1
|
Human umbilical cord mesenchymal stem cells-derived extracellular vesicles facilitate the repair of spinal cord injury via the miR-29b-3p/PTEN/Akt/mTOR axis. Cell Death Discov 2021; 7:212. [PMID: 34381025 PMCID: PMC8357833 DOI: 10.1038/s41420-021-00572-3] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 06/15/2021] [Accepted: 07/07/2021] [Indexed: 01/08/2023] Open
Abstract
Spinal cord injury (SCI) is a salient traumatic disease that often leads to permanent disability, and motor and sensory impairments. Human umbilical cord mesenchymal stem cells (HucMSCs) have a wide application prospect in the treatment of SCI. This study explored the repair effect of HucMSCs-derived extracellular vesicles (HucMSCs-EVs) on SCI. HucMSCs and HucMSCs-EVs were cultured and identified. The rat model of SCI was established, and SCI rats were treated with HucMSCs-EVs. The motor function of SCI rats and morphology of spinal cord tissues were evaluated. Levels of NeuN, GFAP, and NF200 in spinal cord tissues were detected and cell apoptosis was measured. SCI rats were treated with EVs extracted from miR-29b-3p inhibitor-transfected HucMSCs. The downstream gene and pathway of miR-29b-3p were examined. HucMSCs-EVs-treated rats showed obvious motor function recovery and reduced necrosis, nuclear pyknosis, and cavity. HucMSCs-EVs alleviated spinal cord neuronal injury. miR-29b-3p was poorly expressed in SCI tissues, but highly expressed in EVs and SCI rats treated with EVs. miR-29b-3p targeted PTEN. Inhibition of miR-29b-3p or overexpression of PTEN reversed the repair effect of EVs on SCI. EVs activated the AKT/mTOR pathway via the miR-29b-3p/PTEN. In conclusion, HucMSCs-EVs reduced pathological changes, improved motor function, and promoted nerve function repair in SCI rats via the miR-29b-3p/PTEN/Akt/mTOR axis.
Collapse
|
2
|
Johnson LDV, Pickard MR, Johnson WEB. The Comparative Effects of Mesenchymal Stem Cell Transplantation Therapy for Spinal Cord Injury in Humans and Animal Models: A Systematic Review and Meta-Analysis. BIOLOGY 2021; 10:biology10030230. [PMID: 33809684 PMCID: PMC8001771 DOI: 10.3390/biology10030230] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/13/2021] [Revised: 02/28/2021] [Accepted: 03/12/2021] [Indexed: 12/17/2022]
Abstract
Animal models have been used in preclinical research to examine potential new treatments for spinal cord injury (SCI), including mesenchymal stem cell (MSC) transplantation. MSC transplants have been studied in early human trials. Whether the animal models represent the human studies is unclear. This systematic review and meta-analysis has examined the effects of MSC transplants in human and animal studies. Following searches of PubMed, Clinical Trials and the Cochrane Library, published papers were screened, and data were extracted and analysed. MSC transplantation was associated with significantly improved motor and sensory function in humans, and significantly increased locomotor function in animals. However, there are discrepancies between the studies of human participants and animal models, including timing of MSC transplant post-injury and source of MSCs. Additionally, difficulty in the comparison of functional outcome measures across species limits the predictive nature of the animal research. These findings have been summarised, and recommendations for further research are discussed to better enable the translation of animal models to MSC-based human clinical therapy.
Collapse
Affiliation(s)
- Louis D. V. Johnson
- Chester Medical School, University of Chester, Chester CH1 4BJ, UK
- Correspondence: (L.D.V.J.); (W.E.B.J.); Tel.: +44-7557-353206 (L.D.V.J.); +44-774-5616225 (W.E.B.J.)
| | - Mark R. Pickard
- University Centre Shrewsbury, University of Chester, Shrewsbury SY3 8HQ, UK;
| | - William E. B. Johnson
- Chester Medical School, University of Chester, Chester CH1 4BJ, UK
- University Centre Shrewsbury, University of Chester, Shrewsbury SY3 8HQ, UK;
- Correspondence: (L.D.V.J.); (W.E.B.J.); Tel.: +44-7557-353206 (L.D.V.J.); +44-774-5616225 (W.E.B.J.)
| |
Collapse
|
3
|
Hu XC, Lu YB, Yang YN, Kang XW, Wang YG, Ma B, Xing S. Progress in clinical trials of cell transplantation for the treatment of spinal cord injury: how many questions remain unanswered? Neural Regen Res 2021; 16:405-413. [PMID: 32985458 PMCID: PMC7996007 DOI: 10.4103/1673-5374.293130] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2020] [Revised: 03/17/2020] [Accepted: 04/26/2020] [Indexed: 02/05/2023] Open
Abstract
Spinal cord injury can lead to severe motor, sensory and autonomic nervous dysfunctions. However, there is currently no effective treatment for spinal cord injury. Neural stem cells and progenitor cells, bone marrow mesenchymal stem cells, olfactory ensheathing cells, umbilical cord blood stem cells, adipose stem cells, hematopoietic stem cells, oligodendrocyte precursor cells, macrophages and Schwann cells have been studied as potential treatments for spinal cord injury. These treatments were mainly performed in animals. However, subtle changes in sensory function, nerve root movement and pain cannot be fully investigated with animal studies. Although these cell types have shown excellent safety and effectiveness in various animal models, sufficient evidence of efficacy for clinical translation is still lacking. Cell transplantation should be combined with tissue engineering scaffolds, local drug delivery systems, postoperative adjuvant therapy and physical rehabilitation training as part of a comprehensive treatment plan to provide the possibility for patients with SCI to return to normal life. This review summarizes and analyzes the clinical trials of cell transplantation therapy in spinal cord injury, with the aim of providing a rational foundation for the development of clinical treatments for spinal cord injury.
Collapse
Affiliation(s)
- Xu-Chang Hu
- Key Laboratory of Bone and Joint Diseases Research of Gansu Province, Department of Orthopedics, Lanzhou University Second Hospital, Lanzhou, Gansu Province, China
| | - Yu-Bao Lu
- Second Clinical Medical College, Lanzhou University, Lanzhou, Gansu Province, China
| | - Yong-Na Yang
- Department of Neurology, The First People's Hospital of Lanzhou City, Lanzhou, Gansu Province, China
| | - Xue-Wen Kang
- Key Laboratory of Bone and Joint Diseases Research of Gansu Province, Department of Orthopedics, Lanzhou University Second Hospital, Lanzhou, Gansu Province, China
| | - Yong-Gang Wang
- Key Laboratory of Bone and Joint Diseases Research of Gansu Province, Department of Orthopedics, Lanzhou University Second Hospital, Lanzhou, Gansu Province, China
| | - Bing Ma
- Key Laboratory of Bone and Joint Diseases Research of Gansu Province, Department of Orthopedics, Lanzhou University Second Hospital, Lanzhou, Gansu Province, China
| | - Shuai Xing
- Key Laboratory of Bone and Joint Diseases Research of Gansu Province, Department of Orthopedics, Lanzhou University Second Hospital, Lanzhou, Gansu Province, China
| |
Collapse
|
4
|
Shehadi JA, Elzein SM, Beery P, Spalding MC, Pershing M. Combined administration of platelet rich plasma and autologous bone marrow aspirate concentrate for spinal cord injury: a descriptive case series. Neural Regen Res 2021; 16:362-366. [PMID: 32859799 PMCID: PMC7896202 DOI: 10.4103/1673-5374.290903] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Administration of platelet rich plasma (PRP) and bone marrow aspirate concentrate (BMAC) has shown some promise in the treatment of neurological conditions; however, there is limited information on combined administration. As such, the purpose of this study was to assess safety and functional outcomes for patients administered combined autologous PRP and BMAC for spinal cord injury (SCI). This retrospective case series included seven patients who received combined treatment of autologous PRP and BMAC via intravenous and intrathecal administration as salvage therapy for SCI. Patients were reviewed for adverse reactions and clinical outcomes using the Oswestry Disability Index (ODI) for up to 1 year, as permitted by availability of follow-up data. Injury levels ranged from C3 through T11, and elapsed time between injury and salvage therapy ranged from 2.4 months to 6.2 years. Post-procedure complications were mild and rare, consisting only of self-limited headache and subjective memory impairment in one patient. Four patients experienced severe disability prior to PRP combined with BMAC injection, as evidenced by high (> 48/100) Oswestry Disability Index scores. Longitudinal Oswestry Disability Index scores for two patients with incomplete SCI at C6 and C7, both of whom had cervical spine injuries, demonstrated a decrease of 28–40% following salvage therapy, representing an improvement from severe to minimal disability. In conclusion, intrathecal/intravenous co-administration of PRP and BMAC resulted in no significant complications and may have had some clinical benefits. Larger clinical studies are needed to further test this method of treatment for patients with SCI who otherwise have limited meaningful treatment options. This study was reviewed and approved by the OhioHealth Institutional Review Board (IRB No. 1204946) on May 16, 2018.
Collapse
Affiliation(s)
- Joseph A Shehadi
- Section of Neurosurgery at OhioHealth Grant Medical Center, Cedar Stem Cell Institute, Columbus, OH, USA
| | - Steven M Elzein
- The Ohio State University College of Medicine, Columbus, OH, USA
| | - Paul Beery
- Division of Trauma and Acute Care Surgery, OhioHealth Grant Medical Center, Columbus, OH, USA
| | - M Chance Spalding
- Division of Trauma and Acute Care Surgery, OhioHealth Grant Medical Center, Columbus, OH, USA
| | | |
Collapse
|
5
|
Yu T, Zhao C, Hou S, Zhou W, Wang B, Chen Y. Exosomes secreted from miRNA-29b-modified mesenchymal stem cells repaired spinal cord injury in rats. ACTA ACUST UNITED AC 2019; 52:e8735. [PMID: 31826179 PMCID: PMC6903804 DOI: 10.1590/1414-431x20198735] [Citation(s) in RCA: 97] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Accepted: 10/14/2019] [Indexed: 12/14/2022]
Abstract
Exosomes, a kind of extracellular vesicle, are promising therapeutic agents for spinal cord injury (SCI). This article aimed to investigate effects of exosomes secreted from miRNA-29b-modified bone marrow mesenchymal stem cells (BMSCs) on SCI. Exosomes were extracted from BMSCs transfected with miRNA-29b or negative control (miR NC). SCI rats were injected intravenously with exosomes (control exosomes, miRNA-29b exosomes) and BMSCs (miR NC, miRNA-29b) through the tail vein. The expression of miRNA-29b in spinal cord tissues of SCI rats was detected by qRT-PCR. The hind limb motor function was evaluated by Basso Beattie Bresnahan (BBB) score. The histopathological damage and neuronal regeneration in spinal cord tissues was observed by HE staining and immunohistochemistry, respectively. The injection of miRNA-29b exosomes and miRNA-29b BMSCs both significantly increased the expression of miRNA-29b in spinal cord tissues of SCI rats (P<0.05). Compared with SCI rats, rats in the miRNA-29b exosomes and the miRNA-29b groups exhibited improved SCI, including increased BBB score, NF200 and GAP-43 positive neurons, as well as decreased contractile nerve cell numbers and GFAP positive neurons (all P<0.05). The relieving degree of SCI was significantly higher in the miRNA-29b exosomes group than in the miRNA-29b BMSCs group (P<0.05). Exosomes secreted from miRNA-29b-modified BMSCs were effective in the repair of SCI in rats.
Collapse
Affiliation(s)
- Tao Yu
- Department of Spinal Surgery, Qilu Hospitial of ShanDong University, Jinan, Shandong, China.,Department of Orthopedics, Liaocheng People's Hospitial, Liaocheng, Shandong, China
| | - Cunju Zhao
- Department of Spinal Surgery, Qilu Hospitial of ShanDong University, Jinan, Shandong, China.,Department of Orthopedics, Liaocheng People's Hospitial, Liaocheng, Shandong, China
| | - Shouzhi Hou
- Department of Radiology, Liaocheng People's Hospitial, Liaocheng, Shandong, China
| | - Weijie Zhou
- Department of Orthopedics, Liaocheng People's Hospitial, Liaocheng, Shandong, China
| | - Baoxin Wang
- Department of Orthopedics, Liaocheng People's Hospitial, Liaocheng, Shandong, China
| | - Yunzhen Chen
- Department of Spinal Surgery, Qilu Hospitial of ShanDong University, Jinan, Shandong, China
| |
Collapse
|
6
|
Hakim R, Covacu R, Zachariadis V, Frostell A, Sankavaram SR, Brundin L, Svensson M. Mesenchymal stem cells transplanted into spinal cord injury adopt immune cell-like characteristics. Stem Cell Res Ther 2019; 10:115. [PMID: 30944028 PMCID: PMC6448247 DOI: 10.1186/s13287-019-1218-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2018] [Revised: 02/27/2019] [Accepted: 03/20/2019] [Indexed: 02/06/2023] Open
Abstract
Background Mesenchymal stem cells (MSCs) and their cellular response to various stimuli have been characterized in great detail in culture conditions. In contrast, the cellular response of MSCs in an in vivo setting is still uncharted territory. In this study, we investigated the cellular response of MSCs following transplantation into spinal cord injury (SCI). Methods Mouse bone marrow-derived MSCs were transplanted 24 h following severe contusion SCI in mice. As controls, MSCs transplanted to the uninjured spinal cord and non-transplanted MSCs were used. At 7 days post transplantation, the MSCs were isolated from the SCI, and their global transcriptional changes, survival, differentiation, proliferation, apoptosis, and phenotypes were investigated using RNA sequencing, immunohistochemistry, and flow cytometry. Results MSCs transplanted into SCI downregulated genes related to cell-cycle regulation/progression, DNA metabolic/biosynthetic process, and DNA repair and upregulated genes related to immune system response, cytokine production/response, response to stress/stimuli, signal transduction and signaling pathways, apoptosis, and phagocytosis/endocytosis. MSCs maintained their surface expression of Sca1 and CD29 but upregulated expression of CD45 following transplantation. Transplanted MSCs maintained their surface expression of MHC-I but upregulated surface expression of MHC-II. Transplanted MSCs survived and proliferated to a low extent, did not express Caspase-3, and did not differentiate into neurons or astrocytes. Conclusion MSCs transplanted into SCI upregulate expression of CD45 and MHC-II and expression of genes related to cytokine production, phagocytosis/endocytosis, and immune cells/response and thereby adopt immune cell-like characteristics within the recipient. Electronic supplementary material The online version of this article (10.1186/s13287-019-1218-9) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Ramil Hakim
- Department of Neurology, Karolinska University Hospital, 17176, Stockholm, Sweden.,Department of Clinical Neuroscience, Karolinska Institutet, 17176, Stockholm, Sweden.,BioClinicum, Karolinska University Hospital, Solnavägen 30, Solna, 171 64, Stockholm, Sweden
| | - Ruxandra Covacu
- Department of Neurology, Karolinska University Hospital, 17176, Stockholm, Sweden.,Center for Molecular Medicine, Karolinska Institutet, 17176, Stockholm, Sweden.,Department of Clinical Neuroscience, Karolinska Institutet, 17176, Stockholm, Sweden
| | - Vasilios Zachariadis
- Department of Oncology and Pathology, Karolinska Institutet, 17176, Stockholm, Sweden
| | - Arvid Frostell
- Department of Clinical Neuroscience, Karolinska Institutet, 17176, Stockholm, Sweden.,BioClinicum, Karolinska University Hospital, Solnavägen 30, Solna, 171 64, Stockholm, Sweden.,Department of Neurosurgery, Karolinska University Hospital, 17176, Stockholm, Sweden
| | - Sreenivasa Raghavan Sankavaram
- Center for Molecular Medicine, Karolinska Institutet, 17176, Stockholm, Sweden.,Department of Clinical Neuroscience, Karolinska Institutet, 17176, Stockholm, Sweden
| | - Lou Brundin
- Department of Neurology, Karolinska University Hospital, 17176, Stockholm, Sweden. .,Department of Clinical Neuroscience, Karolinska Institutet, 17176, Stockholm, Sweden. .,BioClinicum, Karolinska University Hospital, Solnavägen 30, Solna, 171 64, Stockholm, Sweden.
| | - Mikael Svensson
- Department of Clinical Neuroscience, Karolinska Institutet, 17176, Stockholm, Sweden.,BioClinicum, Karolinska University Hospital, Solnavägen 30, Solna, 171 64, Stockholm, Sweden.,Department of Neurosurgery, Karolinska University Hospital, 17176, Stockholm, Sweden
| |
Collapse
|
7
|
Karaoz E, Tepekoy F, Yilmaz I, Subasi C, Kabatas S. Reduction of Inflammation and Enhancement of Motility after Pancreatic Islet Derived Stem Cell Transplantation Following Spinal Cord Injury. J Korean Neurosurg Soc 2019; 62:153-165. [PMID: 30840970 PMCID: PMC6411578 DOI: 10.3340/jkns.2018.0035] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Accepted: 06/23/2018] [Indexed: 01/01/2023] Open
Abstract
Objective Spinal cord injury (SCI) is a very serious health problem, usually caused by a trauma and accompanied by elevated levels of inflammation indicators. Stem cell-based therapy is promising some valuable strategies for its functional recovery. Nestin-positive progenitor and/or stem cells (SC) isolated from pancreatic islets (PI) show mesenchymal stem cell (MSC) characteristics. For this reason, we aimed to analyze the effects of rat pancreatic islet derived stem cell (rPI-SC) delivery on functional recovery, as well as the levels of inflammation factors following SCI.
Methods rPI-SCs were isolated, cultured and their MSC characteristics were determined through flow cytometry and immunofluorescence analysis. The experimental rat population was divided into three groups : 1) laminectomy & trauma, 2) laminectomy & trauma & phosphate-buffered saline (PBS), and 3) laminectomy+trauma+SCs. Green fluorescent protein (GFP) labelled rPI-SCs were transplanted into the injured rat spinal cord. Their motilities were evaluated with Basso, Beattie and Bresnahan (BBB) Score. After 4-weeks, spinal cord sections were analyzed for GFP labeled SCs and stained for vimentin, S100β, brain derived neurotrophic factor (BDNF), 2’,3’-cyclic-nucleotide 3'-phosphodiesterase (CNPase), vascular endothelial growth factor (VEGF) and proinflammatory (interleukin [IL]-6, transforming growth factor [TGF]-β, macrophage inflammatory protein [MIP]-2, myeloperoxidase [MPO]) and anti-inflammatory (IL-1 receptor antagonis) factors.
Results rPI-SCs were revealed to display MSC characteristics and express neural and glial cell markers including BDNF, glial fibrillary acidic protein (GFAP), fibronectin, microtubule associated protein-2a,b (MAP2a,b), β3-tubulin and nestin as well as antiinflammatory prostaglandin E2 receptor, EP3. The BBB scores showed significant motor recovery in group 3. GFP-labelled cells were localized on the injury site. In addition, decreased proinflammatory factor levels and increased intensity of anti-inflammatory factors were determined.
Conclusion Transplantation of PI-SCs might be an effective strategy to improve functional recovery following spinal cord trauma.
Collapse
Affiliation(s)
- Erdal Karaoz
- Department of Histology & Embryology, Faculty of Medicine, İstinye University, İstanbul, Turkey.,Center for Stem Cell and Tissue Engineering Research & Practice, İstinye University, İstanbul, Turkey.,Center for Regenerative Medicine and Stem Cell Research & Manufacturing (LivMedCell), İstanbul, Turkey
| | - Filiz Tepekoy
- Department of Histology & Embryology, Faculty of Medicine, İstinye University, İstanbul, Turkey
| | - Irem Yilmaz
- Center for Regenerative Medicine and Stem Cell Research & Manufacturing (LivMedCell), İstanbul, Turkey
| | - Cansu Subasi
- Center for Regenerative Medicine and Stem Cell Research & Manufacturing (LivMedCell), İstanbul, Turkey
| | - Serdar Kabatas
- Neurosurgery Clinic, Gaziosmanpasa Taksim Training and Research Hospital, İstanbul, Turkey
| |
Collapse
|
8
|
Ning GZ, Song WY, Xu H, Zhu RS, Wu QL, Wu Y, Zhu SB, Li JQ, Wang M, Qu ZG, Feng SQ. Bone marrow mesenchymal stem cells stimulated with low-intensity pulsed ultrasound: Better choice of transplantation treatment for spinal cord injury: Treatment for SCI by LIPUS-BMSCs transplantation. CNS Neurosci Ther 2018; 25:496-508. [PMID: 30294904 DOI: 10.1111/cns.13071] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Revised: 09/04/2018] [Accepted: 09/07/2018] [Indexed: 12/19/2022] Open
Abstract
Stem cell transplantation, especially treatment with bone marrow mesenchymal stem cells (BMSCs), has been considered a promising therapy for the locomotor and neurological recovery of spinal cord injury (SCI) patients. However, the clinical benefits of BMSCs transplantation remain limited because of the considerably low viability and inhibitory microenvironment. In our research, low-intensity pulsed ultrasound (LIPUS), which has been widely applied to clinical applications and fundamental research, was employed to improve the properties of BMSCs. The most suitable intensity of LIPUS stimulation was determined. Furthermore, the optimized BMSCs were transplanted into the epicenter of injured spinal cord in rats, which were randomized into four groups: (a) Sham group (n = 10), rats received laminectomy only and the spinal cord remained intact. (b) Injury group (n = 10), rats with contused spinal cord subjected to the microinjection of PBS solution. (c) BMSCs transplantation group (n = 10), rats with contused spinal cord were injected with BMSCs without any priming. (d) LIPUS-BMSCs transplantation group (n = 10), BMSCs stimulated with LIPUS were injected at the injured epicenter after contusion. Rats were then subjected to behavioral tests, immunohistochemistry, and histological observation. It was found that BMSCs stimulated with LIPUS obtained higher cell viability, migration, and neurotrophic factors expression in vitro. The rate of apoptosis remained constant. After transplantation of BMSCs and LIPUS-BMSCs postinjury, locomotor function was significantly improved in LIPUS-BMSCs transplantation group with higher level of brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) in the epicenter, and the expression of neurotrophic receptor was also enhanced. Histological observation demonstrated reduced cavity formation in LIPUS-BMSCs transplantation group when comparing with other groups. The results suggested LIPUS can improve BMSCs viability and neurotrophic factors expression in vitro, and transplantation of LIPUS-BMSCs could promote better functional recovery, indicating possible clinical application for the treatment of SCI.
Collapse
Affiliation(s)
- Guang-Zhi Ning
- Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin, China
| | - Wen-Ye Song
- Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin, China
| | - Hong Xu
- Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin, China.,Department of Orthopedics, Xiaoshan Traditional Chinese Medical Hospital, Hangzhou, China
| | - Ru-Sen Zhu
- Department of Spine Surgery, Tianjin Union Medical Center, Tianjin, China
| | - Qiu-Li Wu
- Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin, China
| | - Yu Wu
- Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin, China
| | - Shi-Bo Zhu
- Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin, China
| | - Ji-Qing Li
- Department of Electronic Engineering, Tianjin University of Science and Technology, Tianjin, China
| | - Man Wang
- Department of Electronic Engineering, Tianjin University of Science and Technology, Tianjin, China
| | - Zhi-Gang Qu
- Department of Electronic Engineering, Tianjin University of Science and Technology, Tianjin, China
| | - Shi-Qing Feng
- Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin, China
| |
Collapse
|
9
|
Turac G, Duruksu G, Karaoz E. The Effect of Recombinant Tyrosine Hydroxylase Expression on the Neurogenic Differentiation Potency of Mesenchymal Stem Cells. Neurospine 2018; 15:42-53. [PMID: 29656620 PMCID: PMC5944638 DOI: 10.14245/ns.1836010.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Revised: 03/14/2018] [Accepted: 03/20/2018] [Indexed: 11/27/2022] Open
Abstract
Objective Tyrosine hydroxylase (TH) is a rate-limiting enzyme in dopamine synthesis, making the enhancement of its activity a target for ensuring sufficient dopamine levels. Rat bone marrow mesenchymal stem cells (rBM-MSCs) are known to synthesize TH after differentiating into neuronal cells through chemical induction, but the effect of its ectopic expression on these cells has not yet been determined. This study investigated the effects of ectopic recombinant TH expression on the stemness characteristics of rBM-MSCs.
Methods After cloning, a cell line with stable TH expression was maintained, and the proliferation, the gene expression profile, and differentiation potential of rBM-MSCs were analyzed. Analysis of the cells showed an increment in the proliferation rate that could be reversed by the neutralization of TH.
Results The constitutive expression of TH in rBM-MSCs was successfully implemented, without significantly affecting their osteogenic and adipogenic differentiation potential. TH expression improved the expression of other neuronal markers, such as glial fibrillary acidic protein, β-tubulin, nestin, and c-Fos, confirming the neurogenic differentiation capacity of the stem cells. The expression of brain-derived neurotrophic factor (BDNF) and ciliary neurotrophic factor (CNTF) significantly increased after the chemical induction of neurogenic differentiation.
Conclusion In this study, the expression of recombinant TH improved the neuroprotective effect of MSCs by upregulating the expression of BDNF and CNTF. Although the neuronal markers were upregulated, the expression of recombinant TH alone in rBM-MSCs was not sufficient for MSCs to differentiate into neurogenic cell lines.
Collapse
Affiliation(s)
- Gizem Turac
- Center for Stem Cell and Gene Therapies Research and Practice, Kocaeli University, İzmit, Kocaeli, Turkey.,Department of Stem Cell, Institute of Health Sciences, Kocaeli University, İzmit, Kocaeli, Turkey
| | - Gokhan Duruksu
- Center for Stem Cell and Gene Therapies Research and Practice, Kocaeli University, İzmit, Kocaeli, Turkey.,Department of Stem Cell, Institute of Health Sciences, Kocaeli University, İzmit, Kocaeli, Turkey
| | - Erdal Karaoz
- Liv Hospital, Center for Regenerative Medicine and Stem Cell Research and Manufacturing, İstanbul, Turkey.,Department of Histology & Embryology, İstinye University, Faculty of Medicine, İstanbul, Turkey
| |
Collapse
|
10
|
Doulames VM, Plant GW. Induced Pluripotent Stem Cell Therapies for Cervical Spinal Cord Injury. Int J Mol Sci 2016; 17:530. [PMID: 27070598 PMCID: PMC4848986 DOI: 10.3390/ijms17040530] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2016] [Revised: 03/17/2016] [Accepted: 03/28/2016] [Indexed: 02/07/2023] Open
Abstract
Cervical-level injuries account for the majority of presented spinal cord injuries (SCIs) to date. Despite the increase in survival rates due to emergency medicine improvements, overall quality of life remains poor, with patients facing variable deficits in respiratory and motor function. Therapies aiming to ameliorate symptoms and restore function, even partially, are urgently needed. Current therapeutic avenues in SCI seek to increase regenerative capacities through trophic and immunomodulatory factors, provide scaffolding to bridge the lesion site and promote regeneration of native axons, and to replace SCI-lost neurons and glia via intraspinal transplantation. Induced pluripotent stem cells (iPSCs) are a clinically viable means to accomplish this; they have no major ethical barriers, sources can be patient-matched and collected using non-invasive methods. In addition, the patient’s own cells can be used to establish a starter population capable of producing multiple cell types. To date, there is only a limited pool of research examining iPSC-derived transplants in SCI—even less research that is specific to cervical injury. The purpose of the review herein is to explore both preclinical and clinical recent advances in iPSC therapies with a detailed focus on cervical spinal cord injury.
Collapse
Affiliation(s)
- Vanessa M Doulames
- Stanford Partnership for Spinal Cord Injury and Repair, Department of Neurosurgery, Stanford University School of Medicine, 265 Campus Drive Stanford, California, CA 94305, USA.
| | - Giles W Plant
- Stanford Partnership for Spinal Cord Injury and Repair, Department of Neurosurgery, Stanford University School of Medicine, 265 Campus Drive Stanford, California, CA 94305, USA.
| |
Collapse
|
11
|
Okay E, Simsek T, Subasi C, Gunes A, Duruksu G, Gurbuz Y, Gacar G, Karaoz E. Cross effects of resveratrol and mesenchymal stem cells on liver regeneration and homing in partially hepatectomized rats. Stem Cell Rev Rep 2016; 11:322-31. [PMID: 25416627 DOI: 10.1007/s12015-014-9572-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
In this study, we examined the effect of preoperatively administered resveratrol (RV) and mesenchymal stem cells (MSCs) on regeneration of partially hepatectomized rat liver. We also evaluated the effect of RV on homing of MSCs. MSCs were isolated from bone marrow and cultured in vitro. Wistar albino rats were randomly divided into four groups. In groups, rats received (1) no treatment, (2) single dose RV, (3) MSCs and (4) RV plus MSCs before partial hepatectomy (PH). Injected MSCs were traced by labeling them with green fluorescent protein, and liver regeneration was determined by comparison of liver weight gain, histological examination and immunohistochemical staining with proliferating cell nuclear antigen (PCNA) for mitotic cells. The expression levels of tumor necrosis factor -alpha (TNF-α), interleukin-6 (IL-6) and hepatocyte growth factor (HGF) were also determined in the parafin sections of liver specimens with immunohistochemical staining. Administration of RV and MSCs separately or together enhanced liver regeneration despite decreasing the TNF-α and IL-6 expression. This positive contribution was probably due to direct raising effect on HGF for RV and HGF expression for MSCs that we demonstrated with immunohistochemical staining. Additionally, RV increased the homing of MSCs in liver probably related to life prolonging effect on MSCs. These results indicate that preoperative RV as well as MSCs application enhances liver regeneration after partial hepatectomy in rats. Paying attention to RV about the effect on liver regeneration and homing of MSCs might be the goal of further investigations.
Collapse
Affiliation(s)
- Erdem Okay
- Department of General Surgery, Kocaeli University School of Medicine, Umuttepe, Kocaeli, Turkey,
| | | | | | | | | | | | | | | |
Collapse
|
12
|
Sabapathy V, Tharion G, Kumar S. Cell Therapy Augments Functional Recovery Subsequent to Spinal Cord Injury under Experimental Conditions. Stem Cells Int 2015; 2015:132172. [PMID: 26240569 PMCID: PMC4512598 DOI: 10.1155/2015/132172] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2014] [Revised: 02/04/2015] [Accepted: 02/05/2015] [Indexed: 02/06/2023] Open
Abstract
The spinal cord injury leads to enervation of normal tissue homeostasis ultimately leading to paralysis. Until now there is no proper cure for the treatment of spinal cord injury. Recently, cell therapy in animal spinal cord injury models has shown some progress of recovery. At present, clinical trials are under progress to evaluate the efficacy of cell transplantation for the treatment of spinal cord injury. Different types of cells such as pluripotent stem cells derived neural cells, mesenchymal stromal cells, neural stem cells, glial cells are being tested in various spinal cord injury models. In this review we highlight both the advances and lacuna in the field of spinal cord injury by discussing epidemiology, pathophysiology, molecular mechanism, and various cell therapy strategies employed in preclinical and clinical injury models and finally we discuss the limitations and ethical issues involved in cell therapy approach for treating spinal cord injury.
Collapse
Affiliation(s)
- Vikram Sabapathy
- Centre for Stem Cell Research, Christian Medical College, Bagayam, Vellore, Tamil Nadu 632002, India
| | - George Tharion
- Department of Physical Medicine and Rehabilitation, Christian Medical College, Vellore, Tamil Nadu 632002, India
| | - Sanjay Kumar
- Centre for Stem Cell Research, Christian Medical College, Bagayam, Vellore, Tamil Nadu 632002, India
| |
Collapse
|
13
|
Chen S, Wu B, Lin J. Effect of intravenous transplantation of bone marrow mesenchymal stem cells on neurotransmitters and synapsins in rats with spinal cord injury. Neural Regen Res 2015; 7:1445-53. [PMID: 25657678 PMCID: PMC4308773 DOI: 10.3969/j.issn.1673-5374.2012.19.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2012] [Accepted: 05/14/2014] [Indexed: 01/19/2023] Open
Abstract
Bone marrow mesenchymal stem cells were isolated, purified and cultured in vitro by Percoll density gradient centrifugation combined with the cell adherence method. Passages 3–5 bone marrow mesenchymal stem cells were transplanted into rats with traumatic spinal cord injury via the caudal vein. Basso-Beattie-Bresnahan scores indicate that neurological function of experimental rats was significantly improved over transplantation time (1–5 weeks). Expressions of choline acetyltransferase, glutamic acid decarboxylase and synapsins in the damaged spinal cord of rats was significantly increased after transplantation, determined by immunofluorescence staining and laser confocal scanning microscopy. Bone marrow mesenchymal stem cells that had migrated into the damaged area of rats in the experimental group began to express choline acetyltransferase, glutamic acid decarboxylase and synapsins, 3 weeks after transplantation. The Basso-Beattie- Bresnahan scores positively correlated with expression of choline acetyltransferase and synapsins. Experimental findings indicate that intravenously transplanted bone marrow mesenchymal stem cells traverse into the damaged spinal cord of rats, promote expression of choline acetyltransferase, glutamic acid decarboxylase and synapsins, and improve nerve function in rats with spinal cord injury.
Collapse
Affiliation(s)
- Shaoqiang Chen
- Department of Human Anatomy and Tissue Embryology, Fujian Medical University, Minhou 350108, Fujian Province, China
| | - Bilian Wu
- Department of Human Anatomy, Fujian Vcational and Technical College of Health, Minhou 350101, Fujian Province, China
| | - Jianhua Lin
- Department of Orthopedics, First Affiliated Hospital of Fujian Medical University, Fuzhou 350005, Fujian Province, China
| |
Collapse
|
14
|
Abstract
Stem cell-based interventions aim to use special regenerative cells (stem cells) to facilitate neuronal function beyond the site of the injury. Many studies involving animal models of spinal cord injury (SCI) suggest that certain stem cell-based therapies may restore function after SCI. Currently, in case of spinal cord injuries, new discoveries with clinical implications have been continuously made in basic stem cell research, and stem cell-based approaches are advancing rapidly toward application in patients. There is a huge base of preclinical evidence in vitro and in animal models which suggests the safety and clinical efficacy of cellular therapies after SCI. Despite this, data from clinical studies is not very encouraging and at times confounding. Here, we have attempted to cover preclinical and clinical evidence base dealing with safety, feasibility and efficacy of cell based interventions after SCI. The limitations of preclinical data and the reasons underlying its failure to translate in a clinical setting are also discussed. Based on the evidence base, it is suggested that a multifactorial approach is required to address this situation. Need for standardized, stringently designed multi-centric clinical trials for obtaining validated proof of evidence is also highlighted.
Collapse
Affiliation(s)
- Harvinder Singh Chhabra
- Spine Service, Indian Spinal Injuries Centre, Vasant Kunj, New Delhi, India,Address for correspondence: Dr. Harvinder Singh Chhabra, Indian Spinal Injuries Centre, Sector C, Vasant Kunj, New Delhi - 110 070, India. E-mail:
| | - Kanchan Sarda
- Spine Service, Indian Spinal Injuries Centre, Vasant Kunj, New Delhi, India
| |
Collapse
|
15
|
The Potential for iPS-Derived Stem Cells as a Therapeutic Strategy for Spinal Cord Injury: Opportunities and Challenges. J Clin Med 2014; 4:37-65. [PMID: 26237017 PMCID: PMC4470238 DOI: 10.3390/jcm4010037] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Accepted: 11/28/2014] [Indexed: 02/07/2023] Open
Abstract
Spinal cord injury (SCI) is a devastating trauma causing long-lasting disability. Although advances have occurred in the last decade in the medical, surgical and rehabilitative treatments of SCI, the therapeutic approaches are still not ideal. The use of cell transplantation as a therapeutic strategy for the treatment of SCI is promising, particularly since it can target cell replacement, neuroprotection and regeneration. Cell therapies for treating SCI are limited due to several translational roadblocks, including ethical and practical concerns regarding cell sources. The use of iPSCs has been particularly attractive, since they avoid the ethical and moral concerns that surround other stem cells. Furthermore, various cell types with potential for application in the treatment of SCI can be created from autologous sources using iPSCs. For applications in SCI, the iPSCs can be differentiated into neural precursor cells, neurons, oligodendrocytes, astrocytes, neural crest cells and mesenchymal stromal cells that can act by replacing lost cells or providing environmental support. Some methods, such as direct reprogramming, are being investigated to reduce tumorigenicity and improve reprogramming efficiencies, which have been some of the issues surrounding the use of iPSCs clinically to date. Recently, iPSCs have entered clinical trials for use in age-related macular degeneration, further supporting their promise for translation in other conditions, including SCI.
Collapse
|
16
|
Martinez AMB, Goulart CDO, Ramalho BDS, Oliveira JT, Almeida FM. Neurotrauma and mesenchymal stem cells treatment: From experimental studies to clinical trials. World J Stem Cells 2014; 6:179-94. [PMID: 24772245 PMCID: PMC3999776 DOI: 10.4252/wjsc.v6.i2.179] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2013] [Revised: 02/26/2014] [Accepted: 03/11/2014] [Indexed: 02/06/2023] Open
Abstract
Mesenchymal stem cell (MSC) therapy has attracted the attention of scientists and clinicians around the world. Basic and pre-clinical experimental studies have highlighted the positive effects of MSC treatment after spinal cord and peripheral nerve injury. These effects are believed to be due to their ability to differentiate into other cell lineages, modulate inflammatory and immunomodulatory responses, reduce cell apoptosis, secrete several neurotrophic factors and respond to tissue injury, among others. There are many pre-clinical studies on MSC treatment for spinal cord injury (SCI) and peripheral nerve injuries. However, the same is not true for clinical trials, particularly those concerned with nerve trauma, indicating the necessity of more well-constructed studies showing the benefits that cell therapy can provide for individuals suffering the consequences of nerve lesions. As for clinical trials for SCI treatment the results obtained so far are not as beneficial as those described in experimental studies. For these reasons basic and pre-clinical studies dealing with MSC therapy should emphasize the standardization of protocols that could be translated to the clinical set with consistent and positive outcomes. This review is based on pre-clinical studies and clinical trials available in the literature from 2010 until now. At the time of writing this article there were 43 and 36 pre-clinical and 19 and 1 clinical trials on injured spinal cord and peripheral nerves, respectively.
Collapse
Affiliation(s)
- Ana Maria Blanco Martinez
- Ana Maria Blanco Martinez, Camila de Oliveira Goulart, Bruna dos Santos Ramalho, Júlia Teixeira Oliveira, Fernanda Martins Almeida, Laboratory of Neurodegeneration and Repair, Institute of Biomedical Sciences, Health Science Center, 21941-902, Rio de Janeiro, Brazil
| | - Camila de Oliveira Goulart
- Ana Maria Blanco Martinez, Camila de Oliveira Goulart, Bruna dos Santos Ramalho, Júlia Teixeira Oliveira, Fernanda Martins Almeida, Laboratory of Neurodegeneration and Repair, Institute of Biomedical Sciences, Health Science Center, 21941-902, Rio de Janeiro, Brazil
| | - Bruna Dos Santos Ramalho
- Ana Maria Blanco Martinez, Camila de Oliveira Goulart, Bruna dos Santos Ramalho, Júlia Teixeira Oliveira, Fernanda Martins Almeida, Laboratory of Neurodegeneration and Repair, Institute of Biomedical Sciences, Health Science Center, 21941-902, Rio de Janeiro, Brazil
| | - Júlia Teixeira Oliveira
- Ana Maria Blanco Martinez, Camila de Oliveira Goulart, Bruna dos Santos Ramalho, Júlia Teixeira Oliveira, Fernanda Martins Almeida, Laboratory of Neurodegeneration and Repair, Institute of Biomedical Sciences, Health Science Center, 21941-902, Rio de Janeiro, Brazil
| | - Fernanda Martins Almeida
- Ana Maria Blanco Martinez, Camila de Oliveira Goulart, Bruna dos Santos Ramalho, Júlia Teixeira Oliveira, Fernanda Martins Almeida, Laboratory of Neurodegeneration and Repair, Institute of Biomedical Sciences, Health Science Center, 21941-902, Rio de Janeiro, Brazil
| |
Collapse
|
17
|
Cantinieaux D, Quertainmont R, Blacher S, Rossi L, Wanet T, Noël A, Brook G, Schoenen J, Franzen R. Conditioned medium from bone marrow-derived mesenchymal stem cells improves recovery after spinal cord injury in rats: an original strategy to avoid cell transplantation. PLoS One 2013; 8:e69515. [PMID: 24013448 PMCID: PMC3754952 DOI: 10.1371/journal.pone.0069515] [Citation(s) in RCA: 171] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2013] [Accepted: 06/10/2013] [Indexed: 12/11/2022] Open
Abstract
Spinal cord injury triggers irreversible loss of motor and sensory functions. Numerous strategies aiming at repairing the injured spinal cord have been studied. Among them, the use of bone marrow-derived mesenchymal stem cells (BMSCs) is promising. Indeed, these cells possess interesting properties to modulate CNS environment and allow axon regeneration and functional recovery. Unfortunately, BMSC survival and differentiation within the host spinal cord remain poor, and these cells have been found to have various adverse effects when grafted in other pathological contexts. Moreover, paracrine-mediated actions have been proposed to explain the beneficial effects of BMSC transplantation after spinal cord injury. We thus decided to deliver BMSC-released factors to spinal cord injured rats and to study, in parallel, their properties in vitro. We show that, in vitro, BMSC-conditioned medium (BMSC-CM) protects neurons from apoptosis, activates macrophages and is pro-angiogenic. In vivo, BMSC-CM administered after spinal cord contusion improves motor recovery. Histological analysis confirms the pro-angiogenic action of BMSC-CM, as well as a tissue protection effect. Finally, the characterization of BMSC-CM by cytokine array and ELISA identified trophic factors as well as cytokines likely involved in the beneficial observed effects. In conclusion, our results support the paracrine-mediated mode of action of BMSCs and raise the possibility to develop a cell-free therapeutic approach.
Collapse
Affiliation(s)
- Dorothée Cantinieaux
- GIGA-Neuroscience, Axonal Regeneration and Cephalic Pain Unit, University of Liege, Liege, Belgium
| | - Renaud Quertainmont
- GIGA-Neuroscience, Axonal Regeneration and Cephalic Pain Unit, University of Liege, Liege, Belgium
| | - Silvia Blacher
- GIGA-Cancer, Laboratory of Biology of Tumour and Development, University of Liege, Liege, Belgium
| | - Loïc Rossi
- GIGA-Neuroscience, Axonal Regeneration and Cephalic Pain Unit, University of Liege, Liege, Belgium
| | - Thomas Wanet
- GIGA-Neuroscience, Axonal Regeneration and Cephalic Pain Unit, University of Liege, Liege, Belgium
| | - Agnès Noël
- GIGA-Cancer, Laboratory of Biology of Tumour and Development, University of Liege, Liege, Belgium
| | - Gary Brook
- Department of Neuropathology, University of Aachen, Aachen, Germany
| | - Jean Schoenen
- GIGA-Neuroscience, Axonal Regeneration and Cephalic Pain Unit, University of Liege, Liege, Belgium
| | - Rachelle Franzen
- GIGA-Neuroscience, Axonal Regeneration and Cephalic Pain Unit, University of Liege, Liege, Belgium
| |
Collapse
|
18
|
Li J, Lepski G. Cell transplantation for spinal cord injury: a systematic review. BIOMED RESEARCH INTERNATIONAL 2013; 2013:786475. [PMID: 23484157 PMCID: PMC3581246 DOI: 10.1155/2013/786475] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 09/10/2012] [Revised: 11/16/2012] [Accepted: 12/11/2012] [Indexed: 02/07/2023]
Abstract
Cell transplantation, as a therapeutic intervention for spinal cord injury (SCI), has been extensively studied by researchers in recent years. A number of different kinds of stem cells, neural progenitors, and glial cells have been tested in basic research, and most have been excluded from clinical studies because of a variety of reasons, including safety and efficacy. The signaling pathways, protein interactions, cellular behavior, and the differentiated fates of experimental cells have been studied in vitro in detail. Furthermore, the survival, proliferation, differentiation, and effects on promoting functional recovery of transplanted cells have also been examined in different animal SCI models. However, despite significant progress, a "bench to bedside" gap still exists. In this paper, we comprehensively cover publications in the field from the last years. The most commonly utilized cell lineages were covered in this paper and specific areas covered include survival of grafted cells, axonal regeneration and remyelination, sensory and motor functional recovery, and electrophysiological improvements. Finally we also review the literature on the in vivo tracking techniques for transplanted cells.
Collapse
Affiliation(s)
- Jun Li
- Department of Neurosurgery, Eberhard Karls University, 72076 Tübingen, Germany
- Department of Spine Surgery, The Affiliated Hospital of Luzhou Medical College, 646000 Luzhou, China
| | - Guilherme Lepski
- Department of Neurosurgery, Eberhard Karls University, 72076 Tübingen, Germany
- Division of Neurosurgery, Department of Neurology, Faculdade de Medicina, Universidade de São Paulo, Avnida Dr. Enéas de Carvalho Aguiar 255, 05403-000 São Paulo, SP, Brazil
| |
Collapse
|