Multichannel optogenetic stimulation of the auditory pathway using microfabricated LED cochlear implants in rodents

Science Translational Medicine, Journal Year: 2020, Volume and Issue: 12(553)

Published: July 22, 2020

When hearing fails, electrical cochlear implants (eCIs) provide the brain with auditory information. One important bottleneck of CIs is poor spectral selectivity that results from wide current spread each electrode contacts. Optical (oCIs) promise to make better use tonotopic order spiral ganglion neurons (SGNs) inside cochlea by spatially confined stimulation. Here, we established multichannel oCIs based on light-emitting diode (LED) arrays and used them for optical stimulation channelrhodopsin (ChR)-expressing SGNs in rodents. Power-efficient blue LED chips were integrated onto microfabricated 15-μm-thin polyimide-based carriers comprising interconnecting lines address individual LEDs a stationary or mobile driver circuitry. We extensively characterized optoelectronic, thermal, mechanical properties demonstrated stability over weeks vitro. then implanted into ChR-expressing rats gerbils, optogenetic SGN electrophysiological behavioral experiments. Improved was directly recordings midbrain. Long-term experiments deafened nontreated control animals specificity Behavioral studies carrying wireless oCI sound processor revealed percepts. This study demonstrates restoration improved an LED-based system.

Language: Английский

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Towards the translation of electroconductive organic materials for regeneration of neural tissues

Acta Biomaterialia, Journal Year: 2021, Volume and Issue: 139, P. 22 - 42

Published: July 31, 2021

Language: Английский

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Overloaded Adeno-Associated Virus as a Novel Gene Therapeutic Tool for Otoferlin-Related Deafness

Frontiers in Molecular Neuroscience, Journal Year: 2021, Volume and Issue: 13

Published: Jan. 7, 2021

Hearing impairment is the most common sensory disorder in humans. So far, rehabilitation of profoundly deaf subjects relies on direct stimulation auditory nerve through cochlear implants. However, some forms genetic hearing impairment, organ Corti structurally intact and therapeutic replacement mutated gene could potentially restore near natural hearing. In case defects otoferlin ( OTOF ), such therapy hindered by size coding sequence (~6 kb) exceeding cargo capacity (<5 preferred viral vector, adeno-associated virus (AAV). Recently, a dual-AAV approach was used to partially knock-out Otof- KO) mice. Here, we employed vitro vivo approaches assess gene-therapeutic potential naturally-occurring newly-developed synthetic AAVs overloaded with full-length Otof sequence. Upon early postnatal injection into cochlea KO mice, drove specific expression ~30% all IHCs, as demonstrated immunofluorescence labeling polymerase chain reaction. Recordings brainstem responses behavioral assay partial restoration Together, our results suggest that DFNB9—using single AAV vector—is indeed feasible, reducing complexity transfer compared approaches.

Language: Английский

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Optogenetics for visual restoration: From proof of principle to translational challenges

Progress in Retinal and Eye Research, Journal Year: 2022, Volume and Issue: 91, P. 101089 - 101089

Published: June 10, 2022

Degenerative retinal disorders are a diverse family of diseases commonly leading to irreversible photoreceptor death, while leaving the inner retina relatively intact. Over recent years, innovative gene replacement therapies aiming halt progression certain inherited have made their way into clinics. By rendering surviving neurons light sensitive optogenetic therapy now offers feasible treatment option that can restore lost vision, even in late disease stages and widely independent underlying cause degeneration. Since proof-of-concept almost fifteen years ago, this field has rapidly evolved detailed first report on treated patient recently been published. In article, we provide review approaches for vision restoration. We discuss currently available tools relative advantages disadvantages. Possible cellular targets will be discussed address question how remodelling may affect choice target what extent it limit outcomes Finally, analyse evidence against tool mediated toxicity challenges associated with clinical translation promising therapeutic concept.

Language: Английский

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The Potential of Artificial Intelligence for Assistive Technology in Education

Learning and analytics in intelligent systems, Journal Year: 2022, Volume and Issue: unknown, P. 61 - 85

Published: Jan. 1, 2022

Language: Английский

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Neurophotonic Tools for Microscopic Measurements and Manipulation: Status Report

Neurophotonics, Journal Year: 2022, Volume and Issue: 9(S1)

Published: April 27, 2022

Neurophotonics was launched in 2014 coinciding with the launch of BRAIN Initiative focused on development technologies for advancement neuroscience. For last seven years, Neurophotonics' agenda has been well aligned this focus neurotechnologies featuring new optical methods and tools applicable to brain studies. While 2.0 is pivoting towards applications these novel quest understand brain, article we review an extensive diverse toolkit explore function that have emerged from related large-scale efforts measurement manipulation structure function. Here, neurophotonic mostly animal A companion article, scheduled appear later year, will cover diffuse imaging noninvasive human each domain, outline current state-of-the-art respective technologies, identify areas where innovation needed provide outlook future directions.

Language: Английский

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PCDH15 Dual-AAV Gene Therapy for Deafness and Blindness in Usher Syndrome Type 1F Models

Journal of Clinical Investigation, Journal Year: 2024, Volume and Issue: unknown

Published: Oct. 15, 2024

Usher syndrome type 1F (USH1F), resulting from mutations in the protocadherin-15 (PCDH15) gene, is characterized by congenital lack of hearing and balance, progressive blindness form retinitis pigmentosa. In this study, we explore an approach for USH1F gene therapy, exceeding single AAV packaging limit employing a dual adeno-associated virus (AAV) strategy to deliver full-length PCDH15 coding sequence. We demonstrate efficacy mouse models, effectively restoring balance these mice. Importantly, our also proves successful expressing protein clinically relevant retinal including human organoids non-human primate retina, showing efficient targeting photoreceptors proper expression calyceal processes. This research represents major step toward advancing therapy multiple challenges hearing, vision impairment.

Language: Английский

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μLED‐based optical cochlear implants for spectrally selective activation of the auditory nerve

EMBO Molecular Medicine, Journal Year: 2020, Volume and Issue: 12(8)

Published: June 29, 2020

Article29 June 2020Open Access Transparent process μLED-based optical cochlear implants for spectrally selective activation of the auditory nerve Alexander Dieter orcid.org/0000-0002-9154-4833 Institute Auditory Neuroscience and InnerEarLab, University Medical Center Göttingen, Germany Göttingen Graduate School Neurosciences Molecular Biosciences, Search more papers by this author Eric Klein orcid.org/0000-0003-2593-059X Department Microsystems Engineering (IMTEK), Freiburg, Daniel Keppeler orcid.org/0000-0002-2638-8731 Lukasz Jablonski orcid.org/0000-0002-4288-6917 Optogenetics Laboratory, German Primate Center, Tamas Harczos orcid.org/0000-0003-3888-5636 Gerhard Hoch Vladan Rankovic orcid.org/0000-0003-0285-5232 Restorative Cochlear Genomics Group, Oliver Paul orcid.org/0000-0002-2371-7448 BrainLinks-BrainTools, Cluster Excellence, Marcus Jeschke orcid.org/0000-0002-9109-8765 Cognitive Hearing in Primates Patrick Ruther Corresponding Author [email protected] orcid.org/0000-0002-7358-003X Tobias Moser orcid.org/0000-0001-7145-0533 Max Planck Experimental Medicine, Excellence "Multiscale Bioimaging: from Machines to Networks Excitable Cells" (MBExC), Goettingen, Information Dieter1,2,†,‡, Klein3,‡, Keppeler1, Jablonski1,4, Harczos1,4, Hoch1,4, Rankovic1,4,5, Paul3,6, Jeschke1,4,7, *,3,6 *,1,2,4,8,9 1Institute 2Göttingen 3Department 4Auditory 5Restorative 6BrainLinks-BrainTools, 7Cognitive 8Auditory 9Cluster †Present address: Synaptic Wiring Lab, Neurobiology Hamburg, Hamburg-Eppendorf, ‡These authors contributed equally work *Corresponding author. Tel: +49 7612 037197; E-mail: 5513 963070; EMBO Mol Med (2020)12:e12387https://doi.org/10.15252/emmm.202012387 See also: SR Kitcher & CJC Weisz (August 2020) PDFDownload PDF article text main figures. Peer ReviewDownload a summary editorial decision including letters, reviewer comments responses feedback. ToolsAdd favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinked InMendeleyWechatReddit Figures Info Abstract Electrical (eCIs) partially restore hearing enable speech comprehension than half million users, thereby re-connecting deaf patients scene surrounding them. Yet, eCIs suffer limited spectral selectivity, resulting current spread around each electrode contact causing poor recognition presence background noise. Optogenetic stimulation might overcome limitation as light can be conveniently confined space. Here, we combined virus-mediated optogenetic manipulation spiral ganglion neurons (SGNs) microsystems engineering establish acute multi-channel implant (oCI) adult Mongolian gerbils. oCIs based on 16 microscale thin-film light-emitting diodes (μLEDs) evoked tonotopic pathway with high selectivity modest power requirements These results prove feasibility nerve. Synopsis effectiveness individuals remains electric cochlea. This study explores potential optogenetics restoration through combining engineering. rodent The strength induced scales number recruited emitters. μLED-evoked neural are selective. combination gene therapy enables higher precision paper explained Problem electrically stimulating As spreads far electrode, electrical is limited, frequency resolution implants. Results optogenetically rendered gerbil sensitive μLED-based, 16-channel We demonstrated that precision. Impact suggest μLEDs improved suffering sensorineural loss. Introduction According World Health Organization (Adrian et al, 2019), 6.1% human population suffers disabling loss, an economic impact 750 billion dollars spent treatment development. Approximately 90% cases loss dysfunction cochlea and/or today, causal therapies do not exist. Hence, methods choice aids (eCI). When profound or complete, used bypass dysfunctional lost sensory hair cells stimulate SGNs. utilize intrinsic place-frequency map (known tonotopy) SGNs provide patient information acoustic stimuli (Zeng 2008). However, while open achieved most approximately 700,000 eCI there substantial unmet clinical need improvement restoration. Current electro-conductive fluids limits spatial—and thus spectral—selectivity SGN consequently sound encoding. ultimately compromises signal perception, especially noisy environments (Kral 1998; Friesen 2001; Middlebrooks 2005). While efforts being undertaken toward activation, e.g. via multipolar (Berenstein 2008) direct electrode-neural interfacing (Middlebrooks Snyder, 2007), it seems excitation bottleneck eCIs. Recently, has been suggested stimulation, which—as opposed current—can space, could activate selectivity. Thus, (oCIs) increase artificial encoding (Richter 2011; Hernandez 2014). Two approaches have proposed SGNs: (i) infrared 2011) (ii) (Hernandez remained controversial (Verma 2014; Thompson 2015; Baumhoff use light-gated ion channels (Channelrhodopsins, ChRs) consistently reported several laboratories Duarte 2018; Hart 2020). Establishing challenging, multidisciplinary task (Kleinlogel 2020; Moser, Weiss 2016; Richardson 2017). major objectives must met: First, render coding at good temporal Second, allow Temporally precise control established fast gating ChR variants (Duarte Mager 2018). Furthermore, spatially individual fibers shown elicit 2019). studies biomedical prerequisites revealed very promising results. Toward development implants, fabricated both commercially available (LEDs) gallium nitride-based, custom-developed LEDs micrometer range (Goßler Schwaerzle Xu LED-based (Schwaerzle 2018) typically carried 10–15 emitters sized 0.22 1 mm, were manufactured up 144 60 × μm (Klein Individual these achieve output mW (corresponding emittance 400 mW/mm² μLED surface), maximum temperature K (driven 10 mA, s water) 2018), efficient enough drive ChRs safe vivo application. Peak intensity extraction further increased (by 95% 83%, respectively) implementation conical concentrators spherical micro-lenses emitter surface 2019b). any yet. In study, viral transfer ChR-variant CatCh into gerbils 16-channel, oCIs. demonstrate μLED-mediated 32-channel recordings multi-neuronal clusters midbrain manner. Modest was even some μLEDs, substantially when recruiting additional Finally, four neighboring compared clinical-style proof raises hope indeed limitations quality future. Multi-channel To sensitive, intramodiolarly injected suspension adeno-associated virus (AAV-PHP.B; Deverman 2016) carrying calcium translocating channelrhodopsin CatCh, fused reporter protein eYFP, under synapsin promoter, (Wrobel Functional expression probed brainstem activity upon illumination laser-coupled fiber round window early 4 weeks after injection (Fig 1A). Opsin function (robust optically responses, oABRs) 15/35 animals (~43%; Fig EV1). SGNs, lack obvious inner cells, post-mortem immunohistochemistry subset oABR-positive 1B–D), only sparse opsin found oABR-negative animal EV2). Animals detectable oABRs subsequent electrophysiological multi-unit central nucleus inferior colliculus (ICC) using linear multi-electrode arrays (IC datasets recorded 12 out 15 animals). For housing individually addressable (peak wavelength: 462 nm; μm, 1E F) pitch either 100, 150, 250 (center-to-center distance) embedded biocompatible epoxy medical-grade silicone 1G; roughening amounted 0.76 (± 0.21 SD) driven mA 1H) 3.15 1.1 all oCI 40 (Appendix S1). Using retroauricular approach, inserted isoflurane-anesthetized cochleostomy, whereby covered maximally third basilar membrane length 1I J). Figure 1. A. Optically response AAV-CatCh-injected ms laser pulse ˜35 (mean 1,000 stimulus presentations Hz repetition rate). B–D. Catch-eYFP-expressing apical turn identified parvalbumin (B) CatCh-eYFP (C). inlay (D′) merged immunostaining (D) indicates CatCh-EYFP (dashed white line). Scale bar: 20 μm. E, F. Scanning electron micrographs (60 footprint) structured sapphire substrate showing non-emitting p-contact side (E) emitting (F), transferred onto substrate. GaN roughened KOH etching characteristic pyramidal structures (F, inset). G. Picture 100 flexible substrate, #5 #13 (from tip) active. H. Radiant flux driving current. thick line mean, error bars SD mean. Non-functional (which did emit light, 158 560 μLEDs) excluded. I. black lines) cochleostomy basal (black, solid niche highlighted dashed line, line. SA: stapedial artery. J. 3D X-ray tomography reconstruction implanted window. Cables marked blue, indicated arrowhead; green. size Download figure PowerPoint Click here expand figure. EV1. responsesFunctional verified CatCh-injected start experiment before recordings. Optical occurred pulses ~35 radiant duration rate delivered 200 Each trace represents average one animal. oABR top right also 1A. Gray animals, which no IC data obtained (due death misplacement array). EV2. (recording parameters EV1) response. Catch-eYFP-staining transduction few 50 Acoustic calibration interpret compare across positioning along axis ICC physiologically confirmed pure tones varying intensity. Frequency tuning recording sites accessed performing cranial surgeries measuring oABRs. Characteristic frequencies derived responsive slopes calculated fit depth EV3A). Median 4.34 octaves/mm 0.42 median absolute deviation, n = 11), consistent previous where between 4.08 4.58 (Harris 1997; Schnupp deafened probe stereotactically slope regular assigned since mapping performed (n 5; EV3B). EV3. Tonotopy (normally distributed jitter 0.05 octaves added unit reduce overlay points better visualization). Tonotopic linearly fitting given depths (N 11). Data different colors. Inset: Distribution 11 contributing study. B. Electrode position 5). silicon placed normal but tonotopy mapped. Inferior first evaluated peri-stimulus time histograms (i.e., active intensity, ~3.15 mW; raw trace, scatter plot, PSTH Appendix S2), occur 3.5–17.5 onset. Since transient artifact observed traces onset, quantify set 3–20 order avoid without discarding responses. During window, increasing sorted two-dimensional matrix according corresponding site From matrix, cumulative discrimination index (d-prime, d′) spike rates intensities, starting zero condition baseline; 2007; Richter d′ quantifies change i.e., equal rise firing SD. estimate patterns spatial curves (STCs) constructed iso-contour lines integer values 2A–D). A bilateral intracochlear application kanamycin, leads cell hence creates model Deafening clicks. Mean thresholds click-evoked 30 ± 0 dB SPL deafening 5), clicks 5–10 days kanamycin 2E). still possible 2F G). Neural vanished sacrificed 2H). 2. evoke A–D. Exemplar STCs single (A), block (B), CatCh-transduced (C) wild-type (WT; D). spaced E. (average Hz) click (left) (right; star: threshold). (right), elicited duration, (1,000 presented Hz), same system deafening. Differences amplitude waveform likely due electrodes fiber. G, CatCh-transduced, kanamycin-deafened (G) (H) sacrifice. Maximum (indiv.; 129/77 N 9/3 hearing/deaf gerbils), (block; 62/27 blocks (all; 24/9 gerbils) (˜35 stimulations (one-way ANOVA (F-value: 73.25, degrees freedom, P 5.19 10−45) post-hoc multiple comparison test; indiv. vs. block: 9.9 10−9; all: 0.0096; fiber: 0.0016; WT: 10−9;**P < 0.01, ***P 0.001, n.s. non-significant). WT 7/7 oCIs, 2/2 (post-mortem; 5/1 gerbils). Brown dots indicate animals. Number (d′ > 1; mean 30.18, 1.42 10−21) 6.8 10−5; 0.006; 0.25; **P Responses hearin

Language: Английский

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Bipolar cell targeted optogenetic gene therapy restores parallel retinal signaling and high-level vision in the degenerated retina

Communications Biology, Journal Year: 2022, Volume and Issue: 5(1)

Published: Oct. 20, 2022

Abstract Optogenetic gene therapies to restore vision are in clinical trials. Whilst current approaches target the ganglion cells, output neurons of retina, new molecular tools enable efficient targeting first order retinal interneurons, bipolar with potential a higher quality vision. Here we investigate signaling and behavioral blind mice treated cell targeted optogenetic therapies. All tested tools, including medium-wave opsin, Opto-mGluR6, two melanopsin based chimeras restored visual acuity contrast sensitivity. The best performing opsin was melanopsin-mGluR6 chimera, which some cases acuities sensitivities that match wild-type animals. Light responses from cells were robust diverse receptive-field types, inferring elaborate inner signaling. Our results highlight optogenetics recover high-level human patients end-stage degenerations.

Language: Английский

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Is there an unmet medical need for improved hearing restoration?

EMBO Molecular Medicine, Journal Year: 2022, Volume and Issue: 14(8)

Published: July 14, 2022

Language: Английский

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