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Connolly K, Gonzalez-Cordero A. Modelling inner ear development and disease using pluripotent stem cells - a pathway to new therapeutic strategies. Dis Model Mech 2022; 15:dmm049593. [PMID: 36331565 PMCID: PMC10621662 DOI: 10.1242/dmm.049593] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2023] Open
Abstract
The sensory epithelia of the mammalian inner ear enable sound and movement to be perceived. Damage to these epithelia can cause irreversible sensorineural hearing loss and vestibular dysfunction because they lack regenerative capacity. The human inner ear cannot be biopsied without causing permanent damage, significantly limiting the tissue samples available for research. Investigating disease pathology and therapeutic developments have therefore traditionally relied on animal models, which often cannot completely recapitulate the human otic systems. These challenges are now being partly addressed using induced pluripotent stem cell-derived cultures, which generate the sensory epithelial-like tissues of the inner ear. Here, we review how pluripotent stem cells have been used to produce two-dimensional and three-dimensional otic cultures, the strengths and limitations of these new approaches, and how they have been employed to investigate genetic and acquired forms of audiovestibular dysfunction. This Review provides an overview of the progress in pluripotent stem cell-derived otic cultures thus far, focusing on their applications in disease modelling and therapeutic trials. We survey their current limitations and future directions, highlighting their prospective utility for high-throughput drug screening and developing personalised medicine approaches.
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Affiliation(s)
- Keeva Connolly
- Stem Cell Medicine Group, Children's Medical Research Institute, Westmead, 2145 NSW, Australia
- School of Medical Sciences, Faculty of Medicine and Health, University of Sydney, Westmead, 2145 NSW, Australia
| | - Anai Gonzalez-Cordero
- Stem Cell Medicine Group, Children's Medical Research Institute, Westmead, 2145 NSW, Australia
- School of Medical Sciences, Faculty of Medicine and Health, University of Sydney, Westmead, 2145 NSW, Australia
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2
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Genetic Mechanism Study of Auditory Phoenix Spheres and Transcription Factors Prediction for Direct Reprogramming by Bioinformatics. Int J Mol Sci 2022; 23:ijms231810287. [PMID: 36142199 PMCID: PMC9499413 DOI: 10.3390/ijms231810287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Revised: 08/25/2022] [Accepted: 08/27/2022] [Indexed: 11/17/2022] Open
Abstract
Background: Hearing loss is the most common irreversible sensory disorder. By delivering regenerative cells into the cochlea, cell-based therapy provides a novel strategy for hearing restoration. Recently, newly-identified phoenix cells have drawn attention due to their nearly unlimited self-renewal and neural differentiation capabilities. They are a promising cell source for cell therapy and a potential substitute for induced pluripotent stem cells (iPSCs) in many in vitro applications. However, the underlying genomic mechanism of their self-renewal capabilities is largely unknown. The aim of this study was to identify hub genes and potential molecular mechanisms between differentiated and undifferentiated phoenix cells and predict transcription factors (TFs) for direct reprogramming. Material and Methods: The datasets were downloaded from the ArrayExpress database. Samples of differentiated and undifferentiated phoenix cells with three biological replicates were utilised for bioinformatic analysis. Differentially expressed genes (DEGs) were screened and the Gene Ontology (GO) terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment were investigated. The gene set enrichment analysis (GSEA) was conducted to verify the enrichment of four self-defined gene set collections, followed by protein-protein interaction (PPI) network construction and subcluster analysis. The prediction of TFs for direct reprogramming was performed based on the TRANSFAC database. Results: Ten hub genes were identified to be the key candidates for self-renewal. Ten TFs were predicted as the direct reprogramming factors. This study provides a theoretical foundation for understanding phoenix cells and clues for direct reprogramming, which would stimulate further experiments and clinical applications in hearing research and treatment.
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Lee MP, Waldhaus J. In vitro and in vivo models: What have we learnt about inner ear regeneration and treatment for hearing loss? Mol Cell Neurosci 2022; 120:103736. [PMID: 35577314 PMCID: PMC9551661 DOI: 10.1016/j.mcn.2022.103736] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 04/29/2022] [Accepted: 05/10/2022] [Indexed: 01/07/2023] Open
Abstract
The sensory cells of the inner ear, called hair cells, do not regenerate spontaneously and therefore, hair cell loss and subsequent hearing loss are permanent in humans. Conversely, functional hair cell regeneration can be observed in non-mammalian vertebrate species like birds and fish. Also, during postnatal development in mice, limited regenerative capacity and the potential to isolate stem cells were reported. Together, these findings spurred the interest of current research aiming to investigate the endogenous regenerative potential in mammals. In this review, we summarize current in vitro based approaches and briefly introduce different in vivo model organisms utilized to study hair cell regeneration. Furthermore, we present an overview of the findings that were made synergistically using both, the in vitro and in vivo based tools.
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Affiliation(s)
- Mary P Lee
- Department of Otolaryngology-Head and Neck Surgery, Kresge Hearing Research Institute, University of Michigan, Ann Arbor, MI 48109, USA
| | - Joerg Waldhaus
- Department of Otolaryngology-Head and Neck Surgery, Kresge Hearing Research Institute, University of Michigan, Ann Arbor, MI 48109, USA.
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4
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Kurihara S, Fujioka M, Hirabayashi M, Yoshida T, Hosoya M, Nagase M, Kato F, Ogawa K, Okano H, Kojima H, Okano HJ. OUP accepted manuscript. Stem Cells Transl Med 2022; 11:282-296. [PMID: 35356976 PMCID: PMC8968745 DOI: 10.1093/stcltm/szab023] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2021] [Accepted: 11/26/2021] [Indexed: 11/12/2022] Open
Abstract
The spiral ganglion of the cochlea is essential for hearing and contains primary bipolar neurons that relay action potentials generated by mechanosensory hair cells. Injury to spiral ganglion neurons (SGNs) causes permanent hearing loss because these cells have limited regenerative capacity. Establishment of human cell-derived inner ear tissue in vitro could facilitate the development of treatments for hearing loss. Here, we report a stepwise protocol for differentiating human-induced pluripotent stem cells (hiPSCs) into otic organoids that contain SGN-like cells and demonstrate that otic organoids have potential for use as an experimental model of drug-induced neuropathy. Otic progenitor cells (OPCs) were created by 2D culture of hiPSCs for 9 days. Otic spheroids were formed after 2D culture of OPCs for 2 days in a hypoxic environment. Otic organoids were generated by 3D culture of otic spheroids under hypoxic conditions for 5 days and normoxic conditions for a further 30 days or more. The protein expression profile, morphological characteristics, and electrophysiological properties of SGN-like cells in otic organoids were similar to those of primary SGNs. Live-cell imaging of AAV-syn-EGFP-labeled neurons demonstrated temporal changes in cell morphology and revealed the toxic effects of ouabain (which causes SGN-specific damage in animal experiments) and cisplatin (a chemotherapeutic drug with ototoxic adverse effects). Furthermore, a cyclin-dependent kinase-2 inhibitor suppressed the toxic actions of cisplatin on SGN-like cells in otic organoids. The otic organoid described here is a candidate novel drug screening system and could be used to identify drugs for the prevention of cisplatin-induced neuropathy.
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Affiliation(s)
- Sho Kurihara
- Division of Regenerative Medicine, The Jikei University School of Medicine, 3-25-8 Nishishimbashi Minato-ku, Tokyo, Japan
- Department of Otorhinolaryngology, The Jikei University School of Medicine, 3-25-8 Nishishimbashi Minato-ku, Tokyo, Japan
| | - Masato Fujioka
- Department of Otorhinolaryngology, Head and Neck Surgery, Keio University School of Medicine, 35 Shinanomachi Shinjuku-ku, Tokyo, Japan
| | - Motoki Hirabayashi
- Division of Regenerative Medicine, The Jikei University School of Medicine, 3-25-8 Nishishimbashi Minato-ku, Tokyo, Japan
- Department of Otorhinolaryngology, The Jikei University School of Medicine, 3-25-8 Nishishimbashi Minato-ku, Tokyo, Japan
| | - Tomohiko Yoshida
- Division of Regenerative Medicine, The Jikei University School of Medicine, 3-25-8 Nishishimbashi Minato-ku, Tokyo, Japan
- Department of Otorhinolaryngology, The Jikei University School of Medicine, 3-25-8 Nishishimbashi Minato-ku, Tokyo, Japan
| | - Makoto Hosoya
- Department of Otorhinolaryngology, Head and Neck Surgery, Keio University School of Medicine, 35 Shinanomachi Shinjuku-ku, Tokyo, Japan
| | - Masashi Nagase
- Department of Neuroscience, The Jikei University School of Medicine, 3-25-8 Nishishimbashi Minato-ku, Tokyo, Japan
| | - Fusao Kato
- Department of Neuroscience, The Jikei University School of Medicine, 3-25-8 Nishishimbashi Minato-ku, Tokyo, Japan
| | - Kaoru Ogawa
- Department of Otorhinolaryngology, Head and Neck Surgery, Keio University School of Medicine, 35 Shinanomachi Shinjuku-ku, Tokyo, Japan
| | - Hideyuki Okano
- Department of Physiology, Keio University School of Medicine, 35 Shinanomachi Shinjuku-ku, Tokyo, Japan
| | - Hiromi Kojima
- Department of Otorhinolaryngology, The Jikei University School of Medicine, 3-25-8 Nishishimbashi Minato-ku, Tokyo, Japan
| | - Hirotaka James Okano
- Division of Regenerative Medicine, The Jikei University School of Medicine, 3-25-8 Nishishimbashi Minato-ku, Tokyo, Japan
- Corresponding author: Hirotaka James Okano, MD, PhD, Division of Regenerative Medicine, The Jikei University School of Medicine, 3-19-18 Nishishimbashi Minato-ku, Tokyo 105-8471, Japan. Tel: +81-3-3433-1111; Fax: +81-3-3578-9208;
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5
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Wu CC, Brugeaud A, Seist R, Lin HC, Yeh WH, Petrillo M, Coppola G, Edge ASB, Stankovic KM. Altered expression of genes regulating inflammation and synaptogenesis during regrowth of afferent neurons to cochlear hair cells. PLoS One 2020; 15:e0238578. [PMID: 33001981 PMCID: PMC7529247 DOI: 10.1371/journal.pone.0238578] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Accepted: 08/19/2020] [Indexed: 12/20/2022] Open
Abstract
The spiral ganglion neurons constitute the primary connection between auditory hair cells and the brain. The spiral ganglion afferent fibers and their synapse with hair cells do not regenerate to any significant degree in adult mammalian ears after damage. We have investigated gene expression changes after kainate-induced disruption of the synapses in a neonatal cochlear explant model in which peripheral fibers and the afferent synapse do regenerate. We compared gene expression early after damage, during regeneration of the fibers and synapses, and after completion of in vitro regeneration. These analyses revealed a total of 2.5% differentially regulated transcripts (588 out of 24,000) based on a threshold of p<0.005. Inflammatory response genes as well as genes involved in regeneration of neural circuits were upregulated in the spiral ganglion neurons and organ of Corti, where the hair cells reside. Prominent genes upregulated at several time points included genes with roles in neurogenesis (Elavl4 and Sox21), neural outgrowth (Ntrk3 and Ppp1r1c), axonal guidance (Rgmb and Sema7a), synaptogenesis (Nlgn2 and Psd2), and synaptic vesicular function (Syt8 and Syn1). Immunohistochemical and in situ hybridization analysis of genes that had not previously been described in the cochlea confirmed their cochlear expression. The time course of expression of these genes suggests that kainate treatment resulted in a two-phase response in spiral ganglion neurons: an acute response consistent with inflammation, followed by an upregulation of neural regeneration genes. Identification of the genes activated during regeneration of these fibers suggests candidates that could be targeted to enhance regeneration in adult ears.
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Affiliation(s)
- Chen-Chi Wu
- Eaton Peabody Laboratories and Department of Otolaryngology—Head and Neck Surgery, Massachusetts Eye and Ear, Boston, Massachusetts, United States of America
- Department of Otolaryngology—Head and Neck Surgery, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Aurore Brugeaud
- Eaton Peabody Laboratories and Department of Otolaryngology—Head and Neck Surgery, Massachusetts Eye and Ear, Boston, Massachusetts, United States of America
- Department of Otolaryngology—Head and Neck Surgery, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Richard Seist
- Eaton Peabody Laboratories and Department of Otolaryngology—Head and Neck Surgery, Massachusetts Eye and Ear, Boston, Massachusetts, United States of America
- Department of Otolaryngology—Head and Neck Surgery, Harvard Medical School, Boston, Massachusetts, United States of America
- Department of Otorhinolaryngology-Head and Neck Surgery, Paracelsus Medical University, Salzburg, Austria
| | - Hsiao-Chun Lin
- Eaton Peabody Laboratories and Department of Otolaryngology—Head and Neck Surgery, Massachusetts Eye and Ear, Boston, Massachusetts, United States of America
- Department of Otolaryngology—Head and Neck Surgery, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Wei-Hsi Yeh
- Eaton Peabody Laboratories and Department of Otolaryngology—Head and Neck Surgery, Massachusetts Eye and Ear, Boston, Massachusetts, United States of America
- Department of Otolaryngology—Head and Neck Surgery, Harvard Medical School, Boston, Massachusetts, United States of America
- Program in Speech and Hearing Bioscience and Technology, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Marco Petrillo
- Eaton Peabody Laboratories and Department of Otolaryngology—Head and Neck Surgery, Massachusetts Eye and Ear, Boston, Massachusetts, United States of America
- Department of Otolaryngology—Head and Neck Surgery, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Giovanni Coppola
- Program in Neurogenetics, Department of Neurology, University of California Los Angeles, Los Angeles, California, United States of America
| | - Albert S. B. Edge
- Eaton Peabody Laboratories and Department of Otolaryngology—Head and Neck Surgery, Massachusetts Eye and Ear, Boston, Massachusetts, United States of America
- Department of Otolaryngology—Head and Neck Surgery, Harvard Medical School, Boston, Massachusetts, United States of America
- Program in Speech and Hearing Bioscience and Technology, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Konstantina M. Stankovic
- Eaton Peabody Laboratories and Department of Otolaryngology—Head and Neck Surgery, Massachusetts Eye and Ear, Boston, Massachusetts, United States of America
- Department of Otolaryngology—Head and Neck Surgery, Harvard Medical School, Boston, Massachusetts, United States of America
- Program in Speech and Hearing Bioscience and Technology, Harvard Medical School, Boston, Massachusetts, United States of America
- Harvard Program in Therapeutic Science, Harvard Medical School, Boston, Massachusetts, United States of America
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Tang PC, Hashino E, Nelson RF. Progress in Modeling and Targeting Inner Ear Disorders with Pluripotent Stem Cells. Stem Cell Reports 2020; 14:996-1008. [PMID: 32442531 PMCID: PMC7355141 DOI: 10.1016/j.stemcr.2020.04.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 04/21/2020] [Accepted: 04/22/2020] [Indexed: 12/12/2022] Open
Abstract
Sensorineural hearing loss and vestibular dysfunction are caused by damage to neurons and mechanosensitive hair cells, which do not regenerate to any clinically relevant extent in humans. Several protocols have been devised to direct pluripotent stem cells (PSCs) into inner ear hair cells and neurons, which display many properties of their native counterparts. The efficiency, reproducibility, and scalability of these protocols are enhanced by incorporating knowledge of inner ear development. Modeling human diseases in vitro through genetic manipulation of PSCs is already feasible, thereby permitting the elucidation of mechanistic understandings of a wide array of disease etiologies. Early studies on transplantation of PSC-derived otic progenitors have been successful in certain animal models, yet restoration of function and long-term cell survival remain unrealized. Through further research, PSC-based approaches will continue to revolutionize our understanding of inner ear biology and contribute to the development of therapeutic treatments for inner ear disorders.
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Affiliation(s)
- Pei-Ciao Tang
- Department of Otolaryngology-Head and Neck Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Eri Hashino
- Department of Otolaryngology-Head and Neck Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA; Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Rick F Nelson
- Department of Otolaryngology-Head and Neck Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA.
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Van De Water TR. Historical Aspects of Gene Therapy and Stem Cell Therapy in the Treatment of Hearing and Balance Disorder. Anat Rec (Hoboken) 2020; 303:390-407. [DOI: 10.1002/ar.24332] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Revised: 11/18/2019] [Accepted: 11/22/2019] [Indexed: 12/20/2022]
Affiliation(s)
- Thomas R. Van De Water
- Cochlear Implant Research Program, Department of Otolaryngology, University of Miami Ear InstituteUniversity of Miami Miller School of Medicine Miami Florida
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8
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Organotypic Cocultures of Human Pluripotent Stem Cell Derived-Neurons with Mammalian Inner Ear Hair Cells and Cochlear Nucleus Slices. Stem Cells Int 2019; 2019:8419493. [PMID: 31827535 PMCID: PMC6886346 DOI: 10.1155/2019/8419493] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Revised: 08/29/2019] [Accepted: 09/21/2019] [Indexed: 11/27/2022] Open
Abstract
Stem cells have been touted as a source of potential replacement neurons for inner ear degeneration for almost two decades now; yet to date, there are few studies describing the use of human pluripotent stem cells (hPSCs) for this purpose. If stem cell therapies are to be used clinically, it is critical to validate the usefulness of hPSC lines in vitro and in vivo. Here, we present the first quantitative evidence that differentiated hPSC-derived neurons that innervate both the inner ear hair cells and cochlear nucleus neurons in coculture, with significantly more new synaptic contacts formed on target cell types. Nascent contacts between stem cells and hair cells were immunopositive for both synapsin I and VGLUT1, closely resembling expression of these puncta in endogenous postnatal auditory neurons and control cocultures. When hPSCs were cocultured with cochlear nucleus brainstem slice, significantly greater numbers of VGLUT1 puncta were observed in comparison to slice alone. New VGLUT1 puncta in cocultures with cochlear nucleus slice were not significantly different in size, only in quantity. This experimentation describes new coculture models for assessing auditory regeneration using well-characterised hPSC-derived neurons and highlights useful methods to quantify the extent of innervation on different cell types in the inner ear and brainstem.
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9
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Stem-cell therapy for hearing loss: are we there yet? Braz J Otorhinolaryngol 2019; 85:520-529. [PMID: 31186186 PMCID: PMC9443044 DOI: 10.1016/j.bjorl.2019.04.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Accepted: 04/28/2019] [Indexed: 12/04/2022] Open
Abstract
Introduction Mammalian hair cells and auditory neurons do not show regenerative capacity. Hence, damage to these cell types is permanent and leads to hearing loss. However, there is no treatment that re-establishes auditory function. Regenerative therapies using stem cells represent a promising alternative. Objective This article aims to review the current literature about the main types of stem cells with potential for application in cell therapy for sensorineural hearing loss, the most relevant experiments already performed in animals, as well as the advances that have been recently made in the field. Methods Research included the databases PubMed/MEDLINE, Web of Science, Science Direct and SciELO, as well as gray literature. Search strategy included the following main terms: “stem cells”, “hair cells” and “auditory neurons”. Additionally, the main terms were combined with the following secondary terms: “mesenchymal”, “iPS”, “inner ear”, “auditory”. The research was conducted independently by three researchers. Results Differentiation of stem cells into hair cells and auditory neurons has a high success rate, reaching up to 82% for the first and 100% for the latter. Remarkably, these differentiated cells are able to interact with hair cells and auditory neurons of cochlear explants through formation of new synapses. When transplanted into the cochlea of animals with hearing loss, auditory restoration has been documented to date only in deafferented animals. Conclusion Advances have been more prominent in cases of auditory neuropathy, since partial improvement of auditory nerve conditions through cell-based therapy may increase the number of patients who can successfully receive cochlear implants.
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Ogier JM, Burt RA, Drury HR, Lim R, Nayagam BA. Organotypic Culture of Neonatal Murine Inner Ear Explants. Front Cell Neurosci 2019; 13:170. [PMID: 31130846 PMCID: PMC6509234 DOI: 10.3389/fncel.2019.00170] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2018] [Accepted: 04/11/2019] [Indexed: 01/08/2023] Open
Abstract
The inner ear is a complex organ containing highly specialised cell types and structures that are critical for sensing sound and movement. In vivo, the inner ear is difficult to study due to the osseous nature of the otic capsule and its encapsulation within an intricate bony labyrinth. As such, mammalian inner ear explants are an invaluable tool for the study and manipulation of the complex intercellular connections, structures, and cell types within this specialised organ. The greatest strength of this technique is that the complete organ of Corti, or peripheral vestibular organs including hair cells, supporting cells and accompanying neurons, is maintained in its in situ form. The greatest weakness of in vitro hair cell preparations is the short time frame in which the explanted tissue remains viable. Yet, cochlear explants have proven to be an excellent experimental model for understanding the fundamental aspects of auditory biology, substantiated by their use for over 40 years. In this protocol, we present a modernised inner ear explant technique that employs organotypic cell culture inserts and serum free media. This approach decreases the likelihood of explant damage by eliminating the need for adhesive substances. Serum free media also restricts excessive cellular outgrowth and inter-experimental variability, both of which are side effects of exogenous serum addition to cell cultures. The protocol described can be applied to culture both cochlear and vestibular explants from various mammals. Example outcomes are demonstrated by immunohistochemistry, hair cell quantification, and electrophysiological recordings to validate the versatility and viability of the protocol.
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Affiliation(s)
- Jacqueline M. Ogier
- Department of Genetics, The Murdoch Children's Research Institute, Parkville, VIC, Australia
- Department of Paediatrics, The University of Melbourne, Parkville, VIC, Australia
| | - Rachel A. Burt
- Department of Genetics, The Murdoch Children's Research Institute, Parkville, VIC, Australia
- Department of Paediatrics, The University of Melbourne, Parkville, VIC, Australia
- Department of Genetics, The University of Melbourne, Parkville, VIC, Australia
| | - Hannah R. Drury
- School of Biomedical Sciences and Pharmacy, The University of Newcastle, Callaghan, NSW, Australia
| | - Rebecca Lim
- School of Biomedical Sciences and Pharmacy, The University of Newcastle, Callaghan, NSW, Australia
| | - Bryony A. Nayagam
- Department of Audiology and Speech Pathology, The University of Melbourne, Parkville, VIC, Australia
- The Bionics Institute, East Melbourne, VIC, Australia
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Meas SJ, Zhang CL, Dabdoub A. Reprogramming Glia Into Neurons in the Peripheral Auditory System as a Solution for Sensorineural Hearing Loss: Lessons From the Central Nervous System. Front Mol Neurosci 2018; 11:77. [PMID: 29593497 PMCID: PMC5861218 DOI: 10.3389/fnmol.2018.00077] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2018] [Accepted: 02/26/2018] [Indexed: 12/12/2022] Open
Abstract
Disabling hearing loss affects over 5% of the world’s population and impacts the lives of individuals from all age groups. Within the next three decades, the worldwide incidence of hearing impairment is expected to double. Since a leading cause of hearing loss is the degeneration of primary auditory neurons (PANs), the sensory neurons of the auditory system that receive input from mechanosensory hair cells in the cochlea, it may be possible to restore hearing by regenerating PANs. A direct reprogramming approach can be used to convert the resident spiral ganglion glial cells into induced neurons to restore hearing. This review summarizes recent advances in reprogramming glia in the CNS to suggest future steps for regenerating the peripheral auditory system. In the coming years, direct reprogramming of spiral ganglion glial cells has the potential to become one of the leading biological strategies to treat hearing impairment.
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Affiliation(s)
- Steven J Meas
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada.,Biological Sciences, Sunnybrook Research Institute, Toronto, ON, Canada
| | - Chun-Li Zhang
- Department of Molecular Biology, The University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Alain Dabdoub
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada.,Biological Sciences, Sunnybrook Research Institute, Toronto, ON, Canada.,Department of Otolaryngology - Head & Neck Surgery, University of Toronto, Toronto, ON, Canada
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12
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Regenerative medicine in hearing recovery. Cytotherapy 2017; 19:909-915. [DOI: 10.1016/j.jcyt.2017.04.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Revised: 03/24/2017] [Accepted: 04/21/2017] [Indexed: 12/20/2022]
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Revuelta M, Santaolalla F, Arteaga O, Alvarez A, Sánchez-del-Rey A, Hilario E. Recent advances in cochlear hair cell regeneration-A promising opportunity for the treatment of age-related hearing loss. Ageing Res Rev 2017; 36:149-155. [PMID: 28414155 DOI: 10.1016/j.arr.2017.04.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2017] [Revised: 04/05/2017] [Accepted: 04/10/2017] [Indexed: 01/22/2023]
Abstract
The objective of this paper is to review current information regarding the treatment of age-related hearing loss by using cochlear hair cell regeneration. Recent advances in the regeneration of the inner ear, including the usefulness of stem cells, are also presented. Based on the current literature, cochlear cell regeneration may well be possible in the short term and cochlear gene therapy may also be useful for the treatment of hearing loss associated with ageing. The present review provide further insight into the pathogenesis of Inner Ear senescence and aged-related hearing loss and facilitate the development of therapeutic strategies to repair hair cells damaged by ageing. More research will be needed in order to translate them into an effective treatment for deafness linked to cochlear senescence in humans.
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14
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Matsuoka AJ, Morrissey ZD, Zhang C, Homma K, Belmadani A, Miller CA, Chadly DM, Kobayashi S, Edelbrock AN, Tanaka‐Matakatsu M, Whitlon DS, Lyass L, McGuire TL, Stupp SI, Kessler JA. Directed Differentiation of Human Embryonic Stem Cells Toward Placode-Derived Spiral Ganglion-Like Sensory Neurons. Stem Cells Transl Med 2017; 6:923-936. [PMID: 28186679 PMCID: PMC5442760 DOI: 10.1002/sctm.16-0032] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2016] [Revised: 08/31/2016] [Accepted: 10/19/2016] [Indexed: 12/15/2022] Open
Abstract
The ability to generate spiral ganglion neurons (SGNs) from stem cells is a necessary prerequisite for development of cell-replacement therapies for sensorineural hearing loss. We present a protocol that directs human embryonic stem cells (hESCs) toward a purified population of otic neuronal progenitors (ONPs) and SGN-like cells. Between 82% and 95% of these cells express SGN molecular markers, they preferentially extend neurites to the cochlear nucleus rather than nonauditory nuclei, and they generate action potentials. The protocol follows an in vitro stepwise recapitulation of developmental events inherent to normal differentiation of hESCs into SGNs, resulting in efficient sequential generation of nonneuronal ectoderm, preplacodal ectoderm, early prosensory ONPs, late ONPs, and cells with cellular and molecular characteristics of human SGNs. We thus describe the sequential signaling pathways that generate the early and later lineage species in the human SGN lineage, thereby better describing key developmental processes. The results indicate that our protocol generates cells that closely replicate the phenotypic characteristics of human SGNs, advancing the process of guiding hESCs to states serving inner-ear cell-replacement therapies and possible next-generation hybrid auditory prostheses. © Stem Cells Translational Medicine 2017;6:923-936.
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Affiliation(s)
- Akihiro J. Matsuoka
- Department of Otolaryngology and Head and Neck SurgeryChicagoILUSA
- Department of Communication Sciences and DisordersChicagoILUSA
- Knowles Hearing CenterChicagoILUSA
| | | | - Chaoying Zhang
- Department of Otolaryngology and Head and Neck SurgeryChicagoILUSA
| | - Kazuaki Homma
- Department of Otolaryngology and Head and Neck SurgeryChicagoILUSA
- Knowles Hearing CenterChicagoILUSA
| | - Abdelhak Belmadani
- Department of Molecular Pharmacology and Biological ChemistryChicagoILUSA
| | | | - Duncan M. Chadly
- Department of Otolaryngology and Head and Neck SurgeryChicagoILUSA
| | - Shun Kobayashi
- Department of Otolaryngology and Head and Neck SurgeryChicagoILUSA
| | | | | | - Donna S. Whitlon
- Department of Otolaryngology and Head and Neck SurgeryChicagoILUSA
- Knowles Hearing CenterChicagoILUSA
| | - Ljuba Lyass
- Department of Biomedical EngineeringChicagoILUSA
| | | | - Samuel I. Stupp
- Department of MedicineChicagoILUSA
- Department of Biomedical EngineeringChicagoILUSA
- Simpson Querrey Institute for BioNanotechnologyChicagoILUSA
- Department of ChemistryNorthwestern University
- Department of Materials Science & EngineeringNorthwestern University
| | - John A. Kessler
- Department of NeurologyFeinberg School of Medicine, Northwestern UniversityChicagoILUSA
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15
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Taura A, Nakashima N, Ohnishi H, Nakagawa T, Funabiki K, Ito J, Omori K. Regenerative therapy for vestibular disorders using human induced pluripotent stem cells (iPSCs): neural differentiation of human iPSC-derived neural stem cells after in vitro transplantation into mouse vestibular epithelia. Acta Otolaryngol 2016; 136:999-1005. [PMID: 27196942 DOI: 10.1080/00016489.2016.1183169] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
OBJECTIVES Vestibular ganglion cells, which convey sense of motion from vestibular hair cells to the brainstem, are known to degenerate with aging and after vestibular neuritis. Thus, regeneration of vestibular ganglion cells is important to aid in the recovery of balance for associated disorders. METHODS The present study derived hNSCs from induced pluripotent stem cells (iPSCs) and transplanted these cells into mouse utricle tissues. After a 7-day co-culture period, histological and electrophysiological examinations of transplanted hNSCs were performed. RESULTS Injected hNSC-derived cells produced elongated axon-like structures within the utricle tissue that made contact with vestibular hair cells. A proportion of hNSC-derived cells showed spontaneous firing activities, similar to those observed in cultured mouse vestibular ganglion cells. However, hNSC-derived cells around the mouse utricle persisted as immature neurons or occasionally differentiated into putative astrocytes. Moreover, electrophysiological examination showed hNSC-derived cells around utricles did not exhibit any obvious spontaneous firing activities. CONCLUSIONS Injected human neural stem cells (hNSCs) showed signs of morphological maturation including reconnection to denervated hair cells and partial physiological maturation, suggesting hNSC-derived cells possibly differentiated into neurons.
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Affiliation(s)
- Akiko Taura
- Department of Otolaryngology, Head and Neck Surgery, Kyoto University Hospital/Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Noriyuki Nakashima
- Department of Physiology, Kurume University Hospital/Graduate School of Medicine, Kurume University, Kurume, Japan
| | - Hiroe Ohnishi
- Department of Otolaryngology, Head and Neck Surgery, Kyoto University Hospital/Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Takayuki Nakagawa
- Department of Otolaryngology, Head and Neck Surgery, Kyoto University Hospital/Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Kazuo Funabiki
- Institute of Biomedical Research and Innovation, Kobe, Japan
| | - Juichi Ito
- Department of Otolaryngology, Head and Neck Surgery, Kyoto University Hospital/Graduate School of Medicine, Kyoto University, Kyoto, Japan
- Shiga Medical Center Research Institute, Shiga, Japan
| | - Koichi Omori
- Department of Otolaryngology, Head and Neck Surgery, Kyoto University Hospital/Graduate School of Medicine, Kyoto University, Kyoto, Japan
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16
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Enriched retinal ganglion cells derived from human embryonic stem cells. Sci Rep 2016; 6:30552. [PMID: 27506453 PMCID: PMC4978994 DOI: 10.1038/srep30552] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2015] [Accepted: 07/04/2016] [Indexed: 12/21/2022] Open
Abstract
Optic neuropathies are characterised by a loss of retinal ganglion cells (RGCs) that lead to vision impairment. Development of cell therapy requires a better understanding of the signals that direct stem cells into RGCs. Human embryonic stem cells (hESCs) represent an unlimited cellular source for generation of human RGCs in vitro. In this study, we present a 45-day protocol that utilises magnetic activated cell sorting to generate enriched population of RGCs via stepwise retinal differentiation using hESCs. We performed an extensive characterization of these stem cell-derived RGCs by examining the gene and protein expressions of a panel of neural/RGC markers. Furthermore, whole transcriptome analysis demonstrated similarity of the hESC-derived RGCs to human adult RGCs. The enriched hESC-RGCs possess long axons, functional electrophysiological profiles and axonal transport of mitochondria, suggestive of maturity. In summary, this RGC differentiation protocol can generate an enriched population of functional RGCs from hESCs, allowing future studies on disease modeling of optic neuropathies and development of cell therapies.
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17
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Kwan KY. Single-Cell Transcriptome Analysis of Developing and Regenerating Spiral Ganglion Neurons. ACTA ACUST UNITED AC 2016; 2:211-220. [PMID: 28758056 DOI: 10.1007/s40495-016-0064-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The spiral ganglion neurons (SGNs) of the cochlea are essential for our ability to hear. SGN loss after exposure to ototoxic drugs or loud noise results in hearing loss. Pluripotent stem cell-derived and endogenous progenitor cell types have the potential to become SGNs and are cellular foundations for replacement therapies. Repurposing transcriptional regulatory networks to promote SGN differentiation from progenitor cells is a strategy for regeneration. Advances in the Fludigm C1 workflow or Drop-seq allow sequencing of single cell transcriptomes to reveal variability between cells. During differentiation, the individual transcriptomes obtained from single-cell RNA-seq can be exploited to identify different cellular states. Pseudotemporal ordering of transcriptomes describes the differentiation trajectory, allows monitoring of transcriptional changes and determines molecular barriers that prevent the progression of progenitors into SGNs. Analysis of single cell transcriptomes will help develop novel strategies for guiding efficient SGN regeneration.
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Affiliation(s)
- Kelvin Y Kwan
- Department of Cell Biology & Neuroscience, Rutgers University, Piscataway, NJ 08854, USA.,Stem Cell Research Center and Keck Center for Collaborative Neuroscience, Rutgers University, Piscataway, NJ 08854, USA
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18
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Innervation of Cochlear Hair Cells by Human Induced Pluripotent Stem Cell-Derived Neurons In Vitro. Stem Cells Int 2016; 2016:1781202. [PMID: 26966437 PMCID: PMC4761396 DOI: 10.1155/2016/1781202] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Accepted: 12/31/2015] [Indexed: 01/09/2023] Open
Abstract
Induced pluripotent stem cells (iPSCs) may serve as an autologous source of replacement neurons in the injured cochlea, if they can be successfully differentiated and reconnected with residual elements in the damaged auditory system. Here, we explored the potential of hiPSC-derived neurons to innervate early postnatal hair cells, using established in vitro assays. We compared two hiPSC lines against a well-characterized hESC line. After ten days' coculture in vitro, hiPSC-derived neural processes contacted inner and outer hair cells in whole cochlear explant cultures. Neural processes from hiPSC-derived neurons also made contact with hair cells in denervated sensory epithelia explants and expressed synapsin at these points of contact. Interestingly, hiPSC-derived neurons cocultured with hair cells at an early stage of differentiation formed synapses with a higher number of hair cells, compared to hiPSC-derived neurons cocultured at a later stage of differentiation. Notable differences in the innervation potentials of the hiPSC-derived neurons were also observed and variations existed between the hiPSC lines in their innervation efficiencies. Collectively, these data illustrate the promise of hiPSCs for auditory neuron replacement and highlight the need to develop methods to mitigate variabilities observed amongst hiPSC lines, in order to achieve reliable clinical improvements for patients.
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19
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Gillespie LN, Richardson RT, Nayagam BA, Wise AK. Treating hearing disorders with cell and gene therapy. J Neural Eng 2015; 11:065001. [PMID: 25420002 DOI: 10.1088/1741-2560/11/6/065001] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Hearing loss is an increasing problem for a substantial number of people and, with an aging population, the incidence and severity of hearing loss will become more significant over time. There are very few therapies currently available to treat hearing loss, and so the development of new therapeutic strategies for hearing impaired individuals is of paramount importance to address this unmet clinical need. Most forms of hearing loss are progressive in nature and therefore an opportunity exists to develop novel therapeutic approaches to slow or halt hearing loss progression, or even repair or replace lost hearing function. Numerous emerging technologies have potential as therapeutic options. This paper details the potential of cell- and gene-based therapies to provide therapeutic agents to protect sensory and neural cells from various insults known to cause hearing loss; explores the potential of replacing lost sensory and nerve cells using gene and stem cell therapy; and describes the considerations for clinical translation and the challenges that need to be overcome.
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20
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Ohnishi H, Kawasaki T, Deguchi T, Yuba S. Generation of Xeroderma Pigmentosum-A Patient-Derived Induced Pluripotent Stem Cell Line for Use As Future Disease Model. Cell Reprogram 2015; 17:268-74. [PMID: 26090552 DOI: 10.1089/cell.2014.0104] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Xeroderma pigmentosum group A (XP-A) is a genetic disorder in which there is an abnormality in nucleotide excision repair that causes hypersensitivity to sunlight and multiple skin cancers. The development of central and peripheral neurological disorders not correlated to ultraviolet light exposure is associated with XP-A. The genes responsible for XP-A have been identified and a XPA knockout mouse has been generated. These knockout mice exhibit cutaneous symptoms, but they do not show neurological disorders. The mechanism of pathogenesis of neurological disorders is still unclear and therapeutic methods have not been established. Therefore, we generated XP-A patient-derived human induced pluripotent stem cells (XPA-iPSCs) to produce in vitro models of neurological disorders. We obtained iPSC lines from fibroblasts of two patients carrying different mutations. Drugs screened using XPA-iPSC lines can be helpful for treating XP-A patients in Japan. Additionally, we revealed that these iPSCs have the potential to differentiate into neural lineage cells, including dopaminergic neurons, which decrease in XP-A patients. Our results indicate that expression of the normal XPA gene without mutations is not required for generation of iPSCs and differentiation of iPSCs into neural lineage cells. XPA-iPSCs may become useful models that clarify our understanding of neurological pathogenesis and help to establish therapeutic methods.
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Affiliation(s)
- Hiroe Ohnishi
- 1 Tissue Engineering Research Group, Health Research Institute, National Institute of Advanced Industrial Science and Technology (AIST) , Amagasaki, Hyogo 661-0974, Japan .,4 Present address: Department of Otolaryngology, Graduate School of Medicine, Kyoto University , Kyoto 606-8507, Japan
| | - Takashi Kawasaki
- 2 Functional Biomolecular Research Group, Health Research Institute, National Institute of Advanced Industrial Science and Technology (AIST) , Amagasaki, Hyogo 661-0974, Japan
| | - Tomonori Deguchi
- 3 Stress Signal Research Group, Health Research Institute, National Institute of Advanced Industrial Science and Technology (AIST) , Ikeda, Osaka 563-8577, Japan
| | - Shunsuke Yuba
- 1 Tissue Engineering Research Group, Health Research Institute, National Institute of Advanced Industrial Science and Technology (AIST) , Amagasaki, Hyogo 661-0974, Japan
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21
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22
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Using Pluripotent Stem Cells and Their Progeny as an In VitroModel to Assess (Developmental) Neurotoxicity. METHODS AND PRINCIPLES IN MEDICINAL CHEMISTRY 2014. [DOI: 10.1002/9783527674183.ch13] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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23
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Gunewardene N, Bergen NV, Crombie D, Needham K, Dottori M, Nayagam BA. Directing human induced pluripotent stem cells into a neurosensory lineage for auditory neuron replacement. Biores Open Access 2014; 3:162-75. [PMID: 25126480 PMCID: PMC4120935 DOI: 10.1089/biores.2014.0019] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Emerging therapies for sensorineural hearing loss include replacing damaged auditory neurons (ANs) using stem cells. Ultimately, it is important that these replacement cells can be patient-matched to avoid immunorejection. As human induced pluripotent stem cells (hiPSCs) can be obtained directly from the patient, they offer an opportunity to generate patient-matched neurons for transplantation. Here, we used an established neural induction protocol to differentiate two hiPSC lines (iPS1 and iPS2) and one human embryonic stem cell line (hESC; H9) toward a neurosensory lineage in vitro. Immunocytochemistry and qRT-PCR were used to analyze the expression of key markers involved in AN development at defined time points of differentiation. The hiPSC- and hESC-derived neurosensory progenitors expressed the dorsal hindbrain marker (PAX7), otic placodal marker (PAX2), proneurosensory marker (SOX2), ganglion neuronal markers (NEUROD1, BRN3A, ISLET1, ßIII-tubulin, Neurofilament kDa 160), and sensory AN markers (GATA3 and VGLUT1) over the time course examined. The hiPSC- and hESC-derived neurosensory progenitors had the highest expression levels of the sensory neural markers at 35 days in vitro. Furthermore, the neurons generated from this assay were found to be electrically active. While all cell lines analyzed produced functional neurosensory-like progenitors, variabilities in the levels of marker expression were observed between hiPSC lines and within samples of the same cell line, when compared with the hESC controls. Overall, these findings indicate that this neural assay was capable of differentiating hiPSCs toward a neurosensory lineage but emphasize the need for improving the consistency in the differentiation of hiPSCs into the required lineages.
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Affiliation(s)
- Niliksha Gunewardene
- Department of Otolaryngology, University of Melbourne , East Melbourne, Victoria, Australia
| | - Nicole Van Bergen
- Centre for Eye Research Australia, University of Melbourne , East Melbourne, Victoria, Australia
| | - Duncan Crombie
- Centre for Eye Research Australia, University of Melbourne , East Melbourne, Victoria, Australia
| | - Karina Needham
- Department of Otolaryngology, University of Melbourne , East Melbourne, Victoria, Australia
| | - Mirella Dottori
- Centre for Neural Engineering, University of Melbourne , Parkville, Victoria, Australia
| | - Bryony A Nayagam
- Centre for Eye Research Australia, University of Melbourne , East Melbourne, Victoria, Australia . ; Department of Audiology and Speech Pathology, University of Melbourne , Parkville, Victoria, Australia . ; Bionics Institute, University of Melbourne , East Melbourne, Victoria, Australia
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24
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Needham K, Hyakumura T, Gunewardene N, Dottori M, Nayagam BA. Electrophysiological properties of neurosensory progenitors derived from human embryonic stem cells. Stem Cell Res 2013; 12:241-9. [PMID: 24280418 DOI: 10.1016/j.scr.2013.10.011] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/06/2013] [Revised: 10/30/2013] [Accepted: 10/30/2013] [Indexed: 01/19/2023] Open
Abstract
In severe cases of sensorineural hearing loss where the numbers of auditory neurons are significantly depleted, stem cell-derived neurons may provide a potential source of replacement cells. The success of such a therapy relies upon producing a population of functional neurons from stem cells, to enable precise encoding of sound information to the brainstem. Using our established differentiation assay to produce sensory neurons from human stem cells, patch-clamp recordings indicated that all neurons examined generated action potentials and displayed both transient sodium and sustained potassium currents. Stem cell-derived neurons reliably entrained to stimuli up to 20 pulses per second (pps), with 50% entrainment at 50 pps. A comparison with cultured primary auditory neurons indicated similar firing precision during low-frequency stimuli, but significant differences after 50 pps due to differences in action potential latency and width. The firing properties of stem cell-derived neurons were also considered relative to time in culture (31-56 days) and revealed no change in resting membrane potential, threshold or firing latency over time. Thus, while stem cell-derived neurons did not entrain to high frequency stimulation as effectively as mammalian auditory neurons, their electrical phenotype was stable in culture and consistent with that reported for embryonic auditory neurons.
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Affiliation(s)
- Karina Needham
- Department of Otolaryngology, University of Melbourne, Royal Victorian Eye and Ear Hospital, Level 2, 32 Gisborne Street, East Melbourne, VIC 3002, Australia; Department of Medicine, St Vincent's Hospital, University of Melbourne, Level 4, Clinical Sciences Building, 29 Regent Street, Fitzroy, VIC 3065, Australia.
| | - Tomoko Hyakumura
- Department of Otolaryngology, University of Melbourne, Royal Victorian Eye and Ear Hospital, Level 2, 32 Gisborne Street, East Melbourne, VIC 3002, Australia.
| | - Niliksha Gunewardene
- Department of Otolaryngology, University of Melbourne, Royal Victorian Eye and Ear Hospital, Level 2, 32 Gisborne Street, East Melbourne, VIC 3002, Australia.
| | - Mirella Dottori
- Centre for Neural Engineering, NICTA, University of Melbourne, 203 Bouverie Street, Parkville, VIC 3010, Australia.
| | - Bryony A Nayagam
- Department of Otolaryngology, University of Melbourne, Royal Victorian Eye and Ear Hospital, Level 2, 32 Gisborne Street, East Melbourne, VIC 3002, Australia; Department of Audiology and Speech Pathology, University of Melbourne, 550 Swanston Street, Parkville, VIC 3010, Australia; Bionics Institute, 384-388 Albert Street, East Melbourne, VIC 3002, Australia.
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25
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Shi F, Edge ASB. Prospects for replacement of auditory neurons by stem cells. Hear Res 2013; 297:106-12. [PMID: 23370457 DOI: 10.1016/j.heares.2013.01.017] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/16/2012] [Revised: 01/16/2013] [Accepted: 01/18/2013] [Indexed: 02/07/2023]
Abstract
Sensorineural hearing loss is caused by degeneration of hair cells or auditory neurons. Spiral ganglion cells, the primary afferent neurons of the auditory system, are patterned during development and send out projections to hair cells and to the brainstem under the control of largely unknown guidance molecules. The neurons do not regenerate after loss and even damage to their projections tends to be permanent. The genesis of spiral ganglion neurons and their synapses forms a basis for regenerative approaches. In this review we critically present the current experimental findings on auditory neuron replacement. We discuss the latest advances with a focus on (a) exogenous stem cell transplantation into the cochlea for neural replacement, (b) expression of local guidance signals in the cochlea after loss of auditory neurons, (c) the possibility of neural replacement from an endogenous cell source, and (d) functional changes from cell engraftment.
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Affiliation(s)
- Fuxin Shi
- Department of Otology and Laryngology, Harvard Medical School, Boston, MA 02114, USA
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