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Multifunctional, multichannel bridges that deliver neurotrophin encoding lentivirus for regeneration following spinal cord injury. Biomaterials 2011; 33:1618-26. [PMID: 22130565 DOI: 10.1016/j.biomaterials.2011.11.002] [Citation(s) in RCA: 88] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2011] [Accepted: 11/03/2011] [Indexed: 11/21/2022]
Abstract
Therapeutic strategies following spinal cord injury must address the multiple barriers that limit regeneration. Multiple channel bridges have been developed that stabilize the injury following implantation and provide physical guidance for regenerating axons. These bridges have now been employed as a vehicle for localized delivery of lentivirus. Implantation of lentivirus loaded multiple channel bridges produced transgene expression that persisted for at least 4 weeks. Expression was maximal at the implant at the earliest time point, and decreased with increasing time of implantation, as well as rostral and caudal to the bridge. Immunohistochemical staining indicated transduction of macrophages, Schwann cells, fibroblasts, and astrocytes within the bridge and adjacent tissue. Subsequently, the delivery of lentivirus encoding the neurotrophic factors NT-3 or BDNF significantly increased the extent of axonal growth into the bridge relative to empty scaffolds. In addition to promoting axon growth, the induced expression of neurotrophic factors led to myelination of axons within the channels of the bridge, where the number of myelinated axons was significantly enhanced relative to control. Combining gene delivery with biomaterials to provide physical guidance and create a permissive environment can provide a platform to enhance axonal growth and promote regeneration.
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103
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Chen X, Yang Y, Yao J, Lin W, Li Y, Chen Y, Gao Y, Yang Y, Gu X, Wang X. Bone marrow stromal cells-loaded chitosan conduits promote repair of complete transection injury in rat spinal cord. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2011; 22:2347-2356. [PMID: 21792742 DOI: 10.1007/s10856-011-4401-9] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2010] [Accepted: 07/14/2011] [Indexed: 05/31/2023]
Abstract
In this study, a chitosan conduit loaded with bone marrow stromal cells (BMSCs) was developed to bridge the gap in the transected spinal cord of adult rats, and the nerve repair outcomes were evaluated by functional and histological techniques at 12 weeks after implantation. As compared to chitosan conduits alone, incorporation of BMSCs within chitosan conduits yielded additional improving effects on nerve regeneration and function restoration. The measurements with the Basso, Beattie and Bresnahan locomotor rating scale or of motor evoked potentials indicated that motor functional recovery was enhanced; retrograde tracing confirmed that the ascending tract was regenerated and the neural pathway was established; and histological analyses revealed that axon growth and remyelination in the regenerated nerve was promoted. The three-dimensional reconstruction showed that the chitosan conduit loaded with BMSCs significantly reduced the spinal cord cavity volume at the injured site. Taken together, the results collectively suggest that implantation with BMSCs-loaded chitosan conduits may become a promising approach to the repair of spinal cord injury.
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Affiliation(s)
- Xue Chen
- Department of Histology and Embryology, Medical College, Nantong University, Nantong, 226001, Jiangsu, China
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104
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Kubinová Š, Horák D, Hejčl A, Plichta Z, Kotek J, Syková E. Highly superporous cholesterol-modified poly(2-hydroxyethyl methacrylate) scaffolds for spinal cord injury repair. J Biomed Mater Res A 2011; 99:618-29. [DOI: 10.1002/jbm.a.33221] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2011] [Accepted: 07/21/2011] [Indexed: 11/12/2022]
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105
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Zhang YQ, He LM, Xing B, Zeng X, Zeng CG, Zhang W, Quan DP, Zeng YS. Neurotrophin-3 Gene-Modified Schwann Cells Promote TrkC Gene-Modified Mesenchymal Stem Cells to Differentiate into Neuron-Like Cells in Poly(Lactic-Acid-Co-Glycolic Acid) Multiple-Channel Conduit. Cells Tissues Organs 2011; 195:313-22. [DOI: 10.1159/000327724] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/23/2011] [Indexed: 11/19/2022] Open
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106
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Chen BK, Knight AM, Madigan NN, Gross L, Dadsetan M, Nesbitt JJ, Rooney GE, Currier BL, Yaszemski MJ, Spinner RJ, Windebank AJ. Comparison of polymer scaffolds in rat spinal cord: a step toward quantitative assessment of combinatorial approaches to spinal cord repair. Biomaterials 2011; 32:8077-86. [PMID: 21803415 DOI: 10.1016/j.biomaterials.2011.07.029] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2011] [Accepted: 07/08/2011] [Indexed: 01/10/2023]
Abstract
The transected rat thoracic (T(9/10)) spinal cord model is a platform for quantitatively comparing biodegradable polymer scaffolds. Schwann cell-loaded scaffolds constructed from poly (lactic co-glycolic acid) (PLGA), poly(ɛ-caprolactone fumarate) (PCLF), oligo(polyethylene glycol) fumarate (OPF) hydrogel or positively charged OPF (OPF+) hydrogel were implanted into the model. We demonstrated that the mechanical properties (3-point bending and stiffness) of OPF and OPF + hydrogels closely resembled rat spinal cord. After one month, tissues were harvested and analyzed by morphometry of neurofilament-stained sections at rostral, midlevel, and caudal scaffold. All polymers supported axonal growth. Significantly higher numbers of axons were found in PCLF (P < 0.01) and OPF+ (P < 0.05) groups, compared to that of the PLGA group. OPF + polymers showed more centrally distributed axonal regeneration within the channels while other polymers (PLGA, PCLF and OPF) tended to show more evenly dispersed axons within the channels. The centralized distribution was associated with significantly more axons regenerating (P < 0.05). Volume of scar and cyst rostral and caudal to the implanted scaffold was measured and compared. There were significantly smaller cyst volumes in PLGA compared to PCLF groups. The model provides a quantitative basis for assessing individual and combined tissue engineering strategies.
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Affiliation(s)
- Bingkun K Chen
- Mayo Clinic College of Medicine, Department of Neurology, Mayo Clinic, Rochester, MN 55905, USA
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107
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Saberi H, Firouzi M, Habibi Z, Moshayedi P, Aghayan HR, Arjmand B, Hosseini K, Razavi HE, Yekaninejad MS. Safety of intramedullary Schwann cell transplantation for postrehabilitation spinal cord injuries: 2-year follow-up of 33 cases. J Neurosurg Spine 2011; 15:515-25. [PMID: 21800956 DOI: 10.3171/2011.6.spine10917] [Citation(s) in RCA: 89] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECT Many experimental studies on spinal cord injuries (SCIs) support behavioral improvement after Schwann cell treatment. This study was conducted to evaluate safety issues 2 years after intramedullary Schwann cell transplantation in 33 consecutively selected patients with SCI. METHODS Of 356 patients with SCIs who had completed at least 6 months of a conventional rehabilitation program and who were screened for the study criteria, 33 were enrolled. After giving their informed consent, they volunteered for participation. They underwent sural nerve harvesting and intramedullary injection of a processed Schwann cell solution. Outcome assessments included a general health questionnaire, neurological examination, and functional recordings in terms of American Spinal Injury Association (ASIA) and Functional Independence Measure scoring, which were documented by independent observers. There were 24 patients with thoracic and 9 with cervical injuries. Sixteen patients were categorized in ASIA Grade A, and the 17 remaining participants had ASIA Grade B. RESULTS There were no cases of deep infection, and the follow-up MR imaging studies obtained at 2 years did not reveal any deformity related to the procedure. There was no case of permanent neurological worsening or any infectious or viral complications. No new increment in syrinx size or abnormal tissue and/or tumor formation were observed on contrast-enhanced MR imaging studies performed 2 years after the treatment. CONCLUSIONS Preliminary results, especially in terms of safety, seem to be promising, paving the way for future cell therapy trials.
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Affiliation(s)
- Hooshang Saberi
- Department of Neurosurgery, Imam Khomeini Hospital, Tehran University of Medical Sciences, Tehran, Iran.
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108
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Ulery BD, Nair LS, Laurencin CT. Biomedical Applications of Biodegradable Polymers. JOURNAL OF POLYMER SCIENCE. PART B, POLYMER PHYSICS 2011; 49:832-864. [PMID: 21769165 PMCID: PMC3136871 DOI: 10.1002/polb.22259] [Citation(s) in RCA: 1193] [Impact Index Per Article: 91.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Utilization of polymers as biomaterials has greatly impacted the advancement of modern medicine. Specifically, polymeric biomaterials that are biodegradable provide the significant advantage of being able to be broken down and removed after they have served their function. Applications are wide ranging with degradable polymers being used clinically as surgical sutures and implants. In order to fit functional demand, materials with desired physical, chemical, biological, biomechanical and degradation properties must be selected. Fortunately, a wide range of natural and synthetic degradable polymers has been investigated for biomedical applications with novel materials constantly being developed to meet new challenges. This review summarizes the most recent advances in the field over the past 4 years, specifically highlighting new and interesting discoveries in tissue engineering and drug delivery applications.
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Affiliation(s)
- Bret D. Ulery
- Department of Orthopaedic Surgery, New England Musculoskeletal Institute, University of Connecticut Health Center, Farmington, Connecticut 06030
- Institute of Regenerative Engineering, University of Connecticut Health Center, Farmington, Connecticut 06030
| | - Lakshmi S. Nair
- Department of Orthopaedic Surgery, New England Musculoskeletal Institute, University of Connecticut Health Center, Farmington, Connecticut 06030
- Institute of Regenerative Engineering, University of Connecticut Health Center, Farmington, Connecticut 06030
- Department of Chemical, Materials & Biomolecular Engineering, University of Connecticut, Storrs, Connecticut 06268
| | - Cato T. Laurencin
- Department of Orthopaedic Surgery, New England Musculoskeletal Institute, University of Connecticut Health Center, Farmington, Connecticut 06030
- Institute of Regenerative Engineering, University of Connecticut Health Center, Farmington, Connecticut 06030
- Department of Chemical, Materials & Biomolecular Engineering, University of Connecticut, Storrs, Connecticut 06268
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109
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Krick K, Tammia M, Martin R, Höke A, Mao HQ. Signaling cue presentation and cell delivery to promote nerve regeneration. Curr Opin Biotechnol 2011; 22:741-6. [PMID: 21531127 DOI: 10.1016/j.copbio.2011.04.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2011] [Accepted: 04/01/2011] [Indexed: 01/09/2023]
Abstract
Limitations in current nerve regeneration techniques have stimulated the development of various approaches to mimic the extrinsic cues available in the natural nerve regeneration environment. Biomaterials approaches modulate the microenvironment of a regenerating nerve through tailored presentation of signaling molecules, creating physical and biochemical guidance cues to direct axonal regrowth across nerve lesion sites. Cell-based approaches center on increasing the neurotrophic support, adhesion guidance and myelination capacity of Schwann cells and other alternative cell types to enhance nerve regrowth and functional recovery. Recent advances in presenting directional guidance cues in nerve guidance conduits and improving the regenerative outcomes of cell delivery provide inspirations to engineering the next generation of nerve repair solutions.
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Affiliation(s)
- Kellin Krick
- Department of Biomedical Engineering, Johns Hopkins School of Medicine, Baltimore, MD, USA
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110
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Fan J, Zhang H, He J, Xiao Z, Chen B, Xiaodan J, Dai J, Xu R. Neural regrowth induced by PLGA nerve conduits and neurotrophin-3 in rats with complete spinal cord transection. J Biomed Mater Res B Appl Biomater 2011; 97:271-7. [DOI: 10.1002/jbm.b.31810] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2010] [Revised: 11/16/2010] [Accepted: 11/25/2010] [Indexed: 11/09/2022]
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Zhang J, Zhao F, Wu G, Li Y, Jin X. Functional and histological improvement of the injured spinal cord following transplantation of Schwann cells transfected with NRG1 gene. Anat Rec (Hoboken) 2011; 293:1933-46. [PMID: 20734425 DOI: 10.1002/ar.21223] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
In this study, we implanted Schwann cells (SCs) transfected with Neuregulin 1 (NRG1) gene into rats with hemisection spinal cord injury, determined its effects on the repair of spinal cord injury and investigated the underlying mechanisms. Primary SCs were cultured, purified, and transfected with NRG1 gene. SCs and SCs transfected with NRG1 gene were implanted, respectively, into rats with hemisection spinal cord injury. Behavior, imaging, electrophysiology, and immuno-histological analyses were performed to evaluate the effect of NRG1 gene-transfected SCs on the repair of spinal cord injury. In vitro studies showed that NRG1 protein was highly expressed in SCs transfected with NRG1 gene. In addition, the receptors for NRG1, ErbB2, and ErbB4, were upregulated in a time-dependent manner. NRG1-transfected SCs secreted large amount of NRG1 proteins in vivo, which efficiently promoted the expression of ErbB2 and ErbB4 in the neurons and neuroglia cells. Moreover, the number of NSE- and GFAP-positive cells was increased. After cell transplantation, many transplanted cells survived and migrated to the areas with spinal cord injuries. The injuries were recovered in all the experimental groups, but the most significant recovery was observed in the group of rats implanted with SCs transfected with NRG1 gene. We conclude that NRG1-transfected SCs can significantly increase the effect on the repair of spinal cord injury. This repair effect is achieved via the upregulation of ErbB receptor in the target cells, increased proliferation of glial cells, and protection of neurons from apoptosis.
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Affiliation(s)
- Jifei Zhang
- Department of Histoembryology, Medical College of Mudanjiang, Mudanjiang City, Heilongjiang Province, China
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112
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Rooney GE, Knight AM, Madigan NN, Gross L, Chen B, Giraldo CV, Seo S, Nesbitt JJ, Dadsetan M, Yaszemski MJ, Windebank AJ. Sustained delivery of dibutyryl cyclic adenosine monophosphate to the transected spinal cord via oligo [(polyethylene glycol) fumarate] hydrogels. Tissue Eng Part A 2011; 17:1287-302. [PMID: 21198413 DOI: 10.1089/ten.tea.2010.0396] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
This study describes the use of oligo [(polyethylene glycol) fumarate] (OPF) hydrogel scaffolds as vehicles for sustained delivery of dibutyryl cyclic adenosine monophosphate (dbcAMP) to the transected spinal cord. dbcAMP was encapsulated in poly(lactic-co-glycolic acid) (PLGA) microspheres, which were embedded within the scaffolds architecture. Functionality of the released dbcAMP was assessed using neurite outgrowth assays in PC12 cells and by delivery to the transected spinal cord within OPF seven channel scaffolds, which had been loaded with Schwann cells or mesenchymal stem cells (MSCs). Our results showed that encapsulation of dbcAMP in microspheres lead to prolonged release and continued functionality in vitro. These microspheres were then successfully incorporated into OPF scaffolds and implanted in the transected thoracic spinal cord. Sustained delivery of dbcAMP inhibited axonal regeneration in the presence of Schwann cells but rescued MSC-induced inhibition of axonal regeneration. dbcAMP was also shown to reduce capillary formation in the presence of MSCs, which was coupled with significant functional improvements. Our findings demonstrate the feasibility of incorporating PLGA microsphere technology for spinal cord transection studies. It represents a novel sustained delivery mechanism within the transected spinal cord and provides a platform for potential delivery of other therapeutic agents.
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Affiliation(s)
- Gemma E Rooney
- Department of Neurology, Mayo Clinic College of Medicine, Rochester, Minnesota, USA
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113
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Development of complete thoracic spinal cord transection model in rats for delayed transplantation of stem cells. Spine (Phila Pa 1976) 2011; 36:E155-63. [PMID: 21124262 DOI: 10.1097/brs.0b013e3181d8b92a] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
STUDY DESIGN In vivo study of a rat spinal cord injury model. OBJECTIVES To develop complete transection model of thoracic spinal cord using a polymer sheet and a microtube relevant for delayed transplantation of stem cells. SUMMARY OF BACKGROUND DATA Stem cell transplantation for the regeneration of spinal cord injuries has used animal models. However, current models suffer from inflammation and leakage, which lessens their usefulness in studying delayed stem cell transplantation. METHODS Thoracic spinal cord at T9 level of adult Sprague-Dawley rats was exposed and a 50:50 sheet of poly(D,L-lactic-coglycolic acid) was inserted, exposed spinal cord was completely transected, and collagen was filled between the gap between the proximal and distal stumps of transected spinal cord. A microtube was placed and fixed between the polymer surfaces facing each other. Behavior testing, magnetic resonance imaging, and myelography were performed to characterize the new complete transection with a gap formation and polymer insertion (GAP) model and to compare the GAP model with the control models. Human mesenchymal stem cells (hMSCs) were transplanted into 3 models and immunohistochemistry and western blot were performed. RESULTS The inserted poly(D,L-lactic-coglycolic acid) sheet was completely disappeared 10 weeks after operation, but the inserted microtube remained firmly fixed in its original position. Myelography of the GAP model showed no leakage of contrast medium around the injured spinal cord, whereas magnetic resonance imaging of the severe contusion and simple transection models showed some leakage of contrast medium. Immunohistochemistry and western blot after hMSCs transplantation indicated that transplanted hMSCs survived and migrated well in the GAP model, and the deposition of inflammatory cells in GAP model was less than a simple transection model or severe contusion model. CONCLUSION The developed GAP model is more relevant for delayed transplantation of stem cells for the study of regeneration of spinal cord injury of rats.
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114
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Han Q, Jin W, Xiao Z, Ni H, Wang J, Kong J, Wu J, Liang W, Chen L, Zhao Y, Chen B, Dai J. The promotion of neural regeneration in an extreme rat spinal cord injury model using a collagen scaffold containing a collagen binding neuroprotective protein and an EGFR neutralizing antibody. Biomaterials 2011; 31:9212-20. [PMID: 20869112 DOI: 10.1016/j.biomaterials.2010.08.040] [Citation(s) in RCA: 97] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2010] [Accepted: 08/19/2010] [Indexed: 10/19/2022]
Abstract
In the treatment of spinal cord injury, implantation of scaffolding biomaterials and the addition of neuroprotective factors will promote neural regeneration. It has been demonstrated in our previous work that linear ordered collagen scaffold (LOCS) will bridge neural regeneration after the injury of spinal cord hemisection, and BDNF fused with a collagen binding domain (CBD-BDNF) can bind to collagen specifically to exert the neuroprotective effect. Besides neuroprotective factors, the lack of axon regeneration of the injured spinal cord has been attributed partially to regeneration inhibitors such as myelin associated proteins and chondroitin sulfate proteoglycans (CSPGs). Epidermal growth factor receptor (EGFR) activation is downstream of the signaling pathways of these inhibitors. Here, the monoclonal antibody, 151IgG that inhibits signaling of EGFR was used to neutralize EGFR. 151IgG was cross-linked to LOCS and CBD-BDNF bound to LOCS to make a triple-functional biomaterial for neural regeneration (bridging, prompting growth and neutralizing growth inhibitors). This triple-functional device was tested in a 6 mm transected SCI model. Results showed that this collagen scaffold with the addition of 151IgG and CBD-BDNF provided effective bridging and stimulation effects for neural regeneration, recovery of electrical transmission of synapses and preventing the formation of glial scars in the extreme transected rat SCI model.
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Affiliation(s)
- Qianqian Han
- Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China
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115
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Gumera C, Rauck B, Wang Y. Materials for central nervous system regeneration: bioactive cues. ACTA ACUST UNITED AC 2011. [DOI: 10.1039/c0jm04335d] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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116
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Liras A. Future research and therapeutic applications of human stem cells: general, regulatory, and bioethical aspects. J Transl Med 2010; 8:131. [PMID: 21143967 PMCID: PMC3014893 DOI: 10.1186/1479-5876-8-131] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2010] [Accepted: 12/10/2010] [Indexed: 12/24/2022] Open
Abstract
There is much to be investigated about the specific characteristics of stem cells and about the efficacy and safety of the new drugs based on this type of cells, both embryonic as adult stem cells, for several therapeutic indications (cardiovascular and ischemic diseases, diabetes, hematopoietic diseases, liver diseases). Along with recent progress in transference of nuclei from human somatic cells, as well as iPSC technology, has allowed availability of lineages of all three germ layers genetically identical to those of the donor patient, which permits safe transplantation of organ-tissue-specific adult stem cells with no immune rejection. The main objective is the need for expansion of stem cell characteristics to maximize stem cell efficacy (i.e. the proper selection of a stem cell) and the efficacy (maximum effect) and safety of stem cell derived drugs. Other considerations to take into account in cell therapy will be the suitability of infrastructure and technical staff, biomaterials, production costs, biobanks, biosecurity, and the biotechnological industry. The general objectives in the area of stem cell research in the next few years, are related to identification of therapeutic targets and potential therapeutic tests, studies of cell differentiation and physiological mechanisms, culture conditions of pluripotent stem cells and efficacy and safety tests for stem cell-based drugs or procedures to be performed in both animal and human models in the corresponding clinical trials. A regulatory framework will be required to ensure patient accessibility to products and governmental assistance for their regulation and control. Bioethical aspects will be required related to the scientific and therapeutic relevance and cost of cryopreservation over time, but specially with respect to embryos which may ultimately be used for scientific uses of research as source of embryonic stem cells, in which case the bioethical conflict may be further aggravated.
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Affiliation(s)
- Antonio Liras
- Department of Physiology, School of Biological Sciences, Complutense University of Madrid, Spain.
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117
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Yucel D, Kose GT, Hasirci V. Tissue Engineered, Guided Nerve Tube Consisting of Aligned Neural Stem Cells and Astrocytes. Biomacromolecules 2010; 11:3584-91. [DOI: 10.1021/bm1010323] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Deniz Yucel
- METU, Central Laboratory, Molecular Biology and Biotechnology R&D Center, METU, BIOMAT, Departments of Biotechnology and Biological Sciences, Biotechnology Research Unit, 06531 Ankara, Turkey, and Department of Genetics and Bioengineering, Yeditepe University, 34755 Istanbul, Turkey
| | - Gamze Torun Kose
- METU, Central Laboratory, Molecular Biology and Biotechnology R&D Center, METU, BIOMAT, Departments of Biotechnology and Biological Sciences, Biotechnology Research Unit, 06531 Ankara, Turkey, and Department of Genetics and Bioengineering, Yeditepe University, 34755 Istanbul, Turkey
| | - Vasif Hasirci
- METU, Central Laboratory, Molecular Biology and Biotechnology R&D Center, METU, BIOMAT, Departments of Biotechnology and Biological Sciences, Biotechnology Research Unit, 06531 Ankara, Turkey, and Department of Genetics and Bioengineering, Yeditepe University, 34755 Istanbul, Turkey
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118
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Hyun JK, Kim HW. Clinical and experimental advances in regeneration of spinal cord injury. J Tissue Eng 2010; 2010:650857. [PMID: 21350645 PMCID: PMC3042682 DOI: 10.4061/2010/650857] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2010] [Accepted: 10/18/2010] [Indexed: 01/26/2023] Open
Abstract
Spinal cord injury (SCI) is one of the major disabilities dealt with in clinical rehabilitation settings and is multifactorial in that the patients suffer from motor and sensory impairments as well as many other complications throughout their lifetimes. Many clinical trials have been documented during the last two decades to restore damaged spinal cords. However, only a few pharmacological therapies used in clinical settings which still have only limited effects on the regeneration, recovery speed, or retraining of the spinal cord. In this paper, we will introduce recent clinical trials, which performed pharmacological treatments and cell transplantations for patients with SCI, and evaluate recent in vivo studies for the regeneration of injured spinal cord, including stem-cell transplantation, application of neurotrophic factors and suppressor of inhibiting factors, development of biomaterial scaffolds and delivery systems, rehabilitation, and the combinations of these therapies to evaluate what can be appropriately applied in the future to the patients with SCI.
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Affiliation(s)
- Jung Keun Hyun
- Department of Nanobiomedical Science and WCU Nanobiomedical Science Research Center, Dankook University, San 16-5 Anseo-dong, Cheonan, Chungnam 330-715, Republic of Korea
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119
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Madigan NN, McMahon S, O'Brien T, Yaszemski MJ, Windebank AJ. Current tissue engineering and novel therapeutic approaches to axonal regeneration following spinal cord injury using polymer scaffolds. Respir Physiol Neurobiol 2009; 169:183-99. [PMID: 19737633 DOI: 10.1016/j.resp.2009.08.015] [Citation(s) in RCA: 117] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2009] [Revised: 08/25/2009] [Accepted: 08/29/2009] [Indexed: 12/19/2022]
Abstract
This review highlights current tissue engineering and novel therapeutic approaches to axonal regeneration following spinal cord injury. The concept of developing 3-dimensional polymer scaffolds for placement into a spinal cord transection model has recently been more extensively explored as a solution for restoring neurologic function after injury. Given the patient morbidity associated with respiratory compromise, the discrete tracts in the spinal cord conveying innervation for breathing represent an important and achievable therapeutic target. The aim is to derive new neuronal tissue from the surrounding, healthy cord that will be guided by the polymer implant through the injured area to make functional reconnections. A variety of naturally derived and synthetic biomaterial polymers have been developed for placement in the injured spinal cord. Axonal growth is supported by inherent properties of the selected polymer, the architecture of the scaffold, permissive microstructures such as pores, grooves or polymer fibres, and surface modifications to provide improved adherence and growth directionality. Structural support of axonal regeneration is combined with integrated polymeric and cellular delivery systems for therapeutic drugs and for neurotrophic molecules to regionalize growth of specific nerve populations.
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