Genetic analysis of patients with low-frequency non-syndromic hearing loss.

Low-frequency non-syndromic hearing loss (LFNSHL) is a rare auditory disorder affecting frequencies ≤ 2000 Hz. To elucidate its genetic basis, we conducted whole-exome sequencing on nine Chinese families (31 affected individuals) with LFNSHL. Four heterozygous pathogenic variants, including two novel variants, were identified in common LFNSHL-related genes (WFS1, DIAPH1) and less common genes (TNC, EYA4), achieving a 44% genetic diagnosis rate.

Programmable NIR Responsive Nanocomposite Enables Noninvasive Intratympanic Delivery of Dexamethasone to Reverse Cisplatin Induced Hearing Loss.

Local intratympanic drug delivery to the inner ear possesses significant otological clinical promise as cisplatin-induced hearing loss (CIHL) therapy, inducing significantly less side effects than systemic drug delivery. However, the multiple detoured barriers, round window membrane (RWM) and poorly controlled drug release hinder successful non-invasive drug delivery through intratympanic administration (IT). Here, a novel near-infrared (NIR) responsive nanocomposite functionalized with saponin, denoted gold nanorod@dexamethasone-mesoporous silica-saponin (AuNR@DEX-MS-saponin, NPs/DEX), is developed to enhance RWM permeation and to control the drug release spatiotemporally.

Targeted genome editing restores auditory function in adult mice with progressive hearing loss caused by a human microRNA mutation.

Mutations in () cause autosomal dominant deafness-50 (DFNA50), a form of delayed-onset hearing loss. Genome editing has shown efficacy in hearing recovery through intervention in neonatal mice, yet editing in the adult inner ear is necessary for clinical applications, which has not been done. Here, we developed a genome editing therapy for the mutation 14C>A by screening different CRISPR systems and optimizing Cas9 expression and the sgRNA scaffold for efficient and specific mutation editing.

Bilateral gene therapy in children with autosomal recessive deafness 9: single-arm trial results.

Gene therapy is a promising approach for hereditary deafness. We recently showed that unilateral AAV1-hOTOF gene therapy with dual adeno-associated virus (AAV) serotype 1 carrying human OTOF transgene is safe and associated with functional improvements in patients with autosomal recessive deafness 9 (DFNB9). The protocol was subsequently amended and approved to allow bilateral gene therapy administration.

Unveiling a novel dominant K22T mutation in a Chinese family with hearing loss.

Hearing loss constitutes one of the most prevalent conditions within the field of otolaryngology. Recent investigations have revealed that mutations in deafness-associated genes, including point mutations and variations in DNA sequences, can cause hearing impairments. With the ethology of deafness remaining unclear for a substantial portion of the affected population, further screenings for pathogenic mutations are imperative to unveil the underlying mechanisms.

Engineering of the AAV-Compatible Hair Cell-Specific Small-Size Myo15 Promoter for Gene Therapy in the Inner Ear.

Adeno-associated virus (AAV)-mediated gene therapy is widely applied to treat numerous hereditary diseases in animal models and humans. The specific expression of AAV-delivered transgenes driven by cell type-specific promoters should further increase the safety of gene therapy. However, current methods for screening cell type-specific promoters are labor-intensive and time-consuming.

Hair cell-specific Myo15 promoter-mediated gene therapy rescues hearing in DFNB9 mouse model.

Adeno-associated viral (AAV) vectors are increasingly used as vehicles for gene delivery to treat hearing loss. However, lack of specificity of the transgene expression may lead to overexpression of the transgene in nontarget tissues. In this study, we evaluated the expression efficiency and specificity of transgene delivered by AAV-PHP.

[Study on gene therapy for DPOAE and ABR threshold changes in adult mice].

This study aims to analyze the threshold changes in distortion product otoacoustic emissions（DPOAE） and auditory brainstem response（ABR） in adult mice before and after gene therapy, evaluating its effectiveness and exploring methods for assessing hearing recovery post-treatment. At the age of 4 weeks, adult mice received an inner ear injection of a therapeutic agent containing intein-mediated recombination of the gene, delivered via dual AAV vectors through the round window membrane（RWM）. Immunofluorescence staining assessed the proportion of inner ear hair cells with restored otoferlin expression and the number of synapses.

AAV1-hOTOF gene therapy for autosomal recessive deafness 9: a single-arm trial.

Background: Autosomal recessive deafness 9, caused by mutations of the OTOF gene, is characterised by congenital or prelingual, severe-to-complete, bilateral hearing loss. However, no pharmacological treatment is currently available for congenital deafness. In this Article, we report the safety and efficacy of gene therapy with an adeno-associated virus (AAV) serotype 1 carrying a human OTOF transgene (AAV1-hOTOF) as a treatment for children with autosomal recessive deafness 9.

Mechanisms and otoprotective strategies of programmed cell death on aminoglycoside-induced ototoxicity.

Aminoglycosides are commonly used for the treatment of life-threatening bacterial infections, however, aminoglycosides may cause irreversible hearing loss with a long-term clinical therapy. The mechanism and prevention of the ototoxicity of aminoglycosides are still limited although amounts of studies explored widely. Specifically, advancements in programmed cell death (PCD) provide more new perspectives.

AAV-Mediated Gene Therapy Restores Hearing in Patients with DFNB9 Deafness.

Mutations in OTOFERLIN (OTOF) lead to the autosomal recessive deafness 9 (DFNB9). The efficacy of adeno-associated virus (AAV)-mediated OTOF gene replacement therapy is extensively validated in Otof-deficient mice. However, the clinical safety and efficacy of AAV-OTOF is not reported.

Distributional comparison of different AAV vectors after unilateral cochlear administration.

The adeno-associated virus (AAV) gene therapy has been widely applied to mouse models for deafness. But, AAVs could transduce non-targeted organs after inner ear delivery due to their low cell-type specificity. This study compares transgene expression and biodistribution of AAV1, AAV2, Anc80L65, AAV9, AAV-PHP.

Targeted genome editing restores auditory function in adult mice with progressive hearing loss caused by a human microRNA mutation.

Mutations in ( ) cause dominant delayed onset hearing loss DFNA50 without treatment. Genome editing has shown efficacy in hearing recovery by intervention in neonatal mice, yet editing in the adult inner ear is necessary for clinical applications. Here, we developed an editing therapy for a C>A point mutation in the seed region of the gene, associated with hearing loss by screening gRNAs for genome editors and optimizing Cas9 and sgRNA scaffold for efficient and specific mutation editing in vitro.

Treatment of monogenic and digenic dominant genetic hearing loss by CRISPR-Cas9 ribonucleoprotein delivery in vivo.

Mutations in Atp2b2, an outer hair cell gene, cause dominant hearing loss in humans. Using a mouse model Atp2b2, with a dominant hearing loss mutation (Oblivion), we show that liposome-mediated in vivo delivery of CRISPR-Cas9 ribonucleoprotein complexes leads to specific editing of the Obl allele. Large deletions encompassing the Obl locus and indels were identified as the result of editing.

MPZL2 variant analysis with whole exome sequencing in a cohort of Chinese hearing loss patients.

Background: Hearing loss is a genetically heterogeneous disease with more than 100 genes identified. Pathogenic variants in the MPZL2 gene cause autosomal recessive non-syndromic hearing loss. MPZL2 patients showed mild to moderate progressive hearing loss with onset age around 10 years old.

Asymmetric pendrin homodimer reveals its molecular mechanism as anion exchanger.

Pendrin (SLC26A4) is an anion exchanger expressed in the apical membranes of selected epithelia. Pendrin ablation causes Pendred syndrome, a genetic disorder associated with sensorineural hearing loss, hypothyroid goiter, and reduced blood pressure. However its molecular structure has remained unknown, limiting our understanding of the structural basis of transport.

The pathogenesis of common Gjb2 mutations associated with human hereditary deafness in mice.

Mutations in GJB2 (Gap junction protein beta 2) are the most common genetic cause of non-syndromic hereditary deafness in humans, especially the 35delG and 235delC mutations. Owing to the homozygous lethality of Gjb2 mutations in mice, there are currently no perfect mouse models carrying Gjb2 mutations derived from patients for mimicking human hereditary deafness and for unveiling the pathogenesis of the disease. Here, we successfully constructed heterozygous Gjb2 and Gjb2 mutant mice through advanced androgenic haploid embryonic stem cell (AG-haESC)-mediated semi-cloning technology, and these mice showed normal hearing at postnatal day (P) 28.