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Vecchi JT, Claussen AD, Hansen MR. Decreasing the physical gap in the neural-electrode interface and related concepts to improve cochlear implant performance. Front Neurosci 2024; 18:1425226. [PMID: 39114486 PMCID: PMC11303154 DOI: 10.3389/fnins.2024.1425226] [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: 04/29/2024] [Accepted: 07/11/2024] [Indexed: 08/10/2024] Open
Abstract
Cochlear implants (CI) represent incredible devices that restore hearing perception for those with moderate to profound sensorineural hearing loss. However, the ability of a CI to restore complex auditory function is limited by the number of perceptually independent spectral channels provided. A major contributor to this limitation is the physical gap between the CI electrodes and the target spiral ganglion neurons (SGNs). In order for CI electrodes to stimulate SGNs more precisely, and thus better approximate natural hearing, new methodologies need to be developed to decrease this gap, (i.e., transitioning CIs from a far-field to near-field device). In this review, strategies aimed at improving the neural-electrode interface are discussed in terms of the magnitude of impact they could have and the work needed to implement them. Ongoing research suggests current clinical efforts to limit the CI-related immune response holds great potential for improving device performance. This could eradicate the dense, fibrous capsule surrounding the electrode and enhance preservation of natural cochlear architecture, including SGNs. In the long term, however, optimized future devices will likely need to induce and guide the outgrowth of the peripheral process of SGNs to be in closer proximity to the CI electrode in order to better approximate natural hearing. This research is in its infancy; it remains to be seen which strategies (surface patterning, small molecule release, hydrogel coating, etc.) will be enable this approach. Additionally, these efforts aimed at optimizing CI function will likely translate to other neural prostheses, which face similar issues.
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Affiliation(s)
- Joseph T. Vecchi
- Department of Molecular Physiology and Biophysics, Carver College of Medicine, Iowa City, IA, United States
- Department of Otolaryngology Head-Neck Surgery, Carver College of Medicine, Iowa City, IA, United States
| | - Alexander D. Claussen
- Department of Otolaryngology Head-Neck Surgery, Carver College of Medicine, Iowa City, IA, United States
| | - Marlan R. Hansen
- Department of Molecular Physiology and Biophysics, Carver College of Medicine, Iowa City, IA, United States
- Department of Otolaryngology Head-Neck Surgery, Carver College of Medicine, Iowa City, IA, United States
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2
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Vecchi JT, Rhomberg M, Guymon CA, Hansen MR. The geometry of photopolymerized topography influences neurite pathfinding by directing growth cone morphology and migration. J Neural Eng 2024; 21:026027. [PMID: 38547528 PMCID: PMC10993768 DOI: 10.1088/1741-2552/ad38dc] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 03/15/2024] [Accepted: 03/28/2024] [Indexed: 04/05/2024]
Abstract
Objective. Cochlear implants provide auditory perception to those with severe to profound sensorineural hearing loss: however, the quality of sound perceived by users does not approximate natural hearing. This limitation is due in part to the large physical gap between the stimulating electrodes and their target neurons. Therefore, directing the controlled outgrowth of processes from spiral ganglion neurons (SGNs) into close proximity to the electrode array could provide significantly increased hearing function.Approach.For this objective to be properly designed and implemented, the ability and limits of SGN neurites to be guided must first be determined. In this work, we engineer precise topographical microfeatures with angle turn challenges of various geometries to study SGN pathfinding and use live imaging to better understand how neurite growth is guided by these cues.Main Results.We find that the geometry of the angled microfeatures determines the ability of neurites to navigate the angled microfeature turns. SGN neurite pathfinding fidelity is increased by 20%-70% through minor increases in microfeature amplitude (depth) and by 25% if the angle of the patterned turn is made obtuse. Further, we see that dorsal root ganglion neuron growth cones change their morphology and migration to become more elongated within microfeatures. Our observations also indicate complexities in studying neurite turning. First, as the growth cone pathfinds in response to the various cues, the associated neurite often reorients across the angle topographical microfeatures. Additionally, neurite branching is observed in response to topographical guidance cues, most frequently when turning decisions are most uncertain.Significance.Overall, the multi-angle channel micropatterned substrate is a versatile and efficient system to assess neurite turning and pathfinding in response to topographical cues. These findings represent fundamental principles of neurite pathfinding that will be essential to consider for the design of 3D systems aiming to guide neurite growthin vivo.
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Affiliation(s)
- Joseph T Vecchi
- Department of Molecular Physiology and Biophysics, University of Iowa, Iowa City, IA, United States of America
- Department of Otolaryngology Head-Neck Surgery, University of Iowa, Iowa City, IA, United States of America
| | - Madeline Rhomberg
- Department of Otolaryngology Head-Neck Surgery, University of Iowa, Iowa City, IA, United States of America
| | - C Allan Guymon
- Department of Chemical and Biochemical Engineering, University of Iowa, Iowa City, IA, United States of America
| | - Marlan R Hansen
- Department of Molecular Physiology and Biophysics, University of Iowa, Iowa City, IA, United States of America
- Department of Otolaryngology Head-Neck Surgery, University of Iowa, Iowa City, IA, United States of America
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Rosenbalm TN, Levi NH, Morykwas MJ, Wagner WD. Electrical stimulation via repeated biphasic conducting materials for peripheral nerve regeneration. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2023; 34:61. [PMID: 37964030 PMCID: PMC10645611 DOI: 10.1007/s10856-023-06763-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Accepted: 10/26/2023] [Indexed: 11/16/2023]
Abstract
Improved materials for peripheral nerve repair are needed for the advancement of new surgical techniques in fields spanning from oncology to trauma. In this study, we developed bioresorbable materials capable of producing repeated electric field gradients spaced 600 μm apart to assess the impact on neuronal cell growth, and migration. Electrically conductive, biphasic composites comprised of poly (glycerol) sebacate acrylate (PGSA) alone, and doped with poly (pyrrole) (PPy), were prepared to create alternating segments with high and low electrically conductivity. Conductivity measurements demonstrated that 0.05% PPy added to PSA achieved an optimal value of 1.25 × 10-4 S/cm, for subsequent electrical stimulation. Tensile testing and degradation of PPy doped and undoped PGSA determined that 35-40% acrylation of PGSA matched nerve mechanical properties. Both fibroblast and neuronal cells thrived when cultured upon the composite. Biphasic PGSA/PPy sheets seeded with neuronal cells stimulated for with 3 V, 20 Hz demonstrated a 5x cell increase with 1 day of stimulation and up to a 10x cell increase with 3 days stimulation compared to non-stimulated composites. Tubular conduits composed of repeated high and low conductivity materials suitable for implantation in the rat sciatic nerve model for nerve repair were evaluated in vivo and were superior to silicone conduits. These results suggest that biphasic conducting conduits capable of maintaining mechanical properties without inducing compression injuries while generating repeated electric fields are a promising tool for acceleration of peripheral nerve repair to previously untreatable patients.
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Affiliation(s)
- Tabitha N Rosenbalm
- School of Biomedical Engineering and Sciences, Wake Forest University-Virginia Polytechnic Institute and State University, Winston-Salem, NC, 27106, USA
- Department of Plastic and Reconstructive Surgery, Wake Forest Baptist Health, Winston-Salem, NC, 27157, USA
| | - Nicole H Levi
- School of Biomedical Engineering and Sciences, Wake Forest University-Virginia Polytechnic Institute and State University, Winston-Salem, NC, 27106, USA.
- Department of Plastic and Reconstructive Surgery, Wake Forest Baptist Health, Winston-Salem, NC, 27157, USA.
| | - Michael J Morykwas
- School of Biomedical Engineering and Sciences, Wake Forest University-Virginia Polytechnic Institute and State University, Winston-Salem, NC, 27106, USA
- Department of Plastic and Reconstructive Surgery, Wake Forest Baptist Health, Winston-Salem, NC, 27157, USA
| | - William D Wagner
- School of Biomedical Engineering and Sciences, Wake Forest University-Virginia Polytechnic Institute and State University, Winston-Salem, NC, 27106, USA
- Department of Plastic and Reconstructive Surgery, Wake Forest Baptist Health, Winston-Salem, NC, 27157, USA
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Vecchi JT, Rhomberg M, Guymon CA, Hansen MR. The geometry of photopolymerized topography influences neurite pathfinding by directing growth cone morphology and migration. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.28.555111. [PMID: 37693432 PMCID: PMC10491164 DOI: 10.1101/2023.08.28.555111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/12/2023]
Abstract
Cochlear implants (CIs) provide auditory perception to those with profound sensorineural hearing loss: however, the quality of sound perceived by a CI user does not approximate natural hearing. This limitation is due in part to the large physical gap between the stimulating electrodes and their target neurons. Therefore, directing the controlled outgrowth of processes from spiral ganglion neurons (SGNs) into close proximity to the electrode array could provide significantly increased hearing function. For this objective to be properly designed and implemented, the ability and limits of SGN neurites to be guided must first be determined. In this work, we engineered precise topographical microfeatures with angle turn challenges of various geometries to study SGN pathfinding. Additionally, we analyze sensory neurite growth in response to topographically patterned substrates and use live imaging to better understand how neurite growth is guided by these cues. In assessing the ability of neurites to sense and turn in response to topographical cues, we find that the geometry of the angled microfeatures determines the ability of neurites to navigate the angled microfeature turns. SGN neurite pathfinding fidelity can be increased by 20-70% through minor increases in microfeature amplitude (depth) and by 25% if the angle of the patterned turn is made more obtuse. Further, by using engineered topographies and live imaging of dorsal root ganglion neurons (DRGNs), we see that DRGN growth cones change their morphology and migration to become more elongated within microfeatures. However, our observations also indicate complexities in studying neurite turning. First, as the growth cone pathfinds in response to the various cues, the associated neurite often reorients across the angle topographical microfeatures. This reorientation is likely related to the tension the neurite shaft experiences when the growth cone elongates in the microfeature around a turn. Additionally, neurite branching is observed in response to topographical guidance cues, most frequently when turning decisions are most uncertain. Overall, the multi-angle channel micropatterned substrate is a versatile and efficient system to assess SGN neurite turning and pathfinding in response to topographical cues. These findings represent fundamental principles of neurite pathfinding that will be essential to consider for the design of 3D systems aiming to guide neurite growth in vivo.
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Affiliation(s)
- Joseph T. Vecchi
- Department of Molecular Physiology and Biophysics, Carver College of Medicine, Iowa City, IA, USA
- Department of Otolaryngology Head-Neck Surgery, Carver College of Medicine, Iowa City, IA, USA
| | - Madeline Rhomberg
- Department of Otolaryngology Head-Neck Surgery, Carver College of Medicine, Iowa City, IA, USA
| | - C. Allan Guymon
- Department of Chemical and Biochemical Engineering, University of Iowa, Iowa City, IA, USA
| | - Marlan R. Hansen
- Department of Molecular Physiology and Biophysics, Carver College of Medicine, Iowa City, IA, USA
- Department of Otolaryngology Head-Neck Surgery, Carver College of Medicine, Iowa City, IA, USA
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Cheng X, Li T, Yan L, Jiao Y, Zhang Y, Wang K, Cheng Z, Ma J, Shao L. Biodegradable electrospinning superhydrophilic nanofiber membranes for ultrafast oil-water separation. SCIENCE ADVANCES 2023; 9:eadh8195. [PMID: 37611103 PMCID: PMC10446487 DOI: 10.1126/sciadv.adh8195] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Accepted: 07/21/2023] [Indexed: 08/25/2023]
Abstract
Although membrane technology has attracted considerable attention for oily wastewater treatment, the plastic waste generated from discarded membranes presents an immediate challenge for achieving eco-friendly separation. We designed on-demand biodegradable superhydrophilic membranes composed of polylactic acid nanofibers in conjunction with polyethylene oxide hydrogels using electrospinning technology for ultrafast purification of oily water. Our results showed that the use of the polyethylene oxide hydrogels increased the number of hydrogen bonds formed between the membrane surface and water molecules by 357.6%. This converted hydrophobic membranes into superhydrophilic ones, which prevented membrane fouling and accelerated emulsion penetration through the membranes. The oil-in-water emulsion permeance of our newly designed nanofiber membranes increased by 61.9 times (2.1 × 104 liters per square meter per hour per bar) with separation efficiency >99.6%, which was superior to state-of-the-art membranes. Moreover, the formation of hydrogen bonds was found to accelerate polylactic acid biodegradation into lactic acid by over 30%, offering a promising approach for waste membrane treatment.
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Affiliation(s)
- Xiquan Cheng
- State Key Laboratory of Urban Water Resource and Environment, School of Marine Science and Technology, Harbin Institute of Technology, Weihai 264209, P.R. China
- Shandong Sino-European Membrane Technology Research Institute Co. Ltd., Weihai Key Laboratory of Water Treatment and Membrane Technology, Weihai 264209, P.R. China
| | - Tongyu Li
- State Key Laboratory of Urban Water Resource and Environment, School of Marine Science and Technology, Harbin Institute of Technology, Weihai 264209, P.R. China
| | - Linlin Yan
- MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, School of Chemical Engineering and Technology, State Key Laboratory of Urban Water Resource and Environment (SKLUWRE), Harbin Institute of Technology, Harbin 150001, P.R. China
| | - Yang Jiao
- State Key Laboratory of Urban Water Resource and Environment, School of Marine Science and Technology, Harbin Institute of Technology, Weihai 264209, P.R. China
| | - Yingjie Zhang
- State Key Laboratory of Urban Water Resource and Environment, School of Marine Science and Technology, Harbin Institute of Technology, Weihai 264209, P.R. China
- Shandong Sino-European Membrane Technology Research Institute Co. Ltd., Weihai Key Laboratory of Water Treatment and Membrane Technology, Weihai 264209, P.R. China
| | - Kai Wang
- State Key Laboratory of Urban Water Resource and Environment, School of Marine Science and Technology, Harbin Institute of Technology, Weihai 264209, P.R. China
| | - Zhongjun Cheng
- MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, School of Chemical Engineering and Technology, State Key Laboratory of Urban Water Resource and Environment (SKLUWRE), Harbin Institute of Technology, Harbin 150001, P.R. China
| | - Jun Ma
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Lu Shao
- MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, School of Chemical Engineering and Technology, State Key Laboratory of Urban Water Resource and Environment (SKLUWRE), Harbin Institute of Technology, Harbin 150001, P.R. China
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Bridging the electrode-neuron gap: finite element modeling of in vitro neurotrophin gradients to optimize neuroelectronic interfaces in the inner ear. Acta Biomater 2022; 151:360-378. [PMID: 36007779 DOI: 10.1016/j.actbio.2022.08.035] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 08/13/2022] [Accepted: 08/16/2022] [Indexed: 11/23/2022]
Abstract
Although cochlear implant (CI) technology has allowed for the partial restoration of hearing over the last few decades, persistent challenges (e.g., poor performance in noisy environments and limited ability to decode intonation and music) remain. The "electrode-neuron gap" is inherent to these challenges and poses the most significant obstacle to advancing past the current plateau in CI performance. We propose the development of a "neuro-regenerative nexus"-a biological interface that doubly preserves native spiral ganglion neurons (SGNs) while precisely directing the growth of neurites arising from transplanted human pluripotent stem cell (hPSC)-derived otic neuronal progenitors (ONPs) toward the native SGN population. We hypothesized that the Polyhedrin Delivery System (PODS®-recombinant human brain-derived neurotrophic factor [rhBDNF]) could stably provide the adequate BDNF concentration gradient to hPSC-derived late-stage ONPs to facilitate otic neuronal differentiation and directional neurite outgrowth. To test this hypothesis, a finite element model (FEM) was constructed to simulate BDNF concentration profiles generated by PODS®-rhBDNF based on initial concentration and culture device geometry. For biological validation of the FEM, cell culture experiments assessing survival, differentiation, neurite growth direction, and synaptic connections were conducted using a multi-chamber microfluidic device. We were able to successfully generate the optimal BDNF concentration gradient to enable survival, neuronal differentiation toward SGNs, directed neurite extension of hPSC-derived SGNs, and synaptogenesis between two hPSC-derived SGN populations. This proof-of-concept study provides a step toward the next generation of CI technology. STATEMENT OF SIGNIFICANCE: Our study demonstrates that the generation of in vitro neurotrophin concentration gradients facilitates survival, neuronal differentiation toward auditory neurons, and directed neurite extension of human pluripotent stem cell-derived auditory neurons. These findings are indispensable to designing a bioactive cochlear implant, in which stem cell-derived neurons are integrated into a cochlear implant electrode strip, as the strategy will confer directional neurite growth from the transplanted cells in the inner ear. This study is the first to present the concept of a "neuro-regenerative nexus" congruent with a bioactive cochlear implant to eliminate the electrode-neuron gapthe most significant barrier to next-generation cochlear implant technology.
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Wu Y, Rakotoarisoa M, Angelov B, Deng Y, Angelova A. Self-Assembled Nanoscale Materials for Neuronal Regeneration: A Focus on BDNF Protein and Nucleic Acid Biotherapeutic Delivery. NANOMATERIALS 2022; 12:nano12132267. [PMID: 35808102 PMCID: PMC9268293 DOI: 10.3390/nano12132267] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 06/26/2022] [Accepted: 06/27/2022] [Indexed: 02/04/2023]
Abstract
Enabling challenging applications of nanomedicine and precision medicine in the treatment of neurodegenerative disorders requires deeper investigations of nanocarrier-mediated biomolecular delivery for neuronal targeting and recovery. The successful use of macromolecular biotherapeutics (recombinant growth factors, antibodies, enzymes, synthetic peptides, cell-penetrating peptide–drug conjugates, and RNAi sequences) in clinical developments for neuronal regeneration should benefit from the recent strategies for enhancement of their bioavailability. We highlight the advances in the development of nanoscale materials for drug delivery in neurodegenerative disorders. The emphasis is placed on nanoformulations for the delivery of brain-derived neurotrophic factor (BDNF) using different types of lipidic nanocarriers (liposomes, liquid crystalline or solid lipid nanoparticles) and polymer-based scaffolds, nanofibers and hydrogels. Self-assembled soft-matter nanoscale materials show favorable neuroprotective characteristics, safety, and efficacy profiles in drug delivery to the central and peripheral nervous systems. The advances summarized here indicate that neuroprotective biomolecule-loaded nanoparticles and injectable hydrogels can improve neuronal survival and reduce tissue injury. Certain recently reported neuronal dysfunctions in long-COVID-19 survivors represent early manifestations of neurodegenerative pathologies. Therefore, BDNF delivery systems may also help in prospective studies on recovery from long-term COVID-19 neurological complications and be considered as promising systems for personalized treatment of neuronal dysfunctions and prevention or retarding of neurodegenerative disorders.
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Affiliation(s)
- Yu Wu
- CNRS, Institut Galien Paris-Saclay, Université Paris-Saclay, F-92290 Châtenay-Malabry, France; (Y.W.); (M.R.)
| | - Miora Rakotoarisoa
- CNRS, Institut Galien Paris-Saclay, Université Paris-Saclay, F-92290 Châtenay-Malabry, France; (Y.W.); (M.R.)
| | - Borislav Angelov
- Institute of Physics, ELI Beamlines, Academy of Sciences of the Czech Republic, Na Slovance 2, CZ-18221 Prague, Czech Republic;
| | - Yuru Deng
- Wenzhou Institute, University of Chinese Academy of Sciences, No. 1, Jinlian Road, Longwan District, Wenzhou 325001, China;
| | - Angelina Angelova
- CNRS, Institut Galien Paris-Saclay, Université Paris-Saclay, F-92290 Châtenay-Malabry, France; (Y.W.); (M.R.)
- Correspondence:
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Current Concepts and Future Trends in Increasing the Benefits of Cochlear Implantation: A Narrative Review. Medicina (B Aires) 2022; 58:medicina58060747. [PMID: 35744010 PMCID: PMC9229893 DOI: 10.3390/medicina58060747] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 05/25/2022] [Accepted: 05/29/2022] [Indexed: 01/29/2023] Open
Abstract
Hearing loss is the most common neurosensory disorder, and with the constant increase in etiological factors, combined with early detection protocols, numbers will continue to rise. Cochlear implantation has become the gold standard for patients with severe hearing loss, and interest has shifted from implantation principles to the preservation of residual hearing following the procedure itself. As the audiological criteria for cochlear implant eligibility have expanded to include patients with good residual hearing, more attention is focused on complementary development of otoprotective agents, electrode design, and surgical approaches. The focus of this review is current aspects of preserving residual hearing through a summary of recent trends regarding surgical and pharmacological fundamentals. Subsequently, the assessment of new pharmacological options, novel bioactive molecules (neurotrophins, growth factors, etc.), nanoparticles, stem cells, and gene therapy are discussed.
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Wille I, Harre J, Oehmichen S, Lindemann M, Menzel H, Ehlert N, Lenarz T, Warnecke A, Behrens P. Development of Neuronal Guidance Fibers for Stimulating Electrodes: Basic Construction and Delivery of a Growth Factor. Front Bioeng Biotechnol 2022; 10:776890. [PMID: 35141211 PMCID: PMC8819688 DOI: 10.3389/fbioe.2022.776890] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Accepted: 01/05/2022] [Indexed: 12/03/2022] Open
Abstract
State-of-the-art treatment for sensorineural hearing loss is based on electrical stimulation of residual spiral ganglion neurons (SGNs) with cochlear implants (CIs). Due to the anatomical gap between the electrode contacts of the CI and the residual afferent fibers of the SGNs, spatial spreading of the stimulation signal hampers focused neuronal stimulation. Also, the efficiency of a CI is limited because SGNs degenerate over time due to loss of trophic support. A promising option to close the anatomical gap is to install fibers as artificial nerve guidance structures on the surface of the implant and install on these fibers drug delivery systems releasing neuroprotective agents. Here, we describe the first steps in this direction. In the present study, suture yarns made of biodegradable polymers (polyglycolide/poly-ε-caprolactone) serve as the basic fiber material. In addition to the unmodified fiber, also fibers modified with amine groups were employed. Cell culture investigations with NIH 3T3 fibroblasts attested good cytocompatibility to both types of fibers. The fibers were then coated with the extracellular matrix component heparan sulfate (HS) as a biomimetic of the extracellular matrix. HS is known to bind, stabilize, modulate, and sustainably release growth factors. Here, we loaded the HS-carrying fibers with the brain-derived neurotrophic factor (BDNF) which is known to act neuroprotectively. Release of this neurotrophic factor from the fibers was followed over a period of 110 days. Cell culture investigations with spiral ganglion cells, using the supernatants from the release studies, showed that the BDNF delivered from the fibers drastically increased the survival rate of SGNs in vitro. Thus, biodegradable polymer fibers with attached HS and loaded with BDNF are suitable for the protection and support of SGNs. Moreover, they present a promising base material for the further development towards a future neuronal guiding scaffold.
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Affiliation(s)
- Inga Wille
- Institut für Anorganische Chemie, Leibniz Universität Hannover, Hannover, Germany
- Cluster of Excellence Hearing4all, Hannover, Germany
| | - Jennifer Harre
- Cluster of Excellence Hearing4all, Hannover, Germany
- Department of Otorhinolaryngology, Head and Neck Surgery, Hannover Medical School, Hannover, Germany
| | - Sarah Oehmichen
- Institut für Technische Chemie, Technische Universität Braunschweig, Braunschweig, Germany
| | - Maren Lindemann
- Institut für Technische Chemie, Technische Universität Braunschweig, Braunschweig, Germany
| | - Henning Menzel
- Institut für Technische Chemie, Technische Universität Braunschweig, Braunschweig, Germany
| | - Nina Ehlert
- Institut für Anorganische Chemie, Leibniz Universität Hannover, Hannover, Germany
- Cluster of Excellence Hearing4all, Hannover, Germany
| | - Thomas Lenarz
- Cluster of Excellence Hearing4all, Hannover, Germany
- Department of Otorhinolaryngology, Head and Neck Surgery, Hannover Medical School, Hannover, Germany
| | - Athanasia Warnecke
- Cluster of Excellence Hearing4all, Hannover, Germany
- Department of Otorhinolaryngology, Head and Neck Surgery, Hannover Medical School, Hannover, Germany
| | - Peter Behrens
- Institut für Anorganische Chemie, Leibniz Universität Hannover, Hannover, Germany
- Cluster of Excellence Hearing4all, Hannover, Germany
- Cluster of Excellence PhoenixD, Hannover, Germany
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Brant JA, Adewole DO, Vitale F, Cullen DK. Bioengineering applications for hearing restoration: emerging biologically inspired and biointegrated designs. Curr Opin Biotechnol 2021; 72:131-138. [PMID: 34826683 DOI: 10.1016/j.copbio.2021.11.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Revised: 10/29/2021] [Accepted: 11/08/2021] [Indexed: 12/21/2022]
Abstract
Cochlear implantation has become the standard of care for hearing loss not amenable to amplification by bypassing the structures of the cochlea and stimulating the spiral ganglion neurons directly. Since the first single channel electrodes were implanted, significant advancements have been made: multi-channel arrays are now standard, they are softer to avoid damage to the cochlea and pre-curved to better position the electrode array adjacent to the nerve, and surgical and stimulation techniques have helped to conform to the anatomy and physiology of the cochlea. However, even with these advances the experience does not approach that of normal hearing. In order to make significant advances in performance, the next generation of implants will require novel interface technology. Advances in regenerative techniques, optogenetics, piezoelectric materials, and bioengineered living scaffolds hold the promise for the next generation of implantable hearing devices, and hope for the restoration of natural hearing.
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Affiliation(s)
- Jason A Brant
- Department of Otorhinolaryngology, Perelman School of Medicine, University of Pennsylvania, 3400 Spruce St., Philadelphia, PA 19104, USA; Center for Brain Injury & Repair, Department of Neurosurgery, University of Pennsylvania, 240 S. 33rd St., 301 Hayden Hall, Philadelphia, PA 19104, USA
| | - Dayo O Adewole
- Department of Otorhinolaryngology, Perelman School of Medicine, University of Pennsylvania, 3400 Spruce St., Philadelphia, PA 19104, USA; Center for Brain Injury & Repair, Department of Neurosurgery, University of Pennsylvania, 240 S. 33rd St., 301 Hayden Hall, Philadelphia, PA 19104, USA; Department of Bioengineering, School of Engineering and Applied, Science, University of Pennsylvania, 220 S 33rd St., Philadelphia, PA 19104, USA; Center for Brain Injury & Repair, Department of Neurosurgery, University of Pennsylvania, 3320 Smith Walk, 105 Hayden Hall, Philadelphia, PA 19104, USA; Center for Neuroengineering & Therapeutics, University of Pennsylvania, 3400 Spruce St., Philadelphia, PA 19104, USA
| | - Flavia Vitale
- Center for Brain Injury & Repair, Department of Neurosurgery, University of Pennsylvania, 240 S. 33rd St., 301 Hayden Hall, Philadelphia, PA 19104, USA; Department of Bioengineering, School of Engineering and Applied, Science, University of Pennsylvania, 220 S 33rd St., Philadelphia, PA 19104, USA; Department of Neurology, Perelman School of Medicine, University of Pennsylvania, 3400 Spruce St., Philadelphia, PA 19104, USA; Department of Physical Medicine & Rehabilitation, Perelman School of Medicine, University of Pennsylvania, 3400 Spruce St., Philadelphia, PA 19104, USA; Center for Neuroengineering & Therapeutics, University of Pennsylvania, 3400 Spruce St., Philadelphia, PA 19104, USA
| | - Daniel K Cullen
- Center for Brain Injury & Repair, Department of Neurosurgery, University of Pennsylvania, 240 S. 33rd St., 301 Hayden Hall, Philadelphia, PA 19104, USA; Department of Bioengineering, School of Engineering and Applied, Science, University of Pennsylvania, 220 S 33rd St., Philadelphia, PA 19104, USA; Center for Brain Injury & Repair, Department of Neurosurgery, University of Pennsylvania, 3320 Smith Walk, 105 Hayden Hall, Philadelphia, PA 19104, USA; Center for Neuroengineering & Therapeutics, University of Pennsylvania, 3400 Spruce St., Philadelphia, PA 19104, USA.
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11
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Huang Z, Xie Q, Li S, Zhou Y, He Z, Lin K, Yang M, Song P, Chen X. Promising Applications of Nanoparticles in the Treatment of Hearing Loss. Front Cell Dev Biol 2021; 9:750185. [PMID: 34692703 PMCID: PMC8529154 DOI: 10.3389/fcell.2021.750185] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Accepted: 09/09/2021] [Indexed: 01/10/2023] Open
Abstract
Hearing loss is one of the most common disabilities affecting both children and adults worldwide. However, traditional treatment of hearing loss has some limitations, particularly in terms of drug delivery system as well as diagnosis of ear imaging. The blood–labyrinth barrier (BLB), the barrier between the vasculature and fluids of the inner ear, restricts entry of most blood-borne compounds into inner ear tissues. Nanoparticles (NPs) have been demonstrated to have high biocompatibility, good degradation, and simple synthesis in the process of diagnosis and treatment, which are promising for medical applications in hearing loss. Although previous studies have shown that NPs have promising applications in the field of inner ear diseases, there is still a gap between biological research and clinical application. In this paper, we aim to summarize developments and challenges of NPs in diagnostics and treatment of hearing loss in recent years. This review may be useful to raise otology researchers’ awareness of effect of NPs on hearing diagnosis and treatment.
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Affiliation(s)
- Zilin Huang
- Department of Otorhinolaryngology, Head and Neck Surgery, Zhongnan Hospital of Wuhan University, Wuhan, China.,Sleep Medicine Center, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Qiang Xie
- Department of Otorhinolaryngology, Head and Neck Surgery, Zhongnan Hospital of Wuhan University, Wuhan, China.,Sleep Medicine Center, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Shuang Li
- Department of Otorhinolaryngology, Head and Neck Surgery, Zhongnan Hospital of Wuhan University, Wuhan, China.,Sleep Medicine Center, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Yuhao Zhou
- Department of Otorhinolaryngology, Head and Neck Surgery, Zhongnan Hospital of Wuhan University, Wuhan, China.,Sleep Medicine Center, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Zuhong He
- Department of Otorhinolaryngology, Head and Neck Surgery, Zhongnan Hospital of Wuhan University, Wuhan, China.,Sleep Medicine Center, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Kun Lin
- Department of Otorhinolaryngology, Head and Neck Surgery, Zhongnan Hospital of Wuhan University, Wuhan, China.,Sleep Medicine Center, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Minlan Yang
- Department of Otorhinolaryngology, Head and Neck Surgery, Zhongnan Hospital of Wuhan University, Wuhan, China.,Sleep Medicine Center, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Peng Song
- Department of Otorhinolaryngology, Head and Neck Surgery, Zhongnan Hospital of Wuhan University, Wuhan, China.,Sleep Medicine Center, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Xiong Chen
- Department of Otorhinolaryngology, Head and Neck Surgery, Zhongnan Hospital of Wuhan University, Wuhan, China.,Sleep Medicine Center, Zhongnan Hospital of Wuhan University, Wuhan, China
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12
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Liu T, Li Q, Yang S, Zhao T, Lin J, Ju T, Wen Z. CNTs-CaP/chitosan-coated AZ91D magnesium alloy extract promoted rat dorsal root ganglia neuron growth via activating ERK signalling pathway. Cell Biochem Funct 2021; 39:908-920. [PMID: 34296452 DOI: 10.1002/cbf.3662] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2021] [Revised: 06/24/2021] [Accepted: 06/29/2021] [Indexed: 01/19/2023]
Abstract
Increasing attention has been paid on the application of biodegradable materials such as magnesium and its alloys in neuron repair. AZ91D magnesium alloy coated with carbon nanotubes (CNTs) and/or calcium phosphate (CaP)/chitosan (CS) was fabricated in this study. To evaluate the bioactivity of these AZ91D-based composites, the extracts were prepared by immersing samples in modified simulated body fluid (m-SBF) for 0, 2, 8, 16, 24, 34, 44, 60, or 90 days. Immunofluorescence staining for neuronal class III β-tubulin (TUJ1) revealed that both CNTs-CaP/CS-AZ91D and CaP/CS-AZ91D extracts promoted axon outgrowth of dorsal root ganglia (DRG) neurons, accompanied with increased expression of phosphorylated focal adhesion kinase (p-FAK) and growth associated protein-43 (GAP-43). Besides, the extracts increased the expression and the release of neurotrophic factors including nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF). ERK signalling was activated in DRG neurons after treating with either CNTs-CaP/CS-AZ91D or CaP/CS-AZ91D extracts, and its inhibition with U0126 counteracted the beneficial effects of these extracts on DRG neuron. Overall, the extracts from these AZ91D-based composites might promote DRG neuron growth via activating ERK signalling pathway. Notably, CNTs-CaP/CS-AZ91D extracts showed a better promoting effect on neuron growth than CaP/CS-AZ91D. Assessment of ion elements showed that the addition of CNTs coating enhanced magnesium corrosion resistance and reduced the deposition of calcium and phosphorus on the surface of CaP/CS-AZ91D alloy. These findings demonstrate that CNTs-CaP/CS-AZ91D likely provide a more suitable environment for neuron growth, which suggests a potential implantable biomaterial for the treatment of nerve injury. SIGNIFICANCE: AZ91D magnesium alloy coated with carbon nanotubes (CNTs) and/or calcium phosphate (CaP)/chitosan (CS) was fabricated and their immersion extracts were prepared using modified simulated body fluid in this study. Both extracts from CNTs-CaP/CS and CaP/CS-coated AZ91D magnesium alloy promotes rat dorsal root ganglia (DRG) neuron growth via activating ERK signalling pathway. Notably, the addition of CNTs improves the performance of CaP/CS-AZ91D. For the first time, our research demonstrates that CNTs-CaP/CS-AZ91D likely provide a suitable environment for neuron growth, suggesting these AZ91D-based composites as potential implantable biomaterials for the treatment of nerve injury.
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Affiliation(s)
- Tingjiao Liu
- Department of Neurology, First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Qianqian Li
- Department of Neurology, First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Shanshan Yang
- Department of Neurology, First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Tingting Zhao
- Department of Neurology, First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Jinghan Lin
- Department of Neurology, First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Ting Ju
- Department of Neurology, First Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Zhaohui Wen
- Department of Neurology, First Affiliated Hospital of Harbin Medical University, Harbin, China
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13
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Interaction of micropatterned topographical and biochemical cues to direct neurite growth from spiral ganglion neurons. Hear Res 2021; 409:108315. [PMID: 34343850 DOI: 10.1016/j.heares.2021.108315] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Revised: 05/07/2021] [Accepted: 07/12/2021] [Indexed: 01/01/2023]
Abstract
Functional outcomes with neural prosthetic devices, such as cochlear implants, are limited in part due to physical separation between the stimulating elements and the neurons they stimulate. One strategy to close this gap aims to precisely guide neurite regeneration to position the neurites in closer proximity to electrode arrays. Here, we explore the ability of micropatterned biochemical and topographic guidance cues, singly and in combination, to direct the growth of spiral ganglion neuron (SGN) neurites, the neurons targeted by cochlear implants. Photopolymerization of methacrylate monomers was used to form unidirectional topographical features of ridges and grooves in addition to multidirectional patterns with 90o angle turns. Microcontact printing was also used to create similar uni- and multi-directional patterns of peptides on polymer surfaces. Biochemical cues included peptides that facilitate (laminin, LN) or repel (EphA4-Fc) neurite growth. On flat surfaces, SGN neurites preferentially grew on LN-coated stripes and avoided EphA4-Fc-coated stripes. LN or EphA4-Fc was selectively adsorbed onto the ridges or grooves to test the neurite response to a combination of topographical and biochemical cues. Coating the ridges with EphA4-Fc and grooves with LN lead to enhanced SGN alignment to topographical patterns. Conversely, EphA4-Fc coating on the grooves or LN coating on the ridges tended to disrupt alignment to topographical patterns. SGN neurites respond to combinations of topographical and biochemical cues and surface patterning that leverages both cues enhance guided neurite growth.
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14
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Wey K, Schirrmann R, Diesing D, Lang S, Brandau S, Hansen S, Epple M. Coating of cochlear implant electrodes with bioactive DNA-loaded calcium phosphate nanoparticles for the local transfection of stimulatory proteins. Biomaterials 2021; 276:121009. [PMID: 34280824 DOI: 10.1016/j.biomaterials.2021.121009] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2021] [Revised: 06/23/2021] [Accepted: 07/02/2021] [Indexed: 12/12/2022]
Abstract
Calcium phosphate nanoparticles were loaded with nucleic acids to enhance the on-growth of tissue to a cochlear implant electrode. The nanoparticle deposition on a metallic electrode surface is possible by electrophoretic deposition (EPD) or layer-by-layer deposition (LbL). Impedance spectroscopy showed that the coating layer did not interrupt the electrical conductance at physiological frequencies and beyond (1-40,000 Hz). The transfection was demonstrated with the model cell lines HeLa and 3T3 as well as with primary explanted spiral ganglion neurons (rat) with the model protein enhanced green fluorescent protein (EGFP). The expression of the functional protein brain-derived neurotrophic factor (BDNF) was also shown. Thus, a coating of inner-ear cochlear implant electrodes with nanoparticles that carry nucleic acids will enhance the ongrowth of spiral ganglion cell axons for an improved transmission of electrical pulses.
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Affiliation(s)
- Karolin Wey
- Inorganic Chemistry and Centre for Nanointegration Duisburg-Essen (CeNIDE), University of Duisburg-Essen, Essen, Germany
| | - Ronja Schirrmann
- Department of Otorhinolaryngology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Detlef Diesing
- Physical Chemistry, University of Duisburg-Essen, Essen, Germany
| | - Stephan Lang
- Department of Otorhinolaryngology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Sven Brandau
- Department of Otorhinolaryngology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Stefan Hansen
- Department of Otorhinolaryngology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Matthias Epple
- Inorganic Chemistry and Centre for Nanointegration Duisburg-Essen (CeNIDE), University of Duisburg-Essen, Essen, Germany.
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15
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Sun F, Zhou K, Tian KY, Zhang XY, Liu W, Wang J, Zhong CP, Qiu JH, Zha DJ. Atrial Natriuretic Peptide Promotes Neurite Outgrowth and Survival of Cochlear Spiral Ganglion Neurons in vitro Through NPR-A/cGMP/PKG Signaling. Front Cell Dev Biol 2021; 9:681421. [PMID: 34268307 PMCID: PMC8276373 DOI: 10.3389/fcell.2021.681421] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Accepted: 05/10/2021] [Indexed: 01/22/2023] Open
Abstract
Sensorineural hearing loss (SNHL) is a dominant public health issue affecting millions of people around the globe, which is correlated with the irreversible deterioration of the hair cells and spiral ganglion neurons (SGNs) within the cochlea. Strategies using bioactive molecules that regulate neurite regeneration and neuronal survival to reestablish connections between auditory epithelium or implanted electrodes and SGN neurites would become attractive therapeutic candidates for SNHL. As an intracellular second messenger, cyclic guanosine-3’,5’-monophosphate (cGMP) can be synthesized through activation of particulate guanylate cyclase-coupled natriuretic peptide receptors (NPRs) by natriuretic peptides, which in turn modulates multiple aspects of neuronal functions including neuronal development and neuronal survival. As a cardiac-derived hormone, atrial natriuretic peptide (ANP), and its specific receptors (NPR-A and NPR-C) are broadly expressed in the nervous system where they might be involved in the maintenance of diverse neural functions. Despite former literatures and our reports indicating the existence of ANP and its receptors within the inner ear, particularly in the spiral ganglion, their potential regulatory mechanisms underlying functional properties of auditory neurons are still incompletely understood. Our recently published investigation revealed that ANP could promote the neurite outgrowth of SGNs by activating NPR-A/cGMP/PKG cascade in a dose-dependent manner. In the present research, the influence of ANP and its receptor-mediated downstream signaling pathways on neurite outgrowth, neurite attraction, and neuronal survival of SGNs in vitro was evaluated by employing cultures of organotypic explant and dissociated neuron from postnatal rats. Our data indicated that ANP could support and attract neurite outgrowth of SGNs and possess a high capacity to improve neuronal survival of SGNs against glutamate-induced excitotoxicity by triggering the NPR-A/cGMP/PKG pathway. The neuroregenerative and neuroprotective effects of ANP/NPRA/cGMP/PKG-dependent signaling on SGNs would represent an attractive therapeutic candidate for hearing impairment.
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Affiliation(s)
- Fei Sun
- Department of Otolaryngology-Head and Neck Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, China
| | - Ke Zhou
- Department of Laboratory Medicine, Institute of Clinical Laboratory Medicine of PLA, Xijing Hospital, Fourth Military Medical University, Xi'an, China
| | - Ke-Yong Tian
- Department of Otolaryngology-Head and Neck Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, China
| | - Xin-Yu Zhang
- Department of Otolaryngology-Head and Neck Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, China
| | - Wei Liu
- Department of Otolaryngology-Head and Neck Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, China
| | - Jie Wang
- Department of Otolaryngology-Head and Neck Surgery, The Affiliated Children Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Cui-Ping Zhong
- Department of Otolaryngology-Head and Neck Surgery, The 940th Hospital of Joint Logistics Support Force of PLA, Lanzhou, China
| | - Jian-Hua Qiu
- Department of Otolaryngology-Head and Neck Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, China
| | - Ding-Jun Zha
- Department of Otolaryngology-Head and Neck Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an, China
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16
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Li CY, Mittal R, Bergman J, Mittal J, Eshraghi AA. Recent advancements toward gapless neural-electrode interface post-cochlear implantation. Neural Regen Res 2021; 16:1805-1806. [PMID: 33510086 PMCID: PMC8328784 DOI: 10.4103/1673-5374.306085] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Affiliation(s)
- Crystal Y Li
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Rahul Mittal
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Jenna Bergman
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Jeenu Mittal
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Adrien A Eshraghi
- Department of Otolaryngology; Department of Neurological Surgery, University of Miami Miller School of Medicine, Miami; Department of Biomedical Engineering, University of Miami, Coral Gables, FL, USA
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17
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Chang HT, Heuer RA, Oleksijew AM, Coots KS, Roque CB, Nella KT, McGuire TL, Matsuoka AJ. An engineered three-dimensional stem cell niche in the inner ear by applying a nanofibrillar cellulose hydrogel with a sustained-release neurotrophic factor delivery system. Acta Biomater 2020; 108:111-127. [PMID: 32156626 PMCID: PMC7198367 DOI: 10.1016/j.actbio.2020.03.007] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Revised: 02/01/2020] [Accepted: 03/03/2020] [Indexed: 11/17/2022]
Abstract
Although the application of human embryonic stem cells (hESCs) in stem cell-replacement therapy remains promising, its potential is hindered by a low cell survival rate in post-transplantation within the inner ear. Here, we aim to enhance the in vitro and in vivo survival rate and neuronal differentiation of otic neuronal progenitors (ONPs) by generating an artificial stem cell niche consisting of three-dimensional (3D) hESC-derived ONP spheroids with a nanofibrillar cellulose hydrogel and a sustained-release brain-derivative neurotrophic factor delivery system. Our results demonstrated that the transplanted hESC-derived ONP spheroids survived and neuronally differentiated into otic neuronal lineages in vitro and in vivo and also extended neurites toward the bony wall of the cochlea 90 days after the transplantation without the use of immunosuppressant medication. Our data in vitro and in vivo presented here provide sufficient evidence that we have established a robust, reproducible protocol for in vivo transplantation of hESC-derived ONPs to the inner ear. Using our protocol to create an artificial stem cell niche in the inner ear, it is now possible to work on integrating transplanted hESC-derived ONPs further and also to work toward achieving functional auditory neurons generated from hESCs. Our findings suggest that the provision of an artificial stem cell niche can be a future approach to stem cell-replacement therapy for inner-ear regeneration. STATEMENT OF SIGNIFICANCE: Inner ear regeneration utilizing human embryonic stem cell-derived otic neuronal progenitors (hESC-derived ONPs) has remarkable potential for treating sensorineural hearing loss. However, the local environment of the inner ear requires a suitable stem cell niche to allow hESC-derived ONP engraftment as well as neuronal differentiation. To overcome this obstacle, we utilized three-dimensional spheroid formation (direct contact), nanofibrillar cellulose hydrogel (extracellular matrix), and a neurotrophic factor delivery system to artificially create a stem cell niche in vitro and in vivo. Our in vitro and in vivo data presented here provide sufficient evidence that we have established a robust, reproducible protocol for in vivo transplantation of hESC-derived ONPs to the inner ear.
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Affiliation(s)
- Hsiang-Tsun Chang
- Department of Otolaryngology and Head and Neck Surgery, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Rachel A Heuer
- Department of Otolaryngology and Head and Neck Surgery, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Andrew M Oleksijew
- Department of Otolaryngology and Head and Neck Surgery, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Kyle S Coots
- Department of Otolaryngology and Head and Neck Surgery, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Christian B Roque
- Department of Otolaryngology and Head and Neck Surgery, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Kevin T Nella
- Department of Otolaryngology and Head and Neck Surgery, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Tammy L McGuire
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago IL 60611, USA
| | - Akihiro J Matsuoka
- Department of Otolaryngology and Head and Neck Surgery, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA; Department of Communication Sciences and Disorders, Northwestern University, Evanston, IL 60201, USA; Hugh Knowles Center for Hearing Research, Northwestern University, Evanston, IL 60201, USA.
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18
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Dalrymple AN, Robles UA, Huynh M, Nayagam BA, Green RA, Poole-Warren LA, Fallon JB, Shepherd RK. Electrochemical and biological performance of chronically stimulated conductive hydrogel electrodes. J Neural Eng 2020; 17:026018. [DOI: 10.1088/1741-2552/ab7cfc] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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19
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Leso V, Fontana L, Ercolano ML, Romano R, Iavicoli I. Opportunities and challenging issues of nanomaterials in otological fields: an occupational health perspective. Nanomedicine (Lond) 2019; 14:2613-2629. [PMID: 31609676 DOI: 10.2217/nnm-2019-0114] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Nanotechnology may offer innovative solutions to overcome the physiological and anatomical barriers that make the diagnosis and treatment of ear diseases an extremely challenging issue. However, despite the solutions provided by nano-applications, the still little-known toxicological behavior of nanomaterials raised scientific concerns regarding their biosafety for treated patients and exposed workers. Therefore, this review provides an overview on recent developments and upcoming opportunities in nanoscale otological applications, and critically assesses possible adverse effects of nanosized compounds on ear structures and hearing functionality. Although such preliminary data do not allow to draw definite strategies for the evaluation of nanomaterial ototoxicity, they can still be useful to improve scientific community and workforce awareness regarding possible nanomaterial adverse effects on ear.
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Affiliation(s)
- Veruscka Leso
- Department of Public Health, Section of Occupational Medicine, University of Naples Federico II, Via Sergio Pansini 5, 80131 Naples, Italy
| | - Luca Fontana
- Department of Occupational & Environmental Medicine, Epidemiology & Hygiene, Italian Workers' Compensation Authority (INAIL), Via di Fontana Candida 1, 00040 Monte Porzio Catone, Rome, Italy
| | - Maria Luigia Ercolano
- Department of Public Health, Section of Occupational Medicine, University of Naples Federico II, Via Sergio Pansini 5, 80131 Naples, Italy
| | - Rosaria Romano
- Department of Public Health, Section of Occupational Medicine, University of Naples Federico II, Via Sergio Pansini 5, 80131 Naples, Italy
| | - Ivo Iavicoli
- Department of Public Health, Section of Occupational Medicine, University of Naples Federico II, Via Sergio Pansini 5, 80131 Naples, Italy
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20
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Dombrowski T, Rankovic V, Moser T. Toward the Optical Cochlear Implant. Cold Spring Harb Perspect Med 2019; 9:cshperspect.a033225. [PMID: 30323016 DOI: 10.1101/cshperspect.a033225] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
When hearing fails, cochlear implants (CIs) provide open speech perception to most of the currently half a million CI users. CIs bypass the defective sensory organ and stimulate the auditory nerve electrically. The major bottleneck of current CIs is the poor coding of spectral information, which results from wide current spread from each electrode contact. As light can be more conveniently confined, optical stimulation of the auditory nerve presents a promising perspective for a fundamental advance of CIs. Moreover, given the improved frequency resolution of optical excitation and its versatility for arbitrary stimulation patterns the approach also bears potential for auditory research. Here, we review the current state of the art focusing on the emerging concept of optogenetic stimulation of the auditory pathway. Developing optogenetic stimulation for auditory research and future CIs requires efforts toward viral gene transfer to the neurons, design and characterization of appropriate optogenetic actuators, as well as engineering of multichannel optical implants.
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Affiliation(s)
- Tobias Dombrowski
- Institute for Auditory Neuroscience and InnerEarLab, University Medical Center, 37075 Göttingen, Germany.,Department of Otorhinolaryngology, Head and Neck Surgery, Ruhr University Bochum, St. Elisabeth Hospital, 44787 Bochum, Germany
| | - Vladan Rankovic
- Institute for Auditory Neuroscience and InnerEarLab, University Medical Center, 37075 Göttingen, Germany.,Auditory Neuroscience and Optogenetics Group, German Primate Center, 37077 Göttingen, Germany
| | - Tobias Moser
- Institute for Auditory Neuroscience and InnerEarLab, University Medical Center, 37075 Göttingen, Germany.,Auditory Neuroscience and Optogenetics Group, German Primate Center, 37077 Göttingen, Germany.,Auditory Neuroscience Group, Max-Planck-Institute for Experimental Medicine, 37075 Göttingen, Germany
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21
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Bas E, Anwar MR, Goncalves S, Dinh CT, Bracho OR, Chiossone JA, Van De Water TR. Laminin-coated electrodes improve cochlear implant function and post-insertion neuronal survival. Neuroscience 2019; 410:97-107. [PMID: 31059743 DOI: 10.1016/j.neuroscience.2019.04.048] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Revised: 04/17/2019] [Accepted: 04/24/2019] [Indexed: 12/20/2022]
Abstract
The benefits of Cochlear implant (CI) technology depend among other factors on the proximity of the electrode array to the spiral ganglion neurons. Laminin, a component of the extracellular matrix, regulates Schwann cell proliferation and survival as well as reorganization of actin fibers within their cytoskeleton, which is necessary for myelination of peripheral axons. In this study we explore the effectiveness of laminin-coated electrodes in promoting neuritic outgrowth from auditory neurons towards the electrode array and the ability to reduce acoustic and electric auditory brainstem response (i.e. aABR and eABR) thresholds. In vitro: Schwann cells and neurites are attracted towards laminin-coated surfaces with longer neuritic processes in laminin-coated dishes compared to uncoated dishes. In vivo: Animals implanted with laminin-coated electrodes experience significant decreases in eABR and aABR thresholds at selected frequencies compared to the results from the uncoated electrodes group. At 1 month post implantation there were a greater number of spiral ganglion neurons and neuritic processes projecting into the scala tympani of animals implanted with laminin-coated electrodes compared to animals with uncoated electrodes. These data suggest that Schwann cells are attracted towards laminin-coated electrodes and promote neuritic outgrowth/ guidance and promote the survival of spiral ganglion neurons following electrode insertion trauma.
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Affiliation(s)
- Esperanza Bas
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, United States of America.
| | - Mir R Anwar
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, United States of America
| | - Stefania Goncalves
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, United States of America
| | - Christine T Dinh
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, United States of America
| | - Olena R Bracho
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, United States of America
| | - Juan A Chiossone
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, United States of America
| | - Thomas R Van De Water
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, FL, United States of America
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22
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Zhao M, Xu Y, Xie M, Zou L, Wang Z, Liu S, Zhao Q. Halogenated Aza-BODIPY for Imaging-Guided Synergistic Photodynamic and Photothermal Tumor Therapy. Adv Healthc Mater 2018; 7:e1800606. [PMID: 30047582 DOI: 10.1002/adhm.201800606] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Revised: 06/25/2018] [Indexed: 01/07/2023]
Abstract
It is always a huge challenge to develop novel near-infrared (NIR) phototherapeutic agents suitable for imaging-guided cancer therapy. In order to clarify the positive heavy atom effects on the photodynamic and photothermal efficiencies of phototherapeutic agents, a series of chlorine-, bromide-, or iodine-substituted aza-BODIPYs (B2, B3, and B4, respectively) are designed and synthesized. Among them, B4 exhibits both excellent photodynamic and photothermal effects (singlet oxygen yield of B4 is 1.57 times more than that of B3) and excellent photothermal effects (1.3 °C higher than that of B3). Then, nanoparticles of B4 (IABNs) with excellent biocompatibility are prepared by coating hydrophobic B4 with hydrophilic polymer DSPE-mPEG5000 . IABN exhibits high photostability, excellent biocompatibility, and low dark toxicity both in vivo and in vitro. Furthermore, IABN shows the enhanced photodynamic effect and high photothermal conversion efficiency (34.8%). In addition, the strong fluorescence emission of IABN makes it suitable for fluorescence imaging-guided tumor therapy in vivo. Finally, IABN has successfully healed the Hela tumor-bearing mice under NIR fluorescence imaging- and photothermal imaging-guided synergistic photothermal and photodynamic therapy with low side effects, demonstrating that it is promising for future clinical applications.
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Affiliation(s)
- Menglong Zhao
- Key Laboratory for Organic Electronics and Information Displays & Jiangsu Key Laboratory for Biosensors; Institute of Advanced Materials (IAM); Nanjing University of Posts and Telecommunications (NUPT); Nanjing 210023 P. R. China
| | - Yunjian Xu
- Key Laboratory for Organic Electronics and Information Displays & Jiangsu Key Laboratory for Biosensors; Institute of Advanced Materials (IAM); Nanjing University of Posts and Telecommunications (NUPT); Nanjing 210023 P. R. China
| | - Mingjuan Xie
- Key Laboratory for Organic Electronics and Information Displays & Jiangsu Key Laboratory for Biosensors; Institute of Advanced Materials (IAM); Nanjing University of Posts and Telecommunications (NUPT); Nanjing 210023 P. R. China
| | - Liang Zou
- Key Laboratory for Organic Electronics and Information Displays & Jiangsu Key Laboratory for Biosensors; Institute of Advanced Materials (IAM); Nanjing University of Posts and Telecommunications (NUPT); Nanjing 210023 P. R. China
| | - Zhaoli Wang
- Key Laboratory for Organic Electronics and Information Displays & Jiangsu Key Laboratory for Biosensors; Institute of Advanced Materials (IAM); Nanjing University of Posts and Telecommunications (NUPT); Nanjing 210023 P. R. China
| | - Shujuan Liu
- Key Laboratory for Organic Electronics and Information Displays & Jiangsu Key Laboratory for Biosensors; Institute of Advanced Materials (IAM); Nanjing University of Posts and Telecommunications (NUPT); Nanjing 210023 P. R. China
| | - Qiang Zhao
- Key Laboratory for Organic Electronics and Information Displays & Jiangsu Key Laboratory for Biosensors; Institute of Advanced Materials (IAM); Nanjing University of Posts and Telecommunications (NUPT); Nanjing 210023 P. R. China
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Chen N, Luo B, Yang IH, Thakor NV, Ramakrishna S. Biofunctionalized platforms towards long-term neural interface. CURRENT OPINION IN BIOMEDICAL ENGINEERING 2018. [DOI: 10.1016/j.cobme.2018.03.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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Schmidt N, Schulze J, Warwas DP, Ehlert N, Lenarz T, Warnecke A, Behrens P. Long-term delivery of brain-derived neurotrophic factor (BDNF) from nanoporous silica nanoparticles improves the survival of spiral ganglion neurons in vitro. PLoS One 2018; 13:e0194778. [PMID: 29584754 PMCID: PMC5870973 DOI: 10.1371/journal.pone.0194778] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Accepted: 03/11/2018] [Indexed: 11/18/2022] Open
Abstract
Sensorineural hearing loss (SNHL) can be overcome by electrical stimulation of spiral ganglion neurons (SGNs) via a cochlear implant (CI). Restricted CI performance results from the spatial gap between the SGNs and the electrode, but the efficacy of CI is also limited by the degeneration of SGNs as one consequence of SHNL. In the healthy cochlea, the survival of SGNs is assured by endogenous neurotrophic support. Several applications of exogenous neurotrophic supply have been shown to reduce SGN degeneration in vitro and in vivo. In the present study, nanoporous silica nanoparticles (NPSNPs), with an approximate diameter of <100 nm, were loaded with the brain-derived neurotrophic factor (BDNF) to test their efficacy as long-term delivery system for neurotrophins. The neurotrophic factor was released constantly from the NPSNPs over a release period of 80 days when the surface of the nanoparticles had been modified with amino groups. Cell culture investigations with NIH3T3 fibroblasts attest a good general cytocompatibility of the NPSNPs. In vitro experiments with SGNs indicate a significantly higher survival rate of SGNs in cell cultures that contained BDNF-loaded nanoparticles compared to the control culture with unloaded NPSNPs (p<0.001). Importantly, also the amounts of BDNF released up to a time period of 39 days increased the survival rate of SGNs. Thus, NPSNPs carrying BDNF are suitable for the treatment of inner ear disease and for the protection and the support of SGNs. Their nanoscale nature and the fact that a direct contact of the nanoparticles and the SGNs is not necessary for neuroprotective effects, should allow for the facile preparation of nanocomposites, e.g., with biocompatible polymers, to install coatings on implants for the realization of implant-based growth factor delivery systems.
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Affiliation(s)
- Nadeschda Schmidt
- Institut für Anorganische Chemie, Leibniz Universität Hannover, Hannover, Germany
- Cluster of Excellence Hearing4all, Hannover, Germany
| | - Jennifer Schulze
- Cluster of Excellence Hearing4all, Hannover, Germany
- Department of Otorhinolaryngology, Head and Neck Surgery, Hannover Medical School, Hannover, Germany
| | - Dawid P. Warwas
- Institut für Anorganische Chemie, Leibniz Universität Hannover, Hannover, Germany
| | - Nina Ehlert
- Institut für Anorganische Chemie, Leibniz Universität Hannover, Hannover, Germany
- Cluster of Excellence Hearing4all, Hannover, Germany
| | - Thomas Lenarz
- Cluster of Excellence Hearing4all, Hannover, Germany
- Department of Otorhinolaryngology, Head and Neck Surgery, Hannover Medical School, Hannover, Germany
| | - Athanasia Warnecke
- Cluster of Excellence Hearing4all, Hannover, Germany
- Department of Otorhinolaryngology, Head and Neck Surgery, Hannover Medical School, Hannover, Germany
| | - Peter Behrens
- Institut für Anorganische Chemie, Leibniz Universität Hannover, Hannover, Germany
- Cluster of Excellence Hearing4all, Hannover, Germany
- * E-mail:
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Detecting ligand interactions in real time on living bacterial cells. Appl Microbiol Biotechnol 2018; 102:4193-4201. [PMID: 29550990 PMCID: PMC5895670 DOI: 10.1007/s00253-018-8919-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2017] [Revised: 03/05/2018] [Accepted: 03/06/2018] [Indexed: 11/04/2022]
Abstract
Time-resolved analysis assays of receptor-ligand interactions are fundamental in basic research and drug discovery. Adequate methods are well developed for the analysis of recombinant proteins such as antibody-antigen interactions. However, assays for time-resolved ligand-binding processes on living cells are still rare, in particular within microbiology. In this report, the real-time cell-binding assay (RT-CBA) technology LigandTracer®, originally designed for mammalian cell culture, was extended to cover Gram-positive and Gram-negative bacteria. This required the development of new immobilization methods for bacteria, since LigandTracer depends on cells being firmly attached to a Petri dish. The evaluated Escherichia coli CJ236 and BL21 as well as Staphylococcus carnosus TM300 strains were immobilized to plastic Petri dishes using antibody capture, allowing us to depict kinetic binding traces of fluorescently labeled antibodies directed against surface-displayed bacterial proteins for as long as 10–15 h. Interaction parameters, such as the affinity and kinetic constants, could be estimated with high precision (coefficient of variation 9–44%) and the bacteria stayed viable for at least 16 h. The other tested attachment protocols were inferior to the antibody capture approach. Our attachment protocol is generic and could potentially also be applied to other assays and purposes.
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Qi D, Liu Z, Liu Y, Jiang Y, Leow WR, Pal M, Pan S, Yang H, Wang Y, Zhang X, Yu J, Li B, Yu Z, Wang W, Chen X. Highly Stretchable, Compliant, Polymeric Microelectrode Arrays for In Vivo Electrophysiological Interfacing. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2017; 29:1702800. [PMID: 28869690 DOI: 10.1002/adma.201702800] [Citation(s) in RCA: 89] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Revised: 07/05/2017] [Indexed: 06/07/2023]
Abstract
Polymeric microelectrode arrays (MEAs) are emerging as a new generation of biointegrated microelectrodes to transduce original electrochemical signals in living tissues to external electrical circuits, and vice versa. So far, the challenge of stretchable polymeric MEAs lies in the competition between high stretchability and good electrode-substrate adhesion. The larger the stretchability, the easier the delamination of electrodes from the substrate due to the mismatch in their Young's modulus. In this work, polypyrrole (PPy) electrode materials are designed, with PPy nanowires integrated on the high conductive PPy electrode arrays. By utilizing this electrode material, for the first time, stretchable polymeric MEAs are fabricated with both high stretchability (≈100%) and good electrode-substrate adhesion (1.9 MPa). In addition, low Young's modulus (450 kPa), excellent recycling stability (10 000 cycles of stretch), and high conductivity of the MEAs are also achieved. As a proof of concept, the as-prepared polymeric MEAs are successfully used for conformally recording the electrocorticograph signals from rats in normal and epileptic states, respectively. Further, these polymeric MEAs are also successful in stimulating the ischiadic nerve of the rat. This strategy provides a new perspective to the highly stretchable and mechanically stable polymeric MEAs, which are vital for compliant neural electrodes.
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Affiliation(s)
- Dianpeng Qi
- School of Materials Science and Engineering, Nanyang Technological University, 639798, Singapore
| | - Zhiyuan Liu
- School of Materials Science and Engineering, Nanyang Technological University, 639798, Singapore
| | - Yan Liu
- School of Materials Science and Engineering, Nanyang Technological University, 639798, Singapore
| | - Ying Jiang
- School of Materials Science and Engineering, Nanyang Technological University, 639798, Singapore
| | - Wan Ru Leow
- School of Materials Science and Engineering, Nanyang Technological University, 639798, Singapore
| | - Mayank Pal
- School of Materials Science and Engineering, Nanyang Technological University, 639798, Singapore
| | - Shaowu Pan
- School of Materials Science and Engineering, Nanyang Technological University, 639798, Singapore
| | - Hui Yang
- School of Materials Science and Engineering, Nanyang Technological University, 639798, Singapore
| | - Yu Wang
- School of Materials Science and Engineering, Nanyang Technological University, 639798, Singapore
| | - Xiaoqian Zhang
- School of Materials Science and Engineering, Nanyang Technological University, 639798, Singapore
| | - Jiancan Yu
- School of Materials Science and Engineering, Nanyang Technological University, 639798, Singapore
| | - Bin Li
- School of Materials Science and Engineering, Nanyang Technological University, 639798, Singapore
| | - Zhe Yu
- Institute of Biomedical and Health Engineering, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen University Town, 1068 Xueyuan Avenue, Shenzhen, 518055, P. R. China
| | - Wei Wang
- State Key Laboratory of Urban Water Resource and Environment, School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin, 150090, P. R. China
| | - Xiaodong Chen
- School of Materials Science and Engineering, Nanyang Technological University, 639798, Singapore
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