axonal loss.

  16. The RNA-binding protein human antigen R controls global changes in gene expression during Schwann cell development.

    NARCIS (Netherlands)

    Iruarrizaga-Lejarreta, M.; Varela-Rey, M.; Lozano, J.J.; Fernandez-Ramos, D.; Rodriguez-Ezpeleta, N.; Embade, N.; Lu, S.C.; Kraan, P.M. van der; Blaney Davidson, E.N.; Gorospe, M.; Mirsky, R.; Jessen, K.R.; Aransay, A.M.; Mato, J.M.; Martinez-Chantar, M.L.; Woodhoo, A.

    2012-01-01

    An important prerequisite to myelination in peripheral nerves is the establishment of one-to-one relationships between axons and Schwann cells. This patterning event depends on immature Schwann cell proliferation, apoptosis, and morphogenesis, which are governed by coordinated changes in gene expres

  17. Hyperbaric oxygen therapy combined with Schwann cell transplantation promotes spinal cord injury recovery

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    Chuan-gang Peng

    2015-01-01

    Full Text Available Schwann cell transplantation and hyperbaric oxygen therapy each promote recovery from spinal cord injury, but it remains unclear whether their combination improves therapeutic results more than monotherapy. To investigate this, we used Schwann cell transplantation via the tail vein, hyperbaric oxygen therapy, or their combination, in rat models of spinal cord contusion injury. The combined treatment was more effective in improving hindlimb motor function than either treatment alone; injured spinal tissue showed a greater number of neurite-like structures in the injured spinal tissue, somatosensory and motor evoked potential latencies were notably shorter, and their amplitudes greater, after combination therapy than after monotherapy. These findings indicate that Schwann cell transplantation combined with hyperbaric oxygen therapy is more effective than either treatment alone in promoting the recovery of spinal cord in rats after injury.

  18. Schwann cells and their transcriptional network: Evolution of key regulators of peripheral myelination.

    Science.gov (United States)

    Stolt, C Claus; Wegner, Michael

    2016-06-15

    As derivatives of the neural crest, Schwann cells represent a vertebrate invention. Their development and differentiation is under control of a newly constructed, vertebrate-specific regulatory network that contains Sox10, Oct6 and Krox20 as cornerstones and central regulators of peripheral myelination. In this review, we discuss the function and relationship of these transcription factors among each other and in the context of their regulatory network, and present ideas of how neofunctionalization may have helped to recruit them to their novel task in Schwann cells. This article is part of a Special Issue entitled SI: Myelin Evolution.

  19. Myosin-Va-dependent cell-to-cell transfer of RNA from Schwann cells to axons.

    Science.gov (United States)

    Sotelo, José R; Canclini, Lucía; Kun, Alejandra; Sotelo-Silveira, José R; Xu, Lei; Wallrabe, Horst; Calliari, Aldo; Rosso, Gonzalo; Cal, Karina; Mercer, John A

    2013-01-01

    To better understand the role of protein synthesis in axons, we have identified the source of a portion of axonal RNA. We show that proximal segments of transected sciatic nerves accumulate newly-synthesized RNA in axons. This RNA is synthesized in Schwann cells because the RNA was labeled in the complete absence of neuronal cell bodies both in vitro and in vivo. We also demonstrate that the transfer is prevented by disruption of actin and that it fails to occur in the absence of myosin-Va. Our results demonstrate cell-to-cell transfer of RNA and identify part of the mechanism required for transfer. The induction of cell-to-cell RNA transfer by injury suggests that interventions following injury or degeneration, particularly gene therapy, may be accomplished by applying them to nearby glial cells (or implanted stem cells) at the site of injury to promote regeneration.

  20. Pro-neurogenic effects of andrographolide on RSC96 Schwann cells in vitro

    Science.gov (United States)

    Xu, Fuben; Wu, Huayu; Zhang, Kun; Lv, Peizhen; Zheng, Li; Zhao, Jinmin

    2016-01-01

    Nerve regeneration remains a challenge to the treatment of peripheral nerve injury. Andrographolide (Andro) is the main active constituent of Andrographis paniculata, which has been applied in the treatment of several diseases, including inflammation, in ancient China. Andro has been reported to facilitate the reduction of edema and to exert analgesic effects in the treatment of various diseases. These findings suggest that Andro may be considered a promising anti-inflammatory agent that may suppress destruction and accelerate proliferation of Schwann cells following peripheral nerve injury. In the present study, the effects of Andro on RSC96 cells were investigated in vitro. The RSC96 cell line is a spontaneously immortalized rat Schwann cell line, which was originally derived from a long-term culture of rat primary Schwann cells. RSC96 cells were treated with a range of 0 to 50 µM Andro prior to the MTT assay. Cell proliferation, morphology, synthesis and nerve-specific gene expression were performed to detect the effect of Andro on RSC96 cells. The results of the present study demonstrated that the recommended doses of Andro ranged between 0.78 and 12.5 µM, among which the most obvious response was observed when used at 3.125 µM (PAndro groups compared with the control group (PAndro was able to promote the gene expression of glial cell line-derived neurotrophic factor, brain-derived neurotrophic factor, ciliary neurotrophic factor, and the specific Schwann cell marker S100β (PAndro groups. These results indicated that Andro may accelerate proliferation of RSC96 cells in vitro, whilst maintaining the Schwann cell phenotype; therefore, the present study may provide valuable evidence for the further exploration of the effects of Andro on peripheral nerves. PMID:27599453

  1. Pro‑neurogenic effects of andrographolide on RSC96 Schwann cells in vitro.

    Science.gov (United States)

    Xu, Fuben; Wu, Huayu; Zhang, Kun; Lv, Peizhen; Zheng, Li; Zhao, Jinmin

    2016-10-01

    Nerve regeneration remains a challenge to the treatment of peripheral nerve injury. Andrographolide (Andro) is the main active constituent of Andrographis paniculata, which has been applied in the treatment of several diseases, including inflammation, in ancient China. Andro has been reported to facilitate the reduction of edema and to exert analgesic effects in the treatment of various diseases. These findings suggest that Andro may be considered a promising anti‑inflammatory agent that may suppress destruction and accelerate proliferation of Schwann cells following peripheral nerve injury. In the present study, the effects of Andro on RSC96 cells were investigated in vitro. The RSC96 cell line is a spontaneously immortalized rat Schwann cell line, which was originally derived from a long‑term culture of rat primary Schwann cells. RSC96 cells were treated with a range of 0 to 50 µM Andro prior to the MTT assay. Cell proliferation, morphology, synthesis and nerve‑specific gene expression were performed to detect the effect of Andro on RSC96 cells. The results of the present study demonstrated that the recommended doses of Andro ranged between 0.78 and 12.5 µM, among which the most obvious response was observed when used at 3.125 µM (PAndro groups compared with the control group (PAndro was able to promote the gene expression of glial cell line‑derived neurotrophic factor, brain‑derived neurotrophic factor, ciliary neurotrophic factor, and the specific Schwann cell marker S100β (PAndro groups. These results indicated that Andro may accelerate proliferation of RSC96 cells in vitro, whilst maintaining the Schwann cell phenotype; therefore, the present study may provide valuable evidence for the further exploration of the effects of Andro on peripheral nerves.

  2. pSVPoMcat modifying Schwann cell to protect injured spinal neurons in rats

    Institute of Scientific and Technical Information of China (English)

    陈礼刚; 高立达; 朴永旭; 毛伯镛; 曾凡俊

    2002-01-01

    Objective: To investigate the protective effect of pSVPoMcat (myelin basic protein microgene)modifying Schwann cell on injured spinal neurons.Methods: A model of rat spinal cord injured by hemisection was used. One hundred and twenty healthy SD rats of both sexes weighing 250-300 g were divided into three groups: Group A (n=40, treated with implantation of pSVPoMcat modifying Schwann cell), Group B (n= 40, treated with implantation of Schwann cell only) and Group C (n=400, treated with sham operation as the control). One week after operation the rat functional recovery was observed dynamically by using combined behavioral score (CBS) and cortical somatasensory evoked potentials, the spinal cord sections were stained by Nissl, acid phosphatase enzyme histochemistry and cell apoptosis was examined by methye green, terminal deoxynucleotidyl and the dUTP Nick end labeling technique. Quantitative analysis was done by computer image analysis system.Results: In Group A the injured neurons recovered well morphologically. The imaging analysis showed a result of Group A>Group B>Group C in the size of the neurons (P<0.01). The percentage of ACP (acid phosphatase) stained area and the rate of apoptosis sequence were groups ASchwann cell implantation has protective effect on injured spinal neurons and promotes recovery of injured spinal cord function in rats.

  3. miR-21 promotes the differentiation of hair follicle-derived neural crest stem cells into Schwann cells

    Institute of Scientific and Technical Information of China (English)

    Yuxin Ni; Kaizhi Zhang; Xuejuan Liu; Tingting Yang; Baixiang Wang; Li Fu; Lan A; Yanmin Zhou

    2014-01-01

    Hair follicle-derived neural crest stem cells can be induced to differentiate into Schwann cells in vivo and in vitro. However, the underlying regulatory mechanism during cell differentiation remains poorly understood. This study isolated neural crest stem cells from human hair folli-cles and induced them to differentiate into Schwann cells. Quantitative RT-PCR showed that microRNA (miR)-21 expression was gradually increased during the differentiation of neural crest stem cells into Schwann cells. After transfection with the miR-21 agonist (agomir-21), the differentiation capacity of neural crest stem cells was enhanced. By contrast, after transfection with the miR-21 antagonist (antagomir-21), the differentiation capacity was attenuated. Further study results showed that SOX-2 was an effective target of miR-21. Without compromising SOX2 mRNA expression, miR-21 can down-regulate SOX protein expression by binding to the 3′-UTR of miR-21 mRNA. Knocking out the SOX2 gene from the neural crest stem cells significantly reversed the antagomir-21 inhibition of neural crest stem cells differentiating into Schwann cells. The results suggest that miR-21 expression was increased during the differentiation of neural crest stem cells into Schwann cells and miR-21 promoted the differentiation through down-regu-lating SOX protein expression by binding to the 3′-UTR of SOX2 mRNA.

  4. Neurite outgrowth is significantly increased by the simultaneous presentation of Schwann cells and moderate exogenous electric fields.

    Science.gov (United States)

    Koppes, Abigail N; Seggio, Angela M; Thompson, Deanna M

    2011-08-01

    Axonal extension is influenced by a variety of external guidance cues; therefore, the development and optimization of a multi-faceted approach is probably necessary to address the intricacy of functional regeneration following nerve injury. In this study, primary dissociated neonatal rat dorsal root ganglia neurons and Schwann cells were examined in response to an 8 h dc electrical stimulation (0-100 mV mm(-1)). Stimulated samples were then fixed immediately, immunostained, imaged and analyzed to determine Schwann cell orientation and characterize neurite outgrowth relative to electric field strength and direction. Results indicate that Schwann cells are viable following electrical stimulation with 10-100 mV mm(-1), and retain a normal morphology relative to unstimulated cells; however, no directional bias is observed. Neurite outgrowth was significantly enhanced by twofold following exposure to either a 50 mV mm(-1) electric field (EF) or co-culture with unstimulated Schwann cells by comparison to neurons cultured alone. Neurite outgrowth was further increased in the presence of simultaneously applied cues (Schwann cells + 50 mV mm(-1) dc EF), exhibiting a 3.2-fold increase over unstimulated control neurons, and a 1.2-fold increase over either neurons cultured with unstimulated Schwann cells or the electrical stimulus alone. These results indicate that dc electric stimulation in combination with Schwann cells may provide synergistic guidance cues for improved axonal growth relevant to nerve injuries in the peripheral nervous system.

  5. Estrogen and progesterone stimulate Schwann cell proliferation in a sex- and age-dependent manner

    DEFF Research Database (Denmark)

    Svenningsen, Åsa Fex; Kanje, M

    1999-01-01

    The effects of estrogen and progesterone on Schwann cell proliferation were studied in cultured segments of the rat sciatic nerve from adult male, female, and newborn rats, by measurement of [3H thymidine incorporation or bromo-deoxy-uridine- (BrdU)-labelling and immunocytochemistry. Estrogen (100...

  6. The QKI-6 and QKI-7 RNA binding proteins block proliferation and promote Schwann cell myelination.

    Directory of Open Access Journals (Sweden)

    Daniel Larocque

    Full Text Available BACKGROUND: The quaking viable (qk(v mice have uncompacted myelin in their central and peripheral nervous system (CNS, PNS. The qk gene encodes 3 major alternatively spliced isoforms that contain unique sequence at their C-terminus dictating their cellular localization. QKI-5 is a nuclear isoform, whereas QKI-6 and QKI-7 are cytoplasmic isoforms. The qk(v mice harbor an enhancer/promoter deletion that prevents the expression of isoforms QKI-6 and QKI-7 in myelinating cells resulting in a dysmyelination phenotype. It was shown that QKI regulates the differentiation of oligodendrocytes, the myelinating cells of the CNS, however, little is known about the role of the QKI proteins, or RNA binding proteins in PNS myelination. METHODOLOGY/PRINCIPAL FINDINGS: To define the role of the QKI proteins in PNS myelination, we ectopically expressed QKI-6 and QKI-7 in primary rat Schwann cell/neuron from dorsal root ganglia cocultures. We show that the QKI isoforms blocked proliferation and promoted Schwann cell differentiation and myelination. In addition, these events were coordinated with elevated proteins levels of p27(KIP1 and myelin basic protein (MBP, markers of Schwann cell differentiation. QKI-6 and QKI-7 expressing co-cultures contained myelinated fibers that had directionality and contained significantly thicker myelin, as assessed by electron microscopy. Moreover, QKI-deficient Schwann cells had reduced levels of MBP, p27(KIP1 and Krox-20 mRNAs, as assessed by quantitative RT-PCR. CONCLUSIONS/SIGNIFICANCE: Our findings suggest that the QKI-6 and QKI-7 RNA binding proteins are positive regulators of PNS myelination and show that the QKI RNA binding proteins play a key role in Schwann cell differentiation and myelination.

  7. Adipose-Derived Stem Cells Promote Peripheral Nerve Regeneration In Vivo without Differentiation into Schwann-Like Lineage.

    Science.gov (United States)

    Sowa, Yoshihiro; Kishida, Tsunao; Imura, Tetsuya; Numajiri, Toshiaki; Nishino, Kenichi; Tabata, Yasuhiko; Mazda, Osam

    2016-02-01

    During recent decades, multipotent stem cells were found to reside in the adipose tissue, and these adipose-derived stem cells were shown to play beneficial roles, like those of Schwann cells, in peripheral nerve regeneration. However, it has not been well established whether adipose-derived stem cells offer beneficial effects to peripheral nerve injuries in vivo as Schwann cells do. Furthermore, the in situ survival and differentiation of adipose-derived stem cells after transplantation at the injured peripheral nerve tissue remain to be fully elucidated. Adipose-derived stem cells and Schwann cells were transplanted with gelatin hydrogel tubes at the artificially blunted sciatic nerve lesion in mice. Neuroregenerative abilities of them were comparably estimated. Cre-loxP-mediated fate tracking was performed to visualize survival in vivo of transplanted adipose-derived stem cells and to investigate whether they differentiated into Schwann linage cells at the peripheral nerve injury site. The transplantation of adipose-derived stem cells promoted regeneration of axons, formation of myelin, and restoration of denervation muscle atrophy to levels comparable to those achieved by Schwann cell transplantation. The adipose-derived stem cells survived for at least 4 weeks after transplantation without differentiating into Schwann cells. Transplanted adipose-derived stem cells did not differentiate into Schwann cells but promoted peripheral nerve regeneration at the injured site. The neuroregenerative ability was comparable to that of Schwann cells. Adipose-derived stem cells at an undifferentiated stage may be used as an alternative cell source for autologous cell therapy for patients with peripheral nerve injury.

  8. Hydrogen sulfide is essential for Schwann cell responses to peripheral nerve injury.

    Science.gov (United States)

    Park, Byung Sun; Kim, Hyun-Wook; Rhyu, Im Joo; Park, Chan; Yeo, Seung Geun; Huh, Youngbuhm; Jeong, Na Young; Jung, Junyang

    2015-01-01

    Hydrogen sulfide (H2 S) functions as a physiological gas transmitter in both normal and pathophysiological cellular events. H2 S is produced from substances by three enzymes: cystathionine β-synthase (CBS), cystathionine γ-lyase (CSE), and 3-mercaptopyruvate sulfurtransferase (MST). In human tissues, these enzymes are involved in tissue-specific biochemical pathways for H2 S production. For example, CBS and cysteine aminotransferase/MST are present in the brain, but CSE is not. Thus, we examined the expression of H2 S production-related enzymes in peripheral nerves. Here, we found that CSE and MST/cysteine aminotransferase, but not CBS, were present in normal peripheral nerves. In addition, injured sciatic nerves in vivo up-regulated CSE in Schwann cells during Wallerian degeneration (WD); however, CSE was not up-regulated in peripheral axons. Using an ex vivo sciatic nerve explant culture, we found that the inhibition of H2 S production broadly prevented the process of nerve degeneration, including myelin fragmentation, axonal degradation, Schwann cell dedifferentiation, and Schwann cell proliferation in vitro and in vivo. Thus, these results indicate that H2 S signaling is essential for Schwann cell responses to peripheral nerve injury. Hydrogen sulfide (H2 S) functions as a physiological gas transmitter in both normal and pathophysiological cellular events. H2 S is produced from cystathionine β-synthase (CBS), cystathionine γ-lyase (CSE), and 3-mercaptopyruvate sulfur transferase (MST). Here, we found that CSE and MST/CAT were present in normal peripheral nerves. Injured static nerves in vivo up-regulated CSE in Schwann cells during Wallerian degeneration, but CSE was not up-regulated in peripheral axons.

  9. Construction of nerve guide conduits from cellulose/soy protein composite membranes combined with Schwann cells and pyrroloquinoline quinone for the repair of peripheral nerve defect

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Lihua [Department of Biomedical Engineering, School of Basic Medical Sciences, Wuhan University, Wuhan 430071 (China); Center of Molecular Medicine, School of Medicine, Hubei University of Arts and Sciences, Xiangyang 441053 (China); Gan, Li; Liu, Yongming; Tian, Weiqun; Tong, Zan [Department of Biomedical Engineering, School of Basic Medical Sciences, Wuhan University, Wuhan 430071 (China); Wang, Xiong; Huselstein, Celine [Ingénierie Moléculaire et Physiopathologie Articulaire (IMoPA), UMR 7365 CNRS – Université de Lorraine, Biopôle, 54500 Vandoeuvre-lès-Nancy (France); Chen, Yun, E-mail: yunchen@whu.edu.cn [Department of Biomedical Engineering, School of Basic Medical Sciences, Wuhan University, Wuhan 430071 (China)

    2015-02-20

    Regeneration and functional reconstruction of peripheral nerve defects remained a significant clinical challenge. Nerve guide conduits, with seed cells or neurotrophic factors (NTFs), had been widely used to improve the repair and regeneration of injured peripheral nerve. Pyrroloquinoline quinone (PQQ) was an antioxidant that can stimulate nerve growth factors (NGFs) synthesis and accelerate the Schwann cells (SCs) proliferation and growth. In present study, three kinds of nerve guide conduits were constructed: one from cellulose/SPI hollow tube (CSC), another from CSC combined with SCs (CSSC), and the third one from CSSC combined with PQQ (CSSPC), respectively. And then they were applied to bridge and repair the sciatic nerve defect in rats, using autograft as control. Effects of different nerve guide conduits on the nerve regeneration were comparatively evaluated by general analysis, sciatic function index (SFI) and histological analysis (HE and TEM). Newly-formed regenerative nerve fibers were observed and running through the transparent nerve guide conduits 12 weeks after surgery. SFI results indicated that the reconstruction of motor function in CSSPC group was better than that in CSSC and CSC groups. HE images from the cross-sections and longitudinal-sections of the harvested regenerative nerve indicated that regenerative nerve fibers had been formed and accompanied with new blood vessels and matrix materials in the conduits. TEM images also showed that lots of fresh myelinated and non-myelinated nerve fibers had been formed. Parts of vacuolar, swollen and abnormal axons occurred in CSC and CSSC groups, while the vacuolization and swell of axons was the least serious in CSSPC group. These results indicated that CSSPC group had the most ability to repair and reconstruct the nerve structure and functions due to the comprehensive contributions from hollow CSC tube, SCs and PQQ. As a result, the CSSPC may have the potential for the applications as nerve guide

  10. Neural-Competent Cells of Adult Human Dermis Belong to the Schwann Lineage

    Science.gov (United States)

    Etxaniz, Usue; Pérez-San Vicente, Adrián; Gago-López, Nuria; García-Dominguez, Mario; Iribar, Haizea; Aduriz, Ariane; Pérez-López, Virginia; Burgoa, Izaskun; Irizar, Haritz; Muñoz-Culla, Maider; Vallejo-Illarramendi, Ainara; Leis, Olatz; Matheu, Ander; Martín, Angel G.; Otaegui, David; López-Mato, María Paz; Gutiérrez-Rivera, Araika; MacLellan, Robb; Izeta, Ander

    2014-01-01

    Summary Resident neural precursor cells (NPCs) have been reported for a number of adult tissues. Understanding their physiological function or, alternatively, their activation after tissue damage or in vitro manipulation remains an unsolved issue. Here, we investigated the source of human dermal NPCs in adult tissue. By following an unbiased, comprehensive approach employing cell-surface marker screening, cell separation, transcriptomic characterization, and in vivo fate analyses, we found that p75NTR+ precursors of human foreskin can be ascribed to the Schwann (CD56+) and perivascular (CD56−) cell lineages. Moreover, neural differentiation potential was restricted to the p75NTR+CD56+ Schwann cells and mediated by SOX2 expression levels. Double-positive NPCs were similarly obtained from human cardiospheres, indicating that this phenomenon might be widespread. PMID:25418723

  11. Neural-Competent Cells of Adult Human Dermis Belong to the Schwann Lineage

    Directory of Open Access Journals (Sweden)

    Usue Etxaniz

    2014-11-01

    Full Text Available Resident neural precursor cells (NPCs have been reported for a number of adult tissues. Understanding their physiological function or, alternatively, their activation after tissue damage or in vitro manipulation remains an unsolved issue. Here, we investigated the source of human dermal NPCs in adult tissue. By following an unbiased, comprehensive approach employing cell-surface marker screening, cell separation, transcriptomic characterization, and in vivo fate analyses, we found that p75NTR+ precursors of human foreskin can be ascribed to the Schwann (CD56+ and perivascular (CD56− cell lineages. Moreover, neural differentiation potential was restricted to the p75NTR+CD56+ Schwann cells and mediated by SOX2 expression levels. Double-positive NPCs were similarly obtained from human cardiospheres, indicating that this phenomenon might be widespread.

  12. Neural-competent cells of adult human dermis belong to the Schwann lineage.

    Science.gov (United States)

    Etxaniz, Usue; Pérez-San Vicente, Adrián; Gago-López, Nuria; García-Dominguez, Mario; Iribar, Haizea; Aduriz, Ariane; Pérez-López, Virginia; Burgoa, Izaskun; Irizar, Haritz; Muñoz-Culla, Maider; Vallejo-Illarramendi, Ainara; Leis, Olatz; Matheu, Ander; Martín, Angel G; Otaegui, David; López-Mato, María Paz; Gutiérrez-Rivera, Araika; MacLellan, Robb; Izeta, Ander

    2014-11-11

    Resident neural precursor cells (NPCs) have been reported for a number of adult tissues. Understanding their physiological function or, alternatively, their activation after tissue damage or in vitro manipulation remains an unsolved issue. Here, we investigated the source of human dermal NPCs in adult tissue. By following an unbiased, comprehensive approach employing cell-surface marker screening, cell separation, transcriptomic characterization, and in vivo fate analyses, we found that p75NTR(+) precursors of human foreskin can be ascribed to the Schwann (CD56(+)) and perivascular (CD56(-)) cell lineages. Moreover, neural differentiation potential was restricted to the p75NTR(+)CD56(+) Schwann cells and mediated by SOX2 expression levels. Double-positive NPCs were similarly obtained from human cardiospheres, indicating that this phenomenon might be widespread.

  13. 干细胞:许旺细胞的新来源%Derivation of Schwann cells from stem cells

    Institute of Scientific and Technical Information of China (English)

    赵安东; 蔡飒; 吕艳思; 潘宇; 林慧婷

    2012-01-01

    BACKGROUND: Schwann cells play an important role in the recovery and regeneration of peripheral nervous system (PNS) injury. However, Schwann cells are not easy to obtain directly which lead the limitation on clinical application. OBJECTIVE: To review the effect of Schwann cells on nervous system injury and regeneration process, and the potency of other stem cells to differentiate into Schwann cells. METHODS: A computer-based research on the Pubmed database was conducted to search the articles on Schwann cells participat ing in the regeneration of nervous system injury and the identification and application of Schwann cells differentiated from other stem cells, the key words were “Schwann cells, nervous system, stem cells”. The repetitive articles were eliminated; each articles and quotations were reviewed during the process of preliminary examination. A total of 29 articles were included acco rding to the inclusion criteria. RESULTS AND CONCLUSION: Schwann cells provide a suitable microenvironment for repair and regeneration through the secretion of various cytokines and trophic factors, thereby promote the axonal regeneration. Meanwhile, they can grow around the newborn axons and form the myelin through the mechanism of proliferation and differentiation. A large number of Schwann cells are required to repair the nervous system, but Schwann cells are not easy to directly obtain. Variety of stem cells, including embryonic stem cells, mesenchymal stem cells, neural crest stem cells and olfactory ensheathing cells can be induced to differentiate into Schwann cell- like cells in certain condi tions which provide new hope for the treatment of nervous system injury. Among them, the researches on the mesenchymal stem cells attract the most attention.%背景:许旺细胞对神经系统损伤的修复与再生有着重要作用.然而,许旺细胞不易直接获取,使其在临床上的应用受到限制.目的:综述神经损伤及修复过程、许旺细胞的作

  14. Platelet-rich plasma gel in combination with Schwann cells for repair of sciatic nerve injury

    Institute of Scientific and Technical Information of China (English)

    Fagang Ye; Haiyan Li; Guangxi Qiao; Feng Chen; Hao Tao; Aiyu Ji; Yanling Hu

    2012-01-01

    Bone marrow mesenchymal stem cells were isolated from New Zealand white rabbits,culture-expanded and differentiated into Schwann cell-like cells.Autologous platelet-rich plasma and Schwann cell-like cells were mixed in suspension at a density of 1 × 106 cells/mL,prior to introduction into a poly (lactic-co-glycolic acid) conduit.Fabricated tissue-engineered nerves were implanted into rabbits to bridge 10 mm sciatic nerve defects (platelet-rich plasma group).Controls were established using fibrin as the seeding matrix for Schwann cell-like cells at identical density to construct tissue-engineered nerves (fibrin group).Twelve weeks after implantation,toluidine blue staining and scanning electron microscopy were used to demonstrate an increase in the number of regenerating nerve fibers and thickness of the myelin sheath in the platelet-rich plasma group compared with the fibrin group.Fluoro-gold retrograde labeling revealed that the number of Fluoro-gold-positive neurons in the dorsal root ganglion and the spinal cord anterior horn was greater in the platelet-rich plasma group than in the fibrin group.Electrophysiological examination confirmed that compound muscle action potential and nerve conduction velocity were superior in the platelet-rich plasma group compared with the fibrin group.These results indicate that autologous platelet-rich plasma gel can effectively serve as a seeding matrix for Schwann cell-like cells to construct tissue-engineered nerves to promote peripheral nerve regeneration.

  15. Construction of nerve guide conduits from cellulose/soy protein composite membranes combined with Schwann cells and pyrroloquinoline quinone for the repair of peripheral nerve defect.

    Science.gov (United States)

    Luo, Lihua; Gan, Li; Liu, Yongming; Tian, Weiqun; Tong, Zan; Wang, Xiong; Huselstein, Celine; Chen, Yun

    2015-02-20

    Regeneration and functional reconstruction of peripheral nerve defects remained a significant clinical challenge. Nerve guide conduits, with seed cells or neurotrophic factors (NTFs), had been widely used to improve the repair and regeneration of injured peripheral nerve. Pyrroloquinoline quinone (PQQ) was an antioxidant that can stimulate nerve growth factors (NGFs) synthesis and accelerate the Schwann cells (SCs) proliferation and growth. In present study, three kinds of nerve guide conduits were constructed: one from cellulose/SPI hollow tube (CSC), another from CSC combined with SCs (CSSC), and the third one from CSSC combined with PQQ (CSSPC), respectively. And then they were applied to bridge and repair the sciatic nerve defect in rats, using autograft as control. Effects of different nerve guide conduits on the nerve regeneration were comparatively evaluated by general analysis, sciatic function index (SFI) and histological analysis (HE and TEM). Newly-formed regenerative nerve fibers were observed and running through the transparent nerve guide conduits 12 weeks after surgery. SFI results indicated that the reconstruction of motor function in CSSPC group was better than that in CSSC and CSC groups. HE images from the cross-sections and longitudinal-sections of the harvested regenerative nerve indicated that regenerative nerve fibers had been formed and accompanied with new blood vessels and matrix materials in the conduits. TEM images also showed that lots of fresh myelinated and non-myelinated nerve fibers had been formed. Parts of vacuolar, swollen and abnormal axons occurred in CSC and CSSC groups, while the vacuolization and swell of axons was the least serious in CSSPC group. These results indicated that CSSPC group had the most ability to repair and reconstruct the nerve structure and functions due to the comprehensive contributions from hollow CSC tube, SCs and PQQ. As a result, the CSSPC may have the potential for the applications as nerve guide

  16. The influence of electrospun fibre size on Schwann cell behaviour and axonal outgrowth

    Energy Technology Data Exchange (ETDEWEB)

    Gnavi, S., E-mail: sara.gnavi@unito.it [Department of Clinical and Biological Sciences, University of Torino, Orbassano 10043 (Italy); Neuroscience Institute of the Cavalieri-Ottolenghi Foundation, University of Torino, Orbassano 10043 (Italy); Fornasari, B.E., E-mail: benedettaelena.fornasari@unito.it [Department of Clinical and Biological Sciences, University of Torino, Orbassano 10043 (Italy); Neuroscience Institute of the Cavalieri-Ottolenghi Foundation, University of Torino, Orbassano 10043 (Italy); Tonda-Turo, C., E-mail: chiara.tondaturo@polito.it [Politecnico di Torino, Department of Mechanical and Aerospace Engineering, Politecnico of Torino, Torino 10100 (Italy); Ciardelli, G., E-mail: gianluca.ciardelli@polito.it [Politecnico di Torino, Department of Mechanical and Aerospace Engineering, Politecnico of Torino, Torino 10100 (Italy); CNR-IPCF UOS, Pisa 56124 (Italy); Zanetti, M., E-mail: marco.zanetti@unito.it [Nanostructured Interfaces and Surfaces, Department of Chemistry, University of Torino, Torino 10100 (Italy); Geuna, S., E-mail: stefano.geuna@unito.it [Department of Clinical and Biological Sciences, University of Torino, Orbassano 10043 (Italy); Neuroscience Institute of the Cavalieri-Ottolenghi Foundation, University of Torino, Orbassano 10043 (Italy); Perroteau, I., E-mail: isabelle.perroteau@unito.it [Department of Clinical and Biological Sciences, University of Torino, Orbassano 10043 (Italy)

    2015-03-01

    Fibrous substrates functioning as temporary extracellular matrices can be prepared easily by electrospinning, yielding fibrous matrices suitable as internal fillers for nerve guidance channels. In this study, gelatin micro- or nano-fibres were prepared by electrospinning by tuning the gelatin concentration and solution flow rate. The effect of gelatin fibre diameter on cell adhesion and proliferation was tested in vitro using explant cultures of Schwann cells (SC) and dorsal root ganglia (DRG). Cell adhesion was assessed by quantifying the cell spreading area, actin cytoskeleton organization and focal adhesion complex formation. Nano-fibres promoted cell spreading and actin cytoskeleton organization, increasing cellular adhesion and the proliferation rate. However, both migration rate and motility, quantified by transwell and time lapse assays respectively, were greater in cells cultured on micro-fibres. Finally, there was more DRG axon outgrowth on micro-fibres. These data suggest that the topography of electrospun gelatin fibres can be adjusted to modulate SC and axon organization and that both nano- and micro-fibres are promising fillers for the design of devices for peripheral nerve repair. - Highlights: • Electrospinning used to produce gelatin nano- and micro-fibre matrices. • Nano-fibre matrices promote Schwann cell organization and increase proliferation rate. • Micro-fibre matrices promote Schwann cell migration. • Micro-fibre matrices promote axonal outgrowth.

  17. A role for neuropilins in the interaction between Schwann cells and meningeal cells.

    Directory of Open Access Journals (Sweden)

    Kasper C D Roet

    Full Text Available In their natural habitat, the peripheral nerve, Schwann cells (SCs form nicely aligned pathways (also known as the bands of Büngner that guide regenerating axons to their targets. Schwann cells that are implanted in the lesioned spinal cord fail to align in pathways that could support axon growth but form cellular clusters that exhibit only limited intermingling with the astrocytes and meningeal cells (MCs that are present in the neural scar. The formation of cell clusters can be studied in co-cultures of SCs and MCs. In these co-cultures SCs form cluster-like non-overlapping cell aggregates with well-defined boundaries. There are several indications that neuropilins (NRPs play an important role in MC-induced SC aggregation. Both SCs and MCs express NRP1 and NRP2 and SCs express the NRP ligands Sema3B, C and E while MCs express Sema3A, C, E and F. We now demonstrate that in SC-MC co-cultures, siRNA mediated knockdown of NRP2 in SCs decreased the formation of SC clusters while these SCs maintained their capacity to align in bands of Büngner-like columnar arrays. Unexpectedly, knockdown of NRP1 expression resulted in a significant increase in SC aggregation. These results suggest that a reduction in NRP2 expression may enhance the capacity of implanted SCs to interact with MCs that invade a neural scar formed after a lesion of the spinal cord.

  18. [Phenotypic plasticity of neural crest-derived melanocytes and Schwann cells].

    Science.gov (United States)

    Dupin, Elisabeth

    2011-01-01

    Melanocytes, the pigmented cells of the skin, and the glial Schwann cells lining peripheral nerves are developmentally derived from an early and transient ectodermal structure of the vertebrate embryo, the neural crest, which is also at the origin of multiple neural and non-neural cell types. Besides melanocytes and neural cells of the peripheral nervous system, the neural crest cells give rise to mesenchymal cell types in the head, which form most of the craniofacial skeleton, dermis, fat tissue and vascular musculo-connective components. How such a wide diversity of differentiation fates is established during embryogenesis and is later maintained in adult tissues are among key questions in developmental and stem cell biology. The analysis of the developmental potentials of single neural crest cells cultured in vitro led to characterizing multipotent stem/progenitor cells as well as more restricted precursors in the early neural crest of avian and mammalian embryos. Data support a hierarchical model of the diversification of neural crest lineages through progressive restrictions of multipotent stem cell potentials driven by local environmental factors. In particular, melanocytes and glial Schwann cells were shown to arise from a common bipotent progenitor, which depends upon the peptide endothelin-3 for proliferation and self-renewal ability. In vivo, signaling by endothelin-3 and its receptor is also required for the early development of melanocytes and proper pigmentation of the vertebrate body. It is generally assumed that, after lineage specification and terminal differentiation, specialized cell types, like the melanocytes and Schwann cells, do not change their identity. However, this classic notion that somatic cell differentiation is a stable and irreversible process has been challenged by emerging evidence that dedifferentiation can occur in different biological systems through nuclear transfer, cell fusion, epigenetic modifications and ectopic gene

  19. MAL Overexpression Leads to Disturbed Expression of Genes That Influence Cytoskeletal Organization and Differentiation of Schwann Cells

    Directory of Open Access Journals (Sweden)

    Daniela Schmid

    2014-09-01

    Full Text Available In the developing peripheral nervous system, a coordinated reciprocal signaling between Schwann cells and axons is crucial for accurate myelination. The myelin and lymphocyte protein MAL is a component of lipid rafts that is important for targeting proteins and lipids to distinct domains. MAL overexpression impedes peripheral myelinogenesis, which is evident by a delayed onset of myelination and reduced expression of the myelin protein zero (Mpz/P0 and the low-affinity neurotrophin receptor p75NTR . This study shows that MAL overexpression leads to a significant reduction of Mpz and p75NTR expression in primary mouse Schwann cell cultures, which was already evident before differentiation, implicating an effect of MAL in early Schwann cell development. Their transcription was robustly reduced, despite normal expression of essential transcription factors and receptors. Further, the cAMP response element-binding protein (CREB and phosphoinositide 3-kinase signaling pathways important for Schwann cell differentiation were correctly induced, highlighting that other so far unknown rate limiting factors do exist. We identified novel genes expressed by Schwann cells in a MAL-dependent manner in vivo and in vitro. A number of those, including S100a4, RhoU and Krt23, are implicated in cytoskeletal organization and plasma membrane dynamics. We showed that S100a4 is predominantly expressed by nonmyelinating Schwann cells, whereas RhoU was localized within myelin membranes, and Krt23 was detected in nonmyelinating as well as in myelinating Schwann cells. Their differential expression during early peripheral nerve development further underlines their possible role in influencing Schwann cell differentiation and myelination.

  20. Sox2 expression in Schwann cells inhibits myelination in vivo and induces influx of macrophages to the nerve.

    Science.gov (United States)

    Roberts, Sheridan L; Dun, Xin-Peng; Doddrell, Robin D S; Mindos, Thomas; Drake, Louisa K; Onaitis, Mark W; Florio, Francesca; Quattrini, Angelo; Lloyd, Alison C; D'Antonio, Maurizio; Parkinson, David B

    2017-09-01

    Correct myelination is crucial for the function of the peripheral nervous system. Both positive and negative regulators within the axon and Schwann cell function to ensure the correct onset and progression of myelination during both development and following peripheral nerve injury and repair. The Sox2 transcription factor is well known for its roles in the development and maintenance of progenitor and stem cell populations, but has also been proposed in vitro as a negative regulator of myelination in Schwann cells. We wished to test fully whether Sox2 regulates myelination in vivo and show here that, in mice, sustained Sox2 expression in vivo blocks myelination in the peripheral nerves and maintains Schwann cells in a proliferative non-differentiated state, which is also associated with increased inflammation within the nerve. The plasticity of Schwann cells allows them to re-myelinate regenerated axons following injury and we show that re-myelination is also blocked by Sox2 expression in Schwann cells. These findings identify Sox2 as a physiological regulator of Schwann cell myelination in vivo and its potential to play a role in disorders of myelination in the peripheral nervous system. © 2017. Published by The Company of Biologists Ltd.

  1. Cooperative roles of BDNF expression in neurons and Schwann cells are modulated by exercise to facilitate nerve regeneration.

    Science.gov (United States)

    Wilhelm, Jennifer C; Xu, Mei; Cucoranu, Delia; Chmielewski, Sarah; Holmes, Tiffany; Lau, Kelly Shukkwan; Bassell, Gary J; English, Arthur W

    2012-04-04

    After peripheral nerve injury, neurotrophins play a key role in the regeneration of damaged axons that can be augmented by exercise, although the distinct roles played by neurons and Schwann cells are unclear. In this study, we evaluated the requirement for the neurotrophin, brain-derived neurotrophic factor (BDNF), in neurons and Schwann cells for the regeneration of peripheral axons after injury. Common fibular or tibial nerves in thy-1-YFP-H mice were cut bilaterally and repaired using a graft of the same nerve from transgenic mice lacking BDNF in Schwann cells (BDNF(-/-)) or wild-type mice (WT). Two weeks postrepair, axonal regeneration into BDNF(-/-) grafts was markedly less than WT grafts, emphasizing the importance of Schwann cell BDNF. Nerve regeneration was enhanced by treadmill training posttransection, regardless of the BDNF content of the nerve graft. We further tested the hypothesis that training-induced increases in BDNF in neurons allow regenerating axons to overcome a lack of BDNF expression in cells in the pathway through which they regenerate. Nerves in mice lacking BDNF in YFP(+) neurons (SLICK) were cut and repaired with BDNF(-/-) and WT nerves. SLICK axons lacking BDNF did not regenerate into grafts lacking Schwann cell BDNF. Treadmill training could not rescue the regeneration into BDNF(-/-) grafts if the neurons also lacked BDNF. Both Schwann cell- and neuron-derived BDNF are thus important for axon regeneration in cut peripheral nerves.

  2. Schwann cell coculture improves the therapeutic effect of bone marrow stromal cells on recovery in spinal cord-injured mice.

    Science.gov (United States)

    Xu, Xiaoyun; Geremia, Nicole; Bao, Feng; Pniak, Anna; Rossoni, Melissa; Brown, Arthur

    2011-01-01

    Studies of bone marrow stromal cells (MSCs) transplanted into the spinal cord-injured rat give mixed results: some groups report improved locomotor recovery while others only demonstrate improved histological appearance of the lesion. These studies show no clear correlation between neurological improvements and MSC survival. We examined whether MSC survival in the injured spinal cord could be enhanced by closely matching donor and recipient mice for genetic background and marker gene expression and whether exposure of MSCs to a neural environment (Schwann cells) prior to transplantation would improve their survival or therapeutic effects. Mice underwent a clip compression spinal cord injury at the fourth thoracic level and cell transplantation 7 days later. Despite genetic matching of donors and recipients, MSC survival in the injured spinal cord was very poor (∼1%). However, we noted improved locomotor recovery accompanied by improved histopathological appearance of the lesion in mice receiving MSC grafts. These mice had more white and gray matter sparing, laminin expression, Schwann cell infiltration, and preservation of neurofilament and 5-HT-positive fibers at and below the lesion. There was also decreased collagen and chondroitin sulphate proteoglycan deposition in the scar and macrophage activation in mice that received the MSC grafts. The Schwann cell cocultured MSCs had greater effects than untreated MSCs on all these indices of recovery. Analyses of chemokine and cytokine expression revealed that MSC/Schwann cell cocultures produced far less MCP-1 and IL-6 than MSCs or Schwann cells cultured alone. Thus, transplanted MSCs may improve recovery in spinal cord-injured mice through immunosuppressive effects that can be enhanced by a Schwann cell coculturing step. These results indicate that the temporary presence of MSCs in the injured cord is sufficient to alter the cascade of pathological events that normally occurs after spinal cord injury, generating a

  3. pSVPoMcat modifying Schwann cell to protect injured spinal neurons in rats

    Institute of Scientific and Technical Information of China (English)

    陈礼刚; 高立达; 等

    2002-01-01

    Objective:To investigate the protective effect of pSVPoMcat(myelin basic protein microgene)modifying Schwann cell on injured spinal neurons.Methods;A model of rat spinal cord injured by hemisection was used.One hundred and twenty healthy SD rats of both sexes weighing 250-300g were divided into three groups:GroupA(n=40,treated with implantation of pSPVoMcat modifying Schwann cell),GroupB(n=40,treated with implantation of Schwann cell only)and GroupC(n=400,treated with sham operation as the control).One week after operation the rat functional recovery was observed dynamically by using combined behavioral score(CBS)and cortical somatasensory evoked potentials,the spinal cord sections were stained by Nissl,acid phosphatase enzyme histochemistry and cell apoptosis was examined by metye green,terminal deoxynucleotidyl and the dUTP Nick end labeling technique.Quantitative analysis was done by computer image analysis system.Results:In Group A the injured neurons recovered well morphologically.The imaging analysis showed a result of GroupA>GroupB>Group Cin the size of the neurons (P<0.01),The percentage of ACP(acid phosphatase) stained area and the rate of apoptosis sequence were groupsASchwann cell implantation has protective effect on injured spinal neurons and promotes recovery of injured spinal cord function in rats.

  4. Dicer in Schwann cells is required for myelination and axonal integrity

    DEFF Research Database (Denmark)

    Pereira, Jorge A.; Baumann, Reto; Norrmén, Camilla

    2010-01-01

    Dicer is responsible for the generation of mature micro-RNAs (miRNAs) and loading them into RNA-induced silencing complex (RISC). RISC functions as a probe that targets mRNAs leading to translational suppression and mRNA degradation. Schwann cells (SCs) in the peripheral nervous system undergo...... and fail to start forming myelin. At the molecular level, the promyelinating transcription factor Krox20 and several myelin proteins [including myelin associated glycoprotein (MAG) and PMP22] were strongly reduced in mutant sciatic nerves. In contrast, the myelination inhibitors SOX2, Notch1, and Hes1 were......, we also found signs of axonal degeneration in Dicer mutant mice. Thus, our data indicate that miRNAs critically regulate Schwann cell gene expression that is required for myelination and to maintain axons via axon-glia interactions....

  5. The Proliferation Enhancing Effects of Salidroside on Schwann Cells In Vitro

    OpenAIRE

    Hui Liu; Peizhen Lv; Huayu Wu; Kun Zhang; Fuben Xu; Li Zheng; Jinmin Zhao

    2017-01-01

    Derived from Rhodiola rosea L., which is a popular plant in Eastern Europe and Asia, salidroside has pharmacological properties including antiviral, anticancer, hepatoprotective, antidiabetic, and antioxidative effects. Recent studies show that salidroside has neurotrophic and neuroprotective effects. However, the effect of salidroside on Schwann cells (SCs) and the underlying mechanisms of the salidroside-induced neurotrophin secretion have seldom been studied. In this study, the effect of s...

  6. Low-grade Schwann cell neoplasms with leptomeningeal dissemination: clinicopathologic and autopsy findings.

    Science.gov (United States)

    Rodriguez, Erika F; Blakeley, Jaishri; Langmead, Shannon; Olivi, Alessandro; Tufaro, Anthony; Tabbarah, Abeer; Berkenblit, Gail; Sacks, Justin M; Newsome, Scott D; Montgomery, Elizabeth; Rodriguez, Fausto J

    2017-02-01

    Leptomeningeal dissemination of low-grade Schwann cell neoplasms is an exceptionally rare occurrence and has not been well documented in the literature. We encountered 2 cases of leptomeningeal dissemination of low-grade Schwann cell neoplasms. Patient 1 was a 63-year-old woman with neurofibromatosis type 1 and a progressive low-grade malignant peripheral nerve sheath tumor developing from a diffuse/plexiform orbital neurofibroma that arose in childhood. The neoplasm demonstrated local and leptomeningeal dissemination intracranially leading to the patient's death. There was partial loss of H3K27 tri-methylation, p16 and collagen IV. Patient 2 was a 60-year-old man without neurofibromatosis type 1 who presented with cranial nerve symptoms and a disseminated neoplasm with a Schwann cell phenotype. The neoplasm stabilized after irradiation and chemotherapy, but the patient died of medical complications. Autopsy findings documented disseminated leptomeningeal disease in the intracranial and spinal compartment. H3K27M tri-methylation was preserved. The clinicopathologic and autopsy findings are studied and presented, and the literature is reviewed.

  7. BACE1 regulates the proliferation and cellular functions of Schwann cells.

    Science.gov (United States)

    Hu, Xiangyou; Hou, Hailong; Bastian, Chinthasagar; He, Wanxia; Qiu, Shupeng; Ge, Yingying; Yin, Xinhua; Kidd, Grahame J; Brunet, Sylvain; Trapp, Bruce D; Baltan, Selva; Yan, Riqiang

    2017-05-01

    BACE1 is an indispensable enzyme for generating β-amyloid peptides, which are excessively accumulated in brains of Alzheimer's patients. However, BACE1 is also required for proper myelination of peripheral nerves, as BACE1-null mice display hypomyelination. To determine the precise effects of BACE1 on myelination, here we have uncovered a role of BACE1 in the control of Schwann cell proliferation during development. We demonstrate that BACE1 regulates the cleavage of Jagged-1 and Delta-1, two membrane-bound ligands of Notch. BACE1 deficiency induces elevated Jag-Notch signaling activity, which in turn facilitates proliferation of Schwann cells. This increase in proliferation leads to shortened internodes and decreased Schmidt-Lanterman incisures. Functionally, evoked compound action potentials in BACE1-null nerves were significantly smaller and slower, with a clear decrease in excitability. BACE1-null nerves failed to effectively use lactate as an alternative energy source under conditions of increased physiological activity. Correlatively, BACE1-null mice showed reduced performance on rotarod tests. Collectively, our data suggest that BACE1 deficiency enhances proliferation of Schwann cell due to the elevated Jag1/Delta1-Notch signaling, but fails to myelinate axons efficiently due to impaired the neuregulin1-ErbB signaling, which has been documented.

  8. Oriented growth and transdifferentiation of mesenchymal stem cells towards a Schwann cell fate on micropatterned substrates.

    Science.gov (United States)

    Sharma, Anup D; Zbarska, Svitlana; Petersen, Emma M; Marti, Mustafa E; Mallapragada, Surya K; Sakaguchi, Donald S

    2016-03-01

    While Schwann cells (SCs) have a significant role in peripheral nerve regeneration, their use in treatments has been limited because of lack of a readily available source. To address this issue, this study focused on the effect of guidance cues by employing micropatterned polymeric films to influence the alignment, morphology and transdifferentiation of bone marrow-derived rat mesenchymal stem cells (MSCs) towards a Schwann cell-like fate. Two different types of polymers, biocompatible polystyrene (PS) and biodegradable poly(lactic acid) (PLA) were used to fabricate patterned films. Percentages of transdifferentiated MSCs (tMSCs) immunolabeled with SC markers (α-S100β and α-p75(NTR)) were found to be similar on patterned versus smooth PS and PLA substrates. However, patterning had a significant effect on the alignment and elongation of the tMSCs. More than 80% of the tMSCs were oriented in the direction of microgrooves (0°-20°), while cells on the smooth substrates were randomly oriented. The aspect ratio [AR, ratio of length (in direction of microgrooves) and breadth (in direction perpendicular to microgrooves)] of the tMSCs on patterned substrates had a value of approximately five, as compared to cells on smooth substrates where the AR was one. Understanding responses to these cues in vitro helps us in understanding the behavior and interaction of the cells with the 3D environment of the scaffolds, facilitating the application of these concepts to designing effective nerve guidance conduits for peripheral nerve regeneration.

  9. Tuning the Mechanical Properties of Poly(Ethylene Glycol) Microgel-Based Scaffolds to Increase 3D Schwann Cell Proliferation.

    Science.gov (United States)

    Zhou, Wenda; Stukel, Jessica M; Cebull, Hannah L; Willits, Rebecca Kuntz

    2016-04-01

    2D in vitro studies have demonstrated that Schwann cells prefer scaffolds with mechanical modulus approximately 10× higher than the modulus preferred by nerves, limiting the ability of many scaffolds to promote both neuron extension and Schwann cell proliferation. Therefore, the goals of this work are to develop and characterize microgel-based scaffolds that are tuned over the stiffness range relevant to neural tissue engineering and investigate Schwann cell morphology, viability, and proliferation within 3D scaffolds. Using thiol-ene reaction, microgels with surface thiols are produced and crosslinked into hydrogels using a multiarm vinylsulfone (VS). By varying the concentration of VS, scaffold stiffness ranges from 0.13 to 0.76 kPa. Cell morphology in all groups demonstrates that cells are able to spread and interact with the scaffold through day 5. Although the viability in all groups is high, proliferation of Schwann cells within the scaffold of G* = 0.53 kPa is significantly higher than other groups. This result is ≈ 5× lower than previously reported optimal stiffnesses on 2D surfaces, demonstrating the need for correlation of 3D cell response to mechanical modulus. As proliferation is the first step in Schwann cell integration into peripheral nerve conduits, these scaffolds demonstrate that the stiffness is a critical parameter to optimizing the regenerative process.

  10. Effects of cotransplantated Schwann cells and neural stem cells in a rat model of Alzheimer's disease

    Institute of Scientific and Technical Information of China (English)

    Yan Zhan; Dihui Ma; Yu Zhang

    2011-01-01

    Schwann cells (SCs) are significantly better at promoting neural stem cell (NSCs) proliferation, differentiation and synaptic formation when cocultured with NSCs in vitro, compared with cultured in a single nerve growth factor. The present study transplanted NSCs and SCs into the brain of a rat model of Alzheimer's disease to investigate the effect of cotransplantation. Results show transplantation of both NSCs alone and NSCs + SCs significantly promoted learning and memory functions in Alzheimer's disease rats, decreased glial fibrillary acidic protein and calcium binding protein S100β expression, but increased expression of the cholinergic neuron marker choline acetyl transferase mRNA. The effect of NSCs + SCs cotransplantation was, however, more significant. NSCs and SCs cotransplantation significantly reduced the number of astrocytes and increased cholinergic neurons, facilitating the recovery of learning and memory function, compared with NSCs transplantation alone.

  11. Axon-Schwann cell interactions during peripheral nerve regeneration in zebrafish larvae.

    Science.gov (United States)

    Ceci, Maria Laura; Mardones-Krsulovic, Camila; Sánchez, Mario; Valdivia, Leonardo E; Allende, Miguel L

    2014-10-17

    Peripheral nerve injuries can severely affect the way that animals perceive signals from the surrounding environment. While damage to peripheral axons generally has a better outcome than injuries to central nervous system axons, it is currently unknown how neurons re-establish their target innervations to recover function after injury, and how accessory cells contribute to this task. Here we use a simple technique to create reproducible and localized injury in the posterior lateral line (pLL) nerve of zebrafish and follow the fate of both neurons and Schwann cells. Using pLL single axon labeling by transient transgene expression, as well as transplantation of glial precursor cells in zebrafish larvae, we individualize different components in this system and characterize their cellular behaviors during the regenerative process. Neurectomy is followed by loss of Schwann cell differentiation markers that is reverted after nerve regrowth. We show that reinnervation of lateral line hair cells in neuromasts during pLL nerve regeneration is a highly dynamic process with promiscuous yet non-random target recognition. Furthermore, Schwann cells are required for directional extension and fasciculation of the regenerating nerve. We provide evidence that these cells and regrowing axons are mutually dependant during early stages of nerve regeneration in the pLL. The role of ErbB signaling in this context is also explored. The accessibility of the pLL nerve and the availability of transgenic lines that label this structure and their synaptic targets provides an outstanding in vivo model to study the different events associated with axonal extension, target reinnervation, and the complex cellular interactions between glial cells and injured axons during nerve regeneration.

  12. 轴突影响施万细胞分化与整合素α6β4表达%Axonal regulation of Schwann cell differentiation and integrin α6β4 expression

    Institute of Scientific and Technical Information of China (English)

    钟延丰; 任碧和; 王立军; 由江峰; 王盛兰; 王薇; 杨金辉; 胡白和

    2001-01-01

    Objective: To study the axonal effect and the expression of integrin α6β4 during Schwann cell(SC) differentiation and myelination. Methods: Schwann cells were dissociated from the sciatic nerve of neonatal Waster rats and neurons dissociated from spinal cord. Singal cultures and purified populations of SC were cocultured with NC. Four methods (contrast microscope, scanning electron microscopy(SEM), immunocytochemistry method and in situ hybridization ) were used. Results: The separately cultured Schwann cells showed MBP negetive by immunocytochemistry method. But cocultured SC were shown positive. SEM showed that Schwann cells' membrane loop progressively circumnavigated around the axon during myelination, which suggested that the non-myelinating SC(nMSC) transformed to myelinating SC (MSC). In situ hybridization showed integrin α6β4 positive signals only on the outer surface of the Schwann cell-axon unit in SC coculture with NC. Conclusion: The differentiation and maturation of SC depend on axon, and the activity of integrins is expressed by axon. Axonal contact induces the expression of α6β4 during SC myelination, which suggests that integrin α6β4 is an important mediator of interactions of myelinating SC with the basal limina.%目的:探讨轴突对施万细胞(Schwann cells, SC)分化成熟与髓鞘形成的影响,及在SC的极向分化过程中整合素α6β4的表达。方法:用Wistar乳鼠坐骨神经分离SC,用其脊髓分离神经细胞。经纯化后分别培养及共同培养。用扫描电镜观察二者的形态及髓鞘形成情况;分别用髓鞘碱性蛋白(myelin basic protein,MBP)、神经微丝(neurofilament,NF)抗体进行免疫标记;采用原位杂交技术检测整合素α6β4 mRNA的表达。结果:单独培养的SC MBP抗原表达阴性;原位杂交检测α6β4表达阴性。SC与神经细胞共同培养时其MBP阳性(说明其已转变为髓鞘形成细胞),在神经突起周围表达阳性;扫描电

  13. Adult skin-derived precursor Schwann cells exhibit superior myelination and regeneration supportive properties compared to chronically denervated nerve-derived Schwann cells.

    Science.gov (United States)

    Kumar, Ranjan; Sinha, Sarthak; Hagner, Andrew; Stykel, Morgan; Raharjo, Eko; Singh, Karun K; Midha, Rajiv; Biernaskie, Jeff

    2016-04-01

    Functional outcomes following delayed peripheral nerve repair are poor. Schwann cells (SCs) play key roles in supporting axonal regeneration and remyelination following nerve injury, thus understanding the impact of chronic denervation on SC function is critical toward developing therapies to enhance regeneration. To improve our understanding of SC function following acute versus chronic-denervation, we performed functional assays of SCs from adult rodent sciatic nerve with acute- (Day 5 post) or chronic-denervation (Day 56 post), versus embryonic nerves. We also compared Schwann cells derived from adult skin-derived precursors (aSKP-SCs) as an accessible, autologous alternative to supplement the distal (denervated) nerve. We found that acutely-injured SCs and aSKP-SCs exhibited superior proliferative capacity, promotion of neurite outgrowth and myelination of axons, both in vitro and following transplant into a sciatic nerve crush injury model, while chronically-denervated SCs were severely impaired. Acute injury caused re-activation of transcription factors associated with an immature and pro-myelinating SC state (Oct-6, cJun, Sox2, AP2α, cadherin-19), but was diminished with prolonged denervation in vivo and could not be rescued following expansion in vitro suggesting that this is a permanent deficiency. Interestingly, aSKP-SCs closely resembled acutely injured and embryonic SCs, exhibiting elevated expression of these same transcription factors. In summary, prolonged denervation resulted in SC deficiency in several functional parameters that may contribute to impaired regeneration. In contrast, aSKP-SCs closely resemble the regenerative attributes ascribed to acutely-denervated or embryonic SCs emphasizing their potential as an accessible and autologous source of glia cells to enhance nerve regeneration, particularly following delays to surgical repair. Copyright © 2016. Published by Elsevier Inc.

  14. Axonal outgrowth is associated with increased ERK 1/2 activation but decreased caspase 3 linked cell death in Schwann cells after immediate nerve repair in rats

    Directory of Open Access Journals (Sweden)

    Kanje Martin

    2011-01-01

    Full Text Available Abstract Background Extracellular-signal regulated kinase (ERK1/2 is activated by nerve damage and its activation precedes survival and proliferation of Schwann cells. In contrast, activation of caspase 3, a cysteine protease, is considered as a marker for apoptosis in Schwann cells. In the present study, axonal outgrowth, activation of ERK1/2 by phosphorylation (p-ERK 1/2 and immunoreactivity of cleaved caspase 3 were examined after immediate, delayed, or no repair of transected rat sciatic nerves. Results Axonal outgrowth, detected by neurofilament staining, was longer after immediate repair than after either the delayed or no repair conditions. Immediate repair also showed a higher expression of p-ERK 1/2 and a lower number of cleaved caspase 3 stained Schwann cells than after delayed nerve repair. If the transected nerve was not repaired a lower level of p-ERK 1/2 was found than in either the immediate or delayed repair conditions. Axonal outgrowth correlated to p-ERK 1/2, but not clearly with cleaved caspase 3. Contact with regenerating axons affected Schwann cells with respect to p-ERK 1/2 and cleaved caspase 3 after immediate nerve repair only. Conclusion The decreased regenerative capacity that has historically been observed after delayed nerve repair may be related to impaired activation of Schwann cells and increased Schwann cell death. Outgrowing axons influence ERK 1/2 activation and apoptosis of Schwann cells.

  15. Inter-microcarrier transfer and phenotypic stability of stem cell-derived Schwann cells in stirred suspension bioreactor culture.

    Science.gov (United States)

    Shakhbazau, Antos; Mirfeizi, Leila; Walsh, Tylor; Wobma, Holly M; Kumar, Ranjan; Singh, Bhagat; Kallos, Michael S; Midha, Rajiv

    2016-02-01

    Emerging bioreactor technologies offer an effective way for scaled-up production of large numbers of cells for cell therapy applications. One of the clinical paradigms where cell therapy can be an asset is restorative neurosciences. Nerve repair can benefit from the injections of stem cells and/or Schwann cells, acting as a source for axon myelination, myelin debris clearance, and trophic support. We have adapted microcarrier-based suspension bioreactor culture for Schwann cells (SCs) differentiated from a new stem cell source - skin-derived precursors (SKPs). SKP-derived SCs attach and grow on different types of microcarriers in both static and stirred culture, with Cytodex 3 and CultiSpher-S found most effective. Inter-microcarrier migration of SKP-SCs represents a key mechanism for rapid expansion and colonization in stirred suspension culture. We have shown that microcarrier-expanded SKP-SCs cells express Schwann cell markers p75-NTR, GFAP and S100 and retain their key ability to myelinate axons both in vitro and in vivo. Scaled-up microcarrier-based production of SKP-SCs in suspension bioreactors appears feasible for timely generation of sufficient cell numbers for nerve repair strategies.

  16. Spatiotemporal distribution and function of N-cadherin in postnatal Schwann cells: A matter of adhesion?

    DEFF Research Database (Denmark)

    Corell, Mikael; Wicher, Grzegorz; Limbach, Christoph;

    2010-01-01

    . In this study, we investigated the distribution of N-cadherin in the developing postnatal and adult rat peripheral nervous system. N-cadherin was found primarily in ensheathing glia throughout development, concentrated at neuron-glial or glial-glial contacts of the sciatic nerve, dorsal root ganglia (DRG......), and myenteric plexi. In the sciatic nerve, N-cadherin decreases with age and progress of myelination. In adult animals, N-cadherin was found exclusively in nonmyelinating Schwann cells. The distribution of N-cadherin in developing E17 DRG primary cultures is similar to what was observed in vivo. Functional...

  17. Essential and distinct roles for cdc42 and rac1 in the regulation of Schwann cell biology during peripheral nervous system development

    DEFF Research Database (Denmark)

    Benninger, Yves; Thurnherr, Tina; Pereira, Jorge A

    2007-01-01

    During peripheral nervous system (PNS) myelination, Schwann cells must interpret extracellular cues to sense their environment and regulate their intrinsic developmental program accordingly. The pathways and mechanisms involved in this process are only partially understood. We use tissue-specific......During peripheral nervous system (PNS) myelination, Schwann cells must interpret extracellular cues to sense their environment and regulate their intrinsic developmental program accordingly. The pathways and mechanisms involved in this process are only partially understood. We use tissue......-specific conditional gene targeting to show that members of the Rho GTPases, cdc42 and rac1, have different and essential roles in axon sorting by Schwann cells. Our results indicate that although cdc42 is required for normal Schwann cell proliferation, rac1 regulates Schwann cell process extension and stabilization...

  18. 3-D Imaging Reveals Participation of Donor Islet Schwann Cells and Pericytes in Islet Transplantation and Graft Neurovascular Regeneration

    Directory of Open Access Journals (Sweden)

    Jyuhn-Huarng Juang

    2015-02-01

    Full Text Available The primary cells that participate in islet transplantation are the endocrine cells. However, in the islet microenvironment, the endocrine cells are closely associated with the neurovascular tissues consisting of the Schwann cells and pericytes, which form sheaths/barriers at the islet exterior and interior borders. The two cell types have shown their plasticity in islet injury, but their roles in transplantation remain unclear. In this research, we applied 3-dimensional neurovascular histology with cell tracing to reveal the participation of Schwann cells and pericytes in mouse islet transplantation. Longitudinal studies of the grafts under the kidney capsule identify that the donor Schwann cells and pericytes re-associate with the engrafted islets at the peri-graft and perivascular domains, respectively, indicating their adaptability in transplantation. Based on the morphological proximity and cellular reactivity, we propose that the new islet microenvironment should include the peri-graft Schwann cell sheath and perivascular pericytes as an integral part of the new tissue.

  19. Novel three-dimensional nerve tissue engineering scaffolds and its biocompatibility with Schwann cells

    Institute of Scientific and Technical Information of China (English)

    YUAN Jian-dong; NIE Wen-bo; FU Qiang; LIAN Xiao-feng; HOU Tie-sheng; TAN Zhi-qing

    2009-01-01

    To develop a novel scaffolding method for the copolymers poly lactide-co-glycolide acid (PLGA) to construct a three-dimensional (3-D) scaffold and explore its biocompatibility through culturing Schwann cells (SCs) on it. Methods: The 3-D scaffolds were made by means of melt spinning, extension and weaving. The queueing disci-pline of the micro-channels were observed under a scan-ning electronic microscope (SEM).The sizes of the micropores and the factors of porosity were also measured. Sciatic nerves were harvested from 3-day-old Sprague Dawley (SD) rats for culture of SCs. SCs were separated, purified, and then implanted on PLGA scaffolds, gelatin sponge and poly-L-lysine (PLL)-coated tissue culture poly-styrene (TCPS) were used as biomaterial and cell-support-ive controls, respectively. The effect of PLGA on the adherence, proliferation and apoptosis of SCs were exam-ined in vitro in comparison with gelatin sponge and TCPS. Results: The micro-channels arrayed in parallel manners, and the pore sizes of the channels were uniform. No significant difference was found in the activity of Schwann cells cultured on PLEA and those on TCPS (P>0.05), and the DNA of PLGA scaffolds was not damaged. Conclusion: The 3-D scaffolds developed in this study have excellent structure and biocompatibility, which may be taken as a novel scaffold candidate for nerve-tissue engineering.

  20. The Proliferation Enhancing Effects of Salidroside on Schwann Cells In Vitro.

    Science.gov (United States)

    Liu, Hui; Lv, Peizhen; Wu, Huayu; Zhang, Kun; Xu, Fuben; Zheng, Li; Zhao, Jinmin

    2017-01-01

    Derived from Rhodiola rosea L., which is a popular plant in Eastern Europe and Asia, salidroside has pharmacological properties including antiviral, anticancer, hepatoprotective, antidiabetic, and antioxidative effects. Recent studies show that salidroside has neurotrophic and neuroprotective effects. However, the effect of salidroside on Schwann cells (SCs) and the underlying mechanisms of the salidroside-induced neurotrophin secretion have seldom been studied. In this study, the effect of salidroside on the survival, proliferation, and gene expression of Schwann cells lineage (RSC96) was studied through the examinations of the cell viability, proliferation, morphology, and expression of neurotrophic factor related genes including BDNF, GDNF, and CDNF at 2, 4, and 6 days, respectively. These results showed that salidroside significantly enhanced survival and proliferation of SCs. The underlying mechanism might involve that salidroside affected SCs growth through the modulation of several neurotrophic factors including BDNF, GDNF, and CDNF. As for the concentration, 0.4 mM, 0.2 mM, and 0.1 mM of salidroside were recommended, especially 0.2 mM. This investigation indicates that salidroside is capable of enhancing SCs survival and function in vitro, which highlights the possibility that salidroside as a drug agent to promote nerve regeneration in cellular nerve scaffold through salidroside-induced neurotrophin secretion in SCs.

  1. The Proliferation Enhancing Effects of Salidroside on Schwann Cells In Vitro

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    Hui Liu

    2017-01-01

    Full Text Available Derived from Rhodiola rosea L., which is a popular plant in Eastern Europe and Asia, salidroside has pharmacological properties including antiviral, anticancer, hepatoprotective, antidiabetic, and antioxidative effects. Recent studies show that salidroside has neurotrophic and neuroprotective effects. However, the effect of salidroside on Schwann cells (SCs and the underlying mechanisms of the salidroside-induced neurotrophin secretion have seldom been studied. In this study, the effect of salidroside on the survival, proliferation, and gene expression of Schwann cells lineage (RSC96 was studied through the examinations of the cell viability, proliferation, morphology, and expression of neurotrophic factor related genes including BDNF, GDNF, and CDNF at 2, 4, and 6 days, respectively. These results showed that salidroside significantly enhanced survival and proliferation of SCs. The underlying mechanism might involve that salidroside affected SCs growth through the modulation of several neurotrophic factors including BDNF, GDNF, and CDNF. As for the concentration, 0.4 mM, 0.2 mM, and 0.1 mM of salidroside were recommended, especially 0.2 mM. This investigation indicates that salidroside is capable of enhancing SCs survival and function in vitro, which highlights the possibility that salidroside as a drug agent to promote nerve regeneration in cellular nerve scaffold through salidroside-induced neurotrophin secretion in SCs.

  2. Histological observation on acellular nerve grafts co-cultured with Schwann cells for repairing defects of the sciatic nerve

    Institute of Scientific and Technical Information of China (English)

    Xiaohong Sun; Jiangyi Tian; Xiaojie Tong; Xu Zhang; Zheng He

    2006-01-01

    BACKGROUND: Animal experiments and clinical studies about tissue engineering method applied to repair nerve injury mainly focus on seeking ideal artificial nerve grafts, nerve conduit and seed cells. Autologous nerve, allogeneic nerve and xenogeneic nerve are used to bridge nerve defects, it is one of the methods to promote the repair of nerve injury by culturing and growing Schwann cells, which can secrete various neurotrophic factor activities, in the grafts.OBJECTIVE: To observe the effect of acellular nerve grafts co-cultured with Schwann cells in repairing defects of sciatic nerve.DESIGN: An observational comparative study.SETTING: Tissue Engineering Laboratory of China Medical University.MATERIALS: The experiment was carried out in the Tissue Engineering Laboratory of China Medical University between April 2004 and April 2005. Forty neonatal Sprague-Dawley rats of 5-8 days (either males or females) and 24 male Wistar rats of 180-220 g were provided by the experimental animal center of China Medical University.METHODS: ① Culture of Schwann cells: The bilateral sciatic nerves and branchial plexus were isolated from the 40 neonatal SD rats. The sciatic nerves were enzymatically digested with collagenase and dispase, isolatd, purified and cultured with the method of speed-difference adhersion, and identified with the SABC immunohistochemical method. ② Model establishment: In vitro Schwann cells were microinjected into 10-mm long acellular nerve grafts repairing a surgically created gap in the rat sciatic nerve.According to the different grafted methods, the animals were randomly divided into three groups: autografts (n=8), acellular nerve grafts (n=8), or acellular nerve grafts with Schwann cells (n=8). ③ The regenerated nerve fiber number and average diameter of myeline sheath after culture were statistically anlayzed.MAIN OUTCOME MEASURES: ① The regenerated nerve ultrastructure, total number and density of myelinated nerve fibers, and the thickness of

  3. Puerarin prevents high glucose-induced apoptosis of Schwann cells by inhibiting oxidative stress

    Institute of Scientific and Technical Information of China (English)

    Yingying Wu; Bing Xue; Xiaojin Li; Hongchen Liu

    2012-01-01

    Oxidative stress may be the unifying factor for the injury caused by hyperglycemia in diabeticperipheral neuropathy.Puerarin is the major isoflavonoid derived from Radix puerariae and has been shown to be effective in increasing superoxide dismutase activity.This study sought to investigate the neuroprotective effect of puerarin on high glucose-induced oxidative stress and Schwann cell apoptosis in vitro.Intracellular reactive oxygen radicals and mitochondrial transmembrane potential were detected by flow cytometry analysis.Apoptosis was confirmed by TUNEL and oxidative stress was monitored using an enzyme-linked immunosorbent assay for the DNA marker 8-hydroxy-2-deoxyguanosine.The expression levels of bax and bcl-2 were analyzed by quantitative real-time reverse transcriptase-PCR,while protein expression of cleaved caspase-3 and-9 were analyzed by means of western blotting.Results suggested that puerarin treatment inhibited high glucose-induced oxidative stress,mitochondrial depolarization and apoptosis in a dose-dependent manner.Furthermore,puerarin treatment downregulated Bax expression,upregulated bcl-2 expression and attenuated the activation of caspase-3 and-9.Overall,our results indicated that puerarin antagonized high glucose-induced oxidative stress and apoptosis in Schwann cells.

  4. Conditional Inactivation of Pten with EGFR Overexpression in Schwann Cells Models Sporadic MPNST

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    Vincent W. Keng

    2012-01-01

    Full Text Available The genetic mechanisms involved in the transformation from a benign neurofibroma to a malignant sarcoma in patients with neurofibromatosis-type-1- (NF1-associated or sporadic malignant peripheral nerve sheath tumors (MPNSTs remain unclear. It is hypothesized that many genetic changes are involved in transformation. Recently, it has been shown that both phosphatase and tensin homolog (PTEN and epidermal growth factor receptor (EGFR play important roles in the initiation of peripheral nerve sheath tumors (PNSTs. In human MPNSTs, PTEN expression is often reduced, while EGFR expression is often induced. We tested if these two genes cooperate in the evolution of PNSTs. Transgenic mice were generated carrying conditional floxed alleles of Pten, and EGFR was expressed under the control of the 2′,3′-cyclic nucleotide 3′phosphodiesterase (Cnp promoter and a desert hedgehog (Dhh regulatory element driving Cre recombinase transgenic mice (Dhh-Cre. Complete loss of Pten and EGFR overexpression in Schwann cells led to the development of high-grade PNSTs. In vitro experiments using immortalized human Schwann cells demonstrated that loss of PTEN and overexpression of EGFR cooperate to increase cellular proliferation and anchorage-independent colony formation. This mouse model can rapidly recapitulate PNST onset and progression to high-grade PNSTs, as seen in sporadic MPNST patients.

  5. A role of peripheral myelin protein 2 in lipid homeostasis of myelinating Schwann cells.

    Science.gov (United States)

    Zenker, Jennifer; Stettner, Mark; Ruskamo, Salla; Domènech-Estévez, Enric; Baloui, Hasna; Médard, Jean-Jacques; Verheijen, Mark H G; Brouwers, Jos F; Kursula, Petri; Kieseier, Bernd C; Chrast, Roman

    2014-09-01

    Peripheral myelin protein 2 (Pmp2, P2 or Fabp8), a member of the fatty acid binding protein family, was originally described together with myelin basic protein (Mbp or P1) and myelin protein zero (Mpz or P0) as one of the most abundant myelin proteins in the peripheral nervous system (PNS). Although Pmp2 is predominantly expressed in myelinated Schwann cells, its role in glia is currently unknown. To study its function in PNS biology, we have generated a complete Pmp2 knockout mouse (Pmp2(-/-) ). Comprehensive characterization of Pmp2(-/-) mice revealed a temporary reduction in their motor nerve conduction velocity (MNCV). While this change was not accompanied by any defects in general myelin structure, we detected transitory alterations in the myelin lipid profile of Pmp2(-/-) mice. It was previously proposed that Pmp2 and Mbp have comparable functions in the PNS suggesting that the presence of Mbp can partially mask the Pmp2(-/-) phenotype. Indeed, we found that Mbp lacking Shi(-/-) mice, similar to Pmp2(-/-) animals, have preserved myelin structure and reduced MNCV, but this phenotype was not aggravated in Pmp2(-/-) /Shi(-/-) mutants indicating that Pmp2 and Mbp do not substitute each other's functions in the PNS. These data, together with our observation that Pmp2 binds and transports fatty acids to membranes, uncover a role for Pmp2 in lipid homeostasis of myelinating Schwann cells.

  6. Protein expression profile in the differentiation of rat bone marrow stromal cells into Schwann cell-like cells

    Institute of Scientific and Technical Information of China (English)

    LI WenTing; SUN HuaLin; XU ZengLu; DING Fei; GU XiaoSong

    2009-01-01

    During the last decade, increasing evidence suggested that bone marrow stromal cells (MSCs) have the potential to differentiate into neural lineages. Many studies have reported that MSCs showed morpho-logical changes and expressed a limited number of neural proteins under experimental conditions. However, no proteomic studies on MSCs differentiated into Schwann cell-like cells have been reported. In this study, we isolated MSCs from adult Sprague-Dawley rat femur and tibia bone marrows and in-duced the cells in vitro under specific conditions. By using two-dimensional gel electrophoresis (2-DE), we compared the protein profiles of MSCs before and after induced differentiation. We obtained 792 protein spots in the protein profile by 2-DE, and found that 74 spots changed significantly before and after the differentiation using PDQuest software, with 43 up-regulated and 31 down-regulated. We ana-lyzed these 74 spots by a matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF-MS) and by database searching, and found that they could be grouped into various classes, including cytoskeleton and structure proteins, growth factors, metabolic proteins, chaperone proteins, receptor proteins, cell cycle proteins, calcium binding proteins, and other proteins. These proteins also include neural and glial proteins, such as BDNF, CNTF and GFAP. The results may provide valuable proteomic information about the differentiation of MSCs into Schwann cell-like cells.

  7. Protein expression profile in the differentiation of rat bone marrow stromal cells into Schwann cell-like cells

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    During the last decade,increasing evidence suggested that bone marrow stromal cells(MSCs) have the potential to differentiate into neural lineages.Many studies have reported that MSCs showed morphological changes and expressed a limited number of neural proteins under experimental conditions.However,no proteomic studies on MSCs differentiated into Schwann cell-like cells have been reported.In this study,we isolated MSCs from adult Sprague-Dawley rat femur and tibia bone marrows and induced the cells in vitro under specific conditions.By using two-dimensional gel electrophoresis(2-DE),we compared the protein profiles of MSCs before and after induced differentiation.We obtained 792 protein spots in the protein profile by 2-DE,and found that 74 spots changed significantly before and after the differentiation using PDQuest software,with 43 up-regulated and 31 down-regulated.We analyzed these 74 spots by a matrix assisted laser desorption ionization-time of flight mass spectrometry(MALDI-TOF-MS) and by database searching,and found that they could be grouped into various classes,including cytoskeleton and structure proteins,growth factors,metabolic proteins,chaperone proteins,receptor proteins,cell cycle proteins,calcium binding proteins,and other proteins.These proteins also include neural and glial proteins,such as BDNF,CNTF and GFAP.The results may provide valuable proteomic information about the differentiation of MSCs into Schwann cell-like cells.

  8. Distinctive effects of rat fibroblast growth factor-2 isoforms on PC12 and Schwann cells.

    Science.gov (United States)

    Müller-Ostermeyer, F; Claus, P; Grothe, C

    2001-01-01

    Fibroblast growth factor-2 (FGF-2) is an important modulator of cell growth and differentiation and stimulates cell survival of various cells including neurons. Rat FGF-2 occurs in three isoforms, a low molecular weight 18 kD and two high molecular weight forms (21, 23 kD), representing alternative translation products from a single mRNA. The 18 kD isoform shows mainly cytoplasmatic localization, whereas the 21/23 kD FGF-2 are localized in the nucleus. In addition, the FGF-2 isoforms are differentially regulated in the sensory ganglia and peripheral nerve following nerve injury and in the adrenal medulla during post-natal development and after hormonal stimuli. The distinct intracellular distribution and differential regulation of the different FGF-2 isoforms indicate that they have unique biological roles, however, little is known about the biological effects of the high molecular weight FGF-2 isoforms. Immortalized Schwann cells and PC12 cells, which stably overexpress the different FGF-2 isoforms, showed that the different endogenous-overexpressed FGF-2 isoforms lead to dramatic modifications in cell proliferation and survival, when tested in serum-free and serum-containing medium. In contrast, application of recombinant FGF-2 isoforms on normal PC12 and immortalized Schwann cells results in similar biological effects on the proliferation and survival of the cells. Furthermore, we investigated the potential regulatory effects of endogenous-overexpressed and exogenous-applied FGF-2 isoforms on the mRNA level of the FGF-2 receptors and, additionally, on the tyrosin hydroxylase mRNA expression in PC12 cells.

  9. Combination of acellular nerve graft and schwann cells-like cells for rat sciatic nerve regeneration.

    Science.gov (United States)

    Gao, Songtao; Zheng, Yan; Cai, Qiqing; Deng, Zhansheng; Yao, Weitao; Wang, Jiaqiang; Wang, Xin; Zhang, Peng

    2014-01-01

    To investigate the effect of tissue engineering nerve on repair of rat sciatic nerve defect. Forty-five rats with defective sciatic nerve were randomly divided into three groups. Rats in group A were repaired by acellular nerve grafts only. Rats in group B were repaired by tissue engineering nerve. In group C, rats were repaired by autogenous nerve grafts. After six and twelve weeks, sciatic nerve functional index (SFI), neural electrophysiology (NEP), histological and transmission electron microscope observation, recovery ratio of wet weight of gastrocnemius muscle, regenerated myelinated nerve fibers number, nerve fiber diameter, and thickness of the myelin sheath were measured to assess the effect. After six and twelve weeks, the recovery ratio of SFI and wet weight of gastrocnemius muscle, NEP, and the result of regenerated myelinated nerve fibers in groups B and C were superior to that of group A (P 0.05). The tissue engineering nerve composed of acellular allogenic nerve scaffold and Schwann cells-like cells can effectively repair the nerve defect in rats and its effect was similar to that of the autogenous nerve grafts.

  10. 施万细胞发育研究进展%New Insights on Schwann Cell Development

    Institute of Scientific and Technical Information of China (English)

    Kelly R Monk; M Laura Feltri; Carla Taveggia

    2015-01-01

    在周围神经系统中,施万细胞属于胶质细胞,在整个神经发育过程中与轴索有密切的关系。施万细胞形成绝缘鞘,并给其包裹的神经元提供必不可少的营养支持。施万细胞前体细胞来源于神经嵴干细胞,一套高度有序的发育程序控制其发育为成熟的髓鞘形成施万细胞或非髓鞘形成施万细胞。本文将结合最新研究发现及近期研究进展,从细胞-细胞及细胞-基质信号通路角度探讨驱动施万细胞发育和髓鞘形成的分子机制。%In the peripheral nervous system, Schwann cells are glial cells that are in intimate contact with axons throughout development. Schwann cells generate the insulating myelin sheath and provide vital trophic support to the neurons that they ensheathe. Schwann cell precursors arise from neural crest progenitor cells, and a highly or-dered developmental sequence controls the progression of these cells to become mature myelinating or nonmyeli-nating Schwann cells. Here, we discuss both seminal discoveries and recent advances in our understanding of the molecular mechanisms that drive Schwann cell development and myelination with a focus on cell–cell and cell–matrix signaling events.

  11. Dorsal root ganglion-derived Schwann cells combined with poly(lactic-co-glycolic acid)/chitosan conduits for the repair of sciatic nerve defects in rats.

    Science.gov (United States)

    Zhao, Li; Qu, Wei; Wu, Yuxuan; Ma, Hao; Jiang, Huajun

    2014-11-15

    Schwann cells, nerve regeneration promoters in peripheral nerve tissue engineering, can be used to repair both the peripheral and central nervous systems. However, isolation and purification of Schwann cells are complicated by contamination with fibroblasts. Current reported measures are mainly limited by either high cost or complicated procedures with low cell yields or purity. In this study, we collected dorsal root ganglia from neonatal rats from which we obtained highly purified Schwann cells using serum-free melanocyte culture medium. The purity of Schwann cells (> 95%) using our method was higher than that using standard medium containing fetal bovine serum. The obtained Schwann cells were implanted into poly(lactic-co-glycolic acid)/chitosan conduits to repair 10-mm sciatic nerve defects in rats. Results showed that axonal diameter and area were significantly increased and motor functions were obviously improved in the rat sciatic nerve tissue. Experimental findings suggest that serum-free melanocyte culture medium is conducive to purify Schwann cells and poly(lactic-co-glycolic acid)/chitosan nerve conduits combined with Schwann cells contribute to restore sciatic nerve defects.

  12. Dorsal root ganglion-derived Schwann cells combined with poly(lactic-co-glycolic acid)/chitosan conduits for the repair of sciatic nerve defects in rats

    Institute of Scientific and Technical Information of China (English)

    Li Zhao; Wei Qu; Yuxuan Wu; Hao Ma; Huajun Jiang

    2014-01-01

    Schwann cells, nerve regeneration promoters in peripheral nerve tissue engineering, can be used to repair both the peripheral and central nervous systems. However, isolation and puriifcation of Schwann cells are complicated by contamination with ifbroblasts. Current reported measures are mainly limited by either high cost or complicated procedures with low cell yields or purity. In this study, we collected dorsal root ganglia from neonatal rats from which we obtained highly puriifed Schwann cells using serum-free melanocyte culture medium. The purity of Schwann cells (> 95%) using our method was higher than that using standard medium containing fetal bovine serum. The obtained Schwann cells were implanted into poly(lactic-co-glycolic acid)/chi-tosan conduits to repair 10-mm sciatic nerve defects in rats. Results showed that axonal diameter and area were signiifcantly increased and motor functions were obviously improved in the rat sciatic nerve tissue. Experimental ifndings suggest that serum-free melanocyte culture medium is conducive to purify Schwann cells and poly(lactic-co-glycolic acid)/chitosan nerve conduits combined with Schwann cells contribute to restore sciatic nerve defects.

  13. Survival and migration of Schwann cells after the vascularized peripheral nerve grafted into spinal cord in rats

    Institute of Scientific and Technical Information of China (English)

    GUO Qing-shan; WANG Ai-min; WANG Xiao-jun; SUN Hong-zhen; DU Quan-yin

    2005-01-01

    Objective:To study the survival and ability of inducing axonal regeneration of the Schwann cells after the peripheral nerve being grafted into spinal cord. Methods:A total of 30 adult female Wistar rats were randomly divided into the VN (vascularized peripheral nerve) and PN (peripheral nerve) groups. A 5-mm spinal cord defect of the left posterior column was made at the T1-3 vertebral level. The defect was grafted with the vascularized or isolated peripheral nerve respectively. The survival and proliferation of the Schwann cells were assessed by histological and morphometric analysis 8 weeks after the operation. Results:In the VN group, the peripheral nerve grew into the cord with lots of Schwann cells survived and proliferated, and had more NF and S-100 positive fibers than in the PN group. Conclusion:The vascularized peripheral nerve enhances the survival and proliferation of the Schwann cells and prompts the regeneration of injured axon of the central nerve system to certain degree.

  14. 17β-Estradiol Promotes Schwann Cell Proliferation and Differentiation, Accelerating Early Remyelination in a Mouse Peripheral Nerve Injury Model

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    Yan Chen

    2016-01-01

    Full Text Available Estrogen induces oligodendrocyte remyelination in response to demyelination in the central nervous system. Our objective was to determine the effects of 17β-estradiol (E2 on Schwann cell function and peripheral nerve remyelination after injury. Adult male C57BL/6J mice were used to prepare the sciatic nerve transection injury model and were randomly categorized into control and E2 groups. To study myelination in vitro, dorsal root ganglion (DRG explant culture was prepared using 13.5-day-old mouse embryos. Primary Schwann cells were isolated from the sciatic nerves of 1- to 3-day-old Sprague–Dawley rats. Immunostaining for myelin basic protein (MBP expression and toluidine blue staining for myelin sheaths demonstrated that E2 treatment accelerates early remyelination in the “nerve bridge” region between the proximal and distal stumps of the transection injury site in the mouse sciatic nerve. The 5-bromo-2′-deoxyuridine incorporation assay revealed that E2 promotes Schwann cell proliferation in the bridge region and in the primary culture, which is blocked using AKT inhibitor MK2206. The in vitro myelination in the DRG explant culture determined showed that the MBP expression in the E2-treated group is higher than that in the control group. These results show that E2 promotes Schwann cell proliferation and myelination depending on AKT activation.

  15. IN VIVO BIOLUMINESCENT IMAGING OF SCHWANN CELLS IN A POLY(DL-LACTIDE-epsilon-CAPROLACTONE) NERVE GUIDE

    NARCIS (Netherlands)

    Ma, Ming-San; Van Dam, Gooitzen; Meek, Marcel; Boddeke, Erik; Copray, Sjef

    2009-01-01

    Nerve guides seeded with Schwann cells (SCs) promote axonal regeneration in peripheral nerve lesions. We examined the applicability of bioluminescent imaging (BLI) for monitoring the fate of SCs in nerve guides after implantation. Rat SCs were transfected with the firefly luciferase (Fluc) gene and

  16. The key components of Schwann cell-like differentiation medium and their effects on gene expression pattern of adipose-derived stem cells.

    Science.gov (United States)

    Orbay, Hakan; Little, Christopher J; Lankford, Lee; Olson, Christine A; Sahar, David E

    2015-05-01

    Schwann cell-like cells differentiated from adipose-derived stem cells may have an important role in peripheral nerve regeneration. Herein, we document the individual effects of growth factors in Schwann cell-like differentiation medium. There were 6 groups in the study. In the control group, we supplemented the rat adipose-derived stem cells with normal cell culture medium. In group 1, we fed the cells with Schwann cell-like differentiation medium (normal cell culture medium supplemented with platelet-derived growth factor, basic fibroblast growth factor, forskolin, and glial growth factor). In the other groups, we removed the components of the medium one at a time from the differentiation medium so that group 2 lacked glial growth factor, group 3 lacked forskolin, group 4 lacked basic fibroblast growth factor, and group 5 lacked platelet-derived growth factor. We examined the expression of the Schwann cell-specific genes with quantitative reverse transcription polymerase chain reaction and immunofluorescence staining in each group. Groups 3 and 4, lacking forskolin and basic fibroblast growth factor, respectively, had the highest expression levels of integrin-β4, and p75. Group 1 showed a 3.2-fold increase in the expression of S100, but the expressions of integrin-β4 and p75 were significantly lower compared to groups 3 and 4. Group 2 [glial growth factor (-)] did not express significant levels of Schwann cell-specific genes. The gene expression profile in group 4 most closely resembled Schwann cells. Immunofluorescence staining results were parallel with the quantitative real-time polymerase chain reaction results. Glial growth factor is a key component of Schwann cell-like differentiation medium.

  17. Neoplasms with schwannian differentiation express transcription factors known to regulate normal schwann cell development.

    Science.gov (United States)

    Pytel, Peter; Karrison, Theodore; Can Gong; Tonsgard, James H; Krausz, Thomas; Montag, Anthony G

    2010-12-01

    A number of transcription factors have been identified as important in guiding normal Schwann cell development. This study used immunohistochemistry on tissue arrays to assess the expression of some of these transcription factors (Sox5, Sox9, Sox10, AP-2α, Pax7, and FoxD3) on 76 schwannomas, 105 neurofibromas, and 34 malignant peripheral nerve sheath tumors (MPNSTs). Sox9 and Sox10 were found to be widely expressed in all tumor types. FoxD3 reactivity was stronger and more frequently found in schwannomas and MPNSTs than neurofibromas. AP-2α was positive in 31% to 49% of all tumors, but strong reactivity was limited to MPNSTs and schwannomas. Pax7 and Sox5 expression was restricted to subsets of MPNSTs. Statistical analysis showed significant differences between the 3 tumor types in the expression of these markers. No differences were found in the analyzed tumor subgroups, including schwannomas of different sites, schwannomas with or without NF2 association, neurofibromas of different types, or sporadic versus NF1-associated MPNSTs. These results suggest that the transcription factors that guide normal Schwann cell development also play a role in the biology of neoplastic cells with Schwannian differentiation. FoxD3, AP-2α, Pax7, and Sox5 are upregulated in MPNSTs compared with neurofibromas and may be markers of malignant transformation. Screening the expression of FoxD3, Sox9, and Sox10 on 23 cases of other spindle-cell proliferations that may be considered in the differential diagnosis of MPNST, including synovial sarcoma and spindle cell melanoma, suggests that these 3 are helpful markers of Schwannian differentiation in the context of diagnosing MPNSTs.

  18. Neuronal activity in the hub of extrasynaptic Schwann cell-axon interactions

    Directory of Open Access Journals (Sweden)

    Chrysanthi eSamara

    2013-11-01

    Full Text Available The integrity and function of neurons depend on their continuous interactions with glial cells. In the peripheral nervous system glial functions are exerted by Schwann cells (SCs. SCs sense synaptic and extrasynaptic manifestations of action potential propagation and adapt their physiology to support neuronal activity. We review here existing literature data on extrasynaptic bidirectional axon-SC communication, focusing particularly on neuronal activity implications. To shed light on underlying mechanisms, we conduct a thorough analysis of microarray data from SC-rich mouse sciatic nerve at different developmental stages and in neuropathic models. We identify molecules that are potentially involved in SC detection of neuronal activity signals inducing subsequent glial responses. We further suggest that alterations in the activity-dependent axon-SC crosstalk impact on peripheral neuropathies. Together with previously reported data, these observations open new perspectives for deciphering glial mechanisms of neuronal function support.

  19. Schwann cell-derived exosomes enhance axonal regeneration in the peripheral nervous system.

    Science.gov (United States)

    Lopez-Verrilli, María Alejandra; Picou, Frederic; Court, Felipe A

    2013-11-01

    Axonal regeneration in the peripheral nervous system is greatly supported by Schwann cells (SCs). After nerve injury, SCs dedifferentiate to a progenitor-like state and efficiently guide axons to their original target tissues. Contact and soluble factors participate in the crosstalk between SCs and axons during axonal regeneration. Here we show that dedifferentiated SCs secrete nano-vesicles known as exosomes which are specifically internalized by axons. Surprisingly, SC-derived exosomes markedly increase axonal regeneration in vitro and enhance regeneration after sciatic nerve injury in vivo. Exosomes shift the growth cone morphology to a pro-regenerating phenotype and decrease the activity of the GTPase RhoA, involved in growth cone collapse and axon retraction. Altogether, our work identifies a novel mechanism by which SCs communicate with neighboring axons during regenerative processes. We propose that SC exosomes represent an important mechanism by which these cells locally support axonal maintenance and regeneration after nerve damage.

  20. S1P and LPA trigger Schwann cell actin changes and migration.

    Science.gov (United States)

    Barber, Siân C; Mellor, Harry; Gampel, Alex; Scolding, Neil J

    2004-06-01

    The processes by which a Schwann cell (SC) migrates towards, wraps around and, in some cases, myelinates an axon are incompletely understood. The complex morphological rearrangements involved in these events require fundamental changes in the actin cytoskeleton. Sphingosine 1-phosphate (S1P) and lysophosphatidic acid (LPA) are two modulators of the actin cytoskeleton, and receptors for these signalling lipids are expressed on SCs at the time of differentiation. Previous work has revealed a role for LPA in SC survival, morphology and differentiation, but the effects of S1P have received less attention. Here we show that S1P and LPA both cause major rearrangements to the actin cytoskeleton in primary rat SCs and the SCL4.1/F7 rat SC line. S1P and LPA caused formation of lamellipodia and a circular geodesic actin network. We also show that S1P and LPA increased cell migration. The small GTPases RhoA and Rac1 were both activated by S1P/LPA treatment, but the actin rearrangements were dependent on Rac1 and not RhoA. These effects of S1P/LPA could be mimicked by SCL4.1/F7 cell-conditioned medium, which was found to contain S1P. Reduction in cellular synthesis of S1P by adding the sphingosine kinase inhibitor dimethyl sphingosine during medium conditioning reduced the ability of conditioned medium to cause actin rearrangements. These results support a role for S1P as an autocrine signal regulating the actin cytoskeleton during Schwann cell development.

  1. Aberrant Schwann cell lipid metabolism linked to mitochondrial deficits leads to axon degeneration and neuropathy.

    Science.gov (United States)

    Viader, Andreu; Sasaki, Yo; Kim, Sungsu; Strickland, Amy; Workman, Cayce S; Yang, Kui; Gross, Richard W; Milbrandt, Jeffrey

    2013-03-06

    Mitochondrial dysfunction is a common cause of peripheral neuropathy. Much effort has been devoted to examining the role played by neuronal/axonal mitochondria, but how mitochondrial deficits in peripheral nerve glia (Schwann cells [SCs]) contribute to peripheral nerve diseases remains unclear. Here, we investigate a mouse model of peripheral neuropathy secondary to SC mitochondrial dysfunction (Tfam-SCKOs). We show that disruption of SC mitochondria activates a maladaptive integrated stress response (ISR) through the actions of heme-regulated inhibitor (HRI) kinase, and causes a shift in lipid metabolism away from fatty acid synthesis toward oxidation. These alterations in SC lipid metabolism result in depletion of important myelin lipid components as well as in accumulation of acylcarnitines (ACs), an intermediate of fatty acid β-oxidation. Importantly, we show that ACs are released from SCs and induce axonal degeneration. A maladaptive ISR as well as altered SC lipid metabolism are thus underlying pathological mechanisms in mitochondria-related peripheral neuropathies.

  2. Coculture of Primary Motor Neurons and Schwann Cells as a Model for In Vitro Myelination.

    Science.gov (United States)

    Hyung, Sujin; Yoon Lee, Bo; Park, Jong-Chul; Kim, Jinseok; Hur, Eun-Mi; Francis Suh, Jun-Kyo

    2015-10-12

    A culture system that can recapitulate myelination in vitro will not only help us better understand the mechanism of myelination and demyelination, but also find out possible therapeutic interventions for treating demyelinating diseases. Here, we introduce a simple and reproducible myelination culture system using mouse motor neurons (MNs) and Schwann cells (SCs). Dissociated motor neurons are plated on a feeder layer of SCs, which interact with and wrap around the axons of MNs as they differentiate in culture. In our MN-SC coculture system, MNs survived over 3 weeks and extended long axons. Both viability and axon growth of MNs in the coculture were markedly enhanced as compared to those of MN monoculture. Co-labeling of myelin basic proteins (MBPs) and neuronal microtubules revealed that SC formed myelin sheaths by wrapping around the axons of MNs. Furthermore, using the coculture system we found that treatment of an antioxidant substance coenzyme Q10 (Co-Q10) markedly facilitated myelination.

  3. Influence of mechanical properties of alginate-based substrates on the performance of Schwann cells in culture.

    Science.gov (United States)

    Ning, Liqun; Xu, Yitong; Chen, Xiongbiao; Schreyer, David J

    2016-06-01

    In tissue engineering, artificial tissue scaffolds containing living cells have been studied for tissue repair and regeneration. Notably, the performance of these encapsulated-in-scaffolds cells in terms of cell viability, proliferation, and expression of function during and after the scaffold fabrication process, has not been well documented because of the influence of mechanical, chemical, and physical properties of the scaffold substrate materials. This paper presents our study on the influence of mechanical properties of alginate-based substrates on the performance of Schwann cells, which are the major glial cells of peripheral nervous system. Given the fact that alginate polysaccharide hydrogel has poor cell adhesion properties, in this study, we examined several types of cell-adhesion supplements and found that alginate covalently modified with RGD peptide provided improved cell proliferation and adhesion. We prepared alginate-based substrates for cell culture using varying alginate concentrations for altering their mechanical properties, which were confirmed by compression testing. Then, we examined the viability, proliferation, morphology, and expression of the extracellular matrix protein laminin of Schwann cells that were seeded on the surface of alginate-based substrates (or 2D culture) or encapsulated within alginate-based substrates (3D cultures), and correlated the examined cell performance to the alginate concentration (or mechanical properties) of hydrogel substrates. Our findings suggest that covalent attachment of RGD peptide can improve the success of Schwann cell encapsulation within alginate-based scaffolds, and provide guidance for regulating the mechanical properties of alginate-based scaffolds containing Schwann cells for applications in peripheral nervous system regeneration and repair.

  4. Impact of scaffold micro and macro architecture on Schwann cell proliferation under dynamic conditions in a rotating wall vessel bioreactor

    Energy Technology Data Exchange (ETDEWEB)

    Valmikinathan, Chandra M.; Hoffman, John [Department of Chemistry, Chemical Biology and Biomedical Engineering, Stevens Institute of Technology, Hoboken, NJ, 07030 (United States); Yu, Xiaojun, E-mail: xyu@stevens.edu [Department of Chemistry, Chemical Biology and Biomedical Engineering, Stevens Institute of Technology, Hoboken, NJ, 07030 (United States)

    2011-01-01

    Over the last decade tissue engineering has emerged as a powerful alternative to regenerate lost tissues owing to trauma or tumor. Evidence shows that Schwann cell containing scaffolds have improved performance in vivo as compared to scaffolds that depend on cellularization post implantation. However, owing to limited supply of cells from the patients themselves, several approaches have been taken to enhance cell proliferation rates to produce complete and uniform cellularization of scaffolds. The most common approach is the application of a bioreactor to enhance cell proliferation rate and therefore reduce the time needed to obtain sufficiently significant number of glial cells, prior to implantation. In this study, we show the application of a rotating wall bioreactor system for studying Schwann cell proliferation on nanofibrous spiral shaped scaffolds, prepared by solvent casting and salt leaching techniques. The scaffolds were fabricated from polycaprolactone (PCL), which has ideal mechanical properties and upon degradation does not produce acidic byproducts. The spiral scaffolds were coated with aligned or random nanofibers, produced by electrospinning, to provide a substrate that mimics the native extracellular matrix and the essential contact guidance cues. At the 4 day time point, an enhanced rate of cell proliferation was observed on the open structured nanofibrous spiral scaffolds in a rotating wall bioreactor, as compared to static culture conditions. However, the cell proliferation rate on the other contemporary scaffolds architectures such as the tubular and cylindrical scaffolds show reduced cell proliferation in the bioreactor as compared to static conditions, at the same time point. Moreover, the rotating wall bioreactor does not alter the orientation or the phenotype of the Schwann cells on the aligned nanofiber containing scaffolds, wherein, the cells remain aligned along the length of the scaffolds. Therefore, these open structured spiral

  5. The role of biodegradable engineered scaffolds seeded with Schwann cells for spinal cord regeneration.

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    Tabesh, H; Amoabediny, Gh; Nik, N Salehi; Heydari, M; Yosefifard, M; Siadat, S O Ranaei; Mottaghy, K

    2009-02-01

    Spinal cord injury is very complicated, as there are factors in the body that inhibit its repair. Although regeneration of the mammalian central nervous system (CNS) was once thought to be impossible, studies over the past two decades have shown that axonal growth after spinal cord injury can occur when provided with the correct substratum. Traditionally, tissue transplantation or peripheral nerve grafting are used to repair damaged or diseased regions of the CNS, but donor shortage and immunological problems associated with infectious disease are often encountered. Fortunately, recent advances in neuroscience, cell culture, and biomaterials provide optimistic future using new treatments for nerve injuries. Biomaterial scaffold creates substrate within which cells are instructed to form a tissue or an organ in a highly controlled way. The principal function of a scaffold is to direct cell behavior such as migration, proliferation, differentiation, maintenance of phenotype, and apoptosis by facilitating sensing and responding to the environment via cell-matrix and cell-cell communications. Therefore, having such abilities provides scaffolds seeded with a special type of cell as an important part of tissue engineering and regenerative medicine which spinal cord regeneration is an example of. Nevertheless, the vast number of biodegradable synthetic and natural biopolymers makes choosing the right one very difficult. In this review article, it was tried to provide an inclusive survey of biopolymers seeded with Schwann cells (SCs) to be used for axonal regeneration in the nervous system.

  6. Distribution and role in regeneration of N-CAM in the basal laminae of muscle and Schwann cells.

    Science.gov (United States)

    Rieger, F; Nicolet, M; Pinçon-Raymond, M; Murawsky, M; Levi, G; Edelman, G M

    1988-08-01

    The neural cell adhesion molecule (N-CAM) is a membrane glycoprotein involved in neuron-neuron and neuron-muscle adhesion. It can be synthesized in various forms by both nerve and muscle and it becomes concentrated at the motor endplate. Biochemical analysis of a frog muscle extract enriched in basal lamina revealed the presence of a polydisperse, polysialylated form of N-CAM with an average Mr of approximately 160,000 as determined by SDS-PAGE, which was converted to a form of 125,000 Mr by treatment with neuraminidase. To define further the role of N-CAM in neuromuscular junction organization, we studied the distribution of N-CAM in an in vivo preparation of frog basal lamina sheaths obtained by inducing the degeneration of both nerve and muscle fibers. Immunoreactive material could be readily detected by anti-N-CAM antibodies in such basal lamina sheaths. Ultrastructural analysis using immunogold techniques revealed N-CAM in close association with the basal lamina sheaths, present in dense accumulation at places that presumably correspond to synaptic regions. N-CAM epitopes were also associated with collagen fibrils in the extracellular matrix. The ability of anti-N-CAM antibodies to perturb nerve regeneration and reinnervation of the remaining basal lamina sheaths was then examined. In control animals, myelinating Schwann cells wrapped around the regenerated axon and reinnervation occurred only at the old synaptic areas; new contacts between nerve and basal lamina had a terminal Schwann cell capping the nerve terminal. In the presence of anti-N-CAM antibodies, three major abnormalities were observed in the regeneration and reinnervation processes: (a) regenerated axons in nerve trunks that had grown back into the old Schwann cell basal lamina were rarely associated with myelinating Schwann cell processes, (b) ectopic synapses were often present, and (c) many of the axon terminals lacked a terminal Schwann cell capping the nerve-basal lamina contact area. These

  7. Hyperglycemia Promotes Schwann Cell De-differentiation and De-myelination via Sorbitol Accumulation and Igf1 Protein Down-regulation.

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    Hao, Wu; Tashiro, Syoichi; Hasegawa, Tomoka; Sato, Yuiko; Kobayashi, Tami; Tando, Toshimi; Katsuyama, Eri; Fujie, Atsuhiro; Watanabe, Ryuichi; Morita, Mayu; Miyamoto, Kana; Morioka, Hideo; Nakamura, Masaya; Matsumoto, Morio; Amizuka, Norio; Toyama, Yoshiaki; Miyamoto, Takeshi

    2015-07-10

    Diabetes mellitus (DM) is frequently accompanied by complications, such as peripheral nerve neuropathy. Schwann cells play a pivotal role in regulating peripheral nerve function and conduction velocity; however, changes in Schwann cell differentiation status in DM are not fully understood. Here, we report that Schwann cells de-differentiate into immature cells under hyperglycemic conditions as a result of sorbitol accumulation and decreased Igf1 expression in those cells. We found that de-differentiated Schwann cells could be re-differentiated in vitro into mature cells by treatment with an aldose reductase inhibitor, to reduce sorbitol levels, or with vitamin D3, to elevate Igf1 expression. In vivo DM models exhibited significantly reduced nerve function and conduction, Schwann cell de-differentiation, peripheral nerve de-myelination, and all conditions were significantly rescued by aldose reductase inhibitor or vitamin D3 administration. These findings reveal mechanisms underlying pathological changes in Schwann cells seen in DM and suggest ways to treat neurological conditions associated with this condition.

  8. Predegenerated Schwann cells–a novel prospect for cell therapy for glaucoma: neuroprotection, neuroregeneration and neuroplasticity

    Science.gov (United States)

    Smedowski, Adrian; Liu, Xiaonan; Pietrucha-Dutczak, Marita; Matuszek, Iwona; Varjosalo, Markku; Lewin-Kowalik, Joanna

    2016-01-01

    Glaucoma is an optic neuropathy that leads to irreversible blindness. Because the current therapies are not sufficient to protect against glaucoma-induced visual impairment, new treatment approaches are necessary to prevent disease progression. Cell transplantation techniques are currently considered to be among the most promising opportunities for nervous system damage treatment. The beneficial effects of undifferentiated cells have been investigated in experimental models of glaucoma, however experiments were accompanied by various barriers, which would make putative treatment difficult or even impossible to apply in a clinical setting. The novel therapy proposed in our study creates conditions to eliminate some of the identified barriers described for precursor cells transplantation and allows us to observe direct neuroprotective and pro-regenerative effects in ongoing optic neuropathy without additional modifications to the transplanted cells. We demonstrated that the proposed novel Schwann cell therapy might be promising, effective and easy to apply, and is safer than the alternative cell therapies for the treatment of glaucoma. PMID:27034151

  9. Neurospheres from rat adipose-derived stem cells could be induced into functional Schwann cell-like cells in vitro

    Directory of Open Access Journals (Sweden)

    Shan Yanchang

    2008-02-01

    Full Text Available Abstract Background Schwann cells (SC which are myelin-forming cells in peripheral nervous system are very useful for the treatment of diseases of peripheral nervous system and central nervous system. However, it is difficult to obtain sufficient large number of SC for clinical use, so alternative cell systems are desired. Results Using a procedure similar to the one used for propagation of neural stem cells, we could induce rat adipose-derived stem cells (ADSC into floating neurospheres. In addition to being able to differentiate into neuronal- and glial-like cells, neurospheres could be induced to differentiate into SC-like cells. SC-like cells were bi- or tri-polar in shape and immunopositive for nestin and SC markers p75, GFAP and S-100, identical to genuine SC. We also found that SC-like cells could induce the differentiation of SH-SY5Y neuroblastoma cells efficiently, perhaps through secretion of soluble substances. We showed further that SC-like cells could form myelin structures with PC12 cell neurites in vitro. Conclusion These findings indicated that ADSC could differentiate into SC-like cells in terms of morphology, phenotype and functional capacities. SC-like cells induced from ADSC may be useful for the treatment of neurological diseases.

  10. Schwann Cell-Mediated Preservation of Vision in Retinal Degenerative Diseases via the Reduction of Oxidative Stress: A Possible Mechanism

    Science.gov (United States)

    MAHMOUDZADEH, Raziyeh; HEIDARI-KESHEL, Saeed; LASHAY, Alireza

    2016-01-01

    After injury to the central nervous system (CNS), regeneration is often inadequate, except in the case of remyelination. This remyelination capacity of the CNS is a good example of a stem/precursor cell-mediated renewal process. Schwann cells have been found to act as remyelinating agents in the peripheral nervous system (PNS), but several studies have highlighted their potential role in remyelination in the CNS too. Schwann cells are able to protect and support retinal cells by secreting growth factors such as brain-derived neurotrophic factor, glial cell line-derived neurotrophic factor, and basic fibroblast growth factor. Retinal degenerative diseases can be highly debilitating, and they are a major concern in countries with an ageing populations. One of the leading causes of permanent loss of vision in the West is a retinal degenerative disease known as age-related macular degeneration (AMD). In the United States, nearly 1.75 million people over the age of 40 have advanced AMD, and it is estimated that this number will increase to approximately 3 million people by 2020. One of the most common pathways involved in the initiation and development of retinal diseases is the oxidative stress pathway. In patients with diabetes, Schwann cells have been shown to be able to secrete large amounts of antioxidant enzymes that protect the PNS from the oxidative stress that results from fluctuations in blood glucose levels. This antioxidant ability may be involved in the mechanism by which Schwann cells are able to promote reconstruction in the CNS, especially in individuals with retinal injuries and degenerative diseases. PMID:28293647

  11. Activation of Schwann cells in vitro by magnetic nanocomposites via applied magnetic field

    Directory of Open Access Journals (Sweden)

    Liu Z

    2014-12-01

    Full Text Available Zhongyang Liu,1,* Liangliang Huang,1,* Liang Liu,1,* Beier Luo,2,* Miaomiao Liang,3 Zhen Sun,1 Shu Zhu,1 Xin Quan,1 Yafeng Yang,1 Teng Ma,1 Jinghui Huang,1 Zhuojing Luo1 1Department of Orthopaedics, Xijing Hospital, Fourth Military Medical University, Xi’an, 2Department of Orthopaedics, Changhai Hospital, Second Military Medical University, Shanghai, 3Department of Neurosurgery, Xijing Hospital, Fourth Military Medical University, Xi’an, People’s Republic of China *These authors contributed equally to this work Abstract: Schwann cells (SCs are attractive seed cells in neural tissue engineering, but their application is limited by attenuated biological activities and impaired functions with aging. Therefore, it is important to explore an approach to enhance the viability and biological properties of SCs. In the present study, a magnetic composite made of magnetically responsive magnetic nanoparticles (MNPs and a biodegradable chitosan–glycerophosphate polymer were prepared and characterized. It was further explored whether such magnetic nanocomposites via applied magnetic fields would regulate SC biological activities. The magnetization of the magnetic nanocomposite was measured by a vibrating sample magnetometer. The compositional characterization of the magnetic nanocomposite was examined by Fourier-transform infrared and X-ray diffraction. The tolerance of SCs to the magnetic fields was tested by flow-cytometry assay. The proliferation of cells was examined by a 5-ethynyl-2-deoxyuridine-labeling assay, a PrestoBlue assay, and a Live/Dead assay. Messenger ribonucleic acid of BDNF, GDNF, NT-3, and VEGF in SCs was assayed by quantitative real-time polymerase chain reaction. The amount of BDNF, GDNF, NT-3, and VEGF secreted from SCs was determined by enzyme-linked immunosorbent assay. It was found that magnetic nanocomposites containing 10% MNPs showed a cross-section diameter of 32.33±1.81 µm, porosity of 80.41%±0.72%, and

  12. A novel function of RING finger protein 10 in transcriptional regulation of the myelin-associated glycoprotein gene and myelin formation in Schwann cells.

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    Shinya Hoshikawa

    Full Text Available Myelin-associated glycoprotein (MAG has been detected in Schwann cells prior to the onset of myelination, suggesting its functions in the initiation of myelination. However, transcriptional regulatory mechanisms of MAG remain to be elucidated. Here, we analyzed the promoter of the MAG gene by using luciferase reporter systems in the primary rat Schwann cells. We identified a novel cis-acting element located 160 bp upstream from the MAG transcription initiation site. Using the identified cis-element as a bait, we performed yeast one-hybrid screening and isolated a cDNA encoding a RNF10 as a putative trans-acting protein. When overexpressed in Schwann cells, RNF10 enhanced the activity of the MAG promoter. When RNF10 expression in Schwann cells was knocked down by siRNA, endogenous MAG mRNA and protein expression decreased. Furthermore, we evaluated myelin synthesis using Schwann cell-DRG neuron cocultures. When Schwann cells were infected with retrovirus expressing RNF10 siRNA, myelin formation was inhibited. These data suggest that RNF10 regulates MAG expression and is required for myelin formation.

  13. Human autologous serum as a substitute for fetal bovine serum in human Schwann cell culture.

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    Parisa Goodarzi

    2014-04-01

    Full Text Available Nowadays, cell -based and tissue engineered products have opened new horizons in treatment of incurable nervous system disorders. The number of studies on the role of Schwann cells (SC in treating nervous disorders is higher than other cell types. Different protocols have been suggested for isolation and expansion of SC which most of them have used multiple growth factors, mitogens and fetal bovine sera (FBS in culture medium. Because of potential hazards of animal-derived reagents, this study was designed to evaluate the effect of replacing FBS with human autologous serum (HAS on SC's yield and culture parameters. Samples from 10 peripheral nerve biopsies were retrieved and processed under aseptic condition. The isolated cells cultured in FBS (1st group or autologous serum (2nd group. After primary culture the cells were seeded at 10000 cell/cm2 in a 12 wells cell culture plate for each group. At 100% confluency, the cell culture parameters (count, viability, purity and culture duration of 2 groups were compared using paired t-test. The average donors' age was 35.80 (SD=13.35 and except for 1 sample the others cultured successfully. In first group, the averages of cell purity, viability and culture duration were 97% (SD=1.32, 97/33% (SD=1.22 and 11.77 (SD=2.58 days respectively. This parameters were 97.33% (SD=1.00, 97.55% (SD=1.33 and 10.33 days (SD=1.65 in second group. The difference of cell count, purity and viability were not significant between 2 groups (P>0.05. The cells of second group reached to 100% confluency in shorter period of time (P=0.03. The results of this study showed that autologous serum can be a good substitute for FBS in human SC culture. This can reduce the costs and improve the safety of cell product for clinical application.

  14. Mycobacterium leprae downregulates the expression of PHEX in Schwann cells and osteoblasts

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    Sandra R Boiça Silva

    2010-08-01

    Full Text Available Neuropathy and bone deformities, lifelong sequelae of leprosy that persist after treatment, result in significant impairment to patients and compromise their social rehabilitation. Phosphate-regulating gene with homologies to endopeptidase on the X chromosome (PHEX is a Zn-metalloendopeptidase, which is abundantly expressed in osteoblasts and many other cell types, such as Schwann cells, and has been implicated in phosphate metabolism and X-linked rickets. Here, we demonstrate that Mycobacterium leprae stimulation downregulates PHEX transcription and protein expression in a human schwannoma cell line (ST88-14 and human osteoblast lineage. Modulation of PHEX expression was observed to a lesser extent in cells stimulated with other species of mycobacteria, but was not observed in cultures treated with latex beads or with the facultative intracellular bacterium Salmonella typhimurium. Direct downregulation of PHEX by M. leprae could be involved in the bone resorption observed in leprosy patients. This is the first report to describe PHEX modulation by an infectious agent.

  15. Schwann cells are activated by ATP released from neurons in an in vitro cellular model of Miller Fisher syndrome

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    Umberto Rodella

    2017-05-01

    Full Text Available The neuromuscular junction is exposed to different types of insult, including mechanical trauma, toxins and autoimmune antibodies and, accordingly, has retained through evolution a remarkable ability to regenerate. Regeneration is driven by multiple signals that are exchanged among the cellular components of the junction. These signals are largely unknown. Miller Fisher syndrome is a variant of Guillain–Barré syndrome caused by autoimmune antibodies specific for epitopes of peripheral axon terminals. Using an animal model of Miller Fisher syndrome, we recently reported that a monoclonal anti-polysialoganglioside GQ1b antibody plus complement damages nerve terminals with production of mitochondrial hydrogen peroxide, which activates Schwann cells. Several additional signaling molecules are likely to be involved in the activation of the regeneration program in these cells. Using an in vitro cellular model consisting of co-cultured primary neurons and Schwann cells, we found that ATP is released by neurons injured by the anti-GQ1b antibody plus complement. Neuron-derived ATP acts as an alarm messenger for Schwann cells, where it induces the activation of intracellular pathways, including calcium signaling, cAMP and CREB, which, in turn, produce signals that promote nerve regeneration. These results contribute to defining the cross-talk taking place at the neuromuscular junction when it is attacked by anti-gangliosides autoantibodies plus complement, which is crucial for nerve regeneration and is also likely to be important in other peripheral neuropathies.

  16. Schwann Cell Expressed Nogo-B Modulates Axonal Branching of Adult Sensory Neurons Through the Nogo-B Receptor NgBR.

    Science.gov (United States)

    Eckharter, Christoph; Junker, Nina; Winter, Lilli; Fischer, Irmgard; Fogli, Barbara; Kistner, Steffen; Pfaller, Kristian; Zheng, Binhai; Wiche, Gerhard; Klimaschewski, Lars; Schweigreiter, Rüdiger

    2015-01-01

    In contrast to the central nervous system (CNS) nerve fibers do regenerate in the peripheral nervous system (PNS) although in a clinically unsatisfying manner. A major problem is excessive sprouting of regenerating axons which results in aberrant reinnervation of target tissue and impaired functional recovery. In the CNS, the reticulon protein Nogo-A has been identified as a prominent oligodendrocyte expressed inhibitor of long-distance growth of regenerating axons. We show here that the related isoform Nogo-B is abundantly expressed in Schwann cells in the PNS. Other than Nogo-A in oligodendrocytes, Nogo-B does not localize to the myelin sheath but is detected in the ER and the plasma membrane of Schwann cells. Adult sensory neurons that are cultured on nogo-a/b deficient Schwann cells form significantly fewer axonal branches vs. those on wildtype Schwann cells, while their maximal axonal extension is unaffected. We demonstrate that this effect of Nogo-B on neuronal morphology is restricted to undifferentiated Schwann cells and is mediated by direct physical contact between these two cell types. Moreover, we show that blocking the Nogo-B specific receptor NgBR, which we find expressed on sensory neurons and to interact with Schwann cell expressed Nogo-B, produces the same branching phenotype as observed after deletion of Nogo-B. These data provide evidence for a novel function of the nogo gene that is implemented by the Nogo-B isoform. The remarkably specific effects of Nogo-B/NgBR on axonal branching, while leaving axonal extension unaffected, are of potential clinical relevance in the context of excessive axonal sprouting after peripheral nerve injury. Nogo-B is prominently expressed in Schwann cells and localizes to the ER and plasma membrane. It distributes to the external cytoplasmic compartment of Schwann cells in vivo, but is absent from the myelin sheath.Genetic deletion of Nogo-B in Schwann cells reduces axonal branching, but not long-distance growth, of

  17. Effects of co-engraftment of Schwann cells with neural stem cells into rats with Parkinson disease

    Institute of Scientific and Technical Information of China (English)

    JIANG Cheng-chuan; XIA Ying; DING Zhong-liang; WANG Yang; XU Bin

    2006-01-01

    @@ Neural stem cells (NSCs) are effective in treating Parkinsonian animals.1 Although cell transplantation is considered a promising treatment for Parkinson disease (PD), its clinical use has been limited to only a few patients. The major limiting factors of this therapy are difficulty in obtaining sufficient viable embryonic mesencephalic tissue and the controversial ethical and/or legal issues raised by the use of human fetal allografts.1 Some reports suggest that Schwann cells (SCs) can promote the proliferation of embryonic stem cells and the induction of dopaminergic neurons.2 Our research focused on potential curative effects of co-graft SCs with mesencephalic stem cells into Parkinsonian animals and elucidating the underlying mechanisms.

  18. Exogenous Schwann Cells Migrate, Remyelinate and Promote Clinical Recovery in Experimental Auto-Immune Encephalomyelitis

    Science.gov (United States)

    Zujovic, Violetta; Doucerain, Cédric; Hidalgo, Antoine; Bachelin, Corinne; Lachapelle, François; Weissert, Robert; Stadelmann, Christine; Linington, Chris; Evercooren, Anne Baron-Van

    2012-01-01

    Schwann cell (SC) transplantation is currently being discussed as a strategy that may promote functional recovery in patients with multiple sclerosis (MS) and other inflammatory demyelinating diseases of the central nervous system (CNS). However this assumes they will not only survive but also remyelinate demyelinated axons in the chronically inflamed CNS. To address this question we investigated the fate of transplanted SCs in myelin oligodendrocyte glycoprotein (MOG)-induced experimental autoimmune encephalomyelitis (EAE) in the Dark Agouti rat; an animal model that reproduces the complex inflammatory demyelinating immunopathology of MS. We now report that SCs expressing green fluorescent protein (GFP-SCs) allografted after disease onset not only survive but also migrate to remyelinate lesions in the inflamed CNS. GFP-SCs were detected more frequently in the parenchyma after direct injection into the spinal cord, than via intra-thecal delivery into the cerebrospinal fluid. In both cases the transplanted cells intermingled with astrocytes in demyelinated lesions, aligned with axons and by twenty one days post transplantation had formed Pzero protein immunoreactive internodes. Strikingly, GFP-SCs transplantation was associated with marked decrease in clinical disease severity in terms of mortality; all GFP-SCs transplanted animals survived whilst 80% of controls died within 40 days of disease. PMID:22984406

  19. Exogenous schwann cells migrate, remyelinate and promote clinical recovery in experimental auto-immune encephalomyelitis.

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    Violetta Zujovic

    Full Text Available Schwann cell (SC transplantation is currently being discussed as a strategy that may promote functional recovery in patients with multiple sclerosis (MS and other inflammatory demyelinating diseases of the central nervous system (CNS. However this assumes they will not only survive but also remyelinate demyelinated axons in the chronically inflamed CNS. To address this question we investigated the fate of transplanted SCs in myelin oligodendrocyte glycoprotein (MOG-induced experimental autoimmune encephalomyelitis (EAE in the Dark Agouti rat; an animal model that reproduces the complex inflammatory demyelinating immunopathology of MS. We now report that SCs expressing green fluorescent protein (GFP-SCs allografted after disease onset not only survive but also migrate to remyelinate lesions in the inflamed CNS. GFP-SCs were detected more frequently in the parenchyma after direct injection into the spinal cord, than via intra-thecal delivery into the cerebrospinal fluid. In both cases the transplanted cells intermingled with astrocytes in demyelinated lesions, aligned with axons and by twenty one days post transplantation had formed Pzero protein immunoreactive internodes. Strikingly, GFP-SCs transplantation was associated with marked decrease in clinical disease severity in terms of mortality; all GFP-SCs transplanted animals survived whilst 80% of controls died within 40 days of disease.

  20. Role of Schwann cells in the regeneration of penile and peripheral nerves

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    Lin Wang

    2015-01-01

    Full Text Available Schwann cells (SCs are the principal glia of the peripheral nervous system. The end point of SC development is the formation of myelinating and nonmyelinating cells which ensheath large and small diameter axons, respectively. They play an important role in axon regeneration after injury, including cavernous nerve injury that leads to erectile dysfunction (ED. Despite improvement in radical prostatectomy surgical techniques, many patients still suffer from ED postoperatively as surgical trauma causes traction injuries and local inflammatory changes in the neuronal microenvironment of the autonomic fibers innervating the penis resulting in pathophysiological alterations in the end organ. The aim of this review is to summarize contemporary evidence regarding: (1 the origin and development of SCs in the peripheral and penile nerve system; (2 Wallerian degeneration and SC plastic change following peripheral and penile nerve injury; (3 how SCs promote peripheral and penile nerve regeneration by secreting neurotrophic factors; (4 and strategies targeting SCs to accelerate peripheral nerve regeneration. We searched PubMed for articles related to these topics in both animal models and human research and found numerous studies suggesting that SCs could be a novel target for treatment of nerve injury-induced ED.

  1. RAT GDNF GENE TRANSFECTION AND EXPRESSION OF ITS mRNA AND PROTEIN IN SCHWANN CELLS

    Institute of Scientific and Technical Information of China (English)

    平萍; 范志宏; 李青峰; 张涤生

    2004-01-01

    Objective To investigate the possibility of the transfection of glial-cell line derived neurotrophic factor (GDNF) gene into Schwann cells(SCs). Methods SCs cultures from sciatic nerves of neonatal rats were established. A recombinant retrovirus vector containing GDNF gene was constructed and transferred into SCs.Expression levels of GDNF mRNA and protein were respectively identified with reverse transcriptase-polymerase chain reaction (RT-PCR) and immunocytochemistry. Determination of GDNF synthesis rates from Retro. pLNCX2-GDNF-transduced SCs (GDNF-SCs) in vitro by enzyme-linked immunoassay sensitive assay ( ELISA ). Biololgical activity of conditioned medium from GENF-SCs was analysed by co-culture with rat motoneurons. Results Transfection of GDNF gene into SCs lead to significantly enhanced expression of GDNF mRNA and protein. The rate of GDNF secreted by GDNF-SCs was also enhanced(5. 1-fold), and more motoneurons survived co-cultured with conditioned medium of GNDF-SCs than with that of normal SCs. Conclusion GNDF gene transfection may be a better way to graft SCs promoting regeneration and repairing demyelination in PNS and CNS.

  2. Schwann cell mitochondria as key regulators in the development and maintenance of peripheral nerve axons.

    Science.gov (United States)

    Ino, Daisuke; Iino, Masamitsu

    2017-03-01

    Formation of myelin sheaths by Schwann cells (SCs) enables rapid and efficient transmission of action potentials in peripheral axons, and disruption of myelination results in disorders that involve decreased sensory and motor functions. Given that construction of SC myelin requires high levels of lipid and protein synthesis, mitochondria, which are pivotal in cellular metabolism, may be potential regulators of the formation and maintenance of SC myelin. Supporting this notion, abnormal mitochondria are found in SCs of neuropathic peripheral nerves in both human patients and the relevant animal models. However, evidence for the importance of SC mitochondria in myelination has been limited, until recently. Several studies have recently used genetic approaches that allow SC-specific ablation of mitochondrial metabolic activity in living animals to show the critical roles of SC mitochondria in the development and maintenance of peripheral nerve axons. Here, we review current knowledge about the involvement of SC mitochondria in the formation and dysfunction of myelinated axons in the peripheral nervous system.

  3. A history of plant biotechnology: from the Cell Theory of Schleiden and Schwann to biotech crops.

    Science.gov (United States)

    Vasil, Indra K

    2008-09-01

    Plant biotechnology is founded on the principles of cellular totipotency and genetic transformation, which can be traced back to the Cell Theory of Matthias Jakob Schleiden and Theodor Schwann, and the discovery of genetic transformation in bacteria by Frederick Griffith, respectively. On the 25th anniversary of the genetic transformation of plants, this review provides a historical account of the evolution of the theoretical concepts and experimental strategies that led to the production and commercialization of biotech (transformed or transgenic) plants expressing many useful genes, and emphasizes the beneficial effects of plant biotechnology on food security, human health, the environment, and conservation of biodiversity. In so doing, it celebrates and pays tribute to the contributions of scores of scientists who laid the foundation of modern plant biotechnology by their bold and unconventional thinking and experimentation. It highlights also the many important lessons to be learnt from the fascinating history of plant biotechnology, the significance of history in science teaching and research, and warns against the danger of the growing trends of ignoring history and historical illiteracy.

  4. cAMP and Schwann cells promote axonal growth and functional recovery after spinal cord injury.

    Science.gov (United States)

    Pearse, Damien D; Pereira, Francisco C; Marcillo, Alexander E; Bates, Margaret L; Berrocal, Yerko A; Filbin, Marie T; Bunge, Mary Bartlett

    2004-06-01

    Central neurons regenerate axons if a permissive environment is provided; after spinal cord injury, however, inhibitory molecules are present that make the local environment nonpermissive. A promising new strategy for inducing neurons to overcome inhibitory signals is to activate cAMP signaling. Here we show that cAMP levels fall in the rostral spinal cord, sensorimotor cortex and brainstem after spinal cord contusion. Inhibition of cAMP hydrolysis by the phosphodiesterase IV inhibitor rolipram prevents this decrease and when combined with Schwann cell grafts promotes significant supraspinal and proprioceptive axon sparing and myelination. Furthermore, combining rolipram with an injection of db-cAMP near the graft not only prevents the drop in cAMP levels but increases them above those in uninjured controls. This further enhances axonal sparing and myelination, promotes growth of serotonergic fibers into and beyond grafts, and significantly improves locomotion. These findings show that cAMP levels are key for protection, growth and myelination of injured CNS axons in vivo and recovery of function.

  5. Morphological study of Schwann cells remyelination in contused spinal cord of rats

    Institute of Scientific and Technical Information of China (English)

    LI Yue; ZHANG Lu; ZHANG Jie-yuan; LIU Zheng; DUAN Zhao-xia; LI Bing-cang

    2013-01-01

    Objective:To study the role and effect of Schwann cells (SCs) remyelination in contused spinal cord.Methods:Green fluorescence protein expressing-SCs were transplanted into the epicenter,rostral and caudal tissues of the injury site at 1 week after the spinal cords were contused.At 6 weeks,the spinal cords were removed for cryosections,semithin sections and ultrathin sections,and then immunocytochemical staining of myelin basic protein (MBP),P0 protein (P0) and S 100 protein (S100) was carried out on the cryosections.Qualitative and semiquantitative analyses were performed on the cryosections and semithin sections.Ultrastructure ofmyelinated fibers was observed on the ultrathin sections under electron microscope.Results:Transplanted SCs and myelinated fibers immunocytochemically labeled by MBP,P0 as well as S100 distributed in whole injured area.The quantity of myelinated fibers labeled by the three myelin proteins showed no statistical difference,however,which was significantly larger than that of controls.On the semithin sections,the experimental group demonstrated more myelinated fibers in the injured area than the controls,but the fibers had smaller diameter and thinner myelin sheath under electron microscope.Conclusion:SCs can promote regeneration of injured nerve fibers and enhance remyelination,which may be histological basis of SCs-mediated functional repair of injured spinal cords.

  6. Glutamate signals through mGluR2 to control Schwann cell differentiation and proliferation

    Science.gov (United States)

    Saitoh, Fuminori; Wakatsuki, Shuji; Tokunaga, Shinji; Fujieda, Hiroki; Araki, Toshiyuki

    2016-01-01

    Rapid saltatory nerve conduction is facilitated by myelin structure, which is produced by Schwann cells (SC) in the peripheral nervous system (PNS). Proper development and degeneration/regeneration after injury requires regulated phenotypic changes of SC. We have previously shown that glutamate can induce SC proliferation in culture. Here we show that glutamate signals through metabotropic glutamate receptor 2 (mGluR2) to induce Erk phosphorylation in SC. mGluR2-elicited Erk phosphorylation requires ErbB2/3 receptor tyrosine kinase phosphorylation to limit the signaling cascade that promotes phosphorylation of Erk, but not Akt. We found that Gβγ and Src are involved in subcellular signaling downstream of mGluR2. We also found that glutamate can transform myelinating SC to proliferating SC, while inhibition of mGluR2 signaling can inhibit demyelination of injured nerves in vivo. These data suggest pathophysiological significance of mGluR2 signaling in PNS and its possible therapeutic importance to combat demyelinating disorders including Charcot-Marie-Tooth disease. PMID:27432639

  7. Culturing Schwann Cells from Neonatal Rats by Improved Enzyme Digestion Combined with Explants-culture Method.

    Science.gov (United States)

    Liu, Di; Liang, Xiao-Chun; Zhang, Hong

    2016-08-01

    Objective To develop an improved method for culturing Schwann cells(SCs) by using both enzyme digestion and explants-culture approaches and compared with traditional explants-culture method and general hemi-explants-culture method. Methods Bilaterally sciatic nerves and brachial plexus nerves were dissected from 3 to 5-day-old neonatal SD rats and explants-culture method,general hemi-explants-culture method,and improved enzyme digestion combined with explants-culture method were adopted to culture SCs,respectively. SCs were digested and passaged after 7 days in culture and counted under the microscope. The purity of SCs was identified by S-100 immunofluorescence staining. Results The SCs of improved method group grew fastest and the total number of cells obtained was(1.85±0.13)×10(6);the SCs of the hemi-explants-culture method group grew slower than the improved method group and the total number of cells obtained was (1.10±0.10)×10(6);the SCs of the explants-culture method group grew slowest and the total number of cells obtained was (0.77±0.03)×10(6).The total number of cells obtained showed significant difference among the three groups(Pculture method group,and (74.50±4.23)% in the explants-culture method group(Pculture method can obtain sufficient amount of high-purity SCs in a short time and thus may be applied in further research on peripheral nerve regeneration.

  8. Human Induced Pluripotent Cell-Derived Sensory Neurons for Fate Commitment of Bone Marrow-Derived Schwann Cells: Implications for Remyelination Therapy.

    Science.gov (United States)

    Cai, Sa; Han, Lei; Ao, Qiang; Chan, Ying-Shing; Shum, Daisy Kwok-Yan

    2016-09-14

    : Strategies that exploit induced pluripotent stem cells (iPSCs) to derive neurons have relied on cocktails of cytokines and growth factors to bias cell-signaling events in the course of fate choice. These are often costly and inefficient, involving multiple steps. In this study, we took an alternative approach and selected 5 small-molecule inhibitors of key signaling pathways in an 8-day program to induce differentiation of human iPSCs into sensory neurons, reaching ≥80% yield in terms of marker proteins. Continuing culture in maintenance medium resulted in neuronal networks immunopositive for synaptic vesicle markers and vesicular glutamate transporters suggestive of excitatory neurotransmission. Subpopulations of the derived neurons were electrically excitable, showing tetrodotoxin-sensitive action potentials in patch-clamp experiments. Coculture of the derived neurons with rat Schwann cells under myelinating conditions resulted in upregulated levels of neuronal neuregulin 1 type III in conjunction with the phosphorylated receptors ErbB2 and ErbB3, consistent with amenability of the neuritic network to myelination. As surrogates of embryonic dorsal root ganglia neurons, the derived sensory neurons provided contact-dependent cues to commit bone marrow-derived Schwann cell-like cells to the Schwann cell fate. Our rapid and efficient induction protocol promises not only controlled differentiation of human iPSCs into sensory neurons, but also utility in the translation to a protocol whereby human bone marrow-derived Schwann cells become available for autologous transplantation and remyelination therapy.

  9. Co-transplantation of macaque autologous Schwann cells and human embryonic nerve stem cells in treatment of macaque Parkinson's disease

    Institute of Scientific and Technical Information of China (English)

    Ying Xia; Chengchuan Jiang; Zuowei Cao; Keshan Shi; Yang Wang

    2012-01-01

    Objective:To investigate the therapeutic effects of co-transplantation with Schwann cells (SCs) and human embryonic nerve stem cells (NSCs) on macaque Parkinson's disease (PD). Methods:Macaque autologous SCs and human embryonic NSCs were adopted for the treatment of macaque PD. Results: Six months after transplantation, positron emission computerized tomography showed that 18F-FP-β-CIT was significantly concentrated in the injured striatum in the co-transplanted group. Immunohistochemical staining of transplanted area tissue showed migration of tyroxine hydroxylase positive cells from the transplant area to the surrounding area was significantly increased in the co-transplanted group. Conclusions: Co-transplantation of SCs and NSCs could effectively cure PD in macaques. SCs harvested from the autologous peripheral nerves can avoid rejection and the ethics problems, so it is expected to be applied clinically.

  10. Geometrical versus Random β-TCP Scaffolds: Exploring the Effects on Schwann Cell Growth and Behavior.

    Science.gov (United States)

    Sweet, Lauren; Kang, Yunqing; Czisch, Christopher; Witek, Lukasz; Shi, Yang; Smay, Jim; Plant, Giles W; Yang, Yunzhi

    2015-01-01

    Numerous studies have demonstrated that Schwann cells (SCs) play a role in nerve regeneration; however, their role in innervating a bioceramic scaffold for potential application in bone regeneration is still unknown. Here we report the cell growth and functional behavior of SCs on β-tricalcium phosphate (β-TCP) scaffolds arranged in 3D printed-lattice (P-β-TCP) and randomly-porous, template-casted (N-β-TCP) structures. Our results indicate that SCs proliferated well and expressed the phenotypic markers p75LNGFR and the S100-β subunit of SCs as well as displayed growth morphology on both scaffolds, but SCs showed spindle-shaped morphology with a significant degree of SCs alignment on the P-β-TCP scaffolds, seen to a lesser degree in the N-β-TCP scaffold. The gene expressions of nerve growth factor (β-ngf), neutrophin-3 (nt-3), platelet-derived growth factor (pdgf-bb), and vascular endothelial growth factor (vegf-a) were higher at day 7 than at day 14. While no significant differences in protein secretion were measured between these last two time points, the scaffolds promoted the protein secretion at day 3 compared to that on the cell culture plates. These results together imply that the β-TCP scaffolds can support SC cell growth and that the 3D-printed scaffold appeared to significantly promote the alignment of SCs along the struts. Further studies are needed to investigate the early and late stage relationship between gene expression and protein secretion of SCs on the scaffolds with refined characteristics, thus better exploring the potential of SCs to support vascularization and innervation in synthetic bone grafts.

  11. Geometrical versus Random β-TCP Scaffolds: Exploring the Effects on Schwann Cell Growth and Behavior.

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    Lauren Sweet

    Full Text Available Numerous studies have demonstrated that Schwann cells (SCs play a role in nerve regeneration; however, their role in innervating a bioceramic scaffold for potential application in bone regeneration is still unknown. Here we report the cell growth and functional behavior of SCs on β-tricalcium phosphate (β-TCP scaffolds arranged in 3D printed-lattice (P-β-TCP and randomly-porous, template-casted (N-β-TCP structures. Our results indicate that SCs proliferated well and expressed the phenotypic markers p75LNGFR and the S100-β subunit of SCs as well as displayed growth morphology on both scaffolds, but SCs showed spindle-shaped morphology with a significant degree of SCs alignment on the P-β-TCP scaffolds, seen to a lesser degree in the N-β-TCP scaffold. The gene expressions of nerve growth factor (β-ngf, neutrophin-3 (nt-3, platelet-derived growth factor (pdgf-bb, and vascular endothelial growth factor (vegf-a were higher at day 7 than at day 14. While no significant differences in protein secretion were measured between these last two time points, the scaffolds promoted the protein secretion at day 3 compared to that on the cell culture plates. These results together imply that the β-TCP scaffolds can support SC cell growth and that the 3D-printed scaffold appeared to significantly promote the alignment of SCs along the struts. Further studies are needed to investigate the early and late stage relationship between gene expression and protein secretion of SCs on the scaffolds with refined characteristics, thus better exploring the potential of SCs to support vascularization and innervation in synthetic bone grafts.

  12. Geometrical versus Random β-TCP Scaffolds: Exploring the Effects on Schwann Cell Growth and Behavior

    Science.gov (United States)

    Czisch, Christopher; Witek, Lukasz; Shi, Yang; Smay, Jim; Plant, Giles W.; Yang, Yunzhi

    2015-01-01

    Numerous studies have demonstrated that Schwann cells (SCs) play a role in nerve regeneration; however, their role in innervating a bioceramic scaffold for potential application in bone regeneration is still unknown. Here we report the cell growth and functional behavior of SCs on β-tricalcium phosphate (β-TCP) scaffolds arranged in 3D printed-lattice (P-β-TCP) and randomly-porous, template-casted (N-β-TCP) structures. Our results indicate that SCs proliferated well and expressed the phenotypic markers p75LNGFR and the S100-β subunit of SCs as well as displayed growth morphology on both scaffolds, but SCs showed spindle-shaped morphology with a significant degree of SCs alignment on the P-β-TCP scaffolds, seen to a lesser degree in the N-β-TCP scaffold. The gene expressions of nerve growth factor (β-ngf), neutrophin–3 (nt–3), platelet-derived growth factor (pdgf-bb), and vascular endothelial growth factor (vegf-a) were higher at day 7 than at day 14. While no significant differences in protein secretion were measured between these last two time points, the scaffolds promoted the protein secretion at day 3 compared to that on the cell culture plates. These results together imply that the β-TCP scaffolds can support SC cell growth and that the 3D-printed scaffold appeared to significantly promote the alignment of SCs along the struts. Further studies are needed to investigate the early and late stage relationship between gene expression and protein secretion of SCs on the scaffolds with refined characteristics, thus better exploring the potential of SCs to support vascularization and innervation in synthetic bone grafts. PMID:26444999

  13. Recurrent laryngeal nerve regeneration using an oriented collagen scaffold containing Schwann cells.

    Science.gov (United States)

    Chitose, Shun-Ichi; Sato, Kiminori; Fukahori, Mioko; Sueyoshi, Shintaro; Kurita, Takashi; Umeno, Hirohito

    2017-07-01

    Regeneration of the recurrent laryngeal nerve (RLN), which innervates the intrinsic laryngeal muscles such that they can perform complex functions, is particularly difficult to achieve. Synkinesis after RLN neogenesis leads to uncoordinated movement of laryngeal muscles. Recently, some basic research studies have used cultured Schwann cells (SCs) to repair peripheral nerve injuries. This study aimed to regenerate the RLN using an oriented collagen scaffold containing cultured SCs. Preliminary animal experiment. A 10-mm-long autologous canine cervical ansa was harvested. The nerve tissue was scattered and subcultured on oriented collagen sheets in reduced serum medium. After verifying that the smaller cultivated cells with high nucleus-cytoplasm ratios were SCs, collagen sheets with longitudinally oriented cells were rolled and inserted into a 20-mm collagen conduit. The fabricated scaffolds containing SCs were autotransplanted to a 20-mm deficient RLN, and vocal fold movements and histological characteristics were observed. Scaffolds containing cultured SCs were successfully fabricated. Immunocytochemical examination revealed that these isolated and cultured cells, identified as SCs, expressed S-100 protein and GFAP but not vimentin. The orientation of SCs matched that of the oriented collagen sheet. Two months after successful transplantation, laryngeal endoscopy revealed coordinated movement of the bilateral vocal folds by external stimulation under light general anesthesia. Hematoxylin and eosin staining showed that the regenerated RLN lacked epineurium surrounding the nerve fibers and was interspersed with collagen fibers. Myelin protein zero was expressed around many axons. Partial regeneration of RLN was achieved through the use of oriented collagen scaffolding. NA Laryngoscope, 127:1622-1627, 2017. © 2016 The American Laryngological, Rhinological and Otological Society, Inc.

  14. Efficacy of Schwann cell transplantation for spinal cord repair is improved with combinatorial strategies.

    Science.gov (United States)

    Bunge, Mary Bartlett

    2016-07-01

    When cells (including Schwann cells; SCs) of the peripheral nervous system (PNS) could be purified and expanded in number in tissue culture, Richard Bunge in 1975 envisioned that the SCs could be introduced to repair the central nervous system (CNS), as SCs enable axons to regenerate after PNS injury. Importantly, autologous human SCs could be transplanted into injured human spinal cord. Availability of the new culture systems to study interactions between sensory neurons, SCs and fibroblasts increased our knowledge of SC biology in the 1970s and '80s. Joining the Miami Project to Cure Paralysis in 1989 brought the opportunity to use this knowledge to initiate spinal cord repair studies. Development of a rat complete spinal cord transection/SC bridge model allowed the demonstration that axons regenerate into the SC bridge. Together with study of contused rat spinal cord, it was concluded that implanted SCs reduce cavitation, protect tissue around the lesion, support axon regeneration and form myelin. SC transplantation efficacy was improved when combined with neurotrophins, elevation of cyclic AMP levels, olfactory ensheathing cells, a steroid or chondroitinase. Increased efficacy meant higher numbers of axons, particularly from the brainstem, and more SC-myelinated axons in the implants and improvement in hindlimb movements. Human SCs support axon regeneration as do rat SCs. Astrocytes at the SC bridge-host spinal cord interfaces play a key role in determining whether axons enter the SC milieu. The SC work described here contributed to gaining approval from the FDA for an initial autologous human SC clinical trial (at the Miami Project) that has been completed and found to be safe.

  15. Schwann cell transplantation improves reticulospinal axon growth and forelimb strength after severe cervical spinal cord contusion.

    Science.gov (United States)

    Schaal, S M; Kitay, B M; Cho, K S; Lo, T P; Barakat, D J; Marcillo, A E; Sanchez, A R; Andrade, C M; Pearse, D D

    2007-01-01

    Schwann cell (SC) implantation alone has been shown to promote the growth of propriospinal and sensory axons, but not long-tract descending axons, after thoracic spinal cord injury (SCI). In the current study, we examined if an axotomy close to the cell body of origin (so as to enhance the intrinsic growth response) could permit supraspinal axons to grow onto SC grafts. Adult female Fischer rats received a severe (C5) cervical contusion (1.1 mm displacement, 3 KDyn). At 1 week postinjury, 2 million SCs ex vivo transduced with lentiviral vector encoding enhanced green fluorescent protein (EGFP) were implanted within media into the injury epicenter; injury-only animals served as controls. Animals were tested weekly using the BBB score for 7 weeks postimplantation and received at end point tests for upper body strength: self-supported forelimb hanging, forearm grip force, and the incline plane. Following behavioral assessment, animals were anterogradely traced bilaterally from the reticular formation using BDA-Texas Red. Stereological quantification revealed a twofold increase in the numbers of preserved NeuN+ neurons rostral and caudal to the injury/graft site in SC implanted animals, corroborating previous reports of their neuroprotective efficacy. Examination of labeled reticulospinal axon growth revealed that while rarely an axon was present within the lesion site of injury-only controls, numerous reticulospinal axons had penetrated the SC implant/lesion milieu. This has not been observed following implantation of SCs alone into the injured thoracic spinal cord. Significant behavioral improvements over injury-only controls in upper limb strength, including an enhanced grip strength (a 296% increase) and an increased self-supported forelimb hanging, accompanied SC-mediated neuroprotection and reticulospinal axon growth. The current study further supports the neuroprotective efficacy of SC implants after SCI and demonstrates that SCs alone are capable of supporting

  16. Schwann cell autophagy counteracts the onset and chronification of neuropathic pain.

    Science.gov (United States)

    Marinelli, Sara; Nazio, Francesca; Tinari, Antonella; Ciarlo, Laura; D'Amelio, Marcello; Pieroni, Luisa; Vacca, Valentina; Urbani, Andrea; Cecconi, Francesco; Malorni, Walter; Pavone, Flaminia

    2014-01-01

    Axonal degeneration in peripheral nerves after injury is accompanied by myelin degradation initiated by Schwann cells (SCs). These cells activate autophagy, a ubiquitous cytoprotective process essential for degradation and recycling of cellular constituents. Concomitantly to nerve insult and axonal degeneration, neuropathic pain (NeP) arises. The role of SC autophagy in the mechanisms underlying NeP is still unknown. In this study, we examined the role of the autophagy during the early phase of Wallerian degeneration in NeP induction and chronification by using a murine model of peripheral nerve lesion (chronic constriction injury). We demonstrate that the autophagy inducer rapamycin, administered in the first week after nerve damage, induces long-lasting analgesic and antiinflammatory effects, facilitates nerve regeneration, and prevents pain chronification. Conversely, when autophagy is altered, by means of autophagic inhibitor 3-methyladenine administration or as occurs in activating molecule in Beclin-1-regulated autophagy transgenic mice (Ambra1(+/gt)), NeP is dramatically enhanced and prolonged. Immunohistochemical and ultrastructural evaluations show that rapamycin is able to increase autophagic flux in SCs, to accelerate myelin compaction, and to reduce inflammatory and immune reaction. Proteomic analysis combined with bioinformatic analysis suggests that a redox-sensitive mechanism could be responsible for SC autophagy activation. These data suggest that a deficiency of autophagic activity in SCs can be an early event in the origin of NeP chronification and that autophagy modulation may represent a powerful pharmacological approach to prevent the onset and chronification of NeP in the clinical setting.

  17. Schwann-like cells seeded in acellular nerve grafts improve nerve regeneration.

    Science.gov (United States)

    Fan, Lihong; Yu, Zefeng; Li, Jia; Dang, Xiaoqian; Wang, Kunzheng

    2014-05-21

    This study evaluated whether Schwann-like cells (SLCs) induced from bone marrow-derived mesenchymal stem cells (BM-MSCs) transplanted into acellular nerve grafts (ANGs) could repair nerve defects compared with nerve isografts and ANGs with BM-MSCs. BM-MSCs extracted, separated and purified from the bone marrow of rats, and some of the BM-MSCs were cultured with mixed induction agents that could induce BM-MSCs into SLCs. Either SLCs or BM-MSCs were seeded onto 10-mm ANGs, and the isografts were chosen as the control. The walking-track test, tibialis anterior muscle weight measurement, electrophysiological examination, toluidine blue staining, transmission electron micrographs and immunostaining of S-100 and VEGF in these three groups were evaluated in a 10-mm rat sciatic injury-repair model. The walking-track test, tibialis anterior muscle weight measurement and electrophysiological examination of the sciatic nerve suggested the groups of ANGs with SLCs and isografts obtained better results than the BM-MSC group (P0.05). All the histomorphometric analyses (toluidine blue staining, transmission electron micrographs and immunostaining of S-100 and VEGF) showed that there were more regenerating nerve fibers in the group of ANGs with SLCs than the BM-MSCs (P0.05). SLCs seeded in ANGs and isografts show better functional regeneration compared with BM-MSCs seeded in ANGs. Additionally, SLCs combined with ANGs present almost the same outcome as the isografts. Therefore, SLCs with ANGs can be a good choice in nerve defect repairs.

  18. Expression of activating transcription factor 3 (ATF 3) and caspase 3 in Schwann cells and axonal outgrowth after sciatic nerve repair in diabetic BB rats.

    Science.gov (United States)

    Stenberg, Lena; Kanje, Martin; Dolezal, Katarina; Dahlin, Lars B

    2012-04-25

    The aim of this study was to evaluate nerve regeneration in relation to the transcription factor, Activating Transcription Factor 3 (ATF 3), and an apoptotic marker, caspase 3, in the Schwann cells of diabetic BB rats (i.e. display type 1 diabetes phenotype). Sciatic nerves in healthy Wistar rats and in diabetic BB rats were transected and immediately repaired. Axonal outgrowth (neurofilament staining) and expression of ATF 3 and caspase 3 were quantified by immunohistochemistry after six days. There was no difference in axonal outgrowth between healthy and diabetic rats. However, the sciatic nerve in the diabetic rats exhibited a larger number of ATF 3 expressing Schwann cells at the site of the lesion and also a higher number of caspase 3 expressing Schwann cells. Similar differences were observed in the distal nerve segment between the healthy and diabetic rats. There were no correlations between the number of Schwann cells expressing ATF 3 and caspase 3. Thus, diabetic BB rats display an increased activation of ATF 3 and also a rise in apoptotic caspase 3 expressing Schwann cells, but with no discrepancy in length of axonal outgrowth after nerve injury and repair at six days. Knowledge about signal transduction mechanisms in diabetes after stress may provide new insights into the development of diabetic neuropathy and neuropathic pain. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  19. Netrin-1 induces the migration of Schwann cells via p38 MAPK and PI3K-Akt signaling pathway mediated by the UNC5B receptor

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    Lv, Jianwei [General Hospital of Tianjin Medical University, No. 154, Anshan Road, Heping District, Tianjin 300052 (China); Tianjin Institute of Orthopedics in Traditional Chinese and Western Medicine, No. 155, Munan Road, Tianjin 300050 (China); Sun, Xiaolei; Ma, Jianxiong [Tianjin Institute of Orthopedics in Traditional Chinese and Western Medicine, No. 155, Munan Road, Tianjin 300050 (China); Ma, Xinlong, E-mail: gengxiao502@163.com [General Hospital of Tianjin Medical University, No. 154, Anshan Road, Heping District, Tianjin 300052 (China); Tianjin Institute of Orthopedics in Traditional Chinese and Western Medicine, No. 155, Munan Road, Tianjin 300050 (China); Zhang, Yang; Li, Fengbo; Li, Yanjun; Zhao, Zhihu [Tianjin Institute of Orthopedics in Traditional Chinese and Western Medicine, No. 155, Munan Road, Tianjin 300050 (China)

    2015-08-14

    Schwann cells (SCs) play an essentially supportive role in the regeneration of injured peripheral nerve system (PNS). As Netrin-1 is crucial for the normal development of nervous system (NS) and can direct the process of damaged PNS regeneration, our study was designed to determine the role of Netrin-1 in RSC96 Schwann cells (an immortalized rat Schwann cell line) proliferation and migration. Our studies demonstrated that Netrin-1 had no effect on RSC96 cells proliferation, while significantly promoted RSC96 cells migration. The Netrin-1-induced RSC96 cells migration was significantly attenuated by inhibition of p38 and PI3K through pretreatment with SB203580 and LY294002 respectively, but not inhibition of MEK1/2 and JNK by U0126-EtOH and SP600125 individually. Treatment with Netrin-1 enhanced the phosphorylation of p38 and Akt. QRT-PCR indicated that Netrin-1 and only its receptors Unc5a, Unc5b and Neogenin were expressed in RSC96 cells, among which Unc5b expressed the most. And UNC5B protein was significantly increased after stimulated by Netrin-1. In conclusion, we show here that Netrin-1-enhanced SCs migration is mediated by activating p38 MAPK and PI3K-Akt signal cascades via receptor UNC5B, which suggests that Netrin-1 could serve as a new therapeutic strategy and has potential application value for PNS regeneration. - Highlights: • Netrin-1 attracts RSC96 Schwann cells migration in a dose dependent manner. • Netrin-1 induced Schwann cells migration is p38 and PI3K-Akt signaling dependent. • UNC5B may be dominant receptor mediating Netrin-1′ effect on RSC96 cells motility. • Netrin-1 may promote peripheral nerve repair by enhancing Schwann cells motility.

  20. Effect of Delayed Peripheral Nerve Repair on Nerve Regeneration, Schwann Cell Function and Target Muscle Recovery

    Science.gov (United States)

    Jonsson, Samuel; Wiberg, Rebecca; McGrath, Aleksandra M.; Novikov, Lev N.; Wiberg, Mikael; Novikova, Liudmila N.; Kingham, Paul J.

    2013-01-01

    Despite advances in surgical techniques for peripheral nerve repair, functional restitution remains incomplete. The timing of surgery is one factor influencing the extent of recovery but it is not yet clearly defined how long a delay may be tolerated before repair becomes futile. In this study, rats underwent sciatic nerve transection before immediate (0) or 1, 3, or 6 months delayed repair with a nerve graft. Regeneration of spinal motoneurons, 13 weeks after nerve repair, was assessed using retrograde labeling. Nerve tissue was also collected from the proximal and distal stumps and from the nerve graft, together with the medial gastrocnemius (MG) muscles. A dramatic decline in the number of regenerating motoneurons and myelinated axons in the distal nerve stump was observed in the 3- and 6-months delayed groups. After 3 months delay, the axonal number in the proximal stump increased 2–3 folds, accompanied by a smaller axonal area. RT-PCR of distal nerve segments revealed a decline in Schwann cells (SC) markers, most notably in the 3 and 6 month delayed repair samples. There was also a progressive increase in fibrosis and proteoglycan scar markers in the distal nerve with increased delayed repair time. The yield of SC isolated from the distal nerve segments progressively fell with increased delay in repair time but cultured SC from all groups proliferated at similar rates. MG muscle at 3- and 6-months delay repair showed a significant decline in weight (61% and 27% compared with contra-lateral side). Muscle fiber atrophy and changes to neuromuscular junctions were observed with increased delayed repair time suggestive of progressively impaired reinnervation. This study demonstrates that one of the main limiting factors for nerve regeneration after delayed repair is the distal stump. The critical time point after which the outcome of regeneration becomes too poor appears to be 3-months. PMID:23409189

  1. A guidance channel seeded with autologous Schwann cells for repair of cauda equina injury in a primate model.

    Science.gov (United States)

    Calancie, Blair; Madsen, Parley W; Wood, Patrick; Marcillo, Alexander E; Levi, Allan D; Bunge, Richard P

    2009-01-01

    To evaluate an implantable guidance channel (GC) seeded with autologous Schwann cells to promote regeneration of transected spinal nerve root axons in a primate model. Schwann cells were obtained from sural nerve segments of monkeys (Macaca fascicularis; cynomolgus). Cells were cultured, purified, and seeded into a PAN/PVC GC. Approximately 3 weeks later, monkeys underwent laminectomy and dural opening. Nerve roots of the L4 through L7 segments were identified visually. The threshold voltage needed to elicit hindlimb muscle electromyography (EMG) after stimulation of intact nerve roots was determined. Segments of 2 or 3 nerve roots (each approximately 8-15 mm in length) were excised. The GC containing Schwann cells was implanted between the proximal and distal stumps of these nerve roots and attached to the stumps with suture. Follow-up evaluation was conducted on 3 animals, with survival times of 9 to 14 months. Upon reexposure of the implant site, subdural nerve root adhesions were noted in all 3 animals. Several of the implanted GC had collapsed and were characterized by thin strands of connective tissue attached to either end. In contrast, 3 of the 8 implanted GC were intact and had white, glossy cables entering and exiting the conduits. Electrical stimulation of the tissue cable in each of these 3 cases led to low-threshold evoked EMG responses, suggesting that muscles had been reinnervated by axons regenerating through the repair site and into the distal nerve stump. During harvesting of the GC implant, sharp transection led to spontaneous EMG in the same 3 roots showing a low threshold to electrical stimulation, whereas no EMG was seen when harvesting nerve roots with high thresholds to elicit EMG. Histology confirmed large numbers of myelinated axons at the midpoint of 2 GC judged to have reinnervated target muscles. We found a modest rate of successful regeneration and muscle reinnervation after treatment of nerve root transection with a Schwann cell

  2. The Use of Autologous Schwann Cells to Supplement Sciatic Nerve Repair With a Large Gap: First in Human Experience.

    Science.gov (United States)

    Levi, Allan D; Burks, S Shelby; Anderson, Kim D; Dididze, Marine; Khan, Aisha; Dietrich, W Dalton

    Insufficient donor nerve graft material in peripheral nerve surgery remains an obstacle for successful long-distance regeneration. Schwann cells (SCs) can be isolated from adult mammalian peripheral nerve biopsies and can be grown in culture and retain their capacity to enhance peripheral nerve regeneration within tubular repair strategies in multiple animal models. Human Schwann cells (hSCs) can be isolated, expanded in number, and retain their ability to promote regeneration and myelinate axons, but have never been tested in a clinical case of peripheral nerve injury. A sural nerve biopsy and peripheral nerve tissue from the traumatized sciatic nerve stumps was obtained after Food and Drug Administration (FDA) and Institutional Review Board (IRB) approval as well as patient consent. The SCs were isolated after enzymatic digestion of the nerve and expanded with the use of heregulin β1 (0.1 µg/ml) and forskolin (15 mM). After two passages the Schwann cell isolates were combined with sural nerve grafts to repair a large sciatic nerve defect (7.5 cm) after a traumatic nerve injury. The sural nerve and the traumatized sciatic nerve ends both served as an excellent source of purified (90% and 97%, respectively) hSCs. Using ultrasound and magnetic resonance imaging (MRI) we were able to determine continuity of the nerve graft repair and the absence of tumor formation. The patient had evidence of proximal sensory recovery and definitive motor recovery distal to the repair in the distribution of the tibial and common peroneal nerve. The patient did experience an improvement in her pain scores over time. The goals of this approach were to determine the safety and clinical feasibility of implementing a new cellular repair strategy. In summary, this approach represents a novel strategy in the treatment of peripheral nerve injury and represents the first reported use of autologous cultured SCs after human peripheral nerve injury.

  3. G-CSF prevents caspase 3 activation in Schwann cells after sciatic nerve transection, but does not improve nerve regeneration.

    Science.gov (United States)

    Frost, Hanna K; Kodama, Akira; Ekström, Per; Dahlin, Lars B

    2016-10-15

    Exogenous granulocyte-colony stimulating factor (G-CSF) has emerged as a drug candidate for improving the outcome after peripheral nerve injuries. We raised the question if exogenous G-CSF can improve nerve regeneration following a clinically relevant model - nerve transection and repair - in healthy and diabetic rats. In short-term experiments, distance of axonal regeneration and extent of injury-induced Schwann cell death was quantified by staining for neurofilaments and cleaved caspase 3, respectively, seven days after repair. There was no difference in axonal outgrowth between G-CSF-treated and non-treated rats, regardless if healthy Wistar or diabetic Goto-Kakizaki (GK) rats were examined. However, G-CSF treatment caused a significant 13% decrease of cleaved caspase 3-positive Schwann cells at the lesion site in healthy rats, but only a trend in diabetic rats. In the distal nerve segments of healthy rats a similar trend was observed. In long-term experiments of healthy rats, regeneration outcome was evaluated at 90days after repair by presence of neurofilaments, wet weight of gastrocnemius muscle, and perception of touch (von Frey monofilament testing weekly). The presence of neurofilaments distal to the suture line was similar in G-CSF-treated and non-treated rats. The weight ratio of ipsi-over contralateral gastrocnemius muscles, and perception of touch at any time point, were likewise not affected by G-CSF treatment. In addition, the inflammatory response in short- and long-term experiments was studied by analyzing ED1 stainable macrophages in healthy rats, but in neither case was any attenuation seen at the injury site or distal to it. G-CSF can prevent caspase 3 activation in Schwann cells in the short-term, but does not detectably affect the inflammatory response, nor improve early or late axonal outgrowth or functional recovery.

  4. Association of Myosin Va and Schwann cells-derived RNA in mammal myelinated axons, analyzed by immunocytochemistry and confocal FRET microscopy.

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    Canclini, Lucía; Wallrabe, Horst; Di Paolo, Andrés; Kun, Alejandra; Calliari, Aldo; Sotelo-Silveira, José Roberto; Sotelo, José Roberto

    2014-03-15

    Evidence from multiple sources supports the hypothesis that Schwann cells in the peripheral nervous system transfer messenger RNA and ribosomes to the axons they ensheath. Several technical and methodological difficulties exist for investigators to unravel this process in myelinated axons - a complex two-cell unit. We present an experimental design to demonstrate that newly synthesized RNA is transferred from Schwann cells to axons in association with Myosin Va. The use of quantitative confocal FRET microscopy to track newly-synthesized RNA and determine the molecular association with Myosin Va, is described in detail.

  5. Schwann cell expressed Nogo-B modulates axonal branching of adult sensory neurons through the Nogo-B receptor NgBR

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    Christoph eEckharter

    2015-11-01

    Full Text Available In contrast to the central nervous system (CNS nerve fibers do regenerate in the peripheral nervous system (PNS although in a clinically unsatisfying manner. A major problem is excessive sprouting of regenerating axons which results in aberrant reinnervation of target tissue and impaired functional recovery. In the CNS, the reticulon protein Nogo-A has been identified as a prominent oligodendrocyte expressed inhibitor of long-distance growth of regenerating axons. We show here that the related isoform Nogo-B is abundantly expressed in Schwann cells in the PNS. Other than Nogo-A in oligodendrocytes, Nogo-B does not localize to the myelin sheath but is detected in the ER and the plasma membrane of Schwann cells. Adult sensory neurons that are cultured on nogo-a/b deficient Schwann cells form significantly fewer axonal branches versus those on wildtype Schwann cells, while their maximal axonal extension is unaffected. We demonstrate that this effect of Nogo-B on neuronal morphology is restricted to undifferentiated Schwann cells and is mediated by direct physical contact between these two cell types. Moreover, we show that blocking the Nogo-B specific receptor NgBR, which we find expressed on sensory neurons and to interact with Schwann cell expressed Nogo-B, produces the same branching phenotype as observed after deletion of Nogo-B. These data provide evidence for a novel function of the nogo gene that is implemented by the Nogo-B isoform. The remarkably specific effects of Nogo-B/ NgBR on axonal branching, while leaving axonal extension unaffected, are of potential clinical relevance in the context of excessive axonal sprouting after peripheral nerve injury.

  6. Macrophage-derived microvesicles promote proliferation and migration of Schwann cell on peripheral nerve repair

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    Zhan, Chuan, E-mail: zhchuansy@163.com; Ma, Cheng-bin; Yuan, Hong-mou; Cao, Bao-yuan; Zhu, Jia-jun

    2015-12-04

    Background: Macrophages have been implicated in peripheral nerve regeneration. However, whether macrophages-derived microvesicles (MVs) are involved in this process remains unknown. In the present study, the effects of macrophages-derived MVs on proliferation and migration of Schwann cells (SCs) were evaluated in both in vitro and in vivo. Methods: Human monocytic leukaemia cell line (THP-1) was successfully driven to M1 and M2 phenotypes by delivery of either IFN-γ or IL-4, respectively. SCs incubated with M1 or M2 macrophages-derived MVs, the cell migration and proliferation were assessed, and expression levels of nerve growth factor (NGF) and Laminin were measured. A rat model of sciatic nerve was established and the effects of macrophages-derived MVs on nerve regeneration were investigated. Results: M2-derived MVs elevated migration, proliferation, NFG and Laminin protein levels of SCs compared with M1-or M0-derived MVs. The relative expression levels of miR-223 were also increased in M2 macrophages and M2-derived MVs. Transfected M2 macrophages with miR-223 inhibitor then co-incubated with SCs, an inhibition of cell migration and proliferation and a down-regulated levels of NFG and Laminin protein expression were observed. In vivo, M2-derived MVs significantly increased the infiltration and axon number of SCs. Conclusion: M2-derived MVs promoted proliferation and migration of SCs in vitro and in vivo, which provided a therapeutic strategy for nerve regeneration. - Highlights: • M2 macrophages-derived MVs elevated migration and proliferation of SCs. • M2 macrophages-derived MVs up-regulated NFG and Laminin expression of SCs. • MiR-223 expression was increased in M2 macrophages-derived MVs. • MiR-223 inhibitor reduced migration and proliferation of SCs co-incubated with MVs. • MiR-223 inhibitor down-regulated NFG and Laminin levels of SCs co-incubated with MVs.

  7. Activation of Schwann cells in vitro by magnetic nanocomposites via applied magnetic field.

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    Liu, Zhongyang; Huang, Liangliang; Liu, Liang; Luo, Beier; Liang, Miaomiao; Sun, Zhen; Zhu, Shu; Quan, Xin; Yang, Yafeng; Ma, Teng; Huang, Jinghui; Luo, Zhuojing

    2015-01-01

    Schwann cells (SCs) are attractive seed cells in neural tissue engineering, but their application is limited by attenuated biological activities and impaired functions with aging. Therefore, it is important to explore an approach to enhance the viability and biological properties of SCs. In the present study, a magnetic composite made of magnetically responsive magnetic nanoparticles (MNPs) and a biodegradable chitosan-glycerophosphate polymer were prepared and characterized. It was further explored whether such magnetic nanocomposites via applied magnetic fields would regulate SC biological activities. The magnetization of the magnetic nanocomposite was measured by a vibrating sample magnetometer. The compositional characterization of the magnetic nanocomposite was examined by Fourier-transform infrared and X-ray diffraction. The tolerance of SCs to the magnetic fields was tested by flow-cytometry assay. The proliferation of cells was examined by a 5-ethynyl-2-deoxyuridine-labeling assay, a PrestoBlue assay, and a Live/Dead assay. Messenger ribonucleic acid of BDNF, GDNF, NT-3, and VEGF in SCs was assayed by quantitative real-time polymerase chain reaction. The amount of BDNF, GDNF, NT-3, and VEGF secreted from SCs was determined by enzyme-linked immunosorbent assay. It was found that magnetic nanocomposites containing 10% MNPs showed a cross-section diameter of 32.33±1.81 µm, porosity of 80.41%±0.72%, and magnetization of 5.691 emu/g at 8 kOe. The 10% MNP magnetic nanocomposites were able to support cell adhesion and spreading and further promote proliferation of SCs under magnetic field exposure. Interestingly, a magnetic field applied through the 10% MNP magnetic scaffold significantly increased the gene expression and protein secretion of BDNF, GDNF, NT-3, and VEGF. This work is the first stage in our understanding of how to precisely regulate the viability and biological properties of SCs in tissue-engineering grafts, which combined with additional

  8. Synaptic development in the injured spinal cord cavity following co-transplantation of fetal spinal cord cells and autologous activated Schwann cells

    Institute of Scientific and Technical Information of China (English)

    Wendong Ruan; Yuan Xue; Ninghua Li; Xiaotao Zhao; Huajian Zhao; Peng Li

    2010-01-01

    Transplantation of activated transgenic Schwann cells or a fetal spinal cord cell suspension has been widely used to treat spinal cord injury. However, little is known regarding the effects of co-transplantation. In the present study, autologous Schwann cells in combination with a fetal spinal cord cell suspension were transplanted into adult Wistar rats with spinal cord injury, and newly generated axonal connections were observed ultrastructurally. Transmission electron microscopic observations showed that the neuroblast first presented cytoplasmic processes, followed by pre- and postsynaptic membranes with low electron density forming a dense projection. The number and types of synaptic vesicles were increased. Synaptic connections developed from single cell body-dendritic synapses into multiple cell body-dendritic anddendrite-dendritic synapses. In addition, the cell organs of the transplanted neuroblast, oligodendroblast and astroblast matured gradually. The blood-brain barrier appeared subsequently. Moreover, neurofilament, histamine, calcitonin-gene-related peptides, and glial fibrillary acidic protein positive fibers were observed in the transplant region. These findings demonstrate that fetal spinal cord cells in the presence of autologous activated Schwann cells can develop into mature synapses in the cavity of injured spinal cords, suggesting the possibility of information exchange through the reconstructed synapse between fetal spinal cord cells and the host.

  9. Requirement of cAMP signaling for Schwann cell differentiation restricts the onset of myelination.

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    Bacallao, Ketty; Monje, Paula V

    2015-01-01

    Isolated Schwann cells (SCs) respond to cAMP elevation by adopting a differentiated post-mitotic state that exhibits high levels of Krox-20, a transcriptional enhancer of myelination, and mature SC markers such as the myelin lipid galactocerebroside (O1). To address how cAMP controls myelination, we performed a series of cell culture experiments which compared the differentiating responses of isolated and axon-related SCs to cAMP analogs and ascorbate, a known inducer of axon ensheathment, basal lamina formation and myelination. In axon-related SCs, cAMP induced the expression of Krox-20 and O1 without a concomitant increase in the expression of myelin basic protein (MBP) and without promoting axon ensheathment, collagen synthesis or basal lamina assembly. When cAMP was provided together with ascorbate, a dramatic enhancement of MBP expression occurred, indicating that cAMP primes SCs to form myelin only under conditions supportive of basal lamina formation. Experiments using a combination of cell permeable cAMP analogs and type-selective adenylyl cyclase (AC) agonists and antagonists revealed that selective transmembrane AC (tmAC) activation with forskolin was not sufficient for full SC differentiation and that the attainment of an O1 positive state also relied on the activity of the soluble AC (sAC), a bicarbonate sensor that is insensitive to forskolin and GPCR activation. Pharmacological and immunological evidence indicated that SCs expressed sAC and that sAC activity was required for morphological differentiation and the expression of myelin markers such as O1 and protein zero. To conclude, our data indicates that cAMP did not directly drive myelination but rather the transition into an O1 positive state, which is perhaps the most critical cAMP-dependent rate limiting step for the onset of myelination. The temporally restricted role of cAMP in inducing differentiation independently of basal lamina formation provides a clear example of the uncoupling of signals

  10. Requirement of cAMP signaling for Schwann cell differentiation restricts the onset of myelination.

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    Ketty Bacallao

    Full Text Available Isolated Schwann cells (SCs respond to cAMP elevation by adopting a differentiated post-mitotic state that exhibits high levels of Krox-20, a transcriptional enhancer of myelination, and mature SC markers such as the myelin lipid galactocerebroside (O1. To address how cAMP controls myelination, we performed a series of cell culture experiments which compared the differentiating responses of isolated and axon-related SCs to cAMP analogs and ascorbate, a known inducer of axon ensheathment, basal lamina formation and myelination. In axon-related SCs, cAMP induced the expression of Krox-20 and O1 without a concomitant increase in the expression of myelin basic protein (MBP and without promoting axon ensheathment, collagen synthesis or basal lamina assembly. When cAMP was provided together with ascorbate, a dramatic enhancement of MBP expression occurred, indicating that cAMP primes SCs to form myelin only under conditions supportive of basal lamina formation. Experiments using a combination of cell permeable cAMP analogs and type-selective adenylyl cyclase (AC agonists and antagonists revealed that selective transmembrane AC (tmAC activation with forskolin was not sufficient for full SC differentiation and that the attainment of an O1 positive state also relied on the activity of the soluble AC (sAC, a bicarbonate sensor that is insensitive to forskolin and GPCR activation. Pharmacological and immunological evidence indicated that SCs expressed sAC and that sAC activity was required for morphological differentiation and the expression of myelin markers such as O1 and protein zero. To conclude, our data indicates that cAMP did not directly drive myelination but rather the transition into an O1 positive state, which is perhaps the most critical cAMP-dependent rate limiting step for the onset of myelination. The temporally restricted role of cAMP in inducing differentiation independently of basal lamina formation provides a clear example of the

  11. Schwann cells but not olfactory ensheathing cells inhibit CNS myelination via the secretion of connective tissue growth factor.

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    Lamond, Rebecca; Barnett, Susan C

    2013-11-20

    Cell transplantation is a promising strategy to promote CNS repair and has been studied for several decades with a focus on glial cells. Promising candidates include Schwann cells (SCs) and olfactory ensheathing cells (OECs). Both cell types are thought to be neural crest derived and share many properties in common, although OECs appear to be a better candidate for transplantation by evoking less astrogliosis. Using CNS mixed myelinating rat cultures plated on to a monolayer of astrocytes, we demonstrated that SCs, but not OECs, secrete a heat labile factor(s) that inhibits oligodendrocyte myelination. Comparative qRT-PCR and ELISA showed that SCs expressed higher levels of mRNA and protein for connective tissue growth factor (CTGF) than OECs. Anti-CTGF reversed the SCM-mediated effects on myelination. Both SCM and CTGF inhibited the differentiation of purified rat oligodendrocyte precursor cells (OPCs). Furthermore, pretreatment of astrocyte monolayers with SCM inhibited CNS myelination and led to transcriptional changes in the astrocyte, corresponding to upregulation of bone morphogenic protein 4 mRNA and CTGF mRNA (inhibitors of OPC differentiation) and the downregulation of insulin-like growth factor 2 mRNA (promoter of OPC differentiation). CTGF pretreatment of astrocytes increased their expression of CTGF, suggesting that this inhibitory factor can be positively regulated in astrocytes. These data provide evidence for the advantages of using OECs, and not mature SCs, for transplant-mediated repair and provide more evidence that they are a distinct and unique glial cell type.

  12. Rat Nasal Respiratory Mucosa-Derived Ectomesenchymal Stem Cells Differentiate into Schwann-Like Cells Promoting the Differentiation of PC12 Cells and Forming Myelin In Vitro

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    Jian Zhang

    2015-01-01

    Full Text Available Schwann cell (SC transplantation as a cell-based therapy can enhance peripheral and central nerve repair experimentally, but it is limited by the donor site morbidity for clinical application. We investigated weather respiratory mucosa stem cells (REMSCs, a kind of ectomesenchymal stem cells (EMSCs, isolated from rat nasal septum can differentiate into functional Schwann-like cells (SC-like cells. REMSCs proliferated quickly in vitro and expressed the neural crest markers (nestin, vimentin, SOX10, and CD44. Treated with a mixture of glial growth factors for 7 days, REMSCs differentiated into SC-like cells. The differentiated REMSCs (dREMSCs exhibited a spindle-like morphology similar to SC cells. Immunocytochemical staining and Western blotting indicated that SC-like cells expressed the glial markers (GFAP, S100β, Galc, and P75 and CNPase. When cocultured with dREMSCs for 5 days, PC12 cells differentiated into mature neuron-like cells with long neurites. More importantly, dREMSCs could form myelin structures with the neurites of PC12 cells at 21 days in vitro. Our data indicated that REMSCs, a kind of EMSCs, could differentiate into SC-like cells and have the ability to promote the differentiation of PC12 cells and form myelin in vitro.

  13. CAP1 was associated with actin and involved in Schwann cell differentiation and motility after sciatic nerve injury.

    Science.gov (United States)

    Zhu, Xinhui; Yao, Li; Guo, Aisong; Li, Aihong; Sun, Huiqing; Wang, Ning; Liu, Hanzhang; Duan, Zhiqin; Cao, Jianhua

    2014-06-01

    Adenylate cyclase-associated protein 1 (CAP1), a member of cyclase-associated proteins that regulating actin dynamics, was shown to regulate actin filaments, localize to dynamic actin structures and mediate such processes as establishment of cell polarity, motility, morphogenesis, receptor-mediated endocytosis and mRNA location. But little is known about the role of CAP1 during peripheral nervous system injury. Here, we found the spatiotemporal protein expression of CAP1 after sciatic nerve crush. After crush, CAP1 had an increased protein expression level, reached a peak at about day 5 and then returned to the normal level at 4 weeks, similar to Oct-6. Besides, in 5-day injured tissue, using double immunofluorescent staining we found CAP1 had a colocalization with S100 and Oct-6. In vitro, during the process of cAMP-induced Schwann cells differentiation, we observed enhanced expression of CAP1 and P0. Specially, CAP1-specific siRNA-tranfected SCs did not show significant actin structure which form cellure surface tension and protrusion shape after cAMP treatment. And we observed the interaction of CAP1 with actin and that CAP1-specific siRNA-transfected SCs had a decreased motility and migration. Together, all these data indicated that the change of CAP1 protein expression was associated with Schwann cells motility and differentiation after the crush of sciatic nerve.

  14. Nerve injury induces glial cell line-derived neurotrophic factor (GDNF) expression in Schwann cells through purinergic signaling and the PKC-PKD pathway.

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    Xu, Pin; Rosen, Kenneth M; Hedstrom, Kristian; Rey, Osvaldo; Guha, Sushovan; Hart, Courtney; Corfas, Gabriel

    2013-07-01

    Upon peripheral nerve injury, specific molecular events, including increases in the expression of selected neurotrophic factors, are initiated to prepare the tissue for regeneration. However, the mechanisms underlying these events and the nature of the cells involved are poorly understood. We used the injury-induced upregulation of glial cell-derived neurotrophic factor (GDNF) expression as a tool to gain insights into these processes. We found that both myelinating and nonmyelinating Schwann cells are responsible for the dramatic increase in GDNF expression after injury. We also demonstrate that the GDNF upregulation is mediated by a signaling cascade involving activation of Schwann cell purinergic receptors, followed by protein kinase C signaling which activates protein kinase D (PKD), which leads to increased GDNF transcription. Given the potent effects of GDNF on survival and repair of injured peripheral neurons, we propose that targeting these pathways may yield therapeutic tools to treat peripheral nerve injury and neuropathies.

  15. Tonsil-Derived Mesenchymal Stem Cells Differentiate into a Schwann Cell Phenotype and Promote Peripheral Nerve Regeneration.

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    Jung, Namhee; Park, Saeyoung; Choi, Yoonyoung; Park, Joo-Won; Hong, Young Bin; Park, Hyun Ho Choi; Yu, Yeonsil; Kwak, Geon; Kim, Han Su; Ryu, Kyung-Ha; Kim, Jae Kwang; Jo, Inho; Choi, Byung-Ok; Jung, Sung-Chul

    2016-11-09

    Schwann cells (SCs), which produce neurotropic factors and adhesive molecules, have been reported previously to contribute to structural support and guidance during axonal regeneration; therefore, they are potentially a crucial target in the restoration of injured nervous tissues. Autologous SC transplantation has been performed and has shown promising clinical results for treating nerve injuries and donor site morbidity, and insufficient production of the cells have been considered as a major issue. Here, we performed differentiation of tonsil-derived mesenchymal stem cells (T-MSCs) into SC-like cells (T-MSC-SCs), to evaluate T-MSC-SCs as an alternative to SCs. Using SC markers such as CAD19, GFAP, MBP, NGFR, S100B, and KROX20 during quantitative real-time PCR we detected the upregulation of NGFR, S100B, and KROX20 and the downregulation of CAD19 and MBP at the fully differentiated stage. Furthermore, we found myelination of axons when differentiated SCs were cocultured with mouse dorsal root ganglion neurons. The application of T-MSC-SCs to a mouse model of sciatic nerve injury produced marked improvements in gait and promoted regeneration of damaged nerves. Thus, the transplantation of human T-MSCs might be suitable for assisting in peripheral nerve regeneration.

  16. Stem cells from human exfoliated deciduous teeth differentiate toward neural cells in a medium dynamically cultured with Schwann cells in a series of polydimethylsiloxanes scaffolds

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    Su, Wen-Ta; Pan, Yu-Jing

    2016-08-01

    Objective. Schwann cells (SCs) are primary structural and functional cells in the peripheral nervous system. These cells play a crucial role in peripheral nerve regeneration by releasing neurotrophic factors. This study evaluated the neural differentiation potential effects of stem cells from human exfoliated deciduous teeth (SHEDs) in a rat Schwann cell (RSC) culture medium. Approach. SHEDs and RSCs were individually cultured on a polydimethylsiloxane (PDMS) scaffold, and the effects of the RSC medium on the SHEDs differentiation between static and dynamic cultures were compared. Main results. Results demonstrated that the SHED cells differentiated by the RSC cultured medium in the static culture formed neurospheres after 7 days at the earliest, and SHED cells formed neurospheres within 3 days in the dynamic culture. These results confirm that the RSC culture medium can induce neurospheres formation, the speed of formation and the number of neurospheres (19.16 folds high) in a dynamic culture was superior to the static culture for 3 days culture. The SHED-derived spheres were further incubated in the RSCs culture medium, these neurospheres continuously differentiated into neurons and neuroglial cells. Immunofluorescent staining and RT-PCR revealed nestin, β-III tubulin, GFAP, and γ-enolase of neural markers on the differentiated cells. Significance. These results indicated that the RSC culture medium can induce the neural differentiation of SHED cells, and can be used as a new therapeutic tool to repair nerve damage.

  17. Erythropoietin Modification Enhances the Protection of Mesenchymal Stem Cells on Diabetic Rat-Derived Schwann Cells: Implications for Diabetic Neuropathy

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    Shuyun Zhang

    2017-01-01

    Full Text Available Diabetes-triggered apoptosis of Schwann cells (SC contributes to the degradation of diabetic peripheral neuropathy (DNP. In recent years, mesenchymal stem cells (MSC were applied to DPN repair and it was demonstrated that paracrine secretion played a key role in neuroprotection exerted by MSC. Erythropoietin (EPO is a potent cytokine capable of reducing apoptosis of SC. However, the expression of EPO in MSC is limited. In this study, we hypothesized that overexpression of EPO in MSC (EPO-MSC may significantly improve their neuroprotective potentials. The EPO overexpression in MSC was achieved by lentivirus transduction. SC derived from the periphery nerve of diabetic rats were cocultured with MSC or EPO-MSC in normal or high glucose culture condition, respectively. In normal glucose culture condition, the overexpression of EPO in MSC promoted the MSC-induced restoration of SC from diabetic rats, including increases in GSH level and cell viability, decrease in TUNEL apoptosis, upregulation of antiapoptotic proteins, p-Akt, and Bcl-2, and downregulation of proapoptotic proteins, cleaved caspase-3, and Bax. The subsequent results in high glucose culture condition showed similar promotions achieved by EPO-MSC. Thus, it could be concluded that EPO-MSC possessed a potent potential in hampering apoptosis of SC, and the suppression was probably attributed to attenuating oxidative stress and regulating apoptosis related protein factors.

  18. Synergistic Effect of Schwann Cells and Retinoic Acid on Differentiation and Synaptogenesis of Hippocampal Neural Stem Cells in vitro

    Institute of Scientific and Technical Information of China (English)

    XUE-BAO ZHANG; YUAN-SHAN ZENG; WEI ZHANG; YA-YUN CHEN; WEI ZHANG; YI XIONG; SUI-JUN CHEN

    2006-01-01

    Objective To investigate the synergistic effect of Schwann cells (YCs) and retinoic acid (RA) on differentiation and synaptogenesis of neural stem cells (NSCs) derived from hippocampus of neonatal rats. Methods The classical method for 2×2 factorial analysis experiment was used to assess synergistic action of SCs and RA. NSCs were treated with RA, SCs,and SCs + RA in DMEM/F12 with 0.5% fetal bovine serum for six days, respectively. Double immunofluorescent staining was used to detect the differentiation of NSCs including nestin, glial fibrillary acidic protein (GFAP) and Map2. The expression of PSD95 was used to demonstrate synaptogenesis. Results After NSCs were treated with RA or SCs, the expression of nestin and GFAP was significantly decreased while the expression of Map2 and PSD95 was significantly increased in comparison with the control. Factorial ANOVA showed that interactions between SCs and RA could induce the expression of Map2 and PSD95. Conclusion SCs and RA could promote synergistically the neuronal differentiation and synaptogenesis of hippocampal neural stem cells in vitro while they decreased the astrocytes and nestin positive NSCs.

  19. Erythropoietin Modification Enhances the Protection of Mesenchymal Stem Cells on Diabetic Rat-Derived Schwann Cells: Implications for Diabetic Neuropathy

    Science.gov (United States)

    Zhang, Shuyun

    2017-01-01

    Diabetes-triggered apoptosis of Schwann cells (SC) contributes to the degradation of diabetic peripheral neuropathy (DNP). In recent years, mesenchymal stem cells (MSC) were applied to DPN repair and it was demonstrated that paracrine secretion played a key role in neuroprotection exerted by MSC. Erythropoietin (EPO) is a potent cytokine capable of reducing apoptosis of SC. However, the expression of EPO in MSC is limited. In this study, we hypothesized that overexpression of EPO in MSC (EPO-MSC) may significantly improve their neuroprotective potentials. The EPO overexpression in MSC was achieved by lentivirus transduction. SC derived from the periphery nerve of diabetic rats were cocultured with MSC or EPO-MSC in normal or high glucose culture condition, respectively. In normal glucose culture condition, the overexpression of EPO in MSC promoted the MSC-induced restoration of SC from diabetic rats, including increases in GSH level and cell viability, decrease in TUNEL apoptosis, upregulation of antiapoptotic proteins, p-Akt, and Bcl-2, and downregulation of proapoptotic proteins, cleaved caspase-3, and Bax. The subsequent results in high glucose culture condition showed similar promotions achieved by EPO-MSC. Thus, it could be concluded that EPO-MSC possessed a potent potential in hampering apoptosis of SC, and the suppression was probably attributed to attenuating oxidative stress and regulating apoptosis related protein factors.

  20. Proliferación y expresión de marcadores por células de Schwann de rata adulta en cultivo Schwann cells proliferation and marker expression on adult rat in culture

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    Martínez Constanza

    1999-06-01

    Full Text Available En este trabajo se evalúan diferentes técnicas para obten-ción y cultivo de células de Schwann provenientes del nervio periférico de rata adulta, de las cuales la que evi-dencia mejor respuesta es la que combina una degenera-ción walleriana durante 14 días in vitro, seguida de una disociación enzimática. La adición de mitógenos como la forskolina y extracto de pituitaria no muestra un efecto sobre estas células. Los niveles de enriquecimiento en células de Schwann, defi-nidos de acuerdo con patrones morfológicos y de expre-sión de marcadores tales como la proteína S-100 o la pro-teína acida fíbrilar glial (GFAP, son buenos (del orden de 80-88% hasta los ocho días de cultivo. La detección de bromodeoxiouridina (BrdU incorporada por células en fase S del ciclo celular, demuestra que en términos ge-nerales la tasa de incorporación de BrdU de las células guales del sistema nervioso periférico no cambia.This study evaluated some techniques for culture and growth of Schwann Cells from adult rats peripheral nerves. The best of these methods is a combination of in vitro Wallerian degeneration during 14 days, followed by an enzimatic dissociation with collagenase and dispase Mitogens like forskolin and pituitary extract do not have any effects on these cells. Enrichement of the culture (measure by morphological and inmunocitochemical criteria was about 80-88% until 8 days in culture. Stable Level of BrdU incorporation suggested that the population of cells entering S phase does not change.

  1. Sam68 promotes Schwann cell proliferation by enhancing the PI3K/Akt pathway and acts on regeneration after sciatic nerve crush

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    Wu, Weijie, E-mail: 459586768@qq.com; Liu, Yuxi, E-mail: 924013616@qq.com; Wang, Youhua, E-mail: wyouhua1516@163.com

    2016-05-13

    Sam68 (Src-associated in mitosis of 68 kD), a KH domain RNA-binding protein, is not only important in signaling transduction cascades, but crucial in a variety of cellular processes. Sam68 is reported to be involved in the phospoinositide3-kinase (PI3K) and nuclear factor-kappa B (NF-κB) signaling pathways, and it is closely associated with cell proliferation, RNA metabolism, and tumor progression. However, we know little about the role of Sam68 during peripheral nervous system injury and regeneration. In this study, we investigated the expression of Sam68 and its biological significances in sciatic nerve crush. Interestingly, we found Sam68 had a co-localization with S100 (Schwann cell marker). Moreover, after crush, Sam68 had a spatiotemporal protein expression, which was in parallel with proliferation cell nuclear antigen (PCNA). In vitro, we also observed increased expression of Sam68 during the process of TNF-α-induced Schwann cell proliferation model. Besides, flow cytometry analyses, CCK-8, and EDU were all performed with the purpose of investigating the role of Sam68 in the regulation of Schwann cell proliferation. Even more importantly, we discovered that Sam68 could enhance the phosphorylation of Akt while LY294002 (a PI3K inhibitor) obviously reversed Sam68-induced cell proliferation. Finally, we detected the variance during regeneration progress through the rat walk footprint test. In summary, all these evidences demonstrated that Sam68 might participate in Schwann cell proliferation partially via PI3K/Akt pathway and also regulate regeneration after sciatic nerve crush. -- Highlights: •The dynamic changes and location of Sam68 after sciatic nerve crush. •Sam68 promoted Schwann cell proliferation via PI3K/Akt pathway. •Sam68 modulated functional recovery after sciatic nerve crush.

  2. Combination of grafted Schwann cells and lentiviral-mediated prevention of glial scar formation improve recovery of spinal cord injured rats.

    Science.gov (United States)

    Do-Thi, Anh; Perrin, Florence E; Desclaux, Mathieu; Saillour, Paulette; Amar, Lahouari; Privat, Alain; Mallet, Jacques

    2016-10-01

    The present study was intended to combine three therapeutic approaches in a well-defined rat model of spinal cord injury, a lateral hemisection at thoracic level. A guidance channel was implanted at the lesion site. This channel was seeded with native Schwann cells or Schwann cells that had been previously transduced with a lentiviral vector carrying the GDNF gene. Thereafter, these experiences were reproduced in animals injected with lentiviral vectors carrying a shRNA for GFAP (Lv-shGFAP), which has recently been shown to block glial scar formation. Functional evaluations showed that Lv-shGFAP induced a significant improvement in recovery in animals grafted with Schwann cells. Histological studies demonstrated the outgrowth of axons in the guidance channel containing Schwann cells transduced or not with GDNF. This axonal growth was enhanced in rats receiving Lv-shGFAP vector. Also, a significant increase of serotonergic innervation of the injured hemicord, distal to the lesion, was found only in animals treated with Lv-shGFAP vectors. Importantly, this study confirms that glial scar formation is a major impediment for axonal sprouting after spinal cord injury, and emphasizes the importance of serotonergic innervation for locomotor function. Moreover we show a significant additive effect of a combinatorial approach to axonal regeneration in the injured spinal cord.

  3. Side-To-Side Nerve Bridges Support Donor Axon Regeneration Into Chronically Denervated Nerves and Are Associated With Characteristic Changes in Schwann Cell Phenotype.

    Science.gov (United States)

    Hendry, J Michael; Alvarez-Veronesi, M Cecilia; Snyder-Warwick, Alison; Gordon, Tessa; Borschel, Gregory H

    2015-11-01

    Chronic denervation resulting from long nerve regeneration times and distances contributes greatly to suboptimal outcomes following nerve injuries. Recent studies showed that multiple nerve grafts inserted between an intact donor nerve and a denervated distal recipient nerve stump (termed "side-to-side nerve bridges") enhanced regeneration after delayed nerve repair. To examine the cellular aspects of axon growth across these bridges to explore the "protective" mechanism of donor axons on chronically denervated Schwann cells. In Sprague Dawley rats, 3 side-to-side nerve bridges were placed over a 10-mm distance between an intact donor tibial (TIB) nerve and a recipient denervated common peroneal (CP) distal nerve stump. Green fluorescent protein-expressing TIB axons grew across the bridges and were counted in cross section after 4 weeks. Immunofluorescent axons and Schwann cells were imaged over a 4-month period. Denervated Schwann cells dedifferentiated to a proliferative, nonmyelinating phenotype within the bridges and the recipient denervated CP nerve stump. As donor TIB axons grew across the 3 side-to-side nerve bridges and into the denervated CP nerve, the Schwann cells redifferentiated to the myelinating phenotype. Bridge placement led to an increased mass of hind limb anterior compartment muscles after 4 months of denervation compared with muscles whose CP nerve was not "protected" by bridges. This study describes patterns of donor axon regeneration and myelination in the denervated recipient nerve stump and supports a mechanism where these donor axons sustain a proregenerative state to prevent deterioration in the face of chronic denervation.

  4. An inflammatory gene signature distinguishes neurofibroma Schwann cells and macrophages from cells in the normal peripheral nervous system

    Science.gov (United States)

    Choi, Kwangmin; Komurov, Kakajan; Fletcher, Jonathan S.; Jousma, Edwin; Cancelas, Jose A.; Wu, Jianqiang; Ratner, Nancy

    2017-01-01

    Neurofibromas are benign peripheral nerve tumors driven by NF1 loss in Schwann cells (SCs). Macrophages are abundant in neurofibromas, and macrophage targeted interventions may have therapeutic potential in these tumors. We generated gene expression data from fluorescence-activated cell sorted (FACS) SCs and macrophages from wild-type and mutant nerve and neurofibroma to identify candidate pathways involved in SC-macrophage cross-talk. While in 1-month-old Nf1 mutant nerve neither SCs nor macrophages significantly differed from their normal counterparts, both macrophages and SCs showed significantly altered cytokine gene expression in neurofibromas. Computationally reconstructed SC-macrophage molecular networks were enriched for inflammation-associated pathways. We verified that neurofibroma SC conditioned medium contains macrophage chemo-attractants including colony stimulation factor 1 (CSF1). Network analysis confirmed previously implicated pathways and predict novel paracrine and autocrine loops involving cytokines, chemokines, and growth factors. Network analysis also predicted a central role for decreased type-I interferon signaling. We validated type-I interferon expression in neurofibroma by protein profiling, and show that treatment of neurofibroma-bearing mice with polyethylene glycolyated (PEGylated) type-I interferon-α2b reduces the expression of many cytokines overexpressed in neurofibroma. These studies reveal numerous potential targetable interactions between Nf1 mutant SCs and macrophages for further analyses. PMID:28256556

  5. Salidroside attenuates colistin-induced neurotoxicity in RSC96 Schwann cells through PI3K/Akt pathway.

    Science.gov (United States)

    Lu, Ziyin; Jiang, Guozheng; Chen, Ying; Wang, Jian; Muhammad, Ishfaq; Zhang, Ling; Wang, Rui; Liu, Fangping; Li, Rui; Qian, Feng; Li, Jichang

    2017-06-01

    Neurotoxicity is a key dose-limiting factor for colistin therapy. This study aimed to investigate the protective effect of Salidroside on colistin-induced neurotoxicity in RSC96 Schwann cells and the underlying mechanisms. After Salidroside (12.5, 25, 50 μg/mL) treatment for 2 h, the cells were cultured with 250 μg/mL colistin for 24 h. In order to investigate the role of phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt) pathway, the cells were pre-treated with LY294002 (12.5 μmol/L, a specific inhibitor of PI3K phosphorylation) for 1 h before Salidroside (50 μg/mL) treatment, then were co-cultured with colistin (250 μg/mL) for 24 h. The results showed that colistin treatment could induce apoptotic cell death which was associated with oxidative stress injury. Salidroside could reduce colistin-induced neurotoxicity, decrease the effect of colistin on the reduced expression levels of p-Akt and Bcl-2, and increased the expresion of Bax, release of Cyt c, and activation of caspase-3. However, the protective effect of Salidroside against colistin-induced apoptosis was partly abolished by LY294002. These findings suggest that Salidroside could attenuate colistin-induced neurotoxicity in RSC96 Schwann cells via the PI3K/Akt pathway. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Transfer of vesicles from Schwann cell to axon: a novel mechanism of communication in the peripheral nervous system

    Directory of Open Access Journals (Sweden)

    María Alejandra eLopez-Verrilli

    2012-06-01

    Full Text Available Schwann cells (SCs are the glial component of the peripheral nervous system, with essential roles during development and maintenance of axons, as well as during regenerative processes after nerve injury. SCs increase conduction velocities by myelinating axons, regulate synaptic activity at presynaptic nerve terminals and are a source of trophic factors to neurons. Thus, development and maintenance of peripheral nerves are crucially dependent on local signalling between SCs and axons. In addition to the classic mechanisms of intercellular signalling, the possibility of communication through secreted vesicles has been poorly explored to date. Interesting recent findings suggest the occurrence of lateral transfer mediated by vesicles from glial cells to axons that could have important roles in axonal growth and axonal regeneration. Here, we review the role of vesicular transfer from SCs to axons and propose the benefits of this means in supporting neuronal and axonal maintenance and regeneration after nerve damage.

  7. Comparative proteomic analysis of primary schwann cells and a spontaneously immortalized schwann cell line RSC 96: a comprehensive overview with a focus on cell adhesion and migration related proteins.

    Science.gov (United States)

    Ji, Yuhua; Shen, Mi; Wang, Xin; Zhang, Shuqiang; Yu, Shu; Chen, Gang; Gu, Xiaosong; Ding, Fei

    2012-06-01

    Schwann cells (SCs) are the principal glial cells of the peripheral nervous system (PNS). As a result of tissue heterogeneity and difficulties in the isolation and culture of primary SCs, a considerable understanding of SC biology is obtained from SC lines. However, the differences between the primary SCs and SC lines remain uncertain. In the present study, quantitative proteomic analysis based on isobaric tags for relative and absolute quantitation (iTRAQ) labeling was conducted to obtain an unbiased view of the proteomic profiles of primary rat SCs and RSC96, a spontaneously immortalized rat SC line. Out of 1757 identified proteins (FDR RSC96. Bioinformatics analysis indicated the unique features of spontaneous immortalization, illustrated the dedifferentiated state of RSC96, and highlighted a panel of novel proteins associated with cell adhesion and migration including CADM4, FERMT2, and MCAM. Selected proteomic data and the requirement of these novel proteins in SC adhesion and migration were properly validated. Taken together, our data collectively revealed proteome differences between primary SCs and RSC96, validated several differentially expressed proteins with potential biological significance, and generated a database that may serve as a useful resource for studies of SC biology and pathology.

  8. Subarachnoid Space Transplantation of Schwann and/or Olfactory Ensheathing Cells Following Severe Spinal Cord Injury Fails to Improve Locomotor Recovery in Rats

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    Mohsen Nategh

    2016-10-01

    Full Text Available Treatment of spinal cord injury by exogenous cells has brought both successful and unsuccessful results. Olfactory ensheathing cells and Schwann cells have been widely used for transplantation purposes. In this study, we investigated the effects of these cells on contused spinal cord by introducing cells into subarachnoid space. Fifty thousand Schwann cells or olfactory ensheathing cells or a mixture of both cell types were transplanted one week after a 3-second clip compression injury at T-9 spinal cord level in rats. Starting from the day one of spinal cord injury, animals were assessed for six months by BBB test and then were sacrificed for immunohistochemistry labeling of the spinal cord injury site. There was no locomotor recovery in any of the treatment groups including controls. Immunohistochemistry assessment indicated positive labeling of P75 and S100 markers in the cell-transplanted groups compared with control. Our data suggest that transplantation of Schwann cells and/or olfactory ensheathing cells into the subarachnoid space does not improve motor recovery in severely injured spinal cord, at least with the number of cells transplanted here. This, however, should not be regarded as an essentially negative outcome, and further studies which consider higher densities of cells are required.

  9. Methylcobalamin promotes the differentiation of Schwann cells and remyelination in lysophosphatidylcholine-induced demyelination of the rat sciatic nerve

    Directory of Open Access Journals (Sweden)

    Shunsuke eNishimoto

    2015-08-01

    Full Text Available Schwann cells (SCs are constituents of the peripheral nervous system. The differentiation of SCs in injured peripheral nerves is critical for regeneration after injury. Methylcobalamin (MeCbl is a vitamin B12 analog that is necessary for the maintenance of the peripheral nervous system. In this study, we estimated the effect of MeCbl on SCs. We showed that MeCbl downregulated the activity of Erk1/2 and promoted the expression of the myelin basic protein in SCs. In a dorsal root ganglion neuron–SC coculture system, myelination was promoted by MeCbl. In a focal demyelination rat model, MeCbl promoted remyelination and motor and sensory functional regeneration. MeCbl promoted the in vitro differentiation of SCs and in vivo myelination in a rat demyelination model and may be a novel therapy for several types of nervous disorders.

  10. Schwann Cells Overexpressing FGF-2 Alone or Combined with Manual Stimulation Do Not Promote Functional Recovery after Facial Nerve Injury

    Directory of Open Access Journals (Sweden)

    Kirsten Haastert

    2009-01-01

    Full Text Available Purpose. To determine whether transplantation of Schwann cells (SCs overexpressing different isoforms of fibroblast growth factor 2 (FGF-2 combined with manual stimulation (MS of vibrissal muscles improves recovery after facial nerve transection in adult rat. Procedures. Transected facial nerves were entubulated with collagen alone or collagen plus naïve SCs or transfected SCs. Half of the rats received daily MS. Collateral branching was quantified from motoneuron counts after retrograde labeling from 3 facial nerve branches. Quality assessment of endplate reinnervation was combined with video-based vibrissal function analysis. Results. There was no difference in the extent of collateral axonal branching. The proportion of polyinnervated motor endplates for either naïve SCs or FGF-2 over-expressing SCs was identical. Postoperative MS also failed to improve recovery. Conclusions. Neither FGF-2 isoform changed the extent of collateral branching or polyinnervation of motor endplates; furthermore, this motoneuron response could not be overridden by MS.

  11. 大鼠耳蜗雪旺细胞的体外培养和纯化%Purification and Separation of Cochlear Schwann Cells by Immunomagnetic Beads Method

    Institute of Scientific and Technical Information of China (English)

    张心怡; 何亚; 王娟; 米文娟; 邱建华

    2012-01-01

    目的:探讨利用免疫磁珠从新生SD大鼠耳蜗螺旋神经节分离培养获得大量、高纯度雪旺细胞的方法.方法:选用1-3d SD大鼠,无菌条件下暴露双侧听泡,在高倍镜下仔细剥离蜗壳,开放耳蜗,完整取出耳蜗组织,分离并且除去膜蜗管外侧壁的血管纹和基底膜组织,然后剪碎.用0.25%的胰蛋白酶消化,用胎牛血清中止消化,离心以后加入DMEM/F12培养液培养.3-5天后对细胞应用免疫磁珠阳性分选方法进行纯化,培养2天后进行传代接种,培养过程中对提纯后的大鼠耳蜗雪旺细胞进行形态学观察、并绘制其生长曲线,采用细胞免疫荧光染色对细胞进行S-100免疫荧光鉴定并且计算细胞纯度.结果:分离培养后所得的细胞即为雪旺细胞;利用免疫磁珠阳性分选法对培养所得的细胞进行纯化,纯化后的大鼠耳蜗雪旺细胞纯度为97%±1.2%.结论:免疫磁殊法是一种有效的分离纯化新生大鼠仔鼠耳蜗螺旋神经节雪旺细胞的方法.所得耳蜗雪旺细胞活力强、纯度高,可以用于耳蜗雪旺细胞与螺旋神经节轴突的生长和再生等相关研究.%Objective: To introduce a method to obtain Schwann cells from newly born SD rats massively and purely by immuno-magnetic beads method. Method: SD rats, which were born l-3days, were chosen. Under sterile conditions, expose the bilateral auditory vesicles, dissect the snail shell at high magnification, open cochlea and take out the cochlea completely, isolate and remove stria vascu-laris and basement membrane on the lateral wall of membranous cochlear duct, and cut in pieces. 0.25% trypsin and 0.2% collagenase I was used for digestion, FBS was used to suspend the digestion, and that was centrifuged with the addition of DF12 medium. After 3-5days, cells were purified using immunomagnetic microbeads, and cell passage was done after culturing for two days. During the whole process, the change of Schwann cells was

  12. In vitro biocompatibility of schwann cells on surfaces of biocompatible polymeric electrospun fibrous and solution-cast film scaffolds.

    Science.gov (United States)

    Sangsanoh, Pakakrong; Waleetorncheepsawat, Suchada; Suwantong, Orawan; Wutticharoenmongkol, Patcharaporn; Weeranantanapan, Oratai; Chuenjitbuntaworn, Boontharika; Cheepsunthorn, Poonlarp; Pavasant, Prasit; Supaphol, Pitt

    2007-05-01

    The in vitro responses of Schwann cells (RT4-D6P2T, a schwannoma cell line derived from a chemically induced rat peripheral neurotumor) on various types of electrospun fibrous scaffolds of some commercially available biocompatible and biodegradable polymers, i.e., poly(3-hydroxybutyrate) (PHB), poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), polycaprolactone (PCL), poly(l-lactic acid) (PLLA), and chitosan (CS), were reported in comparison with those of the cells on corresponding solution-cast film scaffolds as well as on a tissue-culture polystyrene plate (TCPS), used as the positive control. At 24 h after cell seeding, the viability of the attached cells on the various substrates could be ranked as follows: PCL film > TCPS > PCL fibrous > PLLA fibrous > PHBV film > CS fibrous approximately CS film approximately PLLA film > PHB film > PHBV fibrous > PHB fibrous. At day 3 of cell culture, the viability of the proliferated cells on the various substrates could be ranked as follows: TCPS > PHBV film > PLLA film > PCL film > PLLA fibrous > PHB film approximately PCL fibrous > CS fibrous > CS film > PHB fibrous > PHBV fibrous. At approximately 8 h after cell seeding, the cells on the flat surfaces of all of the film scaffolds and that of the PCL nanofibrous scaffold appeared in their characteristic spindle shape, while those on the surfaces of the PHB, PHBV, and PLLA macrofibrous scaffolds also appeared in their characteristic spindle shape, but with the cells being able to penetrate to the inner side of the scaffolds.

  13. Extensive cell migration, axon regeneration, and improved function with polysialic acid-modified Schwann cells after spinal cord injury.

    Science.gov (United States)

    Ghosh, Mousumi; Tuesta, Luis M; Puentes, Rocio; Patel, Samik; Melendez, Kiara; El Maarouf, Abderrahman; Rutishauser, Urs; Pearse, Damien Daniel

    2012-05-01

    Schwann cell (SC) implantation after spinal cord injury (SCI) promotes axonal regeneration, remyelination repair, and functional recovery. Reparative efficacy, however, may be limited because of the inability of SCs to migrate outward from the lesion-implant site. Altering SC cell surface properties by overexpressing polysialic acid (PSA) has been shown to promote SC migration. In this study, a SCI contusion model was used to evaluate the migration, supraspinal axon growth support, and functional recovery associated with polysialyltransferase (PST)-overexpressing SCs [PST-green fluorescent protein (GFP) SCs] or controls (GFP SCs). Compared with GFP SCs, which remained confined to the injection site at the injury center, PST-GFP SCs migrated across the lesion:host cord interface for distances of up to 4.4 mm within adjacent host tissue. In addition, with PST-GFP SCs, there was extensive serotonergic and corticospinal axon in-growth within the implants that was limited in the GFP SC controls. The enhanced migration of PST-GFP SCs was accompanied by significant growth of these axons caudal to lesion. Animals receiving PST-GFP SCs exhibited improved functional outcome, both in the open-field and on the gridwalk test, beyond the modest improvements provided by GFP SC controls. This study for the first time demonstrates that a lack of migration by SCs may hinder their reparative benefits and that cell surface overexpression of PSA enhances the ability of implanted SCs to associate with and support the growth of corticospinal axons. These results provide further promise that PSA-modified SCs will be a potent reparative approach for SCI. © 2012 Wiley Periodicals, Inc.

  14. Proteomics and transcriptomics of peripheral nerve tissue and cells unravel new aspects of the human Schwann cell repair phenotype.

    Science.gov (United States)

    Weiss, Tamara; Taschner-Mandl, Sabine; Bileck, Andrea; Slany, Astrid; Kromp, Florian; Rifatbegovic, Fikret; Frech, Christian; Windhager, Reinhard; Kitzinger, Hugo; Tzou, Chieh-Han; Ambros, Peter F; Gerner, Christopher; Ambros, Inge M

    2016-12-01

    The remarkable feature of Schwann cells (SCs) to transform into a repair phenotype turned the spotlight on this powerful cell type. SCs provide the regenerative environment for axonal re-growth after peripheral nerve injury (PNI) and play a vital role in differentiation of neuroblastic tumors into a benign subtype of neuroblastoma, a tumor originating from neural crest-derived neuroblasts. Hence, understanding their mode-of-action is of utmost interest for new approaches in regenerative medicine, but also for neuroblastoma therapy. However, literature on human SCs is scarce and it is unknown to which extent human SC cultures reflect the SC repair phenotype developing after PNI in patients. We performed high-resolution proteome profiling and RNA-sequencing on highly enriched human SC and fibroblast cultures, control and ex vivo degenerated nerve explants to identify novel molecules and functional processes active in repair SCs. In fact, we found cultured SCs and degenerated nerves to share a similar repair SC-associated expression signature, including the upregulation of JUN, as well as two prominent functions, i.e., myelin debris clearance and antigen presentation via MHCII. In addition to myelin degradation, cultured SCs were capable of actively taking up cell-extrinsic components in functional phagocytosis and co-cultivation assays. Moreover, in cultured SCs and degenerated nerve tissue MHCII was upregulated at the cellular level along with high expression of chemoattractants and co-inhibitory rather than -stimulatory molecules. These results demonstrate human SC cultures to execute an inherent program of nerve repair and support two novel repair SC functions, debris clearance via phagocytosis-related mechanisms and type II immune-regulation. GLIA 2016;64:2133-2153. © 2016 The Authors. Glia Published by Wiley Periodicals, Inc.

  15. Improvement of Parkinsonian behavior with co-grafts of Schwann cells and neural stem cells in the rat

    Institute of Scientific and Technical Information of China (English)

    Ying Xia; Chengchuan Jiang; Zhongliang Ding; Yang Wang; Bin Xu; Linyin Feng

    2008-01-01

    BACKGROUND: Due to the lack of autograft transplant rejection, Schwann cells (SCs) can promote the proliferation of embryonic stem cells and the induction of dopaminergic neurons. Mesencephalic stem cells can be induced to produce dopaminergic neurons. The therapeutic effects of co-grafts of SCs and neural stem cells (NSCs) deserves further study and verification in Parkinsonian animal models.OBJECTIVE: To investigate the effects of Schwann cells and mesencephalic NSC co-grafts in Parkinsonian animal models on animal behavior and histology.DESIGN: Randomized controlled experiment.SETTING: Fudan University; Institute of Neuroscience, Chinese Academy of Sciences.MATERIALS: The following animals were obtained from the Experimental Animal Center, Shanghai Institute for Biological Science, Chinese Academy of Sciences: 5 Sprague-Dawley rats, embryonic day (E) 13–16; 16 neonatal Sprague-Dawley rats, postnatal day 1–3; and 18 adult SD rats of both genders. Animal experimentation met animal ethical approval.METHODS: The experiment was performed at the Department of Anatomy, Histology and Embryology, Shanghai Medical Center, Fudan University from September 2005 to January 2007. The mesencephalic NSCs were obtained from the brains of SD rats at E 13–16, and SCs were harvested from the sciatic nerves of neonatal rats at day 1–3. Hemiparkinsonian rats (n =18) were selected for transplantation after estimating rotational behavior in response to apomorphine and were randomly assigned to three groups: control group, NSC group, and co-graft group. There were 6 rats in each group. Either phosphate buffered saline (PBS), NSCs, or SCs plus NSCs were transplanted into the right neostriatum of Parkinsonian rats, respectively.MAIN OUTCOME MEASURES: ① Rotational behavior was induced by apomorphine (0.05 mg/kg, I.p.) 2, 4, 6, 8, and 10 weeks after transplantation, and the number of rotations were counted. ② Differentiation and survival of dopaminergic neurons in the right

  16. A rapid and versatile method for the isolation, purification and cryogenic storage of Schwann cells from adult rodent nerves.

    Science.gov (United States)

    Andersen, Natalia D; Srinivas, Shruthi; Piñero, Gonzalo; Monje, Paula V

    2016-08-23

    We herein developed a protocol for the rapid procurement of adult nerve-derived Schwann cells (SCs) that was optimized to implement an immediate enzymatic dissociation of fresh nerve tissue while maintaining high cell viability, improving yields and minimizing fibroblast and myelin contamination. This protocol introduces: (1) an efficient method for enzymatic cell release immediately after removal of the epineurium and extensive teasing of the nerve fibers; (2) an adaptable drop-plating method for selective cell attachment, removal of myelin debris, and expansion of the initial SC population in chemically defined medium; (3) a magnetic-activated cell sorting purification protocol for rapid and effective fibroblast elimination; and (4) an optional step of cryopreservation for the storage of the excess of cells. Highly proliferative SC cultures devoid of myelin and fibroblast growth were obtained within three days of nerve processing. Characterization of the initial, expanded, and cryopreserved cell products confirmed maintenance of SC identity, viability and growth rates throughout the process. Most importantly, SCs retained their sensitivity to mitogens and potential for differentiation even after cryopreservation. To conclude, this easy-to-implement and clinically relevant protocol allows for the preparation of expandable homogeneous SC cultures while minimizing time, manipulation of the cells, and exposure to culture variables.

  17. The Effect of Electrospun Gelatin Fibers Alignment on Schwann Cell and Axon Behavior and Organization in the Perspective of Artificial Nerve Design.

    Science.gov (United States)

    Gnavi, Sara; Fornasari, Benedetta Elena; Tonda-Turo, Chiara; Laurano, Rossella; Zanetti, Marco; Ciardelli, Gianluca; Geuna, Stefano

    2015-01-01

    Electrospun fibrous substrates mimicking extracellular matrices can be prepared by electrospinning, yielding aligned fibrous matrices as internal fillers to manufacture artificial nerves. Gelatin aligned nano-fibers were prepared by electrospinning after tuning the collector rotation speed. The effect of alignment on cell adhesion and proliferation was tested in vitro using primary cultures, the Schwann cell line, RT4-D6P2T, and the sensory neuron-like cell line, 50B11. Cell adhesion and proliferation were assessed by quantifying at several time-points. Aligned nano-fibers reduced adhesion and proliferation rate compared with random fibers. Schwann cell morphology and organization were investigated by immunostaining of the cytoskeleton. Cells were elongated with their longitudinal body parallel to the aligned fibers. B5011 neuron-like cells were aligned and had parallel axon growth when cultured on the aligned gelatin fibers. The data show that the alignment of electrospun gelatin fibers can modulate Schwann cells and axon organization in vitro, suggesting that this substrate shows promise as an internal filler for the design of artificial nerves for peripheral nerve reconstruction.

  18. GDNF reverses the inhibitory properties of reactive astrocytes allowing robust axonal regeneration through Schwann cell-seeded guidance channels after spinal cord injury

    OpenAIRE

    Deng, Ling-Xiao; Hu, Jianguo; Liu, Naikui; Wang, Xiaofei; Smith, George M.; Wen, Xuejun; Xu, Xiao-Ming

    2011-01-01

    Reactive astrogliosis has been considered as a major impediment for axonal regeneration after injuries in the mammalian central nervous system (CNS). Here we report that glial cell line-derived neurotrophic factor (GDNF), combined with transplanted Schwann cells (SCs), effectively reversed the inhibitory properties of astrocytes at graft-host interfaces allowing robust axonal regeneration, concomitant with vigorous migration of host astrocytes, into SC-seeded semi-permeable guidance channels ...

  19. Characterization and Schwann Cell Seeding of up to 15.0 cm Long Spider Silk Nerve Conduits for Reconstruction of Peripheral Nerve Defects

    Directory of Open Access Journals (Sweden)

    Tim Kornfeld

    2016-11-01

    Full Text Available Nerve reconstruction of extended nerve defect injuries still remains challenging with respect to therapeutic options. The gold standard in nerve surgery is the autologous nerve graft. Due to the limitation of adequate donor nerves, surgical alternatives are needed. Nerve grafts made out of either natural or artificial materials represent this alternative. Several biomaterials are being explored and preclinical and clinical applications are ongoing. Unfortunately, nerve conduits with successful enhancement of axonal regeneration for nerve defects measuring over 4.0 cm are sparse and no conduits are available for nerve defects extending to 10.0 cm. In this study, spider silk nerve conduits seeded with Schwann cells were investigated for in vitro regeneration on defects measuring 4.0 cm, 10.0 cm and 15.0 cm in length. Schwann cells (SCs were isolated, cultured and purified. Cell purity was determined by immunofluorescence. Nerve grafts were constructed out of spider silk from Nephila edulis and decellularized ovine vessels. Finally, spider silk implants were seeded with purified Schwann cells. Cell attachment was observed within the first hour. After 7 and 21 days of culture, immunofluorescence for viability and determination of Schwann cell proliferation and migration throughout the conduits was performed. Analyses revealed that SCs maintained viable (>95% throughout the conduits independent of construct length. SC proliferation on the spider silk was determined from day 7 to day 21 with a proliferation index of 49.42% arithmetically averaged over all conduits. This indicates that spider silk nerve conduits represent a favorable environment for SC attachment, proliferation and distribution over a distance of least 15.0 cm in vitro. Thus spider silk nerve implants are a highly adequate biomaterial for nerve reconstruction.

  20. Characterization and Schwann Cell Seeding of up to 15.0 cm Long Spider Silk Nerve Conduits for Reconstruction of Peripheral Nerve Defects.

    Science.gov (United States)

    Kornfeld, Tim; Vogt, Peter M; Bucan, Vesna; Peck, Claas-Tido; Reimers, Kerstin; Radtke, Christine

    2016-11-30

    Nerve reconstruction of extended nerve defect injuries still remains challenging with respect to therapeutic options. The gold standard in nerve surgery is the autologous nerve graft. Due to the limitation of adequate donor nerves, surgical alternatives are needed. Nerve grafts made out of either natural or artificial materials represent this alternative. Several biomaterials are being explored and preclinical and clinical applications are ongoing. Unfortunately, nerve conduits with successful enhancement of axonal regeneration for nerve defects measuring over 4.0 cm are sparse and no conduits are available for nerve defects extending to 10.0 cm. In this study, spider silk nerve conduits seeded with Schwann cells were investigated for in vitro regeneration on defects measuring 4.0 cm, 10.0 cm and 15.0 cm in length. Schwann cells (SCs) were isolated, cultured and purified. Cell purity was determined by immunofluorescence. Nerve grafts were constructed out of spider silk from Nephila edulis and decellularized ovine vessels. Finally, spider silk implants were seeded with purified Schwann cells. Cell attachment was observed within the first hour. After 7 and 21 days of culture, immunofluorescence for viability and determination of Schwann cell proliferation and migration throughout the conduits was performed. Analyses revealed that SCs maintained viable (>95%) throughout the conduits independent of construct length. SC proliferation on the spider silk was determined from day 7 to day 21 with a proliferation index of 49.42% arithmetically averaged over all conduits. This indicates that spider silk nerve conduits represent a favorable environment for SC attachment, proliferation and distribution over a distance of least 15.0 cm in vitro. Thus spider silk nerve implants are a highly adequate biomaterial for nerve reconstruction.

  1. Manipulation of Schwann cell migration across the astrocyte boundary by polysialyltransferase-loaded superparamagnetic nanoparticles under magnetic field

    Directory of Open Access Journals (Sweden)

    Xia B

    2016-12-01

    Full Text Available Bing Xia,* Liangliang Huang,* Lei Zhu, Zhongyang Liu, Teng Ma, Shu Zhu, Jinghui Huang, Zhuojing Luo Department of Orthopaedics, Xijing Hospital, Fourth Military Medical University, Xi’an, Shaanxi, People’s Republic of China *These authors contributed equally to this work Abstract: Schwann cell (SC transplantation is an attractive strategy for spinal cord injury (SCI. However, the efficacy of SC transplantation has been limited by the poor migratory ability of SCs in the astrocyte-rich central nervous system (CNS environment and the inability to intermingle with the host astrocyte. In this study, we first magnetofected SCs by polysialyltransferase-functionalized superparamagnetic iron oxide nanoparticles (PST/SPIONs to induce overexpression of polysialylation of neural cell adhesion molecule (PSA-NCAM to enhance SC migration ability, before manipulating the direction of SC migration with the assistance of an applied magnetic field (MF. It was found that magnetofection with PST/SPIONs significantly upregulated the expression of PSA-NCAM in SCs, which significantly enhanced the migration ability of SCs, but without preferential direction in the absence of MF. The number and averaged maximum distance of SCs with PST/SPIONs migrating into the astrocyte domain were significantly enhanced by an applied MF. In a 300 µm row along the astrocyte boundary, the number of SCs with PST/SPIONs migrating into the astrocyte domain under an MF was 2.95 and 6.71 times higher than that in the absence of MF and the intact control SCs, respectively. More interestingly, a confrontation assay demonstrated that SCs with PST/SPIONs were in close contact with astrocytes and no longer formed boundaries in the presence of MF. In conclusion, SCs with PST/SPIONs showed enhanced preferential migration along the axis of a magnetic force, which might be beneficial for the formation of Büngner bands in the CNS. These findings raise the possibilities of enhancing the

  2. Hyperglycemia alters the schwann cell mitochondrial proteome and decreases coupled respiration in the absence of superoxide production.

    Science.gov (United States)

    Zhang, Liang; Yu, Cuijuan; Vasquez, Francisco E; Galeva, Nadya; Onyango, Isaac; Swerdlow, Russell H; Dobrowsky, Rick T

    2010-01-01

    Hyperglycemia-induced mitochondrial dysfunction contributes to sensory neuron pathology in diabetic neuropathy. Although Schwann cells (SCs) also undergo substantial degeneration in diabetic neuropathy, the effect of hyperglycemia on the SC mitochondrial proteome and mitochondrial function has not been examined. Stable isotope labeling with amino acids in cell culture (SILAC) was used to quantify the temporal effect of hyperglycemia on the mitochondrial proteome of primary SCs isolated from neonatal rats. Of 317 mitochondrial proteins identified, about 78% were quantified and detected at multiple time points. Pathway analysis indicated that proteins associated with mitochondrial dysfunction, oxidative phosphorylation, the TCA cycle, and detoxification were significantly increased in expression and over-represented. Assessing mitochondrial respiration in intact SCs indicated that hyperglycemia increased the overall rate of oxygen consumption but decreased the efficiency of coupled respiration. Although a glucose-dependent increase in superoxide production occurs in embryonic sensory neurons, hyperglycemia did not induce a substantial change in superoxide levels in SCs. This correlated with a 1.9-fold increase in Mn superoxide dismutase expression, which was confirmed by immunoblot and enzymatic activity assays. These data support that hyperglycemia alters mitochondrial respiration and can cause remodeling of the SC mitochondrial proteome independent of significant contributions from glucose-induced superoxide production.

  3. Electroactive biodegradable polyurethane significantly enhanced Schwann cells myelin gene expression and neurotrophin secretion for peripheral nerve tissue engineering.

    Science.gov (United States)

    Wu, Yaobin; Wang, Ling; Guo, Baolin; Shao, Yongpin; Ma, Peter X

    2016-05-01

    Myelination of Schwann cells (SCs) is critical for the success of peripheral nerve regeneration, and biomaterials that can promote SCs' neurotrophin secretion as scaffolds are beneficial for nerve repair. Here we present a biomaterials-approach, specifically, a highly tunable conductive biodegradable flexible polyurethane by polycondensation of poly(glycerol sebacate) and aniline pentamer, to significantly enhance SCs' myelin gene expression and neurotrophin secretion for peripheral nerve tissue engineering. SCs are cultured on these conductive polymer films, and the biocompatibility of these films and their ability to enhance myelin gene expressions and sustained neurotrophin secretion are successfully demonstrated. The mechanism of SCs' neurotrophin secretion on conductive films is demonstrated by investigating the relationship between intracellular Ca(2+) level and SCs' myelination. Furthermore, the neurite growth and elongation of PC12 cells are induced by adding the neurotrophin medium suspension produced from SCs-laden conductive films. These data suggest that these conductive degradable polyurethanes that enhance SCs' myelin gene expressions and sustained neurotrophin secretion perform great potential for nerve regeneration applications.

  4. Mild hypothermia combined with a scaffold of NgR-silenced neural stem cells/Schwann cells to treat spinal cord injur y

    Institute of Scientific and Technical Information of China (English)

    Dong Wang; Jinhua Liang; Jianjun Zhang; Shuhong Liu; Wenwen Sun

    2014-01-01

    Because the inhibition of Nogo proteins can promote neurite growth and nerve cell differenti-ation, a cell-scaffold complex seeded with Nogo receptor (NgR)-silenced neural stem cells and Schwann cells may be able to improve the microenvironment for spinal cord injury repair. Previ-ous studies have found that mild hypothermia helps to attenuate secondary damage in the spinal cord and exerts a neuroprotective effect. Here, we constructed a cell-scaffold complex consisting of a poly(D,L-lactide-co-glycolic acid) (PLGA) scaffold seeded with NgR-silenced neural stem cells and Schwann cells, and determined the effects of mild hypothermia combined with the cell-scaffold complexes on the spinal cord hemi-transection injury in the T9 segment in rats. Compared with the PLGA group and the NgR-silencing cells+PLGA group, hindlimb motor function and nerve electrophysiological function were clearly improved, pathological changes in the injured spinal cord were attenuated, and the number of surviving cells and nerve ifbers were increased in the group treated with the NgR-silenced cell scaffold+mild hypothermia at 34°C for 6 hours. Furthermore, fewer pathological changes to the injured spinal cord and more surviv-ing cells and nerve ifbers were found after mild hypothermia therapy than in injuries not treated with mild hypothermia. These experimental results indicate that mild hypothermia combined with NgR gene-silenced cells in a PLGA scaffold may be an effective therapy for treating spinal cord injury.

  5. The use of fiber-reinforced scaffolds cocultured with Schwann cells and vascular endothelial cells to repair rabbit sciatic nerve defect with vascularization.

    Science.gov (United States)

    Gao, Hongyang; You, Yang; Zhang, Guoping; Zhao, Feng; Sha, Ziyi; Shen, Yong

    2013-01-01

    To explore the feasibility of biodegradable fiber-reinforced 3D scaffolds with satisfactory mechanical properties for the repair of long-distance sciatic nerve defect in rabbits and effects of vascularized graft in early stage on the recovery of neurological function, Schwann cells and vascular endothelial cells were cocultured in the fiber-reinforced 3D scaffolds. Experiment group which used prevascularized nerve complex for the repair of sciatic nerve defect and control group which only cultured with Schwann cells were set. The animals in both groups underwent electromyography to show the status of the neurological function recovery at 4, 8, and 16 weeks after the surgery. Sciatic nerve regeneration and myelination were observed under the light microscope and electron microscope. Myelin sheath thickness, axonal diameter, and number of myelinated nerve fiber were quantitatively analyzed using image analysis system. The recovery of foot ulcer, the velocity of nerve conduction, the number of regenerating nerve fiber, and the recovery of ultrastructure were increased in the experimental group than those in the control group. Prevascularized tissue engineered fiber-reinforced 3D scaffolds for the repair of sciatic nerve defects in rabbits can effectively promote the recovery of neurological function.

  6. The Use of Fiber-Reinforced Scaffolds Cocultured with Schwann Cells and Vascular Endothelial Cells to Repair Rabbit Sciatic Nerve Defect with Vascularization

    Directory of Open Access Journals (Sweden)

    Hongyang Gao

    2013-01-01

    Full Text Available To explore the feasibility of biodegradable fiber-reinforced 3D scaffolds with satisfactory mechanical properties for the repair of long-distance sciatic nerve defect in rabbits and effects of vascularized graft in early stage on the recovery of neurological function, Schwann cells and vascular endothelial cells were cocultured in the fiber-reinforced 3D scaffolds. Experiment group which used prevascularized nerve complex for the repair of sciatic nerve defect and control group which only cultured with Schwann cells were set. The animals in both groups underwent electromyography to show the status of the neurological function recovery at 4, 8, and 16 weeks after the surgery. Sciatic nerve regeneration and myelination were observed under the light microscope and electron microscope. Myelin sheath thickness, axonal diameter, and number of myelinated nerve fiber were quantitatively analyzed using image analysis system. The recovery of foot ulcer, the velocity of nerve conduction, the number of regenerating nerve fiber, and the recovery of ultrastructure were increased in the experimental group than those in the control group. Prevascularized tissue engineered fiber-reinforced 3D scaffolds for the repair of sciatic nerve defects in rabbits can effectively promote the recovery of neurological function.

  7. 红细胞生成素对体外培养许旺细胞的作用%Effects of erythropoietin on Schwann cells in vitro

    Institute of Scientific and Technical Information of China (English)

    吴学建; 杜盛阳

    2009-01-01

    Objective To observe the effects of EPO on GDNF secretion and cell cycle of Schwann cells(SCs) in vitro,and explore how EPO improve peripheral nerve regeneration. Methods Devided the purified Schwann cells of primary culture into three groups:group A with DMEM culture solution contained 10%fetal bovine serum and without EPO,group B with DMEM culture solution as above and 10 U/ml EPO,group C with DMEM culture solution as above and 50 U/ml EPO.The GDNF level of each group was detected in the culture by ELISA,and carried out the flow cytometry of Schwann cells on each group.Results GDNF in culture solution of group B,group C was more than that of group A,and the S-stage rate(S%)and (S+G_2M)%of Schwann cells in group B and group C more than that of group A. Conclusion EPO can increase the GDNF secretion and enhance proliferation activity of Schwann cells,which can explain how EPO improve peripheral nerve regeneration.%目的 观察促红细胞生成(erythropoietin,EPO)对体外培养许旺细胞分泌胶质细胞源性神经营养因子(GDNF)和细胞周期的影响,探讨EPO促进外周神经再生的可能机制. 方法 将原代培养、纯化的许旺细胞随机分成三组:A组(10%胎牛血清DMEM液)、B组(10%胎牛血清DMEM液加10U/ml EPO),C组(10%胎牛血清DMEM液加50 U/ml EPO),应用ELISA测定培养上清液中的GDNF水平,流式细胞术检测细胞周期分布. 结果 与A组相比,B组和C组培养上清液中的GDNF明显增高,许旺细胞处于S期百分比(S%)和(S+G_2M)%都有明显升高. 结论 EPO可增加体外培养许旺细胞分泌GDNF,并且能提高许旺细胞的增殖活性,这可能是其促进外周神经再生的重要机制之一.

  8. Effect of platelet-rich plasma (PRP) concentration on proliferation, neurotrophic function and migration of Schwann cells in vitro.

    Science.gov (United States)

    Zheng, Canbin; Zhu, Qingtang; Liu, Xiaolin; Huang, Xijun; He, Caifeng; Jiang, Li; Quan, Daping; Zhou, Xiang; Zhu, Zhaowei

    2016-05-01

    Platelet-rich plasma (PRP) contains various growth factors and appears to have the potential to promote peripheral nerve regeneration, but evidence is lacking regarding its biological effect on Schwann cells (SCs). The present study was designed to investigate the effect of PRP concentration on SCs in order to determine the plausibility of using this plasma-derived therapy for peripheral nerve injury. PRP was obtained from rats by double-step centrifugation and was characterized by determining platelet numbers and growth factor concentrations. Primary cultures of rat SCs were exposed to various concentrations of PRP (40%, 20%, 10%, 5% and 2.5%). Cell proliferation assays and flow cytometry were performed to study to assess SC proliferation. Quantitative real-time PCR and ELISA analysis were performed to determine the ability of PRP to induce SCs to produce nerve growth factor (NGF) and glial cell line-derived neurotrophic factor (GDNF). Microchemotaxis assay was used to analyse the cell migration capacity. The results obtained indicated that the platelet concentration and growth factors in our PRP preparations were significantly higher than in whole blood. Cell culture experiments showed that 2.5-20% PRP significantly stimulated SC proliferation and migration compared to untreated controls in a dose-dependent manner. In addition, the expression and secretion of NGF and GDNF were significantly increased. However, the above effects of SCs were suppressed by high PRP concentrations (40%). In conclusion, the appropriate concentration of PRP had the potency to stimulate cell proliferation, induced the synthesis of neurotrophic factors and significantly increased migration of SCs dose-dependently. Copyright © 2013 John Wiley & Sons, Ltd.

  9. The protective effect of alpha lipoic acid on Schwann cells exposed to constant or intermittent high glucose.

    Science.gov (United States)

    Sun, Lian-Qing; Chen, Ying-Ying; Wang, Xuan; Li, Xiao-Jin; Xue, Bing; Qu, Ling; Zhang, Ting-Ting; Mu, Yi-Ming; Lu, Ju-Ming

    2012-10-01

    Diabetic peripheral neuropathy (DPN) is one of the most common and costly microvascular complications of diabetes, and no effective therapy exists. Previous studies have demonstrated that oxidative stress may be the unifying factor for the damaging effect of hyperglycemia. The aim of this study was to examine the impact of treatment with Alpha lipoic acid (ALA) on the intermittent high glucose (IHG) or high glucose (HG)-induced oxidative stress-induced mitochondrial pathway activation and Schwann cells (SCs) apoptosis in vitro. Our results suggested that IHG and HG induced SCs apoptosis in both caspase-dependent and caspase-independent pathways related to oxidative stress. More importantly, the cytotoxic effect of IHG was significantly more potent than that of HG. Treatment with ALA inhibited the IHG and HG-induced oxidative stress and apoptosis in SCs. Furthermore, treatment with ALA down-regulated the Bax expression and the release of cytochrome c and AIF translocation, but up-regulated the Bcl-2 expression in SCs. Treatment with ALA attenuated the activation of caspase-3 and caspase-9 and minimized the cleavage of PARP in SCs. These findings suggest that variability in glycemic control could be more deleterious than a constant HG and ALA antagonized the IHG-induced oxidative stress, activation of mitochondrial pathway and apoptosis in SCs.

  10. Salidroside promotes peripheral nerve regeneration based on tissue engineering strategy using Schwann cells and PLGA: in vitro and in vivo

    Science.gov (United States)

    Liu, Hui; Lv, Peizhen; Zhu, Yongjia; Wu, Huayu; Zhang, Kun; Xu, Fuben; Zheng, Li; Zhao, Jinmin

    2017-01-01

    Salidriside (SDS), a phenylpropanoid glycoside derived from Rhodiola rosea L, has been shown to be neuroprotective in many studies, which may be promising in nerve recovery. In this study, the neuroprotective effects of SDS on engineered nerve constructed by Schwann cells (SCs) and Poly (lactic-co-glycolic acid) (PLGA) were studied in vitro. We further investigated the effect of combinational therapy of SDS and PLGA/SCs based tissue engineering on peripheral nerve regeneration based on the rat model of nerve injury by sciatic transection. The results showed that SDS dramatically enhanced the proliferation and function of SCs. The underlying mechanism may be that SDS affects SCs growth through the modulation of neurotrophic factors (BDNF, GDNF and CNTF). 12 weeks after implantation with a 12 mm gap of sciatic nerve injury, SDS-PLGA/SCs achieved satisfying outcomes of nerve regeneration, as evidenced by morphological and functional improvements upon therapy by SDS, PLGA/SCs or direct suture group assessed by sciatic function index, nerve conduction assay, HE staining and immunohistochemical analysis. Our results demonstrated the significant role of introducing SDS into neural tissue engineering to promote nerve regeneration.

  11. Neuregulin1 displayed on motor axons regulates terminal Schwann cell-mediated synapse elimination at developing neuromuscular junctions.

    Science.gov (United States)

    Lee, Young Il; Li, Yue; Mikesh, Michelle; Smith, Ian; Nave, Klaus-Armin; Schwab, Markus H; Thompson, Wesley J

    2016-01-26

    Synaptic connections in the nervous system are rearranged during development and in adulthood as a feature of growth, plasticity, aging, and disease. Glia are implicated as active participants in these changes. Here we investigated a signal that controls the participation of peripheral glia, the terminal Schwann cells (SCs), at the neuromuscular junction (NMJ) in mice. Transgenic manipulation of the levels of membrane-tethered neuregulin1 (NRG1-III), a potent activator of SCs normally presented on motor axons, alters the rate of loss of motor inputs at NMJs during developmental synapse elimination. In addition, NMJs of adult transgenic mice that expressed excess axonal NRG1-III exhibited continued remodeling, in contrast to the more stable morphologies of controls. In fact, synaptic SCs of these adult mice with NRG1-III overexpression exhibited behaviors evident in wild type neonates during synapse elimination, including an affinity for the postsynaptic myofiber surface and phagocytosis of nerve terminals. Given that levels of NRG1-III expression normally peak during the period of synapse elimination, our findings identify axon-tethered NRG1 as a molecular determinant for SC-driven neuromuscular synaptic plasticity.

  12. Cdc42 Promotes Schwann Cell Proliferation and Migration Through Wnt/β-Catenin and p38 MAPK Signaling Pathway After Sciatic Nerve Injury.

    Science.gov (United States)

    Han, Bin; Zhao, Jun-Ying; Wang, Wu-Tao; Li, Zheng-Wei; He, Ai-Ping; Song, Xiao-Yang

    2017-01-17

    Schwann cells (SCs) are unique glial cells in the peripheral nerve and may secrete multiple neurotrophic factors, adhesion molecules, extracellular matrix molecules to form the microenvironment of peripheral nerve regeneration, guiding and supporting nerve proliferation and migration. Cdc42 plays an important regulatory role in dynamic changes of the cytoskeleton. However, there is a little study referred to regulation and mechanism of Cdc42 on glial cells after peripheral nerve injury. The present study investigated the role of Cdc42 in the proliferation and migration of SCs after sciatic nerve injury. Cdc42 expression was tested, showing that the mRNA and protein expression levels of Cdc42 were significantly up-regulated after sciatic nerve injury. Then, we isolated and purified SCs from injuried sciatic nerve at day 7. The purified SCs were transfected with Cdc42 siRNA and pcDNA3.1-Cdc42, and the cell proliferation, cell cycle and migration were assessed. The results implied that Cdc42 siRNA remarkably inhibited Schwann cell proliferation and migration, and resulted in S phase arrest. While pcDNA3.1-Cdc42 showed a contrary effect. Besides, we also observed that Cdc42 siRNA down-regulated the protein expression of β-catenin, Cyclin D1, c-myc and p-p38, which were up-regulated by pcDNA3.1-Cdc42. Meanwhile, the inhibitor of Wnt/β-catenin and p38 MAPK signaling pathway IWP-2 and SB203580 significantly inhibited the effect of pcDNA3.1-Cdc42 on cell proliferation and migration. Overall, our data indicate that Cdc42 regulates Schwann cell proliferation and migration through Wnt/β-catenin and p38 MAPK signaling pathway after sciatic nerve injury, which provides further insights into the therapy of the sciatic nerve injury.

  13. Behaviour of oligodendrocytes and Schwann cells in an experimental model of toxic demyelination of the central nervous system Comportamento de oligodendrócitos e células de Schwann em modelo experimental de desmielinização tóxica do sistema nervoso central

    Directory of Open Access Journals (Sweden)

    Dominguita Lühers Graça

    2001-06-01

    Full Text Available Oligodendrocytes and Schwann cells are engaged in myelin production, maintenance and repairing respectively in the central nervous system (CNS and the peripheral nervous system (PNS. Whereas oligodendrocytes act only within the CNS, Schwann cells are able to invade the CNS in order to make new myelin sheaths around demyelinated axons. Both cells have some limitations in their activities, i.e. oligodendrocytes are post-mitotic cells and Schwann cells only get into the CNS in the absence of astrocytes. Ethidium bromide (EB is a gliotoxic chemical that when injected locally within the CNS, induce demyelination. In the EB model of demyelination, glial cells are destroyed early after intoxication and Schwann cells are free to approach the naked central axons. In normal Wistar rats, regeneration of lost myelin sheaths can be achieved as early as thirteen days after intoxication; in Wistar rats immunosuppressed with cyclophosphamide the process is delayed and in rats administered cyclosporine it may be accelerated. Aiming the enlightening of those complex processes, all events concerning the myelinating cells in an experimental model are herein presented and discussed.Oligodendrócitos e células de Schwann realizam a produção e manutenção das bainhas de mielina, respectivamente no sistema nervoso central (SNC e periférico (SNP. As células de Schwann, à diferença dos oligodendrócitos, são capazes de invadir o SNC para remielinizar axônios desmielinizados, sempre que os astrócitos tenham sido destruídos. O brometo de etídio é uma droga gliotóxica usada para induzir desmielinização com o desaparecimento precoce de astrócitos, de modo que as células de Schwann têm liberdade para invadir o SNC. Em ratos Wistar normais, a remielinização é detectada treze dias após desmielinização; em ratos Wistar imunossuprimidos com ciclofosfamida a reparação do tecido é tardia, enquanto que em animais tratados com ciclosporina ela

  14. Activated Schwann Cell-Like Cells on Aligned Fibrin-Poly(Lactic-Co-Glycolic Acid) Structures: A Novel Construct for Application in Peripheral Nerve Regeneration.

    Science.gov (United States)

    Schuh, Christina M A P; Morton, Tatjana J; Banerjee, Asmita; Grasl, Christian; Schima, Heinrich; Schmidhammer, Robert; Redl, Heinz; Ruenzler, Dominik

    2015-01-01

    Tissue engineering approaches in nerve regeneration search for ways to support gold standard therapy (autologous nerve grafts) and to improve results by bridging nerve defects with different kinds of conduits. In this study, we describe electrospinning of aligned fibrin-poly(lactic-co-glycolic acid) (PLGA) fibers in an attempt to create a biomimicking tissue-like material seeded with Schwann cell-like cells (SCLs) in vitro for potential use as an in vivo scaffold. Rat adipose-derived stem cells (rASCs) were differentiated into SCLs and evaluated with flow cytometry concerning their differentiation and activation status [S100b, P75, myelin-associated glycoprotein (MAG), and protein 0 (P0)]. After receiving the proliferation stimulus forskolin, SCLs expressed S100b and P75; comparable to native, activated Schwann cells, while cultured without forskolin, cells switched to a promyelinating phenotype and expressed S100b, MAG, and P0. Human fibrinogen and thrombin, blended with PLGA, were electrospun and the alignment and homogeneity of the fibers were proven by scanning electron microscopy. Electrospun scaffolds were seeded with SCLs and the formation of Büngner-like structures in SCLs was evaluated with phalloidin/propidium iodide staining. Carrier fibrin gels containing rASCs acted as a self-shaping matrix to form a tubular structure. In this study, we could show that rASCs can be differentiated into activated, proliferating SCLs and that these cells react to minimal changes in stimulus, switching to a promyelinating phenotype. Aligned electrospun fibrin-PLGA fibers promoted the formation of Büngner-like structures in SCLs, which also rolled the fibrin-PLGA matrix into a tubular scaffold. These in vitro findings favor further in vivo testing.

  15. Selective knockdown of mutant SOD1 in Schwann cells ameliorates disease in G85R mutant SOD1 transgenic mice.

    Science.gov (United States)

    Wang, Lijun; Pytel, Peter; Feltri, M Laura; Wrabetz, Lawrence; Roos, Raymond P

    2012-10-01

    Mutants of superoxide dismutase type 1 (mtSOD1) that have full dismutase activity (e.g., G37R) as well as none (e.g., G85R) cause familial amyotrophic lateral sclerosis (FALS), indicating that mtSOD1-induced FALS results from a toxicity rather than loss in SOD1 enzymatic activity. Still, it has remained unclear whether mtSOD1 dismutase activity can influence disease. A previous study demonstrated that Cre-mediated knockdown of G37R expression in Schwann cells (SCs) of G37R transgenic mice shortened the late phase of disease and survival. These results suggested that the neuroprotective effect of G37R expressed in SCs was greater than its toxicity, presumably because its dismutase activity counteracted reactive oxygen species (ROS). In order to further investigate this, we knocked down G85R in SCs by crossing G85R(flox) mice with myelin-protein-zero (P(0)):Cre mice, which express Cre recombinase in SCs. Knockdown of G85R in SCs of G85R mice delayed disease onset and extended survival indicating that G85R expression in SCs is neurotoxic. These results demonstrate differences in the effect on disease of dismutase active vs. inactive mtSOD1 suggesting that both a loss as well as gain in function of mtSOD1 influence FALS pathogenesis. The results suggest that mtSOD1-induced FALS treatment may have to be adjusted depending on the cell type targeted and particular mtSOD1 involved.

  16. Cell type- and isotype-specific expression and regulation of β-tubulins in primary olfactory ensheathing cells and Schwann cells in vitro.

    Science.gov (United States)

    Omar, Mohamed; Hansmann, Florian; Kreutzer, Robert; Kreutzer, Mihaela; Brandes, Gudrun; Wewetzer, Konstantin

    2013-05-01

    Olfactory ensheathing cells (OECs) and Schwann cells (SCs) are closely-related cell types with regeneration-promoting properties. Comparative gene expression analysis is particularly relevant since it may explain cell type-specific effects and guide the use of each cell type into special clinical applications. In the present study, we focused on β-tubulin isotype expression in primary adult canine glia as a translational large animal model. β-tubulins so far have been studied mainly in non-neuronal tumors and implied in tumorigenic growth. We show here that primary OECs and SCs expressed βII-V isotype mRNA. Interestingly, βIII-tubulin mRNA and protein expression was high in OECs and low in SCs, while fibroblast growth factor-2 (FGF-2) induced its down-regulation in both cell types to the same extent. This was in contrast to βV-tubulin mRNA which was similarly expressed in both cell types and unaltered by FGF-2. Immunocytochemical analysis revealed that OEC cultures contained a higher percentage of βIII-tubulin-positive cells compared to SC cultures. Addition of FGF-2 reduced the number of βIII-tubulin-positive cells in both cultures and significantly increased the percentage of cells with a multipolar morphology. Taken together, we demonstrate cell type-specific expression (βIII) and isotype-specific regulation (βIII, βV) of β-tubulin isotypes in OECs and SCs. While differential expression of βIII-tubulin in primary glial cell types with identical proliferative behaviour argues for novel functions unrelated to tumorigenic growth, strong βIII-tubulin expression in OECs may help to explain the specific properties of this glial cell type.

  17. 雪旺细胞在脊髓损伤中的研究进展%Research progress of Schwann cells in spinal cord injury

    Institute of Scientific and Technical Information of China (English)

    周孝斌; 李志忠; 孙国栋

    2014-01-01

    脊髓损伤(SCI)后的再生和修复仍是目前一大难点,目前研究认为其原因可归结为:神经元内在的再生能力不足、髓鞘再生困难、缺乏生长促进因子、在损伤区缺乏组织桥等,而雪旺细胞是周围神经的胶质细胞,包绕周围神经形成髓鞘,可分泌多种神经营养因子、细胞外基质、细胞粘附分子等,近几十年来,有关雪旺细胞治疗脊髓损伤的研究甚多,本文就此做一综述。%The regeneration and repair after spinal cord injury (SCI) remains a difficulty at present. It is be-lieved that the reasons can be attributed to:the shortcomings in the intrinsic regeneration ability of neurons, difficulty in myelin regeneration, lack of growth promoting factors, lack of organization and bridge in the damage zone. Schwann cells are glial cells of peripheral nerve, which wrap peripheral nerve myelination, secrete various neurotroph-ic factors, extracellular matrix, and cell adhesion molecules. In recent decades, a plethora of studies have focused on Schwann cell therapy for spinal cord injury. This review makes a summary on the research progress of Schwann cells.

  18. Enhanced noradrenergic axon regeneration into schwann cell-filled PVDF-TrFE conduits after complete spinal cord transection.

    Science.gov (United States)

    Lee, Yee-Shuan; Wu, Siliang; Arinzeh, Treena Livingston; Bunge, Mary Bartlett

    2017-02-01

    Schwann cell (SC) transplantation has been utilized for spinal cord repair and demonstrated to be a promising therapeutic strategy. In this study, we investigated the feasibility of combining SC transplantation with novel conduits to bridge the completely transected adult rat spinal cord. This is the first and initial study to evaluate the potential of using a fibrous piezoelectric polyvinylidene fluoride trifluoroethylene (PVDF-TrFE) conduit with SCs for spinal cord repair. PVDF-TrFE has been shown to enhance neurite growth in vitro and peripheral nerve repair in vivo. In this study, SCs adhered and proliferated when seeded onto PVDF-TrFE scaffolds in vitro. SCs and PVDF-TrFE conduits, consisting of random or aligned fibrous inner walls, were transplanted into transected rat spinal cords for 3 weeks to examine early repair. Glial fibrillary acidic protein (GFAP)(+) astrocyte processes and GFP (green fluorescent protein)-SCs were interdigitated at both rostral and caudal spinal cord/SC transplant interfaces in both types of conduits, indicative of permissivity to axon growth. More noradrenergic/DβH(+) (dopamine-beta-hydroxylase) brainstem axons regenerated across the transplant when greater numbers of GFAP(+) astrocyte processes were present. Aligned conduits promoted extension of DβH(+) axons and GFAP(+) processes farther into the transplant than random conduits. Sensory CGRP(+) (calcitonin gene-related peptide) axons were present at the caudal interface. Blood vessels formed throughout the transplant in both conduits. This study demonstrates that PVDF-TrFE conduits harboring SCs are promising for spinal cord repair and deserve further investigation. Biotechnol. Bioeng. 2017;114: 444-456. © 2016 Wiley Periodicals, Inc.

  19. Neutralization of schwann cell-secreted VEGF is protective to in vitro and in vivo experimental diabetic neuropathy.

    Directory of Open Access Journals (Sweden)

    Michela M Taiana

    Full Text Available The pathogenetic role of vascular endothelial growth factor (VEGF in long-term retinal and kidney complications of diabetes has been demonstrated. Conversely, little is known in diabetic neuropathy. We examined the modulation of VEGF pathway at mRNA and protein level on dorsal root ganglion (DRG neurons and Schwann cells (SC induced by hyperglycaemia. Moreover, we studied the effects of VEGF neutralization on hyperglycemic DRG neurons and streptozotocin-induced diabetic neuropathy. Our findings demonstrated that DRG neurons were not affected by the direct exposition to hyperglycaemia, whereas showed an impairment of neurite outgrowth ability when exposed to the medium of SC cultured in hyperglycaemia. This was mediated by an altered regulation of VEGF and FLT-1 receptors. Hyperglycaemia increased VEGF and FLT-1 mRNA without changing their intracellular protein levels in DRG neurons, decreased intracellular and secreted protein levels without changing mRNA level in SC, while reduced the expression of the soluble receptor sFLT-1 both in DRG neurons and SC. Bevacizumab, a molecule that inhibits VEGF activity preventing the interaction with its receptors, restored neurite outgrowth and normalized FLT-1 mRNA and protein levels in co-cultures. In diabetic rats, it both prevented and restored nerve conduction velocity and nociceptive thresholds. We demonstrated that hyperglycaemia early affected neurite outgrowth through the impairment of SC-derived VEGF/FLT-1 signaling and that the neutralization of SC-secreted VEGF was protective both in vitro and in vivo models of diabetic neuropathy.

  20. Opposing roles of PKA and EPAC in the cAMP-dependent regulation of schwann cell proliferation and differentiation [corrected].

    Directory of Open Access Journals (Sweden)

    Ketty Bacallao

    Full Text Available In Schwann cells (SCs, cyclic adenosine monophosphate (cAMP not only induces differentiation into a myelinating SC-related phenotype, but also synergistically enhances the mitogenic action of growth factors such as neuregulin. To better understand the molecular mechanism by which cAMP exerts these apparently contradictory functions, we investigated the role of the two main effectors of cAMP, protein kinase A (PKA and the exchange protein activated by cAMP (EPAC, on the proliferation and differentiation of both isolated and axon-related SCs. For these studies, a variety of PKA and EPAC agonists and antagonists were used, including pathway-selective analogs of cAMP and pharmacological inhibitors. Our studies indicated that the activity of PKA rather than EPAC was required for the adjuvant effect of cAMP on S-phase entry, whereas the activity of EPAC rather than PKA was required for SC differentiation and myelin formation. Even though selective EPAC activation had an overall anti-proliferative effect in SCs, it failed to drive the expression of Krox-20, a master regulator of myelination, and that of myelin-specific proteins and lipids, suggesting that EPAC activation was insufficient to drive a full differentiating response. Interestingly, inhibition of EPAC activity resulted in a drastic impairment of SC differentiation and myelin formation but not Krox-20 expression, which indicates an independent mechanism of Krox-20 regulation in response to cAMP. In conclusion, our data supports the idea that the outcome of cAMP signaling in SCs depends on the particular set of effectors activated. Whereas the mitogenic action of cAMP relies exclusively on PKA activity, the differentiating action of cAMP requires a PKA-independent (non-canonical cAMP-specific pathway that is partially transduced by EPAC.

  1. Opposing roles of PKA and EPAC in the cAMP-dependent regulation of schwann cell proliferation and differentiation [corrected].

    Science.gov (United States)

    Bacallao, Ketty; Monje, Paula V

    2013-01-01

    In Schwann cells (SCs), cyclic adenosine monophosphate (cAMP) not only induces differentiation into a myelinating SC-related phenotype, but also synergistically enhances the mitogenic action of growth factors such as neuregulin. To better understand the molecular mechanism by which cAMP exerts these apparently contradictory functions, we investigated the role of the two main effectors of cAMP, protein kinase A (PKA) and the exchange protein activated by cAMP (EPAC), on the proliferation and differentiation of both isolated and axon-related SCs. For these studies, a variety of PKA and EPAC agonists and antagonists were used, including pathway-selective analogs of cAMP and pharmacological inhibitors. Our studies indicated that the activity of PKA rather than EPAC was required for the adjuvant effect of cAMP on S-phase entry, whereas the activity of EPAC rather than PKA was required for SC differentiation and myelin formation. Even though selective EPAC activation had an overall anti-proliferative effect in SCs, it failed to drive the expression of Krox-20, a master regulator of myelination, and that of myelin-specific proteins and lipids, suggesting that EPAC activation was insufficient to drive a full differentiating response. Interestingly, inhibition of EPAC activity resulted in a drastic impairment of SC differentiation and myelin formation but not Krox-20 expression, which indicates an independent mechanism of Krox-20 regulation in response to cAMP. In conclusion, our data supports the idea that the outcome of cAMP signaling in SCs depends on the particular set of effectors activated. Whereas the mitogenic action of cAMP relies exclusively on PKA activity, the differentiating action of cAMP requires a PKA-independent (non-canonical) cAMP-specific pathway that is partially transduced by EPAC.

  2. Repair effect of Schwann cells modified by microgene pSVPoMcat on injured spinal cord in rats

    Institute of Scientific and Technical Information of China (English)

    陈礼刚; 高立达; 卢敏; 毛伯镛; 曾凡俊; 李开慧; 朴永旭

    2002-01-01

    To observe the repair effect of Schwann cells (SCs) modified by microgene pSVPoMcat on injured spinal cord in rats. Methods: Semi-transection injury at the level of T8 of spinal cord was made with cutting method on 120 Sprague Dawley (SD) rats. Then 40 rats implanted with SCs modified by microgene pSVPoMcat were taken as Group A,40 rats implanted with simple SCs as Group B and the other 40 rats were taken as the control group (Group C ). The functional recovery of the rats was observed through combined behavioral score ( CBS ) and cortical somatosensory evoked potential ( CSEP ), and the expression of the glial fibrillary acidic protein (GFAP) was measured with in situ hybridization and immunocytochemistry. At 3 months after operation, the rats were examined with magnetic resonance image (MRI), and the neurofilaments (NF) of the axons were stained with immunohistochemical method. Results: GFAP expression in Group A was significantly lower than that of the other 2 groups. MRI showed that the spinal signals in the injured area recovered fundamentally in Group A, didn't recover in Group B and malacia focus was found in Group C, which was same as the results of NF staining. Wave amplitudes in incubation periods in Group A and Group B tended to recover. It recovered to the normal level in Group A, which was similar to the results of CBS. Conclusions: SCs modified by microgene pSVPoMcat can inhibit GFAP expression, improve the growth of the axons and the functional recovery of neurons after spinal cord injury.

  3. Protective effect of hydrogen-rich medium against high glucose-induced apoptosis of Schwann cells in vitro.

    Science.gov (United States)

    Yu, Yang; Ma, Xiaoye; Yang, Tao; Li, Bo; Xie, Keliang; Liu, Daquan; Wang, Guolin; Yu, Yonghao

    2015-09-01

    Diabetic peripheral neuropathy (DPN) is considered to be one of the most prevalent and life threatening microvascular diabetic complications. DPN affects up to 50% of patients with diabetes mellitus and there are currently no efficacious therapeutic strategies available for its treatment. Previous studies have reported that oxidative stress and poly(ADP‑ribose) polymerase‑1 (PARP‑1) may be unifying factors for hyperglycemic injury. The aim of the present study was to investigate the protective effects of hydrogen‑rich medium (HM) on high glucose (HG)‑mediated oxidative stress, PARP‑1 activation and the apoptosis of Schwann cells (SCs) in vitro. The cells were divided into different groups, and were treated for 48 h. Cell viability and apoptosis were evaluated using Cell Counting kit‑8 and annexin V/propidium iodide assays, respectively. The concentrations of 8‑hydroxy‑2‑deoxyguanosine (8‑OHdG) and peroxynitrite (ONOO‑) were detected using an enzyme‑linked immunosorbent assay. The presence of intracellular oxygen free radicals was confirmed using flow cytometric analysis. Colorimetric assays were performed to determine the activity of caspase‑3, and western blotting was performed to detect the protein expression levels of PARP‑1, cleaved PARP‑1, PAR, apoptosis‑inducing factor (AIF), B‑cell lymphoma 2 (Bcl‑2) and Bcl‑2‑associated X protein. HG was found to induce severe oxidative stress and promote the caspase‑dependent and caspase‑independent apoptosis of SCs. Treatment with HM inhibited HG‑induced oxidative stress by suppressing hydroxyl and ONOO‑ production, levels of 8‑OHdG, caspase‑3 activity and apoptosis in the SCs. Furthermore, treatment with HM downregulated the HG‑induced release of PAR, the activation of PARP‑1 and nuclear translocation of AIF, and upregulated the expression of Bcl‑2 in the SCs. These results indicated that HM inhibited the HG‑induced‑oxidative stress‑associated caspase

  4. 吡咯喹啉醌对雪旺细胞增殖及NF-κB表达的影响%Effects of pyrroloquinoline quinone on proliferation and expression of NF-κB in cultured Schwann cells

    Institute of Scientific and Technical Information of China (English)

    贺斌; 刘世清; 李皓桓

    2009-01-01

    [Objective] To investigate the effects of pyrroloquinoline quinine (PQQ) on proliferation and expression of NF - kB of Schwann cells. [Methods] Schwann cells were cultured from sciatic nerves of SD rats in vitro. The Schwann cells were identified and purified by immunofluorescence of S-100 and Ara-C. Experimental group with was 100 nmol/L of PQQ and control group were set up. The expression of NF-kB in Schwann cells was determined by RT-PCR and Western blotting. [ Results] The expression of NF - kB were up - ragulated by PQQ in cultured Schwann cells (P<0.05).[Conclusion ] PQQ could promote the proliferation of Schwann cells and up-regulation of NF-rd3 play an important role in this process.%[目的]观察吡咯喹啉醌对雪旺细胞的增殖作用及其对体外培养雪旺细胞NF-κB表达的影响.[方法]新生鼠雪旺细胞体外原代培养及纯化,S-100免疫荧光标记鉴定雪旺细胞,设实验组与对照组,实验组吡咯喹啉醌的浓度为100 nmol/L;加药72 h后提取总mRNA及总蛋白进行RT-PCR和Western blot分析.[结果]采用RT-PCR和Western blot检测NF-κB的表达,结果均表明实验组表达较对照组高(P<0.05).[结论]吡咯喹啉醌可促进雪旺细胞增殖,NF-κB上调在吡咯喹啉醌促雪旺细胞增殖中起作用.

  5. Spatially- and temporally-controlled postnatal p53 knockdown cooperates with embryonic Schwann cell precursor Nf1 gene loss to promote malignant peripheral nerve sheath tumor formation.

    Science.gov (United States)

    Hirbe, Angela C; Dahiya, Sonika; Friedmann-Morvinski, Dinorah; Verma, Inder M; Clapp, D Wade; Gutmann, David H

    2016-02-16

    Malignant peripheral nerve sheath tumors (MPNSTs) are highly aggressive sarcomas that arise sporadically or in association with the Neurofibromatosis type 1 (NF1) cancer predisposition syndrome. In individuals with NF1, MPNSTs are hypothesized to arise from Nf1-deficient Schwann cell precursor cells following the somatic acquisition of secondary cooperating genetic mutations (e.g., p53 loss). To model this sequential genetic cooperativity, we coupled somatic lentivirus-mediated p53 knockdown in the adult right sciatic nerve with embryonic Schwann cell precursor Nf1 gene inactivation in two different Nf1 conditional knockout mouse strains. Using this approach, ~60% of mice with Periostin-Cre-mediated Nf1 gene inactivation (Periostin-Cre; Nf1(flox/flox) mice) developed tumors classified as low-grade MPNSTs following p53 knockdown (mean, 6 months). Similarly, ~70% of Nf1+/- mice with GFAP-Cre-mediated Nf1 gene inactivation (GFAP-Cre; Nf1(flox/null) mice) developed low-grade MPNSTs following p53 knockdown (mean, 3 months). In addition, wild-type and Nf1+/- mice with GFAP-Cre-mediated Nf1 loss develop MPNSTs following somatic p53 knockout with different latencies, suggesting potential influences of Nf1+/- stromal cells in MPNST pathogenesis. Collectively, this new MPNST model system permits the analysis of somatically-acquired events as well as tumor microenvironment signals that potentially cooperate with Nf1 loss in the development and progression of this deadly malignancy.

  6. Predegenerated Schwann cells–a novel prospect for cell therapy for glaucoma: neuroprotection, neuroregeneration and neuroplasticity

    OpenAIRE

    Adrian Smedowski; Xiaonan Liu; Marita Pietrucha-Dutczak; Iwona Matuszek; Markku Varjosalo; Joanna Lewin-Kowalik

    2016-01-01

    Glaucoma is an optic neuropathy that leads to irreversible blindness. Because the current therapies are not sufficient to protect against glaucoma-induced visual impairment, new treatment approaches are necessary to prevent disease progression. Cell transplantation techniques are currently considered to be among the most promising opportunities for nervous system damage treatment. The beneficial effects of undifferentiated cells have been investigated in experimental models of glaucoma, howev...

  7. A Combination Tissue Engineering Strategy for Schwann Cell-Induced Spinal Cord Repair

    Science.gov (United States)

    2016-10-01

    ZS, Dong SW, Chen WJ, Deng L, Wang YF, Ying DJ. 2012. Piezoelectric PU/PVDF electrospun scaffolds for wound healing applications. Colloids Surf B...conduit that can both enhance survival of transplanted cells and promote axon regeneration is needed for an effective therapy for the injured spinal cord...Kown BK. 2011. A systematic review of cellular transplantation therapies for spinal cord injury. J Neurotrauma 28(8):1611–1682. Valentini RF, Vargo

  8. The analgesic effect on neuropathic pain of retrogradely transported botulinum neurotoxin A involves Schwann cells and astrocytes.

    Directory of Open Access Journals (Sweden)

    Sara Marinelli

    Full Text Available In recent years a growing debate is about whether botulinum neurotoxins are retrogradely transported from the site of injection. Immunodetection of cleaved SNAP-25 (cl-SNAP-25, the protein of the SNARE complex targeted by botulinum neurotoxin serotype A (BoNT/A, could represent an excellent approach to investigate the mechanism of action on the nociceptive pathways at peripheral and/or central level. After peripheral administration of BoNT/A, we analyzed the expression of cl-SNAP-25, from the hindpaw's nerve endings to the spinal cord, together with the behavioral effects on neuropathic pain. We used the chronic constriction injury of the sciatic nerve in CD1 mice as animal model of neuropathic pain. We evaluated immunostaining of cl-SNAP-25 in the peripheral nerve endings, along the sciatic nerve, in dorsal root ganglia and in spinal dorsal horns after intraplantar injection of saline or BoNT/A, alone or colocalized with either glial fibrillar acidic protein, GFAP, or complement receptor 3/cluster of differentiation 11b, CD11b, or neuronal nuclei, NeuN, depending on the area investigated. Immunofluorescence analysis shows the presence of the cl-SNAP-25 in all tissues examined, from the peripheral endings to the spinal cord, suggesting a retrograde transport of BoNT/A. Moreover, we performed in vitro experiments to ascertain if BoNT/A was able to interact with the proliferative state of Schwann cells (SC. We found that BoNT/A modulates the proliferation of SC and inhibits the acetylcholine release from SC, evidencing a new biological effect of the toxin and further supporting the retrograde transport of the toxin along the nerve and its ability to influence regenerative processes. The present results strongly sustain a combinatorial action at peripheral and central neural levels and encourage the use of BoNT/A for the pathological pain conditions difficult to treat in clinical practice and dramatically impairing patients' quality of life.

  9. The Analgesic Effect on Neuropathic Pain of Retrogradely Transported botulinum Neurotoxin A Involves Schwann Cells and Astrocytes

    Science.gov (United States)

    Ricordy, Ruggero; Uggenti, Carolina; Tata, Ada Maria; Luvisetto, Siro; Pavone, Flaminia

    2012-01-01

    In recent years a growing debate is about whether botulinum neurotoxins are retrogradely transported from the site of injection. Immunodetection of cleaved SNAP-25 (cl-SNAP-25), the protein of the SNARE complex targeted by botulinum neurotoxin serotype A (BoNT/A), could represent an excellent approach to investigate the mechanism of action on the nociceptive pathways at peripheral and/or central level. After peripheral administration of BoNT/A, we analyzed the expression of cl-SNAP-25, from the hindpaw’s nerve endings to the spinal cord, together with the behavioral effects on neuropathic pain. We used the chronic constriction injury of the sciatic nerve in CD1 mice as animal model of neuropathic pain. We evaluated immunostaining of cl-SNAP-25 in the peripheral nerve endings, along the sciatic nerve, in dorsal root ganglia and in spinal dorsal horns after intraplantar injection of saline or BoNT/A, alone or colocalized with either glial fibrillar acidic protein, GFAP, or complement receptor 3/cluster of differentiation 11b, CD11b, or neuronal nuclei, NeuN, depending on the area investigated. Immunofluorescence analysis shows the presence of the cl-SNAP-25 in all tissues examined, from the peripheral endings to the spinal cord, suggesting a retrograde transport of BoNT/A. Moreover, we performed in vitro experiments to ascertain if BoNT/A was able to interact with the proliferative state of Schwann cells (SC). We found that BoNT/A modulates the proliferation of SC and inhibits the acetylcholine release from SC, evidencing a new biological effect of the toxin and further supporting the retrograde transport of the toxin along the nerve and its ability to influence regenerative processes. The present results strongly sustain a combinatorial action at peripheral and central neural levels and encourage the use of BoNT/A for the pathological pain conditions difficult to treat in clinical practice and dramatically impairing patients’ quality of life. PMID:23110146

  10. Chitosan Degradation Products Promote Nerve Regeneration by Stimulating Schwann Cell Proliferation via miR-27a/FOXO1 Axis.

    Science.gov (United States)

    Wang, Yongjun; Zhao, Yahong; Sun, Cheng; Hu, Wen; Zhao, Jing; Li, Guicai; Zhang, Luzhong; Liu, Mei; Liu, Yan; Ding, Fei; Yang, Yumin; Gu, Xiaosong

    2016-01-01

    Natural polysaccharides are biomaterials widely used for constructing scaffolds in tissue engineering. While natural polysaccharides have been shown to robustly promote tissue regeneration, the underlying molecular mechanism remains largely unknown. Here, we show that chitooligosaccharides (COS), the intermediate products of chitosan degradation, stimulate peripheral nerve regeneration in rats. Our experiment also shows that COS stimulate the proliferation of Schwann cells (SCs) during nerve regeneration. By analyzing the transcriptome and gene regulatory network, we identified the miR-27a/FOXO1 axis as the main signaling pathway for mediating the proliferative effects of COS on SCs. COS increase the expression level of miR-27a and cause a reduction of FOXO1, which subsequently accelerates the cell cycle and stimulates SC proliferation to stimulate nerve regeneration. These findings define a basic pathway for oligosaccharides-mediated cell proliferation and reveal a novel aspect of polysaccharide biomaterials in tissue engineering.

  11. A Silk Fibroin/Collagen Nerve Scaffold Seeded with a Co-Culture of Schwann Cells and Adipose-Derived Stem Cells for Sciatic Nerve Regeneration.

    Directory of Open Access Journals (Sweden)

    Yunqiang Xu

    Full Text Available As a promising alternative to autologous nerve grafts, tissue-engineered nerve grafts have been extensively studied as a way to bridge peripheral nerve defects and guide nerve regeneration. The main difference between autogenous nerve grafts and tissue-engineered nerve grafts is the regenerative microenvironment formed by the grafts. If an appropriate regenerative microenvironment is provided, the repair of a peripheral nerve is feasible. In this study, to mimic the body's natural regenerative microenvironment closely, we co-cultured Schwann cells (SCs and adipose-derived stem cells (ADSCs as seed cells and introduced them into a silk fibroin (SF/collagen scaffold to construct a tissue-engineered nerve conduit (TENC. Twelve weeks after the three different grafts (plain SF/collagen scaffold, TENC, and autograft were transplanted to bridge 1-cm long sciatic nerve defects in rats, a series of electrophysiological examinations and morphological analyses were performed to evaluate the effect of the tissue-engineered nerve grafts on peripheral nerve regeneration. The regenerative outcomes showed that the effect of treatment with TENCs was similar to that with autologous nerve grafts but superior to that with plain SF/collagen scaffolds. Meanwhile, no experimental animals had inflammation around the grafts. Based on this evidence, our findings suggest that the TENC we developed could improve the regenerative microenvironment and accelerate nerve regeneration compared to plain SF/collagen and may serve as a promising strategy for peripheral nerve repair.

  12. A Silk Fibroin/Collagen Nerve Scaffold Seeded with a Co-Culture of Schwann Cells and Adipose-Derived Stem Cells for Sciatic Nerve Regeneration.

    Science.gov (United States)

    Xu, Yunqiang; Zhang, Zhenhui; Chen, Xuyi; Li, Ruixin; Li, Dong; Feng, Shiqing

    2016-01-01

    As a promising alternative to autologous nerve grafts, tissue-engineered nerve grafts have been extensively studied as a way to bridge peripheral nerve defects and guide nerve regeneration. The main difference between autogenous nerve grafts and tissue-engineered nerve grafts is the regenerative microenvironment formed by the grafts. If an appropriate regenerative microenvironment is provided, the repair of a peripheral nerve is feasible. In this study, to mimic the body's natural regenerative microenvironment closely, we co-cultured Schwann cells (SCs) and adipose-derived stem cells (ADSCs) as seed cells and introduced them into a silk fibroin (SF)/collagen scaffold to construct a tissue-engineered nerve conduit (TENC). Twelve weeks after the three different grafts (plain SF/collagen scaffold, TENC, and autograft) were transplanted to bridge 1-cm long sciatic nerve defects in rats, a series of electrophysiological examinations and morphological analyses were performed to evaluate the effect of the tissue-engineered nerve grafts on peripheral nerve regeneration. The regenerative outcomes showed that the effect of treatment with TENCs was similar to that with autologous nerve grafts but superior to that with plain SF/collagen scaffolds. Meanwhile, no experimental animals had inflammation around the grafts. Based on this evidence, our findings suggest that the TENC we developed could improve the regenerative microenvironment and accelerate nerve regeneration compared to plain SF/collagen and may serve as a promising strategy for peripheral nerve repair.

  13. Stringent comparative sequence analysis reveals SOX10 as a putative inhibitor of glial cell differentiation.

    Science.gov (United States)

    Gopinath, Chetna; Law, William D; Rodríguez-Molina, José F; Prasad, Arjun B; Song, Lingyun; Crawford, Gregory E; Mullikin, James C; Svaren, John; Antonellis, Anthony

    2016-11-07

    The transcription factor SOX10 is essential for all stages of Schwann cell development including myelination. SOX10 cooperates with other transcription factors to activate the expression of key myelin genes in Schwann cells and is therefore a context-dependent, pro-myelination transcription factor. As such, the identification of genes regulated by SOX10 will provide insight into Schwann cell biology and related diseases. While genome-wide studies have successfully revealed SOX10 target genes, these efforts mainly focused on myelinating stages of Schwann cell development. We propose that less-biased approaches will reveal novel functions of SOX10 outside of myelination. We developed a stringent, computational-based screen for genome-wide identification of SOX10 response elements. Experimental validation of a pilot set of predicted binding sites in multiple systems revealed that SOX10 directly regulates a previously unreported alternative promoter at SOX6, which encodes a transcription factor that inhibits glial cell differentiation. We further explored the utility of our computational approach by combining it with DNase-seq analysis in cultured Schwann cells and previously published SOX10 ChIP-seq data from rat sciatic nerve. Remarkably, this analysis enriched for genomic segments that map to loci involved in the negative regulation of gliogenesis including SOX5, SOX6, NOTCH1, HMGA2, HES1, MYCN, ID4, and ID2. Functional studies in Schwann cells revealed that: (1) all eight loci are expressed prior to myelination and down-regulated subsequent to myelination; (2) seven of the eight loci harbor validated SOX10 binding sites; and (3) seven of the eight loci are down-regulated upon repressing SOX10 function. Our computational strategy revealed a putative novel function for SOX10 in Schwann cells, which suggests a model where SOX10 activates the expression of genes that inhibit myelination during non-myelinating stages of Schwann cell development. Importantly, the

  14. Human Schwann cells exhibit long-term cell survival, are not tumorigenic and promote repair when transplanted into the contused spinal cord.

    Science.gov (United States)

    Bastidas, Johana; Athauda, Gagani; De La Cruz, Gabriela; Chan, Wai-Man; Golshani, Roozbeh; Berrocal, Yerko; Henao, Martha; Lalwani, Anil; Mannoji, Chikato; Assi, Mazen; Otero, P Anthony; Khan, Aisha; Marcillo, Alexander E; Norenberg, Michael; Levi, Allan D; Wood, Patrick M; Guest, James D; Dietrich, W Dalton; Bartlett Bunge, Mary; Pearse, Damien D

    2017-08-01

    The transplantation of rodent Schwann cells (SCs) provides anatomical and functional restitution in a variety of spinal cord injury (SCI) models, supporting the recent translation of SCs to phase 1 clinical trials for human SCI. Whereas human (Hu)SCs have been examined experimentally in a complete SCI transection paradigm, to date the reported behavior of SCs when transplanted after a clinically relevant contusive SCI has been restricted to the use of rodent SCs. Here, in a xenotransplant, contusive SCI paradigm, the survival, biodistribution, proliferation and tumorgenicity as well as host responses to HuSCs, cultured according to a protocol analogous to that developed for clinical application, were investigated. HuSCs persisted within the contused nude rat spinal cord through 6 months after transplantation (longest time examined), exhibited low cell proliferation, displayed no evidence of tumorigenicity and showed a restricted biodistribution to the lesion. Neuropathological examination of the CNS revealed no adverse effects of HuSCs. Animals exhibiting higher numbers of surviving HuSCs within the lesion showed greater volumes of preserved white matter and host rat SC and astrocyte ingress as well as axon ingrowth and myelination. These results demonstrate the safety of HuSCs when employed in a clinically relevant experimental SCI paradigm. Further, signs of a potentially positive influence of HuSC transplants on host tissue pathology were observed. These findings show that HuSCs exhibit a favorable toxicity profile for up to 6 months after transplantation into the contused rat spinal cord, an important outcome for FDA consideration of their use in human clinical trials. © 2017 Wiley Periodicals, Inc.

  15. RSC96 Schwann Cell Proliferation and Survival Induced by Dilong through PI3K/Akt Signaling Mediated by IGF-I

    Directory of Open Access Journals (Sweden)

    Yung-Ming Chang

    2011-01-01

    Full Text Available Schwann cell proliferation is critical for the regeneration of injured nerves. Dilongs are widely used in Chinese herbal medicine to remove stasis and stimulate wound-healing functions. Exactly how this Chinese herbal medicine promotes tissue survival remains unclear. The aim of the present study was to investigate the molecular mechanisms by which Dilong promote neuron regeneration. Our results show that treatment with extract of Dilong induces the phosphorylation of the insulin-like growth factor-I (IGF-I-mediated phosphatidylinositol 3-kinase/serine-threonine kinase (PI3K/Akt pathway, and activates protein expression of cell nuclear antigen (PCNA in a time-dependent manner. Cell cycle analysis showed that G1 transits into the S phase in 12–16 h, and S transits into the G2 phase 20 h after exposure to earthworm extract. Strong expression of cyclin D1, cyclin E and cyclin A occurs in a time-dependent manner. Small interfering RNA (siRNA-mediated knockdown of PI3K significantly reduced PI3K protein expression levels, resulting in Bcl2 survival factor reduction and a marked blockage of G1 to S transition in proliferating cells. These results demonstrate that Dilong promotes the proliferation and survival of RSC96 cells via IGF-I signaling. The mechanism is mainly dependent on the PI3K protein.

  16. Acute Putrescine Supplementation with Schwann Cell Implantation Improves Sensory and Serotonergic Axon Growth and Functional Recovery in Spinal Cord Injured Rats.

    Science.gov (United States)

    Iorgulescu, J Bryan; Patel, Samik P; Louro, Jack; Andrade, Christian M; Sanchez, Andre R; Pearse, Damien D

    2015-01-01

    Schwann cell (SC) transplantation exhibits significant potential for spinal cord injury (SCI) repair and its use as a therapeutic modality has now progressed to clinical trials for subacute and chronic human SCI. Although SC implants provide a receptive environment for axonal regrowth and support functional recovery in a number of experimental SCI models, axonal regeneration is largely limited to local systems and the behavioral improvements are modest without additional combinatory approaches. In the current study we investigated whether the concurrent delivery of the polyamine putrescine, started either 30 min or 1 week after SCI, could enhance the efficacy of SCs when implanted subacutely (1 week after injury) into the contused rat spinal cord. Polyamines are ubiquitous organic cations that play an important role in the regulation of the cell cycle, cell division, cytoskeletal organization, and cell differentiation. We show that the combination of putrescine with SCs provides a significant increase in implant size, an enhancement in axonal (sensory and serotonergic) sparing and/or growth, and improved open field locomotion after SCI, as compared to SC implantation alone. These findings demonstrate that polyamine supplementation can augment the effectiveness of SCs when used as a therapeutic approach for subacute SCI repair.

  17. Exclusive expression of the Rab11 effector SH3TC2 in Schwann cells links integrin-α6 and myelin maintenance to Charcot-Marie-Tooth disease type 4C.

    Science.gov (United States)

    Vijay, Sauparnika; Chiu, Meagan; Dacks, Joel B; Roberts, Rhys C

    2016-07-01

    Charcot-Marie-Tooth disease type 4C (CMT4C) is one of the commonest autosomal recessive inherited peripheral neuropathies and is associated with mutations in the Rab11 effector, SH3TC2. Disruption of the SH3TC2-Rab11 interaction is the molecular abnormality underlying this disease. However, why SH3TC2 mutations cause an isolated demyelinating neuropathy remains unanswered. Here we show that SH3TC2 is an exclusive Schwann cell protein expressed late in myelination and is downregulated following denervation suggesting a functional role in myelin sheath maintenance. We support our data with an evolutionary cell biological analysis showing that the SH3TC2 gene, and its paralogue SH3TC1, are derived from an ancestral homologue, the duplication of which occurred in the common ancestor of jawed vertebrates, coincident with the appearance of Schwann cells and peripheral axon myelination. Furthermore, we report that SH3TC2 associates with integrin-α6, suggesting that aberrant Rab11-dependent endocytic trafficking of this critical laminin receptor in myelinated Schwann cells is connected to the demyelination seen in affected nerves. Our study therefore highlights the inherent evolutionary link between SH3TC2 and peripheral nerve myelination, pointing also towards a molecular mechanism underlying the specific demyelinating neuropathy that characterizes CMT4C.

  18. Schwann cell-specific JAM-C-deficient mice reveal novel expression and functions for JAM-C in peripheral nerves.

    Science.gov (United States)

    Colom, Bartomeu; Poitelon, Yannick; Huang, Wenlong; Woodfin, Abigail; Averill, Sharon; Del Carro, Ubaldo; Zambroni, Desirée; Brain, Susan D; Perretti, Mauro; Ahluwalia, Amrita; Priestley, John V; Chavakis, Triantafyllos; Imhof, Beat A; Feltri, M Laura; Nourshargh, Sussan

    2012-03-01

    Junctional adhesion molecule-C (JAM-C) is an adhesion molecule expressed at junctions between adjacent endothelial and epithelial cells and implicated in multiple inflammatory and vascular responses. In addition, we recently reported on the expression of JAM-C in Schwann cells (SCs) and its importance for the integrity and function of peripheral nerves. To investigate the role of JAM-C in neuronal functions further, mice with a specific deletion of JAM-C in SCs (JAM-C SC KO) were generated. Compared to wild-type (WT) controls, JAM-C SC KO mice showed electrophysiological defects, muscular weakness, and hypersensitivity to mechanical stimuli. In addressing the underlying cause of these defects, nerves from JAM-C SC KO mice were found to have morphological defects in the paranodal region, exhibiting increased nodal length as compared to WTs. The study also reports on previously undetected expressions of JAM-C, namely on perineural cells, and in line with nociception defects of the JAM-C SC KO animals, on finely myelinated sensory nerve fibers. Collectively, the generation and characterization of JAM-C SC KO mice has provided unequivocal evidence for the involvement of SC JAM-C in the fine organization of peripheral nerves and in modulating multiple neuronal responses.

  19. Hypoxia-Induced Upregulation of miR-132 Promotes Schwann Cell Migration After Sciatic Nerve Injury by Targeting PRKAG3.

    Science.gov (United States)

    Yao, Chun; Shi, Xiangxiang; Zhang, Zhanhu; Zhou, Songlin; Qian, Tianmei; Wang, Yaxian; Ding, Fei; Gu, Xiaosong; Yu, Bin

    2016-10-01

    Following peripheral nerve injury, hypoxia is formed as a result of defects in blood supply at the injury site. Despite accumulating evidence on the effects of microRNAs (miRNAs) on phenotype modulation of Schwann cells (SCs) after peripheral nerve injury, the impact of hypoxia on SC behaviors through miRNAs during peripheral nerve regeneration has not been estimated. In this study, we confirmed our previous microarray data on the upregulation of miR-132 after sciatic nerve injury in rats and observed that overexpression of miR-132 significantly promoted cell migration of primary cultured SCs. Interestingly, hypoxia-increased expression of miR-132 also enhanced SC migration while inhibition of miR-132 suppressed hypoxia-induced increase in SC migration. miR-132 downregulated PRKAG3 through binding to its 3'-UTR, and PRKAG3 knockdown compromised the reducing effect of miR-132 inhibition on SC migration under normal or hypoxia condition. Moreover, in vivo injection of miR-132 agomir into rats with sciatic nerve transection accelerated SC migration from the proximal to distal stump. Overall, our results suggest that the hypoxia-induced upregulation of miR-132 could promote SC migration and facilitate peripheral nerve regeneration.

  20. Axonal regeneration and remyelination evaluation of chitosan/gelatin-based nerve guide combined with transforming growth factor-β1 and Schwann cells.

    Science.gov (United States)

    Nie, Xin; Deng, Manjing; Yang, Maojin; Liu, Luchuan; Zhang, Yongjie; Wen, Xiujie

    2014-01-01

    Despite efforts in peripheral nerve injury and regeneration, it is difficult to achieve a functional recovery following extended peripheral nerve lesions. Even if artificial nerve conduit, cell components and growth factors can enhance nerve regeneration, integration in peripheral nerve repair and regeneration remains yet to be explored. For this study, we used chitosan/gelatin nerve graft constructed with collagenous matrices as a vehicle for Schwann cells and transforming growth factor-β1 to bridge a 10-mm gap of the sciatic nerve and explored the feasibility of improving regeneration and reinnervation in rats. The nerve regeneration was assessed with functional recovery, electrophysiological test, retrograde labeling, and immunohistochemistry analysis during the post-operative period of 16 weeks. The results showed that the internal sides of the conduits were compact enough to prevent the connective tissues from ingrowth. Nerve conduction velocity, average regenerated myelin area, and myelinated axon count were similar to those treated with autograft (p > 0.05) but significantly higher than those bridged with chitosan/gelatin nerve graft alone (p regeneration and remyelination. A designed graft incorporating all of the tissue-engineering strategies for peripheral nerve regeneration may provide great progress in tissue engineering for nerve repair.

  1. Expression of NF-кB in Schwann cells and its effect on motor neuron apoptosis in spinal cord following sciatic nerves injury in rats

    Institute of Scientific and Technical Information of China (English)

    WANG Yong-tang; LU Xiu-min; YU Ying; YANG Yan-hong; GAO Jie

    2007-01-01

    Objective:To explore the expression of nuclear factor-kappa B (NF-кB) in Schwann cells (SCs) and its effect on motor neuron apoptosis in spinal cord following sciatic nerves injury in adult rats. Methods:Thirty-six adult Sprague-Dawley (SD) rats were divided randomly into normal control group (n=6),and sciatic nerves crushing group (n=30),and the later was further equally randomized into 5 nerves were examined by immunohistochemistry staining,and the apoptosis of motor neurons in spinalcord of lumbar 4 to lumbar 6(L4-L6)was investigated by terminal deoxynucleotidyl transferase mediated dUTP-biotin nick end labeling (TUNEL) assay.Both were quantitated by image analysis.Results:In the normal control group (P<0.05,P<0.01).At 1 d after sciatic nerves crushing,the expression of served in the time-course on motor neuron apoptosis after sciatic nerves injury.Correlation analyses refollowing sciatic nerves injury(r=0.976 0,P<0.01).Conclusion:After injury of sciatic nerves,the presence and up-regulation of NF-κB in SCs may be involved in motor neuron apoptosis in L4-L6 spinal cord.

  2. mTORC1 Controls PNS Myelination along the mTORC1-RXRγ-SREBP-Lipid Biosynthesis Axis in Schwann Cells

    Directory of Open Access Journals (Sweden)

    Camilla Norrmén

    2014-10-01

    Full Text Available Myelin formation during peripheral nervous system (PNS development, and reformation after injury and in disease, requires multiple intrinsic and extrinsic signals. Akt/mTOR signaling has emerged as a major player involved, but the molecular mechanisms and downstream effectors are virtually unknown. Here, we have used Schwann-cell-specific conditional gene ablation of raptor and rictor, which encode essential components of the mTOR complexes 1 (mTORC1 and 2 (mTORC2, respectively, to demonstrate that mTORC1 controls PNS myelination during development. In this process, mTORC1 regulates lipid biosynthesis via sterol regulatory element-binding proteins (SREBPs. This course of action is mediated by the nuclear receptor RXRγ, which transcriptionally regulates SREBP1c downstream of mTORC1. Absence of mTORC1 causes delayed myelination initiation as well as hypomyelination, together with abnormal lipid composition and decreased nerve conduction velocity. Thus, we have identified the mTORC1-RXRγ-SREBP axis controlling lipid biosynthesis as a major contributor to proper peripheral nerve function.

  3. mTORC1 controls PNS myelination along the mTORC1-RXRγ-SREBP-lipid biosynthesis axis in Schwann cells.

    Science.gov (United States)

    Norrmén, Camilla; Figlia, Gianluca; Lebrun-Julien, Frédéric; Pereira, Jorge A; Trötzmüller, Martin; Köfeler, Harald C; Rantanen, Ville; Wessig, Carsten; van Deijk, Anne-Lieke F; Smit, August B; Verheijen, Mark H G; Rüegg, Markus A; Hall, Michael N; Suter, Ueli

    2014-10-23

    Myelin formation during peripheral nervous system (PNS) development, and reformation after injury and in disease, requires multiple intrinsic and extrinsic signals. Akt/mTOR signaling has emerged as a major player involved, but the molecular mechanisms and downstream effectors are virtually unknown. Here, we have used Schwann-cell-specific conditional gene ablation of raptor and rictor, which encode essential components of the mTOR complexes 1 (mTORC1) and 2 (mTORC2), respectively, to demonstrate that mTORC1 controls PNS myelination during development. In this process, mTORC1 regulates lipid biosynthesis via sterol regulatory element-binding proteins (SREBPs). This course of action is mediated by the nuclear receptor RXRγ, which transcriptionally regulates SREBP1c downstream of mTORC1. Absence of mTORC1 causes delayed myelination initiation as well as hypomyelination, together with abnormal lipid composition and decreased nerve conduction velocity. Thus, we have identified the mTORC1-RXRγ-SREBP axis controlling lipid biosynthesis as a major contributor to proper peripheral nerve function. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

  4. Co-transplantation of neural stem cells and Schwann cells within poly (L-lactic-co-glycolic acid) scaffolds facilitates axonal regeneration in hemisected rat spinal cord

    Institute of Scientific and Technical Information of China (English)

    XIA Lei; WAN Hong; HAO Shu-yu; LI De-zhi; CHEN Gang; GAO Chuan-chuan; LI Jun-hua

    2013-01-01

    Background Various tissue engineering strategies have been developed to facilitate axonal regeneration after spinal cord injury.This study aimed to investigate whether neural stem cells (NSCs) could survive in poly(L-lactic-co-glycolic acid) (PLGA) scaffolds and,when cografted with Schwann cells (SCs),could be induced to differentiate towards neurons which form synaptic connection and eventually facilitate axonal regeneration and myelination and motor function.Methods NSCs and SCs which were seeded within the directional PLGA scaffolds were implanted in hemisected adult rat spinal cord.Control rats were similarly injured and implanted of scaffolds with or without NSCs.Survival,migration,differentiation,synaptic formation of NSCs,axonal regeneration and myelination and motor function were analyzed.Student's t test was used to determine differences in surviving percentage of NSCs.One-way analysis of variance (ANOVA) was used to determine the differences in the number of axons myelinated in the scaffolds,the mean latency and amplitude of cortical motor evoked potentials (CMEPs) and Basso,Beattie & Bresnahan locomotor rating scale (BBB) score.The X2 test was used to determine the differences in recovery percentage of CMEPs.Results NSCs survived,but the majority migrated into adjacent host cord and died mostly.Survival rate of NSCs with SCs was higher than that of NSCs without SCs ((1.7831±0.0402)% vs.(1.4911±0.0313)%,P <0.001).Cografted with SCs,NSCs were induced to differentiate towards neurons and might form synaptic connection.The mean number of myelinated axons in PLGA+NSCs+SCs group was more than that in PLGA+NSCs group and in PLGA group ((110.25±30.46) vs.(18.25±3.30) and (11.25±5.54),P <0.01).The percentage of CMEPs recovery in PLGA+NSCs+SCs group was higher than in the other groups (84.8% vs.50.0% and 37.5%,P <0.05).The amplitude of CMEPs in PLGA+NSCs+SCs group was higher than in the other groups ((1452.63±331.70) μV vs.(428.84±193.01)

  5. Design of super-elastic biodegradable scaffolds with longitudinally oriented microchannels and optimization of the channel size for Schwann cell migration

    Directory of Open Access Journals (Sweden)

    Koichiro Uto, Takanari Muroya, Michio Okamoto, Hiroyuki Tanaka, Tsuyoshi Murase, Mitsuhiro Ebara and Takao Aoyagi

    2012-01-01

    Full Text Available We newly designed super-elastic biodegradable scaffolds with longitudinally oriented microchannels for repair and regeneration of peripheral nerve defects. Four-armed poly(ε-caprolactone-co-D,L-lactides (P(CL-co-DLLAs were synthesized by ring-opening copolymerization of CL and DLLA from terminal hydroxyl groups of pentaerythritol, and acryloyl chloride was then reacted with the ends of the chains. The end-functionalized P(CL-co-DLLA was crosslinked in a cylindrical mold in the presence of longitudinally oriented silica fibers as the templates, which were later dissolved by hydrofluoric acid. The elastic moduli of the crosslinked P(CL-co-DLLAs were controlled between 10−1 and 102 MPa at 37 °C, depending on the composition. The scaffolds could be elongated to 700% of their original size without fracture or damage ('super-elasticity'. Scanning electron microscopy images revealed that well-defined and highly aligned multiple channels consistent with the mold design were produced in the scaffolds. Owing to their elastic nature, the microchannels in the scaffolds did not collapse when they were bent to 90°. To evaluate the effect of the channel diameter on Schwann cell migration, microchannels were also fabricated in transparent poly(dimethylsiloxane, allowing observation of cell migration. The migration speed increased with channel size, but the Young's modulus of the scaffold decreased as the channel diameter increased. These findings may serve as the basis for designing tissue-engineering scaffolds for nerve regeneration and investigating the effects of the geometrical and dimensional properties on axonal outgrowth.

  6. Design of super-elastic biodegradable scaffolds with longitudinally oriented microchannels and optimization of the channel size for Schwann cell migration

    Science.gov (United States)

    Uto, Koichiro; Muroya, Takanari; Okamoto, Michio; Tanaka, Hiroyuki; Murase, Tsuyoshi; Ebara, Mitsuhiro; Aoyagi, Takao

    2012-12-01

    We newly designed super-elastic biodegradable scaffolds with longitudinally oriented microchannels for repair and regeneration of peripheral nerve defects. Four-armed poly(ɛ-caprolactone-co-D,L-lactide)s (P(CL-co-DLLA)s) were synthesized by ring-opening copolymerization of CL and DLLA from terminal hydroxyl groups of pentaerythritol, and acryloyl chloride was then reacted with the ends of the chains. The end-functionalized P(CL-co-DLLA) was crosslinked in a cylindrical mold in the presence of longitudinally oriented silica fibers as the templates, which were later dissolved by hydrofluoric acid. The elastic moduli of the crosslinked P(CL-co-DLLA)s were controlled between 10-1 and 102 MPa at 37 °C, depending on the composition. The scaffolds could be elongated to 700% of their original size without fracture or damage (‘super-elasticity’). Scanning electron microscopy images revealed that well-defined and highly aligned multiple channels consistent with the mold design were produced in the scaffolds. Owing to their elastic nature, the microchannels in the scaffolds did not collapse when they were bent to 90°. To evaluate the effect of the channel diameter on Schwann cell migration, microchannels were also fabricated in transparent poly(dimethylsiloxane), allowing observation of cell migration. The migration speed increased with channel size, but the Young's modulus of the scaffold decreased as the channel diameter increased. These findings may serve as the basis for designing tissue-engineering scaffolds for nerve regeneration and investigating the effects of the geometrical and dimensional properties on axonal outgrowth.

  7. Calcitriol prevents peripheral RSC96 Schwann neural cells from high glucose & methylglyoxal-induced injury through restoration of CBS/H2S expression.

    Science.gov (United States)

    Zhang, Hui; Zhuang, Xiao-dong; Meng, Fu-hui; Chen, Li; Dong, Xiao-bian; Liu, Guo-Hui; Li, Jian-hua; Dong, Qi; Xu, Ji-de; Yang, Chun-tao

    2016-01-01

    A meta-analysis has suggested that vitamin D deficiency is involved in diabetic peripheral neuropathy (DPN) and the levels of hydrogen sulfide (H2S) are also decreased in type 2 diabetes. The injection of vitamin D induces cystathionine-β-synthase (CBS) expression and H2S generation. However, it remains unclear whether the supplementation of vitamin D prevents DPN through improvement of CBS/H2S expression. In the present study, RSC96 cells, a rat Schwann cell line, were exposed to high glucose and methylglyoxal (HG&MG) to simulate diabetic peripheral nerve injury in vivo. Before the exposure to HG&MG, the cells were preconditioned with calcitriol (CCT), an active form of vitamin D, and then CCT-mediated neuroprotection was investigated in respect of cellular viability, superoxide anion (O2(-)) generation, inducible nitric oxide (NO) synthase (iNOS)/NO expression, mitochondrial membrane potential (MMP), as well as CBS expression and activity. It was found that both high glucose and MGO decreased cell viability and co-treatment with the two induced a more serious injury in RSC96 cells. Therefore, the exposure to HG&MG was used in the present study. The exposure to HG&MG markedly induced iNOS expression, NO and O2(-) generation, as well as MMP loss. In addition, the exposure to HG&MG depressed CBS expression and activity in RSC96 cells. However, the preconditioning with CCT significantly antagonized HG&MG-induced cell injury including the decreased viability, iNOS overexpression, NO and O2(-) accumulation, as well as MMP loss. CCT also partially restored the decreased CBS expression and activity triggered by HG&MG, while the inhibition of CBS with hydroxylamine attenuated CCT-mediated neuroprotection. Moreover, the exogenous donation of H2S produced similar cellular protective effects to CCT. The data indicate that the supplementation of vitamin D prevents HG&MG-induced peripheral nerve injury involving the restoration of endogenous H2S system, which may provide a

  8. Biocompatibility of Schwann Cells with PDLLA/CS/CHS Self-assembled Composite Materials%雪旺细胞与PDLLA/CS/CHS自组装复合材料生物相容性研究

    Institute of Scientific and Technical Information of China (English)

    杨利剑; 梅玉峰; 徐海星

    2011-01-01

    Objective To investigate the biocompatibility of self-cultured Schwann cells with polylactic acid/chondroitin sulfate/chitosan(PDLLA/CS/CHS) composite material with good biodegradability, and evaluate the possibility of the PDLLA/CS/CHS material applied to the repair of peripheral nerve. Methods By using pairs of differential adhesion,Schwann cells were cultured and purified. The growth curve of Schwann cells was drawn,and their phenotypes were examined by using HF staining and immunohistochemical staining. The purified Schwann cells were seeded in the PDLLA/CS/CHS composite materials and the biocompatibility was studied by using MTT method and environmental scanning electron microscopy. Results The growth platform period of Schwann cells was 1 day,the logarithmic period was 5-7 days, and the doubling time was 5 days with the purity of more than 90 %. MTT assay revealed that at 0,2nd,4th day after inoculation.The absorbance(A)values in PDLLA group,CHS group,and PDLLA/CS/CHS group were lower than in control group. At the 7th and lOth day, the A values in PDLLA and CHS groups were also lower than in control group,and those in PDLLA/CS/CHS group were higher than in control group with no significant difference(P>0. 05). But there was significant difference in the A values between PDLLA/CS/CHS group and PDLLA group(P<0. 05). Conclusion PDLLA/CS/CHS composite is biological materials with ideal biocompatibility and good material-cell interface.and facilitates the adhesion,growth and proliferation of Schwann cells.%目的 利用自行培养的雪旺细胞(SCs)与具有良好可生物降解性的高分子聚乳酸/硫酸软骨素/壳聚糖(PDLLA/CS/CHS)复合材料进行生物相容性研究,评价该材料应用于周围神经修复的可能性.方法 利用双差速贴壁法进行SCs的培养与纯化,并观察其生长曲线,苏木精-伊红染色和免疫组织化学染色观察细胞表征;将纯化后的SCs接种在PDLLA/CS/CHS复合材料上进行材料生物

  9. Microprocessor complex subunit DiGeorge syndrome critical region gene 8 (Dgcr8) is required for schwann cell myelination and myelin maintenance.

    Science.gov (United States)

    Lin, Hsin-Pin; Oksuz, Idil; Hurley, Edward; Wrabetz, Lawrence; Awatramani, Rajeshwar

    2015-10-02

    We investigated the role of a key component of the Microprocessor complex, DGCR8, in the regulation of myelin formation and maintenance. We found that conditionally ablating Dgcr8 in Schwann cells (SCs) during development results in an arrest of SC differentiation. Dgcr8 conditional knock-out (cKO) SCs fail to form 1:1 relationships with axons or, having achieved this, fail to form myelin sheaths. The expression of genes normally found in immature SCs, such as sex-determining region Y-box 2 (Sox2), is increased in Dgcr8 cKO SCs, whereas the expression of myelin-related genes, including the master regulatory transcription factor early growth response 2 (Egr2), is decreased. Additionally, expression of a novel gene expression program involving sonic hedgehog (Shh), activated de novo in injured nerves, is elevated in Dgcr8 cKOs but not in Egr2 null mice, a model of SC differentiation arrest, suggesting that the injury-related gene expression program in Dgcr8 cKOs cannot be attributed to differentiation arrest. Inducible ablation of Dgcr8 in adult SCs results in gene expression changes similar to those found in cKOs, including an increase in the expression of Sox2 and Shh. Analyses of these nerves mainly reveal normal myelin thickness and axon size distribution but some dedifferentiated SCs and increased macrophage infiltration. Together our data suggest that Dgcr8 is responsible for modulation of gene expression programs underlying myelin formation and maintenance as well as suppression of an injury-related gene expression program.

  10. Nerve growth factor blocks the glucose-induced down-regulation of caveolin-1 expression in Schwann cells via p75 neurotrophin receptor signaling.

    Science.gov (United States)

    Tan, Wenbin; Rouen, Shefali; Barkus, Kristin M; Dremina, Yelena S; Hui, Dongwei; Christianson, Julie A; Wright, Douglas E; Yoon, Sung Ok; Dobrowsky, Rick T

    2003-06-20

    Altered neurotrophism in diabetic peripheral neuropathy (DPN) is associated in part with substantial degenerative changes in Schwann cells (SCs) and an increased expression of the p75 neurotrophin receptor (p75NTR). Caveolin-1 (Cav-1) is highly expressed in adult SCs, and changes in its expression can regulate signaling through Erb B2, a co-receptor that mediates the effects of neuregulins in promoting SC growth and differentiation. We examined the hypothesis that hyperglycemia-induced changes in Cav-1 expression and p75NTR signaling may contribute to altered neurotrophism in DPN by modulating SC responses to neuregulins. In an animal model of type 1 diabetes, hyperglycemia induced a progressive decrease of Cav-1 in SCs of sciatic nerve that was reversed by insulin therapy. Treatment of primary neonatal SCs with 20-30 mm d-glucose, but not l-glucose, was sufficient to inhibit transcription from the Cav-1 promoter and decrease Cav-1 mRNA and protein expression. Hyperglycemia prolonged the kinetics of Erb B2 phosphorylation and significantly enhanced the mitogenic response of SCs to neuregulin1-beta1, and this effect was mimicked by the forced down-regulation of Cav-1. Intriguingly, nerve growth factor antagonized the enhanced mitogenic response of SCs to neuregulin1-beta1 and inhibited the glucose-induced down-regulation of Cav-1 transcription, mRNA, and protein expression through p75NTR-dependent activation of JNK. Our data suggest that Cav-1 down-regulation may contribute to altered neurotrophism in DPN by enhancing the response of SCs to neuregulins and that p75NTR-mediated JNK activation may provide a mechanism for the neurotrophic modulation of hyperglycemic stress.

  11. Immunohistochemical, ultrastructural and functional analysis of axonal regeneration through peripheral nerve grafts containing Schwann cells expressing BDNF, CNTF or NT3.

    Directory of Open Access Journals (Sweden)

    Maria João Godinho

    Full Text Available We used morphological, immunohistochemical and functional assessments to determine the impact of genetically-modified peripheral nerve (PN grafts on axonal regeneration after injury. Grafts were assembled from acellular nerve sheaths repopulated ex vivo with Schwann cells (SCs modified to express brain-derived neurotrophic factor (BDNF, a secretable form of ciliary neurotrophic factor (CNTF, or neurotrophin-3 (NT3. Grafts were used to repair unilateral 1 cm defects in rat peroneal nerves and 10 weeks later outcomes were compared to normal nerves and various controls: autografts, acellular grafts and grafts with unmodified SCs. The number of regenerated βIII-Tubulin positive axons was similar in all grafts with the exception of CNTF, which contained the fewest immunostained axons. There were significantly lower fiber counts in acellular, untransduced SC and NT3 groups using a PanNF antibody, suggesting a paucity of large caliber axons. In addition, NT3 grafts contained the greatest number of sensory fibres, identified with either IB4 or CGRP markers. Examination of semi- and ultra-thin sections revealed heterogeneous graft morphologies, particularly in BDNF and NT3 grafts in which the fascicular organization was pronounced. Unmyelinated axons were loosely organized in numerous Remak bundles in NT3 grafts, while the BDNF graft group displayed the lowest ratio of umyelinated to myelinated axons. Gait analysis revealed that stance width was increased in rats with CNTF and NT3 grafts, and step length involving the injured left hindlimb was significantly greater in NT3 grafted rats, suggesting enhanced sensory sensitivity in these animals. In summary, the selective expression of BDNF, CNTF or NT3 by genetically modified SCs had differential effects on PN graft morphology, the number and type of regenerating axons, myelination, and locomotor function.

  12. Transplantation of Schwann cells and olfactory ensheathing glia after spinal cord injury: does pretreatment with methylprednisolone and interleukin-10 enhance recovery?

    Science.gov (United States)

    Pearse, Damien Daniel; Marcillo, Alexander Eduardo; Oudega, Martin; Lynch, Michael Paul; Wood, Patrick McGhee; Bunge, Mary Bartlett

    2004-09-01

    Methylprednisolone (MP) and interleukin-10 (IL-10) are tissue protective acutely after spinal cord injury (SCI); their combination offers additive protection (Takami et al., 2002a). Our study examined if acute administration of MP (30 mg/kg i.v. at 5 min, and 2 and 4 h after injury) and IL-10 (30 mg/kg i.p. at 30 min after injury) increases the efficacy of Schwann cell (SC) or SC plus olfactory ensheathing glia (SC/OEG) grafts transplanted into rat thoracic cord 1 week after contusive injury. Efficacy was determined by histology, anterograde and retrograde tracing, immunohistochemistry for gliosis and specific nerve fibers, and several behavioral tests. Administration of MP/IL-10 or SC or SC/OEG transplantation significantly increased the total volume of a 9-mm segment of cord encompassing the injury site at 12 weeks. The combination of either SC or SC/OEG transplantation with MP/IL-10 most significantly reduced cavitation. The individual treatments all significantly increased the volume of normal-appearing tissue compared to injury-only controls; however, significant decreases in the volume of normal-appearing tissue were seen when MP/IL-10 and cell grafts were combined compared to MP/IL-10 alone. SC/OEG grafts were effective in promoting serotonergic fiber growth into the graft and led to more reticulospinal fibers caudal to the graft; combination with MP/IL-10 did not further increase fiber number. Only the combination of MP/IL-10 with SC/OEG transplants significantly improved gross locomotor performance (BBB scores) over injury-only controls. MP/IL-10 given prior to SC-only transplants, however, worsened behavioral outcome. Because beneficial effects of MP/IL-10 were not always additive when combined with cell transplantation, we need to understand (1) how tissue protective agents may transform the milieu of the injured spinal cord to the benefit or detriment of later transplanted cells and (2) whether neuroprotectants need to be re-administered at the time of

  13. NF1 deficiency causes Bcl-xL upregulation in Schwann cells derived from neurofibromatosis type 1-associated malignant peripheral nerve sheath tumors.

    Science.gov (United States)

    Park, Ho-Jin; Lee, Su-Jin; Sohn, Young Bae; Jin, Hyun-Seok; Han, Jae-Ho; Kim, Young-Bae; Yim, Hyunee; Jeong, Seon-Yong

    2013-02-01

    Since the bi-allelic inactivation of both neurofibromin 1 (NF1) gene alleles (NF1(-/-)) in Schwann cells (SCs) is common in both benign plexiform neurofibromas (PNs) and malignant peripheral nerve sheath tumors (MPNSTs) in patients with neurofibromatosis type 1 (NF1), other genetic alterations in SCs may be required for tumor progression of PNs to MPNSTs. We found that the anti-apoptotic Bcl-xL protein is upregulated in MPNST tissues compared to PN tissues from patients with NF1 by immunohistological staining. In addition, we investigated whether Bcl-xL is upregulated in SCs derived from MPNSTs and found a significantly higher Bcl-xL expression level in sNF96.2 MPNST-derived SCs compared to normal human SCs (HSCs). We also discovered that the increased Bcl-xL expression caused an increase in drug resistance to doxorubicin in MPNST-derived SCs. Manipulation of NF1 gene expression levels by treatment with small interfering RNA (siRNA) and overexpression of the neurofibromin GAP-related domain (NF1-GRD) demonstrated that upregulated Bcl-xL expression in MPNST-derived SCs was caused by NF1 deficiency. Treatment with the Erk1/2 inhibitor, PD98059, resulted in a slight increase in Bcl-xL levels in neurofibromin-depleted normal HSCs, indicating that Bcl-xL upregulation in MPNST-derived SCs is mediated by activated Erk1/2, which is a Ras downstream protein regulated by neurofibromin. As the reduction of Bcl-xL expression restored sensitivity to doxorubicin-induced apoptosis in sNF96.2 cells, we examined the effect of the small molecule Bcl-xL inhibitor ABT-737 on sNF96.2 cells. A very low dose of ABT-737 combined with doxorubicin synergistically enhanced sensitivity to doxorubicin-induced apoptosis in sNF96.2 cells, suggesting that ABT-737 and doxorubicin may be a good combination to effectively treat NF1-associated MPNSTs with minimal side-effects. Collectively, our results suggest that upregulation of Bcl-xL in MPNST-derived SCs may be caused by the NF1 deficiency

  14. The insulin-like growth factors I and II stimulate proliferation of different types of Schwann cells

    DEFF Research Database (Denmark)

    Sondell, M; Svenningsen, Åsa Fex; Kanje, M

    1997-01-01

    A combination of immunocytochemistry for glial specific antigens and bromodeoxyuridine (BrdU) and teasing was used to identify proliferating cells in cultured rat sciatic nerve segments. The nerve segments were exposed to insulin, or the insulin-like growth factors IGF-I and IGF-II. Teasing...

  15. A study of sensory and motor Schwann cell culture in vitro%感觉性和运动性神经膜细胞的培养研究

    Institute of Scientific and Technical Information of China (English)

    秦煜; 顾立强; 裴国献; 吴岚晓

    2003-01-01

    目的对感觉性和运动性神经来源的神经膜细胞进行培养和鉴定,并通过神经生长因子( NGF)的表达间接地研究两种细胞的差别,探讨对神经特异性再生的影响.方法立体显微镜下对 SD乳鼠后根神经和股神经运动支进行取材,经 2.5 g/L胰蛋白酶+ 0.3 g/L IV型胶原酶联合消化,用高糖型 DMEM/F12 (含 100 g/L CS) 对感觉神经源性和运动神经源性的神经膜细胞进行培养,并经抗 S100荧光组织化学染色鉴定.双抗体夹心间接 ELISA法测量两种神经膜细胞培养基中 NGF的表达.结果培养的两种神经膜细胞经荧光染色证明均为神经膜细胞,光镜观察并手工计数显示两种细胞纯度均超过 95%,未见形态学差异,但 NGF的表达量和表达模式差异均有显著性意义 (F=45.3681, P=0.000).结论本实验方法可以获得高纯度的感觉性和运动性神经源性神经膜细胞,两者的生物学功能有差异.%Aim To establish the culture method of sensory and motor Schwann cells for the use of nerve tissue engineering and study their biological differences.Methods Sensory and motor Schwann cells were cultured respectively from dorsal root nerves and femoral nerve's motor rami of 5- day old SD rat.The cultured Schwann cells were identified by anti- S100 immuno- fluorescent immunohistochemical staining,and the NGF expressions of two kinds of cells in the culture media were measured by Sandwich ELISA. Results Both kinds of cells were proved to be Schwann cells.No obvious difference was observed at morphology under light microscope, but their NGF expressions were different in both quantity and pattern (F=45.3681, P=0.000).Conclusion High purity of sensory and motor Schwann cells needed by nerve tissue engineering can be prepared by this method, and there is biological difference between them.

  16. High glucose upregulates CYP24A1 expression which attenuates the ability of 1,25(OH)2D3 to increase NGF secretion in a rat Schwann cell line RSC96.

    Science.gov (United States)

    Zhou, Yi-Kun; Liang, Zhi; Guo, Yan; Zhang, Hua-Tang; Wang, Kun-Hua

    2015-03-15

    Vitamin D deficiency or insufficiency is an independent risk factor for diabetic peripheral neuropathy (DPN), but the relationship between 1,25(OH)2D3 and DPN remains unknown. We found that 1,25(OH)2D3 stimulated the secretion of nerve growth factor (NGF) in rat Schwann cell line RSC96, but ability of 1,25(OH)2D3 to increase NGF protein was impaired under high glucose conditions. High glucose upregulated the expression of CYP24A1 protein, which catalyzes the conversion of 1,25(OH)2D3 into inactive products, further impairing the ability of 1,25(OH)2D3 to upregulate NGF secretion in Schwann cells. Inhibition of CYP24A1 protein expression ameliorated the secretion of NGF in response to 1,25(OH)2D3. The findings of this study suggest that CYP24A1 protein plays an important role in the relationship between DPN and 1,25(OH)2D3.

  17. First human experience with autologous Schwann cells to supplement sciatic nerve repair: report of 2 cases with long-term follow-up.

    Science.gov (United States)

    Gersey, Zachary C; Burks, S Shelby; Anderson, Kim D; Dididze, Marine; Khan, Aisha; Dietrich, W Dalton; Levi, Allan D

    2017-03-01

    OBJECTIVE Long-segment injuries to large peripheral nerves present a challenge to surgeons because insufficient donor tissue limits repair. Multiple supplemental approaches have been investigated, including the use of Schwann cells (SCs). The authors present the first 2 cases using autologous SCs to supplement a peripheral nerve graft repair in humans with long-term follow-up data. METHODS Two patients were enrolled in an FDA-approved trial to assess the safety of using expanded populations of autologous SCs to supplement the repair of long-segment injuries to the sciatic nerve. The mechanism of injury included a boat propeller and a gunshot wound. The SCs were obtained from both the sural nerve and damaged sciatic nerve stump. The SCs were expanded and purified in culture by using heregulin β1 and forskolin. Repair was performed with sural nerve grafts, SCs in suspension, and a Duragen graft to house the construct. Follow-up was 36 and 12 months for the patients in Cases 1 and 2, respectively. RESULTS The patient in Case 1 had a boat propeller injury with complete transection of both sciatic divisions at midthigh. The graft length was approximately 7.5 cm. In the postoperative period the patient regained motor function (Medical Research Council [MRC] Grade 5/5) in the tibial distribution, with partial function in peroneal distribution (MRC Grade 2/5 on dorsiflexion). Partial return of sensory function was also achieved, and neuropathic pain was completely resolved. The patient in Case 2 sustained a gunshot wound to the leg, with partial disruption of the tibial division of the sciatic nerve at the midthigh. The graft length was 5 cm. Postoperatively the patient regained complete motor function of the tibial nerve, with partial return of sensation. Long-term follow-up with both MRI and ultrasound demonstrated nerve graft continuity and the absence of tumor formation at the repair site. CONCLUSIONS Presented here are the first 2 cases in which autologous SCs were

  18. The extracellular signal-regulated kinase was promoted by Pyrroloquinoline Quinine in cultured Schwann cells%MEK/ERK信号通路在吡咯喹啉醌促雪旺细胞增殖中的作用

    Institute of Scientific and Technical Information of China (English)

    贺斌; 刘世清; 李皓桓

    2010-01-01

    目的 探讨MEK/ERK信号通路在吡咯喹啉醌促雪旺细胞增殖过程中的作用. 方法 体外培养雪旺细胞,S-100免疫荧光鉴定;Western blot检测MEK下游因子ERK1/2磷酸化激活形式(p-ERK1/2)的表达;MEK抑制剂(PD98059)阻断该通路后检测p-ERK1/2的表达;MTT法检测经PD98059阻断MEK通路后雪旺细胞的增殖情况. 结果 吡咯喹啉醌可激活雪旺细胞内MEK/ERK信号通路,在加入吡咯喹啉醌1 h后p-ERK1/2表达最高;吡咯喹啉醌在1~500 nmol/L范围内可使p-ERK1/2表达增加,1 000 nmol/L时与对照组比较差异无统计学意义,10 000 nmol/L时则表现为抑制作用(P<0.05);经PD98059阻断MEK通路后p-ERK1/2的上调效应消失(P<0.05).而且加入PD98059阻断MEK通路后吡咯喹啉醌对雪旺细胞的促增殖效果减弱. 结论 吡咯喹啉醌可激活雪旺细胞MEK/ERK信号通路,且该通路在吡咯喹啉醌促雪旺细胞增殖过程中发挥作用.%Objective To investigate the effect of mitogen-activated protein kinase(MEK)kinase cascade,extracellular signal-regulated kinase(ERK1/2)signal pathway on Schwann cells proliferation promoted by Pyrroloquinoline Quinine(PQQ)and its molecular mechanisms. Methods Schwann cells were cultured and purified in vitro.The purity was identified by S-100.Different time and concentration of PQQ was added into culture medium.The expression of ERK1/2 and phosphorylated-ERK1/2 was detected by western blot.The expression of p-ERK1/2 after blocking of MEK signal pathway by specific inhibitor PD98059 was detected by western blot. Results Morphological change was observed in PQQ treated Schwann cells.1 ~ 500 nmol/L PQQ could up-regulate the expression of p-ERK1/2,and 1 000 nmol/Lhad no effects,while 10 000 nmol/L exhibited inhibitory effect(P<0.05).p-ERKI/2 increased to peak 1 h after PQQ added,and this up-regulation of p-ERKI/2 was inhibited by PD98059(P<0.05). Conclusions PQQ could affect morphology of Schwann cells and activation of ERKI/2

  19. 腺样囊性癌组织中肌上皮细胞标记物α-SMA 与雪旺氏细胞标志物 Leu -7的共同表达%Coepression of myoepithelial cell marker α-SMA and Schwann cell marker Leu -7 insalivary adenoid cystic carcinoma

    Institute of Scientific and Technical Information of China (English)

    谢耕耘; 杨建智

    2015-01-01

    目的:检测肿瘤性肌上皮细胞标记物α-SMA 与雪旺细胞标记物 Leu -7在 ACC 中的表达。方法:免疫组织化学法检测 ACC 与粘液表皮样癌细胞中肌上皮细胞标记物α-SMA 蛋白与雪旺细胞标记物 Leu -7蛋白在病理切片中的表达。结果:Leu -7蛋白及 a -SMA 蛋白在 ACC 中存在共表达现象,提示二者分布在同种细胞中。结论:在 ACC 中 Leu -7蛋白及 a -SMA 蛋白存在共表达现象。%objective:Detection expression of myoepithelial cell marker α-SMA and the Schwann cell marker Leu -7 in the ACC.Methods:Immunohis-tochemical Detection expression of the myoepithelial cell marker α-SMA protein and Schwann cell marker Leu -7 protein in ACC and mucoepidermoid carcino-ma.Result:In the ACC both were observed phenomenon of tumor cells perineural invasion.Conclusion:ACC organizations has existed Schwann cell differenti-ation of the tumor cells.

  20. 双重消减纯化体外培养许旺细胞%In vitro purification of Schwann cells with double negative selection

    Institute of Scientific and Technical Information of China (English)

    史金凤; 雷雳; 夏寅

    2007-01-01

    BACKGROUND: Although cultured technique and purified method of Schwann cells (SCs) are changed successively,purity is still limited. Whether double negative selections can culture high-purified SCs still needs a further study.OBJECTIVE: To investigate the effects of double negative selections on growth and purity of SCs.DESIGN: Controlled animal study.SETTING: Department of Otolaryngology Head and Neck Surgery, Beijing Tongren Hospital, Capital Medical University,and the Beijing Institution of Otolaryngology.MATERIALS: The experiment was carried out in the Department of Otolaryngology Head and Neck Surgery, Beijing Tongren Hospital, Capital Medical University and the Beijing Institution of Otolaryngology between May 2006 and July 2006. Twenty new-born Wistar rats of 3 days (without gender limitation) were provided by the Experimental Animal Center of the Chinese Medical Academy.METHODS: The sciatic nerves of rats were digested by 0.2% collagenase. ① Grouping: All the rats were divided into 4 groups with 5 each. The experimental group was depurated by differential adhesion and Ara-c for 30 minutes. SCs in the control group 1 and 2 were managed by differential adhesion and Ara-c for 30 minutes, respectively. Cells in the control group 3 were not purified. ② Evaluation: The cell growth was observed under invert microscope; growth curves were measured with MTT method in the experimental group and control group 3 to observe cell proliferation. In addition, the SCs were identified by immunocytochemistry; the culture purity was calculated (ratio of S100 positive cells in each sight).MAIN OUTCOME MEASURES: ① Growth of SCs; ② immunocytochemistry stain of SCs; ③ growth curve of SCs; ④ purity of SCs.RESULTS: ① Growth of SCs: At 5 days after incubation, the SCs proliferated well. SCs were spindle, bipolar and sometimes tripolar, with obvious nuclei and a little cytoplasm. There was more fibroblast cell in the group 3 than that in experimental group. ② Growth

  1. A new sodium channel alpha-subunit gene (Scn9a) from Schwann cells maps to the Scn1a, Scn2a, Scn3a cluster of mouse chromosome 2.

    Science.gov (United States)

    Beckers, M C; Ernst, E; Belcher, S; Howe, J; Levenson, R; Gros, P

    1996-08-15

    We have used a total of 27 AXB/BXA recombinant inbred mouse strains to determine the chromosomal location of a newly identified gene encoding an alpha-subunit isoform of the sodium channel from Schwann cells, Scn9a. Linkage analysis established that Scn9a mapped to the proximal segment of mouse chromosome 2. The segregation of restriction fragment length polymorphisms in 145 progeny from a Mus spretus x C57BL/6J backcross indicates that Scn9a is very tightly linked to Scn1a (gene encoding the type I sodium channel alpha-subunit of the brain) and forms part of a cluster of four Scna genes located on mouse chromosome 2.

  2. A new sodium channel {alpha}-subunit gene (Scn9a) from Schwann cells maps to the Scn1a, Scn2a, Scn3a cluster of mouse chromosome 2

    Energy Technology Data Exchange (ETDEWEB)

    Beckers, M.C.; Ernst, E.; Gros, P. [McGill Univ., Montreal (Canada)

    1996-08-15

    We have used a total of 27 AXB/BXA recombinant inbred mouse strains to determine the chromosomal location of a newly identified gene encoding an {alpha}-subunit isoform of the sodium channel from Schwann cells, Scn9a. Linkage analysis established that Scn9a mapped to the proximal segment of mouse chromosome 2. The segregation of restriction fragment length polymorphisms in 145 progeny from a Mus spretus x C57BL/6J backcross indicates that Scn9a is very tightly linked to Scn1a (gene encoding the type I sodium channel {alpha}-subunit of the brain) and forms part of a cluster of four Scna genes located on mouse chromosome 2. 17 refs., 1 fig., 3 tabs.

  3. Co-transplantation of autologous bone marrow mesenchymal stem cells and Schwann cells through cerebral spinal fluid for the treatment of patients with chronic spinal cord injury: safety and possible outcome.

    Science.gov (United States)

    Oraee-Yazdani, S; Hafizi, M; Atashi, A; Ashrafi, F; Seddighi, A-S; Hashemi, S M; Seddighi, A; Soleimani, M; Zali, A

    2016-02-01

    This is a clinical trial (phase 1). The objective of this study was to asses the safety and feasibility of bone marrow mesenchymal stem cell (MSC) and Schwann cell (SC) co-injection through cerebral spinal fluid (CSF) for the treatment of patients with chronic spinal cord injury. Six subjects with complete spinal cord injury due to trauma according to International Standard of Neurological Classification for Spinal Cord Injury (ISNCSCI) developed by the American Spinal Injury Association were enrolled. They received autologous co-transplantation of MSC and SC through lumbar puncture. Neurological status of the patients was determined by ISNCSCI, as well as by assessment of functional status by Spinal Cord Independent Measure. Before and after cell transplantation, magnetic resonance imaging (MRI) was performed for all the patients. Before the procedure, all the patients underwent electromyography, urodynamic study (UDS) and MRI tractograghy. After transplantation, these assessments were performed in special cases when the patients reported any changes in motor function or any changes in urinary sensation. Over the mean 30 months of follow-up, the radiological findings were unchanged without any evidence of neoplastic tissue overgrowth. American Spinal Injury Association class in one patient was changed from A to B, in addition to the improvement in indexes of UDS, especially bladder compliance, which was congruous with axonal regeneration detected in MRI tractography. No motor score improvement was observed among the patients. No adverse findings were detected at a mean of 30 months after autologous transplantation of the combination of MSCs and SCs through CSF. It may suggest the safety of this combination of cells for spinal cord regeneration.

  4. Human primordial germ cells migrate along nerve fibers and Schwann cells from the dorsal hind gut mesentery to the gonadal ridge

    DEFF Research Database (Denmark)

    Møllgård, Kjeld; Jespersen, Åse; Lutterodt, Melissa Catherine

    2010-01-01

    The aim of this study was to investigate the spatiotemporal development of autonomic nerve fibers and primordial germ cells (PGCs) along their migratory route from the dorsal mesentery to the gonadal ridges in human embryos using immunohistochemical markers and electron microscopy. Autonomic nerve...

  5. Isolation and culture of neural stem cells derived from rat spinal cord and their differentiation into Schwann cells in vitro%脊髓来源神经干细胞分离培养及向雪旺氏细胞的诱导分化

    Institute of Scientific and Technical Information of China (English)

    赵信德; 柯以铨; 姜晓丹; 闫中杰; 李西锋

    2010-01-01

    目的 探讨新生大鼠脊髓来源神经干细胞(NSCs)的分离培养及在体外一定条件下向周围神经雪旺氏细胞分化的可行性. 方法 分离新生大鼠的脊髓组织,在含有B27(终浓度1%)、碱性成纤维细胞生长因子(bFGF)和表皮生长因子(EGF)(终浓度均为20 μg/L)培养基中分离培养出NSCs.用复合诱导因子(10%FBS+5 μmol/L血小板凝集抑制剂+10 ng/mL bFGF+5 ng/mE血小板源性生长因子)在体外诱导NSCs分化为雪旺氏细胞.免疫荧光细胞化学方法[一抗为p75、S-100、神经胶质纤维酸性蛋白(GFAP)]鉴定体外诱导分化结果.结果 培养的新生大鼠脊髓组织细胞nestin染色表达阳性;分离培养的大鼠脊髓来源NSCs经诱导分化后形态类似雪旺氏细胞,免疫荧光细胞化学方法显示诱导后细胞表达雪旺氏细胞的表面标志,GFAP、S-100和P75表达阳性.结论 新生大鼠脊髓来源NSCs可以在体外诱导分化为雪旺氏细胞.%Objective To study whether peripheral nerve Schwann cells can be derived from neural stem cells obtained from neonatal rat spinal cord under certain condition in vitro. Methods Cells of neonatal rat spinal cord were isolated and maintained in conditioned medium that was supplemented with B27(final concentration of 1%),recombinant hunman basic-fibroblast growth factor (bFGF)and epidermal growth factor(EGF,final concentration of 20 μg/L)to induce the neural stem cells.Schwann cells were induced subsequently by compound induce factors(5 mL forskolin+10 ng/mL basic-FGF+5 ng/mL PDGF-AA+10%FBS).Immunohistochemical staining(antibody:p75,S-100 and GFAP) was performed to indentify the induction of Schwann cells. Results Cells isolated from neonatal rat spinal cord showed positive expression of nestin;neural stem cells induced from these cells can subsequently differentiate into morphologically Schwann cell-like cells in the supplements of compound factors.Positive expressions of Schwann cells markers(GFAP,S-100 and P

  6. The roles of PI3K/Akt pathway in proliferation of Schwann cells promoted by Pyrroloquinoline Quinine%PI3K/Akt信号通路在吡咯喹啉醌促雪旺细胞增殖中的作用

    Institute of Scientific and Technical Information of China (English)

    贺斌; 刘世清; 李皓桓

    2010-01-01

    目的 探讨磷脂酰肌醇-3激酶/蛋白激酶B(phosphoinositide-3 kinase/Akt,PI3K/Akt)信号通路在吡咯喹啉醌促雪旺细胞增殖过程中的作用.方法 体外分离培养雪旺细胞,S-100免疫荧光鉴定;Western blot检测PI3K下游因子Akt磷酸化激活形式(p-Akt)的表达,并通过PI3K激酶抑制剂(wortmannin)阻断该通路后p-Akt的表达情况.结果 毗咯喹啉醌可使雪旺细胞发生形态学变化,加入吡咯喹啉醌后30 min即可检测到p-Akt的表达,4 h达高峰,12 h基本无表达;吡咯喹啉醌在1~100 nmol/L范围内可使p-Akt表达增加;加入wortmannin阻断PI3K后p-Akt上调表达消失(P<0.05).结论 吡咯喹啉醌可使雪旺细胞发生形态学变化,PI3K/Akt信号通路在吡咯喹啉醌促雪旺细胞增殖过程中发挥重要作用.%Objective To investigate the roles of PI3K/Akt signal pathway in Schwann cells proliferation promoted by pyrroloquinoline quinine (PQQ). Methods Schwann cells were cultured and purified in vitro. The purity was identified by immunofluorescence of S-100; the expression of Akt and phosphorylated-Akt(p-Akt) were detected by western blot, and the expression of p-Akt after blocking the PI3K signal transduction pathway by PI3K inhibitor wortmannin was detected by western blot. Results Morphological change was observed in PQQ-treated Schwann cells, p-Akt was detected 30min after PQQ treated, reached the peak at 4h, and disappeared 12 h later. 1-100 nmol/L PQQ could up-regulate the expression of p-Akt; this up-regulated expression of p-Akt was inhibited by wortmannin (P < 0.05).Conclusions PQQ could affect morphology of Schwann cells and activation of Akt. It indicates that PI3K/Akt signal pathway might be involved in Schwann cells proliferation promoted by PQQ.

  7. 坐骨神经瓦勒变性大鼠许旺细胞生物学特性及分泌功能变化%Effects of Wallerian degeneration on biological characteristics and secretory function of Schwann cells in rats with sciatic nerve injury

    Institute of Scientific and Technical Information of China (English)

    李月珍; 武庚; 武杨; 金秀东; 张际绯; 赵富生

    2014-01-01

    BACKGROUND:Studies have shown that Schwann cells form a Bunger band in the basement tube and guide the extension of regenerating axons after peripheral nerve injury, but the exact mechanism remains to be explored. OBJECTIVE:To explore the effect of Wal erian degeneration on biological characteristics and secretory function of Schwann cells in rats with sciatic nerve injury. METHODS:A rat model of sciatic nerve injury was established and divided into two groups:sciatic nerve transection group and surgical control group. Schwann cells were isolated and cultured from sciatic nerve segments by one enzyme digestion. The cellmorphology was observed under light microscope and S-100 protein expression was determined by immunofluorescence staining. After subculture, the first generation of Schwann cells were chosen to draw the growth curve by the counting method within 14 days. The cellactivity was detected by MTT assay. The adhesion of Schwann cells was examined by acid phosphatase analysis and the concentration of nerve growth factor was detected by ELISA method. RESULTS AND CONCLUSION:At 14 days after primary culture, a great number of Schwann cells were observed near the edges of nerve segments in the sciatic nerve transection group, but only smal number of Schwann cells scattered around nerve segments in the control group. Schwann cells in both groups showed S-100 positive expression. At 3 days after subculture, Schwann cells reached the logarithm proliferative phase, the cellnumber and proliferation absorbance values in both groups were increased along with time extension. Furthermore, the number of Schwann cells and absorbance value in the sciatic nerve transection group were significantly higher than those of control group (P  目的:观察大鼠坐骨神经损伤后瓦勒变性对许旺细胞生物学特性及分泌功能的影响。  方法:建立大鼠坐骨神经横切模型,分为坐骨神经瓦勒变性组(坐骨神经横断

  8. 许旺细胞植入去细胞异体神经修复大鼠面神经缺损%Repair of facial nerve defects by using acellular nerve allografts implanted with Schwann cells in rats

    Institute of Scientific and Technical Information of China (English)

    朱国臣; 肖大江; 黄红宇; 袁渊; 吴四海; 赵新

    2008-01-01

    目的 观察体外分离、培养的许旺细胞对去细胞异体神经修复面神经长距离缺损的促进作用. 方法 30只大鼠随机分成A组、B组和c组(每组10只),制成而神经缺损12 mm模型,分别以去细胞异体神经联合许旺细胞、去细胞异体神经和自体神经移植修复.术后5个月分别行神经电生理、再生神经形态及数量等检测. 结果 A组神经肌肉动作电位的波幅恢复率(术侧/健侧)为(35.8±2.5)%,潜伏期恢复率(健侧/术侧)为(65.8±2.9)%;神经移植段再生轴突数为(1 570±188)个,髓鞘厚度为(0.383±0.031)μm.A组的各项指标优于B组(P0.05). 结论 许旺细胞植入去细胞异体神经可促进面神经长距离缺损的修复.%Objective To observe the effects of in vitro isolated Schwann cells co-cultured with chemically acellular nerve allografts on improving repair of large facial nerve defects. Methods A total of 30 Wistar rats were equally randomized into three groups, ie, experimental group, allograft group and autograft group. Nerve defect of 12 mm in length was made in the left inferior buccal branch of facial nerve and repaired with acellular nerve allograft implanted with Schwann cells, acellular nerve allograft and fresh tibial nerve autograft respectively. At the 5th month postoperatively, the function and morpholo-gy of the regenerated nerves were observed by electrophysiological method, methylene blue staining and transmission electron microscope. Results In experimental group, the recovery rate (operation side/normal side) of amplitude of nerve-muscle action potential was (35.8±2.5)%, the lantency recovery rate (normal side/operation side) (65.8±2.9)%, the number of the regenerated axon 1 570±188 and the myelin thickness (0.383±0.031) μm. The results in the experimental group were significantly supe-rior to those in the acellular nerve allograft group (P 0.05). Conclusion Transplantation of Schwarm cells in acellular nerve allograft can im

  9. Co-transplantation of neural stem cells and Schwann cells in rat semi-transected spinal cord%神经干细胞与许旺细胞共移植于大鼠损伤脊髓

    Institute of Scientific and Technical Information of China (English)

    夏雷; 万虹; 历俊华; 郝淑煜; 杨飞; 王身国

    2008-01-01

    Objective To investigate migration,survival,differentiation of neural stem cells (NSCs) in vivo and the functional recovery of injury spinal cord when co-transplanting NSCs and Schwann cells (SCs) in rat semi-transected spinal cord. Methods NSCs labeled green fluorescence protein (GFP) and SCs were implanted into rat semi-transected spinal cord and their migration,survival,differentiation were investigated with immunofluoreseene staining. Renewal myelination was reviewed with electron microscopy (EM). Functional recovery of injury spinal cord was assessed by cortical motor evoked potentials (CMEPs) and Basso,Beattie,and Bresnahan (BBB) scores. Results When NSCs were co-grafted with SCs in rat semi-transected spinal cord,GFP positive cells in rostval,caudal and contralateral spinal cord as well as GFAP,GaLC, NSE,SYN immune response in the GFP-labeled cells could be seen under fluorescence microscope. There was remarkable increase in the number of renewal myelination under EM. The percentage of recovery and the amplitudes of CMEPs were higher than other groups,but BBB scores was not remarkable differentiation in statistical analysis. Conclusions In vivo co-transplantation of NSCs and SCs can promote migration,survival and differentiation of NSCs as well as functional recovery of injury spinal cord.%目的 观察神经干细胞与许旺细胞共移植于大鼠半横断脊髓损伤处神经干细胞的迁移、存活、分化及对损伤脊髓的修复作用.方法 绿色荧光蛋白(GFP)标记脊髓神经下细胞后与许旺细胞共移植于大鼠半横断脊髓损伤处,免疫荧光染色和电镜技术分别观察神经下细胞的迁移、存活、分化及新生的髓鞘.皮层运动诱发电位(CMEPs)及BBB评分分别检测大鼠运动功能的恢复.结果 在神经干细胞与许旺细胞共移植组,损伤脊髓的头端、尾端及对侧町见明显的GFP阳性细胞及GaLC/GFP、GFAP/GFP、NSE/GFP、SYN/GFP舣阳性细胞,电镜下新生的髓鞘最

  10. NgR基因沉默骨髓间充质干细胞/许旺细胞支架复合体的构建%Construction of the scaffold composite of bone marrow mesenchymal stem cells and Schwann cells after NgR gene silencing

    Institute of Scientific and Technical Information of China (English)

    王东; 张建军; 杨卫山

    2012-01-01

    背景:细胞联合移植、NgR基因沉默及聚乳酸-乙醇酸支架为近年来脊髓神经损伤修复的研究热点.目的:探讨NgR基因沉默的骨髓间充质干细胞/许旺细胞在聚乳酸-乙醇酸膜上生长及分化的可行性.方法:将骨髓间充质干细胞、许旺细胞分离、纯化及扩增后,经小分子干扰RNA转染以沉默NgR基因表达,用反转录-聚合酶链反应、Western blot检测两种细胞在转染前后NgR基因/蛋白的表达.在有血清的条件下,按骨髓间充质干细胞组、许旺细胞组及联合组(均以未转染细胞为对照,共6 组)分别接种到聚乳酸-乙醇酸膜上,观察各组细胞的贴附、生长、分化情况.结果与结论:转染小分子干扰RNA后,与转染前相比,实验组NgR基因和蛋白的表达量明显降低(P<0.05).经过培养,在聚乳酸-乙醇酸膜上观察与未转染组相比,NgR基因沉默各组均观测到种植细胞的大量贴附和生长.提示NgR基因沉默有促进骨髓间充质干细胞/许旺细胞贴附、生长的作用.%BACKGROUND:Combined cell transplantation, NgR gene silencing and poly-lactic acid-glycohc acid (PLGA) scaffolds have become th8 research focus of spinal cord injury repair in recent yearsOBJECTIVE:To investigate the feasibility of the growth and differentiation of bone marrow mesenchymal stem cells (BMSCs ySchwann cells in poly (lactic-co-glycohc acid) (PLGA) membrane after NgR gene silencingAfter BMSCs and Schwann cells were isolated, purified and amplified, the two kinds of cells were transfected by small interfering RNA to silence NgR gene expression The NgR gene/protein expressions in the two kinds of cells before and after transfection were detected by reverse transcnption-PCR and Western blot methods Under serum conditions the cells were divided into BMSCs group Schwann cells group and combination group (all untransfected cells as controls, six groups in total) Then, the cells were inoculated onto the PLGA membrane, and

  11. Activation of MAPK overrides the termination of myelin growth and replaces Nrg1/ErbB3 signals during Schwann cell development and myelination

    NARCIS (Netherlands)

    M.E. Sheean (Maria); E. McShane (Erik); C. Cheret (Cyril); J. Walcher (Jan); T. Müller (Thomas); A. Wulf-Goldenberg (Annika); S. Hoelper (Soraya); A.N. Garratt (Alistair); M. Krüger (Markus); K. Rajewsky (Klaus); D.N. Meijer (Dies); W. Birchmeier (Walter); G.R. Lewin (Gary); M. Selbach (Matthias); C. Birchmeier (Carmen)

    2014-01-01

    textabstractMyelination depends on the synthesis of large amounts of myelin transcripts and proteins and is controlled by Nrg1/ErbB/Shp2 signaling. We developed a novel pulse labeling strategy based on stable isotope labeling with amino acids in cell culture (SILAC) to measure the dynamics of myelin

  12. 乳香提取物对大鼠雪旺细胞增殖和相关蛋白表达的影响%Effects of frankincense extract on proliferation and expression of related proteins of rat Schwann cells

    Institute of Scientific and Technical Information of China (English)

    陆子音; 姜晓文; 姜龙; 康欣; 于文会

    2013-01-01

    Through studying the influence of frankincense extract on repairing peripheral nerve injury,thus offering the theoretical foundation for wound healing of herbs,rat Schwann cells(SCs) were subcultured as a experimental model,and it was cultured with different concentrations of the extract.In the range of safe concentration,SCs were randomly divided into control group and drug group,and different concentration of the extract was added to intervene cell growth.The cell proliferation was observed at hour 12,24,48,72 and 96 post-cultivation.Flow cytometry method was applied to test cell cycle and the percent content of DNA.ELISA kit was used to detect the content of brain derived neurotrophic factor(BDNF),neural cell adhesive molecule(NCAM) and proliferative cell nucleus antigen(PCNA).Results showed that the safe concentration of the extract was from 62.5 mg/L to 8 000 mg/L.Compared with the control group,cell proliferation at the concentration of 125,250 and 500 mg/L increased significantly(P<0.05).The results of MTT colorimetric test and flow cytometry method showed that the extract could significantly promoted cell proliferation at 125 mg/L(P<0.01).It suggested that the extract at certain concentration was effective on inducing the proliferation of SCs,and the best concentration was 125 mg/L.At the same time,it could up-regulate the expression of BDNF,NCAM and PCNA of SCs cultured in vitro.%通过研究乳香提取物对周围神经损伤的修复作用,为中药治疗创伤提供理论依据.将大鼠雪旺细胞株进行传代培养,通过MTT法筛选出乳香提取物干预大鼠雪旺细胞生长的安全浓度.在安全浓度范围内,将雪旺细胞随机分为对照组和药物组,用不同浓度的乳香提取物干预细胞生长,培养后第12、24、48、72和96小时,观察其对细胞增殖的影响;用流式细胞术检测细胞周期及DNA含量百分率;用ELISA试剂盒检测雪旺细胞分泌脑源性神经营养因子(BDNF)、神经细胞黏

  13. The effect of microgene pSVPoMcat to modify Schwann cell on GAP- 43 expression after spinal cord injury in adult rats%微基因修饰雪旺氏细胞移植对大鼠脊髓损伤后GAP-43表达的影响

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    陈礼刚; 高立达; 毛伯镛; 杨立斌; 李开慧

    2001-01-01

    Objective To study the effect of microgene pSVPoMcat implanted to modify schwann cell on growth associated protein-43(GAP-43) expression after spinal cord injury in adult rats.Method Hemisected of the T8 segment of the spinal cord was performed for all the experiment rats.The rats were randomly divided into three groups as follows:Group A with microgene pSVPoMcat implanted to genetically modify SC;Group B with SC implanted ;Group C with hemisection of the spinal cord only.The changes of expression of GAP-43 in spinal cord were observed by immunochemistry with antibodies against GAP-43 .Simultaneous,the combined behavioral scores(CBS)was measured.Result There were not any different(P >0.05)among the three groups in first week and 12 week.There were significant diffeence(P<0.05)among three groups in 2nd,8th,and more dxpression of GAP-43 at the 2nd week in group A.The neurofunctional recovery was best in group A.Conclusion The microgene pSVPoMcat implanted to modify schwann cell can promote the expression of GAP-43 in spinal cord and functional recovery in adults rats after SCI.

  14. La célula de Schwann

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    Adriana del Pilar López Lombana

    1993-12-01

    Full Text Available La célula de Schwann que constituye la glía del SNP, además de ser el soporte estructural para los axones en dicho sistema, tiene la función de producir la mielina, una organela de gran importancia en los procesos de neuroconducción. De la integridad de esta célula dependen el desarrollo estructural y metabólico del axón, así mismo se ha reconocido desde hace varios anos el papel primordial que juega ella, en los procesos de regeneración del SPN posterior a una injuria, en cuyo caso reinician la proliferación para producir una guía de regeneración del nervio periférico. En esta revisión se contemplarán algunos de los puntos relacionados con su origen, desarrollo, estructura, relación con el axon y el tipo de patologías que pueden alterarla; igualmente se resalta la utilidad de los cultivos de celulas de Schwann para el estudio de los procesos de mielinización, desmielinización, regeneración post-traumatica y respuesta a agentes infecciosos.

  15. 同种异体神经复合体修复兔坐骨神经缺损的研究%Planting fetus rabbit schwann cells into the extracted acellular nerve graft of homogeneity in repairing rabbit sciatic nerve defect

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    杨小华; 韩金豹; 张沉冰; 田德虎; 韩久卉

    2009-01-01

    Objective To plant fetus rabbit Schwann cells that were cultured and purified in vitro into the chemically extracted acellular nerve graft of homogeneity and made it into bridging complex. Then transplant the bridging complex into the rabbit defective sciatic nerve. The experiment was designed to investigate the effect of the nerve allografts on the functional recovery and the condition of nerve regeneration. Methods 48 adult healthy New-Zealand albino rabbits,weighing 1.5-2.0 kg,were randomly divided into 2 groups with 24 rabbits each group,based on different grafts. The bridging complex were composed of Schwann cell, then transplanted it to repair defective sciatic nerve of the experiment group rabbit. The control group did not transplant Schwann cells. The sciatic nerve of lower left limb was cut in order to emerge 2cm nerves defect for each rabbit,then was transplated with different grafts. Observed the ulcers on the feet of the rabbit 4,8 and 16 weeks after operation. To observe sciatic nerve regeneration and myelination by light microscope. To observe the information of nerve regeneration and myelination and the ultrastructural change of the mitochondrion, the microtubule, the microfilament and Schwann cells by electron microscope. Make use of the analytical system on picture to treat the number of regenerated nerve fiber and the axon diameter and the thickness of myelin sheath of medullated nerve fibers,then measured the wet weight of the triceps surae. Then analyzed them in statistics. Results After operation, the immunological rejection was not found in the operating field. The experimental group was better than the control group in healing of ulcers, after 4,8,16 weeks,the number of regenerated nerve fiber and the axon diameter and the thickness of myelin sheath of medullated nervefibers (906.25 ± 30.68,1726.25 ±51. 89,2825.13 ± 22.79) , (5.35 ± 0.62,5.46 ±0.38,5.59 ±0.80), (1.65 ±0.37,1.75 ±0.41,1.83 ±0.49) (P 0.05). But after 8 and 16 weeks

  16. Influence of Advanced Glycation End Products on the Function of Schwann Cells in Vitro and Related Mechanism%糖基化终产物对雪旺细胞体外功能的影响及其机制的研究

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    张媚; 张临洪

    2013-01-01

    advanced glycation end products ( AGEs ) on rat sciatic nerve - derived Schwann cells in vitro and investigate the change of inflammatory factors in order to provide a novel therapeutic target of peripheral neuropathy in diabetes patients.Methods Primary sciatic nerve - derived Schwann cells from 3 - day neonatal SD rats were obtained, purified and then identified by immunocytochemistry staining.The Schwann cells were divided into seven groups and were treated respectively with pure culture medium ( control group ), 20 μg/ml BSA, 20 μg/ml AGEs, 50 μg/ml BSA, 50 μg/ml AGEs, 100 μg/ml BSA and 100 μg/ml AGEs respectively.Then the proliferation, migration, apoptosis and Caspase -3 mRNA of treated cells were detected.After that, the Schwann cells were divided into four groups and then were treated with pure culture medium ( control group ), 50 μg/ml BSA, 50 μg/ml AGEs and 50 μg/ml AGEs + 10 μg/ml anti - receptor of AGEs ( RAGE ) antibody respectively.The activity of NF - ΚB and the level of tumor necrosis factor α ( TNF -α) and interleukin 6 ( IL - 6 ) were measured.Results ( 1 ) Compared with the control group, there were no statistically significant difference on every detective parameter ( proliferation, migration, apoptosis and Caspase - 3 mRNA ) in BSA groups ( P > 0.05 ) .The cell proliferation, migration in AGEs groups became significantly weaker than those in BSA groups and control group ( P 0.05 ).Conclusion AGEs can inhibit the proliferation capacity of Schwann cells and accelerate the apoptosis in vitro, probably through promoting the production of inflammatory factors which are harmful to cells.

  17. pSVPoMcat微基因修饰雪旺细胞脊髓内移植对操作脊髓再生的影响%Influence of intraspinal implantation of pSVPoMcat genetically modified schwann cell on regeneration of injured spinal cord

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Objective In order to observe the role of genetically modified Schwann cell (SC) with pSVPoMcat in the regeneration of injured spinal cord.Method The cells were implanted into the spinal cord.Ninety SD rats were used to establish a model of hemi- transection of spinal cord at the level of T8,and were divided into three groups,randomly, that is,pSVPoMcat modified SC implantation(Group A), SC implantation(Group B),and without cell implantation as control(Group C).After three months the presence of axonal regeneration of the injured spinal cord was examined by means of horseradish peroxidase(HRP)retrograde labeling technique and stereography.Result The results indicated that HRP labeled cells in Group A and B could be found in the superior region of injured spinal cord and the brain stem such as the red nuclei and oculomotor nuclei. The density of ventral horn neurons of the spinal cord and the number of myelinated axons in 100 μ m of the white matter was A >B >C group.Conclusion In brief,the pSVPoMcat modified SC intraspinal implantation could promote regeneration of the injured spinal cord.

  18. 大鼠脂肪干细胞来源的施万细胞样细胞髓鞘形成能力的研究%Investigation of myelin formation ability in Schwann cell-like cells from rats adipose-derived stem cells

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    许勇峰; 刘岚

    2012-01-01

    目的 研究大鼠脂肪干细胞(ADSC)来源的施万细胞样细胞的髓鞘形成能力.方法 取大鼠脂肪组织分离、培养及鉴定ADSC,使用heregulin、成纤维细胞生长因子、血小板衍生生长因子和forskolin将ADSC诱导为施万细胞样细胞.将施万细胞样细胞和PC12细胞共培养.光镜(×100)下观察施万细胞样细胞的形态,免疫细胞化学染色检测其表面标志物表达,电镜观察其髓鞘形成能力.结果 大鼠ADSC均表达中胚层标志物fibronectin,极少数表达神经干细胞标志物nestin.ADSC诱导的施万细胞样细胞的形态为双极或三极细胞,施万细胞标志物胶质纤维酸性蛋白和S100表达阳性.电镜观察发现,施万细胞样细胞和PC12细胞形成髓鞘样结构.结论 大鼠ADSC来源的施万细胞样细胞具有髓鞘形成能力.%Objective To investigate the myelin formation ability of Schwann cell (SC)-like cells from rats adipose-derived stem cells (ADSC). Methods Rats ADSC were harvested, cultured and identified from rats fat tissue. Heregulin, basic fibroblast growth factor, platelet-derived growth factor and forskolin were used to induce rats ADSC into SC-like cells, which were then co-cultured with PC12 cells. The morphology of SC-like cells was observed under phase contrast (×100); immunocytochemistry was used to detect the surface markers of SC-like cells; transmission electron microscope was used to identify myelin formation ability of SC-like cells. Results Rats ADSC expressed mesodermal marker fibronectin, only few cells expressed neural stem cell marker nestin. SC-like cells from rats ADSC were bi- or tri- polar in shape, positively immunostained for SC markers glial fabrilary acidic protein and S100. Electron microscope results showed that SC-like cells could form myelin structures with PC12 cells in vitro. Conclusion SC-like cells from rats ADSC could form myelin in vitro.

  19. Differential astroglial responses in the spinal cord of rats submitted to a sciatic nerve double crush treated with local injection of cultured Schwann cell suspension or lesioned spinal cord extract: implications on cell therapy for nerve repair Respostas astrocitárias na medula espinal do rato submetido ao esmagamento duplo do nervo ciático e tratado com injeção local de suspensão de células de Schwann cultivadas ou de extrato de medula espinal lesada: implicações na terapia celular para o reparo do nervo

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    João Gabriel Martins Dallo

    2007-12-01

    Full Text Available PURPOSE: Reactive astrocytes are implicated in several mechanisms after central or peripheral nervous system lesion, including neuroprotection, neuronal sprouting, neurotransmission and neuropathic pain. Schwann cells (SC, a peripheral glia, also react after nerve lesion favoring wound/repair, fiber outgrowth and neuronal regeneration. We investigated herein whether cell therapy for repair of lesioned sciatic nerve may change the pattern of astroglial activation in the spinal cord ventral or dorsal horn of the rat. METHODS: Injections of a cultured SC suspension or a lesioned spinal cord homogenized extract were made in a reservoir promoted by a contiguous double crush of the rat sciatic nerve. Local injection of phosphate buffered saline (PBS served as control. One week later, rats were euthanized and spinal cord astrocytes were labeled by immunohistochemistry and quantified by means of quantitative image analysis. RESULTS: In the ipsilateral ventral horn, slight astroglial activations were seen after PBS or SC injections, however, a substantial activation was achieved after cord extract injection in the sciatic nerve reservoir. Moreover, SC suspension and cord extract injections were able to promote astroglial reaction in the spinal cord dorsal horn bilaterally. Conclusion: Spinal cord astrocytes react according to repair processes of axotomized nerve, which may influence the functional outcome. The event should be considered during the neurosurgery strategies.OBJETIVO: Astrócitos reativos participam de vários mecanismos após lesões do sistema nervoso central e periférico, os quais incluem neuroproteção, brotamento neuronal, neurotransmissão e dor neuropática. As células de Schwann (CS, um tipo de glia periférica, também reagem com a lesão do nervo, podendo interferir com o reparo e cicatrização, crescimento de fibras e regeneração neuronais. Investigamos aqui a possibilidade da terapia celular para o reparo do nervo ci

  20. Microgene pSVPoMcat implanted to modify Schwann cell and recovery of function after spinal cord injury%pSVPoMCAT微基因修饰雪旺氏细胞移植治疗实验性脊髓损伤的酶及免疫组化评价

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    陈礼刚; 朴永旭; 曾凡俊; 高立达; 毛伯镛; 杨立斌; 黄茂清; 胡威夷

    2002-01-01

    Objective To investigate the effect of microgene pSVPoMcat to modify genetically Schwann cell(SC) on recovery of function after spinal cord injury(SCI).Methods Experimental animals were divided into three groups:the group of microgene pSVPoMcat implanted to genetically(group A),SC implanted group(group B),and the control group(group C),each group having 10 animals.The cortical somatasensory evoked potentials(CSEP) and combined behavioral score(CBS) were continually monitored from operation second week to twelfth week.We used image analysis system to compare the latent period and peak amplitudes of CSEP and count the axon number among the different group.At the same time,electron microscope obsevation was conducted.Results The peak latency and amplitudes of group A,B showed a recovery tendency and it was constant with CBS.The number of regenerated axons of the group A and group B were (388± 163) and (109± 16),respectively(P < 0.01),in line with the observation of electron microscope.Conclusion We conclude that microgene pSVPoMcat to modify genetically SC plays a promoting role in recovery of central function after SCI.

  1. pSVPoMcat微基因修饰雪旺细胞脊髓内移植对损伤脊髓细胞的保护作用%Protective Effects of Intracord Transplantation of pSVPoMcat Modified Schwann Cells on Spinal Cord Injury

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    陈礼刚; 高立达; 曾凡俊; 毛伯镛

    2001-01-01

    Objective To study the protective effects of the intracord transplantation of microgene pSVPoMcat- genetically- modified Schwann cells (MSCs)on spinal cord injury (SCI).Method Rats with semi- division(SD) of the spinal cord was divided into 4 groups.Group S consisted of the rats with SD treated with the transplantation of MSCs, Group B of the rats with SD treated with the transplantation of SCs without genetic modification,Group C of the rats with SD without treatment and Group D was the normal control. 8 hours after operation,the half of the rats of each group were killed and the injured segment of the spinal cord was resected to be examined with atomic absorption spectrophotometry . Another half of the rats of all the groups were examined with neurological function tests to have a combined behavioral score (CBS).Result There was a significant increase of water content and Na+ and Ca2+ ions and a decrease of K+ and Mg 2+ ions in the injured cord segment of Group C and a statistically significant recovery was observed in Group A. The intracord transplantation of pSVPoMcat genetically modidied SCs improved the neurological outcome of spinal cord injury.Conclusion Our findings indicate that intracord transplantation of pSVPoMcat- genetically- modified- Schwanncells exerts protective effects on the injured segment of the spinal cord through the improvement of the internal ion environment of the spinal cord.

  2. 微囊化异种许旺细胞移植修复脊髓损伤的研究与进展%Research and progressions on transplantation of microencapsulated hetero-schwann cells in repair of spinal cord injury

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    傅文学; 刘小华; 刘德明

    2005-01-01

    OBJECTIVE: Neural tissue transplantation has been a hot topic in medical researches on treatment of spinal cord injury. It provides a certain action on repair of peripheral neural injury in which schwann cell contained. But homo-transplantation of neural tissue is limited at the provider source and provider injury and hetero-transplantation of neural tissue exists immune inhibition and rejection. Microencapsulated technology is a kind of satisfactory immune isolation means. Whether microencapsulated hetero-transplantation of neural tissue reduces immunological rejection and deals with provider source is probed into so as to provide a new channel for clinical treatment of spinal cord injury.DATA SOURCES: By computer retrieval system, the relevant papers on the researches on spinal cord injury were looked up medline 1984 -01/2004 -10, limiting at the referred word "schwann cells, transplantation, xenogenic,spinal cord injury" in English. Simultaneously, the relevant papers were looked up by the computer on Zhongguo Linchuang Kangfu 2002-01/2004 - 10, focusing on the referred word "Schwann cells, transplantation,heterogenous, spinal cord injury" in Chinese; and the free words were limited at "microencapsulated" and "rat".DATA SELECTION: Totally 30 papers were selected on the original literatures on researches on repair of spinal cord injury at home and abroad. The original literatures on non-randomized researches were excluded and those on non-blind researches were not excluded.DATA EXTRACTION: Of 30 papers on repair of spinal cord injury, 22papers compiled with the standards, 8 papers on repair of spinal cord injury were excluded because of the repeated same research. The rest 22 papers on repair of spinal cord injury were classified for summarization.DATA SYNTHESIS: Axonal regenerative disturbance is the main factor to the persistent disablement resulting from spinal cord injury. It was discovered by the thorough researches that the transplantation of schwann cell

  3. 人脐血间充质干细胞体外诱导分化为类雪旺细胞的初步研究%Experimental Study on the Differentiation of Human Umbilical Cord Blood Mesenchymal Stem Cells into Schwann Cell-like in Vitro

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    仇大鹏; 肖玉周

    2011-01-01

    目的:体外定向诱导人脐血间充质干细胞(HUCBMSCs),分化为类雪旺细胞(SC-like).方法:(1)采用Ficoll密度梯度离心法分离健康产妇脐带血中单个核细胞进行体外培养,用流式细胞术检测细胞表达的表面抗原CD90,SH2,CD34和CD45.(2)第3次传代所得的HUCBMSCs,加入加有β-巯基乙醇(β-ME)、全反式黄酸(RA)、Forskolin、b-FGF、PDGF、HRG的含10%胎牛血清(FBS)的低糖DMEM培养基(L-DMEM)诱导,7 d后免疫组织化学染色法检测.结果:(1)HUCBMSCs在体外培养以梭形细胞为主;流式细胞仪检测显示,细胞高表达表面抗原CD90和SH2,低表达表面抗原CD34和CD45.(2)诱导7 d后,细胞免疫组化显示,GFAP阳性率为81.88%±2.43%.结论:在一定条件下,HUCBMSCs可以在体诱导分化为SC-like,组成人工神经,移植修复周围神经缺损.%Objective:To induce the human umbilical cord blood mesenchymal stem cells (HUCBMSCs) to differentiate into schwann cell-like (SC-like) in vitro. Methods: ( 1 ) Mononuclear cells were separated from umbilical cord blood of healthy parturients by Ficoll density gradient centrifugation and cultured in vitro.The expression of surface antigens CD90, SH2, CD34 and CI45 were detected by flow cytometry (FCM). (2)The third passage cells were cultured in low carbohydrates~Dulbecco's modified eagle's medium ( L-DMEM )containing 10% fetal bovine serum(FBS), β-mercaptoethanol (β-ME), retinoic acid(RA), forskolin, basic fibroblast growth factor (b-FGF), platelet-derived growth factor(PDGF) and beregulin(HRG). On 7th day,the cells were identified by immunocytocbemistry. Results: ( 1 )The majority of HUCBMSCs cultured in vitro displayed a spindle shaped appearance. FCM showed that the surface antigens CD90 and SH2 were highly expressed in these cells, while the CD34 and CD45 were very low. (2) On 7th day, the results of immunocytochemistry showed that the cells were positive for GFAP. The positive percentageswere 81.88% ± 2.43

  4. Expression of brain-derived neurotrophic factor gene in cultured Schwann cell introduced by adenoviral vector%腺病毒介导脑源性神经营养因子基因在培养的雪旺细胞中的表达

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    卢春光; 胡丹; 惠延年

    2006-01-01

    目的:观察腺病毒介导人脑源性神经营养因子(brain-derived neurotrophic factor,BDNF)基因在培养的雪旺细胞(Schwann cell, SC)中的表达,为视神经损伤修复提供可靠的组织工程用的种子细胞.方法:在293细胞中培养扩增BDNF重组腺病毒(adenovirall delivered BDNF,Ad-BDNF),采用蚀斑形成试验测定其感染滴度.体外培养SD大鼠源性的SC,以Ad-BDNF感染培养的SC,用逆转录-聚合酶链反应(reverse transcriptase polymerse chain reaction,RT-PCR)检测BDNF mRNA的表达,用免疫印迹技术(immunoblot assay,Western Blotting)和酶联免疫反应检测(enzyma-linked immumosorbent assay,ELISA)培养液上清中BDNF的表达.结果:Ad-BDNF经扩增后可获得较高感染滴度的重组腺病毒载体.在正常培养条件下未经Ad-BDNF感染的SC低表达BDNF,而感染3d后的SC其BDNF表达明显升高,表达量随时间延长而增加,并能在感染21d后仍维持高表达趋势.结论:Ad-BDNF可以介导BDNF基因转染到培养的SC中,后者可以在较长时间内高效表达BDNF.

  5. 许旺细胞源神经营养因子对脊髓背根节感觉神经元的保护作用%Protective effect of Schwann cell-derived neurotrophic factor on sensory neurons in spinal dorsal root ganglia

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    刘黎军; 朱家恺; 王大平; 肖建德; 杨雷

    2006-01-01

    BACKGROUND: Schwann cell-derived neurotrophic factor is a bioactive protein isolated and purified from the kytoplasm of Schwann cell. It can obviously maintain the survival of spinal cord anterior horn motor neuron and promote the regeneration of peripheral nerve.OBJECTIVE: To observe the protective effect of Schwann cell-derived neurotrophic factor on the high injury of peripheral nerve-induced apoptosis of sensory neurons in spinal dorsal root ganglia.DESIGN: Randomized and controlled animal experiment.SETTING: Shenzhen Second People's Hospital.MATERIALS: Totally 30 3-week-old SD infant rats, of clean grade and either gender, were used in this experiment. They were randomly divided into neurotrophic factor group and control group with 15 rats in each one.Left sides of the animals in both two groups were set as normal sides and right sides as injured sides.METHODS: This experiment was carried out at the Experimental Animal Center, Medical College of Sun Yat-sen University from May 2003 to July 2003. ① L4.5 nerve root high-mutilation animal models were developed on the rats in two groups. Proximal nerve stump was connected with silicone tube. According to grouping, 60 mg/L Schwann cell-derived neurotrophic factors and 20 μL normal saline were injected into the silicone tubes respectively. Two ends of silicone tube were enveloped with vaseline.② Sample collecting was conducted at postoperative 4 weeks, survival rate and morphological change of sensory neurons in dorsal root ganglia of injured nerve was observed.MAIN OUTCOME MEASURES: ① Gross observation of sciatic nerve regeneration at injured side of the rats in two groups ② Survival of sensory neurons in dorsal root ganglia ③ Morphological change of sensory neurons in dorsal root ganglia.RESULTS: All the 30 rats entered the stage of result analysis. ① Gross observation of sciatic nerve regeneration: In the neurotrophic factor group,nerve new born axon grew along silicone tube, with 1cm in length

  6. Protective effects of Schwann cells transfected with brain-derived neurotrophic factor gene mediated by recombinant adenovirus on repair of injured optic nerve in rat%腺病毒介导BDNF基因转染的雪旺细胞对大鼠视神经损伤修复的保护作用

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    卢春光; 胡丹; 惠延年

    2006-01-01

    目的研究经腺病毒介导,转染有人脑源性神经营养因子(brain-derived neurotrophic factor,BDNF)基因的SD大鼠雪旺细胞(Schwann cells,SCs)对成年SD大鼠视神经夹伤后修复的保护作用.方法将人BDNF基因转染到体外培养的SCs内,采用酶联免疫反应(enzyma-linked immumosorbent assay,ELISA)检测培养液上清中BDNF的表达量.80只成年SD大鼠随机分为转染有BDNF基因的SCs治疗组(A组)、正常SCs治疗组(B组)、DMEM治疗组(C组)和手术对照组(D组),每组20只,每只右眼建立视神经夹伤模型,D组大鼠左眼作为空白对照组(E组).夹伤前7 d进行荧光金(fluorogold,FG)逆行标记视网膜神经节细胞(retinal ganglial cells,RGCs).夹伤后即刻向A、B、C组伤眼玻璃体腔内注入相应液体各10 μL.分别在伤后第7 d、14 d、21 d、28 d时进行闪光视觉诱发电位(flash visual evoked potentials, FVEP)检测和全视网膜铺片、记数RGCs.结果转染有BDNF基因的SCs的BDNF表达量明显高于正常SCs.A组的P1波幅比随观察时间延长呈下降趋势,但在夹伤后第14 d、21 d、28 d时仍明显高于其他各组(P《0.05).夹伤后第21 d和第28 d时,A组RGCs数分别为(1 591±82)·mm-2、(1 516±91)·mm-2,明显高于除E组外的其他各组(P《0.01).结论视神经夹伤后,玻璃体腔内注射转染有BDNF基因的SCs能够促进RGCs轴突的修复,提高RGCs存活率,保护视神经功能,对视神经损伤修复具有明显的保护作用.

  7. 吡咯喹啉醌对氧化应激诱导雪旺细胞凋亡的保护作用及其机制%Effects of Pyrroloquinoline quinine on oxidative stress-induced apoptosis of Schwann cells and its mechanism

    Institute of Scientific and Technical Information of China (English)

    贺斌; 陶海鹰; 卫爱林; 刘世清; 李皓桓

    2014-01-01

    目的 探讨吡咯喹啉醌(Pyrroloquinoline quinine,PQQ)对H2O2诱导雪旺细胞(Schwann cells,SCs)凋亡的保护作用及其作用机制.方法 体外原代培养、纯化及S-100免疫荧光染色鉴定SCs,将培养SCs分为空白对照组、H2O2处理组(100 μmol/L H2O2诱导组)、H2O2加PQQ处理组(10、50和100 nmoL/L PQQ处理组).检测各组细胞内超氧化物歧化酶(SOD)及丙二醛(MDA)的含量,流式细胞仪计数检测SCs早期凋亡率,Hoeehst33342染色观察凋亡SCs核碎裂及核固缩情况,亲脂性阳离子荧光染料罗丹明染色(Rhodamine 123,Rho123)观察凋亡SCs线粒体膜电位变化情况,Western blot法检测Bcl-2的表达水平.结果 经H2O2诱导,SCs组与空白对照组比较SOD含量明显减少,MDA含量明显增加(P<0.05);加入PQQ后SOD含量增加,MDA含量减少(P<0.05).流式细胞仪检测结果表明,经H2O2诱导SCs早期凋亡率为58.8%,与空白对照组(2.1%)比较差异有统计学意义(P<0.05),加入10、50、100 nmol/L PQQ后凋亡率分别降低为33.7%、18.7%、3.9%,差异有统计学意义(P<0.05).Hoeehst33342染色结果表明,H2O2诱导SCs具有典型的凋亡形态特征,表现为核染色质浓聚、细胞核体积缩小、核碎裂现象明显,经PQQ作用后凋亡形态细胞比例减少.Rho123染色结果表明,经H2O2诱导后SCs线粒体膜电位明显降低,而经PQQ作用后部分逆转.Western blot结果表明,经H2O2诱导SCs后Bcl-2表达下调,加入PQQ后Bcl-2表达有所增加,差异有统计学意义(P<0.05).结论 PQQ对氧化损伤SCs凋亡具有保护作用.%Objective To investigate the effects of Pyrroloquinoline quinine (PQQ) on hydrogen peroxide-induced apoptosis of Schwann cells (SCs) and its mechanism.Methods SCs were isolated and cultured in vitro,and identified by S-100 immunofluorescence staining.The cultured SCs were divided into control group、hydrogen peroxide-treated group、hydrogen peroxide and PQQ treated groups.The intracellular

  8. MicroRNA-21 can promote the differentiation of neural crest stem cells from human follicle into Schwann cells%miR-21促进毛囊神经嵴干细胞分化为许旺细胞

    Institute of Scientific and Technical Information of China (English)

    王艳华; 刘浩; 辛红; 白晓雪; 刘学娟; 倪宇昕

    2014-01-01

    BACKGROUND:MicroRNAs are a class of non-coding single-stranded smal RNA molecules containing 18–25 nucleotides that can bind to the 3’UTR of the mRNA molecules and regulate the protein expression of target genes. Studies have shown that microRNAs could regulate Schwann cel differentiation, myelination maturation and growth of the peripheral nerve. OBJECTIVE: To observe the expression of miR-21 during the differentiation of neural crest stem cels from human folicle into Schwann cels. METHODS: Hair folicle stem cels were cultured and neural crest stem cels were separated from human hair folicles by flow cytometry. Then, the neural crest stem cels were induced to differentiate into Schwann cels. qRT-PCR was used to detect the expression of miR-21 in the process of induction. Neural crest stem cels from hair folicles were divided into control group, agomir-21 group, agomir-NC group, antagomir-21 group and antagomir-NC group. The control group was without intervention. Agomir-21 group was transfected with miR-21 agonist, whereas Antagomir-21 group was transfected with miR-21 antagonist. agomir-NC group and antagomir-NC group were respectively negative controls of agomir-21 group and antagomir-21 group. Finaly, the possible target of miR-21 was searched in database. RESULTS AND CONCLUSION: Neural crest stem cels were successfuly separated from human hair folicles using flow cytometry and induced to differentiate into Schwann cels. In the process of cel differentiation, miR-21 expression was upregulated gradualy. Transfection of miR-21 agonist could enhance the stem cel differentiation into Schwann cels, whereas transfection of miR-21 antagonist could weaken the differentiation capacity of stem cels. Furthermore, we found via database searching that SOX2 maybe a target of miR-21 and participate in the regulatory role of miR-21. This study suggested that hair folicle neural crest stem cels can be used as an important source of Schwann cels and miR-21 can promote the

  9. EXPERIMENTAL STUDY ON CULTIVATION AND PURIFICATION OF Schwann CELLS AND ITS COMPOSITION WITH SMALL INTESTINAL SUBMUCOSA IN VITRO%雪旺细胞纯化培养及体外复合猪小肠黏膜下层的实验研究

    Institute of Scientific and Technical Information of China (English)

    刘宏银; 冯喆; 柏琳; 侯江龙; 罗静聪; 杨志明; 解慧琪

    2013-01-01

    Objective To obtain highly purified and large amount of Schwann cells (SCs) by improved primary culture method,to investigate the biocompatibility of small intestinal submucosa (SIS) and SCs,and to make SIS load nerve growth factor (NGF) through co-culture with SCs.Methods Sciatic nerves were isolated from 2-3 days old Sprague Dawley rats and digested with collagenase Ⅱ and trypsin.SCs were purified by differential adhesion method for 20 minutes and treated with G418 for 48 hours.Then the fibroblasts were further removed by reducing fetal bovine serum to 2.5% in H-DMEM.MTT assay was used to test the proliferation of SCs and the growth curve of SCs was drawn.The purity of SCs was calculated by immunofluorescence staining for S-100.SIS and SCs at passage 3 were co-cultured in vitro.And then the adhesion,proliferation,and differentiation of SCs were investigated by optical microscope and scanning electron microscope (SEM).The NGF content by SCs was also evaluated at 1,2,3,4,5,and 7 days by ELISA.SCs were removed from SIS by repeated freeze thawing after 3,5,7,10,13,and 15 days of co-culture.The NGF content in modified SIS was tested by ELISA.Results The purity of SCs was more than 98%.MTT assay showed that the SCs entered the logarithmic growth phase on the 3rd day,and reached the plateau phase on the 7th day.SCs well adhered to the surface of SIS by HE staining and SEM; SCs were fusiform in shape with obvious prominence and the protein granules secreted on cellular surface were also observed.Furthermore,ELISA measurement revealed that,co-culture with SIS,SCs secreted NGF prosperously without significant difference when compared with the control group (P > 0.05).The NGF content increased with increasing time.The concentration of NGF released from SIS which were cultured with SCs for 10 days was (414.29 ± 20.87) pg/cm2,while in simple SIS was (4.92 ± 2.06) pg/cm2,showing significant difference (P < 0.05).Conclusion A large number of highly purified SCs can

  10. 胶原/丝素导管介导雪旺细胞联合神经干细胞修复坐骨神经缺损%Collagen/silk fibroin conduit combined with the co-culture of Schwann cells and neural stem cells for bridging sciatic nerve defect

    Institute of Scientific and Technical Information of China (English)

    徐云强; 张振辉; 余欣; 陈旭义; 李东; 李瑞欣; 冯世庆

    2015-01-01

    目的 观察胶原/丝素导管介导雪旺细胞联合神经干细胞所构建的组织工程化神经修复大鼠10 mm坐骨神经缺损的效果.方法 体外分离培养乳鼠坐骨神经雪旺细胞(SCs),并做S-100蛋白免疫荧光鉴定;从孕14 ~ 15 d的SD大鼠体内取出子鼠,分离纯化获得原代神经干细胞(NSCs)进行体外培养.实验分为4组,每组10只:自体神经移植组(A组)、胶原/丝素导管介导雪旺细胞联合神经干细胞移植组(B组)、胶原/丝素导管移植组(C组)、单纯损伤组(D组).SCs-NSCs与胶原/丝素导管联合培养14 d后,行扫描电镜观察.分别将3种不同移植物桥接于大鼠坐骨神经10 cm缺损处,并在12周后进行大体观察、电生理学检测、形态学观察及计量学分析.结果 术后12周,桥接组都不同程度地实现了坐骨神经缺损再通,且实验动物未出现明显排斥及炎性反应.神经电生理学检测坐骨神经复合肌动作电位(CMAPs)波幅分别为:未手术正常侧(21.00±1.83) mV,A组(15.00±1.12) mV,B组(13.00±1.06) mV,C组(6.00±0.58) mV,透射电子显微镜再生神经纤维髓鞘厚度分别为:A组(0.80±0.15) μm,B组(0.70±0.11) μm,C组(0.30±0.07) μm,D组(0.25±0.06) μm.统计结果表明:A组与B组之间差异无统计学意义(P>0.05),但两者相对C组及D组差异有统计学意义(P<0.05).结论 SCs和NSCs能够在胶原/丝素导管上共同生长分化,生物相容性良好.胶原/丝素导管介导雪旺细胞联合神经干细胞所构建的组织工程化神经对坐骨神经缺损的修复具有良好的桥接和促神经生长作用.%Objective To observe the repair effect of collagen/silk fibroin conduit transplanted with co-cultured Schwann cells (SCs) and neural stem cells (NSCs) for bridging 10 mm sciatic nerve defect by tissue engineering technique in rats.Methods SCs were isolated and purified from the sciatic nerve of neonatal SD rats,and were identified by immunocytochemical labelling for S100

  11. Repairment of sciatic nerve defect by Schwann cell of adult rat combined with acellular nerve grafts%成年大鼠许旺细胞复合去细胞神经支架修复坐骨神经缺损

    Institute of Scientific and Technical Information of China (English)

    周丽娜; 崔晓军; 苏开鑫; 王晓红; 蔡雪彦; 郭金华; 纳青青

    2015-01-01

    目的:探讨成年许旺细胞(SC)复合去细胞神经支架构建的组织工程化人工神经移植治疗外周神经损伤的效果。方法从 Wallerian 变性1周的成年 SD 大鼠远侧端神经中分离培养得到SC,复合去细胞神经支架构建组织工程化人工神经。移植分为 SC +去细胞 SD 大鼠神经支架组(SC治疗组)和空细胞 SD 大鼠神经支架组(阴性对照组),每组各5只。比较两组大鼠术后2、4、8周损伤侧坐骨神经功能指数(SFI),术后 8周损伤侧坐骨神经传导功能和小腿三头肌湿重恢复率等修复效果的指标。结果SC 治疗组术后2、4、8周损伤侧 SFI,术后 8周损伤侧坐骨神经传导功能和小腿三头肌湿重恢复率均优于或高于阴性对照组(均为 P <0.05)。结论采用成年 SC 复合去细胞神经支架的人工神经移植治疗外周神经缺损,可有效促进损伤神经的功能恢复。%Objective To investigate clinical efficacy of tissue-engineered artificial nerve grafts constructed by acellular nerve grafts combined with adult rat Schwann cell (SC)in the treatment of peripheral nerve injury.Methods SCs were isolated and cultured from the distal nerves of adult Sprague Dawley (SD) rats with 1-week Wallerian degeneration and then combined with acellular nerve grafts to construct tissue-engineered artificial nerve.All rats were divided into acellular nerve graft containing SCs (SC group)and nerve graft containing no cells groups (control group),five animals in each group.At 2-,4-and 8-week after surgery,sciatic function index (SFI)of the affected side was compared between two groups.At postoperative 8 weeks,nerve conduction of sciatic nerve of the injured side,recovery rate of triceps surae wet weight and other relevant parameters were equally compared between two groups.Results In the SC group,SFI of the affected side at 2-,4-and 8-week after surgery,nerve conduction of sciatic nerve at the injured side

  12. 不同浓度许旺细胞与聚乳酸-聚羟基乙酸共聚物修复损伤周围神经的比较%Polylactic-co-glycolic acid complex with different concentrations of Schwann cells for peripheral nerve regeneration

    Institute of Scientific and Technical Information of China (English)

    孙焕伟; 张铁慧; 由欣岩; 任远飞; 钟声

    2014-01-01

    背景:有研究表明,许旺细胞神经移植复合体具有极强修复自体神经缺损作用,并且许旺细胞在神经再生过程中发挥至关重要的作用。目的:比较不同浓度许旺细胞神经移植复合体修复自体神经缺损时周围神经的再生效果。方法:建立坐骨神经缺损模型大鼠。原代培养大鼠许旺细胞,构建聚乳酸-聚羟基乙酸共聚物管-细胞外基质凝胶-许旺细胞神经移植复合体修复坐骨神经缺损模型大鼠。按许旺细胞浓度的不同分为105,106,107,108,109 L-1结果与结论:建模后3,6和12周,含许旺细胞各浓度的神经移植复合体组各时间点神经传导速率均高于对照组(P <0.01),其中10浓度组,对照组不含许旺细胞。分别于建模后3,6和12周,行运动神经传导速度的测定。建模后12周各组胫骨前肌湿质量测量和组织学观察。8 L-1组运动神经传导速度优于其他各浓度组(P <0.05)。建模后12周,大鼠胫骨前肌苏木精-伊红染色显示,各浓度许旺细胞神经移植复合体组正常肌纤维数均多于对照组(P <0.05)。其中许旺细胞浓度108,109 L-1浓度组胫骨前肌形态恢复较好,肌纤维细条样、波浪状,同向而行,长短、粗细及疏密大致一致。结果证实,108 L-1许旺细胞神经聚乳酸-聚羟基乙酸共聚物移植复合体对缺损坐骨神经再生的促进作用较好。%BACKGROUND:Studies have shown that nerve grafts with Schwann cels can repair peripheral nerve defect and Schwann cels have an important role in nerve regeneration. OBJECTIVE: To observe the rehabilitation status of neutral function after sciatic nerve injury in rats bridged by nerve grafts with Schwann cels. METHODS: A rat model of sciatic nerve injury was established, and schwann cels were primarily cultured. Then, the rat model was repaired with polylactic-co-glycolic acid copolymer-extracelular matrix gel-Schwann cels complex

  13. 脑源性神经营养因子辅助施万细胞治疗实验性自身免疫性神经炎%Therapeutic potential of brain-derived neurotrophic factor and Schwann cells transplantation in experimental autoimmune neuritis

    Institute of Scientific and Technical Information of China (English)

    侯晓君; 梁庆成; 吴云

    2013-01-01

    Objective To investigate the therapeutic potential of brain-derived neurotrophic factor (BDNF) and Schwann cells(SCs) in experimental autoimmune neuritis (EAN) and assess the effect and mechanism.Methods EAN model was established by immunization of Lewis rats with 400 μg of specific peptide P2(57-81)and complete Freund adjuvant.In the therapy group,the SCs (n =28) and the combination of BDNF administration and SCs (n =48) were labeled by the nuclear fluorescent dye injected into the intracerebroventricularly in 14 d after immunization.Transplanted cell migration tracking respectively were at 25,35 and 45 days after immunization.The rats were observed for signs of disease daily and subjected to clinical score,of which the sciatic nerves were subjected to histopathological examination (hematoxylin eosinstaining,luxol-fast-green and immunohistochemical staining).The inflammatory cell infiltration and demyelination were assessed,and the CD4,CD8,CD68,S-100 and nerve growth factor (NGF) positive cells numbers were compared among the 3 different groups.Results AIl the rats had the neurological deficits.Compared with control group,there were no significant differences in SCs therapy group.In SCs + BDNF therapy group,the recovery of paralytic symptom was faster and the score was lower after immunization 45 d.After immunization 25 and 35 days,both the inflammatory cells infiltration (EAN model group:325.8 ±10.8,221.4 ± 35.2;SCs + BDNF transplantation group:307.3 ±4.6,197.2 ± 16.8; t =2.172,P =0.031 ;t=3.756,P=0.000) and the expression of CD4+,CD8+ T cells and CD68+ macrophages were reduced.After immunization 35,45 days,the demyelination degree (EAN model group:3.4 ± 0.5,2.9 ± 0.8 ; SCs +BDNF transplantation group:2.9 ±0.8,2.3 ±0.5) was reduced (t =-7.408,P =0.000;t =-6.092,P =0.000),the expression of S-100 is higher,and NGF was lower than the control group in each time point after immunization.Conclusions SCs transplanted into the cerebellar ventricle of animals can

  14. Switchable cell trapping using superparamagnetic beads

    Energy Technology Data Exchange (ETDEWEB)

    Bryan, M. T.; Smith, K. H.; Real, M. E.; Bashir, M. A.; Fry, P. W.; Fischer, P.; Im, M.-Y.; Schrefl, T.; Allwood, D. A.; Haycock, J. W.

    2010-04-30

    Ni{sub 81}Fe{sub 19} microwires are investigated as the basis of a switchable template for positioning magnetically-labeled neural Schwann cells. Magnetic transmission X-ray microscopy and micromagnetic modeling show that magnetic domain walls can be created or removed in zigzagged structures by an applied magnetic field. Schwann cells containing superparamagnetic beads are trapped by the field emanating from the domain walls. The design allows Schwann cells to be organized on a surface to form a connected network and then released from the surface if required. As aligned Schwann cells can guide nerve regeneration, this technique is of value for developing glial-neuronal co-culture models in the future treatment of peripheral nerve injuries.

  15. Cultivo de células de Schwann, un modelo del microambiente del sistema nervioso

    Directory of Open Access Journals (Sweden)

    Vilma C. Muñetón

    1998-03-01

    Full Text Available Algunos aspectos de la fisiopatología del sistema nervioso periférico pueden ser ampliamente estudiados en un modelo celular in vitro, enriquecido en células de Schwann. La célula de Schwann como glía del sistema nervioso periférico produce la mielina responsable de la transmisión saltatoria del impulso, influye en la actividad neuronal y da soporte y protección axonal. A su vez es blanco de procesos que alteran la normalidad del sistema nervioso periférico como neuropatías congénitas y 10 desmielinizantes, lesiones nerviosas, respuesta a patógenos neurotrópicos, etc., eventos más frecuentes y discapacitantes en individuos adultos. De ahí la importancia de obtener células a partir de animales adultos. Sin embargo, estas células son mitóticamente ""lentas"" y su obtención en cultivo requiere de condiciones específicas que estimulen su proliferación y actividad. Describimos a continuación, un modelo in vitro mediante el cual se obtienen cultivos enriquecidos en células de Schwann de ratón adulto, las cuales conservan características de las células in vivo, lo cual permite estudiar diversos fenómenos específicos del sistema nervioso periférico.

  16. Effects of erythropoietin on cell cycle and neurotrophic factor secretion of Schwann cells in vitro%红细胞生成素对体外培养许旺细胞增殖周期及其分泌神经营养因子的影响

    Institute of Scientific and Technical Information of China (English)

    曹能力; 吴学建; 朱旭; 王楷

    2009-01-01

    Objective To observe the effects of EPO on cell cycle and the secretion of NGF and CNTF of SCs in vitro and explore how EPO improve peripheral nerve regeneration. Methods The sciatic nerves of the adult New Zealand rabbits were ligated and pre - degenerated. Mter a week, the pre - degenerated nerves were fetched and their ectoblastics were removed. We adopted a method of trasplant piece and speed difference adhestion to cultivte and purify SCs. Different concentrations of EPO were added into cutures of puri-fied SCs respectively. The cell cycle distribution of SCs.was observed by flow cytometry, and the level of NGFand CNTF in the culture was detected by ELSIA. Results In the EPO supplemention group,the number of SCs in S phase(S%) was significantly increased,G1% obviously decreased and the PrI[(S + G2M)%] enhanced when the SCs were stimulated. Conclusions EPO enhance SCs proliferation activity and increase the secretion of neurotrophic factors, which may be explain how EPO improve peripheral nerve regeneration.%目的 观察促红细胞生成素(EPO)对体外培养许旺细胞(SCs)增殖周期及其分泌神经生长因子(NGF)和睫状神经生长因子(CNTF)的影响,探讨EPO促进周围神经再生的机制.方法 对成年新西兰兔的坐骨神经进行结扎顸变性,1周后取预变性的坐骨神经,剥净神经外膜,用植块法、差速贴壁法培养纯化许旺细胞,向培养基中加入不同剂量的EPO,通过流式细胞术检测细胞增殖周期分布,应用ELISA测定培养上清液中的NGF和CNTF水平.结果 与对照组相比,实验组许旺细胞处于S期数量(S%)和增殖指数PrI值[(S+G2M)%]都有明显升高,培养上清液中的NGF和CNTF水平明显增高.结论 EPO可提高体外培养许旺细胞的增殖活性,并且能提高许旺细胞分泌神经营养因子的水平,这可能是其促进周围神经再生的作用机制之一.

  17. Glial cell biology in the Great Lakes region.

    Science.gov (United States)

    Feinstein, Douglas L; Skoff, Robert P

    2016-03-31

    We report on the tenth bi-annual Great Lakes Glial meeting, held in Traverse City, Michigan, USA, September 27-29 2015. The GLG meeting is a small conference that focuses on current research in glial cell biology. The array of functions that glial cells (astrocytes, microglia, oligodendrocytes, Schwann cells) play in health and disease is constantly increasing. Despite this diversity, GLG meetings bring together scientists with common interests, leading to a better understanding of these cells. This year's meeting included two keynote speakers who presented talks on the regulation of CNS myelination and the consequences of stress on Schwann cell biology. Twenty-two other talks were presented along with two poster sessions. Sessions covered recent findings in the areas of microglial and astrocyte activation; age-dependent changes to glial cells, Schwann cell development and pathology, and the role of stem cells in glioma and neural regeneration.

  18. 纤维蛋白胶支架搭载外胚间充质源雪旺细胞移植修复大鼠脊髓损伤%Transplantation of fibrin scaffolds containing ectomesenchymal Schwann cells to repair the spinal cord injury in rats

    Institute of Scientific and Technical Information of China (English)

    崔学文; 李正南; 张志坚; 张雪松; 贺清华; 束浩明; 王穆彬; 刘伦

    2015-01-01

    目的:观察外胚层间充质源的雪旺细胞在损伤脊髓中的迁移情况、组织相容性,评价纤维蛋白支架搭载该细胞移植治疗急性脊髓损伤的疗效.方法:(1)成年大鼠鼻中隔活体取出部分鼻黏膜制成细胞悬液,自然纯化并扩增鼻黏膜外胚层间充质干细胞(ectomesenchymal stem cells,EMSCs),用雪旺细胞诱导培养基将其诱导为雪旺细胞并用红色荧光进行标记.(2)建立脊髓针刺损伤模型并移植标记细胞,术后10 d,观察雪旺细胞在组织内的存活和迁移情况,并评价其组织相容性.(3)健康SD大鼠60只,制作脊髓横断模型,随机分为3组:单纯脊髓横断(SCI)组、纤维蛋白胶(Fibrin)移植组和细胞-支架(F-C)移植组,术后每周进行运动行为学评分.术后12周取出脊髓组织,采用免疫组织化学染色和Western Blot方法检测脊髓横断部位神经纤维重建和髓鞘再生情况,以及神经丝蛋白(NF-200)、生长相关蛋白-43(GAP-43)和髓鞘碱性蛋白(MBP)的表达变化.结果:(1)EMSCs来源的雪旺细胞体外分化扩增良好,免疫荧光结果显示其高表达S100、GFAP、P75、CNpase等表面标志蛋白.(2)移植进入体内的雪旺细胞存活良好并发生一定距离的迁移,且与脊髓内神经纤维有良好的相容性.(3)术后2周开始直至12周,F-C组较SCI组大鼠后肢运动功能有较明显恢复,差异有显著意义(P<0.05);Fibrin组亦有一定程度的恢复,但程度较轻;SCI组几乎没有恢复迹象.免疫组化染色结果显示:SCI组断端未见神经轴索通过,Fi-brin组可见少量神经纤维通过,F-C组可见多量神经网络状结构.Western Blot检测结果显示:F-C组神经丝蛋白(NF-200)、生长相关蛋白-43(GAP-43)和髓鞘碱性蛋白(MBP)相对含量均高于Fibrin组和SCI组(P<0.05).结论:外胚层间充质源雪旺细胞移植对于脊髓损伤后的组织学和功能学恢复有明显促进作用,纤维蛋白做为移植修复脊髓损伤的生物

  19. Expression of polysialylated neural cell adhesion molecules on adult stem cells after neuronal differentiation of inner ear spiral ganglion neurons.

    Science.gov (United States)

    Park, Kyoung Ho; Yeo, Sang Won; Troy, Frederic A

    2014-10-17

    During brain development, polysialylated (polySia) neural cell adhesion molecules (polySia-NCAMs) modulate cell-cell adhesive interactions involved in synaptogenesis, neural plasticity, myelination, and neural stem cell (NSC) proliferation and differentiation. Our findings show that polySia-NCAM is expressed on NSC isolated from adult guinea pig spiral ganglion (GPSG), and in neurons and Schwann cells after differentiation of the NSC with epidermal, glia, fibroblast growth factors (GFs) and neurotrophins. These differentiated cells were immunoreactive with mAb's to polySia, NCAM, β-III tubulin, nestin, S-100 and stained with BrdU. NSC could regenerate and be differentiated into neurons and Schwann cells. We conclude: (1) polySia is expressed on NSC isolated from adult GPSG and on neurons and Schwann cells differentiated from these NSC; (2) polySia is expressed on neurons primarily during the early stage of neuronal development and is expressed on Schwann cells at points of cell-cell contact; (3) polySia is a functional biomarker that modulates neuronal differentiation in inner ear stem cells. These new findings suggest that replacement of defective cells in the inner ear of hearing impaired patients using adult spiral ganglion neurons may offer potential hope to improve the quality of life for patients with auditory dysfunction and impaired hearing disorders. Crown Copyright © 2014. Published by Elsevier Inc. All rights reserved.

  20. From stem cells to Schwann cells : potential applications of iPS cells and neural crest stem cells

    NARCIS (Netherlands)

    Ma, Ming San

    2015-01-01

    Geïnduceerde pluripotente stamcellen, oftewel iPS-cellen, zijn stamcellen met soortgelijke eigenschappen als embryonale stamcellen. iPS-cellen kunnen gegenereerd worden uit somatische cellen door deze met specifieke pluripotentiefactoren te reprogrammeren tot een basale stamceltoestand. Onze resulta

  1. Premigratory and migratory neural crest cells are multipotent in vivo

    NARCIS (Netherlands)

    Baggiolini, Arianna; Varum, Sandra; Mateos, José María; Bettosini, Damiano; John, Nessy; Bonalli, Mario; Ziegler, Urs; Dimou, Leda; Clevers, Hans; Furrer, Reinhard; Sommer, Lukas

    2015-01-01

    The neural crest (NC) is an embryonic stem/progenitor cell population that generates a diverse array of cell lineages, including peripheral neurons, myelinating Schwann cells, and melanocytes, among others. However, there is a long-standing controversy as to whether this broad developmental

  2. Premigratory and migratory neural crest cells are multipotent in vivo

    NARCIS (Netherlands)

    Baggiolini, Arianna; Varum, Sandra; Mateos, José María; Bettosini, Damiano; John, Nessy; Bonalli, Mario; Ziegler, Urs; Dimou, Leda; Clevers, Hans; Furrer, Reinhard; Sommer, Lukas

    2015-01-01

    The neural crest (NC) is an embryonic stem/progenitor cell population that generates a diverse array of cell lineages, including peripheral neurons, myelinating Schwann cells, and melanocytes, among others. However, there is a long-standing controversy as to whether this broad developmental perspect

  3. The Role of Axon-Schwann Cell Interactions in Nervous System Ionic Homeostasis

    Science.gov (United States)

    1993-06-08

    systems. That is, glutamine synthetase , the enzyme required for conversion of glu- tamate to glutamine is almost exclusively compatmentalized to the...Immunolocytochemicai localization of glutamine synthetase and glutaminase in the giant axon of crayfish. Transactions of the American Society for

  4. A role of peripheral myelin protein 2 in lipid homeostasis of myelinating Schwann cells.

    NARCIS (Netherlands)

    Zenker, Jennifer; ruskamo, salla; domenech-estevez, Enric; medard, jean-jacques; Verheijen, M.H.; Brouwers, Jos; Kursula, Petri; kieseier, bernd; Chrast, Roman

    2014-01-01

    Peripheral myelin protein 2 (Pmp2, P2 or Fabp8), a member of the fatty acid binding protein family, was originally described together with myelin basic protein (Mbp or P1) and myelin protein zero (Mpz or P0) as one of the most abundant myelin proteins in the peripheral nervous system (PNS). Although

  5. Fourth Ventricular Schwannoma: Identical Clinicopathologic Features as Schwann Cell-Derived Schwannoma with Unique Etiopathologic Origins

    Directory of Open Access Journals (Sweden)

    Tiffany R. Hodges

    2011-01-01

    Full Text Available Background. To our knowledge, this is the sixth reported case in the literature of fourth ventricular schwannoma. The etiology and natural history of intraventricular schwannomas is not well understood. A thorough review of potential etiopathogenic mechanisms is provided in this case report. Case Description. A 69-year-old man presented with an incidentally found fourth ventricular tumor during an evaluation for generalized weakness, gait instability, and memory disturbance. Magnetic resonance imaging (MRI revealed a heterogeneously enhancing lesion in the fourth ventricle. A suboccipital craniotomy was performed to resect the lesion. Histopathological examination confirmed the diagnosis of schwannoma (WHO grade I. Conclusions. Schwannomas should be considered in the differential diagnosis of intraventricular tumors. Although the embryologic origins may be different from nerve sheath-derived schwannomas, the histologic, clinical, and natural history appear identical and thus should be managed similarly.

  6. A Combination Tissue Engineering Strategy for Schwann Cell-Induced Spinal Cord Repair

    Science.gov (United States)

    2015-10-01

    rat embryos were seeded on the SC-laden scaffolds and the co-culture was maintained for 2 days in D10 media or D10 containing nerve growth factor...at the time of transplantation on axonal growth. The goal of this study was to evaluate whether fiber filled conduits enhanced axonal growth without...Surgical methods are described below. Animals were euthanized 3 weeks post transplantation and cryocut into 20µm thick sagittal sections

  7. Olfactory ensheathing cell tumor

    Directory of Open Access Journals (Sweden)

    Ippili Kaushal

    2009-01-01

    Full Text Available Olfactory ensheathing cells (OECs are found in the olfactory bulb and olfactory nasal mucosa. They resemble Schwann cells on light and electron microscopy, however, immunohistochemical staining can distinguish between the two. There are less than 30 cases of olfactory groove schwannomas reported in the literature while there is only one reported case of OEC tumor. We report an OEC tumor in a 42-year-old male and discuss the pathology and origin of this rare tumor.

  8. Development of cardiac parasympathetic neurons, glial cells, and regional cholinergic innervation of the mouse heart.

    Science.gov (United States)

    Fregoso, S P; Hoover, D B

    2012-09-27

    Very little is known about the development of cardiac parasympathetic ganglia and cholinergic innervation of the mouse heart. Accordingly, we evaluated the growth of cholinergic neurons and nerve fibers in mouse hearts from embryonic day 18.5 (E18.5) through postnatal day 21(P21). Cholinergic perikarya and varicose nerve fibers were identified in paraffin sections immunostained for the vesicular acetylcholine transporter (VAChT). Satellite cells and Schwann cells in adjacent sections were identified by immunostaining for S100β calcium binding protein (S100) and brain-fatty acid binding protein (B-FABP). We found that cardiac ganglia had formed in close association to the atria and cholinergic innervation of the atrioventricular junction had already begun by E18.5. However, most cholinergic innervation of the heart, including the sinoatrial node, developed postnatally (P0.5-P21) along with a doubling of the cross-sectional area of cholinergic perikarya. Satellite cells were present throughout neonatal cardiac ganglia and expressed primarily B-FABP. As they became more mature at P21, satellite cells stained strongly for both B-FABP and S100. Satellite cells appeared to surround most cardiac parasympathetic neurons, even in neonatal hearts. Mature Schwann cells, identified by morphology and strong staining for S100, were already present at E18.5 in atrial regions that receive cholinergic innervation at later developmental times. The abundance and distribution of S100-positive Schwann cells increased postnatally along with nerve density. While S100 staining of cardiac Schwann cells was maintained in P21 and older mice, Schwann cells did not show B-FABP staining at these times. Parallel development of satellite cells and cholinergic perikarya in the cardiac ganglia and the increase in abundance of Schwann cells and varicose cholinergic nerve fibers in the atria suggest that neuronal-glial interactions could be important for development of the parasympathetic nervous

  9. Human periodontal ligament stem cells repair mental nerve injury*

    Institute of Scientific and Technical Information of China (English)

    Bohan Li; Hun-Jong Jung; Soung-Min Kim; Myung-Jin Kim; Jeong Won Jahng; Jong-Ho Lee

    2013-01-01

    Human periodontal ligament stem cells are easily accessible and can differentiate into Schwann cells. We hypothesized that human periodontal ligament stem cells can be used as an alternative source for the autologous Schwann cells in promoting the regeneration of injured peripheral nerve. To validate this hypothesis, human periodontal ligament stem cells (1 × 106) were injected into the crush-injured left mental nerve in rats. Simultaneously, autologous Schwann cells (1 × 106) and PBS were also injected as controls. Real-time reverse transcriptase polymerase chain reaction showed that at 5 days after injection, mRNA expression of low affinity nerve growth factor receptor was sig-nificantaly increased in the left trigeminal ganglion of rats with mental nerve injury. Sensory tests, histomorphometric evaluation and retrograde labeling demonstrated that at 2 and 4 weeks after in-jection, sensory function was significantly improved, the numbers of retrograde labeled sensory neurons and myelinated axons were significantly increased, and human periodontal ligament stem cells and autologous Schwann cells exhibited similar therapeutic effects. These findings suggest that transplantation of human periodontal ligament stem cells show a potential value in repair of mental nerve injury.

  10. Premigratory and migratory neural crest cells are multipotent in vivo

    NARCIS (Netherlands)

    Baggiolini, Arianna; Varum, Sandra; Mateos, José María; Bettosini, Damiano; John, Nessy; Bonalli, Mario; Ziegler, Urs; Dimou, Leda; Clevers, Hans; Furrer, Reinhard; Sommer, Lukas

    2015-01-01

    The neural crest (NC) is an embryonic stem/progenitor cell population that generates a diverse array of cell lineages, including peripheral neurons, myelinating Schwann cells, and melanocytes, among others. However, there is a long-standing controversy as to whether this broad developmental

  11. Premigratory and migratory neural crest cells are multipotent in vivo

    NARCIS (Netherlands)

    Baggiolini, Arianna; Varum, Sandra; Mateos, José María; Bettosini, Damiano; John, Nessy; Bonalli, Mario; Ziegler, Urs; Dimou, Leda; Clevers, Hans; Furrer, Reinhard; Sommer, Lukas

    2015-01-01

    The neural crest (NC) is an embryonic stem/progenitor cell population that generates a diverse array of cell lineages, including peripheral neurons, myelinating Schwann cells, and melanocytes, among others. However, there is a long-standing controversy as to whether this broad developmental perspect

  12. Undifferentiated and differentiated adipose-derived stem cells improve nerve regeneration in a rat model of facial nerve defect.

    Science.gov (United States)

    Watanabe, Yorikatsu; Sasaki, Ryo; Matsumine, Hajime; Yamato, Masayuki; Okano, Teruo

    2017-02-01

    Autologous nerve grafting is the current procedure used for repairing facial nerve gaps. As an alternative to this method, tissue engineering cell-based therapy using induced pluripotent stem cells, Schwann cells and bone marrow-derived mesenchymal stem cells has been proposed. However, these cells have major problems, including tumorigenesis in induced pluripotent stem cells and invasiveness and limited tissue associated with harvesting for the other cells. Here, we investigated the therapeutic potential of adipose-derived stem cells (ASCs), which can be harvested easily and repeatedly by a minimally invasive liposuction procedure. The ASCs had characteristics of mesenchymal tissue lineages and could differentiate into Schwann-like cells that were relatively simple to isolate and expand in culture. In an in vivo study, a silicone conduit containing undifferentiated ASCs, differentiated ASCs or Schwann cells were transplanted, embedded in a collagen gel and the efficacy of repair of a 7 mm-gap in the rat facial nerve examined. Morphometric quantification analysis of regenerated facial nerves after a regeneration period of 13 weeks showed that undifferentiated ASCs, differentiated ASCs, and Schwann cells had similar potential for nerve regeneration. Furthermore, the functional recovery of facial nerve regeneration using a rat facial palsy scoring system in the three groups was close to that in autologous nerve graft positive controls. These findings suggest that undifferentiated and differentiated ASCs may both have therapeutic potential in facial nerve regeneration as a source of Schwann cells in cell-based therapy performed as an alternative to autologous nerve grafts. Copyright © 2014 John Wiley & Sons, Ltd. Copyright © 2014 John Wiley & Sons, Ltd.

  13. Propofol promotes spinal cord injury repair by bone marrow mesenchymal stem cell transplantation

    Directory of Open Access Journals (Sweden)

    Ya-jing Zhou

    2015-01-01

    Full Text Available Propofol is a neuroprotective anesthetic. Whether propofol can promote spinal cord injury repair by bone marrow mesenchymal stem cells remains poorly understood. We used rats to investigate spinal cord injury repair using bone marrow mesenchymal stem cell transplantation combined with propofol administration via the tail vein. Rat spinal cord injury was clearly alleviated; a large number of newborn non-myelinated and myelinated nerve fibers appeared in the spinal cord, the numbers of CM-Dil-labeled bone marrow mesenchymal stem cells and fluorogold-labeled nerve fibers were increased and hindlimb motor function of spinal cord-injured rats was markedly improved. These improvements were more prominent in rats subjected to bone marrow mesenchymal cell transplantation combined with propofol administration than in rats receiving monotherapy. These results indicate that propofol can enhance the therapeutic effects of bone marrow mesenchymal stem cell transplantation on spinal cord injury in rats.

  14. Propofol promotes spinal cord injury repair by bone marrow mesenchymal stem cell transplantation

    Institute of Scientific and Technical Information of China (English)

    Ya-jing Zhou; Jian-min Liu; Shu-ming Wei; Yun-hao Zhang; Zhen-hua Qu; Shu-bo Chen

    2015-01-01

    Propofol is a neuroprotective anesthetic. Whether propofol can promote spinal cord injury repair by bone marrow mesenchymal stem cells remains poorly understood. We used rats to investigate spinal cord injury repair using bone marrow mesenchymal stem cell transplantation combined with propofol administrationvia the tail vein. Rat spinal cord injury was clearly alleviated; a large number of newborn non-myelinated and myelinated nerve ifbers appeared in the spinal cord, the numbers of CM-Dil-labeled bone marrow mesenchymal stem cells and lfuorogold-labeled nerve ifbers were increased and hindlimb motor function of spinal cord-injured rats was mark-edly improved. These improvements were more prominent in rats subjected to bone marrow mesenchymal cell transplantation combined with propofol administration than in rats receiving monotherapy. These results indicate that propofol can enhance the therapeutic effects of bone marrow mesenchymal stem cell transplantation on spinal cord injury in rats.

  15. Expression of polysialylated neural cell adhesion molecules on adult stem cells after neuronal differentiation of inner ear spiral ganglion neurons

    Energy Technology Data Exchange (ETDEWEB)

    Park, Kyoung Ho [Department of Otolaryngology Head and Neck Surgery, College of Medicine, Catholic University, Seoul (Korea, Republic of); Yeo, Sang Won, E-mail: swyeo@catholic.ac.kr [Department of Otolaryngology Head and Neck Surgery, College of Medicine, Catholic University, Seoul (Korea, Republic of); Troy, Frederic A., E-mail: fatroy@ucdavis.edu [Department of Biochemistry and Molecular Medicine, University of California, School of Medicine, Davis, CA 95616 (United States); Xiamen University, School of Medicine, Xiamen City (China)

    2014-10-17

    Highlights: • PolySia expressed on neurons primarily during early stages of neuronal development. • PolySia–NCAM is expressed on neural stem cells from adult guinea pig spiral ganglion. • PolySia is a biomarker that modulates neuronal differentiation in inner ear stem cells. - Abstract: During brain development, polysialylated (polySia) neural cell adhesion molecules (polySia–NCAMs) modulate cell–cell adhesive interactions involved in synaptogenesis, neural plasticity, myelination, and neural stem cell (NSC) proliferation and differentiation. Our findings show that polySia–NCAM is expressed on NSC isolated from adult guinea pig spiral ganglion (GPSG), and in neurons and Schwann cells after differentiation of the NSC with epidermal, glia, fibroblast growth factors (GFs) and neurotrophins. These differentiated cells were immunoreactive with mAb’s to polySia, NCAM, β-III tubulin, nestin, S-100 and stained with BrdU. NSC could regenerate and be differentiated into neurons and Schwann cells. We conclude: (1) polySia is expressed on NSC isolated from adult GPSG and on neurons and Schwann cells differentiated from these NSC; (2) polySia is expressed on neurons primarily during the early stage of neuronal development and is expressed on Schwann cells at points of cell–cell contact; (3) polySia is a functional biomarker that modulates neuronal differentiation in inner ear stem cells. These new findings suggest that replacement of defective cells in the inner ear of hearing impaired patients using adult spiral ganglion neurons may offer potential hope to improve the quality of life for patients with auditory dysfunction and impaired hearing disorders.

  16. Demonstration of S-100 protein in sustentacular cells of phaeochromocytomas and paragangliomas

    DEFF Research Database (Denmark)

    Schroder, H D; Johannsen, L

    1986-01-01

    Eighteen phaeochromocytomas, including both sporadic and familial cases, four cervical paragangliomas, two jugular paragangliomas, and one abdominal paraganglioma were examined immunohistochemically for the presence of S-100 protein. Positive staining in cells morphologically similar...... protein further supporting their Schwann cell relationship. The number of S-100 positive cells varied considerably. They demonstrated a spindle celled or elongated configuration with long slender processes. The nature of the sustentacular cell proliferation, neoplastic versus reactive, is discussed....

  17. Glial cell transplants that are subsequently rejected can be used to influence regeneration of glial cell environments in the CNS.

    Science.gov (United States)

    Blakemore, W F; Crang, A J; Franklin, R J; Tang, K; Ryder, S

    1995-02-01

    Transplantation of glial cells into demyelinating lesions in CNS offers an experimental approach which allows investigation of the complex interactions that occur between CNS glia, Schwann cells, and axons during remyelination and repair. Earlier studies have shown that 1) transplanted astrocytes are able to prevent Schwann cells from participating in CNS remyelination, but that they are only able to do so with the cooperation of cells of the oligodendrocyte lineage, and 2) transplanted mouse oligodendrocytes can remyelinate rat axons provided their rejection is controlled by immunosuppression. On the basis of these observations, we have been able to prevent the Schwann cell remyelination that normally follows ethidium bromide demyelination in the rat spinal cord by co-transplanting isogeneic astrocytes with a potentially rejectable population of mouse oligodendrocyte lineage cells. Since male mouse cells were used it was possible to demonstrate their presence in immunosuppressed recipients using a mouse Y-chromosome probe by in situ hydridisation. When myelinating mouse cells were rejected by removal of immunosuppression, the demyelinated axons were remyelinated by host oligodendrocytes rather than Schwann cells, whose entry was prevented by the persistence of the transplanted isogeneic astrocytes. The oligodendrocyte remyelination was extensive and rapid, indicating that the inflammation associated with cell rejection did not impede repair. If this host oligodendrocyte remyelination was prevented by local X-irradiation, the lesion consisted of demyelinated axons surrounded by processes from the transplanted astrocytes. By this approach, it was possible to create an environment which resembled the chronic plaques of multiple sclerosis. Thus, these experiments demonstrate that in appropriate circumstances the temporary presence of a population of glial cells can alter the outcome of damage to the CNS.

  18. Isolation and differentiation of neural stem/progenitor cells from fetal rat dorsal root ganglia

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    To find a promising alternative to neurons or schwann cells (SCs) for peripheral nerve repair applications,this study sought to isolate stem cells from fetal rat dorsal root ganglion (DRG) explants.Molecular expression analysis confirmed neural stem cell characteristics of DRG-derived neurospheres in terms of expressing neural stem cell-specific genes and a set of well-defined genes related to stem cell niches and glial fate decision.Under the influence of neurotrophic factors,bFGF and NGF,the neurospheres gave rise to neurofilament-expressing neurons and S100-expressing Schwann cell-like cells by different pathways.This study suggests that a subpopulation of stem cells that reside in DRGs is the progenitor of neurons and glia,which could directly induce the differentiation toward neurons,or SCs.

  19. Origin and Regenerative Potential of Vertebrate Mechanoreceptor-Associated Stem Cells

    Directory of Open Access Journals (Sweden)

    Darius Widera

    2012-01-01

    Full Text Available Meissner corpuscles and Merkel cell neurite complexes are highly specialized mechanoreceptors present in the hairy and glabrous skin, as well as in different types of mucosa. Several reports suggest that after injury, such as after nerve crush, freeze injury, or dissection of the nerve, they are able to regenerate, particularly including reinnervation and repopulation of the mechanoreceptors by Schwann cells. However, little is known about mammalian cells responsible for these regenerative processes. Here we review cellular origin of this plasticity in the light of newly described adult neural crest-derived stem cell populations. We also discuss further potential multipotent stem cell populations with the ability to regenerate disrupted innervation and to functionally recover the mechanoreceptors. These capabilities are discussed as in context to cellularly reprogrammed Schwann cells and tissue resident adult mesenchymal stem cells.

  20. A study on peripheral nerve regeneration via biomimetic conduits loaded with Schwann cells and nerve growth factor

    Institute of Scientific and Technical Information of China (English)

    ZHAO Fengyi; ZHOU Peilan; WANG Ruilin; YANG Mingfu; ZHAO Weisheng; WEI Dian; ZHANG Tieliang; YAO Kangde; CUI Yuanlu

    2001-01-01

    @@ Guided tissue regeneration is a new approach in the reconstructive surgery of peripheral nerves. Biomimetic conducts were construct from the expanded vein onwhose inner surface composited with amnion filaments (cf. Fig 1).

  1. Autoantibodies to Non-myelin Antigens as Contributors to the Pathogenesis of Multiple Sclerosis

    OpenAIRE

    2013-01-01

    For years, investigators have sought to prove that myelin antigens are the primary targets of autoimmunity in multiple sclerosis (MS). Recent experiments have begun to challenge this assumption, particularly when studying the neurodegenerative phase of MS. T-lymphocyte responses to myelin antigens have been extensively studied, and are likely early contributors to the pathogenesis of MS. Antibodies to myelin antigens have a much more inconstant association with the pathogenesis of MS. Recent ...

  2. Ganglion cell like cells, diagnostic dilemma

    Directory of Open Access Journals (Sweden)

    Anand Shankar Ammanagi

    2013-01-01

    Full Text Available We report a case of cutaneous swelling found on the left anterior axillary fold of a 41-year-old man. Gross examination of specimen excised from the dermis showed a well-circumscribed nodule histologically composed of spindle cells with interspersed ganglion cell like cells. On hematoxylin and eosine (H and E staining it was diagnosed as ganglioneuroma. Ganglioneuromas are rare, benign, fully differentiated tumors that contain mature schwann cells, ganglion cells, fibrous tissue, and nerve fibers. They are commonly found along the paravertebral sympathetic ganglia and sometimes in the adrenal medulla. However primary cutaneous ganglioneuroma is an extremely rare tumor. Immunohistochemical workup revealed a fibroblastic origin and hence the case was diagnosed as fibromatosis with ganglion cell like fibroblasts. This case report suggests that the features considered diagnostic of ganglioneuromas can occur in other cutaneous lesions and, therefore, this diagnosis cannot be offered only on the basis of H and E.

  3. Stem Cell Transplantation for Peripheral Nerve Regeneration: Current Options and Opportunities

    Directory of Open Access Journals (Sweden)

    Liangfu Jiang

    2017-01-01

    Full Text Available Peripheral nerve regeneration is a complicated process highlighted by Wallerian degeneration, axonal sprouting, and remyelination. Schwann cells play an integral role in multiple facets of nerve regeneration but obtaining Schwann cells for cell-based therapy is limited by the invasive nature of harvesting and donor site morbidity. Stem cell transplantation for peripheral nerve regeneration offers an alternative cell-based therapy with several regenerative benefits. Stem cells have the potential to differentiate into Schwann-like cells that recruit macrophages for removal of cellular debris. They also can secrete neurotrophic factors to promote axonal growth, and remyelination. Currently, various types of stem cell sources are being investigated for their application to peripheral nerve regeneration. This review highlights studies involving the stem cell types, the mechanisms of their action, methods of delivery to the injury site, and relevant pre-clinical or clinical data. The purpose of this article is to review the current point of view on the application of stem cell based strategy for peripheral nerve regeneration.

  4. Stem Cell Transplantation for Peripheral Nerve Regeneration: Current Options and Opportunities.

    Science.gov (United States)

    Jiang, Liangfu; Jones, Salazar; Jia, Xiaofeng

    2017-01-05

    Peripheral nerve regeneration is a complicated process highlighted by Wallerian degeneration, axonal sprouting, and remyelination. Schwann cells play an integral role in multiple facets of nerve regeneration but obtaining Schwann cells for cell-based therapy is limited by the invasive nature of harvesting and donor site morbidity. Stem cell transplantation for peripheral nerve regeneration offers an alternative cell-based therapy with several regenerative benefits. Stem cells have the potential to differentiate into Schwann-like cells that recruit macrophages for removal of cellular debris. They also can secrete neurotrophic factors to promote axonal growth, and remyelination. Currently, various types of stem cell sources are being investigated for their application to peripheral nerve regeneration. This review highlights studies involving the stem cell types, the mechanisms of their action, methods of delivery to the injury site, and relevant pre-clinical or clinical data. The purpose of this article is to review the current point of view on the application of stem cell based strategy for peripheral nerve regeneration.

  5. Evolution of the cell theory.

    Science.gov (United States)

    Wolpert, L

    1995-09-29

    The problem of the nature of life has a long history going back to the Greeks. There was little real progress until the 19th century and Aristotle may have been at home with many 18th century ideas about vital forces and basic units. Although Hooke described cells in 1665 it took a further 200 years for the significance and nature of cells to be appreciated. In the mid 18th century some considered the basic building blocks of living matter to be fibrous. Globular theories, the precursor to the cell theory, were quite popular at the beginning of the 19th century. Many workers, as microscopes improved, had described various cell types and structures including the nucleus but the idea that cells were the universal units is associated with in 1838 and that of Schwann in 1839. However, Schwann mistakenly thought that cells could form de novo. Cell division was established by Remak and others in the 1850s. Mitosis was first understood by Flemming in 1882. The existence of the animal cell membrane was only established by the beautiful experiments of Overton in 1895. The history of the cell theory can be used to show that progress can be based on incorrect but productive ideas. It is one of the most important ideas in all of biology.

  6. Combining Gene and Stem Cell Therapy for Peripheral Nerve Tissue Engineering.

    Science.gov (United States)

    Busuttil, Francesca; Rahim, Ahad A; Phillips, James B

    2017-02-15

    Despite a substantially increased understanding of neuropathophysiology, insufficient functional recovery after peripheral nerve injury remains a significant clinical challenge. Nerve regeneration following injury is dependent on Schwann cells, the supporting cells in the peripheral nervous system. Following nerve injury, Schwann cells adopt a proregenerative phenotype, which supports and guides regenerating nerves. However, this phenotype may not persist long enough to ensure functional recovery. Tissue-engineered nerve repair devices containing therapeutic cells that maintain the appropriate phenotype may help enhance nerve regeneration. The combination of gene and cell therapy is an emerging experimental strategy that seeks to provide the optimal environment for axonal regeneration and reestablishment of functional circuits. This review aims to summarize current preclinical evidence with potential for future translation from bench to bedside.

  7. Calcium signalling in sensory neurones and peripheral glia in the context of diabetic neuropathies.

    Science.gov (United States)

    Verkhratsky, Alexei; Fernyhough, Paul

    2014-11-01

    Peripheral sensory nervous system is comprised of neurones with their axons and neuroglia that includes satellite glial cells in sensory ganglia, myelinating, non-myelinating and perisynaptic Schwann cells. Pathogenesis of peripheral diabetic polyneuropathies is associated with aberrant function of both neurones and glia. Deregulated Ca(2+) homoeostasis and aberrant Ca(2+) signalling in neuronal and glial elements contributes to many forms of neuropathology and is fundamental to neurodegenerative diseases. In diabetes both neurones and glia experience metabolic stress and mitochondrial dysfunction which lead to deregulation of Ca(2+) homeostasis and Ca(2+) signalling, which in their turn lead to pathological cellular reactions contributing to development of diabetic neuropathies. Molecular cascades responsible for Ca(2+) homeostasis and signalling, therefore, can be regarded as potential therapeutic targets. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Points regarding cell transplantation for the treatment of spinal cord injur y

    Institute of Scientific and Technical Information of China (English)

    Chizuka Ide; Kenji Kanekiyo

    2016-01-01

    Transplantation of somatic cells, including bone marrow stromal cells (BMSCs), bone marrow mononu-clear cells (BMNCs), and choroid plexus epithelial cells (CPECs), enhances the outgrowth of regenerating axons and promotes locomotor improvements. They are not integrated into the host spinal cord, but disappear within 2-3 weeks after transplantation. Regenerating axons extend at the spinal cord lesion through the astrocyte-devoid area that is iflled with connective tissue matrices. Regenerating axons have characteristics of peripheral nerves:they are associated with Schwann cells, and embedded in connective tissue matrices. It has been suggested that neurotrophic factors secreted from BMSCs and CPECs promote“intrinsic”ability of the spinal cord to regenerate. Transplanted Schwann cells survive long-term, and are integrated into the host spinal cord, serving as an effective scaffold for the outgrowth of regenerating axons in the spinal cord. The disadvantage that axons are blocked to extend through the glial scar at the border of the lesion is overcome. Schwann cells have been approved for clinical applications. Neural stem/progenitor cells (NSPCs) survive long-term, proliferate, and differentiate into glial cells and/or neurons after trans-plantation. No method is available at present to manipulate and control the behaviors of NPSCs to allow them to appropriately integrate into the host spinal cord. NPSP transplantation is not necessarily effective for locomotor improvement.

  9. Points regarding cell transplantation for the treatment of spinal cord injury

    Directory of Open Access Journals (Sweden)

    Chizuka Ide

    2016-01-01

    Full Text Available Transplantation of somatic cells, including bone marrow stromal cells (BMSCs, bone marrow mononuclear cells (BMNCs, and choroid plexus epithelial cells (CPECs, enhances the outgrowth of regenerating axons and promotes locomotor improvements. They are not integrated into the host spinal cord, but disappear within 2-3 weeks after transplantation. Regenerating axons extend at the spinal cord lesion through the astrocyte-devoid area that is filled with connective tissue matrices. Regenerating axons have characteristics of peripheral nerves: they are associated with Schwann cells, and embedded in connective tissue matrices. It has been suggested that neurotrophic factors secreted from BMSCs and CPECs promote “intrinsic” ability of the spinal cord to regenerate. Transplanted Schwann cells survive long-term, and are integrated into the host spinal cord, serving as an effective scaffold for the outgrowth of regenerating axons in the spinal cord. The disadvantage that axons are blocked to extend through the glial scar at the border of the lesion is overcome. Schwann cells have been approved for clinical applications. Neural stem/progenitor cells (NSPCs survive long-term, proliferate, and differentiate into glial cells and/or neurons after transplantation. No method is available at present to manipulate and control the behaviors of NPSCs to allow them to appropriately integrate into the host spinal cord. NPSP transplantation is not necessarily effective for locomotor improvement.

  10. Differentiation of Rat Neural Stem Cells and Its Relationship With Environment

    Institute of Scientific and Technical Information of China (English)

    YI-HUA AN; HONG-YUN WANG; ZHI-XIAN GAO; ZHONG-CHENG WANG

    2004-01-01

    Objective To explore the differentiation fates of rat neural stem cells (NSCs) in differenten vironmental conditions. Methods NSCs derived from 16-day-old rat embryo were proliferated in vitro and implanted into the brain of rats with intra-cerebral hemorrhage. At the same time some NSCs were co-culturedin vitro with Schwann cells derived from newborn rats. MAP-2, GFAP and Ga1C (which are the specific markers of neural cells, astrocytes and oligodendrocytes respectively),BrdU and β-tubulin were detected by immunohistochemical and immunofluorescent methods.Results BrdU positive cells that were implanted into the brain distributed around the hemorrhagic area. The majority of them were GFAP positive astrocytes while a few of them were β-tubulin positive neural cells or GalC positive oligodendrocytes. After being co-cultured with Schwann cellsin vitro,NSCs are predominately shown β-tubulin and MAP-2 positive, and only a minority of them were GFAP or GalC positive. Conclusions The hemorrhagic environment in vivo induces NSCs to differentiate mainly into astrocytes while co-culture with Schwann cells in vitro induce the majority of NSCs to differentiate into neural cells.

  11. Recombinant spider silk with cell binding motifs for specific adherence of cells.

    Science.gov (United States)

    Widhe, Mona; Johansson, Ulrika; Hillerdahl, Carl-Olof; Hedhammar, My

    2013-11-01

    Silk matrices have previously been shown to possess general properties governing cell viability. However, many cell types also require specific adhesion sites for successful in vitro culture. Herein, we have shown that cell binding motifs can be genetically fused to a partial spider silk protein, 4RepCT, without affecting its ability to self-assemble into stable matrices directly in a physiological-like buffer. The incorporated motifs were exposed in the formed matrices, and available for binding of integrins. Four different human primary cell types; fibroblasts, keratinocytes, endothelial cells and Schwann cells, were applied to the matrices and investigated under serum-free culture conditions. Silk matrices with cell binding motifs, especially RGD, were shown to promote early adherence of cells, which formed stress fibers and distinct focal adhesion points. Schwann cells acquired most spread-out morphology on silk matrices with IKVAV, where significantly more viable cells were found, also when compared to wells coated with laminin. This strategy is thus suitable for development of matrices that allow screening of various cell binding motifs and their effect on different cell types. © 2013 Elsevier Ltd. All rights reserved.

  12. GRANULAR CELL TUMOR OF BREAST (CYTOLOGICAL DIAGNOSIS CONFIRMED BY HISTOPATHOLOGY

    Directory of Open Access Journals (Sweden)

    Divvya

    2014-10-01

    Full Text Available Granular cell tumor is a tumor derived from Schwann cells of peripheral nerves and it can occur throughout the body. About 5% of granular cell tumors occur in breast and are mostly benign in nature. We report a case of 30 year old female who presented with a swelling in right breast which on histo pathological examination revealed features consistent with granular cell tumor. This case is highlighted to reveal the importance of histopathology in differentiating granular cell tumor from carcinoma breast which is difficult based on clinical, radiological and cytological examination alone.

  13. Obtención, cultivo y caracterización de células de Schwann: un modelo de terapia celular

    Directory of Open Access Journals (Sweden)

    Clara Spinel

    2000-02-01

    Full Text Available

    Numerosos estudios han demostrado que las células de Schwann son importantes para la regeneración del sistema nervioso. Esta célula produce una serie de moléculas que favorecen el crecimiento de las fibras nerviosas. Estas moléculas pueden ser solubles como el NGF (Factor de crecimiento Nervioso, el LIF (Factor Inhibidor de la Leucemia, el BDNF (factor de crecimiento derivado del cerebro y otros factores de crecimiento o moléculas asociadas con la adhesión celular como N-CAM (Molécula de Adhesión Neuronal, L1 y a la matriz extracelular, especialmente a la lámina basal como el complejo proteoglicano-laminina. Estas características han permitido a los investigadores utilizar estas células para estimular la regeneración, tanto del sistema nervioso central (SNC como del sistema nervioso periférico (SNP.

    Dentro de la línea de investigación de regeneración y del sistema nervioso del Laboratorio de Neurociencias del Instituto Nacional de Salud, se han obtenido, cultivado y caracterizado células de Schwann de ratón, rata y humano adultos, con el fin de desarrollar prótesis celulares que podrían soportar la regeneración. En este trabajo se muestran resultados obtenidos en el proceso de obtención, cultivo y caracterización de estas células.

    La obtención, el cultivo y la caracterización se han realizado por diferentes metodologías. Para la obtención, hemos usado y estandarizado el cultivo a partir de dos fuentes de células, nervio periférico y ganglio tanto sensorial en el caso de ratón, como autonómico en el caso de células humanas. Estas técnicas nos han permitido obtener cultivos altamente enriquecidos en células de Schwann que en ratón alcanzan el 90%, en rata el 85% y en humano entre el 70

  14. Entropy measures of collective cell migration

    Science.gov (United States)

    Whitby, Ariadne; Parrinello, Simona; Faisal, Aldo

    2015-03-01

    Collective cell migration is a critical process during tissue formation and repair. To this end there is a need to develop tools to quantitatively measure the dynamics of collective cell migration obtained from microscopy data. Drawing on statistical physics we use entropy of velocity fields derived from dense optic flow to quantitatively measure collective migration. Using peripheral nerve repair after injury as experimental system, we study how Schwann cells, guided by fibroblasts, migrate in cord-like structures across the cut, paving a highway for neurons. This process of emergence of organised behaviour is key for successful repair, yet the emergence of leader cells and transition from a random to ordered state is not understood. We find fibroblasts induce correlated directionality in migrating Schwann cells as measured by a decrease in the entropy of motion vector. We show our method is robust with respect to image resolution in time and space, giving a principled assessment of how various molecular mechanisms affect macroscopic features of collective cell migration. Finally, the generality of our method allows us to process both simulated cell movement and microscopic data, enabling principled fitting and comparison of in silico to in vitro. ICCS, Imperial College London & MRC Clinical Sciences Centre.

  15. The discovery of oligodendroglia cells by Rio-Hortega: his original articles. 1921.

    Science.gov (United States)

    Iglesias-Rozas, José R; Garrosa, Manuel

    2012-01-01

    Comment on: del Río-Hortega P. Glia with very few processes (oligodendroglia). Clin Neuropathol. 2012; 31: 440-459, originally published in Archivos de Neurobiología. 1921; 2: 16-43 and del Río-Hortega P. Are the glia with very few processes homologous with Schwann cells? Clin Neuropathol. 2012; 31: 460-462, originally published in Bol de la Soc Esp de Biol. 1922; X: 25-28.

  16. Amine-functionalized polypyrrole: Inherently cell adhesive conducting polymer.

    Science.gov (United States)

    Lee, Jae Y; Schmidt, Christine E

    2015-06-01

    Electrically conducting polymers (CPs) have been recognized as novel biomaterials that can electrically communicate with biological systems. For their tissue engineering applications, CPs have been modified to promote cell adhesion for improved interactions between biomaterials and cells/tissues. Conventional approaches to improve cell adhesion involve the surface modification of CPs with biomolecules, such as physical adsorption of cell adhesive proteins and polycationic polymers, or their chemical immobilization; however, these approaches require additional multiple modification steps with expensive biomolecules. In this study, as a simple and effective alternative to such additional biomolecule treatment, we synthesized amine-functionalized polypyrrole (APPy) that inherently presents cell adhesion-supporting positive charges under physiological conditions. The synthesized APPy provides electrical activity in a moderate range and a hydrophilic surface compared to regular polypyrrole (PPy) homopolymers. Under both serum and serum-free conditions, APPy exhibited superior attachment of human dermal fibroblasts and Schwann cells compared to PPy homopolymer controls. Moreover, Schwann cell adhesion onto the APPy copolymer was at least similar to that on poly-l-lysine treated PPy controls. Our results indicate that amine-functionalized CP substrates will be useful to achieve good cell adhesion and potentially electrically stimulate various cells. In addition, amine functionality present on CPs can further serve as a novel and flexible platform to chemically tether various bioactive molecules, such as growth factors, antibodies, and chemical drugs. © 2014 Wiley Periodicals, Inc.

  17. Cultivo purificado de células de Schwann provenientes de ganglios de la raíz dorsal de Ratón adulto

    Directory of Open Access Journals (Sweden)

    Spinel Clara M.

    2006-06-01

    Full Text Available Las células de Schwann (CS son la glía del sistema nervioso periférico. Se encargan de apoyar la función
    neuronal y ayudan a la conducción del impulso nervioso. Estas células juegan un papel muy importante en el
    crecimiento axonal, no solo durante el desarrollo embrional sino durante los procesos de regeneración nerviosa. Las CS secretan un gran número de factores que promueven la regeneración y esto las ha convertido en blanco para el diseño de prótesis artificiales. Para estos estudios es necesario establecer cultivos enriquecidos de CS los cuales son realizados en general a partir de nervios periféricos, sin embargo, ciertos estudios muestran a los ganglios de la raíz dorsal (GRD como una buena fuente para la obtención de estas células. En este estudio se estableció un protocolo para la obtención de CS a partir de GRD de ratones adultos. Mediante técnicas de descapsulación, disociación enzimática y disociación mecánica fue posible establecer cultivos de CS con una pureza del 98%. Los cultivos fueron realizados sobre plástico sin afectar esto la pureza de los mismos. Este protocolo permitió la obtención de grandes poblaciones de CS (3 x 106 células/animal en tan solo un mes. Estos resultados mejoran las perspectivas del uso de los GRD como fuente para la obtención de este tipo celular.

  18. Secretion of nerve growth factor, brain-derived neurotrophic factor, and glial cell-line derived neurotrophic factor in co-culture of four cell types in cerebrospinal fluid-containing medium

    Institute of Scientific and Technical Information of China (English)

    Sanjiang Feng; Minghua Zhuang; Rui Wu

    2012-01-01

    The present study co-cultured human embryonic olfactory ensheathing cells, human Schwann cells, human amniotic epithelial cells and human vascular endothelial cells in complete culture medium- containing cerebrospinal fluid. Enzyme linked immunosorbent assay was used to detect nerve growth factor, brain-derived neurotrophic factor, and glial cell line-derived neurotrophic factor secretion in the supernatant of co-cultured cells. Results showed that the number of all cell types reached a peak at 7–10 days, and the expression of nerve growth factor, brain-derived neurotrophic factor, and glial cell line-derived neurotrophic factor peaked at 9 days. Levels of secreted nerve growth factor were four-fold higher than brain-derived neurotrophic factor, which was three-fold higher than glial cell line-derived neurotrophic factor. Increasing concentrations of cerebrospinal fluid (10%, 20% and 30%) in the growth medium caused a decrease of neurotrophic factor secretion. Results indicated co-culture of human embryonic olfactory ensheathing cells, human Schwann cells, human amniotic epithelial cells and human vascular endothelial cells improved the expression of nerve growth factor, brain-derived neurotrophic factor, and glial cell line-derived neurotrophic factor. The reduction of cerebrospinal fluid extravasation at the transplant site after spinal cord injury is beneficial for the survival and secretion of neurotrophic factors from transplanted cells.

  19. Gene expression profiling studies in regenerating nerves in a mouse model for CMT1X: uninjured Cx32-knockout peripheral nerves display expression profile of injured wild type nerves.

    Science.gov (United States)

    Freidin, Mona; Asche-Godin, Samantha; Abrams, Charles K

    2015-01-01

    X-linked Charcot-Marie-Tooth disease (CMT1X) is an inherited peripheral neuropathy caused by mutations in GJB1, the human gene for Connexin32 (Cx32). This present study uses Ilumina Ref8-v2 BeadArray to examine the expression profiles of injured and uninjured sciatic nerves at 5, 7, and 14 days post-crush injury (dpi) from Wild Type (WT) and Cx32-knockout (Cx32KO) mice to identify the genes and signaling pathways that are dysregulated in the absence of Schwann cell Cx32. Given the assumption that loss of Schwann cell Cx32 disrupts the regeneration and maintenance of myelinated nerve leading to a demyelinating neuropathy in CMT1X, we initially hypothesized that nerve crush injury would result in significant increases in differential gene expression in Cx32KO mice relative to WT nerves. However, microarray analysis revealed a striking collapse in the number of differentially expressed genes at 5 and 7 dpi in Cx32KO nerves relative to WT, while uninjured and 14 dpi time points showed large numbers of differentially regulated genes. Further comparisons within each genotype showed limited changes in Cx32KO gene expression following crush injury when compared to uninjured Cx32KO nerves. By contrast, WT nerves exhibited robust changes in gene expression at 5 and 7 dpi with no significant differences in gene expression by 14dpi relative to uninjured WT nerve samples. Taken together, these data suggest that the gene expression profile in uninjured Cx32KO sciatic nerve strongly resembles that of a WT nerve following injury and that loss of Schwann cell Cx32 leads to a basal state of gene expression similar to that of an injured WT nerve. These findings support a role for Cx32 in non-myelinating and regenerating populations of Schwann cells in normal axonal maintenance in re-myelination, and regeneration of peripheral nerve following injury. Disruption of Schwann cell-axonal communication in CMT1X may cause dysregulation of signaling pathways that are essential for the

  20. Biocompatibility evaluation of electrospun aligned poly(propylene carbonate) nanofibrous scaffolds with peripheral nerve tissues and cells in vitro

    Institute of Scientific and Technical Information of China (English)

    WANG Yu; ZHAO Zhe; ZHAO Bin; QI Hong-xu; PENG Jiang; ZHANG Li; XU Wen-jing; HU Ping; LU Shi-bi

    2011-01-01

    Background Peripheral nerve regeneration across large gaps is clinically challenging. Scaffold design plays a pivotal role in nerve tissue engineering. Recently, nanofibrous scaffolds have proven a suitable environment for cell attachment and proliferation due to similarities of their physical properties to natural extracellular matrix. Poly(propylene carbonate)(PPC) nanofibrous scaffolds have been investigated for vascular tissue engineering. However, no reports exist of PPC nanofibrous scaffolds for nerve tissue engineering. This study aimed to evaluate the potential role of aligned and random PPC nanofibrous scaffolds as substrates for peripheral nerve tissue and cells in nerve tissue engineering. Methods Aligned and random PPC nanofibrous scaffolds were fabricated by electrospinning and their chemical characterization were carried out using scanning electron microscopy (SEM). Dorsal root ganglia (DRG) from Sprague-Dawley rats were cultured on the nanofibrous substrates for 7 days. Neurite outgrowth and Schwann-cell migration from DRG were observed and quantified using immunocytochemistry and SEM. Schwann cells derived from rat sciatic nerves were cultured in electrospun PPC scaffold-extract fluid for 24, 48, 72 hours and 7 days. The viability of Schwann cells was evaluated by 3-[4,5-dimethyl(thiazol-2-yl)-2,5-diphenyl] tetrazolium bromide (MTT) assay. Results The diameter of aligned and random fibers ranged between 800 nm and 1200 nm, and the thickness of the films was approximately 10-20 μm. Quantification of aligned fiber films revealed approximately 90% alignment of all fibers along the longitudinal axis. However, with random fiber films, the alignment of fibers was random through all angle bins. Rat DRG explants were grown on PPC nanofiber films for up to 1 week. On the aligned fiber films, the majority of neurite outgrowth and Schwann cell migration from the DRG extended unidirectionally, parallel to the aligned fibers.However, on the random fiber films

  1. Bridging long gap peripheral nerve injury using skeletal muscle-derived multipotent stem cells

    Institute of Scientific and Technical Information of China (English)

    Tetsuro Tamaki

    2014-01-01

    Long gap peripheral nerve injuries usually reulting in life-changing problems for patients. Skeletal muscle derived-multipotent stem cells (Sk-MSCs) can differentiate into Schwann and perineurial/endoneurial cells, vascular relating pericytes, and endothelial and smooth muscle cells in the damaged peripheral nerve niche. Application of the Sk-MSCs in the bridging conduit for repairing long nerve gap injury resulted favorable axonal regeneration, which showing supe-rior effects than gold standard therapy--healthy nerve autograft. This means that it does not need to sacriifce of healthy nerves or loss of related functions for repairing peripheral nerve injury.

  2. Regeneration patterns influence hindlimb automutilation after sciatic nerve repair using stem cells in rats.

    Science.gov (United States)

    Haselbach, Daniel; Raffoul, Wassim; Larcher, Lorenz; Tremp, Mathias; Kalbermatten, Daniel F; di Summa, Pietro G

    2016-11-10

    Hindlimb autophagy is common after rat sciatic total axotomy and is considered as a sign of neuropathic pain. We applied adult stem cells in a fibrin conduit in a total sciatic axotomy model to improve nerve regeneration, investigating whether a correlation could be detected between stem cells effects on regeneration and limb autophagy. After sciatic nerve section, a 1-cm sciatic gap was crossed using fibrin conduits. Experimental groups included empty fibrin conduits, fibrin conduits seeded with primary Schwann cells, and fibrin conduits seeded with Schwann cell-like differentiated mesenchymal or adipose-derived stem cells (dMSCs and dASCs). Controls were represented by autografts and by sham rats (tot n=34). At 16 weeks post-implantation, regeneration pattern was analysed on histological sections and related to eventual autophagy. Hindlimbs were evaluated and scored according to autophagy Wall's scale and X-Rays radiological evaluation. All regenerative cell lines significantly improved myelination at the mid conduit level, compared to the empty tubes. However, dMSC could not significantly improve myelination at the distal stump, showing a more chaotic regeneration compared to both other cells groups and controls. Autophagy was correlated to this regeneration patterns, with higher autophagy scores in the empty and dMSC group. Hindlimb autophagy can be used as index of neuropathic pain due to nerve lesion or on-going immature regeneration. dMSC group was characterized by a less targeted regeneration comparing to dASC and primary Schwann cells, which confirmed their effectiveness in regeneration and potential in future clinical applications. Copyright © 2016. Published by Elsevier Ireland Ltd.

  3. Dynamics of degeneration and regeneration in developing zebrafish peripheral axons reveals a requirement for extrinsic cell types

    Directory of Open Access Journals (Sweden)

    Villegas Rosario

    2012-06-01

    Full Text Available Abstract Background Understanding the cellular mechanisms regulating axon degeneration and regeneration is crucial for developing treatments for nerve injury and neurodegenerative disease. In neurons, axon degeneration is distinct from cell body death and often precedes or is associated with the onset of disease symptoms. In the peripheral nervous system of both vertebrates and invertebrates, after degeneration of detached fragments, axons can often regenerate to restore function. Many studies of axonal degeneration and regeneration have used in vitro approaches, but the influence of extrinsic cell types on these processes can only be fully addressed in live animals. Because of its simplicity and superficial location, the larval zebrafish posterior lateral line (pLL nerve is an ideal model system for live studies of axon degeneration and regeneration. Results We used laser axotomy and time-lapse imaging of pLL axons to characterize the roles of leukocytes, Schwann cells and target sensory hair cells in axon degeneration and regeneration in vivo. Immune cells were essential for efficient removal of axonal debris after axotomy. Schwann cells were required for proper fasciculation and pathfinding of regenerating axons to their target cells. Intact target hair cells were not themselves required for regeneration, but chemical ablation of neuromasts caused axons to transiently deviate from their normal paths. Conclusions Macrophages, Schwann cells, and target sensory organs are required for distinct aspects of pLL axon degeneration or regeneration in the zebrafish larva. Our work introduces a powerful vertebrate model for analyzing axonal degeneration and regeneration in the living animal and elucidating the role of extrinsic cell types in these processes.

  4. Morphological, molecular and functional differences of adult bone marrow- and adipose-derived stem cells isolated from rats of different ages

    Energy Technology Data Exchange (ETDEWEB)

    Mantovani, Cristina [Blond McIndoe Laboratories, School of Biomedicine, The University of Manchester, Room 3,106 Stopford Building, Oxford Road, Manchester M13 9PT, Academic Health Science Centre, Faculty of Medicine and Human Sciences (United Kingdom); Department of Integrative Medical Biology and Surgical and Perioperative Science, Umea University, Umea (Sweden); Department of Surgical and Perioperative Science, Umea University, Umea (Sweden); Raimondo, Stefania [Dipartimento di Scienze Cliniche e Biologiche, University of Turin (Italy); Haneef, Maryam S. [Blond McIndoe Laboratories, School of Biomedicine, The University of Manchester, Room 3,106 Stopford Building, Oxford Road, Manchester M13 9PT, Academic Health Science Centre, Faculty of Medicine and Human Sciences (United Kingdom); Geuna, Stefano [Dipartimento di Scienze Cliniche e Biologiche, University of Turin (Italy); Terenghi, Giorgio [Blond McIndoe Laboratories, School of Biomedicine, The University of Manchester, Room 3,106 Stopford Building, Oxford Road, Manchester M13 9PT, Academic Health Science Centre, Faculty of Medicine and Human Sciences (United Kingdom); Shawcross, Susan G., E-mail: sue.shawcross@manchester.ac.uk [Blond McIndoe Laboratories, School of Biomedicine, The University of Manchester, Room 3,106 Stopford Building, Oxford Road, Manchester M13 9PT, Academic Health Science Centre, Faculty of Medicine and Human Sciences (United Kingdom); Wiberg, Mikael [Department of Integrative Medical Biology and Surgical and Perioperative Science, Umea University, Umea (Sweden); Department of Surgical and Perioperative Science, Umea University, Umea (Sweden)

    2012-10-01

    Adult mesenchymal stem cells have self-renewal and multiple differentiation potentials, and play important roles in regenerative medicine. However, their use may be limited by senescence or age of the donor, leading to changes in stem cell functionality. We investigated morphological, molecular and functional differences between bone marrow-derived (MSC) and adipose-derived (ASC) stem cells isolated from neonatal, young and old rats compared to Schwann cells from the same animals. Immunocytochemistry, RT-PCR, proliferation assays, western blotting and transmission electron microscopy were used to investigate expression of senescence markers. Undifferentiated and differentiated ASC and MSC from animals of different ages expressed Notch-2 at similar levels; protein-38 and protein-53 were present in all groups of cells with a trend towards increased levels in cells from older animals compared to those from neonatal and young rats. Following co-culture with adult neuronal cells, dMSC and dASC from animals of all ages elicited robust neurite outgrowth. Mitotracker{sup Registered-Sign} staining was consistent with ultrastructural changes seen in the mitochondria of cells from old rats, indicative of senescence. In conclusion, this study showed that although the cells from aged animals expressed markers of senescence, aged MSC and ASC differentiated into SC-like cells still retain potential to support axon regeneration. -- Highlights: Black-Right-Pointing-Pointer Aged MSC and ASC differentiated into Schwann-like cells support axon regeneration. Black-Right-Pointing-Pointer p53 expression does not appreciably influence the biology of Schwann or stem cells. Black-Right-Pointing-Pointer Notch 2 expression was similar in cells derived from animals of different ages. Black-Right-Pointing-Pointer Proliferation rates of dMSC varied little over time or with animal age.

  5. Tyrosine phosphatases epsilon and alpha perform specific and overlapping functions in regulation of voltage-gated potassium channels in Schwann cells

    DEFF Research Database (Denmark)

    Tiran, Zohar; Peretz, Asher; Sines, Tal

    2006-01-01

    Tyrosine phosphatases (PTPs) epsilon and alpha are closely related and share several molecular functions, such as regulation of Src family kinases and voltage-gated potassium (Kv) channels. Functional interrelationships between PTPepsilon and PTPalpha and the mechanisms by which they regulate K...... but are not fully redundant. We conclude that PTPepsilon and PTPalpha differ significantly in their regulation of Kv channels and Src in the system examined and that similarity between PTPs does not necessarily result in full functional redundancy in vivo....

  6. Ultrastructure of the neurohypophysis of the teleost Poecilia latipinna in relation to neural control of the adenohypophysial cells.

    Science.gov (United States)

    Batten, T F; Ball, J N

    1977-12-19

    The structure of the neurohypophysis of Poecilia latipinna (green molly, sailfin molly) was studied with the electron microscope. Profile diameters of neurosecretory granules in the non-myelinated neurohypophysial nerve fibres were measured and mathematically corrected for error due to section thickness. Six different types of nerve fibres could be distinguished by statistical classification of their granules and by other ultrastructural features. One fibre-type (type B) contained granules with a mean diameter of 85 nm, and the other five types (types Ala, Alb, A2, A3 and A4) all contained granules with mean diameters greater than 100 nm. Synaptic contacts were observed between type B fibres and all the adenohypophysial cell-types, although in the case of the ACTH cells the synapses were separated from the cell membrane by a continuous double basement membrane. Type A fibres were observed to contact the cells of the proximal pars distalis and pars intermedia, but did not form synapses. However, synapses occurred between type A fibres and pituicytes, and between type A fibres and the pericapillary basement membrane in the interior of the neurohypophysis. The possible roles of the different types of nerve fibres in controlling the adenohypophysial cells are discussed in the context of evidence from other teleosts.

  7. Dual mTORC1/2 inhibition induces anti-proliferative effect in NF1-associated plexiform neurofibroma and malignant peripheral nerve sheath tumor cells.

    Science.gov (United States)

    Varin, Jennifer; Poulain, Laury; Hivelin, Mikael; Nusbaum, Patrick; Hubas, Arnaud; Laurendeau, Ingrid; Lantieri, Laurent; Wolkenstein, Pierre; Vidaud, Michel; Pasmant, Eric; Chapuis, Nicolas; Parfait, Béatrice

    2016-06-14

    Approximately 30-50% of individuals with Neurofibromatosis type 1 develop benign peripheral nerve sheath tumors, called plexiform neurofibromas (PNFs). PNFs can undergo malignant transformation to highly metastatic malignant peripheral nerve sheath tumors (MPNSTs) in 5-10% of NF1 patients, with poor prognosis. No effective systemic therapy is currently available for unresectable tumors. In tumors, the NF1 gene deficiency leads to Ras hyperactivation causing the subsequent activation of the AKT/mTOR and Raf/MEK/ERK pathways and inducing multiple cellular responses including cell proliferation. In this study, three NF1-null MPNST-derived cell lines (90-8, 88-14 and 96-2), STS26T sporadic MPNST cell line and PNF-derived primary Schwann cells were used to test responses to AZD8055, an ATP-competitive "active-site" mTOR inhibitor. In contrast to rapamycin treatment which only partially affected mTORC1 signaling, AZD8055 induced a strong inhibition of mTORC1 and mTORC2 signaling in MPNST-derived cell lines and PNF-derived Schwann cells. AZD8055 induced full blockade of mTORC1 leading to an efficient decrease of global protein synthesis. A higher cytotoxic effect was observed with AZD8055 compared to rapamycin in the NF1-null MPNST-derived cell lines with IC50 ranging from 70 to 140 nM and antiproliferative effect was confirmed in PNF-derived Schwann cells. Cell migration was impaired by AZD8055 treatment and cell cycle analysis showed a G0/G1 arrest. Combined effects of AZD8055 and PD0325901 MEK inhibitor as well as BRD4 (BromoDomain-containing protein 4) inhibitors showed a synergistic antiproliferative effect. These data suggest that NF1-associated peripheral nerve sheath tumors are an ideal target for AZD8055 as a single molecule or in combined therapies.

  8. Dual mTORC1/2 inhibition induces anti-proliferative effect in NF1-associated plexiform neurofibroma and malignant peripheral nerve sheath tumor cells

    Science.gov (United States)

    Hivelin, Mikael; Nusbaum, Patrick; Hubas, Arnaud; Laurendeau, Ingrid; Lantieri, Laurent; Wolkenstein, Pierre; Vidaud, Michel; Pasmant, Eric; Chapuis, Nicolas; Parfait, Béatrice

    2016-01-01

    Approximately 30-50% of individuals with Neurofibromatosis type 1 develop benign peripheral nerve sheath tumors, called plexiform neurofibromas (PNFs). PNFs can undergo malignant transformation to highly metastatic malignant peripheral nerve sheath tumors (MPNSTs) in 5-10% of NF1 patients, with poor prognosis. No effective systemic therapy is currently available for unresectable tumors. In tumors, the NF1 gene deficiency leads to Ras hyperactivation causing the subsequent activation of the AKT/mTOR and Raf/MEK/ERK pathways and inducing multiple cellular responses including cell proliferation. In this study, three NF1-null MPNST-derived cell lines (90-8, 88-14 and 96-2), STS26T sporadic MPNST cell line and PNF-derived primary Schwann cells were used to test responses to AZD8055, an ATP-competitive “active-site” mTOR inhibitor. In contrast to rapamycin treatment which only partially affected mTORC1 signaling, AZD8055 induced a strong inhibition of mTORC1 and mTORC2 signaling in MPNST-derived cell lines and PNF-derived Schwann cells. AZD8055 induced full blockade of mTORC1 leading to an efficient decrease of global protein synthesis. A higher cytotoxic effect was observed with AZD8055 compared to rapamycin in the NF1-null MPNST-derived cell lines with IC50 ranging from 70 to 140 nM and antiproliferative effect was confirmed in PNF-derived Schwann cells. Cell migration was impaired by AZD8055 treatment and cell cycle analysis showed a G0/G1 arrest. Combined effects of AZD8055 and PD0325901 MEK inhibitor as well as BRD4 (BromoDomain-containing protein 4) inhibitors showed a synergistic antiproliferative effect. These data suggest that NF1-associated peripheral nerve sheath tumors are an ideal target for AZD8055 as a single molecule or in combined therapies. PMID:26840085

  9. Human umbilical cord mesenchymal stem cells promote peripheral nerve repairvia paracrine mechanisms

    Institute of Scientific and Technical Information of China (English)

    Zhi-yuan Guo; Xun Sun; Xiao-long Xu; Qing Zhao; Jiang Peng; Yu Wang

    2015-01-01

    Human umbilical cord-derived mesenchymal stem cells (hUCMSCs) represent a promising young-state stem cell source for cell-based therapy. hUCMSC transplantation into the transected sciatic nerve promotes axonal regeneration and functional recovery. To further clarify the para-crine effects of hUCMSCs on nerve regeneration, we performed human cytokine antibody array analysis, which revealed that hUCMSCs express 14 important neurotrophic factors. Enzyme-linked immunosorbent assay and immunohistochemistry showed that brain-derived neurotrophic factor, glial-derived neurotrophic factor, hepatocyte growth factor, neurotrophin-3, basic fibroblast growth factor, type I collagen, fibronectin and laminin were highly expressed. Treatment with hUCMSC-conditioned medium enhanced Schwann cell viability and proliferation, increased nerve growth factor and brain-derived neurotrophic factor expression in Schwann cells, and enhanced neurite growth from dorsal root ganglion explants. These ifndings suggest that paracrine action may be a key mechanism underlying the effects of hUCMSCs in peripheral nerve repair.

  10. Human umbilical cord mesenchymal stem cells promote peripheral nerve repair via paracrine mechanisms

    Directory of Open Access Journals (Sweden)

    Zhi-yuan Guo

    2015-01-01

    Full Text Available Human umbilical cord-derived mesenchymal stem cells (hUCMSCs represent a promising young-state stem cell source for cell-based therapy. hUCMSC transplantation into the transected sciatic nerve promotes axonal regeneration and functional recovery. To further clarify the paracrine effects of hUCMSCs on nerve regeneration, we performed human cytokine antibody array analysis, which revealed that hUCMSCs express 14 important neurotrophic factors. Enzyme-linked immunosorbent assay and immunohistochemistry showed that brain-derived neurotrophic factor, glial-derived neurotrophic factor, hepatocyte growth factor, neurotrophin-3, basic fibroblast growth factor, type I collagen, fibronectin and laminin were highly expressed. Treatment with hUCMSC-conditioned medium enhanced Schwann cell viability and proliferation, increased nerve growth factor and brain-derived neurotrophic factor expression in Schwann cells, and enhanced neurite growth from dorsal root ganglion explants. These findings suggest that paracrine action may be a key mechanism underlying the effects of hUCMSCs in peripheral nerve repair.

  11. Using Stem Cells to Grow Artificial Tissue for Peripheral Nerve Repair

    Directory of Open Access Journals (Sweden)

    Kulraj Singh Bhangra

    2016-01-01

    Full Text Available Peripheral nerve injury continues to pose a clinical hurdle despite its frequency and advances in treatment. Unlike the central nervous system, neurons of the peripheral nervous system have a greater ability to regenerate. However, due to a number of confounding factors, this is often both incomplete and inadequate. The lack of supportive Schwann cells or their inability to maintain a regenerative phenotype is a major factor. Advances in nervous system tissue engineering technology have led to efforts to build Schwann cell scaffolds to overcome this and enhance the regenerative capacity of neurons following injury. Stem cells that can differentiate along a neural lineage represent an essential resource and starting material for this process. In this review, we discuss the different stem cell types that are showing promise for nervous system tissue engineering in the context of peripheral nerve injury. We also discuss some of the biological, practical, ethical, and commercial considerations in using these different stem cells for future clinical application.

  12. Stereological quantification of immune-competent cells in baseline biopsy specimens from achilles tendons

    DEFF Research Database (Denmark)

    Kragsnaes, Maja Skov; Fredberg, Ulrich; Stribolt, Katrine

    2014-01-01

    immunohistochemically by quantifying the presence of macrophages (CD68-PGM1(+), CD68-KP1(+)), hemosiderophages (Perls blue), T lymphocytes (CD2(+), CD3(+), CD4(+), CD7(+), CD8(+)), B lymphocytes (CD20(+)), natural killer cells (CD56(+)), mast cells (NaSDCl(+)), Schwann cells (S100(+)), and endothelial cells (CD34......(+)) using a stereological technique. A follow-up examination was conducted more than 4 years (range, 4-9 years) after the biopsy procedure to evaluate the long-term presence of Achilles tendon symptoms. RESULTS: Macrophages, T lymphocytes, mast cells, and natural killer cells were observed in the majority......BACKGROUND: Limited data exist on the presence and function of immune-competent cells in chronic tendinopathic tendons and their potential role in inflammation and tissue healing as well as in predicting long-term outcome. PURPOSE: To quantify subtypes of immune-competent cells in biopsy specimens...

  13. Influence of Flow Behavior of Alginate-Cell Suspensions on Cell Viability and Proliferation.

    Science.gov (United States)

    Ning, Liqun; Guillemot, Arthur; Zhao, Jingxuan; Kipouros, Georges; Chen, Xiongbiao

    2016-07-01

    Tissue scaffolds with living cells fabricated by three-dimensional bioprinting/plotting techniques are becoming more prevalent in tissue repair and regeneration. In the bioprinting process, cells are subject to process-induced forces (such as shear force) that can result in cell damage and loss of cell function. The flow behavior of the biomaterial solutions that encapsulate living cells in this process plays an important role. This study used a rheometer to examine the flow behavior of alginate solution and alginate-Schwann cell (RSC96), alginate-fibroblast cell (NIH-3T3), and alginate-skeletal muscle cell (L8) suspensions during shearing with respect to effects on cell viability and proliferation. The flow behavior of all the alginate-cell suspensions varied with alginate concentration and cell density and had a significant influence on the viability and proliferation of the cells once sheared as well as on the recovery of the sheared cells. These findings provide a mean to preserve cell viability and/or retain cell proliferation function in the bioprinting process by regulating the flow behavior of cell-biomaterial suspensions and process parameters.

  14. HLA-DR-expressing cells and T-lymphocytes in sural nerve biopsies

    DEFF Research Database (Denmark)

    Schrøder, H D; Olsson, T; Solders, G;

    1988-01-01

    was confirmed. HLA-DR expression was found in all biopsies and thus was not restricted to any particular type of neuropathy. The HLA-DR expression appeared to correlate with severity and activity of the neuropathy. HLA-DR-expressing macrophages wrapping myelinated fibers were prominent in primary demyelinating......Thirty-five sural nerve biopsies were stained immunohistochemically for HLA-DR antigen. HLA-DR was expressed on nonmyelinating Schwann cells, macrophages, vascular endothelium, and perineurium. By means of double immunofluorescence staining the identity of the HLA-DR presenting structures...

  15. Mesenchymal Stem Cell-Like Cells Derived from Mouse Induced Pluripotent Stem Cells Ameliorate Diabetic Polyneuropathy in Mice

    Directory of Open Access Journals (Sweden)

    Tatsuhito Himeno

    2013-01-01

    Full Text Available Background. Although pathological involvements of diabetic polyneuropathy (DPN have been reported, no dependable treatment of DPN has been achieved. Recent studies have shown that mesenchymal stem cells (MSCs ameliorate DPN. Here we demonstrate a differentiation of induced pluripotent stem cells (iPSCs into MSC-like cells and investigate the therapeutic potential of the MSC-like cell transplantation on DPN. Research Design and Methods. For induction into MSC-like cells, GFP-expressing iPSCs were cultured with retinoic acid, followed by adherent culture for 4 months. The MSC-like cells, characterized with flow cytometry and RT-PCR analyses, were transplanted into muscles of streptozotocin-diabetic mice. Three weeks after the transplantation, neurophysiological functions were evaluated. Results. The MSC-like cells expressed MSC markers and angiogenic/neurotrophic factors. The transplanted cells resided in hindlimb muscles and peripheral nerves, and some transplanted cells expressed S100β in the nerves. Impairments of current perception thresholds, nerve conduction velocities, and plantar skin blood flow in the diabetic mice were ameliorated in limbs with the transplanted cells. The capillary number-to-muscle fiber ratios were increased in transplanted hindlimbs of diabetic mice. Conclusions. These results suggest that MSC-like cell transplantation might have therapeutic effects on DPN through secreting angiogenic/neurotrophic factors and differentiation to Schwann cell-like cells.

  16. [From the cell theory to the neuron theory].

    Science.gov (United States)

    Tixier-Vidal, Andrée

    2010-01-01

    The relationship between the cell theory formulated by Schwann (1839) and by Virchow (1855) on the one hand, and, on the other hand, the neuron theory, as formulated by Waldeyer (1891) and by Cajal (1906), are discussed from a historical point of view. Both of them are the result of technical and conceptuel progress. Both of them had to fight against the dominant dogma before being accepted. The cell theory opposed the school of Bichat, the vitalist philosophy and the positivist philosophy of Auguste Comte. The neuron theory, which is clearly based on the cell theory, was mostly concerned with the mode of interneuronal communication; it opposed the concept of contiguity to Golgi's concept of continuity. At present, the cell theory remains central in every field of Biology. By contrast, the neuron theory, which until the middle of the XXth century opened the study of the nervous system to a necessary reductionnist approach, is no longer central to recent developments of neurosciences.

  17. Cancer stem cell-like cells derived from malignant peripheral nerve sheath tumors.

    Directory of Open Access Journals (Sweden)

    Melanie Spyra

    Full Text Available This study aims to examine whether or not cancer stem cells exist in malignant peripheral nerve sheath tumors (MPNST. Cells of established lines, primary cultures and freshly dissected tumors were cultured in serum free conditions supplemented with epidermal and fibroblast growth factors. From one established human MPNST cell line, S462, cells meeting the criteria for cancer stem cells were isolated. Clonal spheres were obtained, which could be passaged multiple times. Enrichment of stem cell-like cells in these spheres was also supported by increased expression of stem cell markers such as CD133, Oct4, Nestin and NGFR, and decreased expression of mature cell markers such as CD90 and NCAM. Furthermore, cells of these clonal S462 spheres differentiated into Schwann cells, smooth muscle/fibroblast and neurons-like cells under specific differentiation-inducing cultural conditions. Finally, subcutaneous injection of the spheres into immunodeficient nude mice led to tumor formation at a higher rate compared to the parental adherent cells (66% versus 10% at 2.5 × 10(5. These results provide evidence for the existence of cancer stem cell-like cells in malignant peripheral nerve sheath tumors.

  18. Effects of sciatic-conditioned medium on neonatal rat retinal cells in vitro

    Directory of Open Access Journals (Sweden)

    Torres P.M.M.

    1998-01-01

    Full Text Available Schwann cells produce and release trophic factors that induce the regeneration and survival of neurons following lesions in the peripheral nerves. In the present study we examined the in vitro ability of developing rat retinal cells to respond to factors released from fragments of sciatic nerve. Treatment of neonatal rat retinal cells with sciatic-conditioned medium (SCM for 48 h induced an increase of 92.5 ± 8.8% (N = 7 for each group in the amount of total protein. SCM increased cell adhesion, neuronal survival and glial cell proliferation as evaluated by morphological criteria. This effect was completely blocked by 2.5 µM chelerythrine chloride, an inhibitor of protein kinase C (PKC. These data indicate that PKC activation is involved in the effect of SCM on retinal cells and demonstrate that fragments of sciatic nerve release trophic factors having a remarkable effect on neonatal rat retinal cells in culture.

  19. The potential for stem cells in cerebral palsy--piecing together the puzzle.

    Science.gov (United States)

    Faulkner, Stuart D; Ruff, Crystal A; Fehlings, Michael G

    2013-06-01

    The substantial socioeconomic burden of a diagnosis of cerebral palsy, coupled with a positive anecdotal and media spin on stem cell treatments, drives many affected families to seek information and treatment outside of the current clinical and scientific realm. Preclinical studies using several types of stem and adult cells--including mesenchymal stem cells, neural precursor cells, olfactory ensheathing glia and Schwann cells--have demonstrated some regenerative and functional efficacy in neurologic paradigms. This paper describes the most common cell types investigated for transplant in vivo and summarizes the current state of early-phase clinical trials. It investigates the most relevant and promising coadministered therapies, including rehabilitation, drug targeting, magnetic stimulation, and bioengineering approaches. We highlight the need for adjunctive combinatorial strategies to successfully transfer stem cell treatments from bench to bedside. Copyright © 2013 Elsevier Inc. All rights reserved.

  20. Cell Transplantation and Neuroengineering Approach for Spinal Cord Injury Treatment: A Summary of Current Laboratory Findings and Review of Literature.

    Science.gov (United States)

    Lin, Xin-Yi; Lai, Bi-Qin; Zeng, Xiang; Che, Ming-Tian; Ling, Eng-Ang; Wu, Wutian; Zeng, Yuan-Shan

    2016-01-01

    Spinal cord injury (SCI) can cause severe traumatic injury to the central nervous system (CNS). Current therapeutic effects achieved for SCI in clinical medicine show that there is still a long way to go to reach the desired goal of full or significant functional recovery. In basic medical research, however, cell transplantation, gene therapy, application of cytokines, and biomaterial scaffolds have been widely used and investigated as treatments for SCI. All of these strategies when used separately would help rebuild, to some extent, the neural circuits in the lesion area of the spinal cord. In light of this, it is generally accepted that a combined treatment may be a more effective strategy. This review focuses primarily on our recent series of work on transplantation of Schwann cells and adult stem cells, and transplantation of stem cell-derived neural network scaffolds with functional synapses. Arising from this, an artificial neural network (an exogenous neuronal relay) has been designed and fabricated by us-a biomaterial scaffold implanted with Schwann cells modified by the neurotrophin-3 (NT-3) gene and adult stem cells modified with the TrkC (receptor of NT-3) gene. More importantly, experimental evidence suggests that the novel artificial network can integrate with the host tissue and serve as an exogenous neuronal relay for signal transfer and functional improvement of SCI.

  1. Enhancing nerve regeneration in the peripheral nervous system using polymeric scaffolds, stem cell engineering and nanoparticle delivery system

    Science.gov (United States)

    Sharma, Anup Dutt

    Peripheral nerve regeneration is a complex biological process responsible for regrowth of neural tissue following a nerve injury. The main objective of this project was to enhance peripheral nerve regeneration using interdisciplinary approaches involving polymeric scaffolds, stem cell therapy, drug delivery and high content screening. Biocompatible and biodegradable polymeric materials such as poly (lactic acid) were used for engineering conduits with micropatterns capable of providing mechanical support and orientation to the regenerating axons and polyanhydrides for fabricating nano/microparticles for localized delivery of neurotrophic growth factors and cytokines at the site of injury. Transdifferentiated bone marrow stromal cells or mesenchymal stem cells (MSCs) were used as cellular replacements for lost native Schwann cells (SCs) at the injured nerve tissue. MSCs that have been transdifferentiated into an SC-like phenotype were tested as a substitute for the myelinating SCs. Also, genetically modified MSCs were engineered to hypersecrete brain- derived neurotrophic factor (BDNF) and glial cell line-derived neurotrophic factor (GDNF) to secrete therapeutic factors which Schwann cell secrete. To further enhance the regeneration, nerve growth factor (NGF) and interleukin-4 (IL4) releasing polyanhydrides nano/microparticles were fabricated and characterized in vitro for their efficacy. Synergistic use of these proposed techniques was used for fabricating a multifunctional nerve regeneration conduit which can be used as an efficient tool for enhancing peripheral nerve regeneration.

  2. The Urodele Limb Regeneration Blastema: The Cell Potential

    Directory of Open Access Journals (Sweden)

    Kenyon S. Tweedell

    2010-01-01

    Full Text Available The developmental potential of the limb regeneration blastema, a mass of mesenchymal cells of mixed origins, was once considered as being pluripotent, capable of forming all cell types. Now evidence asserts that the blastema is a heterogeneous mixture of progenitor cells derived from tissues of the amputation site, with limited developmental potential, plus various stem cells with multipotent abilities. Many specialized cells, bone, cartilage, muscle, and Schwann cells, at the injury site undergo dedifferentiation to a progenitor state and maintain their cell lineage as they redifferentiate in the regenerate. Muscle satellite reserve stem cells that are active in repair of injured muscle may also dedifferentiate and contribute new muscle cells to the limb blastema. Other cells from the dermis act as multipotent stem cells that replenish dermal fibroblasts and differentiate into cartilage. The blastema primordium is a self-organized, equipotential system, but at the cellular level can compensate for specific cell loss. It is able to induce dedifferentiation of introduced exogenous cells and such cells may be transformed into new cell types. Indigenous cells of the blastema associated with amputated tissues may also transform or possibly transdifferentiate into new cell types. The blastema is a microenvironment that enables dedifferentiation, redifferentiation, transdifferentiation, and stem cell activation, leading to progenitor cells of the limb regenerate.

  3. Comparison of cellular architecture, axonal growth, and blood vessel formation through cell-loaded polymer scaffolds in the transected rat spinal cord.

    Science.gov (United States)

    Madigan, Nicolas N; Chen, Bingkun K; Knight, Andrew M; Rooney, Gemma E; Sweeney, Eva; Kinnavane, Lisa; Yaszemski, Michael J; Dockery, Peter; O'Brien, Timothy; McMahon, Siobhan S; Windebank, Anthony J

    2014-11-01

    The use of multichannel polymer scaffolds in a complete spinal cord transection injury serves as a deconstructed model that allows for control of individual variables and direct observation of their effects on regeneration. In this study, scaffolds fabricated from positively charged oligo[poly(ethylene glycol)fumarate] (OPF(+)) hydrogel were implanted into rat spinal cords following T9 complete transection. OPF(+) scaffold channels were loaded with either syngeneic Schwann cells or mesenchymal stem cells derived from enhanced green fluorescent protein transgenic rats (eGFP-MSCs). Control scaffolds contained extracellular matrix only. The capacity of each scaffold type to influence the architecture of regenerated tissue after 4 weeks was examined by detailed immunohistochemistry and stereology. Astrocytosis was observed in a circumferential peripheral channel compartment. A structurally separate channel core contained scattered astrocytes, eGFP-MSCs, blood vessels, and regenerating axons. Cells double-staining with glial fibrillary acid protein (GFAP) and S-100 antibodies populated each scaffold type, demonstrating migration of an immature cell phenotype into the scaffold from the animal. eGFP-MSCs were distributed in close association with blood vessels. Axon regeneration was augmented by Schwann cell implantation, while eGFP-MSCs did not support axon growth. Methods of unbiased stereology provided physiologic estimates of blood vessel volume, length and surface area, mean vessel diameter, and cross-sectional area in each scaffold type. Schwann cell scaffolds had high numbers of small, densely packed vessels within the channels. eGFP-MSC scaffolds contained fewer, larger vessels. There was a positive linear correlation between axon counts and vessel length density, surface density, and volume fraction. Increased axon number also correlated with decreasing vessel diameter, implicating the importance of blood flow rate. Radial diffusion distances in vessels

  4. Malignant granular cell tumor of the abdominal wall mimicking desmoid tumor: A case report with CT imaging findings and literature review

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Je Hong; Ahn, Sung Eun; Lee, Dong Ho; Park, Seong Jin; Moon, Sung Kyoung; Lim, Joo Won [Dept. Radiology, Kyung Hee University Hospital, Kyung Hee University School of Medicine, Seoul (Korea, Republic of)

    2016-08-15

    Granular cell tumors (GCTs) are extremely rare mesenchymal neoplasms of Schwann cell origin. Malignant GCTs (MGCTs) comprise 0.5-2% of all GCTs. In the present report, we describe a case of a 66-year-old man with MGCT of the abdominal wall. The patient visited our hospital due to a recently growing palpable soft tissue mass in the abdominal wall. Computed tomography scan revealed a 4.3 × 4.1 × 2.9 cm sized mass arising from the left abdominal wall, which was contemplated as a desmoid tumor before surgical excision. Histopathological examination confirmed MGCT.

  5. Mechanotransduction in epidermal Merkel cells.

    Science.gov (United States)

    Nakatani, Masashi; Maksimovic, Srdjan; Baba, Yoshichika; Lumpkin, Ellen A

    2015-01-01

    The cellular and molecular basis of vertebrate touch reception remains least understood among the traditional five senses. Somatosensory afferents that innervate the skin encode distinct tactile qualities, such as flutter, slip, and pressure. Gentle touch is thought to be transduced by somatosensory afferents whose tactile end organs selectively filter mechanical stimuli. These tactile end organs comprise afferent terminals in association with non-neuronal cell types such as Merkel cells, keratinocytes, and Schwann cells. An open question is whether these non-neuronal cells serve primarily as passive mechanical filters or whether they actively participate in mechanosensory transduction. This question has been most extensively studied in Merkel cells, which are epidermal cells that complex with sensory afferents in regions of high tactile acuity such as fingertips, whisker follicles, and touch domes. Merkel cell-neurite complexes mediate slowly adapting type I (SAI) responses, which encode sustained pressure and represent object features with high fidelity. How Merkel cells contribute to unique SAI firing patterns has been debated for decades; however, three recent studies in rodent models provide some direct answers. First, whole-cell recordings demonstrate that Merkel cells are touch-sensitive cells with fast, mechanically activated currents that require Piezo2. Second, optogenetics and intact recordings show that Merkel cells mediate sustained SAI firing. Finally, loss-of-function studies in transgenic mouse models reveal that SAI afferents are also touch sensitive. Together, these studies identify molecular mechanisms of mechanotransduction in Merkel cells, reveal unexpected functions for these cells in touch, and support a revised, two-receptor site model of mechanosensory transduction.

  6. Nerve root degeneration and regeneration by intrathecal phenol in rats: a morphologic approach.

    Science.gov (United States)

    Romero-Figueroa, Socorro; Aldrete, J Antonio; Martínez-Cruz, Angelina; Orozco, Sandra; Castillo, Sebastian; Castillo-Henkel, Carlos; Guízar-Sahagún, Gabriel

    2006-12-01

    Intrathecal injection of phenol (ITP) has been used to control intractable pain and spasticity. Direct caustic nerve damage has been postulated as the mechanism of analgesia. Sensation is commonly recovered, suggesting that a spontaneous regeneration process takes place. There is, however, a lack of mechanistic information on ITP therapy. To define morphologically the neurolysis and regeneration phenomena produced by ITP, anesthetized rats were subjected to laminectomy at L5; 5 microl of 22% phenol in saline solution or vehicle (control) was injected. Light and electron microscopy studies of nerve roots were performed at 2, 14, and 60 days after injection. Rats given ITP showed at the early stage a variable amount of roots with signs of infarction characterized by loss of axon-myelin units and thrombosis of intra-root vessels. At 14 days, abundance of macrophages removing debris, open vessels, and nerve sprouts was identified in damaged roots. At this time, non-myelinating glial fibrillary acidic protein-positive Schwann cells were observed in both damaged and apparently undamaged roots. At 60 days, abundance of 2',3'-cyclic nucleotide 3'-phosphodiesterase-positive Schwann cells myelinating newly formed axons was observed in damaged roots. Control rats did not show signs of neural or vascular pathology. Attempting to prevent thrombosis, another group of rats received heparin before ITP; these anti-coagulated rats developed radicular thrombosis, neurolysis, and hemorrhage. In conclusion, neurolysis produced by ITP is associated with acute ischemia (not prevented by heparin) and is followed by vascular, nerve, and myelin regeneration. Our results help understand the lack of efficacy of and some complications by ITP clinical therapy.

  7. Large enhancement in neurite outgrowth on a cell membrane-mimicking conducting polymer

    Science.gov (United States)

    Zhu, Bo; Luo, Shyh-Chyang; Zhao, Haichao; Lin, Hsing-An; Sekine, Jun; Nakao, Aiko; Chen, Chi; Yamashita, Yoshiro; Yu, Hsiao-Hua

    2014-07-01

    Although electrically stimulated neurite outgrowth on bioelectronic devices is a promising means of nerve regeneration, immunogenic scar formation can insulate electrodes from targeted cells and tissues, thereby reducing the lifetime of the device. Ideally, an electrode material capable of electrically interfacing with neurons selectively and efficiently would be integrated without being recognized by the immune system and minimize its response. Here we develop a cell membrane-mimicking conducting polymer possessing several attractive features. This polymer displays high resistance towards nonspecific enzyme/cell binding and recognizes targeted cells specifically to allow intimate electrical communication over long periods of time. Its low electrical impedance relays electrical signals efficiently. This material is capable to integrate biochemical and electrical stimulation to promote neural cellular behaviour. Neurite outgrowth is enhanced greatly on this new conducting polymer; in addition, electrically stimulated secretion of proteins from primary Schwann cells can also occur on it.

  8. A Novel Model for Acute Peripheral Nerve Injury in the Horse and Evaluation of the Effect of Mesenchymal Stromal Cells Applied In Situ on Nerve Regeneration: A Preliminary Study

    Science.gov (United States)

    Cruz Villagrán, Claudia; Schumacher, Jim; Donnell, Robert; Dhar, Madhu S.

    2016-01-01

    Transplantation of mesenchymal stromal cells (MSCs) to sites of experimentally created nerve injury in laboratory animals has shown promising results in restoring nerve function. This approach for nerve regeneration has not been reported in horses. In this study, we first evaluated the in vitro ability of equine bone marrow-derived MSCs (EBM-MSCs) to trans-differentiate into Schwann-like cells and subsequently tested the MSCs in vivo for their potential to regenerate a transected nerve after implantation. The EBM-MSCs from three equine donors were differentiated into SCLs for 7 days, in vitro, in the presence of specialized differentiation medium and evaluated for morphological characteristics, by using confocal microscopy, and for protein characteristics, by using selected Schwann cell markers (GFAP and S100b). The EBM-MSCs were then implanted into the fascia surrounding the ramus communicans of one fore limb of three healthy horses after a portion of this nerve was excised. The excised portion of the nerve was examined histologically at the time of transection, and stumps of the nerve were examined histologically at day 45 after transplantation. The EBM-MSCs from all donors demonstrated morphological and protein characteristics of those of Schwann cells 7 days after differentiation. Nerves implanted with EBM-MSCs after nerve transection did not show evidence of nerve regeneration at day 45. Examination of peripheral nerves collected 45 days after injury and stem cell treatment revealed no histological differences between nerves treated with MSCs and those treated with isotonic saline solution (controls). The optimal delivery of MSCs and the model suitable to study the efficacy of MSCs in nerve regeneration should be investigated. PMID:27695697

  9. Combination of fibrin-agarose hydrogels and adipose-derived mesenchymal stem cells for peripheral nerve regeneration

    Science.gov (United States)

    Carriel, Víctor; Garrido-Gómez, Juan; Hernández-Cortés, Pedro; Garzón, Ingrid; García-García, Salomé; Sáez-Moreno, José Antonio; Sánchez-Quevedo, María del Carmen; Campos, Antonio; Alaminos, Miguel

    2013-04-01

    Objective. The objective was to study the effectiveness of a commercially available collagen conduit filled with fibrin-agarose hydrogels alone or with fibrin-agarose hydrogels containing autologous adipose-derived mesenchymal stem cells (ADMSCs) in a rat sciatic nerve injury model. Approach. A 10 mm gap was created in the sciatic nerve of 48 rats and repaired using saline-filled collagen conduits or collagen conduits filled with fibrin-agarose hydrogels alone (acellular conduits) or with hydrogels containing ADMSCs (ADMSC conduits). Nerve regeneration was assessed in clinical, electrophysiological and histological studies. Main results. Clinical and electrophysiological outcomes were more favorable with ADMSC conduits than with the acellular or saline conduits, evidencing a significant recovery of sensory and motor functions. Histological analysis showed that ADMSC conduits produce more effective nerve regeneration by Schwann cells, with higher remyelination and properly oriented axonal growth that reached the distal areas of the grafted conduits, and with intensely positive expressions of S100, neurofilament and laminin. Extracellular matrix was also more abundant and better organized around regenerated nerve tissues with ADMSC conduits than those with acellular or saline conduits. Significance. Clinical, electrophysiological and histological improvements obtained with tissue-engineered ADMSC conduits may contribute to enhancing axonal regeneration by Schwann cells.

  10. Breast schwannoma in a patient with diffuse large B-cell lymphoma: a case report

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    Salihoglu Ayse

    2012-12-01

    Full Text Available Abstract Introduction Schwannomas are mostly benign tumors arising from Schwann cells of the nerve sheaths. Breast schwannomas are very rare and account for only 2.6% of cases. As far as we know this is the first reported case of breast schwannoma discovered in a patient with diffuse large B-cell lymphoma. The breast schwannoma was evaluated with positron emission tomography and it exhibited moderate 18F-fluorodeoxyglucose uptake. Case presentation We present the case of a breast schwannoma in a 63-year-old Caucasian woman who was diagnosed with diffuse large B-cell lymphoma. Conclusion Imaging modalities including positron emission tomography-computed tomography failed to distinguish breast schwannoma from diffuse large B-cell lymphoma involvement of the breast.

  11. BNIP3 regulates AT101 [(--gossypol] induced death in malignant peripheral nerve sheath tumor cells.

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    Niroop Kaza

    Full Text Available Malignant peripheral nerve sheath tumors (MPNSTs are aggressive Schwann cell-derived sarcomas and are the leading cause of mortality in patients with neurofibromatosis type 1 (NF1. Current treatment modalities have been largely ineffective, resulting in a high rate of MPNST recurrence and poor five-year patient survival. This necessitates the exploration of alternative chemotherapeutic options for MPNST patients. This study sought to assess the cytotoxic effect of the BH3-mimetic AT101 [(--gossypol] on MPNST cells in vitro and to identify key regulators of AT101-induced MPNST cell death. We found that AT101 caused caspase-independent, non-apoptotic MPNST cell death, which was accompanied by autophagy and was mediated through HIF-1α induced expression of the atypical BH3-only protein BNIP3. These effects were mediated by intracellular iron chelation, a previously unreported mechanism of AT101 cytotoxicity.

  12. BNIP3 regulates AT101 [(-)-gossypol] induced death in malignant peripheral nerve sheath tumor cells.

    Science.gov (United States)

    Kaza, Niroop; Kohli, Latika; Graham, Christopher D; Klocke, Barbara J; Carroll, Steven L; Roth, Kevin A

    2014-01-01

    Malignant peripheral nerve sheath tumors (MPNSTs) are aggressive Schwann cell-derived sarcomas and are the leading cause of mortality in patients with neurofibromatosis type 1 (NF1). Current treatment modalities have been largely ineffective, resulting in a high rate of MPNST recurrence and poor five-year patient survival. This necessitates the exploration of alternative chemotherapeutic options for MPNST patients. This study sought to assess the cytotoxic effect of the BH3-mimetic AT101 [(-)-gossypol] on MPNST cells in vitro and to identify key regulators of AT101-induced MPNST cell death. We found that AT101 caused caspase-independent, non-apoptotic MPNST cell death, which was accompanied by autophagy and was mediated through HIF-1α induced expression of the atypical BH3-only protein BNIP3. These effects were mediated by intracellular iron chelation, a previously unreported mechanism of AT101 cytotoxicity.

  13. Biodegradable chitin conduit tubulation combined with bone marrow mesenchymal stem cell transplantation for treatment of spinal cord injury by reducing glial scar and cavity formation

    Institute of Scientific and Technical Information of China (English)

    Feng Xue; Er-jun Wu; Pei-xun Zhang; Li-ya A; Yu-hui Kou; Xiao-feng Yin; Na Han

    2015-01-01

    We examined the restorative effect of modiifed biodegradable chitin conduits in combination with bone marrow mesenchymal stem cell transplantation after right spinal cord hemisection injury. Immunohistochemical staining revealed that biological conduit sleeve bridging reduced glial scar formation and spinal muscular atrophy after spinal cord hemisection. Bone marrow mesenchymal stem cells survived and proliferated after transplantationin vivo, and differentiated into cells double-positive for S100 (Schwann cell marker) and glial ifbrillary acidic protein (glial cell marker) at 8 weeks. Retrograde tracing showed that more nerve ifbers had grown through the injured spinal cord at 14 weeks after combination therapy than either treatment alone. Our ifndings indicate that a biological conduit combined with bone marrow mesenchymal stem cell transplantation effectively prevented scar formation and provided a favorable local microenvi-ronment for the proliferation, migration and differentiation of bone marrow mesenchymal stem cells in the spinal cord, thus promoting restoration following spinal cord hemisection injury.

  14. Transplantation of neural progenitor cells differentiated from adipose tissue-derived stem cells for treatment of sciatic nerve injury

    Institute of Scientific and Technical Information of China (English)

    Shasha Dong§; Na Liu§; Yang Hu ; Ping Zhang; Chao Pan; Youping Zhang; Yingxin Tang; Zhouping Tang 

    2016-01-01

    Objectives: Currently, the clinical repair of sciatic nerve injury remains difficult. Previous studies have confirmed that transplantation of adipose tissue-derived stem cells promotes nerve regeneration and restoration at peripheral nerve injury sites. Methods:In this study, adipose tissue-derived stem cells were induced to differentiate into neural progenitor cells, transfected with a green fluorescent protein-containing lentivirus, and then transplanted into the lesions of rats with sciatic nerve compression injury. Results: Fluorescence microscopy revealed that the transplanted cells survived, migrated, and differentiated in rats. At two weeks post-operation, a large number of transplanted cells had migrated to the injured lesions; at six weeks post-operation, transplanted cells were visible around the injured nerve and several cells were observed to express a Schwann cell marker. Sciatic function index and electrophysiological outcomes of the transplantation group were better than those of the control group. Cell transplantation promoted the recovery of motor nerve conduction velocity and com-pound muscle action potential amplitude, and reduced gastrocnemius muscle atrophy. Conclusions: Our experimental findings indicate that neural progenitor cells, differentiated from adipose tissue-derived stem cells, are potential seed stem cells that can be transplanted into lesions to treat sciatic nerve injury. This provides a theoretical basis for their use in clinical applications.

  15. Differentiation of Equine Mesenchymal Stromal Cells into Cells of Neural Lineage: Potential for Clinical Applications

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    Claudia Cruz Villagrán

    2014-01-01

    Full Text Available Mesenchymal stromal cells (MSCs are able to differentiate into extramesodermal lineages, including neurons. Positive outcomes were obtained after transplantation of neurally induced MSCs in laboratory animals after nerve injury, but this is unknown in horses. Our objectives were to test the ability of equine MSCs to differentiate into cells of neural lineage in vitro, to assess differences in morphology and lineage-specific protein expression, and to investigate if horse age and cell passage number affected the ability to achieve differentiation. Bone marrow-derived MSCs were obtained from young and adult horses. Following demonstration of stemness, MSCs were neurally induced and microscopically assessed at different time points. Results showed that commercially available nitrogen-coated tissue culture plates supported proliferation and differentiation. Morphological changes were immediate and all the cells displayed a neural crest-like cell phenotype. Expression of neural progenitor proteins, was assessed via western blot or immunofluorescence. In our study, MSCs generated from young and middle-aged horses did not show differences in their ability to undergo differentiation. The effect of cell passage number, however, is inconsistent and further experiments are needed. Ongoing work is aimed at transdifferentiating these cells into Schwann cells for transplantation into a peripheral nerve injury model in horses.

  16. Vestibular Schwannoma (Acoustic Neuroma) and Neurofibromatosis

    Science.gov (United States)

    ... the inner ear. The tumor comes from an overproduction of Schwann cells—the cells that normally wrap ... begin to develop new therapies to control the overproduction of Schwann cells in individuals with vestibular schwannoma. ...

  17. Germline Transgenic Methods for Tracking Cells and Testing Gene Function during Regeneration in the Axolotl

    Science.gov (United States)

    Khattak, Shahryar; Schuez, Maritta; Richter, Tobias; Knapp, Dunja; Haigo, Saori L.; Sandoval-Guzmán, Tatiana; Hradlikova, Kristyna; Duemmler, Annett; Kerney, Ryan; Tanaka, Elly M.

    2013-01-01

    The salamander is the only tetrapod that regenerates complex body structures throughout life. Deciphering the underlying molecular processes of regeneration is fundamental for regenerative medicine and developmental biology, but the model organism had limited tools for molecular analysis. We describe a comprehensive set of germline transgenic strains in the laboratory-bred salamander Ambystoma mexicanum (axolotl) that open up the cellular and molecular genetic dissection of regeneration. We demonstrate tissue-dependent control of gene expression in nerve, Schwann cells, oligodendrocytes, muscle, epidermis, and cartilage. Furthermore, we demonstrate the use of tamoxifen-induced Cre/loxP-mediated recombination to indelibly mark different cell types. Finally, we inducibly overexpress the cell-cycle inhibitor p16INK4a, which negatively regulates spinal cord regeneration. These tissue-specific germline axolotl lines and tightly inducible Cre drivers and LoxP reporter lines render this classical regeneration model molecularly accessible. PMID:24052945

  18. A Case of Granular Cell Tumor of the Clitoris in a Postmenopausal Woman.

    Science.gov (United States)

    Min, Ji-Won; Kim, Yun-Sook

    2017-08-01

    Granular cell tumor (GCT) is a rare soft tissue tumor that derived from Schwann cells. Most are benign, less than 2% are malignant and, in the malignant cases, the prognosis of survival is poor. Most of these tumors are less than 3 cm in size, and they are more common in black women. The disease usually occurs in the 40s to the 60s and occurs after menopause, but there are few cases reported in adolescence. A 45-year-old woman visited the outpatient clinic with a solid mass that developed 2 years ago and present to date on the left side of the clitoris. After complete resection, pathologic examination proved to be a granular cell. The patient has been living without recurrence for one year. We report the first case of the GCT of the clitoris in postmenopausal woman in Korea with a brief review of the literature.

  19. An animal model of peripheral nerve regeneration after the application of a collagen-polyvinyl alcohol scaffold and mesenchymal stem cells.

    Science.gov (United States)

    Marinescu, Silviu Adrian; Zărnescu, Otilia; Mihai, Ioana Ruxandra; Giuglea, Carmen; Sinescu, Ruxandra Diana

    2014-01-01

    Extensive nerve injuries often leading to nerve gaps can benefit, besides the gold standard represented by autologous nerve grafts, by the inciting field of tissue engineering. To enhance the role of biomaterials in nerve regeneration, the nerve conduits are associated with Schwann or Schwann-like cells. In this study, we evaluated rat sciatic nerve regeneration, by using a biodegradable nerve guide composed of Collagen (COL) and Polyvinyl Alcohol (PVA), associated with mesenchymal stem cells (MSC). After the exposure of the rat sciatic nerve, a nerve gap was created by excising 1 cm of the nerve. Three experimental groups were used for nerve gap bridging: autografts, nerve conduits filled with medium culture and nerve conduits filled with MSC. The methods of sensory and motor assessment consisted of the functional evaluation of sciatic nerve recovery - toe-spread, pinprick tests and gastrocnemius muscle index (GMI). The histological and immunocytochemical analysis of the probes that were harvested from the repair site was performed at 12 weeks. Successful nerve regeneration was noted in all three groups at the end of the 12th week. The functional and immunocytochemical results suggested that COL-PVA tubes supported with mesenchymal stem cells could be considered similar to autologous nerve grafts in peripheral nerve regeneration, without the drawbacks of the last ones. The functional results were better for the autografts and the ultrastructural data were better for the nerve conduits, but there were not noticed any statistical differences.

  20. Preferential and comprehensive reconstitution of severely damaged sciatic nerve using murine skeletal muscle-derived multipotent stem cells.

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    Tetsuro Tamaki

    Full Text Available Loss of vital functions in the somatic motor and sensory nervous systems can be induced by severe peripheral nerve transection with a long gap following trauma. In such cases, autologous nerve grafts have been used as the gold standard, with the expectation of activation and proliferation of graft-concomitant Schwann cells associated with their paracrine effects. However, there are a limited number of suitable sites available for harvesting of nerve autografts due to the unavoidable sacrifice of other healthy functions. To overcome this problem, the potential of skeletal muscle-derived multipotent stem cells (Sk-MSCs was examined as a novel alternative cell source for peripheral nerve regeneration. Cultured/expanded Sk-MSCs were injected into severely crushed sciatic nerve corresponding to serious neurotmesis. After 4 weeks, engrafted Sk-MSCs preferentially differentiated into not only Schwann cells, but also perineurial/endoneurial cells, and formed myelin sheath and perineurium/endoneurium, encircling the regenerated axons. Increased vascular formation was also observed, leading to a favorable blood supply and waste product excretion. In addition, engrafted cells expressed key neurotrophic and nerve/vascular growth factor mRNAs; thus, endocrine/paracrine effects for the donor/recipient cells were also expected. Interestingly, skeletal myogenic capacity of expanded Sk-MSCs was clearly diminished in peripheral nerve niche. The same differentiation and tissue reconstitution capacity of Sk-MSCs was sufficiently exerted in the long nerve gap bridging the acellular conduit, which facilitated nerve regeneration/reconnection. These effects represent favorable functional recovery in Sk-MSC-treated mice, as demonstrated by good corduroy walking. We also demonstrated that these differentiation characteristics of the Sk-MSCs were comparable to native peripheral nerve-derived cells, whereas the therapeutic capacities were largely superior in Sk

  1. Cells

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    Zhao-Hui Jin

    2012-11-01

    Full Text Available As cancer stem cells (CSCs are postulated to play critical roles in cancer development, including metastasis and recurrence, CSC imaging would provide valuable information for cancer treatment and lead to CSC-targeted therapy. To assess the possibility of in vivo CSC targeting, we conducted basic studies on radioimmunotargeting of cancer cells positive for CD133, a CSC marker recognized in various cancers. Antibodies against CD133 were labeled with 125I, and their in vitro cell binding properties were tested. Using the same isotype IgG as a control, in vivo biodistribution of the labeled antibody retaining immunoreactivity was examined in mice bearing an HCT116 xenograft in which a population of the cancer cells expressed CD133. Intratumoral distribution of the labeled antibody was examined and compared to the CD133 expression pattern. The 125I-labeled anti-CD133 antibody showed a modest but significantly higher accumulation in the HCT116 xenograft compared to the control IgG. The intratumoral distribution of the labeled antibody mostly overlapped with the CD133 expression, whereas the control IgG was found in the area close to the necrotic tumor center. Our results indicate that noninvasive in vivo targeting of CSCs could be possible with radiolabeled antibodies against cell membrane markers.

  2. Enzymatic quantification of sphingosine in the picomole range in cultured cells

    Energy Technology Data Exchange (ETDEWEB)

    Van Veldhoven, P.P.; Bishop, W.R.; Bell, R.M. (Duke Univ. Medical Center, Durham, NC (USA))

    1989-11-15

    An enzymatic method to quantify the mass levels of free sphingosine in cellular lipid extracts was developed. The assay is based upon the observation that ceramide is phosphorylated by Escherichia coli diacylglycerol kinase. Although sphingosine is not recognized by the enzyme, it can be converted to a substrate by acylation with hexanoic anhydride. Using a mixed micellar assay, previously reported for the mass quantification of diacylglycerol, the short-chain ceramide (N-C6-sphingosine), generated by acylation, is quantitatively phosphorylated to N-C6-(32P)sphingosine phosphate. This assay allows quantification of sphingosine over a broad range from 25 to 5000 pmol. When this assay was applied to standard compounds, reverse-phase thin-layer chromatography of the reaction products was adequate to separate the phosphorylated derivatives of long-chain ceramide and N-C6-sphingosine. However, the presence of other lipids in extracts from biological samples (mainly monoalkylglycerols which are also a substrate for the diacylglycerol kinase) interfered and necessitated an additional purification step. The most efficient purification step devised was a combination of anion- and cation-exchange chromatography. The mass levels of free sphingoid bases in different cultured cells were quantified using this assay. Levels varied between 8 to 20 pmol/10(6) cells. When normalized to phospholipids, sphingosine levels varied between 0.01 and 0.04 mol%. The lowest levels were found in L929 cells, while Schwann cells derived from Twitcher mice contained the highest levels. These levels were significantly higher than those of Schwann cells derived from normal mice.

  3. Cell transplantation for the treatment of spinal cord injury- bone marrow stromal cells and choroid plexus epithelial cells

    Institute of Scientific and Technical Information of China (English)

    Chizuka Ide; Norihiko Nakano; Kenji Kanekiyo

    2016-01-01

    Transplantation of bone marrow stromal cells (BMSCs) enhanced the outgrowth of regenerating axons and promoted locomotor improvements of rats with spinal cord injury (SCI). BMSCs did not survive long-term, disappearing from the spinal cord within 2–3 weeks after transplantation. Astrocyte-devoid areas, in which no astrocytes or oligodendrocytes were found, formed at the epicenter of the lesion. It was remarkable that numerous regenerating axons extended through such astrocyte-devoid areas. Regenerating axons were associated with Schwann cells embedded in extracellular matrices. Transplantation of choroid plexus epithelial cells (CPECs) also enhanced axonal regeneration and locomotor improvements in rats with SCI. Although CPECs disappeared from the spinal cord shortly after transplantation, an extensive outgrowth of regenerating axons occurred through astrocyte-devoid areas, as in the case of BMSC transplantation. These ifndings suggest that BMSCs and CPECs secret neurotrophic factors that promote tissue repair of the spinal cord, including axonal regeneration and reduced cavity formation. This means that transplantation of BMSCs and CPECs promotes “intrinsic” ability of the spinal cord to regenerate. The treatment to stimu-late the intrinsic regeneration ability of the spinal cord is the safest method of clinical application for SCI. It should be emphasized that the generally anticipated long-term survival, proliferation and differentiation of transplanted cells are not necessarily desirable from the clinical point of view of safety.

  4. Cell transplantation for the treatment of spinal cord injury - bone marrow stromal cells and choroid plexus epithelial cells.

    Science.gov (United States)

    Ide, Chizuka; Nakano, Norihiko; Kanekiyo, Kenji

    2016-09-01

    Transplantation of bone marrow stromal cells (BMSCs) enhanced the outgrowth of regenerating axons and promoted locomotor improvements of rats with spinal cord injury (SCI). BMSCs did not survive long-term, disappearing from the spinal cord within 2-3 weeks after transplantation. Astrocyte-devoid areas, in which no astrocytes or oligodendrocytes were found, formed at the epicenter of the lesion. It was remarkable that numerous regenerating axons extended through such astrocyte-devoid areas. Regenerating axons were associated with Schwann cells embedded in extracellular matrices. Transplantation of choroid plexus epithelial cells (CPECs) also enhanced axonal regeneration and locomotor improvements in rats with SCI. Although CPECs disappeared from the spinal cord shortly after transplantation, an extensive outgrowth of regenerating axons occurred through astrocyte-devoid areas, as in the case of BMSC transplantation. These findings suggest that BMSCs and CPECs secret neurotrophic factors that promote tissue repair of the spinal cord, including axonal regeneration and reduced cavity formation. This means that transplantation of BMSCs and CPECs promotes "intrinsic" ability of the spinal cord to regenerate. The treatment to stimulate the intrinsic regeneration ability of the spinal cord is the safest method of clinical application for SCI. It should be emphasized that the generally anticipated long-term survival, proliferation and differentiation of transplanted cells are not necessarily desirable from the clinical point of view of safety.

  5. Antigens expressed by myelinating glia cells induce peripheral cross-tolerance of endogenous CD8+ T cells.

    Science.gov (United States)

    Schildknecht, Anita; Probst, Hans Christian; McCoy, Kathy D; Miescher, Iris; Brenner, Corinne; Leone, Dino P; Suter, Ueli; Ohashi, Pamela S; van den Broek, Maries

    2009-06-01

    Auto-reactivity of T cells is largely prevented by central and peripheral tolerance. Nevertheless, immunization with certain self-antigens emulsified in CFA induces autoimmunity in rodents, suggesting that tolerance to some self-antigens is not robust. To investigate the fate of nervous system-specific CD8(+) T cells, which only recently came up as being important contributors for MS pathogenesis, we developed a mouse model that allows inducible expression of lymphocytic choriomeningitis virus-derived CD8(+) T-cell epitopes specifically in oligodendrocytes and Schwann cells, the myelinating glia of the nervous system. These transgenic CD8(+) T-cell epitopes induced robust tolerance of endogenous auto-reactive T cells, which proved thymus-independent and was mediated by cross-presenting bone-marrow-derived cells. Immunohistological staining of secondary lymphoid organs demonstrated the presence of glia-derived antigens in DC, suggesting that peripheral tolerance of CD8(+) T cells results from uptake and presentation by steady state DC.

  6. Magnetic nanoparticles in primary neural cell cultures are mainly taken up by microglia

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    Pinkernelle Josephine

    2012-03-01

    Full Text Available Abstract Background Magnetic nanoparticles (MNPs offer a large range of applications in life sciences. Applications in neurosciences are one focus of interest. Unfortunately, not all groups have access to nanoparticles or the possibility to develop and produce them for their applications. Hence, they have to focus on commercially available particles. Little is known about the uptake of nanoparticles in primary cells. Previously studies mostly reported cellular uptake in cell lines. Here we present a systematic study on the uptake of magnetic nanoparticles (MNPs by primary cells of the nervous system. Results We assessed the internalization in different cell types with confocal and electron microscopy. The analysis confirmed the uptake of MNPs in the cells, probably with endocytotic mechanisms. Furthermore, we compared the uptake in PC12 cells, a rat pheochromocytoma cell line, which is often used as a neuronal cell model, with primary neuronal cells. It was found that the percentage of PC12 cells loaded with MNPs was significantly higher than for neurons. Uptake studies in primary mixed neuronal/glial cultures revealed predominant uptake of MNPs by microglia and an increase in their number. The number of astroglia and oligodendroglia which incorporated MNPs was lower and stable. Primary mixed Schwann cell/fibroblast cultures showed similar MNP uptake of both cell types, but the Schwann cell number decreased after MNP incubation. Organotypic co-cultures of spinal cord slices and peripheral nerve grafts resembled the results of the dispersed primary cell cultures. Conclusions The commercial MNPs used activated microglial phagocytosis in both disperse and organotypic culture systems. It can be assumed that in vivo application would induce immune system reactivity, too. Because of this, their usefulness for in vivo neuroscientific implementations can be questioned. Future studies will need to overcome this issue with the use of cell

  7. Spiral Ganglion Cells and Macrophages Initiate Neuro-inflammation and Scarring Following Cochlear Implantation

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    Esperanza eBas

    2015-08-01

    Full Text Available Conservation of a patient’s residual hearing and prevention of fibrous tissue/new bone formation around an electrode array are some of the major challenges in cochlear implant (CI surgery. Although it is well known that fibrotic tissue formation around the electrode array can interfere with hearing performance in implanted patients, and that associated intracochlear inflammation can initiate loss of residual hearing, little is known about the molecular and cellular mechanisms that promote this response in the cochlea. In vitro studies in neonatal rats and in vivo studies in adult mice were performed to gain insight into the pro-inflammatory, proliferative, and remodeling phases of pathological wound healing that occur in the cochlea following an electrode analogue insertion. Resident Schwann cells, macrophages/microglia, and fibroblasts had a prominent role in the inflammatory process in the cochlea. Leukocytes were recruited to the cochlea following insertion of a nylon filament in adult mice, where contributed to the inflammatory response. The reparative stages in wound healing are characterized by persistent neuro-inflammation of spiral ganglion neurons and expression of regenerative macrophages in the cochlea. Accordingly, genes involved in extracellular matrix deposition and remodeling were up-regulated in implanted cochleae.Maturation of scar tissue occurs in the remodeling phase of wound healing in the cochlea. Similar to other damaged peripheral nerves, M2 macrophages and de-differentiated Schwann cells were observed in damaged cochleae and may play a role in cell survival and axonal regeneration. In conclusion, the insertion of an electrode analogue into the cochlea is associated with robust early and chronic inflammatory responses characterized by recruitment of leukocytes and expression of pro-inflammatory cytokines that promote intracochlear fibrosis and loss of auditory hair cells and spiral ganglion neurons important for hearing

  8. Are neural crest stem cells the missing link between hematopoietic and neurogenic niches?

    Science.gov (United States)

    Coste, Cécile; Neirinckx, Virginie; Gothot, André; Wislet, Sabine; Rogister, Bernard

    2015-01-01

    Hematopoietic niches are defined as cellular and molecular microenvironments that regulate hematopoietic stem cell (HSC) function together with stem cell autonomous mechanisms. Many different cell types have been characterized as contributors to the formation of HSC niches, such as osteoblasts, endothelial cells, Schwann cells, and mesenchymal progenitors. These mesenchymal progenitors have themselves been classified as CXC chemokine ligand (CXCL) 12-abundant reticular (CAR) cells, stem cell factor expressing cells, or nestin-positive mesenchymal stem cells (MSCs), which have been recently identified as neural crest-derived cells (NCSCs). Together, these cells are spatially associated with HSCs and believed to provide appropriate microenvironments for HSC self-renewal, differentiation, mobilization and hibernation both by cell-cell contact and soluble factors. Interestingly, it appears that regulatory pathways governing the hematopoietic niche homeostasis are operating in the neurogenic niche as well. Therefore, this review paper aims to compare both the regulation of hematopoietic and neurogenic niches, in order to highlight the role of NCSCs and nervous system components in the development and the regulation of the hematopoietic system.

  9. Are neural crest stem cells the missing link between hematopoietic and neurogenic niches?

    Directory of Open Access Journals (Sweden)

    Cécile eCoste

    2015-06-01

    Full Text Available Hematopoietic niches are defined as cellular and molecular microenvironments that regulate hematopoietic stem cell (HSC function together with stem cell autonomous mechanisms. Many different cell types have been characterized as contributors to the formation of HSC niches, such as osteoblasts, endothelial cells, Schwann cells, and mesenchymal progenitors. These mesenchymal progenitors have themselves been classified as CXC chemokine ligand (CXCL12-abundant reticular (CAR cells, stem cell factor expressing cells, or nestin-positive mesenchymal stem cells (MSCs, which have been recently identified as neural crest-derived cells (NCSCs. Together, these cells are spatially associated with HSCs and believed to provide appropriate microenvironments for HSC self-renewal, differentiation, mobilization and hibernation both by cell-to-cell contact and soluble factors. Interestingly, it appears that regulatory pathways governing the hematopoietic niche homeostasis are operating in the neurogenic niche as well. Therefore, this review paper aims to compare both the regulation of hematopoietic and neurogenic niches, in order to highlight the role of NCSCs and nervous system components in the development and the regulation of the hematopoietic system.

  10. Induction of Skin-Derived Precursor Cells from Human Induced Pluripotent Stem Cells

    Science.gov (United States)

    Sugiyama-Nakagiri, Yoriko; Fujimura, Tsutomu; Moriwaki, Shigeru

    2016-01-01

    The generation of full thickness human skin from dissociated cells is an attractive approach not only for treating skin diseases, but also for treating many systemic disorders. However, it is currently not possible to obtain an unlimited number of skin dermal cells. The goal of this study was to develop a procedure to produce skin dermal stem cells from induced pluripotent stem cells (iPSCs). Skin-derived precursor cells (SKPs) were isolated as adult dermal precursors that could differentiate into both neural and mesodermal progenies and could reconstitute the dermis. Thus, we attempted to generate SKPs from iPSCs that could reconstitute the skin dermis. Human iPSCs were initially cultured with recombinant noggin and SB431542, an inhibitor of activin/nodal and TGFβ signaling, to induce neural crest progenitor cells. Those cells were then treated with SKP medium that included CHIR99021, a WNT signal activator. The induction efficacy from neural crest progenitor cells to SKPs was more than 97%. No other modifiers tested were able to induce those cells. Those human iPSC-derived SKPs (hiPSC-SKPs) showed a similar gene expression signature to SKPs isolated from human skin dermis. Human iPSC-SKPs differentiated into neural and mesodermal progenies, including adipocytes, skeletogenic cell types and Schwann cells. Moreover, they could be induced to follicular type keratinization when co-cultured with human epidermal keratinocytes. We here provide a new efficient protocol to create human skin dermal stem cells from hiPSCs that could contribute to the treatment of various skin disorders. PMID:27992514

  11. CNPase Expression in Olfactory Ensheathing Cells

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    Christine Radtke

    2011-01-01

    Full Text Available A large body of work supports the proposal that transplantation of olfactory ensheathing cells (OECs into nerve or spinal cord injuries can promote axonal regeneration and remyelination. Yet, some investigators have questioned whether the transplanted OECs associate with axons and form peripheral myelin, or if they recruit endogenous Schwann cells that form myelin. Olfactory bulbs from transgenic mice expressing the enhanced green fluorescent protein (eGFP under the control of the 2-3-cyclic nucleotide 3-phosphodiesterase (CNPase promoter were studied. CNPase is expressed in myelin-forming cells throughout their lineage. We examined CNPase expression in both in situ in the olfactory bulb and in vitro to determine if OECs express CNPase commensurate with their myelination potential. eGFP was observed in the outer nerve layer of the olfactory bulb. Dissociated OECs maintained in culture had both intense eGFP expression and CNPase immunostaining. Transplantation of OECs into transected peripheral nerve longitudinally associated with the regenerated axons. These data indicate that OECs in the outer nerve layer of the olfactory bulb of CNPase transgenic mice express CNPase. Thus, while OECs do not normally form myelin on olfactory nerve axons, their expression of CNPase is commensurate with their potential to form myelin when transplanted into injured peripheral nerve.

  12. Transplantation of Nogo-66 receptor gene-silenced cells in a poly(D,L-lactic-co-glycolic acid) scaffold for the treatment of spinal cord injury★

    Science.gov (United States)

    Wang, Dong; Fan, Yuhong; Zhang, Jianjun

    2013-01-01

    Inhibition of neurite growth, which is in large part mediated by the Nogo-66 receptor, affects neural regeneration following bone marrow mesenchymal stem cell transplantation. The tissue engineering scaffold poly(D,L-lactide-co-glycolic acid) has good histocompatibility and can promote the growth of regenerating nerve fibers. The present study used small interfering RNA to silence Nogo-66 receptor gene expression in bone marrow mesenchymal stem cells and Schwann cells, which were subsequently transplanted with poly(D,L-lactide-co-glycolic acid) into the spinal cord lesion regions in rats. Simultaneously, rats treated with scaffold only were taken as the control group. Hematoxylin-eosin staining and immunohistochemistry revealed that at 4 weeks after transplantation, rats had good motor function of the hind limb after treatment with Nogo-66 receptor gene-silenced cells plus the poly(D,L-lactide-co-glycolic acid) scaffold compared with rats treated with scaffold only, and the number of bone marrow mesenchymal stem cells and neuron-like cells was also increased. At 8 weeks after transplantation, horseradish peroxidase tracing and transmission electron microscopy showed a large number of unmyelinated and myelinated nerve fibers, as well as intact regenerating axonal myelin sheath following spinal cord hemisection injury. These experimental findings indicate that transplantation of Nogo-66 receptor gene-silenced bone marrow mesenchymal stem cells and Schwann cells plus a poly(D,L-lactide-co-glycolic acid) scaffold can significantly enhance axonal regeneration of spinal cord neurons and improve motor function of the extremities in rats following spinal cord injury. PMID:25206713

  13. Transplantation of Nogo-66 receptor gene-silenced cells in a poly(D,L-lactic-co-glycolic acid) scaffold for the treatment of spinal cord injury.

    Science.gov (United States)

    Wang, Dong; Fan, Yuhong; Zhang, Jianjun

    2013-03-15

    Inhibition of neurite growth, which is in large part mediated by the Nogo-66 receptor, affects neural regeneration following bone marrow mesenchymal stem cell transplantation. The tissue engineering scaffold poly(D,L-lactide-co-glycolic acid) has good histocompatibility and can promote the growth of regenerating nerve fibers. The present study used small interfering RNA to silence Nogo-66 receptor gene expression in bone marrow mesenchymal stem cells and Schwann cells, which were subsequently transplanted with poly(D,L-lactide-co-glycolic acid) into the spinal cord lesion regions in rats. Simultaneously, rats treated with scaffold only were taken as the control group. Hematoxylin-eosin staining and immunohistochemistry revealed that at 4 weeks after transplantation, rats had good motor function of the hind limb after treatment with Nogo-66 receptor gene-silenced cells plus the poly(D,L-lactide-co-glycolic acid) scaffold compared with rats treated with scaffold only, and the number of bone marrow mesenchymal stem cells and neuron-like cells was also increased. At 8 weeks after transplantation, horseradish peroxidase tracing and transmission electron microscopy showed a large number of unmyelinated and myelinated nerve fibers, as well as intact regenerating axonal myelin sheath following spinal cord hemisection injury. These experimental findings indicate that transplantation of Nogo-66 receptor gene-silenced bone marrow mesenchymal stem cells and Schwann cells plus a poly(D,L-lactide-co-glycolic acid) scaffold can significantly enhance axonal regeneration of spinal cord neurons and improve motor function of the extremities in rats following spinal cord injury.

  14. Transplantation of Nogo-66 receptor gene-silenced cells in a poly(D,L-lactic-co-glycolic acid) scaffold for the treatment of spinal cord injury

    Institute of Scientific and Technical Information of China (English)

    Dong Wang; Yuhong Fan; Jianjun Zhang

    2013-01-01

    Inhibition of neurite growth, which is in large part mediated by the Nogo-66 receptor, affects neural regeneration following bone marrow mesenchymal stem cell transplantation. The tissue engineering scaffold poly(D,L-lactide-co-glycolic acid) has good histocompatibility and can promote the growth of regenerating nerve fibers. The present study used small interfering RNA to silence Nogo-66 receptor gene expression in bone marrow mesenchymal stem cells and Schwann cells, which were subsequently transplanted with poly(D,L-lactide-co-glycolic acid) into the spinal cord lesion regions in rats. Simultaneously, rats treated with scaffold only were taken as the control group. Hematoxylin-eosin staining and immunohistochemistry revealed that at 4 weeks after transplantation, rats had good motor function of the hind limb after treatment with Nogo-66 receptor gene-silenced cells plus the poly(D,L-lactide-co-glycolic acid) scaffold compared with rats treated with scaffold only, and the number of bone marrow mesenchymal stem cells and neuron-like cells was also increased. At 8 weeks after transplantation, horseradish peroxidase tracing and transmission electron microscopy showed a large number of unmyelinated and myelinated nerve fibers, as well as intact regenerating axonal myelin sheath following spinal cord hemisection injury. These experimental findings indicate that transplantation of Nogo-66 receptor gene-silenced bone marrow mesenchymal stem cells and Schwann cells plus a poly(D,L-lactide-co-glycolic acid) scaffold can significantly enhance axonal regeneration of spinal cord neurons and improve motor function of the extremities in rats following spinal cord injury.

  15. Cell theory, specificity, and reproduction, 1837-1870.

    Science.gov (United States)

    Müller-Wille, Staffan

    2010-09-01

    The cell is not only the structural, physiological, and developmental unit of life, but also the reproductive one. So far, however, this aspect of the cell has received little attention from historians and philosophers of biology. I will argue that cell theory had far-reaching consequences for how biologists conceptualized the reproductive relationships between germs and adult organisms. Cell theory, as formulated by Theodor Schwann in 1839, implied that this relationship was a specific and lawful one, that is, that germs of a certain kind, all else being equal, would produce adult organisms of the same kind, and vice versa. Questions of preformation and epigenesis took on a new meaning under this presupposition. The question then became one of whether cells could be considered as autonomous agents producing adult organisms of a given species, or whether they were the product of external, organizing forces and thus only a stage in the development of the whole organism. This question became an important issue for nineteenth-century biology. As I will demonstrate, it was the view of cells as autonomous agents which helped both Charles Darwin and Gregor Mendel to think of inheritance as a lawful process.

  16. Sciatic nerve repair with tissue engineered nerve: Olfactory ensheathing cells seeded poly(lactic-co-glygolic acid conduit in an animal model

    Directory of Open Access Journals (Sweden)

    C W Tan

    2013-01-01

    Full Text Available Background and Aim: Synthetic nerve conduits have been sought for repair of nerve defects as the autologous nerve grafts causes donor site morbidity and possess other drawbacks. Many strategies have been investigated to improve nerve regeneration through synthetic nerve guided conduits. Olfactory ensheathing cells (OECs that share both Schwann cell and astrocytic characteristics have been shown to promote axonal regeneration after transplantation. The present study was driven by the hypothesis that tissue-engineered poly(lactic-co-glycolic acid (PLGA seeded with OECs would improve peripheral nerve regeneration in a long sciatic nerve defect. Materials and Methods: Sciatic nerve gap of 15 mm was created in six adult female Sprague-Dawley rats and implanted with PLGA seeded with OECs. The nerve regeneration was assessed electrophysiologically at 2, 4 and 6 weeks following implantation. Histopathological examination, scanning electron microscopic (SEM examination and immunohistochemical analysis were performed at the end of the study. Results: Nerve conduction studies revealed a significant improvement of nerve conduction velocities whereby the mean nerve conduction velocity increases from 4.2 ΁ 0.4 m/s at week 2 to 27.3 ΁ 5.7 m/s at week 6 post-implantation ( P < 0.0001. Histological analysis revealed presence of spindle-shaped cells. Immunohistochemical analysis further demonstrated the expression of S100 protein in both cell nucleus and the cytoplasm in these cells, hence confirming their Schwann-cell-like property. Under SEM, these cells were found to be actively secreting extracellular matrix. Conclusion: Tissue-engineered PLGA conduit seeded with OECs provided a permissive environment to facilitate nerve regeneration in a small animal model.

  17. Platelet-rich plasma-induced bone marrow mesenchymal stem cells versus autologous nerve grafting for sciatic nerve repair

    Institute of Scientific and Technical Information of China (English)

    Changsuo Xia; Yajuan Li; Wen Cao; Zhaohua Yu

    2010-01-01

    Autologous nerve grafting is the gold standard of peripheral nerve repair.We previously showed that autologous platelet-rich plasma(PRP)contains high concentrations of growth factors and can induce in vitro cultured bone marrow mesenchymal stem cells(BMSCs)to differentiate into Schwann cells.Here we used PRP-induced BMSCs combined with chemically extracted acellular nerves to repair sciatic nerve defects and compared the effect with autologous nerve grafting.The BMSCs and chemically extracted acellular nerve promoted target muscle wet weight restoration,motor nerve conduction velocity,and axonal and myelin sheath regeneration,with similar effectiveness to autologous nerve grafting.This finding suggests that PRP induced BMSCs can be used to repair peripheral nerve defects.

  18. 体外培养过程中许旺细胞S100表达规律研究%Research of S100 Expression Regularity of Cultured Schwann Cells In Vitro

    Institute of Scientific and Technical Information of China (English)

    刘璋寅; 沈尊理; 金羽青; 程佳; 陈露露; 沈华

    2013-01-01

    目的:目前研究发现,周围神经中许旺细胞的标志物有很多,S100是其中之一.S100在体内表达的变化规律已有比较深入的研究,但是其在体外培养的许旺细胞的表达规律尚不清楚.因此,本课题研究小鼠许旺细胞在体外培养过程中S100蛋白的表达变化规律.方法:取新生(出生5-7 d)C57BL/6小鼠的坐骨神经,酶消化分离获取细胞后,培养纯化扩增3次.用S100免疫荧光法及RT-PCR技术研究许旺细胞在体外培养过程中S100的表达规律.结果:从坐骨神经消化所得到的许旺细胞,早期并不都表达S100,阳性率约为43.48%,随着培养时间延长(培养8天),所有许旺细胞均表达S100,能够达到阳性率95.66%.结论:体外培养的许旺细胞,其标志物S100阳性率表达随培养时间延长而增加.并且我们发现,S100并不能作为一个可靠的标志物来单独应用鉴定体外培养早期的许旺细胞.

  19. Immortalized human dorsal root ganglion cells differentiate into neurons with nociceptive properties.

    Science.gov (United States)

    Raymon, H K; Thode, S; Zhou, J; Friedman, G C; Pardinas, J R; Barrere, C; Johnson, R M; Sah, D W

    1999-07-01

    A renewable source of human sensory neurons would greatly facilitate basic research and drug development. We had established previously conditionally immortalized human CNS cell lines that can differentiate into functional neurons (). We report here the development of an immortalized human dorsal root ganglion (DRG) clonal cell line, HD10.6, with a tetracycline-regulatable v-myc oncogene. In the proliferative condition, HD10.6 cells have a doubling time of 1.2 d and exhibit a neuronal precursor morphology. After differentiation of clone HD10.6 for 7 d in the presence of tetracycline, v-myc expression was suppressed, and >50% of the cells exhibited typical neuronal morphology, stained positively for neuronal cytoskeletal markers, and fired action potentials in response to current injection. Furthermore, this cell line was fate-restricted to a neuronal phenotype; even in culture conditions that promote Schwann cell or smooth muscle differentiation of neural crest stem cells, HD10.6 differentiated exclusively into neurons. Moreover, differentiated HD10.6 cells expressed sensory neuron-associated transcription factors and exhibited capsaicin sensitivity. Taken together, these data indicate that we have established an immortalized human DRG cell line that can differentiate into sensory neurons with nociceptive properties. The cell line HD10.6 represents the first example of a human sensory neuronal line and will be valuable for basic research, as well as for the discovery of novel drug targets and clinical candidates.

  20. 髓鞘结构在听神经瘤组织中的检测%Detect myelin structure in acoustic tumor

    Institute of Scientific and Technical Information of China (English)

    王琰; 姜海洋; 于何; 关超; 姜学钧

    2011-01-01

    目的:探讨来源于施万细胞的人类听神经细胞瘤组织中是否存在髓鞘结构及其细胞学特点.方法:应用免疫荧光标记、Western blotting及电镜等方法检测听神经瘤组织中的髓鞘结构及重要髓鞘蛋白.结果:电镜结果发现:听神经瘤组织中虽然缺失成熟的轴索结构但可以检测到早期的髓鞘样结构.免疫荧光研究和Western blotting研究结果显示:听神经瘤组织中检测不到轴索的标志性抗体--神经丝200的表达.并且启动髓鞘化的前哨信号及髓鞘致密化的重要组成蛋白--髓鞘碱性蛋白在听神经瘤组织中也无法检测到.而一种非成熟施万细胞的标志抗体--神经生长因子受体p75,在听神经瘤组织中可以检测到其表达.结论:在听神经瘤组织中的施万细胞失去了完成髓鞘化进程和重新形成致密的髓鞘并包绕轴索的能力,处于前髓鞘化施万细胞阶段.%Objective:By detecting the myelin structure in acoustic tumor tissues, the cell origin and state of acoustic tumor tissues were investigated. Method: Immunofluorescence labeling, immunoblot analysis and electron microscopic study were performed to identify myelin structure and myelin protein in acoustic tumor tissues. Result:In this work, we found some early stage of myelin forming in acoustic tumor tissues, but there were no axon nor compact myelin formed and the myelin basic protein whose expression indicates the beginning of myelination was negative detected. We also found that the cell of acoustic tumor express p75,a marker for immature Schwann cells and mature non-myelin-forming Schwann cells. Conclusion:The date shown in this experiment indicates that the cell of acoustic tumor is in a premyelinating state.

  1. Oncogene Mutation Survey in MPNST Cell Lines Enhances the Dominant Role of Hyperactive Ras in NF1 Associated Pro-Survival and Malignancy.

    Science.gov (United States)

    Sun, Daochun; Tainsky, Michael A; Haddad, Ramsi

    2012-01-01

    Malignant peripheral nerve sheath tumors (MPNST) are a type of soft tissue sarcoma that can be associated with germline mutations in Neurofibromatosis type 1 (NF1) or may occur sporadically. Although the etiology of MPNST is poorly understood, it is clear that a loss of function of the NF1 gene, encoding a Ras-GAP, is an important factor in the tumorigenesis of the inherited form of MPNST. Tumor latency in NF1 patients suggests that additional mutational events are probably required for malignancy. In order to define oncogene mutations associated with 5 MPNST cell lines, we assayed the 238 most frequent mutations in 19 commonly activated oncogenes using mass spectroscopy-based analysis. All 238 mutation sites in the assayed oncogenes were determined to harbor only wild-type sequences. These data suggest that hyperactive Ras resulting from the loss function of neurofibromin may be sufficient to set up the direction of malignant transformation of Schwann cells to MPNST.

  2. Gap junction disorders of myelinating cells.

    Science.gov (United States)

    Kleopa, Kleopas A; Orthmann-Murphy, Jennifer; Sargiannidou, Irene

    2010-01-01

    Gap junctions (GJs) are channels that allow the diffusion of ions and small molecules across apposed cell membranes. In peripheral nerves, Schwann cells express the GJ proteins connexin32 (Cx32) and Cx29, which have distinct localizations. Cx32 forms GJs through non-compact myelin areas, whereas Cx29 forms hemichannels in the innermost layers of myelin apposing axonal Shaker-type K+ channels. In the CNS, rodent oligodendrocytes express Cx47, Cx32 and Cx29. Cx47 is expressed by all types of oligodendrocytes both in the white and grey matter and forms GJs on cell bodies and proximal processes, as well as most of the intercellular channels with astrocytes. Cx32 is expressed mostly by white matter oligodendrocytes and is localized in the myelin sheath of large diameter fibers. Cx29, and its human ortholog Cx31.3, appear to be restricted to oligodendrocytes that myelinate small caliber fibers, likely forming hemichannels. The importance of intercellular and intracellular GJs in myelinating cells are demonstrated by human disorders resulting from mutations affecting GJ proteins. The X-linked Charcot Marie Tooth disease (CMT1X) is caused by hundreds of mutations affecting Cx32. Patients with CMT1X present mainly with a progressive peripheral neuropathy, which may be accompanied by CNS myelin dysfunction. Mutations in Cx47 may cause a devastating leukodystrophy called Pelizaeus-Merzbacher-like disease or a milder spastic paraplegia. In addition, CNS demyelination may be caused by defects in genes expressing astrocytic GJ proteins, which are essential for oligodendrocytes. Findings from in vitro and in vivo models of these disorders developed over the last decade indicate that most mutations cause loss of function and an inability of the mutant connexins to form functional GJs. Here we review the clinical, genetic, and neurobiological aspects of GJ disorders affecting the PNS and CNS myelinating cells.

  3. Use of FK506 and bone marrow mesenchymal stem cells for rat hind limb allografts

    Institute of Scientific and Technical Information of China (English)

    Youxin Song; Zhujun Wang; Zhixue Wang; Hong Zhang; Xiaohui Li; Bin Chen

    2012-01-01

    Dark Agouti rat donor hind limbs were orthotopically transplanted into Lewis rat recipients to verify the effects of bone marrow mesenchymal stem cells on neural regeneration and functional recovery of allotransplanted limbs in the microenvironment of immunotolerance. bone marrow mesenchymal stem cells were intramuscularly (gluteus maximus) injected with FK506 (tacrolimus) daily, and were transplanted to the injured nerves. Results indicated that the allograft group not receiving therapy showed severe rejection, with transplanted limbs detaching at 10 days after transplantation with complete necrosis. The number of myelinated axons and Schwann cells in the FK506 and FK506 + bone marrow mesenchymal stem cells groups were significantly increased. We observed a lesser degree of gastrocnemius muscle degeneration, and increased polymorphic fibers along with other pathological changes in the FK506 + bone marrow mesenchymal stem cells group. The FK506 + bone marrow mesenchymal stem cells group showed significantly better recovery than the autograft and FK506 groups. The results demonstrated that FK506 improved the immune microenvironment. FK506 combined with bone marrow mesenchymal stem cells significantly promoted sciatic nerve regeneration, and improved sensory recovery and motor function in hind limb allotransplant.

  4. Molecular mechanisms of gap junction mutations in myelinating cells.

    Science.gov (United States)

    Sargiannidou, Irene; Markoullis, Kyriaki; Kleopa, Kleopas A

    2010-09-01

    There is an emerging group of neurological disorders that result from genetic mutations affecting gap junction proteins in myelinating cells. The X-linked form of Charcot Marie Tooth disease (CMT1X) is caused by numerous mutations in the GJB1 gene encoding the gap junction protein connexin32 (Cx32), which is expressed in both Schwann cells in the PNS and oligodendrocytes in the CNS. Patients with CMT1X present mainly with a progressive peripheral neuropathy, showing mixed axonal and demyelinating features. In many cases there is also clinical or subclinical involvement of the CNS with acute or chronic phenotypes of encephalopathy. Furthermore, mutations in the GJA12/GJC2 gene encoding the gap junction protein Cx47, which is expressed in oligodendrocytes, have been identified in families with progressive leukodystrophy, known as Pelizaeus-Merzbacher-like disease, as well as in patients with hereditary spastic paraplegia. Recent studies have provided insights into the pattern of gap junction protein expression and function in CNS and PNS myelinating cells. Furthermore, in vitro and in vivo disease models have clarified some of the molecular and cellular mechanisms underlying these disorders. Here we provide an overview of the clinical, genetic, and neurobiological aspects of gap junction disorders affecting the nervous system.

  5. An orthotopic xenograft model of intraneural NF1 MPNST suggests a potential association between steroid hormones and tumor cell proliferation.

    Science.gov (United States)

    Perrin, George Q; Li, Hua; Fishbein, Lauren; Thomson, Susanne A; Hwang, Min S; Scarborough, Mark T; Yachnis, Anthony T; Wallace, Margaret R; Mareci, Thomas H; Muir, David

    2007-11-01

    Malignant peripheral nerve sheath tumors (MPNST) are the most aggressive cancers associated with neurofibromatosis type 1 (NF1). Here we report a practical and reproducible model of intraneural NF1 MPNST, by orthotopic xenograft of an immortal human NF1 tumor-derived Schwann cell line into the sciatic nerves of female scid mice. Intraneural injection of the cell line sNF96.2 consistently produced MPNST-like tumors that were highly cellular and showed extensive intraneural growth. These xenografts had a high proliferative index, were angiogenic, had significant mast cell infiltration and rapidly dominated the host nerve. The histopathology of engrafted intraneural tumors was consistent with that of human NF1 MPNST. Xenograft tumors were readily examined by magnetic resonance imaging, which also was used to assess tumor vascularity. In addition, the intraneural proliferation of sNF96.2 cell tumors was decreased in ovariectomized mice, while replacement of estrogen or progesterone restored tumor cell proliferation. This suggests a potential role for steroid hormones in supporting tumor cell growth of this MPNST cell line in vivo. The controlled orthotopic implantation of sNF96.2 cells provides for the precise initiation of intraneural MPNST-like tumors in a model system suitable for therapeutic interventions, including inhibitors of angiogenesis and further study of steroid hormone effects on tumor cell growth.

  6. Characterizing Mystery Cell Lines: Student-driven Research Projects in an Undergraduate Neuroscience Laboratory Course

    Science.gov (United States)

    Lemons, Michele L.

    2012-01-01

    Inquiry-based projects promote discovery and retention of key concepts, increase student engagement, and stimulate interest in research. Described here are a series of lab exercises within an undergraduate upper level neuroscience course that train students to design, execute and analyze their own hypothesis-driven research project. Prior to developing their own projects, students learn several research techniques including aseptic cell culture, cell line maintenance, immunocytochemistry and fluorescent microscopy. Working in groups, students choose how to use these techniques to characterize and identify a “mystery” cell line. Each lab group is given a unique cell line with either a neural, astrocyte, or Schwann cell origin. Working together, students plan and execute experiments to determine the cellular origin and other unique characteristics of their mystery cell line. Students generate testable hypotheses, design interpretable experiments, generate and analyze data, and report their findings in both oral and written formats. Students receive instructor and peer feedback throughout the entire project. In summary, these labs train students the process of scientific research. This series of lab exercises received very strong positive feedback from the students. Reflections on student feedback and plans for future improvements are discussed. PMID:23504583

  7. Characterizing Mystery Cell Lines: Student-driven Research Projects in an Undergraduate Neuroscience Laboratory Course.

    Science.gov (United States)

    Lemons, Michele L

    2012-01-01

    Inquiry-based projects promote discovery and retention of key concepts, increase student engagement, and stimulate interest in research. Described here are a series of lab exercises within an undergraduate upper level neuroscience course that train students to design, execute and analyze their own hypothesis-driven research project. Prior to developing their own projects, students learn several research techniques including aseptic cell culture, cell line maintenance, immunocytochemistry and fluorescent microscopy. Working in groups, students choose how to use these techniques to characterize and identify a "mystery" cell line. Each lab group is given a unique cell line with either a neural, astrocyte, or Schwann cell origin. Working together, students plan and execute experiments to determine the cellular origin and other unique characteristics of their mystery cell line. Students generate testable hypotheses, design interpretable experiments, generate and analyze data, and report their findings in both oral and written formats. Students receive instructor and peer feedback throughout the entire project. In summary, these labs train students the process of scientific research. This series of lab exercises received very strong positive feedback from the students. Reflections on student feedback and plans for future improvements are discussed.

  8. The potential for stem cell therapies to have an impact on cerebral palsy: opportunities and limitations.

    Science.gov (United States)

    Ruff, Crystal A; Faulkner, Stuart D; Fehlings, Michael G

    2013-08-01

    Cerebral palsy (CP) is a chronic childhood disorder described by a group of motor and cognitive impairments and results in a substantial socio-economic burden to the individual, family, and healthcare system. With no effective biological interventions, therapies for CP are currently restricted to supportive and management strategies. Cellular transplantation has been suggested as a putative intervention for neural pathology, as mesenchymal and neural stem cells, as well as olfactory ensheathing glia and Schwann cells, have shown some regenerative and functional efficacy in experimental central nervous system disorders. This review describes the most common cell types investigated and delineates their purported mechanisms in vivo. Furthermore, it provides a cogent summary of both current early-phase clinical trials using neural precursor cells (NPCs) and the state of stem cell therapies for neurodegenerative conditions. Although NPCs are perhaps the most promising candidates for cell replacement therapy in the context of CP, much still remains to be understood regarding safety, efficacy, timing, dose, and route of transplantation, as well as the capacity for combinatorial strategies. © 2013 Mac Keith Press.