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Principal Investigator: Carl Nist-Lund
Organization: HARVARD MEDICAL SCHOOL
Fiscal Year: 2024
Award: $36,919
Funding agency: National Institute on Deafness and Other Communication Disorders
Abstract: Novel inner ear organoid models for studying hair cells in normal development and in the deaf-
blindness disease Usher Syndrome Type 1F
The fundamental human sense of balance, which comprises both movement through the world and one’s body
position in space, begins with specialized biological detectors called “hair cells” responsible for converting
mechanical stimuli into electrical signals (also known as mechanotransduction). Hair cells perform this function
by converting mechanical stimuli on their apical surface (received by a specialized structure of actin-rich
stereocilia) into electrical impulses on their basolateral surface (produced by specialized ribbon synapses).
Despite their critical role and decades of study in animal models, many aspects of the hallmarks of hair cell
development specifically in developing human tissue have yet to be explored. To circumvent the difficulty in
access, collection, and preservation of in vivo or ex vivo human tissue, human induced pluripotent stem cell
(hiPSC) derived inner ear organoids (IEOs) have emerged as a new model for studying human development.
IEOs are 3D aggregates of cells containing many internal vesicles lined with inner ear sensory epithelia and
synapsing neurons. Strong histologic and limited transcriptomic data of IEOs show that the in vitro organoids
recapitulate many of the diverse features found in the in vivo inner ear. Unfortunately, the sensory cells of interest
are buried by a large population of supporting and mesenchymal cells, preventing their long-term developmental
and functional study. My recent work in the lab has shown that perturbation of extracellular matrix proteins
reverses the polarity of the sensory epithelia such that the progenitor epithelia remain on the surface and have
their apical surfaces pointed outwards into the media. The outwardly facing hair cells with this new method are
now both accessible and imageable, overcoming the limitations of previous IEO versions. Based on initial
characterization, I hypothesize that inverted apical-out IEOs yield more numerous and more functionally mature
hair cells. In Aim 1, I will characterize the genetic and physiologic properties of the human hair cell population
that is now accessible through our in vitro model. I will perform single cell RNA sequencing in the mature organoid
and bathe the organoids in artificial solutions that mimic in vivo endolymph to attempt to mature the transcriptomic
and electrophysiological profiles of the hair cells. In Aim 2, I will use a patient-derived hiPSC line from a patient
with a devastating genetic deaf-blindness mutation known as USH1F to investigate the development of critical
apical structures and the disrupted effects that damage hair cell function. I will then attempt to use viral-mediated
gene therapies before the onset of hair cell dysfunction to restore proper hair cell development. These
experiments will reveal the first generation of many applications of this new approach to generate apical-out
inner ear organoids in order to study human development, disease progression, and as a platform to develop
novel therapeutics.
Terms: <3-D><3-Dimensional><3D><Actins><Animal Model><Animal Models and Related Studies><Apical><Area><Basal lamina><Bathing><Baths><Benchmarking><Best Practice Analysis><Biological><Blindness><Body Tissues><Bypass><CDH23><CDH23 gene><CDHR23><Cadherin-23><Cadherin-Related Family, Member 23><Cell Aggregation><Cell Body><Cell Communication and Signaling><Cell Function><Cell Line><Cell Physiology><Cell Process><Cell Signaling><Cell-Extracellular Matrix><CellLine><Cells><Cellular Function><Cellular Mechanotransduction><Cellular Physiology><Cellular Process><Cilia><Clinical Trials><Collection><Corti Cell><DNA Therapy><Data><Deaf and blind><Deafblind><Development><Disease><Disease Progression><Disorder><Dysfunction><ECM><Electron Microscopy><Electrophysiology><Electrophysiology (science)><Endolymph><Environment><Epithelium><Equilibrium><Extracellular Matrix><Extracellular Matrix Proteins><Functional disorder><Future><Gene Transfer Clinical><Generations><Genetic><Genetic Alteration><Genetic Change><Genetic Diseases><Genetic Intervention><Genetic defect><Graefe-Usher syndrome><Hair Cells><Hallgren syndrome><Hearing Disorders><Hearing Loss><Hearing problem><Hereditary Disease><Histologic><Histologically><Human><Human Development><Hypoacuses><Hypoacusis><Image><In Vitro><Inborn Genetic Diseases><Individual><Inherited disorder><Inner Ear Disorder><Inner Hair Cells><Inner ear hair cells><Internal Ear><Intracellular Communication and Signaling><Ion Channel><Ionic Channels><Labyrinth><Mechanical Signal Transduction><Mechanics><Mechanosensory Transduction><Mediating><Membrane Channels><Mesenchymal><Methods><Mice><Mice Mammals><Modeling><Modern Man><Molecular><Morphology><Movement><Murine><Mus><Mutation><Nerve Cells><Nerve Unit><Neural Cell><Neurocyte><Neurons><Neurophysiology / Electrophysiology><Organoids><Otic Vesicle><Otocadherin><Outcome><PCDH15><PCDH15 gene><Pathogenicity><Pathology><Patients><Phenotype><Physiologic><Physiological><Physiopathology><Population><Procedures><Process><Progenitor Cells><Property><Proteins><Recovery of Function><Role><Sampling><Sensory><Sensory Disorders><Severities><Signal Transduction><Signal Transduction Systems><Signaling><Staining method><Stains><Stimulus><Strains Cell Lines><Structure><Study models><Subcellular Process><Surface><Synaptic ribbon><Techniques><Testing><Therapeutic><Therapeutic Intervention><Thin Filament><Time><Tissues><Translating><Usher Syndrome><Usher's syndrome><Utricle structure><Utricles><Vesicle><Vestibular System Impairment><Vestibular defect><Vestibular dysfunction><Vestibular problems><Viral><Virus><Work><auditory disease><auditory disorder><auditory dysfunction><auditory problem><balance><balance disorder><balance function><balance impairment><benchmark><biologic><biological signal transduction><body movement><body position><cell type><ciliopathy><cultured cell line><detector><develop therapy><developmental><disturbed balance><dysfunctional hearing><dystrophia retinae pigmentosa-dysostosis syndrome><dystrophia retinae-dysacousis syndrome><ear hair cell><early onset><electrophysiological><epithelial progenitor><epithelial progenitor cell><epithelial stem cell><equilibration disorder><equilibrium disorder><experiment><experimental research><experimental study><experiments><extracellular><fetal><functional recovery><gene repair therapy><gene replacement><gene therapy><gene-based therapy><genetic condition><genetic disorder><genetic therapy><genome mutation><genomic therapy><hearing challenged><hearing defect><hearing deficient><hearing deficit><hearing difficulty><hearing disease><hearing dysfunction><hearing impairment><hereditary disorder><heritable disorder><hiPSC><human iPS><human iPSC><human induced pluripotent cell><human induced pluripotent stem cells><human inducible stem cells><human tissue><imaging><in vitro Model><in vivo><inborn error><induced human pluripotent stem cells><induced pluripotent stem cells derived from patients><induced pluripotent stem cells from patients><inherited diseases><inherited genetic disease><inherited genetic disorder><inner ear><inner ear diseases><interest><intervention development><intervention therapy><mechanic><mechanical><mechanical stimulus><mechanosensing><mechanotransduction><model of animal><neuronal><new approaches><new drug treatments><new drugs><new pharmacological therapeutic><new therapeutics><new therapy><next generation therapeutics><novel><novel approaches><novel drug treatments><novel drugs><novel pharmaco-therapeutic><novel pharmacological therapeutic><novel strategies><novel strategy><novel therapeutics><novel therapy><patch clamp><pathophysiology><patient - derived stem cells><patient derived human iPS><patient derived human iPSC><patient derived human induced pluripotent stem cell><patient derived iPS><patient derived iPSC><patient derived induced pluripotent cells><patient derived induced pluripotent stem cells><patient derived progenitor><patient matched stem cell><patient-derived pluripotent stem cells><postnatal><preservation><presynaptic><prevent><preventing><progenitor><protein expression><protocadherin 15><protocadherin-related 15><response><retinitis pigmentosa-congenital deafness syndrome><ribbon synapse><scRNA-seq><single cell RNA-seq><single cell RNAseq><single cell expression profiling><single cell transcriptomic profiling><single-cell RNA sequencing><social role><sound><stem cell organoids><stem cell-derived organoids><stem cells><therapy development><three dimensional><transcriptomics><treatment development><vestibular deficit><vestibular impairment><vestibular system dysfunction><vision loss><visual loss>