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Toulemonde P, Beck C, Risoud M, Lemesre PE, Tardivel M, Siepmann J, Vincent C. Development of a Semi-Automated Approach for the Quantification of Neuronal Cells in the Spiral Ganglion of the Whole Implanted Gerbil Cochlea, Acquired by Light-Sheet Microscopy. Audiol Neurootol 2024; 29:500-507. [PMID: 38810615 DOI: 10.1159/000539569] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2024] [Accepted: 05/20/2024] [Indexed: 05/31/2024] Open
Abstract
INTRODUCTION Assessing cochlear implantation's impact on cell loss and preventing post-implant cochlear damage are key areas of focus for hearing preservation research. The preservation of auditory neuronal and sensory neural hearing cells has a positive impact on auditory perception after implantation. This study aimed to provide details on a semi-automated spiral ganglion neuronal cell counting method, developed using whole implanted gerbil cochlea acquisitions with light-sheet microscopy. METHODS Mongolian gerbils underwent right cochlear implantation with an electrode array whose silicone was loaded with dexamethasone or not and were euthanized 10 weeks after implantation. The cochleae were prepared according to a 29-day protocol, with the electrode array in place. Light-sheet microscopy was used for acquisition, and Imaris software was employed for three-dimensional analysis of the cochleas and semi-automatic quantification of spiral ganglion cells. The imaJ software was used for the manual quantification of these cells. RESULTS Six cochleae were acquired by light-sheet microscopy, allowing good identification of cells. There was no significant difference between the mean number of spiral ganglion cells obtained by manual and semi-automatic counting (p = 0.25). CONCLUSION Light-sheet microscopy provided complete visualization of the spiral ganglion and cell identification. The semi-automated counting method developed using Imaris software tools proved reliable and efficient and could be applied to a larger sample to assess post-cochlear implant cell damage and the efficacy of protective drugs delivered to the inner ear.
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Affiliation(s)
- Philippine Toulemonde
- Department of Otology and Neurotology, Lille University Hospital, University of Lille, Lille, France
- INSERM U1008 - Controlled Drug Delivery Systems and Biomaterials, Lille, France
| | - Cyril Beck
- Department of Otology and Neurotology, Lille University Hospital, University of Lille, Lille, France
- INSERM U1008 - Controlled Drug Delivery Systems and Biomaterials, Lille, France
| | - Michaël Risoud
- Department of Otology and Neurotology, Lille University Hospital, University of Lille, Lille, France
- INSERM U1008 - Controlled Drug Delivery Systems and Biomaterials, Lille, France
| | - Pierre Emmanuel Lemesre
- Department of Otology and Neurotology, Lille University Hospital, University of Lille, Lille, France
- INSERM U1008 - Controlled Drug Delivery Systems and Biomaterials, Lille, France
| | - Meryem Tardivel
- BioImaging Center Lille-Nord de France (BICeL), University Lille, Lille, France
| | - Juergen Siepmann
- Department of Otology and Neurotology, Lille University Hospital, University of Lille, Lille, France
- INSERM U1008 - Controlled Drug Delivery Systems and Biomaterials, Lille, France
| | - Christophe Vincent
- Department of Otology and Neurotology, Lille University Hospital, University of Lille, Lille, France
- INSERM U1008 - Controlled Drug Delivery Systems and Biomaterials, Lille, France
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Wu PZ, O'Malley JT, Liberman MC. Neural Degeneration in Normal-Aging Human Cochleas: Machine-Learning Counts and 3D Mapping in Archival Sections. J Assoc Res Otolaryngol 2023; 24:499-511. [PMID: 37957485 PMCID: PMC10695900 DOI: 10.1007/s10162-023-00909-y] [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: 01/12/2023] [Accepted: 09/03/2023] [Indexed: 11/15/2023] Open
Abstract
Quantifying the survival patterns of spiral ganglion cells (SGCs), the cell bodies of auditory-nerve fibers, is critical to studies of sensorineural hearing loss, especially in human temporal bones. The classic method of manual counting is tedious, and, although stereology approaches can be faster, they can only be used to estimate total cell numbers per cochlea. Here, a machine-learning algorithm that automatically identifies, counts, and maps the SGCs in digitized images of semi-serial human temporal-bone sections not only speeds the analysis, with no loss of accuracy, but also allows 3D visualization of the SGCs and fine-grained mapping to cochlear frequency. Applying the algorithm to 62 normal-aging human ears shows significantly faster degeneration of SGCs in the basal than the apical half of the cochlea. Comparison to fiber counts in the same ears shows that the fraction of surviving SGCs lacking a peripheral axon steadily increases with age, reaching more than 50% in the apical cochlea and almost 66% in basal regions.
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Affiliation(s)
- Pei-Zhe Wu
- Eaton-Peabody Laboratories, Massachusetts Eye and Ear Infirmary, 243 Charles St., Boston, MA, 02114-3096, USA.
- Department of Otolaryngology, Harvard Medical School, Boston, MA, 02115, USA.
| | - Jennifer T O'Malley
- Eaton-Peabody Laboratories, Massachusetts Eye and Ear Infirmary, 243 Charles St., Boston, MA, 02114-3096, USA
- Department of Otolaryngology, Harvard Medical School, Boston, MA, 02115, USA
| | - M Charles Liberman
- Eaton-Peabody Laboratories, Massachusetts Eye and Ear Infirmary, 243 Charles St., Boston, MA, 02114-3096, USA
- Department of Otolaryngology, Harvard Medical School, Boston, MA, 02115, USA
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Moatti A, Cai Y, Li C, Popowski KD, Cheng K, Ligler FS, Greenbaum A. Tissue clearing and three-dimensional imaging of the whole cochlea and vestibular system from multiple large-animal models. STAR Protoc 2023; 4:102220. [PMID: 37060559 PMCID: PMC10140170 DOI: 10.1016/j.xpro.2023.102220] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Revised: 01/27/2023] [Accepted: 03/13/2023] [Indexed: 04/16/2023] Open
Abstract
The inner ear of humans and large animals is embedded in a thick and dense bone that makes dissection challenging. Here, we present a protocol that enables three-dimensional (3D) characterization of intact inner ears from large-animal models. We describe steps for decalcifying bone, using solvents to remove color and lipids, and imaging tissues in 3D using confocal and light sheet microscopy. We then detail a pipeline to count hair cells in antibody-stained and 3D imaged cochleae using open-source software. For complete details on the use and execution of this protocol, please refer to (Moatti et al., 2022).1.
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Affiliation(s)
- Adele Moatti
- Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill and North Carolina State University, Raleigh, NC 27606, USA; Comparative Medicine Institute, North Carolina State University, Raleigh, NC 27606, USA
| | - Yuheng Cai
- Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill and North Carolina State University, Raleigh, NC 27606, USA; Comparative Medicine Institute, North Carolina State University, Raleigh, NC 27606, USA
| | - Chen Li
- Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill and North Carolina State University, Raleigh, NC 27606, USA; Comparative Medicine Institute, North Carolina State University, Raleigh, NC 27606, USA
| | - Kristen D Popowski
- Comparative Medicine Institute, North Carolina State University, Raleigh, NC 27606, USA; College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27606, USA
| | - Ke Cheng
- Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill and North Carolina State University, Raleigh, NC 27606, USA; Comparative Medicine Institute, North Carolina State University, Raleigh, NC 27606, USA; College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27606, USA
| | - Frances S Ligler
- Department of Biomedical Engineering, Texas A&M University, College Station, TX 77843, USA
| | - Alon Greenbaum
- Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill and North Carolina State University, Raleigh, NC 27606, USA; Comparative Medicine Institute, North Carolina State University, Raleigh, NC 27606, USA.
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Urata S, Okabe S. Three-dimensional mouse cochlea imaging based on the modified Sca/eS using confocal microscopy. Anat Sci Int 2023:10.1007/s12565-023-00703-z. [PMID: 36773194 DOI: 10.1007/s12565-023-00703-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Accepted: 01/13/2023] [Indexed: 02/12/2023]
Abstract
The three-dimensional stria vascularis (SV) and cochlear blood vessel structure is essential for inner ear function. Here, modified Sca/eS, a sorbitol-based optical-clearing method, was reported to visualize SV and vascular structure in the intact mouse cochlea. Cochlear macrophages as well as perivascular-resident macrophage-like melanocytes were detected as GFP-positive cells of the CX3CR1+/GFP mice. This study's method was effective in elucidating inner ear function under both physiological and pathological conditions.
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Affiliation(s)
- Shinji Urata
- Department of Otolaryngology, Graduate School of Medicine, University of Tokyo, Tokyo, 113-0033, Japan.
| | - Shigeo Okabe
- Department of Cellular Neurobiology, Graduate School of Medicine, the University of Tokyo, Tokyo, Japan
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Toward Personalized Diagnosis and Therapy for Hearing Loss: Insights From Cochlear Implants. Otol Neurotol 2022; 43:e903-e909. [PMID: 35970169 DOI: 10.1097/mao.0000000000003624] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
ABSTRACT Sensorineural hearing loss (SNHL) is the most common sensory deficit, disabling nearly half a billion people worldwide. The cochlear implant (CI) has transformed the treatment of patients with SNHL, having restored hearing to more than 800,000 people. The success of CIs has inspired multidisciplinary efforts to address the unmet need for personalized, cellular-level diagnosis, and treatment of patients with SNHL. Current limitations include an inability to safely and accurately image at high resolution and biopsy the inner ear, precluding the use of key structural and molecular information during diagnostic and treatment decisions. Furthermore, there remains a lack of pharmacological therapies for hearing loss, which can partially be attributed to challenges associated with new drug development. We highlight advances in diagnostic and therapeutic strategies for SNHL that will help accelerate the push toward precision medicine. In addition, we discuss technological improvements for the CI that will further enhance its functionality for future patients. This report highlights work that was originally presented by Dr. Stankovic as part of the Dr. John Niparko Memorial Lecture during the 2021 American Cochlear Implant Alliance annual meeting.
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Ontogeny of cellular organization and LGR5 expression in porcine cochlea revealed using tissue clearing and 3D imaging. iScience 2022; 25:104695. [PMID: 35865132 PMCID: PMC9294204 DOI: 10.1016/j.isci.2022.104695] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 04/20/2022] [Accepted: 06/27/2022] [Indexed: 11/23/2022] Open
Abstract
Over 11% of the world's population experience hearing loss. Although there are promising studies to restore hearing in rodent models, the size, ontogeny, genetics, and frequency range of hearing of most rodents' cochlea do not match that of humans. The porcine cochlea can bridge this gap as it shares many anatomical, physiological, and genetic similarities with its human counterpart. Here, we provide a detailed methodology to process and image the porcine cochlea in 3D using tissue clearing and light-sheet microscopy. The resulting 3D images can be employed to compare cochleae across different ages and conditions, investigate the ontogeny of cochlear cytoarchitecture, and produce quantitative expression maps of LGR5, a marker of cochlear progenitors in mice. These data reveal that hair cell organization, inner ear morphology, cellular cartography in the organ of Corti, and spatiotemporal expression of LGR5 are dynamic over developmental stages in a pattern not previously documented.
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Toulemonde P, Risoud M, Lemesre P, Tardivel M, Siepmann J, Vincent C. 3D analysis of gerbil cochlea with cochlear implant. Eur Ann Otorhinolaryngol Head Neck Dis 2022; 139:333-336. [DOI: 10.1016/j.anorl.2022.03.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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8
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Dyer L, Parker A, Paphiti K, Sanderson J. Lightsheet Microscopy. Curr Protoc 2022; 2:e448. [PMID: 35838628 DOI: 10.1002/cpz1.448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
In this paper, we review lightsheet (selective plane illumination) microscopy for mouse developmental biologists. There are different means of forming the illumination sheet, and we discuss these. We explain how we introduced the lightsheet microscope economically into our core facility and present our results on fixed and living samples. We also describe methods of clearing fixed samples for three-dimensional imaging and discuss the various means of preparing samples with particular reference to mouse cilia, adipose spheroids, and cochleae. © 2022 The Authors. Current Protocols published by Wiley Periodicals LLC.
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Affiliation(s)
- Laura Dyer
- MRC Harwell Institute, Mammalian Genetics Unit, Harwell Campus, Oxfordshire, UK
| | - Andrew Parker
- MRC Harwell Institute, Mammalian Genetics Unit, Harwell Campus, Oxfordshire, UK
| | - Keanu Paphiti
- MRC Harwell Institute, Mammalian Genetics Unit, Harwell Campus, Oxfordshire, UK
| | - Jeremy Sanderson
- MRC Harwell Institute, Mammalian Genetics Unit, Harwell Campus, Oxfordshire, UK
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9
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Lutz BT, Hutson KA, Trecca EMC, Hamby M, Fitzpatrick DC. Neural Contributions to the Cochlear Summating Potential: Spiking and Dendritic Components. J Assoc Res Otolaryngol 2022; 23:351-363. [PMID: 35254541 DOI: 10.1007/s10162-022-00842-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Accepted: 02/21/2022] [Indexed: 11/30/2022] Open
Abstract
Using electrocochleography, the summating potential (SP) is a deflection from baseline to tones and an early rise in the response to clicks. Here, we use normal hearing gerbils and gerbils with outer hair cells removed with a combination of furosemide and kanamycin to investigate cellular origins of the SP. Round window electrocochleography to tones and clicks was performed before and after application of tetrodotoxin to prevent action potentials, and then again after kainic acid to prevent generation of an EPSP. With appropriate subtractions of the response curves from the different conditions, the contributions to the SP from outer hair cells, inner hair cell, and neural "spiking" and "dendritic" responses were isolated. Like hair cells, the spiking and dendritic components had opposite polarities to tones - the dendritic component had negative polarity and the spiking component had positive polarity. The magnitude of the spiking component was larger than the dendritic across frequencies and intensities. The onset to tones and to clicks followed a similar sequence; the outer hair cells responded first, then inner hair cells, then the dendritic component, and then the compound action potential of the spiking response. These results show the sources of the SP include at least the four components studied, and that these have a mixture of polarities and magnitudes that vary across frequency and intensity. Thus, multiple possible interactions must be considered when interpreting the SP for clinical uses.
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Affiliation(s)
- Brendan T Lutz
- The University of North Carolina at Chapel Hill, Department of Otolaryngology - Head & Neck Surgery, 101 Mason Farm Rd, CB#7546, Chapel Hill, NC, USA
| | - Kendall A Hutson
- The University of North Carolina at Chapel Hill, Department of Otolaryngology - Head & Neck Surgery, 101 Mason Farm Rd, CB#7546, Chapel Hill, NC, USA
| | - Eleonora M C Trecca
- IRCCS Casa Sollievo Della Sofferenza, Department of Maxillofacial Surgery and Otolaryngology, San Giovanni Rotondo (Foggia), Italy.,University Hospital of Foggia, Department of Otolaryngology- Head and Neck Surgery, Foggia, Italy
| | - Meredith Hamby
- The University of North Carolina at Chapel Hill, Department of Otolaryngology - Head & Neck Surgery, 101 Mason Farm Rd, CB#7546, Chapel Hill, NC, USA
| | - Douglas C Fitzpatrick
- The University of North Carolina at Chapel Hill, Department of Otolaryngology - Head & Neck Surgery, 101 Mason Farm Rd, CB#7546, Chapel Hill, NC, USA.
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10
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Vogl C, Neef J, Wichmann C. Methods for multiscale structural and functional analysis of the mammalian cochlea. Mol Cell Neurosci 2022; 120:103720. [DOI: 10.1016/j.mcn.2022.103720] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 02/13/2022] [Accepted: 03/08/2022] [Indexed: 01/11/2023] Open
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11
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Toulemonde P, Risoud M, Lemesre PE, Beck C, Wattelet J, Tardivel M, Siepmann J, Vincent C. Evaluation of the Efficacy of Dexamethasone-Eluting Electrode Array on the Post-Implant Cochlear Fibrotic Reaction by Three-Dimensional Immunofluorescence Analysis in Mongolian Gerbil Cochlea. J Clin Med 2021; 10:jcm10153315. [PMID: 34362099 PMCID: PMC8347204 DOI: 10.3390/jcm10153315] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Revised: 07/22/2021] [Accepted: 07/26/2021] [Indexed: 11/16/2022] Open
Abstract
Cochlear implant is the method of choice for the rehabilitation of severe to profound sensorineural hearing loss. The study of the tissue response to cochlear implantation and the prevention of post-cochlear-implant damages are areas of interest in hearing protection research. The objective was to assess the efficacy of dexamethasone-eluting electrode array on endo canal fibrosis formation by three-dimensional immunofluorescence analysis in implanted Mongolian gerbil cochlea. Two trials were conducted after surgery using Mongolian gerbil implanted with dexamethasone-eluting or non-eluting intracochlear electrode arrays. The animals were then euthanised 10 weeks after implantation. The cochleae were prepared (electrode array in place) according to a 29-day protocol with immunofluorescent labelling and tissue clearing. The acquisition was carried out using light-sheet microscopy. Imaris software was then used for three-dimensional analysis of the cochleae and quantification of the fibrotic volume. The analysis of 12 cochleae showed a significantly different mean volume of fibrosis (2.16 × 108 μm3 ± 0.15 in the dexamethasone eluting group versus 3.17 × 108 μm3 ± 0.54 in the non-eluting group) (p = 0.004). The cochlear implant used as a corticosteroid delivery system appears to be an encouraging device for the protection of the inner ear against fibrosis induced by implantation. Three-dimensional analysis of the cochlea by light-sheet microscopy was suitable for studying post-implantation tissue damage.
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Affiliation(s)
- Philippine Toulemonde
- Department of Otology and Neurotology, CHU Lille, University of Lille 2 Henri Warembourg, F-59000 Lille, France; (M.R.); (P.E.L.); (C.B.); (J.W.); (J.S.); (C.V.)
- INSERM U1008—Controlled Drug Delivery Systems and Biomaterials, F-59000 Lille, France
- Correspondence: ; Tel.: +33-6851-91052
| | - Michaël Risoud
- Department of Otology and Neurotology, CHU Lille, University of Lille 2 Henri Warembourg, F-59000 Lille, France; (M.R.); (P.E.L.); (C.B.); (J.W.); (J.S.); (C.V.)
- INSERM U1008—Controlled Drug Delivery Systems and Biomaterials, F-59000 Lille, France
| | - Pierre Emmanuel Lemesre
- Department of Otology and Neurotology, CHU Lille, University of Lille 2 Henri Warembourg, F-59000 Lille, France; (M.R.); (P.E.L.); (C.B.); (J.W.); (J.S.); (C.V.)
- INSERM U1008—Controlled Drug Delivery Systems and Biomaterials, F-59000 Lille, France
| | - Cyril Beck
- Department of Otology and Neurotology, CHU Lille, University of Lille 2 Henri Warembourg, F-59000 Lille, France; (M.R.); (P.E.L.); (C.B.); (J.W.); (J.S.); (C.V.)
- INSERM U1008—Controlled Drug Delivery Systems and Biomaterials, F-59000 Lille, France
| | - Jean Wattelet
- Department of Otology and Neurotology, CHU Lille, University of Lille 2 Henri Warembourg, F-59000 Lille, France; (M.R.); (P.E.L.); (C.B.); (J.W.); (J.S.); (C.V.)
- INSERM U1008—Controlled Drug Delivery Systems and Biomaterials, F-59000 Lille, France
| | - Meryem Tardivel
- BioImaging Center Lille-Nord de France (BICeL), University of Lille 2 Henri Warembourg, F-59000 Lille, France;
| | - Juergen Siepmann
- Department of Otology and Neurotology, CHU Lille, University of Lille 2 Henri Warembourg, F-59000 Lille, France; (M.R.); (P.E.L.); (C.B.); (J.W.); (J.S.); (C.V.)
- INSERM U1008—Controlled Drug Delivery Systems and Biomaterials, F-59000 Lille, France
| | - Christophe Vincent
- Department of Otology and Neurotology, CHU Lille, University of Lille 2 Henri Warembourg, F-59000 Lille, France; (M.R.); (P.E.L.); (C.B.); (J.W.); (J.S.); (C.V.)
- INSERM U1008—Controlled Drug Delivery Systems and Biomaterials, F-59000 Lille, France
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Keppeler D, Kampshoff CA, Thirumalai A, Duque-Afonso CJ, Schaeper JJ, Quilitz T, Töpperwien M, Vogl C, Hessler R, Meyer A, Salditt T, Moser T. Multiscale photonic imaging of the native and implanted cochlea. Proc Natl Acad Sci U S A 2021; 118:e2014472118. [PMID: 33903231 PMCID: PMC8106341 DOI: 10.1073/pnas.2014472118] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The cochlea of our auditory system is an intricate structure deeply embedded in the temporal bone. Compared with other sensory organs such as the eye, the cochlea has remained poorly accessible for investigation, for example, by imaging. This limitation also concerns the further development of technology for restoring hearing in the case of cochlear dysfunction, which requires quantitative information on spatial dimensions and the sensorineural status of the cochlea. Here, we employed X-ray phase-contrast tomography and light-sheet fluorescence microscopy and their combination for multiscale and multimodal imaging of cochlear morphology in species that serve as established animal models for auditory research. We provide a systematic reference for morphological parameters relevant for cochlear implant development for rodent and nonhuman primate models. We simulate the spread of light from the emitters of the optical implants within the reconstructed nonhuman primate cochlea, which indicates a spatially narrow optogenetic excitation of spiral ganglion neurons.
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Affiliation(s)
- Daniel Keppeler
- Institute for Auditory Neuroscience, University Medical Center Göttingen, 37075 Göttingen, Germany
- InnerEarLab, University Medical Center Göttingen, 37075 Göttingen, Germany
| | - Christoph A Kampshoff
- Institute for Auditory Neuroscience, University Medical Center Göttingen, 37075 Göttingen, Germany
- InnerEarLab, University Medical Center Göttingen, 37075 Göttingen, Germany
- Department of Otolaryngology, University Medical Center Göttingen, 37075 Göttingen, Germany
| | - Anupriya Thirumalai
- Institute for Auditory Neuroscience, University Medical Center Göttingen, 37075 Göttingen, Germany
- InnerEarLab, University Medical Center Göttingen, 37075 Göttingen, Germany
| | - Carlos J Duque-Afonso
- Institute for Auditory Neuroscience, University Medical Center Göttingen, 37075 Göttingen, Germany
- InnerEarLab, University Medical Center Göttingen, 37075 Göttingen, Germany
| | - Jannis J Schaeper
- Institute for X-ray Physics, University of Göttingen, 37075 Göttingen, Germany
| | - Tabea Quilitz
- Institute for Auditory Neuroscience, University Medical Center Göttingen, 37075 Göttingen, Germany
- InnerEarLab, University Medical Center Göttingen, 37075 Göttingen, Germany
| | - Mareike Töpperwien
- Institute for X-ray Physics, University of Göttingen, 37075 Göttingen, Germany
| | - Christian Vogl
- Institute for Auditory Neuroscience, University Medical Center Göttingen, 37075 Göttingen, Germany
- InnerEarLab, University Medical Center Göttingen, 37075 Göttingen, Germany
| | | | - Alexander Meyer
- InnerEarLab, University Medical Center Göttingen, 37075 Göttingen, Germany
- Department of Otolaryngology, University Medical Center Göttingen, 37075 Göttingen, Germany
| | - Tim Salditt
- Institute for X-ray Physics, University of Göttingen, 37075 Göttingen, Germany
- Cluster of Excellence "Multiscale Bioimaging: From Molecular Machines to Networks of Excitable Cells," University of Göttingen, 37075 Göttingen, Germany
| | - Tobias Moser
- Institute for Auditory Neuroscience, University Medical Center Göttingen, 37075 Göttingen, Germany;
- InnerEarLab, University Medical Center Göttingen, 37075 Göttingen, Germany
- Department of Otolaryngology, University Medical Center Göttingen, 37075 Göttingen, Germany
- Cluster of Excellence "Multiscale Bioimaging: From Molecular Machines to Networks of Excitable Cells," University of Göttingen, 37075 Göttingen, Germany
- Auditory Neuroscience and Optogenetics Laboratory, German Primate Center, 37075 Göttingen, Germany
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In Situ 3D-Imaging of the Inner Ear Synapses with a Cochlear Implant. Life (Basel) 2021; 11:life11040301. [PMID: 33915846 PMCID: PMC8066088 DOI: 10.3390/life11040301] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 03/27/2021] [Accepted: 03/28/2021] [Indexed: 11/17/2022] Open
Abstract
In recent years sensorineural hearing loss was found to affect not exclusively, nor at first, the sensory cells of the inner ear. The sensory cells' synapses and subsequent neurites are initially damaged. Auditory synaptopathies also play an important role in cochlear implant (CI) care, as they can lead to a loss of physiological hearing in patients with residual hearing. These auditory synaptopathies and in general the cascades of hearing pathologies have been in the focus of research in recent years with the aim to develop more targeted and individually tailored therapeutics. In the current study, a method to examine implanted inner ears of guinea pigs was developed to examine the synapse level. For this purpose, the cochlea is made transparent and scanned with the implant in situ using confocal laser scanning microscopy. Three different preparation methods were compared to enable both an overview image of the cochlea for assessing the CI position and images of the synapses on the same specimen. The best results were achieved by dissection of the bony capsule of the cochlea.
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Moatti A, Cai Y, Li C, Sattler T, Edwards L, Piedrahita J, Ligler FS, Greenbaum A. Three-dimensional imaging of intact porcine cochlea using tissue clearing and custom-built light-sheet microscopy. BIOMEDICAL OPTICS EXPRESS 2020; 11:6181-6196. [PMID: 33282483 PMCID: PMC7687970 DOI: 10.1364/boe.402991] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 09/26/2020] [Accepted: 09/30/2020] [Indexed: 05/03/2023]
Abstract
Hearing loss is a prevalent disorder that affects people of all ages. On top of the existing hearing aids and cochlear implants, there is a growing effort to regenerate functional tissues and restore hearing. However, studying and evaluating these regenerative medicine approaches in a big animal model (e.g. pigs) whose anatomy, physiology, and organ size are similar to a human is challenging. In big animal models, the cochlea is bulky, intricate, and veiled in a dense and craggy otic capsule. These facts complicate 3D microscopic analysis that is vital in the cochlea, where structure-function relation is time and again manifested. To allow 3D imaging of an intact cochlea of newborn and juvenile pigs with a volume up to ∼ 250 mm3, we adapted the BoneClear tissue clearing technique, which renders the bone transparent. The transparent cochleae were then imaged with cellular resolution and in a timely fashion, which prevented bubble formation and tissue degradation, using an adaptive custom-built light-sheet fluorescence microscope. The adaptive light-sheet microscope compensated for deflections of the illumination beam by changing the angles of the beam and translating the detection objective while acquiring images. Using this combination of techniques, macroscopic and microscopic properties of the cochlea were extracted, including the density of hair cells, frequency maps, and lower frequency limits. Consequently, the proposed platform could support the growing effort to regenerate cochlear tissues and assist with basic research to advance cures for hearing impairments.
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Affiliation(s)
- Adele Moatti
- Joint Department of Biomedical Engineering, North Carolina State University and University of North Carolina at Chapel Hill, Raleigh, NC 27695, USA
- Comparative Medicine Institute, North Carolina State University, Raleigh, NC 27695, USA
| | - Yuheng Cai
- Joint Department of Biomedical Engineering, North Carolina State University and University of North Carolina at Chapel Hill, Raleigh, NC 27695, USA
- Comparative Medicine Institute, North Carolina State University, Raleigh, NC 27695, USA
| | - Chen Li
- Joint Department of Biomedical Engineering, North Carolina State University and University of North Carolina at Chapel Hill, Raleigh, NC 27695, USA
- Comparative Medicine Institute, North Carolina State University, Raleigh, NC 27695, USA
| | - Tyler Sattler
- Joint Department of Biomedical Engineering, North Carolina State University and University of North Carolina at Chapel Hill, Raleigh, NC 27695, USA
- Comparative Medicine Institute, North Carolina State University, Raleigh, NC 27695, USA
| | - Laura Edwards
- Comparative Medicine Institute, North Carolina State University, Raleigh, NC 27695, USA
- Department of Molecular Biomedical Sciences, North Carolina State University, Raleigh, NC 27695, USA
| | - Jorge Piedrahita
- Comparative Medicine Institute, North Carolina State University, Raleigh, NC 27695, USA
- Department of Molecular Biomedical Sciences, North Carolina State University, Raleigh, NC 27695, USA
| | - Frances S. Ligler
- Joint Department of Biomedical Engineering, North Carolina State University and University of North Carolina at Chapel Hill, Raleigh, NC 27695, USA
- Comparative Medicine Institute, North Carolina State University, Raleigh, NC 27695, USA
| | - Alon Greenbaum
- Joint Department of Biomedical Engineering, North Carolina State University and University of North Carolina at Chapel Hill, Raleigh, NC 27695, USA
- Comparative Medicine Institute, North Carolina State University, Raleigh, NC 27695, USA
- Bioinformatics Research Center, North Carolina State University, Raleigh, NC 27695, USA
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