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Semmler L, Naghilou A, Millesi F, Wolf S, Mann A, Stadlmayr S, Mero S, Ploszczanski L, Greutter L, Woehrer A, Placheta-Györi E, Vollrath F, Weiss T, Radtke C. Silk-in-Silk Nerve Guidance Conduits Enhance Regeneration in a Rat Sciatic Nerve Injury Model. Adv Healthc Mater 2023; 12:e2203237. [PMID: 36683305 DOI: 10.1002/adhm.202203237] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Indexed: 01/24/2023]
Abstract
Advanced nerve guidance conduits can provide an off-the-shelf alternative to autografts for the rehabilitation of segmental peripheral nerve injuries. In this study, the excellent processing ability of silk fibroin and the outstanding cell adhesion quality of spider dragline silk are combined to generate a silk-in-silk conduit for nerve repair. Fibroin-based silk conduits (SC) are characterized, and Schwann cells are seeded on the conduits and spider silk. Rat sciatic nerve (10 mm) defects are treated with an autograft (A), an empty SC, or a SC filled with longitudinally aligned spider silk fibers (SSC) for 14 weeks. Functional recovery, axonal re-growth, and re-myelination are assessed. The material characterizations determine a porous nature of the conduit. Schwann cells accept the conduit and spider silk as growth substrate. The in vivo results show a significantly faster functional regeneration of the A and SSC group compared to the SC group. In line with the functional results, the histomorphometrical analysis determines a comparable axon density of the A and SSC groups, which is significantly higher than the SC group. These findings demonstrate that the here introduced silk-in-silk nerve conduit achieves a similar regenerative performance as autografts largely due to the favorable guiding properties of spider dragline silk.
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Affiliation(s)
- Lorenz Semmler
- Department of Plastic, Reconstructive, and Aesthetic Surgery, Medical University of Vienna, Spitalgasse 23, Vienna, 1090, Austria.,Austrian Cluster for Tissue Regeneration, Vienna, 1200, Austria
| | - Aida Naghilou
- Department of Plastic, Reconstructive, and Aesthetic Surgery, Medical University of Vienna, Spitalgasse 23, Vienna, 1090, Austria
| | - Flavia Millesi
- Department of Plastic, Reconstructive, and Aesthetic Surgery, Medical University of Vienna, Spitalgasse 23, Vienna, 1090, Austria.,Austrian Cluster for Tissue Regeneration, Vienna, 1200, Austria
| | - Sonja Wolf
- Department of Plastic, Reconstructive, and Aesthetic Surgery, Medical University of Vienna, Spitalgasse 23, Vienna, 1090, Austria
| | - Anda Mann
- Department of Plastic, Reconstructive, and Aesthetic Surgery, Medical University of Vienna, Spitalgasse 23, Vienna, 1090, Austria
| | - Sarah Stadlmayr
- Department of Plastic, Reconstructive, and Aesthetic Surgery, Medical University of Vienna, Spitalgasse 23, Vienna, 1090, Austria
| | - Sascha Mero
- Department of Plastic, Reconstructive, and Aesthetic Surgery, Medical University of Vienna, Spitalgasse 23, Vienna, 1090, Austria
| | - Leon Ploszczanski
- Institute of Physics and Materials Science, University of Natural Resources and Life Sciences, Gregor-Medel-Straße 33, Vienna, 1180, Austria
| | - Lisa Greutter
- Department of Neurology, Division of Neuropathology and Neurochemistry, Medical University of Vienna, Spitalgasse 23, Vienna, 1090, Austria
| | - Adelheid Woehrer
- Department of Neurology, Division of Neuropathology and Neurochemistry, Medical University of Vienna, Spitalgasse 23, Vienna, 1090, Austria
| | - Eva Placheta-Györi
- Department of Plastic, Reconstructive, and Aesthetic Surgery, Medical University of Vienna, Spitalgasse 23, Vienna, 1090, Austria
| | - Fritz Vollrath
- Department of Zoology, University of Oxford, Mansfield Rd., Oxford, OX1 3SZ, UK
| | - Tamara Weiss
- Department of Plastic, Reconstructive, and Aesthetic Surgery, Medical University of Vienna, Spitalgasse 23, Vienna, 1090, Austria.,Austrian Cluster for Tissue Regeneration, Vienna, 1200, Austria
| | - Christine Radtke
- Department of Plastic, Reconstructive, and Aesthetic Surgery, Medical University of Vienna, Spitalgasse 23, Vienna, 1090, Austria.,Austrian Cluster for Tissue Regeneration, Vienna, 1200, Austria
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Li Y, Fraser D, Mereness J, Van Hove A, Basu S, Newman M, Benoit DSW. Tissue Engineered Neurovascularization Strategies for Craniofacial Tissue Regeneration. ACS APPLIED BIO MATERIALS 2022; 5:20-39. [PMID: 35014834 PMCID: PMC9016342 DOI: 10.1021/acsabm.1c00979] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Craniofacial tissue injuries, diseases, and defects, including those within bone, dental, and periodontal tissues and salivary glands, impact an estimated 1 billion patients globally. Craniofacial tissue dysfunction significantly reduces quality of life, and successful repair of damaged tissues remains a significant challenge. Blood vessels and nerves are colocalized within craniofacial tissues and act synergistically during tissue regeneration. Therefore, the success of craniofacial regenerative approaches is predicated on successful recruitment, regeneration, or integration of both vascularization and innervation. Tissue engineering strategies have been widely used to encourage vascularization and, more recently, to improve innervation through host tissue recruitment or prevascularization/innervation of engineered tissues. However, current scaffold designs and cell or growth factor delivery approaches often fail to synergistically coordinate both vascularization and innervation to orchestrate successful tissue regeneration. Additionally, tissue engineering approaches are typically investigated separately for vascularization and innervation. Since both tissues act in concert to improve craniofacial tissue regeneration outcomes, a revised approach for development of engineered materials is required. This review aims to provide an overview of neurovascularization in craniofacial tissues and strategies to target either process thus far. Finally, key design principles are described for engineering approaches that will support both vascularization and innervation for successful craniofacial tissue regeneration.
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Affiliation(s)
- Yiming Li
- Department of Biomedical Engineering, University of Rochester, Rochester, New York 14627, United States.,Department of Orthopaedics and Center for Musculoskeletal Research, University of Rochester Medical Center, Rochester, New York 14642, United States
| | - David Fraser
- Department of Orthopaedics and Center for Musculoskeletal Research, University of Rochester Medical Center, Rochester, New York 14642, United States.,Eastman Institute for Oral Health, University of Rochester Medical Center, Rochester, New York 14620, United States.,Translational Biomedical Sciences Program, University of Rochester Medical Center, Rochester, New York 14642, United States
| | - Jared Mereness
- Department of Biomedical Engineering, University of Rochester, Rochester, New York 14627, United States.,Department of Orthopaedics and Center for Musculoskeletal Research, University of Rochester Medical Center, Rochester, New York 14642, United States.,Department of Environmental Medicine, University of Rochester Medical Center, Rochester, New York 14642, United States
| | - Amy Van Hove
- Department of Biomedical Engineering, University of Rochester, Rochester, New York 14627, United States.,Department of Orthopaedics and Center for Musculoskeletal Research, University of Rochester Medical Center, Rochester, New York 14642, United States
| | - Sayantani Basu
- Department of Biomedical Engineering, University of Rochester, Rochester, New York 14627, United States.,Department of Orthopaedics and Center for Musculoskeletal Research, University of Rochester Medical Center, Rochester, New York 14642, United States
| | - Maureen Newman
- Department of Biomedical Engineering, University of Rochester, Rochester, New York 14627, United States.,Department of Orthopaedics and Center for Musculoskeletal Research, University of Rochester Medical Center, Rochester, New York 14642, United States
| | - Danielle S W Benoit
- Department of Biomedical Engineering, University of Rochester, Rochester, New York 14627, United States.,Department of Orthopaedics and Center for Musculoskeletal Research, University of Rochester Medical Center, Rochester, New York 14642, United States.,Eastman Institute for Oral Health, University of Rochester Medical Center, Rochester, New York 14620, United States.,Translational Biomedical Sciences Program, University of Rochester Medical Center, Rochester, New York 14642, United States.,Department of Environmental Medicine, University of Rochester Medical Center, Rochester, New York 14642, United States.,Materials Science Program, University of Rochester, Rochester, New York 14627, United States.,Department of Chemical Engineering, University of Rochester, Rochester, New York 14627, United States.,Department of Biomedical Genetics and Center for Oral Biology, University of Rochester Medical Center, Rochester, New York 14642, United States
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Millesi F, Weiss T, Mann A, Haertinger M, Semmler L, Supper P, Pils D, Naghilou A, Radtke C. Defining the regenerative effects of native spider silk fibers on primary Schwann cells, sensory neurons, and nerve-associated fibroblasts. FASEB J 2021; 35:e21196. [PMID: 33210360 PMCID: PMC7894153 DOI: 10.1096/fj.202001447r] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Revised: 09/25/2020] [Accepted: 10/30/2020] [Indexed: 01/09/2023]
Abstract
The search for a suitable material to promote regeneration after long-distance peripheral nerve defects turned the spotlight on spider silk. Nerve conduits enriched with native spider silk fibers as internal guiding structures previously demonstrated a regenerative outcome similar to autologous nerve grafts in animal studies. Nevertheless, spider silk is a natural material with associated limitations for clinical use. A promising alternative is the production of recombinant silk fibers that should mimic the outstanding properties of their native counterpart. However, in vitro data on the regenerative features that native silk fibers provide for cells involved in nerve regeneration are scarce. Thus, there is a lack of reference parameters to evaluate whether recombinant silk fiber candidates will be eligible for nerve repair in vivo. To gain insight into the regenerative effect of native spider silk, our study aims to define the behavioral response of primary Schwann cells (SCs), nerve-associated fibroblasts (FBs), and dorsal root ganglion (DRG) neurons cultured on native dragline silk from the genus Nephila and on laminin coated dishes. The established multi-color immunostaining panels together with confocal microscopy and live cell imaging enabled the analysis of cell identity, morphology, proliferation, and migration on both substrates in detail. Our findings demonstrated that native spider silk rivals laminin coating as it allowed attachment and proliferation and supported the characteristic behavior of all tested cell types. Axonal out-growth of DRG neurons occurred along longitudinally aligned SCs that formed sustained bundled structures resembling Bungner bands present in regenerating nerves. The migration of SCs along the silk fibers achieved the reported distance of regenerating axons of about 1 mm per day, but lacked directionality. Furthermore, rFBs significantly reduced the velocity of rSCs in co-cultures on silk fibers. In summary, this study (a) reveals features recombinant silk must possess and what modifications or combinations could be useful for enhanced nerve repair and (b) provides assays to evaluate the regenerative performance of silk fibers in vitro before being applied as internal guiding structure in nerve conduits in vivo.
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Affiliation(s)
- Flavia Millesi
- Research Laboratory of the Division of Plastic and Reconstructive SurgeryDepartment of SurgeryMedical University of ViennaViennaAustria
- Austrian Cluster for Tissue RegenerationViennaAustria
| | - Tamara Weiss
- Research Laboratory of the Division of Plastic and Reconstructive SurgeryDepartment of SurgeryMedical University of ViennaViennaAustria
- Austrian Cluster for Tissue RegenerationViennaAustria
| | - Anda Mann
- Research Laboratory of the Division of Plastic and Reconstructive SurgeryDepartment of SurgeryMedical University of ViennaViennaAustria
| | - Maximilian Haertinger
- Research Laboratory of the Division of Plastic and Reconstructive SurgeryDepartment of SurgeryMedical University of ViennaViennaAustria
- Austrian Cluster for Tissue RegenerationViennaAustria
| | - Lorenz Semmler
- Research Laboratory of the Division of Plastic and Reconstructive SurgeryDepartment of SurgeryMedical University of ViennaViennaAustria
| | - Paul Supper
- Research Laboratory of the Division of Plastic and Reconstructive SurgeryDepartment of SurgeryMedical University of ViennaViennaAustria
| | - Dietmar Pils
- Division of General SurgeryDepartment of SurgeryComprehensive Cancer Center ViennaMedical University of ViennaViennaAustria
| | - Aida Naghilou
- Research Laboratory of the Division of Plastic and Reconstructive SurgeryDepartment of SurgeryMedical University of ViennaViennaAustria
| | - Christine Radtke
- Research Laboratory of the Division of Plastic and Reconstructive SurgeryDepartment of SurgeryMedical University of ViennaViennaAustria
- Austrian Cluster for Tissue RegenerationViennaAustria
- Division of Plastic and Reconstructive SurgeryDepartment of SurgeryMedical University of ViennaViennaAustria
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Carvalho CR, Chang W, Silva‐Correia J, Reis RL, Oliveira JM, Kohn J. Engineering Silk Fibroin-Based Nerve Conduit with Neurotrophic Factors for Proximal Protection after Peripheral Nerve Injury. Adv Healthc Mater 2021; 10:e2000753. [PMID: 33169544 DOI: 10.1002/adhm.202000753] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 10/15/2020] [Indexed: 12/11/2022]
Abstract
Artificial nerve conduits capable of adequately releasing neurotrophic factors are extensively studied to bridge nerve defects. However, the lack of neurotrophic factors in the proximal area and their visible effects in axonal retrograde transport following nerve injury is one of the factors causing an incomplete nerve regeneration. Herein, an advanced conduit made of silk fibroin is produced, which can incorporate growth factors and promote an effective regeneration after injury. For that, enzymatically crosslinked silk fibroin-based conduits are developed to be used as a platform for the controlled delivery of neurotrophic factors. Nerve growth factor and glial-cell line derived neurotrophic factor (GDNF) are incorporated using two different methodologies: i) crosslinking and ii) absorption method. The release profile is measured by ELISA technique. The bioactivity of the neurotrophic factors is evaluated in vitro by using primary dorsal root ganglia. When implanted in a 10 mm sciatic nerve defect in rats, GDNF-loaded silk fibroin conduits reveal retrograde neuroprotection as compared to autografts and plain silk fibroin conduit. Therefore, the novel design presents a substantial improvement of retrograde trafficking, neurons' protection, and motor nerve reinnervation.
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Affiliation(s)
- Cristiana R. Carvalho
- 3B's Research Group‐Biomaterials Biodegradables and Biomimetics Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine University of Minho Barco Guimarães 4805‐017 Portugal
| | - Wei Chang
- New Jersey Center for Biomaterials Rutgers The State University of New Jersey Piscataway NJ 08854 USA
| | - Joana Silva‐Correia
- 3B's Research Group‐Biomaterials Biodegradables and Biomimetics Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine University of Minho Barco Guimarães 4805‐017 Portugal
| | - Rui L. Reis
- 3B's Research Group‐Biomaterials Biodegradables and Biomimetics Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine University of Minho Barco Guimarães 4805‐017 Portugal
| | - Joaquim M. Oliveira
- 3B's Research Group‐Biomaterials Biodegradables and Biomimetics Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine University of Minho Barco Guimarães 4805‐017 Portugal
| | - Joachim Kohn
- New Jersey Center for Biomaterials Rutgers The State University of New Jersey Piscataway NJ 08854 USA
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Ngo TB, Spearman BS, Hlavac N, Schmidt CE. Three-Dimensional Bioprinted Hyaluronic Acid Hydrogel Test Beds for Assessing Neural Cell Responses to Competitive Growth Stimuli. ACS Biomater Sci Eng 2020; 6:6819-6830. [DOI: 10.1021/acsbiomaterials.0c00940] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Tran B. Ngo
- J. Crayton Pruitt Department of Biomedical Engineering, University of Florida, Gainesville, Florida 32611, United States
| | - Benjamin S. Spearman
- J. Crayton Pruitt Department of Biomedical Engineering, University of Florida, Gainesville, Florida 32611, United States
| | - Nora Hlavac
- J. Crayton Pruitt Department of Biomedical Engineering, University of Florida, Gainesville, Florida 32611, United States
| | - Christine E. Schmidt
- J. Crayton Pruitt Department of Biomedical Engineering, University of Florida, Gainesville, Florida 32611, United States
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Fadia NB, Bliley JM, DiBernardo GA, Crammond DJ, Schilling BK, Sivak WN, Spiess AM, Washington KM, Waldner M, Liao HT, James IB, Minteer DM, Tompkins-Rhoades C, Cottrill AR, Kim DY, Schweizer R, Bourne DA, Panagis GE, Asher Schusterman M, Egro FM, Campwala IK, Simpson T, Weber DJ, Gause T, Brooker JE, Josyula T, Guevara AA, Repko AJ, Mahoney CM, Marra KG. Long-gap peripheral nerve repair through sustained release of a neurotrophic factor in nonhuman primates. Sci Transl Med 2020; 12:12/527/eaav7753. [DOI: 10.1126/scitranslmed.aav7753] [Citation(s) in RCA: 58] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2019] [Revised: 08/26/2019] [Accepted: 11/25/2019] [Indexed: 01/09/2023]
Abstract
Severe injuries to peripheral nerves are challenging to repair. Standard-of-care treatment for nerve gaps >2 to 3 centimeters is autografting; however, autografting can result in neuroma formation, loss of sensory function at the donor site, and increased operative time. To address the need for a synthetic nerve conduit to treat large nerve gaps, we investigated a biodegradable poly(caprolactone) (PCL) conduit with embedded double-walled polymeric microspheres encapsulating glial cell line–derived neurotrophic factor (GDNF) capable of providing a sustained release of GDNF for >50 days in a 5-centimeter nerve defect in a rhesus macaque model. The GDNF-eluting conduit (PCL/GDNF) was compared to a median nerve autograft and a PCL conduit containing empty microspheres (PCL/Empty). Functional testing demonstrated similar functional recovery between the PCL/GDNF-treated group (75.64 ± 10.28%) and the autograft-treated group (77.49 ± 19.28%); both groups were statistically improved compared to PCL/Empty-treated group (44.95 ± 26.94%). Nerve conduction velocity 1 year after surgery was increased in the PCL/GDNF-treated macaques (31.41 ± 15.34 meters/second) compared to autograft (25.45 ± 3.96 meters/second) and PCL/Empty (12.60 ± 3.89 meters/second) treatment. Histological analyses included assessment of Schwann cell presence, myelination of axons, nerve fiber density, and g-ratio. PCL/GDNF group exhibited a statistically greater average area occupied by individual Schwann cells at the distal nerve (11.60 ± 33.01 μm2) compared to autograft (4.62 ± 3.99 μm2) and PCL/Empty (4.52 ± 5.16 μm2) treatment groups. This study demonstrates the efficacious bridging of a long peripheral nerve gap in a nonhuman primate model using an acellular, biodegradable nerve conduit.
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Affiliation(s)
- Neil B. Fadia
- Department of Plastic Surgery, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Jacqueline M. Bliley
- Department of Plastic Surgery, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | | | - Donald J. Crammond
- Department of Neurosurgery, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | | | - Wesley N. Sivak
- Department of Plastic Surgery, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Alexander M. Spiess
- Department of Plastic Surgery, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Kia M. Washington
- Department of Plastic Surgery, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Matthias Waldner
- Department of Plastic Surgery, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Han-Tsung Liao
- Department of Plastic Surgery, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Isaac B. James
- Department of Plastic Surgery, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Danielle M. Minteer
- Department of Plastic Surgery, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | | | - Adam R. Cottrill
- Department of Neuroscience, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Deok-Yeol Kim
- Department of Plastic Surgery, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Riccardo Schweizer
- Department of Plastic Surgery, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Debra A. Bourne
- Department of Plastic Surgery, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - George E. Panagis
- Department of Biology, University of Pittsburgh, Greensburg, PA 15601, USA
| | - M. Asher Schusterman
- Department of Plastic Surgery, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Francesco M. Egro
- Department of Plastic Surgery, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | | | - Tyler Simpson
- Department of Physical Medicine and Rehabilitation, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Douglas J. Weber
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA 15213, USA
- Department of Physical Medicine and Rehabilitation, University of Pittsburgh, Pittsburgh, PA 15213, USA
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA 15219, USA
| | - Trent Gause
- Department of Plastic Surgery, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Jack E. Brooker
- Department of Plastic Surgery, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Tvisha Josyula
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Astrid A. Guevara
- Department of Plastic Surgery, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Alexander J. Repko
- Department of Plastic Surgery, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | | | - Kacey G. Marra
- Department of Plastic Surgery, University of Pittsburgh, Pittsburgh, PA 15213, USA
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA 15213, USA
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA 15219, USA
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7
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Carvalho CR, Oliveira JM, Reis RL. Modern Trends for Peripheral Nerve Repair and Regeneration: Beyond the Hollow Nerve Guidance Conduit. Front Bioeng Biotechnol 2019; 7:337. [PMID: 31824934 PMCID: PMC6882937 DOI: 10.3389/fbioe.2019.00337] [Citation(s) in RCA: 153] [Impact Index Per Article: 30.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Accepted: 10/30/2019] [Indexed: 12/13/2022] Open
Abstract
Peripheral nerve repair and regeneration remains among the greatest challenges in tissue engineering and regenerative medicine. Even though peripheral nerve injuries (PNIs) are capable of some degree of regeneration, frail recovery is seen even when the best microsurgical technique is applied. PNIs are known to be very incapacitating for the patient, due to the deprivation of motor and sensory abilities. Since there is no optimal solution for tackling this problem up to this day, the evolution in the field is constant, with innovative designs of advanced nerve guidance conduits (NGCs) being reported every day. As a basic concept, a NGC should act as a physical barrier from the external environment, concomitantly acting as physical guidance for the regenerative axons across the gap lesion. NGCs should also be able to retain the naturally released nerve growth factors secreted by the damaged nerve stumps, as well as reducing the invasion of scar tissue-forming fibroblasts to the injury site. Based on the neurobiological knowledge related to the events that succeed after a nerve injury, neuronal subsistence is subjected to the existence of an ideal environment of growth factors, hormones, cytokines, and extracellular matrix (ECM) factors. Therefore, it is known that multifunctional NGCs fabricated through combinatorial approaches are needed to improve the functional and clinical outcomes after PNIs. The present work overviews the current reports dealing with the several features that can be used to improve peripheral nerve regeneration (PNR), ranging from the simple use of hollow NGCs to tissue engineered intraluminal fillers, or to even more advanced strategies, comprising the molecular and gene therapies as well as cell-based therapies.
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Affiliation(s)
- Cristiana R. Carvalho
- 3B's Research Group, I3Bs – Research Institute on Biomaterials, Biodegradables and Biomimetics, University of Minho, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine, Guimarães, Portugal
- ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal
- The Discoveries Centre for Regenerative and Precision Medicine, Headquarters at University of Minho, Avepark, Guimarães, Portugal
| | - Joaquim M. Oliveira
- 3B's Research Group, I3Bs – Research Institute on Biomaterials, Biodegradables and Biomimetics, University of Minho, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine, Guimarães, Portugal
- ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal
- The Discoveries Centre for Regenerative and Precision Medicine, Headquarters at University of Minho, Avepark, Guimarães, Portugal
| | - Rui L. Reis
- 3B's Research Group, I3Bs – Research Institute on Biomaterials, Biodegradables and Biomimetics, University of Minho, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine, Guimarães, Portugal
- ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal
- The Discoveries Centre for Regenerative and Precision Medicine, Headquarters at University of Minho, Avepark, Guimarães, Portugal
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8
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Controlling the dose-dependent, synergistic and temporal effects of NGF and GDNF by encapsulation in PLGA microparticles for use in nerve guidance conduits for the repair of large peripheral nerve defects. J Control Release 2019; 304:51-64. [DOI: 10.1016/j.jconrel.2019.05.001] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Revised: 04/18/2019] [Accepted: 05/01/2019] [Indexed: 12/13/2022]
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9
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Passipieri JA, Dienes J, Frank J, Glazier J, Portell A, Venkatesh KP, Bliley JM, Grybowski D, Schilling BK, Marra KG, Christ GJ. Adipose Stem Cells Enhance Nerve Regeneration and Muscle Function in a Peroneal Nerve Ablation Model. Tissue Eng Part A 2019; 27:297-310. [PMID: 30760135 DOI: 10.1089/ten.tea.2018.0244] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Severe peripheral nerve injuries have devastating consequences on the quality of life in affected patients, and they represent a significant unmet medical need. Destruction of nerve fibers results in denervation of targeted muscles, which, subsequently, undergo progressive atrophy and loss of function. Timely restoration of neural innervation to muscle fibers is crucial to the preservation of muscle homeostasis and function. The goal of this study was to evaluate the impact of addition of adipose stem cells (ASCs) to polycaprolactone (PCL) nerve conduit guides on peripheral nerve repair and functional muscle recovery in the setting of a critical size nerve defect. To this end, peripheral nerve injury was created by surgically ablating 6 mm of the common peroneal nerve in a rat model. A PCL nerve guide, filled with ASCs and/or poloxamer hydrogel, was sutured to the nerve ends. Negative and positive controls included nerve ablation only (no repair), and reversed polarity autograft nerve implant, respectively. Tibialis anterior (TA) muscle function was assessed at 4, 8, and 12 weeks postinjury, and nerve and muscle tissue was retrieved at the 12-week terminal time point. Inclusion of ASCs in the PCL nerve guide elicited statistically significant time-dependent increases in functional recovery (contraction) after denervation; ∼25% higher than observed in acellular (poloxamer-filled) implants and indistinguishable from autograft implants, respectively, at 12 weeks postinjury (p < 0.05, n = 7-8 in each group). Analysis of single muscle fiber cross-sectional area (CSA) revealed that ASC-based treatment of nerve injury provided a better recapitulation of the overall distribution of muscle fiber CSAs observed in the contralateral TA muscle of uninjured limbs. In addition, the presence of ASCs was associated with improved features of re-innervation distal to the defect, with respect to neurofilament and S100 (Schwann cell marker) expression. In conclusion, these initial studies indicate significant benefits of inclusion of ASCs to the rate and magnitude of both peripheral nerve regeneration and functional recovery of muscle contraction, to levels equivalent to autograft implantation. These findings have important implications to improved nerve repair, and they provide input for future work directed to restoration of nerve and muscle function after polytraumatic injury. Impact Statement This works explores the application of adipose stem cells (ASCs) for peripheral nerve regeneration in a rat model. Herein, we demonstrate that the addition of ASCs in poloxamer-filled PCL nerve guide conduits impacts nerve regeneration and recovery of muscle function, to levels equivalent to autograft implantation, which is considered to be the current gold standard treatment. This study builds on the importance of a timely restoration of innervation to muscle fibers for preservation of muscle homeostasis, and it will provide input for future work aiming at restoring nerve and muscle function after polytraumatic injury.
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Affiliation(s)
- Juliana A Passipieri
- Biomedical Engineering Department, University of Virginia, Charlottesville, Virginia
| | - Jack Dienes
- Biomedical Engineering Department, University of Virginia, Charlottesville, Virginia
| | - Joseph Frank
- Biomedical Engineering Department, University of Virginia, Charlottesville, Virginia
| | - Joshua Glazier
- Biomedical Engineering Department, University of Virginia, Charlottesville, Virginia
| | - Andrew Portell
- Biomedical Engineering Department, University of Virginia, Charlottesville, Virginia
| | - Kaushik P Venkatesh
- Department of Bioengineering and University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Jacqueline M Bliley
- Department of Plastic Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Damian Grybowski
- Department of Plastic Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Benjamin K Schilling
- Department of Bioengineering and University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Kacey G Marra
- Department of Bioengineering and University of Pittsburgh, Pittsburgh, Pennsylvania.,Department of Plastic Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania.,McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - George J Christ
- Biomedical Engineering Department, University of Virginia, Charlottesville, Virginia.,Orthopaedics Department, University of Virginia, Charlottesville, Virginia
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10
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Sun AX, Prest TA, Fowler JR, Brick RM, Gloss KM, Li X, DeHart M, Shen H, Yang G, Brown BN, Alexander PG, Tuan RS. Conduits harnessing spatially controlled cell-secreted neurotrophic factors improve peripheral nerve regeneration. Biomaterials 2019; 203:86-95. [DOI: 10.1016/j.biomaterials.2019.01.038] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Revised: 12/15/2018] [Accepted: 01/24/2019] [Indexed: 02/07/2023]
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11
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Lee Y, Kong C, Chang JW, Jun SB. Carbon-Fiber Based Microelectrode Array Embedded with a Biodegradable Silk Support for In Vivo Neural Recording. J Korean Med Sci 2019; 34:e24. [PMID: 30686948 PMCID: PMC6345632 DOI: 10.3346/jkms.2019.34.e24] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Accepted: 12/13/2018] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Recently, carbon fibers have been utilized to develop a depth-type microelectrode array for chronic neural recording. Since the diameter of carbon fibers is smaller than the conventional electrodes made of metal wires or microfabricated silicon, the carbon fiber electrodes showed an improved capability for chronic neural recording with less tissue damages. However, the carbon fiber based microelectrodes have a limitation of short insertion depth due to a low stiffness. METHODS We proposed a carbon fiber based microelectrode array embedded with a mechanical support structure to facilitate the penetration into the deeper brain. The support is made of biodegradable silk fibroin to reduce the reactive tissue responses. The 4-channel carbon fiber based microelectrode arrays were fabricated and accessed in terms of electrochemical impedance, recording capability for 1-month implantation in rat hippocampi. The electrodes with tungsten supports were fabricated and tested as a control group. Immunohistochemical analysis was performed to identify the reactive glial responses. RESULTS The carbon fiber based electrode arrays with silk supports showed about 2-fold impedance increase 2 weeks after implantation while the number of active electrodes decreased simultaneously. However, after 1 month, the electrode impedance decreased back to its initial value and the percentage of active electrodes also increased above 70%. Immunohistochemical staining clearly showed that the electrodes with silk supports induced less reactive glial responses than that with tungsten supports. CONCLUSION The proposed carbon fiber based microelectrode array is expected to be used for long-term in vivo neural recording from deep brain regions with the minimized reactive tissue response.
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Affiliation(s)
- Yena Lee
- Department of Electronic and Electrical Engineering, ELTEC College of Engineering, Ewha Womans University, Seoul, Korea
| | - Chanho Kong
- Department of Neurosurgery, Yonsei University College of Medicine, Seoul, Korea
| | - Jin Woo Chang
- Department of Neurosurgery, Yonsei University College of Medicine, Seoul, Korea
| | - Sang Beom Jun
- Department of Electronic and Electrical Engineering, ELTEC College of Engineering, Ewha Womans University, Seoul, Korea
- Department of Brain and Cognitive Science, College of Scranton, Ewha Womans University, Seoul, Korea
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12
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Magaz A, Faroni A, Gough JE, Reid AJ, Li X, Blaker JJ. Bioactive Silk-Based Nerve Guidance Conduits for Augmenting Peripheral Nerve Repair. Adv Healthc Mater 2018; 7:e1800308. [PMID: 30260575 DOI: 10.1002/adhm.201800308] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2018] [Revised: 05/22/2018] [Indexed: 02/03/2023]
Abstract
Repair of peripheral nerve injuries depends upon complex biology stemming from the manifold and challenging injury-healing processes of the peripheral nervous system. While surgical treatment options are available, they tend to be characterized by poor clinical outcomes for the injured patients. This is particularly apparent in the clinical management of a nerve gap whereby nerve autograft remains the best clinical option despite numerous limitations; in addition, effective repair becomes progressively more difficult with larger gaps. Nerve conduit strategies based on tissue engineering approaches and the use of silk as scaffolding material have attracted much attention in recent years to overcome these limitations and meet the clinical demand of large gap nerve repair. This review examines the scientific advances made with silk-based conduits for peripheral nerve repair. The focus is on enhancing bioactivity of the conduits in terms of physical guidance cues, inner wall and lumen modification, and imbuing novel conductive functionalities.
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Affiliation(s)
- Adrián Magaz
- Bio‐Active Materials GroupSchool of MaterialsMSS TowerThe University of Manchester Manchester M13 9PL UK
- Institute of Materials Research and Engineering (IMRE)Agency for Science Technology and Research (A*STAR) 2 Fusionopolis, Way, Innovis #08‐03 Singapore 138634 Singapore
| | - Alessandro Faroni
- Blond McIndoe LaboratoriesDivision of Cell Matrix Biology and Regenerative MedicineSchool of Biological SciencesFaculty of Biology, Medicine and HealthThe University of ManchesterManchester Academic Health Science Centre Manchester M13 9PL UK
| | - Julie E. Gough
- School of MaterialsThe University of Manchester Manchester M13 9PL UK
| | - Adam J. Reid
- Blond McIndoe LaboratoriesDivision of Cell Matrix Biology and Regenerative MedicineSchool of Biological SciencesFaculty of Biology, Medicine and HealthThe University of ManchesterManchester Academic Health Science Centre Manchester M13 9PL UK
- Department of Plastic Surgery and BurnsWythenshawe HospitalManchester University NHS Foundation TrustManchester Academic Health Science Centre Manchester M23 9LT UK
| | - Xu Li
- Institute of Materials Research and Engineering (IMRE)Agency for Science Technology and Research (A*STAR) 2 Fusionopolis, Way, Innovis #08‐03 Singapore 138634 Singapore
| | - Jonny J. Blaker
- Bio‐Active Materials GroupSchool of MaterialsMSS TowerThe University of Manchester Manchester M13 9PL UK
- School of MaterialsThe University of Manchester Manchester M13 9PL UK
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13
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Sarker M, Naghieh S, McInnes AD, Schreyer DJ, Chen X. Regeneration of peripheral nerves by nerve guidance conduits: Influence of design, biopolymers, cells, growth factors, and physical stimuli. Prog Neurobiol 2018; 171:125-150. [DOI: 10.1016/j.pneurobio.2018.07.002] [Citation(s) in RCA: 108] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Revised: 07/24/2018] [Accepted: 07/26/2018] [Indexed: 01/10/2023]
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14
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Grasman JM, Ferreira JA, Kaplan DL. Tissue Models for Neurogenesis and Repair in 3D. ADVANCED FUNCTIONAL MATERIALS 2018; 28:1803822. [PMID: 32440261 PMCID: PMC7241596 DOI: 10.1002/adfm.201803822] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Development and maturation of vascular and neuronal tissues occurs simultaneously in utero, and are regulated by significant crosstalk. We report on the development of a 3D tissue system to model neurogenesis and recapitulate developmental signaling conditions. Human umbilical vein endothelial cells (HUVECs) were seeded inside channels within collagen gels to represent nascent vascular networks. Axons extending from chicken dorsal root ganglia (DRGs) grew significantly longer and preferentially towards the HUVEC seeded channels with respect to unloaded channels. To replicate these findings without the vascular component, channels were loaded with brain-derived neurotrophic factor (BDNF), the principle signaling molecule in HUVEC-stimulated axonal growth, and axons likewise were significantly longer and grew preferentially towards the BDNF-loaded channels with respect to controls. This 3D tissue system was then used as an in vitro replicate for peripheral nerve injury, with neural repair observed within 2 weeks. These results demonstrate that our 3D tissue system can model neural network formation, repair after laceration injuries, and can be utilized to further study how these networks form and interact with other tissues, such as skin or skeletal muscle.
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Affiliation(s)
| | | | - David L. Kaplan
- Address Correspondence to: David L. Kaplan, Ph.D., Department of Biomedical Engineering, Tufts University, 4 Colby St, Medford, MA, 02155, Tel: 617-627-3251, Fax: 617-627-3231,
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15
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Wang ZZ, Wood MD, Mackinnon SE, Sakiyama-Elbert SE. A microfluidic platform to study the effects of GDNF on neuronal axon entrapment. J Neurosci Methods 2018; 308:183-191. [PMID: 30081039 DOI: 10.1016/j.jneumeth.2018.08.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Revised: 08/01/2018] [Accepted: 08/02/2018] [Indexed: 12/23/2022]
Abstract
BACKGROUND One potential treatment strategy to enhance axon regeneration is transplanting Schwann Cells (SCs) that overexpress glial cell line-derived neurotrophic factor (GDNF). Unfortunately, constitutive GDNF overexpression in vivo can result in failure of regenerating axons to extend beyond the GDNF source, a phenomenon termed the "candy-store" effect. Little is known about the mechanism of this axon entrapment in vivo. NEW METHOD We present a reproducible in vitro culture platform using a microfluidic device to model axon entrapment and investigate mechanisms by which GDNF causes axon entrapment. The device is comprised of three culture chambers connected by two sets of microchannels, which prevent cell soma from moving between chambers but allow neurites to grow between chambers. Neurons from dorsal root ganglia were seeded in one end chamber while the effect of different conditions in the other two chambers was used to study neurite entrapment. RESULTS The results showed that GDNF-overexpressing SCs (G-SCs) can induce axon entrapment in vitro. We also found that while physiological levels of GDNF (100 ng/mL) promoted neurite extension, supra-physiological levels of GDNF (700 ng/mL) induced axon entrapment. COMPARISON WITH EXISTING METHOD All previous work related to the "candy-store" effect were done in vivo. Here, we report the first in vitro platform that can recapitulate the axonal entrapment and investigate the mechanism of the phenomenon. CONCLUSIONS This platform facilitates investigation of the "candy-store" effect and shows the effects of high GDNF concentrations on neurite outgrowth.
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Affiliation(s)
- Ze Zhong Wang
- Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, MO, United States
| | - Matthew D Wood
- Division of Plastic and Reconstructive Surgery, Department of Surgery, Washington University School of Medicine, St. Louis, MO, United States
| | - Susan E Mackinnon
- Division of Plastic and Reconstructive Surgery, Department of Surgery, Washington University School of Medicine, St. Louis, MO, United States
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16
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Lecomte A, Descamps E, Bergaud C. A review on mechanical considerations for chronically-implanted neural probes. J Neural Eng 2018; 15:031001. [DOI: 10.1088/1741-2552/aa8b4f] [Citation(s) in RCA: 100] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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17
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Marquardt LM, Ee X, Iyer N, Hunter D, Mackinnon SE, Wood MD, Sakiyama-Elbert SE. Finely Tuned Temporal and Spatial Delivery of GDNF Promotes Enhanced Nerve Regeneration in a Long Nerve Defect Model. Tissue Eng Part A 2016; 21:2852-64. [PMID: 26466815 DOI: 10.1089/ten.tea.2015.0311] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
The use of growth factors, such as glial cell line-derived neurotrophic factor (GDNF), for the treatment of peripheral nerve injury has been useful in promoting axon survival and regeneration. Unfortunately, finding a method that delivers the appropriate spatial and temporal release profile to promote functional recovery has proven difficult. Some release methods result in burst release profiles too short to remain effective over the regeneration period; however, prolonged exposure to GDNF can result in axonal entrapment at the site of release. Thus, GDNF was delivered in both a spatially and temporally controlled manner using a two-phase system comprised of an affinity-based release system and conditional lentiviral GDNF overexpression from Schwann cells (SCs). Briefly, SCs were transduced with a tetracycline-inducible (Tet-On) GDNF overexpressing lentivirus before transplantation. Three-centimeter acellular nerve allografts (ANAs) were modified by injection of a GDNF-releasing fibrin scaffold under the epineurium and then used to bridge a 3 cm sciatic nerve defect. To encourage growth past the ANA, GDNF-SCs were transplanted into the distal nerve and doxycycline was administered for 4, 6, or 8 weeks to determine the optimal duration of GDNF expression in the distal nerve. Live imaging and histomorphometric analysis determined that 6 weeks of doxycycline treatment resulted in enhanced regeneration compared to 4 or 8 weeks. This enhanced regeneration resulted in increased gastrocnemius and tibialis anterior muscle mass for animals receiving doxycycline for 6 weeks. The results of this study demonstrate that strategies providing spatial and temporal control of delivery can improve axonal regeneration and functional muscle reinnervation.
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Affiliation(s)
- Laura M Marquardt
- 1 Department of Biomedical Engineering, Washington University in St. Louis , St. Louis, Missouri
| | - Xueping Ee
- 2 Divison of Plastic and Reconstructive Surgery, Department of Surgery, Washington University School of Medicine , St. Louis, Missouri
| | - Nisha Iyer
- 1 Department of Biomedical Engineering, Washington University in St. Louis , St. Louis, Missouri
| | - Daniel Hunter
- 2 Divison of Plastic and Reconstructive Surgery, Department of Surgery, Washington University School of Medicine , St. Louis, Missouri
| | - Susan E Mackinnon
- 2 Divison of Plastic and Reconstructive Surgery, Department of Surgery, Washington University School of Medicine , St. Louis, Missouri
| | - Matthew D Wood
- 2 Divison of Plastic and Reconstructive Surgery, Department of Surgery, Washington University School of Medicine , St. Louis, Missouri
| | - Shelly E Sakiyama-Elbert
- 1 Department of Biomedical Engineering, Washington University in St. Louis , St. Louis, Missouri.,2 Divison of Plastic and Reconstructive Surgery, Department of Surgery, Washington University School of Medicine , St. Louis, Missouri
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18
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Approaches to Peripheral Nerve Repair: Generations of Biomaterial Conduits Yielding to Replacing Autologous Nerve Grafts in Craniomaxillofacial Surgery. BIOMED RESEARCH INTERNATIONAL 2016; 2016:3856262. [PMID: 27556032 PMCID: PMC4983313 DOI: 10.1155/2016/3856262] [Citation(s) in RCA: 113] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/07/2016] [Accepted: 06/29/2016] [Indexed: 01/09/2023]
Abstract
Peripheral nerve injury is a common clinical entity, which may arise due to traumatic, tumorous, or even iatrogenic injury in craniomaxillofacial surgery. Despite advances in biomaterials and techniques over the past several decades, reconstruction of nerve gaps remains a challenge. Autografts are the gold standard for nerve reconstruction. Using autografts, there is donor site morbidity, subsequent sensory deficit, and potential for neuroma development and infection. Moreover, the need for a second surgical site and limited availability of donor nerves remain a challenge. Thus, increasing efforts have been directed to develop artificial nerve guidance conduits (ANCs) as new methods to replace autografts in the future. Various synthetic conduit materials have been tested in vitro and in vivo, and several first- and second-generation conduits are FDA approved and available for purchase, while third-generation conduits still remain in experimental stages. This paper reviews the current treatment options, summarizes the published literature, and assesses future prospects for the repair of peripheral nerve injury in craniomaxillofacial surgery with a particular focus on facial nerve regeneration.
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19
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Tomblyn S, Kneller EP, Walker SJ, Ellenburg MD, Kowalczewski CJ, Van Dyke M, Burnett L, Saul JM. Keratin hydrogel carrier system for simultaneous delivery of exogenous growth factors and muscle progenitor cells. J Biomed Mater Res B Appl Biomater 2016; 104:864-79. [PMID: 25953729 PMCID: PMC5565163 DOI: 10.1002/jbm.b.33438] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2014] [Revised: 01/14/2015] [Accepted: 03/30/2015] [Indexed: 11/10/2022]
Abstract
Ideal material characteristics for tissue engineering or regenerative medicine approaches to volumetric muscle loss (VML) include the ability to deliver cells, growth factors, and molecules that support tissue formation from a system with a tunable degradation profile. Two different types of human hair-derived keratins were tested as options to fulfill these VML design requirements: (1) oxidatively extracted keratin (keratose) characterized by a lack of covalent crosslinking between cysteine residues, and (2) reductively extracted keratin (kerateine) characterized by disulfide crosslinks. Human skeletal muscle myoblasts cultured on coatings of both types of keratin had increased numbers of multinucleated cells compared to collagen or Matrigel(TM) and adhesion levels greater than collagen. Rheology showed elastic moduli from 10(2) to 10(5) Pa and viscous moduli from 10(1) to 10(4) Pa depending on gel concentration and keratin type. Kerateine and keratose showed differing rates of degradation due to the presence or absence of disulfide crosslinks, which likely contributed to observed differences in release profiles of several growth factors. In vivo testing in a subcutaneous mouse model showed that keratose hydrogels can be used to deliver mouse muscle progenitor cells and growth factors. Histological assessment showed minimal inflammatory responses and an increase in markers of muscle formation. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 864-879, 2016.
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Affiliation(s)
- Seth Tomblyn
- KeraNetics, LLC, Suite 168, 391 Technology Way, Winston-Salem, NC 27101
| | | | - Stephen J. Walker
- Wake Forest Institute for Regenerative Medicine, Wake Forest University Health Sciences, Winston-Salem, NC 27157
| | - Mary D. Ellenburg
- KeraNetics, LLC, Suite 168, 391 Technology Way, Winston-Salem, NC 27101
| | - Christine J. Kowalczewski
- Virginia Tech-Wake Forest University School of Biomedical Engineering and Sciences, Blacksburg, VA 24061
- Department of Chemical, Paper, and Biomedical Engineering, Miami University, Oxford, OH 45056
| | - Mark Van Dyke
- Virginia Tech-Wake Forest University School of Biomedical Engineering and Sciences, Blacksburg, VA 24061
| | - Luke Burnett
- KeraNetics, LLC, Suite 168, 391 Technology Way, Winston-Salem, NC 27101
| | - Justin M. Saul
- Department of Chemical, Paper, and Biomedical Engineering, Miami University, Oxford, OH 45056
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20
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Johnson BN, Lancaster KZ, Zhen G, He J, Gupta MK, Kong YL, Engel EA, Krick KD, Ju A, Meng F, Enquist LW, Jia X, McAlpine MC. 3D Printed Anatomical Nerve Regeneration Pathways. ADVANCED FUNCTIONAL MATERIALS 2015; 25:6205-6217. [PMID: 26924958 PMCID: PMC4765385 DOI: 10.1002/adfm.201501760] [Citation(s) in RCA: 170] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
An imaging-coupled 3D printing methodology for the design, optimization, and fabrication of a customized nerve repair technology for complex injuries is presented. The custom scaffolds are deterministically fabricated via a microextrusion printing principle which enables the simultaneous incorporation of anatomical geometries, biomimetic physical cues, and spatially controlled biochemical gradients in a one-pot 3D manufacturing approach.
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Affiliation(s)
- Blake N. Johnson
- Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey 08544, United States, Department of Industrial and Systems Engineering, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - Karen Z. Lancaster
- Department of Molecular Biology and Princeton Neuroscience Institute, Princeton University, Princeton, New Jersey 08544, United States
| | - Gehua Zhen
- Department of Orthopedic Surgery, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, United States
| | - Junyun He
- Department of Neurosurgery, University of Maryland School of Medicine, Baltimore, Maryland 21201, United States
| | - Maneesh K. Gupta
- Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey 08544, United States
| | - Yong Lin Kong
- Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey 08544, United States
| | - Esteban A. Engel
- Department of Molecular Biology and Princeton Neuroscience Institute, Princeton University, Princeton, New Jersey 08544, United States
| | - Kellin D. Krick
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, United States
| | - Alex Ju
- Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey 08544, United States
| | - Fanben Meng
- Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey 08544, United States
| | - Lynn W. Enquist
- Department of Molecular Biology and Princeton Neuroscience Institute, Princeton University, Princeton, New Jersey 08544, United States
| | - Xiaofeng Jia
- Department of Neurosurgery, Orthopedics, University of Maryland School of Medicine, Baltimore, Maryland 21201, United States, Department of Biomedical Engineering, Anesthesiology and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, United States
| | - Michael C. McAlpine
- Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey 08544, United States, Department of Mechanical Engineering, University of Minnesota, Minneapolis, Minnesota 55455, United States
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21
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Silk-tropoelastin protein films for nerve guidance. Acta Biomater 2015; 14:1-10. [PMID: 25481743 DOI: 10.1016/j.actbio.2014.11.045] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2014] [Revised: 11/16/2014] [Accepted: 11/24/2014] [Indexed: 12/24/2022]
Abstract
Peripheral nerve regeneration may be enhanced through the use of biodegradable thin film biomaterials as highly tuned inner nerve conduit liners. Dorsal root ganglion neuron and Schwann cell responses were studied on protein films comprising silk fibroin blended with recombinant human tropoelastin protein. Tropoelastin significantly improved neurite extension and enhanced Schwann cell process length and cell area, while the silk provided a robust biomaterial template. Silk-tropoelastin blends afforded a 2.4-fold increase in neurite extension, when compared to silk films coated with poly-d-lysine. When patterned by drying on grooved polydimethylsiloxane (3.5 μm groove width, 0.5 μm groove depth), these protein blends induced both neurite and Schwann cell process alignment. Neurons were functional as assessed using patch-clamping, and displayed action potentials similar to those cultured on poly(lysine)-coated glass. Taken together, silk-tropoelastin films offer useful biomaterial interfacial platforms for nerve cell control, which can be considered for neurite guidance, disease models for neuropathies and surgical peripheral nerve repairs.
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22
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Hopkins AM, DeSimone E, Chwalek K, Kaplan DL. 3D in vitro modeling of the central nervous system. Prog Neurobiol 2015; 125:1-25. [PMID: 25461688 PMCID: PMC4324093 DOI: 10.1016/j.pneurobio.2014.11.003] [Citation(s) in RCA: 145] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2014] [Revised: 10/12/2014] [Accepted: 11/15/2014] [Indexed: 12/15/2022]
Abstract
There are currently more than 600 diseases characterized as affecting the central nervous system (CNS) which inflict neural damage. Unfortunately, few of these conditions have effective treatments available. Although significant efforts have been put into developing new therapeutics, drugs which were promising in the developmental phase have high attrition rates in late stage clinical trials. These failures could be circumvented if current 2D in vitro and in vivo models were improved. 3D, tissue-engineered in vitro systems can address this need and enhance clinical translation through two approaches: (1) bottom-up, and (2) top-down (developmental/regenerative) strategies to reproduce the structure and function of human tissues. Critical challenges remain including biomaterials capable of matching the mechanical properties and extracellular matrix (ECM) composition of neural tissues, compartmentalized scaffolds that support heterogeneous tissue architectures reflective of brain organization and structure, and robust functional assays for in vitro tissue validation. The unique design parameters defined by the complex physiology of the CNS for construction and validation of 3D in vitro neural systems are reviewed here.
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Affiliation(s)
- Amy M Hopkins
- Department of Biomedical Engineering, Tufts University, Science & Technology Center, 4 Colby Street, Medford, MA 02155, USA
| | - Elise DeSimone
- Department of Biomedical Engineering, Tufts University, Science & Technology Center, 4 Colby Street, Medford, MA 02155, USA
| | - Karolina Chwalek
- Department of Biomedical Engineering, Tufts University, Science & Technology Center, 4 Colby Street, Medford, MA 02155, USA
| | - David L Kaplan
- Department of Biomedical Engineering, Tufts University, Science & Technology Center, 4 Colby Street, Medford, MA 02155, USA.
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23
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Marquardt LM, Sakiyama-Elbert SE. GDNF preconditioning can overcome Schwann cell phenotypic memory. Exp Neurol 2014; 265:1-7. [PMID: 25496841 DOI: 10.1016/j.expneurol.2014.12.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2014] [Revised: 11/25/2014] [Accepted: 12/03/2014] [Indexed: 01/26/2023]
Abstract
While it is known that Schwann cells (SCs) provide cues to enhance regeneration following peripheral nerve injury, the effect of SC phenotypic memory (muscle or cutaneous nerve-derived) on enhancing axonal regeneration and functional recovery has been unclear in the literature. In particular, differences between muscle and cutaneous nerve-derived SC may encourage specific motor or sensory axonal guidance in cell/tissue transplantation therapies. Thus, the goal of this study was to determine whether phenotypically matched combinations of neurons and SCs stimulate greater axonal extension compared to mismatched combinations (i.e. motor neurons/muscle nerve-derived SCs vs. motor neurons/cutaneous nerve-derived SCs). Additionally, the effect of glial cell line-derived neurotrophic factor (GDNF) treatment on SC-neuron interaction was also evaluated. In order to examine these interactions, microfluidic devices were used to assess the effects of soluble factors secreted from SCs on neurons. Unlike traditional co-culture methods, the devices allow for easier quantification of single neurite extension over long periods of time, as well as easy cell and media sampling of pure populations for biochemical analyses. Results demonstrated longer neurite growth when neurons are cultured with phenotype matched SCs, suggesting that SCs are capable of retaining phenotypic memory despite a prolonged absence of axonal contact. Furthermore, the negative effect of mismatched cultures can be overcome when mismatched SCs are preconditioned with GDNF. These results suggest that treatment of SCs with GDNF could enhance their ability to promote regeneration through mismatched grafts frequently used in clinical settings.
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Affiliation(s)
- Laura M Marquardt
- Department of Biomedical Engineering, Washington University in St. Louis, Saint Louis, MO, USA
| | - Shelly E Sakiyama-Elbert
- Department of Biomedical Engineering, Washington University in St. Louis, Saint Louis, MO, USA; Division of Plastic and Reconstructive Surgery, Washington University School of Medicine, Saint Louis, MO, USA.
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24
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Sivak WN, White JD, Bliley JM, Tien LW, Liao HT, Kaplan DL, Marra KG. Delivery of chondroitinase ABC and glial cell line-derived neurotrophic factor from silk fibroin conduits enhances peripheral nerve regeneration. J Tissue Eng Regen Med 2014; 11:733-742. [PMID: 25424415 DOI: 10.1002/term.1970] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2014] [Revised: 09/18/2014] [Accepted: 10/27/2014] [Indexed: 01/26/2023]
Abstract
Nerve conduits are a proven strategy for guiding axon regrowth following injury. This study compares degradable silk-trehalose films containing chondroitinase ABC (ChABC) and/or glial cell line-derived neurotrophic factor (GDNF) loaded within a silk fibroin-based nerve conduit in a rat sciatic nerve defect model. Four groups of silk conduits were prepared, with the following silk-trehalose films inserted into the conduit: (a) empty; (b) 1 µg GDNF; (3) 2 U ChABC; and (4) 1 µg GDNF/2 U ChABC. Drug release studies demonstrated 20% recovery of GDNF and ChABC at 6 weeks and 24 h, respectively. Six conduits of each type were implanted into 15 mm sciatic nerve defects in Lewis rats; conduits were explanted for histological analysis at 6 weeks. Tissues stained with Schwann cell S-100 antibody demonstrated an increased density of cells in both GDNF- and ChABC-treated groups compared to empty control conduits (p < 0.05). Conduits loaded with GDNF and ChABC also demonstrated higher levels of neuron-specific PGP 9.5 protein when compared to controls (p < 0.05). In this study we demonstrated a method to enhance Schwann cell migration and proliferation and also foster axonal regeneration when repairing peripheral nerve gap defects. Silk fibroin-based nerve conduits possess favourable mechanical and degradative properties and are further enhanced when loaded with ChABC and GDNF. Copyright © 2014 John Wiley & Sons, Ltd.
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Affiliation(s)
- Wesley N Sivak
- Department of Plastic Surgery, University of Pittsburgh, PA, USA
| | - James D White
- Department of Biomedical Engineering, Tufts University, Boston, MA, USA
| | | | - Lee W Tien
- Department of Biomedical Engineering, Tufts University, Boston, MA, USA
| | - Han Tsung Liao
- Department of Plastic Surgery, University of Pittsburgh, PA, USA
- Department of Plastic and Reconstructive Surgery, Craniofacial Research Centre, Chang Gung Memorial Hospital, College of Medicine, Chang Gung University, Taiwan
| | - David L Kaplan
- Department of Biomedical Engineering, Tufts University, Boston, MA, USA
| | - Kacey G Marra
- Department of Plastic Surgery, University of Pittsburgh, PA, USA
- Department of Bioengineering, University of Pittsburgh, PA, USA
- McGowan Institute for Regenerative Medicine, Pittsburgh, PA, USA
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25
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Yucel T, Lovett ML, Kaplan DL. Silk-based biomaterials for sustained drug delivery. J Control Release 2014; 190:381-97. [PMID: 24910193 PMCID: PMC4142080 DOI: 10.1016/j.jconrel.2014.05.059] [Citation(s) in RCA: 212] [Impact Index Per Article: 21.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2014] [Revised: 05/24/2014] [Accepted: 05/28/2014] [Indexed: 10/25/2022]
Abstract
Silk presents a rare combination of desirable properties for sustained drug delivery, including aqueous-based purification and processing options without chemical cross-linkers, compatibility with common sterilization methods, controllable and surface-mediated biodegradation into non-inflammatory by-products, biocompatibility, utility in drug stabilization, and robust mechanical properties. A versatile silk-based toolkit is currently available for sustained drug delivery formulations of small molecule through macromolecular drugs, with a promise to mitigate several drawbacks associated with other degradable sustained delivery technologies in the market. Silk-based formulations utilize silk's well-defined nano- through microscale structural hierarchy, stimuli-responsive self-assembly pathways and crystal polymorphism, as well as sequence and genetic modification options towards targeted pharmaceutical outcomes. Furthermore, by manipulating the interactions between silk and drug molecules, near-zero order sustained release may be achieved through diffusion- and degradation-based release mechanisms. Because of these desirable properties, there has been increasing industrial interest in silk-based drug delivery systems currently at various stages of the developmental pipeline from pre-clinical to FDA-approved products. Here, we discuss the unique aspects of silk technology as a sustained drug delivery platform and highlight the current state of the art in silk-based drug delivery. We also offer a potential early development pathway for silk-based sustained delivery products.
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Affiliation(s)
- Tuna Yucel
- Tufts University, Department of Biomedical Engineering, Medford, MA 02155, USA; Ekteino Laboratories, New York, NY 10022, USA
| | - Michael L Lovett
- Tufts University, Department of Biomedical Engineering, Medford, MA 02155, USA; Ekteino Laboratories, New York, NY 10022, USA
| | - David L Kaplan
- Tufts University, Department of Biomedical Engineering, Medford, MA 02155, USA
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Ramburrun P, Kumar P, Choonara YE, Bijukumar D, du Toit LC, Pillay V. A review of bioactive release from nerve conduits as a neurotherapeutic strategy for neuronal growth in peripheral nerve injury. BIOMED RESEARCH INTERNATIONAL 2014; 2014:132350. [PMID: 25143934 PMCID: PMC4131113 DOI: 10.1155/2014/132350] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/21/2014] [Accepted: 05/04/2014] [Indexed: 02/07/2023]
Abstract
Peripheral nerve regeneration strategies employ the use of polymeric engineered nerve conduits encompassed with components of a delivery system. This allows for the controlled and sustained release of neurotrophic growth factors for the enhancement of the innate regenerative capacity of the injured nerves. This review article focuses on the delivery of neurotrophic factors (NTFs) and the importance of the parameters that control release kinetics in the delivery of optimal quantities of NTFs for improved therapeutic effect and prevention of dose dumping. Studies utilizing various controlled-release strategies, in attempt to obtain ideal release kinetics, have been reviewed in this paper. Release strategies discussed include affinity-based models, crosslinking techniques, and layer-by-layer technologies. Currently available synthetic hollow nerve conduits, an alternative to the nerve autografts, have proven to be successful in the bridging and regeneration of primarily the short transected nerve gaps in several patient cases. However, current research emphasizes on the development of more advanced nerve conduits able to simulate the effectiveness of the autograft which includes, in particular, the ability to deliver growth factors.
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Affiliation(s)
- Poornima Ramburrun
- Wits Advanced Drug Delivery Platform Research Unit, Department of Pharmacy and Pharmacology, School of Therapeutic Sciences, Faculty of Health Sciences, University of the Witwatersrand, 7 York Road, Parktown, Johannesburg 2193, South Africa
| | - Pradeep Kumar
- Wits Advanced Drug Delivery Platform Research Unit, Department of Pharmacy and Pharmacology, School of Therapeutic Sciences, Faculty of Health Sciences, University of the Witwatersrand, 7 York Road, Parktown, Johannesburg 2193, South Africa
| | - Yahya E. Choonara
- Wits Advanced Drug Delivery Platform Research Unit, Department of Pharmacy and Pharmacology, School of Therapeutic Sciences, Faculty of Health Sciences, University of the Witwatersrand, 7 York Road, Parktown, Johannesburg 2193, South Africa
| | - Divya Bijukumar
- Wits Advanced Drug Delivery Platform Research Unit, Department of Pharmacy and Pharmacology, School of Therapeutic Sciences, Faculty of Health Sciences, University of the Witwatersrand, 7 York Road, Parktown, Johannesburg 2193, South Africa
| | - Lisa C. du Toit
- Wits Advanced Drug Delivery Platform Research Unit, Department of Pharmacy and Pharmacology, School of Therapeutic Sciences, Faculty of Health Sciences, University of the Witwatersrand, 7 York Road, Parktown, Johannesburg 2193, South Africa
| | - Viness Pillay
- Wits Advanced Drug Delivery Platform Research Unit, Department of Pharmacy and Pharmacology, School of Therapeutic Sciences, Faculty of Health Sciences, University of the Witwatersrand, 7 York Road, Parktown, Johannesburg 2193, South Africa
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27
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Challenges for nerve repair using chitosan-siloxane hybrid porous scaffolds. BIOMED RESEARCH INTERNATIONAL 2014; 2014:153808. [PMID: 25054129 PMCID: PMC4087280 DOI: 10.1155/2014/153808] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/07/2014] [Revised: 05/29/2014] [Accepted: 05/31/2014] [Indexed: 01/02/2023]
Abstract
The treatment of peripheral nerve injuries remains one of the greatest challenges of neurosurgery, as functional recover is rarely satisfactory in these patients. Recently, biodegradable nerve guides have shown great potential for enhancing nerve regeneration. A major advantage of these nerve guides is that no foreign material remains after the device has fulfilled its task, which spares a second surgical intervention. Recently, we studied peripheral nerve regeneration using chitosan-γ-glycidoxypropyltrimethoxysilane (chitosan-GPTMS) porous hybrid membranes. In our studies, these porous membranes significantly improved nerve fiber regeneration and functional recovery in rat models of axonotmetic and neurotmetic sciatic nerve injuries. In particular, the number of regenerated myelinated nerve fibers and myelin thickness were significantly higher in rat treated with chitosan porous hybrid membranes, whether or not they were used in combination with mesenchymal stem cells isolated from the Wharton's jelly of the umbilical cord. In this review, we describe our findings on the use of chitosan-GPTMS hybrids for nerve regeneration.
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28
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Abstract
Nerve injury secondary to trauma, neurological disease or tumor excision presents a challenge for surgical reconstruction. Current practice for nerve repair involves autologous nerve transplantation, which is associated with significant donor-site morbidity and other complications. Previously artificial nerve conduits made from polycaprolactone, polyglycolic acid and collagen were approved by the FDA (USA) for nerve repair. More recently, there have been significant advances in nerve conduit design that better address the requirements of nerve regrowth. Innovations in materials science, nanotechnology, and biology open the way for the synthesis of new generation nerve repair conduits that address issues currently faced in nerve repair and regeneration. This review discusses recent innovations in this area, including the use of nanotechnology to improve the design of nerve conduits and to enhance nerve regeneration.
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29
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Sivak WN, Bliley JM, Marra KG. Polymeric biomaterials for nerve regeneration: fabrication and implantation of a biodegradable nerve guide. Methods Mol Biol 2014; 1162:139-148. [PMID: 24838964 DOI: 10.1007/978-1-4939-0777-9_11] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Optimizing the quantity, quality, and speed of axon regeneration is important in maximizing functional outcomes following peripheral nerve injury. When severed, injured nerves must be able to regenerate and reconnect to the structures they previously controlled within 12-18 months before sensation and motion are permanently lost. Nerve sprouts from the proximal stump will spontaneously migrate toward the distal stump in the event of a nerve transection. However, surgical intervention remains necessary to repair transection injuries. Regeneration becomes particularly troublesome with large gaps, where autologous nerve grafts or nerve guides are used to repair transected nerves. Nerve conduits function as therapeutic adjuncts, guiding axonal regeneration across gap defects. Despite the availability of several FDA-approved nerve conduits, functional outcomes following their use remain less than optimal. Much work has been focused on developing nerve conduits to improve peripheral nerve repair outcomes. This chapter describes fabrication of a poly(caprolactone) nerve guide and demonstrates its use in a rat sciatic nerve model.
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Affiliation(s)
- Wesley N Sivak
- Department of Plastic Surgery, University of Pittsburgh, 200 Lothrop Street, 1655E BST, Pittsburgh, PA, USA
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30
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Lentiviral vector-mediated gradients of GDNF in the injured peripheral nerve: effects on nerve coil formation, Schwann cell maturation and myelination. PLoS One 2013; 8:e71076. [PMID: 23951085 PMCID: PMC3741360 DOI: 10.1371/journal.pone.0071076] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2013] [Accepted: 07/01/2013] [Indexed: 12/24/2022] Open
Abstract
Although the peripheral nerve is capable of regeneration, only a small minority of patients regain normal function after surgical reconstruction of a major peripheral nerve lesion, resulting in a severe and lasting negative impact on the quality of life. Glial cell-line derived neurotrophic factor (GDNF) has potent survival- and outgrowth-promoting effects on motoneurons, but locally elevated levels of GDNF cause trapping of regenerating axons and the formation of nerve coils. This phenomenon has been called the “candy store” effect. In this study we created gradients of GDNF in the sciatic nerve after a ventral root avulsion. This approach also allowed us to study the effect of increasing concentrations of GDNF on Schwann cell proliferation and morphology in the injured peripheral nerve. We demonstrate that lentiviral vectors can be used to create a 4 cm long GDNF gradient in the intact and lesioned rat sciatic nerve. Nerve coils were formed throughout the gradient and the number and size of the nerve coils increased with increasing GDNF levels in the nerve. In the nerve coils, Schwann cell density is increased, their morphology is disrupted and myelination of axons is severely impaired. The total number of regenerated and surviving motoneurons is not enhanced after the distal application of a GDNF gradient, but increased sprouting does result in higher number of motor axon in the distal segment of the sciatic nerve. These results show that lentiviral vector mediated overexpression of GDNF exerts multiple effects on both Schwann cells and axons and that nerve coil formation already occurs at relatively low concentrations of exogenous GDNF. Controlled expression of GDNF, by using a viral vector with regulatable GDNF expression, may be required to avoid motor axon trapping and to prevent the effects on Schwann cell proliferation and myelination.
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31
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Kar S, Talukdar S, Pal S, Nayak S, Paranjape P, Kundu SC. Silk gland fibroin from indian muga silkworm Antheraea assama as potential biomaterial. Tissue Eng Regen Med 2013. [DOI: 10.1007/s13770-012-0008-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
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Abstract
The theory of chemotaxis has been widely accepted, but its mechanisms are disputed. Chemotactic growth of peripheral nerves may be tissue, topographic and end-organ specific. Recent studies indicated that peripheral nerve regeneration lacks topographic specificity, but whether it has end-organ specificity is disputed. Chemotaxis in nerve regeneration is affected by the distance between stumps, volume, and neurotrophic support, as well as the structure of distal nerve stumps. It can be applied to achieve precise repair of nerves and complete recovery of end organ function. Small gap sleeve bridging technique, which is based on this theory shows promising effects but it is still challenging to find the perfect combination of nerve conduits, cells and neurotrophic factors to put it intoits best use. In this paper, we made a comprehensive review of mechanisms, effect factors and applications of chemotaxis.
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Hronik-Tupaj M, Raja WK, Tang-Schomer M, Omenetto FG, Kaplan DL. Neural responses to electrical stimulation on patterned silk films. J Biomed Mater Res A 2013; 101:2559-72. [PMID: 23401351 DOI: 10.1002/jbm.a.34565] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2012] [Revised: 12/15/2012] [Accepted: 12/18/2012] [Indexed: 12/21/2022]
Abstract
Peripheral nerve injury is a critical issue for patients with trauma. Following injury, incomplete axon regeneration or misguided axon innervation into tissue will result in loss of sensory and motor functions. The objective of this study was to examine axon outgrowth and axon alignment in response to surface patterning and electrical stimulation. To accomplish our objective, metal electrodes with dimensions of 1.5 mm × 4 cm, were sputter coated onto micropatterned silk protein films, with surface grooves 3.5 μm wide × 500 nm deep. P19 neurons were seeded on the patterned electronic silk films and stimulated at 120 mV, 1 kHz, for 45 min each day for 7 days. Responses were compared with neurons on flat electronic silk films, patterned silk films without stimulation, and flat silk films without stimulation. Significant alignment was found on the patterned film groups compared with the flat film groups. Axon outgrowth was greater (p < 0.05) on electronic films on days 5 and 7 compared with the unstimulated groups. In conclusion, electrical stimulation, at 120 mV, 1 kHz, for 45 min daily, in addition to surface patterning, of 3.5 μm wide × 500 nm deep grooves, offered control of nerve axon outgrowth and alignment.
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Affiliation(s)
- Marie Hronik-Tupaj
- Department of Biomedical Engineering, Science & Technology Center, Tufts University, Medford, Massachusetts 02155, USA
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34
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Lin YC, Marra KG. Injectable systems and implantable conduits for peripheral nerve repair. Biomed Mater 2012; 7:024102. [DOI: 10.1088/1748-6041/7/2/024102] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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35
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Madduri S, Gander B. Growth factor delivery systems and repair strategies for damaged peripheral nerves. J Control Release 2011; 161:274-82. [PMID: 22178593 DOI: 10.1016/j.jconrel.2011.11.036] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2011] [Revised: 11/29/2011] [Accepted: 11/30/2011] [Indexed: 11/28/2022]
Abstract
Artificial nerve conduits (NCs) are, in certain cases, instrumental for repairing damaged peripheral nerves, although therapeutic efficacy remains often suboptimal. Considerable efforts have been made to improve the therapeutic performance of NCs. This article reviews recent developments in NC-technology for peripheral nerve regeneration with a main focus on growth factors delivery systems and repair strategies. Commonly used materials for NC fabrication include collagen, silk fibroin, and biodegradable aliphatic polyesters. The basic NC structure, i.e., a hollow tube, can be manufactured by diverse methods: spinning mandrel technology, sheet rolling, injection-molding, freeze-drying, and electro-spinning. Polymeric and cellular delivery systems for growth factors can be integrated in the NC wall or within luminal structures such as gels, fibers, or biological materials providing binding affinity for the bioactive compounds. NCs with sustained growth factor delivery generally improve significantly the axonal outgrowth in nerve defect models, although restoration of sensory and motor functions remains inferior to that achieved with autologous nerve grafts. To improve therapeutic outcomes, further biofunctionalization of NCs will be needed, i.e., adjusting degradation kinetics of NC scaffolding to be compatible with axonal regeneration; delivering multiple growth factors at individually optimized kinetics; incorporating modality specific glial cells and furnishing NCs with guiding nanostructures.
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Affiliation(s)
- Srinivas Madduri
- Department of Urology, University Hospital Zurich, 8091 Zurich, Switzerland
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36
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Wang Y, Jia H, Li WY, Tong XJ, Liu GB, Kang SW. Synergistic effects of bone mesenchymal stem cells and chondroitinase ABC on nerve regeneration after acellular nerve allograft in rats. Cell Mol Neurobiol 2011; 32:361-71. [PMID: 22095068 DOI: 10.1007/s10571-011-9764-4] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2011] [Accepted: 10/11/2011] [Indexed: 12/23/2022]
Abstract
This study aimed to evaluate whether combination therapy of bone marrow stromal cells (BMSCs) transplantation and chondroitinase ABC (ChABC) treatment further enhances axonal regeneration and functional recovery after acellular nerve allograft repair of the sciatic nerve gap in rats. Eight Sprague-Dawley rats were used as nerve donors, and 32 Wistar rats were randomly divided into four groups: Group I: acellular rat sciatic nerve (ARSN) group; Group II: ChABC treatment; Group III: BMSCs transplantation; and Group IV: ChABC treatment and BMSCs transplantation. The results showed that compared with ARSN control group, BMSC transplantation promoted axonal regeneration, the secretion of neural trophic factors NGF, BDNF and axon angiogenesis in nerve graft. ChABC treatment degraded chondroitin sulfate proteoglycans in ARSN in vitro and in vivo and improved BMSCs survival in ARSN. The combination therapy caused much better beneficial effects evidenced by increasing sciatic function index, nerve conduction velocity, restoration rate of tibialis anterior wet muscle weight, and myelinated nerve number, but did not further boost the therapeutic effects on neurotrophic factor production, axon angiogenesis, and sensory functional recovery by BMSC transplantation. Taken together, for the first time, we demonstrate the synergistic effects of BMSC transplantation and BMSCs treatment on peripheral nerve regeneration, and our findings may help establish novel strategies for cell transplantation therapy for peripheral nerve injury.
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Affiliation(s)
- Ying Wang
- Department of Anatomy, College of Basic Medical Sciences, China Medical University, Shenyang, China
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