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Buckley C, Montgomery TR, Szank T, Major I. Hyaluronic acid hybrid formulations optimised for 3D printing of nerve conduits and the delivery of the novel neurotrophic-like compound tyrosol to enhance peripheral nerve regeneration via Schwann cell proliferation. Int J Pharm 2024; 661:124477. [PMID: 39013530 DOI: 10.1016/j.ijpharm.2024.124477] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Revised: 07/11/2024] [Accepted: 07/13/2024] [Indexed: 07/18/2024]
Abstract
Peripheral nerve injuries, predominantly affecting individuals aged 20-40, pose significant healthcare challenges, with current surgical methods often failing to achieve complete functional recovery. This study focuses on the development of 3D printed hydrogel nerve conduits using modified hyaluronic acid (HA) for potentially enhancing peripheral nerve regeneration. Hyaluronic acid was chemically altered with cysteamine HCl and methacrylic anhydride to create thiolated HA (HA-SH) and methacrylated HA (HA-MA), achieving a modification degree of approximately 20 %. This modification was crucial to maintain the receptor interaction of HA. The modified HA was rigorously tested to ensure cytocompatibility in neuronal and glial cell lines. Subsequently, various 3D printed HA formulations were evaluated, focusing on improving HA's inherent mechanical weaknesses. These formulations were assessed for cytotoxicity through direct contact and elution extract testing, confirming their safety over a 24-h period. Among the neurotrophic compounds tested, Tyrosol emerged as the most effective in promoting Schwann cell proliferation in vitro. The 3D printed HA system demonstrated proficiency in loading and releasing Tyrosol at physiological pH. The findings from this research highlight the promising role of 3D printed HA and Tyrosol in the field of nerve tissue engineering, offering a novel approach to peripheral nerve regeneration.
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Affiliation(s)
- Ciara Buckley
- PRISM Research Institute, Technological University of the Shannon, Athlone N37 HD68, Ireland
| | - Therese R Montgomery
- School of Science and Computing, Atlantic Technological University, Galway H91 T8NW, Ireland
| | - Tomasz Szank
- Bioscience Research Institute, Technological University of the Shannon, Athlone N37 HD68, Ireland
| | - Ian Major
- PRISM Research Institute, Technological University of the Shannon, Athlone N37 HD68, Ireland.
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2
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Chouhan D, Gordián Vélez WJ, Struzyna LA, Adewole DO, Cullen ER, Burrell JC, O’Donnell JC, Cullen DK. Generation of contractile forces by three-dimensional bundled axonal tracts in micro-tissue engineered neural networks. Front Mol Neurosci 2024; 17:1346696. [PMID: 38590432 PMCID: PMC10999686 DOI: 10.3389/fnmol.2024.1346696] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Accepted: 02/28/2024] [Indexed: 04/10/2024] Open
Abstract
Axonal extension and retraction are ongoing processes that occur throughout all developmental stages of an organism. The ability of axons to produce mechanical forces internally and respond to externally generated forces is crucial for nervous system development, maintenance, and plasticity. Such axonal mechanobiological phenomena have typically been evaluated in vitro at a single-cell level, but these mechanisms have not been studied when axons are present in a bundled three-dimensional (3D) form like in native tissue. In an attempt to emulate native cortico-cortical interactions under in vitro conditions, we present our approach to utilize previously described micro-tissue engineered neural networks (micro-TENNs). Here, micro-TENNs were comprised of discrete populations of rat cortical neurons that were spanned by 3D bundled axonal tracts and physically integrated with each other. We found that these bundled axonal tracts inherently exhibited an ability to generate contractile forces as the microtissue matured. We therefore utilized this micro-TENN testbed to characterize the intrinsic contractile forces generated by the integrated axonal tracts in the absence of any external force. We found that contractile forces generated by bundled axons were dependent on microtubule stability. Moreover, these intra-axonal contractile forces could simultaneously generate tensile forces to induce so-called axonal "stretch-growth" in different axonal tracts within the same microtissue. The culmination of axonal contraction generally occurred with the fusion of both the neuronal somatic regions along the axonal tracts, therefore perhaps showing the innate tendency of cortical neurons to minimize their wiring distance, a phenomenon also perceived during brain morphogenesis. In future applications, this testbed may be used to investigate mechanisms of neuroanatomical development and those underlying certain neurodevelopmental disorders.
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Affiliation(s)
- Dimple Chouhan
- Department of Neurosurgery, Center for Brain Injury and Repair, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
- Center for Neurotrauma, Neurodegeneration and Restoration, Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, United States
| | - Wisberty J. Gordián Vélez
- Department of Neurosurgery, Center for Brain Injury and Repair, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
- Center for Neurotrauma, Neurodegeneration and Restoration, Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, United States
- Department of Bioengineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, PA, United States
| | - Laura A. Struzyna
- Department of Neurosurgery, Center for Brain Injury and Repair, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
- Center for Neurotrauma, Neurodegeneration and Restoration, Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, United States
- Department of Bioengineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, PA, United States
| | - Dayo O. Adewole
- Department of Neurosurgery, Center for Brain Injury and Repair, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
- Center for Neurotrauma, Neurodegeneration and Restoration, Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, United States
- Department of Bioengineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, PA, United States
| | - Erin R. Cullen
- Department of Neurosurgery, Center for Brain Injury and Repair, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
- Center for Neurotrauma, Neurodegeneration and Restoration, Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, United States
| | - Justin C. Burrell
- Department of Neurosurgery, Center for Brain Injury and Repair, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
- Center for Neurotrauma, Neurodegeneration and Restoration, Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, United States
| | - John C. O’Donnell
- Department of Neurosurgery, Center for Brain Injury and Repair, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
- Center for Neurotrauma, Neurodegeneration and Restoration, Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, United States
| | - D. Kacy Cullen
- Department of Neurosurgery, Center for Brain Injury and Repair, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
- Center for Neurotrauma, Neurodegeneration and Restoration, Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, United States
- Department of Bioengineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, PA, United States
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Burrell JC, Vu PT, Alcott OJB, Toro CA, Cardozo C, Cullen DK. Orally administered boldine reduces muscle atrophy and promotes neuromuscular recovery in a rodent model of delayed nerve repair. Front Cell Neurosci 2023; 17:1240916. [PMID: 37829672 PMCID: PMC10565860 DOI: 10.3389/fncel.2023.1240916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Accepted: 09/01/2023] [Indexed: 10/14/2023] Open
Abstract
Peripheral nerve injury often results in poor functional recovery due to a prolonged period of muscle denervation. In particular, absent axonal contact, denervated muscle can undergo irrevocable atrophy and diminished receptiveness for reinnervation over time, ultimately reducing the likelihood for meaningful neuromuscular recovery. While innovative surgical approaches can minimize the harmful effects of denervation by re-routing neighboring-otherwise uninjured-axons, there are no clinically-available approaches to preserve the reinnervation capacity of denervated muscles. Blocking intramuscular connexin hemichannel formation has been reported to improve muscle innervation in vitro and prevent atrophy in vivo. Therefore, the current study investigated the effects of orally administered boldine, a connexin hemichannel inhibitor, on denervated-related muscle changes and nerve regeneration in a rat model of delayed peripheral nerve repair. We found that daily boldine administration significantly enhanced an evoked response in the tibialis anterior muscle at 2 weeks after common peroneal nerve transection, and decreased intramuscular connexin 43 and 45 expression, intraneural Schwann cell expression of connexin 43, and muscle fiber atrophy up to 4 weeks post transection. Additional animals underwent a cross nerve repair procedure (tibial to common peroneal neurorrhaphy) at 4 weeks following the initial transection injury. Here, we found elevated nerve electrophysiological activity and greater muscle fiber maturation at 6 weeks post repair in boldine treated animals. These findings suggest that boldine may be a promising pharmacological approach to minimize the deleterious effects of prolonged denervation and, with further optimization, may improve levels of functional recovery following nerve repair.
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Affiliation(s)
- Justin C. Burrell
- Department of Neurosurgery, Center for Brain Injury and Repair, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
- Center for Neurotrauma, Neurodegeneration and Restoration, CMC VA Medical Center, Philadelphia, PA, United States
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, United States
| | - Phuong T. Vu
- Center for Neurotrauma, Neurodegeneration and Restoration, CMC VA Medical Center, Philadelphia, PA, United States
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, United States
| | - Owen J. B. Alcott
- Department of Biochemistry, Widener University, Philadelphia, PA, United States
| | - Carlos A. Toro
- Spinal Cord Damage Research Center, James J. Peters VA Medical Center, Bronx, NY, United States
- Icahn School of Medicine, Mount Sinai, New York, NY, United States
| | - Christopher Cardozo
- Spinal Cord Damage Research Center, James J. Peters VA Medical Center, Bronx, NY, United States
- Icahn School of Medicine, Mount Sinai, New York, NY, United States
| | - D. Kacy Cullen
- Department of Neurosurgery, Center for Brain Injury and Repair, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
- Center for Neurotrauma, Neurodegeneration and Restoration, CMC VA Medical Center, Philadelphia, PA, United States
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, United States
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4
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Ye H, Chen J, Li YQ, Yang J, Hsu CC, Cao TT. A hyaluronic acid granular hydrogel nerve guidance conduit promotes regeneration and functional recovery of injured sciatic nerves in rats. Neural Regen Res 2023; 18:657-663. [DOI: 10.4103/1673-5374.350212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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Burrell JC, Das S, Laimo FA, Katiyar KS, Browne KD, Shultz RB, Tien VJ, Vu PT, Petrov D, Ali ZS, Rosen JM, Cullen DK. Engineered neuronal microtissue provides exogenous axons for delayed nerve fusion and rapid neuromuscular recovery in rats. Bioact Mater 2022; 18:339-353. [PMID: 35415305 PMCID: PMC8965778 DOI: 10.1016/j.bioactmat.2022.03.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Revised: 02/18/2022] [Accepted: 03/11/2022] [Indexed: 11/24/2022] Open
Abstract
Nerve injury requiring surgical repair often results in poor functional recovery due to the inability of host axons to re-grow long distances and reform meaningful connections with the target muscle. While surgeons can re-route local axon fascicles to the target muscle, there are no technologies to provide an exogenous source of axons without sacrificing healthy nerves. Accordingly, we have developed tissue engineered neuromuscular interfaces (TE-NMIs) as the first injectable microtissue containing motor and sensory neurons in an anatomically-inspired architecture. TE-NMIs provide axon tracts that are intended to integrate with denervated distal structures and preserve regenerative capacity during prolonged periods without host innervation. Following implant, we found that TE-NMI axons promoted Schwann cell maintenance, integrated with distal muscle, and preserved an evoked muscle response out to 20-weeks post nerve transection in absence of innervation from host axons. By repopulating the distal sheath with exogenous axons, TE-NMIs also enabled putative delayed fusion with proximal host axons, a phenomenon previously not achievable in delayed repair scenarios due to distal axon degeneration. Here, we found immediate electrophysiological recovery after fusion with proximal host axons and improved axon maturation and muscle reinnervation at 24-weeks post-transection (4-weeks following delayed nerve fusion). These findings show that TE-NMIs provide the potential to improve functional recovery following delayed nerve repair.
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Affiliation(s)
- Justin C. Burrell
- Center for Brain Injury & Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Department of Bioengineering, School of Engineering & Applied Science, University of Pennsylvania, Philadelphia, PA, USA
- Center for Neurotrauma, Neurodegeneration & Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, 19104, USA
| | - Suradip Das
- Center for Brain Injury & Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Center for Neurotrauma, Neurodegeneration & Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, 19104, USA
| | - Franco A. Laimo
- Center for Brain Injury & Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Center for Neurotrauma, Neurodegeneration & Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, 19104, USA
| | - Kritika S. Katiyar
- Center for Brain Injury & Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Axonova Medical, LLC, Philadelphia, PA, USA
| | - Kevin D. Browne
- Center for Brain Injury & Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Center for Neurotrauma, Neurodegeneration & Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, 19104, USA
| | - Robert B. Shultz
- Center for Brain Injury & Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Axonova Medical, LLC, Philadelphia, PA, USA
| | - Vishal J. Tien
- Center for Brain Injury & Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Department of Bioengineering, School of Engineering & Applied Science, University of Pennsylvania, Philadelphia, PA, USA
- Center for Neurotrauma, Neurodegeneration & Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, 19104, USA
| | - Phuong T. Vu
- Center for Brain Injury & Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Department of Bioengineering, School of Engineering & Applied Science, University of Pennsylvania, Philadelphia, PA, USA
- Center for Neurotrauma, Neurodegeneration & Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, 19104, USA
| | - Dmitriy Petrov
- Center for Brain Injury & Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Zarina S. Ali
- Center for Brain Injury & Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Joseph M. Rosen
- Dartmouth-Hitchcock Medical Center, Division of Plastic Surgery, Dartmouth College, Lebanon, NH, USA
| | - D. Kacy Cullen
- Center for Brain Injury & Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Department of Bioengineering, School of Engineering & Applied Science, University of Pennsylvania, Philadelphia, PA, USA
- Center for Neurotrauma, Neurodegeneration & Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, 19104, USA
- Axonova Medical, LLC, Philadelphia, PA, USA
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6
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Smith DH, Burrell JC, Browne KD, Katiyar KS, Ezra MI, Dutton JL, Morand JP, Struzyna LA, Laimo FA, Chen HI, Wolf JA, Kaplan HM, Rosen JM, Ledebur HC, Zager EL, Ali ZS, Cullen DK. Tissue-engineered grafts exploit axon-facilitated axon regeneration and pathway protection to enable recovery after 5-cm nerve defects in pigs. SCIENCE ADVANCES 2022; 8:eabm3291. [PMID: 36332027 PMCID: PMC9635828 DOI: 10.1126/sciadv.abm3291] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Accepted: 09/16/2022] [Indexed: 06/16/2023]
Abstract
Functional restoration following major peripheral nerve injury (PNI) is challenging, given slow axon growth rates and eventual regenerative pathway degradation in the absence of axons. We are developing tissue-engineered nerve grafts (TENGs) to simultaneously "bridge" missing nerve segments and "babysit" regenerative capacity by providing living axons to guide host axons and maintain the distal pathway. TENGs were biofabricated using porcine neurons and "stretch-grown" axon tracts. TENG neurons survived and elicited axon-facilitated axon regeneration to accelerate regrowth across both short (1 cm) and long (5 cm) segmental nerve defects in pigs. TENG axons also closely interacted with host Schwann cells to maintain proregenerative capacity. TENGs drove regeneration across 5-cm defects in both motor and mixed motor-sensory nerves, resulting in dense axon regeneration and electrophysiological recovery at levels similar to autograft repairs. This approach of accelerating axon regeneration while maintaining the pathway for long-distance regeneration may achieve recovery after currently unrepairable PNIs.
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Affiliation(s)
- Douglas H. Smith
- Center for Brain Injury and Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Axonova Medical LLC, Philadelphia, PA, USA
| | - Justin C. Burrell
- Center for Brain Injury and Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Center for Neurotrauma, Neurodegeneration and Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, USA
- Department of Bioengineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, PA, USA
| | - Kevin D. Browne
- Center for Brain Injury and Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Center for Neurotrauma, Neurodegeneration and Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, USA
| | - Kritika S. Katiyar
- Center for Brain Injury and Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Axonova Medical LLC, Philadelphia, PA, USA
- Center for Neurotrauma, Neurodegeneration and Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, USA
| | - Mindy I. Ezra
- Center for Brain Injury and Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - John L. Dutton
- Center for Brain Injury and Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Joseph P. Morand
- Center for Brain Injury and Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Laura A. Struzyna
- Center for Brain Injury and Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Center for Neurotrauma, Neurodegeneration and Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, USA
- Department of Bioengineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, PA, USA
| | - Franco A. Laimo
- Center for Brain Injury and Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Center for Neurotrauma, Neurodegeneration and Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, USA
| | - H. Isaac Chen
- Center for Brain Injury and Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Center for Neurotrauma, Neurodegeneration and Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, USA
| | - John A. Wolf
- Center for Brain Injury and Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Center for Neurotrauma, Neurodegeneration and Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, USA
| | - Hilton M. Kaplan
- New Jersey Center for Biomaterials, Rutgers University, Piscataway, NJ, USA
| | - Joseph M. Rosen
- Division of Plastic Surgery, Dartmouth Hitchcock Medical Center, Dartmouth College, Lebanon, NH, USA
| | | | - Eric L. Zager
- Center for Brain Injury and Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Zarina S. Ali
- Center for Brain Injury and Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Center for Neurotrauma, Neurodegeneration and Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, USA
| | - D. Kacy Cullen
- Center for Brain Injury and Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Axonova Medical LLC, Philadelphia, PA, USA
- Center for Neurotrauma, Neurodegeneration and Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, USA
- Department of Bioengineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, PA, USA
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Electrical Stimulation Increases Axonal Growth from Dorsal Root Ganglia Co-Cultured with Schwann Cells in Highly Aligned PLA-PPy-Au Microfiber Substrates. Int J Mol Sci 2022; 23:ijms23126362. [PMID: 35742806 PMCID: PMC9223746 DOI: 10.3390/ijms23126362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Revised: 06/01/2022] [Accepted: 06/03/2022] [Indexed: 11/30/2022] Open
Abstract
Nerve regeneration is a slow process that needs to be guided for distances greater than 5 mm. For this reason, different strategies are being studied to guide axonal growth and accelerate the axonal growth rate. In this study, we employ an electroconductive fibrillar substrate that is able to topographically guide axonal growth while accelerating the axonal growth rate when subjected to an exogenous electric field. Dorsal root ganglia were seeded in co-culture with Schwann cells on a substrate of polylactic acid microfibers coated with the electroconductive polymer polypyrrole, adding gold microfibers to increase its electrical conductivity. The substrate is capable of guiding axonal growth in a highly aligned manner and, when subjected to an electrical stimulation, an improvement in axonal growth is observed. As a result, an increase in the maximum length of the axons of 19.2% and an increase in the area occupied by the axons of 40% were obtained. In addition, an upregulation of the genes related to axon guidance, axogenesis, Schwann cells, proliferation and neurotrophins was observed for the electrically stimulated group. Therefore, our device is a good candidate for nerve regeneration therapies.
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Merolli A, Bektas C. Hoechst 33342 as a marker for imaging neurites of Dorsal Root Ganglion in vitro. J Anat 2022; 240:998-1001. [PMID: 34811747 PMCID: PMC9005665 DOI: 10.1111/joa.13599] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 11/08/2021] [Accepted: 11/16/2021] [Indexed: 01/03/2023] Open
Abstract
Fluorescent markers, generally targeting neurotubules, are used to visualize the radiating crown of growing neurites that is produced by dorsal root ganglion cells in vitro. Hoechst 33342 (2'-[4-ethoxyphenyl]-5-[4-methyl-1-piperazinyl]-2,5'-bi-1H-benzimidazole trihydrochloride trihydrate) is a widely used fluorescent DNA marker that stain both live and fixed nuclei. We have recently found that H33342 can visualize the neurites of DRG too, but only when they are fixed in formalin. Images have a good signal-to-noise ratio. We noticed that besides H33342 being a specific marker for DNA, it also stains the transmembrane P-glycoprotein (P-gp) which is involved in the active pump-out of alien molecules from the cytoplasm; so, H33342 remains associated with P-gp after fixation. P-gp is quite ubiquitous in healthy cells and, notably, P-gp has been detected in DRG of several species as well as in human DRG. The use of H33342 as a staining for neurites of DRG in fixed samples could have a practical value due to its widespread use and its better affordability compared to other fluorescent markers for neurites.
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Affiliation(s)
- Antonio Merolli
- Department of Physics and AstronomyHelium‐ion Microscopy FacilityRutgers, The State University of New JerseyPiscatawayNew JerseyUSA
| | - Cemile Bektas
- Department of Chemistry and Chemical BiologyRutgers, The State University of New JerseyPiscatawayNew JerseyUSA
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9
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Roca FG, Santos LG, Roig MM, Medina LM, Martínez-Ramos C, Pradas MM. Novel Tissue-Engineered Multimodular Hyaluronic Acid-Polylactic Acid Conduits for the Regeneration of Sciatic Nerve Defect. Biomedicines 2022; 10:biomedicines10050963. [PMID: 35625700 PMCID: PMC9138968 DOI: 10.3390/biomedicines10050963] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Revised: 04/14/2022] [Accepted: 04/18/2022] [Indexed: 02/01/2023] Open
Abstract
The gold standard for the treatment of peripheral nerve injuries, the autograft, presents several drawbacks, and engineered constructs are currently suitable only for short gaps or small diameter nerves. Here, we study a novel tissue-engineered multimodular nerve guidance conduit for the treatment of large nerve damages based in a polylactic acid (PLA) microfibrillar structure inserted inside several co-linear hyaluronic acid (HA) conduits. The highly aligned PLA microfibers provide a topographical cue that guides axonal growth, and the HA conduits play the role of an epineurium and retain the pre-seeded auxiliary cells. The multimodular design increases the flexibility of the device. Its performance for the regeneration of a critical-size (15 mm) rabbit sciatic nerve defect was studied and, after six months, very good nerve regeneration was observed. The multimodular approach contributed to a better vascularization through the micrometrical gaps between HA conduits, and the pre-seeded Schwann cells increased axonal growth. Six months after surgery, a cross-sectional available area occupied by myelinated nerve fibers above 65% at the central and distal portions was obtained when the multimodular device with pre-seeded Schwann cells was employed. The results validate the multi-module approach for the regeneration of large nerve defects and open new possibilities for surgical solutions in this field.
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Affiliation(s)
- Fernando Gisbert Roca
- Center for Biomaterials and Tissue Engineering, Universitat Politècnica de València, 46022 Valencia, Spain; (F.G.R.); (L.G.S.); (C.M.-R.)
| | - Luis Gil Santos
- Center for Biomaterials and Tissue Engineering, Universitat Politècnica de València, 46022 Valencia, Spain; (F.G.R.); (L.G.S.); (C.M.-R.)
| | - Manuel Mata Roig
- Department of Pathology, Faculty of Medicine and Dentistry, Universitat de València, 46010 Valencia, Spain; (M.M.R.); (L.M.M.)
| | - Lara Milian Medina
- Department of Pathology, Faculty of Medicine and Dentistry, Universitat de València, 46010 Valencia, Spain; (M.M.R.); (L.M.M.)
| | - Cristina Martínez-Ramos
- Center for Biomaterials and Tissue Engineering, Universitat Politècnica de València, 46022 Valencia, Spain; (F.G.R.); (L.G.S.); (C.M.-R.)
- Unitat Predepartamental de Medicina, Universitat Jaume I, 12071 Castellón de la Plana, Spain
| | - Manuel Monleón Pradas
- Center for Biomaterials and Tissue Engineering, Universitat Politècnica de València, 46022 Valencia, Spain; (F.G.R.); (L.G.S.); (C.M.-R.)
- Biomedical Research Networking Center in Bioengineering Biomaterials and Nanomedicine (CIBER-BBN), 28029 Madrid, Spain
- Correspondence: ; Tel.: +34-963-877000
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Liu G, Ma M, Meng H, Liu J, Zheng Y, Peng J, Wei S, Sun Y, Wang Y, Xie Y, Li J. In-situ self-assembly of bacterial cellulose/poly(3,4-ethylenedioxythiophene)-sulfonated nanofibers for peripheral nerve repair. Carbohydr Polym 2022; 281:119044. [DOI: 10.1016/j.carbpol.2021.119044] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Revised: 12/19/2021] [Accepted: 12/22/2021] [Indexed: 12/21/2022]
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11
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Podsednik A, Cabrejo R, Rosen J. Adipose Tissue Uses in Peripheral Nerve Surgery. Int J Mol Sci 2022; 23:ijms23020644. [PMID: 35054833 PMCID: PMC8776017 DOI: 10.3390/ijms23020644] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 12/30/2021] [Accepted: 01/02/2022] [Indexed: 12/15/2022] Open
Abstract
Currently, many different techniques exist for the surgical repair of peripheral nerves. The degree of injury dictates the repair and, depending on the defect or injury of the peripheral nerve, plastic surgeons can perform nerve repairs, grafts, and transfers. All the previously listed techniques are routinely performed in human patients, but a novel addition to these peripheral nerve surgeries involves concomitant fat grafting to the repair site at the time of surgery. Fat grafting provides adipose-derived stem cells to the injury site. Though fat grafting is performed as an adjunct to some peripheral nerve surgeries, there is no clear evidence as to which procedures have improved outcomes resultant from concomitant fat grafting. This review explores the evidence presented in various animal studies regarding outcomes of fat grafting at the time of various types of peripheral nerve surgery.
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Affiliation(s)
- Allison Podsednik
- The University of Texas Rio Grande Valley School of Medicine, Edinburg, TX 78541, USA;
| | - Raysa Cabrejo
- Section of Plastic Surgery, Department of Surgery, Dartmouth-Hitchcock Medical Center, Lebanon, NH 03766, USA;
| | - Joseph Rosen
- Section of Plastic Surgery, Department of Surgery, Dartmouth-Hitchcock Medical Center, Lebanon, NH 03766, USA;
- Correspondence:
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12
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Lu P, Wang G, Qian T, Cai X, Zhang P, Li M, Shen Y, Xue C, Wang H. The balanced microenvironment regulated by the degradants of appropriate PLGA scaffolds and chitosan conduit promotes peripheral nerve regeneration. Mater Today Bio 2021; 12:100158. [PMID: 34841240 PMCID: PMC8605345 DOI: 10.1016/j.mtbio.2021.100158] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Revised: 11/10/2021] [Accepted: 11/13/2021] [Indexed: 12/19/2022] Open
Abstract
Tissue-engineered nerve grafts (TENGs) are the most promising way for repairing long-distance peripheral nerve defects. Chitosan and poly (lactic-co-glycolic acid) (PLGA) scaffolds are considered as the promising materials in the pharmaceutical and biomedical fields especially in the field of tissue engineering. To further clarify the effects of a chitosan conduit inserted with various quantity of poly (lactic-co-glycolic acid) (PLGA) scaffolds, and their degrades on the peripheral nerve regeneration, the chitosan nerve conduit inserted with different amounts of PLGA scaffolds were used to repair rat sciatic nerve defects. The peripheral nerve regeneration at the different time points was dynamically and comprehensively evaluated. Moreover, the influence of different amounts of PLGA scaffolds on the regeneration microenvironment including inflammatory response and cell state were also revealed. The modest abundance of PLGA is more instrumental to the success of nerve regeneration, which is demonstrated in terms of the structure of the regenerated nerve, reinnervation of the target muscle, nerve impulse conduction, and overall function. The PLGA scaffolds aid the migration and maturation of Schwann cells. Furthermore, the PLGA and chitosan degradation products in a correct ratio neutralize, reducing the inflammatory response and enhancing the regeneration microenvironment. The balanced microenvironment regulated by the degradants of appropriate PLGA scaffolds and chitosan conduit promotes peripheral nerve regeneration. The findings represent a further step towards programming TENGs construction, applying polyester materials in regenerative medicine, and understanding the neural regeneration microenvironment. Guide scaffolds are necessary for construction of TENGs to benefeat Schwann cell migration and maturation. A large number of acid degradation products of PLGA scaffolds adversely affect cell proliferation, migration and apoptosis. Appropriate amount of PLGA scaffolds balance positive cell guidance and negative degradation inflammation. Dosage of PLGA and its combination with complementary biomaterials are key factors that affect regeneration effects.
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Key Words
- ANOVA, one-way analysis of variance
- CCK8, Cell Counting Kit-8
- CMAPs, compound muscle action potentials
- DAPI, 4’ 6-diamidino-2-phenylindole
- DMEM, Dulbecco’s modified eagle medium
- FBS, fetal bovine serum
- HE, hematoxylin-eosin
- Inflammation
- NC, negative control
- NS, normal saline
- OD, optical density
- PGA, poly (glycolic acid)
- PLA, poly (lactic acid)
- PLGA
- PLGA, poly (lactic-co-glycolic acid)
- Regeneration microenvironment
- SCs, Schwann cells
- SD, Sprague-Dawley
- SD, standard deviation
- SFI, sciatic nerve function index
- Schwann cells
- TENG, tissue-engineered nerve graft
- TUNEL, terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling
- α-BGT, α-bungarotoxin
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Affiliation(s)
- Panjian Lu
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-innovation Center of Neuroregeneration, NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology Products, Nantong University, Nantong, China
| | - Gang Wang
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-innovation Center of Neuroregeneration, NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology Products, Nantong University, Nantong, China
| | - Tianmei Qian
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-innovation Center of Neuroregeneration, NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology Products, Nantong University, Nantong, China
| | - Xiaodong Cai
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-innovation Center of Neuroregeneration, NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology Products, Nantong University, Nantong, China
| | - Ping Zhang
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-innovation Center of Neuroregeneration, NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology Products, Nantong University, Nantong, China
| | - Meiyuan Li
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-innovation Center of Neuroregeneration, NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology Products, Nantong University, Nantong, China
| | - Yinying Shen
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-innovation Center of Neuroregeneration, NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology Products, Nantong University, Nantong, China
| | - Chengbin Xue
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-innovation Center of Neuroregeneration, NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology Products, Nantong University, Nantong, China.,Jiangsu Clinical Medicine Center of Tissue Engineering and Nerve Injury Repair, Research Center of Clinical Medicine, Affiliated Hospital of Nantong University, Nantong, China
| | - Hongkui Wang
- Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education, Co-innovation Center of Neuroregeneration, NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology Products, Nantong University, Nantong, China
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13
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Katiyar KS, Burrell JC, Laimo FA, Browne KD, Bianchi JR, Walters A, Ayares DL, Smith DH, Ali ZS, Ledebur HC, Cullen DK. Biomanufacturing of Axon-Based Tissue Engineered Nerve Grafts Using Porcine GalSafe Neurons. Tissue Eng Part A 2021; 27:1305-1320. [PMID: 33514288 PMCID: PMC8610031 DOI: 10.1089/ten.tea.2020.0303] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Accepted: 01/11/2021] [Indexed: 12/14/2022] Open
Abstract
Existing strategies for repair of major peripheral nerve injury (PNI) are inefficient at promoting axon regeneration and functional recovery and are generally ineffective for nerve lesions >5 cm. To address this need, we have previously developed tissue engineered nerve grafts (TENGs) through the process of axon stretch growth. TENGs consist of living, centimeter-scale, aligned axon tracts that accelerate axon regeneration at rates equivalent to the gold standard autograft in small and large animal models of PNI, by providing a newfound mechanism-of-action referred to as axon-facilitated axon regeneration (AFAR). To enable clinical-grade biomanufacturing of TENGs, a suitable cell source that is hypoimmunogenic, exhibits low batch-to-batch variability, and able to tolerate axon stretch growth must be utilized. To fulfill these requirements, a genetically engineered, FDA-approved, xenogeneic cell source, GalSafe® neurons, produced by Revivicor, Inc., have been selected to advance TENG biofabrication for eventual clinical use. To this end, sensory and motor neurons were harvested from genetically engineered GalSafe day 40 swine embryos, cultured in custom mechanobioreactors, and axon tracts were successfully stretch-grown to 5 cm within 25 days. Importantly, both sensory and motor GalSafe neurons were observed to tolerate established axon stretch growth regimes of ≥1 mm/day to produce continuous, healthy axon tracts spanning 1, 3, or 5 cm. Once stretch-grown, 1 cm GalSafe TENGs were transplanted into a 1 cm lesion in the sciatic nerve of athymic rats. Regeneration was assessed through histological measures at the terminal time point of 2 and 8 weeks. Neurons from GalSafe TENGs survived and elicited AFAR as observed when using wild-type TENGs. At 8 weeks postrepair, myelinated regenerated axons were observed in the nerve section distal to the injury site, confirming axon regeneration across the lesion. These experiments are the first to demonstrate successful harvest and axon stretch growth of GalSafe neurons for use as starting biomass for bioengineered nerve grafts as well as initial safety and efficacy in an established preclinical model-important steps for the advancement of clinical-grade TENGs for future regulatory testing and eventual clinical trials. Impact statement Biofabrication of tissue engineered medical products requires several steps, one of which is choosing a suitable starting biomass. To this end, we have shown that the clinical-grade, genetically engineered biomass-GalSafe® neurons-is a viable option for biomanufacturing of our tissue engineered nerve grafts (TENGs) to promote regeneration following major peripheral nerve injury. Importantly, this is a first step in clinical-grade TENG biofabrication, proving that GalSafe TENGs recapitulate the mechanism of axon-facilitated axon regeneration seen previously with research-grade TENGs.
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Affiliation(s)
- Kritika S. Katiyar
- Axonova Medical, LLC, Philadelphia, Pennsylvania, USA
- Center for Brain Injury & Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Center for Neurotrauma, Neurodegeneration & Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, Pennsylvania, USA
| | - Justin C. Burrell
- Center for Brain Injury & Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Center for Neurotrauma, Neurodegeneration & Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, Pennsylvania, USA
| | - Franco A. Laimo
- Center for Brain Injury & Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Center for Neurotrauma, Neurodegeneration & Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, Pennsylvania, USA
| | - Kevin D. Browne
- Center for Brain Injury & Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Center for Neurotrauma, Neurodegeneration & Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, Pennsylvania, USA
| | | | | | | | - Douglas H. Smith
- Axonova Medical, LLC, Philadelphia, Pennsylvania, USA
- Center for Brain Injury & Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Zarina S. Ali
- Center for Brain Injury & Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Center for Neurotrauma, Neurodegeneration & Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, Pennsylvania, USA
| | - Harry C. Ledebur
- Axonova Medical, LLC, Philadelphia, Pennsylvania, USA
- Battelle Memorial Institute, Columbus, Ohio, USA
| | - D. Kacy Cullen
- Axonova Medical, LLC, Philadelphia, Pennsylvania, USA
- Center for Brain Injury & Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Center for Neurotrauma, Neurodegeneration & Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, Pennsylvania, USA
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14
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Sullivan PZ, AlBayar A, Burrell JC, Browne KD, Arena J, Johnson V, Smith DH, Cullen DK, Ozturk AK. Implantation of Engineered Axon Tracts to Bridge Spinal Cord Injury Beyond the Glial Scar in Rats. Tissue Eng Part A 2021; 27:1264-1274. [PMID: 33430694 DOI: 10.1089/ten.tea.2020.0233] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Regeneration after spinal cord injury (SCI) is limited by the presence of a glial scar and inhibitory cell signaling pathways that favor scar formation over regrowth of endogenous neurons. Tissue engineering techniques, including the use of allografted neural networks, have shown promise for nervous system repair in prior studies. Through the use of a minimally invasive injury model in rats, we describe the implantation of micro-tissue engineered neural networks (micro-TENNs) across a region of SCI, spanning the glial scar to promote axonal regeneration. Forty-three female Sprague-Dawley rats were included in this study. Micro-TENNs were preformed in vitro before implant, and comprised rat sensory dorsal root ganglion (DRG) neurons projecting long bundled axonal tracts within the lumen of a biocompatible hydrogel columnar encasement (1.2 cm long; 701 μm outer diameter × 300 μm inner diameter). Animals were injured using a 2F embolectomy catheter inflated within the epidural space. After a 2-week recovery period, micro-TENNs were stereotactically implanted across the injury. Animals were euthanized at 1 week and 1 month after implantation, and the tissue was interrogated for the survival of graft DRG neurons and outgrowth of axons. No intraoperative deaths were noted with implantation of the micro-TENNs to span the injury cavity. Graft DRG axons were found to survive at 1 week postimplant within the hydrogel encasement. Graft-derived axonal outgrowth was observed within the spinal cord up to 4.5 mm from the implant site at 1 month postinjury. Limited astroglial response was noted within the host, suggesting minimal trauma and scar formation in response to the graft. Micro-TENN sensory neurons survive and extend axons into the host spinal cord following a minimally invasive SCI in rats. This work serves as the foundation for future studies investigating the use of micro-TENNs as a living bridge to promote recovery following SCI. Impact statement As spinal cord injury pathology develops, the establishment of a glial scar puts an end to the hope of regeneration and recovery from the consequent neurological deficits. Therefore, growing attention is given to bioengineered scaffolds that can bridge the lesions bordered by this scar tissue. The utilization of longitudinally aligned preformed neural networks-referred to as micro-tissue engineered neural networks (TENNs)-presents a promising opportunity to provide a multipurpose bridging strategy that may take advantage of several potential mechanisms of host regeneration. In addition to providing physical support for regenerating spinal cord axons, micro-TENNs may serve as a functional "cable" that restores lost connections within the spinal cord.
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Affiliation(s)
- Patricia Zadnik Sullivan
- Department of Neurosurgery, Center for Brain Injury & Repair, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Ahmed AlBayar
- Department of Neurosurgery, Center for Brain Injury & Repair, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Justin C Burrell
- Department of Neurosurgery, Center for Brain Injury & Repair, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA.,Department of Bioengineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, Pennsylvania, USA.,Center for Neurotrauma, Neurodegeneration & Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, Pennsylvania, USA
| | - Kevin D Browne
- Department of Neurosurgery, Center for Brain Injury & Repair, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA.,Center for Neurotrauma, Neurodegeneration & Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, Pennsylvania, USA
| | - John Arena
- Department of Neurosurgery, Center for Brain Injury & Repair, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Victoria Johnson
- Department of Neurosurgery, Center for Brain Injury & Repair, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Douglas H Smith
- Department of Neurosurgery, Center for Brain Injury & Repair, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - D Kacy Cullen
- Department of Neurosurgery, Center for Brain Injury & Repair, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA.,Department of Bioengineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, Pennsylvania, USA.,Center for Neurotrauma, Neurodegeneration & Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, Pennsylvania, USA
| | - Ali K Ozturk
- Department of Neurosurgery, Center for Brain Injury & Repair, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
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15
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Shultz RB, Katiyar KS, Laimo FA, Burrell JC, Browne KD, Ali ZS, Cullen DK. Biopreservation of living tissue engineered nerve grafts. J Tissue Eng 2021; 12:20417314211032488. [PMID: 34394908 PMCID: PMC8361542 DOI: 10.1177/20417314211032488] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2021] [Accepted: 06/24/2021] [Indexed: 01/22/2023] Open
Abstract
Tissue engineered nerve grafts (TENGs) built from living neurons and aligned axon tracts offer a revolutionary new approach as "living scaffolds" to bridge major peripheral nerve defects. Clinical application, however, necessitates sufficient shelf-life to allow for shipping from manufacturing facility to clinic as well as storage until use. Here, hypothermic storage in commercially available hibernation media is explored as a potential biopreservation strategy for TENGs. After up to 28 days of refrigeration at 4℃, TENGs maintain viability and structure in vitro. Following transplantation into 1 cm rat sciatic defects, biopreserved TENGs routinely survive and persist for at least 2 weeks and recapitulate pro-regenerative mechanisms of fresh TENGs, including the ability to recruit regenerating host tissue into the graft and extend neurites beyond the margins of the graft. The protocols and timelines established here serve as important foundational work for the manufacturing, storage, and translation of other neuron-based tissue engineered therapeutics.
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Affiliation(s)
- Robert B Shultz
- Center for Neurotrauma, Neurodegeneration & Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, USA
- Center for Brain Injury and Repair, Department of Neurosurgery, University of Pennsylvania, Philadelphia, PA, USA
- Department of Chemistry and Chemical Biology, School of Arts and Sciences, Rutgers University, Piscataway, NJ, USA
- Axonova Medical, LLC, Philadelphia, PA, USA
| | - Kritika S Katiyar
- Center for Neurotrauma, Neurodegeneration & Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, USA
- Center for Brain Injury and Repair, Department of Neurosurgery, University of Pennsylvania, Philadelphia, PA, USA
- Axonova Medical, LLC, Philadelphia, PA, USA
| | - Franco A Laimo
- Center for Neurotrauma, Neurodegeneration & Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, USA
- Center for Brain Injury and Repair, Department of Neurosurgery, University of Pennsylvania, Philadelphia, PA, USA
| | - Justin C Burrell
- Center for Neurotrauma, Neurodegeneration & Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, USA
- Center for Brain Injury and Repair, Department of Neurosurgery, University of Pennsylvania, Philadelphia, PA, USA
- Department of Bioengineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, PA, USA
| | - Kevin D Browne
- Center for Neurotrauma, Neurodegeneration & Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, USA
- Center for Brain Injury and Repair, Department of Neurosurgery, University of Pennsylvania, Philadelphia, PA, USA
| | - Zarina S Ali
- Center for Brain Injury and Repair, Department of Neurosurgery, University of Pennsylvania, Philadelphia, PA, USA
- Penn Nerve Center, University of Pennsylvania, Philadelphia, PA, USA
| | - Daniel K Cullen
- Center for Neurotrauma, Neurodegeneration & Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, USA
- Center for Brain Injury and Repair, Department of Neurosurgery, University of Pennsylvania, Philadelphia, PA, USA
- Department of Bioengineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, PA, USA
- Axonova Medical, LLC, Philadelphia, PA, USA
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16
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Maggiore JC, Burrell JC, Browne KD, Katiyar KS, Laimo FA, Ali ZS, Kaplan HM, Rosen JM, Cullen DK. Tissue engineered axon-based "living scaffolds" promote survival of spinal cord motor neurons following peripheral nerve repair. J Tissue Eng Regen Med 2020; 14:1892-1907. [PMID: 33049797 DOI: 10.1002/term.3145] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Revised: 09/11/2020] [Accepted: 10/02/2020] [Indexed: 12/19/2022]
Abstract
Peripheral nerve injury (PNI) impacts millions annually, often leaving debilitated patients with minimal repair options to improve functional recovery. Our group has previously developed tissue engineered nerve grafts (TENGs) featuring long, aligned axonal tracts from dorsal root ganglia (DRG) neurons that are fabricated in custom bioreactors using the process of axon "stretch-growth." We have shown that TENGs effectively serve as "living scaffolds" to promote regeneration across segmental nerve defects by exploiting the newfound mechanism of axon-facilitated axon regeneration, or "AFAR," by simultaneously providing haptic and neurotrophic support. To extend this work, the current study investigated the efficacy of living versus nonliving regenerative scaffolds in preserving host sensory and motor neuronal health following nerve repair. Rats were assigned across five groups: naïve, or repair using autograft, nerve guidance tube (NGT) with collagen, NGT + non-aligned DRG populations in collagen, or TENGs. We found that TENG repairs yielded equivalent regenerative capacity as autograft repairs based on preserved health of host spinal cord motor neurons and acute axonal regeneration, whereas NGT repairs or DRG neurons within an NGT exhibited reduced motor neuron preservation and diminished regenerative capacity. These acute regenerative benefits ultimately resulted in enhanced levels of functional recovery in animals receiving TENGs, at levels matching those attained by autografts. Our findings indicate that TENGs may preserve host spinal cord motor neuron health and regenerative capacity without sacrificing an otherwise uninjured nerve (as in the case of the autograft) and therefore represent a promising alternative strategy for neurosurgical repair following PNI.
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Affiliation(s)
- Joseph C Maggiore
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA.,Department of Neurosurgery, University of Pennsylvania, Philadelphia, PA, USA.,Center for Neurotrauma, Neurodegeneration & Restoration, CMC VA Medical Center, Philadelphia, PA, USA
| | - Justin C Burrell
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA.,Department of Neurosurgery, University of Pennsylvania, Philadelphia, PA, USA.,Center for Neurotrauma, Neurodegeneration & Restoration, CMC VA Medical Center, Philadelphia, PA, USA
| | - Kevin D Browne
- Department of Neurosurgery, University of Pennsylvania, Philadelphia, PA, USA.,Center for Neurotrauma, Neurodegeneration & Restoration, CMC VA Medical Center, Philadelphia, PA, USA
| | - Kritika S Katiyar
- Department of Neurosurgery, University of Pennsylvania, Philadelphia, PA, USA.,Center for Neurotrauma, Neurodegeneration & Restoration, CMC VA Medical Center, Philadelphia, PA, USA.,Axonova Medical LLC, Philadelphia, PA, USA
| | - Franco A Laimo
- Department of Neurosurgery, University of Pennsylvania, Philadelphia, PA, USA.,Center for Neurotrauma, Neurodegeneration & Restoration, CMC VA Medical Center, Philadelphia, PA, USA
| | - Zarina S Ali
- Department of Neurosurgery, University of Pennsylvania, Philadelphia, PA, USA
| | - Hilton M Kaplan
- New Jersey Center for Biomaterials, Rutgers University, New Brunswick, NJ, USA
| | - Joseph M Rosen
- Dartmouth-Hitchcock Medical Center, Division of Plastic Surgery, Dartmouth College, Lebanon, NH, USA
| | - D Kacy Cullen
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA.,Department of Neurosurgery, University of Pennsylvania, Philadelphia, PA, USA.,Center for Neurotrauma, Neurodegeneration & Restoration, CMC VA Medical Center, Philadelphia, PA, USA.,Axonova Medical LLC, Philadelphia, PA, USA
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17
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Panzer KV, Burrell JC, Helm KVT, Purvis EM, Zhang Q, Le AD, O’Donnell JC, Cullen DK. Tissue Engineered Bands of Büngner for Accelerated Motor and Sensory Axonal Outgrowth. Front Bioeng Biotechnol 2020; 8:580654. [PMID: 33330416 PMCID: PMC7714719 DOI: 10.3389/fbioe.2020.580654] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Accepted: 09/28/2020] [Indexed: 12/15/2022] Open
Abstract
Following peripheral nerve injury comprising a segmental defect, the extent of axon regeneration decreases precipitously with increasing gap length. Schwann cells play a key role in driving axon re-growth by forming aligned tubular guidance structures called bands of Büngner, which readily occurs in distal nerve segments as well as within autografts - currently the most reliable clinically-available bridging strategy. However, host Schwann cells generally fail to infiltrate large-gap acellular scaffolds, resulting in markedly inferior outcomes and motivating the development of next-generation bridging strategies capable of fully exploiting the inherent pro-regenerative capability of Schwann cells. We sought to create preformed, implantable Schwann cell-laden microtissue that emulates the anisotropic structure and function of naturally-occurring bands of Büngner. Accordingly, we developed a biofabrication scheme leveraging biomaterial-induced self-assembly of dissociated rat primary Schwann cells into dense, fiber-like three-dimensional bundles of Schwann cells and extracellular matrix within hydrogel micro-columns. This engineered microtissue was found to be biomimetic of morphological and phenotypic features of endogenous bands of Büngner, and also demonstrated 8 and 2× faster rates of axonal extension in vitro from primary rat spinal motor neurons and dorsal root ganglion sensory neurons, respectively, compared to 3D matrix-only controls or planar Schwann cells. To our knowledge, this is the first report of accelerated motor axon outgrowth using aligned Schwann cell constructs. For translational considerations, this microtissue was also fabricated using human gingiva-derived Schwann cells as an easily accessible autologous cell source. These results demonstrate the first tissue engineered bands of Büngner (TE-BoBs) comprised of dense three-dimensional bundles of longitudinally aligned Schwann cells that are readily scalable as implantable grafts to accelerate axon regeneration across long segmental nerve defects.
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Affiliation(s)
- Kate V. Panzer
- Center for Brain Injury and Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
- Center for Neurotrauma, Neurodegeneration and Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, United States
- Department of Bioengineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, PA, United States
| | - Justin C. Burrell
- Center for Brain Injury and Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
- Center for Neurotrauma, Neurodegeneration and Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, United States
- Department of Bioengineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, PA, United States
| | - Kaila V. T. Helm
- Center for Brain Injury and Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
- Center for Neurotrauma, Neurodegeneration and Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, United States
| | - Erin M. Purvis
- Center for Brain Injury and Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
- Center for Neurotrauma, Neurodegeneration and Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, United States
- Department of Neuroscience, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Qunzhou Zhang
- Department of Oral and Maxillofacial Surgery, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, United States
- Department of Oral and Maxillofacial Surgery, Penn Medicine Hospital of University of Pennsylvania, Philadelphia, PA, United States
| | - Anh D. Le
- Department of Oral and Maxillofacial Surgery, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, United States
- Department of Oral and Maxillofacial Surgery, Penn Medicine Hospital of University of Pennsylvania, Philadelphia, PA, United States
| | - John C. O’Donnell
- Center for Brain Injury and Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
- Center for Neurotrauma, Neurodegeneration and Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, United States
| | - D. Kacy Cullen
- Center for Brain Injury and Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
- Center for Neurotrauma, Neurodegeneration and Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA, United States
- Department of Bioengineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, PA, United States
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18
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Burrell JC, Bhatnagar D, Brown DP, Murthy NS, Dutton J, Browne KD, Laimo FA, Ali ZS, Rosen JM, Kaplan HM, Kohn J, Cullen DK. Tyrosine-derived polycarbonate nerve guidance tubes elicit proregenerative extracellular matrix deposition when used to bridge segmental nerve defects in swine. J Biomed Mater Res A 2020; 109:1183-1195. [PMID: 32985789 DOI: 10.1002/jbm.a.37110] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Revised: 09/23/2020] [Accepted: 09/26/2020] [Indexed: 12/15/2022]
Abstract
Promising biomaterials should be tested in appropriate large animal models that recapitulate human inflammatory and regenerative responses. Previous studies have shown tyrosine-derived polycarbonates (TyrPC) are versatile biomaterials with a wide range of applications across multiple disciplines. The library of TyrPC has been well studied and consists of thousands of polymer compositions with tunable mechanical characteristics and degradation and resorption rates that are useful for nerve guidance tubes (NGTs). NGTs made of different TyrPCs have been used in segmental nerve defect models in small animals. The current study is an extension of this work and evaluates NGTs made using two different TyrPC compositions in a 1 cm porcine peripheral nerve repair model. We first evaluated a nondegradable TyrPC formulation, demonstrating proof-of-concept chronic regenerative efficacy up to 6 months with similar nerve/muscle electrophysiology and morphometry to the autograft repair control. Next, we characterized the acute regenerative response using a degradable TyrPC formulation. After 2 weeks in vivo, TyrPC NGT promoted greater deposition of pro-regenerative extracellular matrix (ECM) constituents (in particular collagen I, collagen III, collagen IV, laminin, and fibronectin) compared to commercially available collagen-based NGTs. This corresponded with dense Schwann cell infiltration and axon extension across the lumen. These findings confirmed results reported previously in a mouse model and reveal that TyrPC NGTs were well tolerated in swine and facilitated host axon regeneration and Schwann cell infiltration in the acute phase across segmental defects - likely by eliciting a favorable neurotrophic ECM milieu. This regenerative response ultimately can contribute to functional recovery.
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Affiliation(s)
- Justin C Burrell
- Center for Brain Injury & Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA.,Center for Neurotrauma, Neurodegeneration & Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, Pennsylvania, USA.,Department of Bioengineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Divya Bhatnagar
- New Jersey Center for Biomaterials, Rutgers University, New Brunswick, New Jersey, USA
| | - Dan P Brown
- Center for Brain Injury & Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA.,Center for Neurotrauma, Neurodegeneration & Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, Pennsylvania, USA
| | - N Sanjeeva Murthy
- New Jersey Center for Biomaterials, Rutgers University, New Brunswick, New Jersey, USA
| | - John Dutton
- Center for Brain Injury & Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Kevin D Browne
- Center for Brain Injury & Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA.,Center for Neurotrauma, Neurodegeneration & Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, Pennsylvania, USA
| | - Franco A Laimo
- Center for Brain Injury & Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA.,Center for Neurotrauma, Neurodegeneration & Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, Pennsylvania, USA
| | - Zarina S Ali
- Center for Brain Injury & Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Joseph M Rosen
- Dartmouth-Hitchcock Medical Center, Division of Plastic Surgery, Dartmouth College, Lebanon, New Hampshire, USA
| | - Hilton M Kaplan
- New Jersey Center for Biomaterials, Rutgers University, New Brunswick, New Jersey, USA
| | - Joachim Kohn
- New Jersey Center for Biomaterials, Rutgers University, New Brunswick, New Jersey, USA
| | - D Kacy Cullen
- Center for Brain Injury & Repair, Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA.,Center for Neurotrauma, Neurodegeneration & Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, Pennsylvania, USA.,Department of Bioengineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, Pennsylvania, USA
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Kim E, Jeon S, An HK, Kianpour M, Yu SW, Kim JY, Rah JC, Choi H. A magnetically actuated microrobot for targeted neural cell delivery and selective connection of neural networks. SCIENCE ADVANCES 2020; 6:eabb5696. [PMID: 32978164 PMCID: PMC7518876 DOI: 10.1126/sciadv.abb5696] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Accepted: 08/10/2020] [Indexed: 05/02/2023]
Abstract
There has been a great deal of interest in the development of technologies for actively manipulating neural networks in vitro, providing natural but simplified environments in a highly reproducible manner in which to study brain function and related diseases. Platforms for these in vitro neural networks require precise and selective neural connections at the target location, with minimal external influences, and measurement of neural activity to determine how neurons communicate. Here, we report a neuron-loaded microrobot for selective connection of neural networks via precise delivery to a gap between two neural clusters by an external magnetic field. In addition, the extracellular action potential was propagated from one cluster to the other through the neurons on the microrobot. The proposed technique shows the potential for use in experiments to understand how neurons communicate in the neural network by actively connecting neural clusters.
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Affiliation(s)
- Eunhee Kim
- Department of Robotics Engineering, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu 42988, South Korea
- DGIST-ETH Microrobot Research Center, DGIST, Daegu 42988, South Korea
| | - Sungwoong Jeon
- Department of Robotics Engineering, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu 42988, South Korea
- DGIST-ETH Microrobot Research Center, DGIST, Daegu 42988, South Korea
| | - Hyun-Kyu An
- Department of Brain and Cognitive Sciences, DGIST, Daegu 42988, South Korea
| | | | - Seong-Woon Yu
- Department of Brain and Cognitive Sciences, DGIST, Daegu 42988, South Korea
| | - Jin-Young Kim
- Department of Robotics Engineering, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu 42988, South Korea.
- DGIST-ETH Microrobot Research Center, DGIST, Daegu 42988, South Korea
| | - Jong-Cheol Rah
- Department of Brain and Cognitive Sciences, DGIST, Daegu 42988, South Korea
- Korea Brain Research Institute, Daegu 42988, South Korea
| | - Hongsoo Choi
- Department of Robotics Engineering, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu 42988, South Korea.
- DGIST-ETH Microrobot Research Center, DGIST, Daegu 42988, South Korea
- Robotics Research Center, DGIST, Daegu 42988, South Korea
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