Innervation of Cochlear Hair Cells by Human Induced Pluripotent Stem Cell-Derived NeuronsIn Vitro

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 establishedin vitroassays. We compared two hiPSC lines against a well-characterized hESC line. After ten days’ coculturein 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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Olivocochlear suppression of outer hair cells in vivo: evidence for combined action of BK and SK2 channels throughout the cochlea

Journal of Neurophysiology ◽

10.1152/jn.00924.2012 ◽

2013 ◽

Vol 109 (6) ◽

pp. 1525-1534 ◽

Cited By ~ 27

Author(s):

Stéphane F. Maison ◽

Sonja J. Pyott ◽

Andrea L. Meredith ◽

M. Charles Liberman

Keyword(s):

Hair Cells ◽

In Vitro Study ◽

Bk Channels ◽

Outer Hair Cells ◽

Cochlear Hair Cells ◽

Α Subunit ◽

Combined Action ◽

Cholinergic Effects

Cholinergic inhibition of cochlear hair cells via olivocochlear (OC)-efferent feedback is mediated by Ca2+ entry through α9-/α10-nicotinic receptors, but the nature of the K+ channels activated by this Ca2+ entry has been debated (Yoshida N, Hequembourg SJ, Atencio CA, Rosowski JJ, Liberman MC. J Neurophysiol 85: 84–88, 2001). A recent in vitro study (Wersinger E, McLean WJ, Fuchs PA, Pyott SJ. PLoS One 5: e13836, 2010) suggests that small-conductance (SK2) channels mediate cholinergic effects in the apical turn, whereas large-conductance (BK) channels mediate basal turn effects. Here, we measure, as a function of cochlear frequency, the magnitude of BK and SK2 expression in outer hair cells and the strength of in vivo OC suppression in BK+/+ mice vs. BK−/− lacking the obligatory α-subunit (Meredith AL, Thorneloe KS, Werner ME, Nelson MT, Aldrich RW. J Biol Chem 279: 36746–36752, 2004). Except at the extreme apical tip, we see immunostaining for both BK and SK2 in BK+/+. Correspondingly, at all testable frequencies (8–45 kHz), we see evidence for both SK2 and BK contributions to OC effects evoked by electrically stimulating the OC bundle: OC-mediated suppression was reduced, but not eliminated, at all frequencies in the BK−/− ears. The suppression remaining in BK nulls was blocked by strychnine, suggesting involvement of α9-/α10-cholinergic receptors, coupled to activation of the remaining SK2 channels.

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Deep learning detects cardiotoxicity in a high-content screen with induced pluripotent stem cell-derived cardiomyocytes

eLife ◽

10.7554/elife.68714 ◽

2021 ◽

Vol 10 ◽

Author(s):

Francis Grafton ◽

Jaclyn Ho ◽

Sara Ranjbarvaziri ◽

Farshad Farshidfar ◽

Anastasiia Budan ◽

...

Keyword(s):

Stem Cell ◽

Deep Learning ◽

Pluripotent Stem Cell ◽

Kinase Inhibitors ◽

Early Stage ◽

Induced Pluripotent Stem Cell ◽

Channel Blockers ◽

Drug Induced ◽

Induced Pluripotent

Drug-induced cardiotoxicity and hepatotoxicity are major causes of drug attrition. To decrease late-stage drug attrition, pharmaceutical and biotechnology industries need to establish biologically relevant models that use phenotypic screening to detect drug-induced toxicity in vitro. In this study, we sought to rapidly detect patterns of cardiotoxicity using high-content image analysis with deep learning and induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs). We screened a library of 1280 bioactive compounds and identified those with potential cardiotoxic liabilities in iPSC-CMs using a single-parameter score based on deep learning. Compounds demonstrating cardiotoxicity in iPSC-CMs included DNA intercalators, ion channel blockers, epidermal growth factor receptor, cyclin-dependent kinase, and multi-kinase inhibitors. We also screened a diverse library of molecules with unknown targets and identified chemical frameworks that show cardiotoxic signal in iPSC-CMs. By using this screening approach during target discovery and lead optimization, we can de-risk early-stage drug discovery. We show that the broad applicability of combining deep learning with iPSC technology is an effective way to interrogate cellular phenotypes and identify drugs that may protect against diseased phenotypes and deleterious mutations.

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Direct SARS-CoV-2 infection of the human inner ear may underlie COVID-19-associated audiovestibular dysfunction

Communications Medicine ◽

10.1038/s43856-021-00044-w ◽

2021 ◽

Vol 1 (1) ◽

Author(s):

Minjin Jeong ◽

Karen E. Ocwieja ◽

Dongjun Han ◽

P. Ashley Wackym ◽

Yichen Zhang ◽

...

Keyword(s):

Inner Ear ◽

Hair Cells ◽

Molecular Mechanisms ◽

Three Dimensional ◽

Induced Pluripotent Stem Cell ◽

In Vitro Models ◽

Cellular Models ◽

Induced Pluripotent ◽

Human Inner Ear

Abstract Background COVID-19 is a pandemic respiratory and vascular disease caused by SARS-CoV-2 virus. There is a growing number of sensory deficits associated with COVID-19 and molecular mechanisms underlying these deficits are incompletely understood. Methods We report a series of ten COVID-19 patients with audiovestibular symptoms such as hearing loss, vestibular dysfunction and tinnitus. To investigate the causal relationship between SARS-CoV-2 and audiovestibular dysfunction, we examine human inner ear tissue, human inner ear in vitro cellular models, and mouse inner ear tissue. Results We demonstrate that adult human inner ear tissue co-expresses the angiotensin-converting enzyme 2 (ACE2) receptor for SARS-CoV-2 virus, and the transmembrane protease serine 2 (TMPRSS2) and FURIN cofactors required for virus entry. Furthermore, hair cells and Schwann cells in explanted human vestibular tissue can be infected by SARS-CoV-2, as demonstrated by confocal microscopy. We establish three human induced pluripotent stem cell (hiPSC)-derived in vitro models of the inner ear for infection: two-dimensional otic prosensory cells (OPCs) and Schwann cell precursors (SCPs), and three-dimensional inner ear organoids. Both OPCs and SCPs express ACE2, TMPRSS2, and FURIN, with lower ACE2 and FURIN expression in SCPs. OPCs are permissive to SARS-CoV-2 infection; lower infection rates exist in isogenic SCPs. The inner ear organoids show that hair cells express ACE2 and are targets for SARS-CoV-2. Conclusions Our results provide mechanistic explanations of audiovestibular dysfunction in COVID-19 patients and introduce hiPSC-derived systems for studying infectious human otologic disease.

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Effects of SERCA and PMCA inhibitors on the survival of rat cochlear hair cells during ischemia in vitro

Physiological Research ◽

10.33549/physiolres.931259 ◽

2008 ◽

pp. 631-638

Author(s):

N Amarjargal ◽

B Mazurek ◽

H Haupt ◽

N Andreeva ◽

J Fuchs ◽

...

Keyword(s):

Hair Cells ◽

Smooth Endoplasmic Reticulum ◽

Cyclopiazonic Acid ◽

Significant Loss ◽

Outer Hair Cells ◽

Calcium Atpase ◽

Dependent Manner ◽

Cochlear Hair Cells ◽

Cochlear Hair Cell

An important mechanism underlying cochlear hair cell (HC) susceptibility to hypoxia/ischemia is the influx of Ca2+. Two main ATP-dependent mechanisms contribute to maintaining low Ca2+ levels: uptake of Ca2+ into intracellular stores via smooth endoplasmic reticulum calcium ATPase (SERCA) and extrusion of Ca2+ via plasma membrane calcium ATPase (PMCA). The effects of the SERCA inhibitors thapsigargin (10 nM-10 µM) and cyclopiazonic acid (CPA; 10-50 µM) and of the PMCA blockers eosin (1.5-10 µM) and o-vanadate (1-5 mM) on inner and outer hair cells (IHCs/OHCs) were examined in normoxia and ischemia using an in vitro model of the newborn rat cochlea. Exposure of the cultures to ischemia resulted in a significant loss of HCs. Thapsigargin and CPA had no effect. Eosin decreased the numbers of IHCs and OHCs by up to 25 % in normoxia and significantly aggravated the ischemia-induced damage to IHCs at 5 and 10 µM and to OHCs at 10 µM. o-Vanadate had no effect on IHC and OHC counts in normoxia, but aggravated the ischemiainduced HC loss in a dose-dependent manner. The effects of eosin and o-vanadate indicate that PMCA has an important role to play in protecting the HCs from ischemic cell death.

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Human iPSC-Derived 2D and 3D Platforms for Rapidly Assessing Developmental, Functional, and Terminal Toxicities in Neural Cells

International Journal of Molecular Sciences ◽

10.3390/ijms22041908 ◽

2021 ◽

Vol 22 (4) ◽

pp. 1908

Author(s):

Ileana Slavin ◽

Steven Dea ◽

Priyanka Arunkumar ◽

Neha Sodhi ◽

Sandro Montefusco ◽

...

Keyword(s):

High Throughput ◽

Early Stage ◽

Three Dimensional ◽

Induced Pluripotent Stem Cell ◽

Calcium Flux ◽

Neural Cells ◽

In Vitro Test ◽

Cellular Context ◽

Induced Pluripotent

With increasing global health threats has come an urgent need to rapidly develop and deploy safe and effective therapies. A common practice to fast track clinical adoption of compounds for new indications is to repurpose already approved therapeutics; however, many compounds considered safe to a specific application or population may elicit undesirable side effects when the dosage, usage directives, and/or clinical context are changed. For example, progenitor and developing cells may have different susceptibilities than mature dormant cells, which may yet be different than mature active cells. Thus, in vitro test systems should reflect the cellular context of the native cell: developing, nascent, or functionally active. To that end, we have developed high-throughput, two- and three-dimensional human induced pluripotent stem cell (hiPSC)-derived neural screening platforms that reflect different neurodevelopmental stages. As a proof of concept, we implemented this in vitro human system to swiftly identify the potential neurotoxicity profiles of 29 therapeutic compounds that could be repurposed as anti-virals. Interestingly, many compounds displayed high toxicity on early-stage neural tissues but not on later stages. Compounds with the safest overall viability profiles were further evaluated for functional assessment in a high-throughput calcium flux assay. Of the 29 drugs tested, only four did not modulate or have other potentially toxic effects on the developing or mature neurospheroids across all the tested dosages. These results highlight the importance of employing human neural cultures at different stages of development to fully understand the neurotoxicity profile of potential therapeutics across normal ontogeny.

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Pengaruh sisplatin dosis tinggi terhadap penurunan fungsi sel rambut luar koklea

Oto Rhino Laryngologica Indonesiana ◽

10.32637/orli.v40i2.1 ◽

2013 ◽

Vol 40 (2) ◽

Author(s):

Asti Kristianti ◽

Teti Madiadipoera ◽

Bogi Soeseno

Keyword(s):

Hair Cells ◽

Malignant Neoplasm ◽

Otoacoustic Emission ◽

Outer Hair Cells ◽

High Dose ◽

Distortion Product Otoacoustic Emission ◽

Inclusion Criteria ◽

Cochlear Hair Cells ◽

Distortion Product ◽

Bilateral Sensorineural Hearing Loss

Background: Chemotherapy is worldwide used nowadays, and its toxicity still remain a problemespecially toxicity to the ear (ototoxicity). Cisplatin (cis-diamminedichloroplatinum) is one of themost commonly used chemotherapy and highly potent in treating epithelial malignancies. Ototoxicitycaused by cisplatin is irreversible, progressive, bilateral, sensorineural hearing loss especially on highfrequency (4-8 KHz) accompanied by tinnitus. Purpose: To observe the cochlear outer hair cells damagein malignancies patients treated with cisplatin. Methods: This study is an observational analytic studywith prospective design to determine the influence of high dose cisplatin on cochlear outer hair cellsfunction. The research was carried out at the ENT-HNS Department, Hasan Sadikin General HospitalBandung, from November 2007 until June 2008. Audiometry, tympanometry, and distortion productotoacoustic emission (DPOAE) examinations were conducted before chemotherapy and DPOAE, andtimpanometry was again measured three days after first and second cycles of cisplatin administration. McNemar test was performed to calculate the effects of high-dose cisplatin to the cochlear outer haircells function. To compare pre and post-cisplatin on alteration of cochlear hair cells function, Wilcoxontest was used. Results: In this study 60 ears from 30 subjects that meet the inclusion criteria, consistedof 25 man (83.3%) and 5 women (16.7%). The prevalence of damaged cochlear outer hair cells were63% at first cycle and 70% at second cycle of cisplatin administration. The decline of cochlear outerhair cells function was significant (p<0.001). Conclusion: High-dose cisplatin decreases cochlear outerhair cells function in patients with malignant neoplasm. Abstrak : Latar belakang: Kemoterapi sekarang rutin digunakan secara klinis di seluruh dunia. Sejalan denganhal tersebut toksisitas kemoterapi, khususnya terhadap telinga saat ini menjadi perhatian. Sisplatin(cis-diamminedichloroplatinum) adalah salah satu obat kemoterapi yang paling banyak digunakandan paling manjur untuk terapi keganasan epitelial. Efek ototoksik sisplatin yaitu terjadi gangguandengar sensorineural yang irreversible, progresif, bilateral pada frekuensi tinggi (4-8 kHz), dan disertaidengan tinitus. Tujuan: Untuk menilai penurunan fungsi sel rambut luar koklea pada penderita tumorganas sesudah pemberian sisplatin dosis tinggi dengan menggunakan DPOAE. Metode: Studi analitikobservasional dengan rancangan prospektif di Bagian IK. THT-KL RS. Hasan Sadikin Bandung mulaibulan November 2007 sampai dengan Juni 2008. Pada penelitian ini dilakukan pemeriksaan audiometrinada murni, timpanometri, dan distortion product otoacoustic emission (DPOAE) prakemoterapi, kemudianDPOAE dan timpanometri diulang tiga hari sesudah siklus pertama dan kedua kemoterapi sisplatin. Datayang diperoleh diuji dengan uji McNemar dan uji Wilcoxon. Hasil: Dari penelitian didapat 60 telingadari 30 subjek penelitian yang memenuhi kriteria inklusi yang terdiri dari 25 laki-laki (83,3%) dan 5perempuan (16,7%). Insidens penurunan fungsi sel rambut luar koklea sebesar 63% (38 kasus) sesudahsiklus pertama dan 70% (42 kasus) sesudah siklus kedua. Hubungan penurunan fungsi sel rambut luarkoklea memberikan nilai yang sangat bermakna sejak pemberian siklus pertama (p<0,001). Kesimpulan:Pemberian sisplatin dosis tinggi pada penderita tumor ganas menyebabkan penurunan fungsi sel rambutluar koklea.Kata kunci: kemoterapi, sisplatin dosis tinggi, sel rambut luar koklea.

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Use of 3D culture systems to generate human induced pluripotent stem cell-derived [beta]-cells in vitro

Endocrine Abstracts ◽

10.1530/endoabs.57.003 ◽

2018 ◽

Author(s):

Fantuzzi Federica ◽

Toivonen Sanna ◽

Schiavo Andrea Alex ◽

Pachera Nathalie ◽

Rajaei Bahareh ◽

...

Keyword(s):

Stem Cell ◽

Beta Cells ◽

Pluripotent Stem Cell ◽

3D Culture ◽

Induced Pluripotent Stem Cell ◽

Culture Systems ◽

Induced Pluripotent

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Bestrophinopathies: perspectives on clinical disease, Bestrophin-1 function and developing therapies

Therapeutic Advances in Ophthalmology ◽

10.1177/2515841421997191 ◽

2021 ◽

Vol 13 ◽

pp. 251584142199719

Author(s):

Simranjeet Singh Grewal ◽

Joseph J. Smith ◽

Amanda-Jayne F. Carr

Keyword(s):

Pigment Epithelium ◽

Retinal Pigment ◽

Induced Pluripotent Stem Cell ◽

Underlying Disease ◽

Incomplete Penetrance ◽

Inherited Retinal Dystrophies ◽

Retinal Dystrophies ◽

High Acuity ◽

Induced Pluripotent

Bestrophinopathies are a group of clinically distinct inherited retinal dystrophies that typically affect the macular region, an area synonymous with central high acuity vision. This spectrum of disorders is caused by mutations in bestrophin1 ( BEST1), a protein thought to act as a Ca2+-activated Cl- channel in the retinal pigment epithelium (RPE) of the eye. Although bestrophinopathies are rare, over 250 individual pathological mutations have been identified in the BEST1 gene, with many reported to have various clinical expressivity and incomplete penetrance. With no current clinical treatments available for patients with bestrophinopathies, understanding the role of BEST1 in cells and the pathological pathways underlying disease has become a priority. Induced pluripotent stem cell (iPSC) technology is helping to uncover disease mechanisms and develop treatments for RPE diseases, like bestrophinopathies. Here, we provide a comprehensive review of the pathophysiology of bestrophinopathies and highlight how patient-derived iPSC-RPE are being used to test new genomic therapies in vitro.

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