AAV-ie-K558R mediated cochlear gene therapy and hair cell regeneration

Abstract

The cochlea consists of multiple types of cells, including hair cells, supporting cells and spiral ganglion neurons, and is responsible for converting mechanical forces into electric signals that enable hearing. Genetic and environmental factors can result in dysfunctions of cochlear and auditory systems. In recent years, gene therapy has emerged as a promising treatment in animal deafness models. One major challenge of the gene therapy for deafness is to effectively deliver genes to specific cells of cochleae. Here, we screened and identified an AAV-ie mutant, AAV-ie-K558R, that transduces hair cells and supporting cells in the cochleae of neonatal mice with high efficiency. AAV-ie-K558R is a safe vector with no obvious deficits in the hearing system. We found that AAV-ie-K558R can partially restore the hearing loss in Prestin KO mice and, importantly, deliver Atoh1 into cochlear supporting cells to generate hair cell-like cells. Our results demonstrate the clinical potential of AAV-ie-K558R for treating the hearing loss caused by hair cell death.

Increased diagnostic yield in a cohort of hearing loss families using a comprehensive stepwise strategy of molecular testing

“…One major challenge of gene therapy is effectively delivering genes to target cells, and at present, the delivery vectors contain two types: viral and non-viral. Among viral vectors, the Adeno-associated virus (AAV) vector is suitable for the treatment of hearing loss with a number of AAV serotypes have been developed, such as AAV1( Akil et al, 2012 ), AAV-ie ( Tan et al, 2019 ; Tao et al, 2022 ), AAV9-PHP.B ( Taiber et al, 2021 ), etc. In addition to gene therapy, using stem cells to induce differentiation to regenerate or repair damaged cells in the inner ear is regarded as the most feasible treatment ( He et al, 2021 ).…”

Fantastic AAV Gene Therapy Vectors and How to Find Them—Random Diversification, Rational Design and Machine Learning

“…Recently, the PHP.eB peptide [ 81 ] was rationally inserted into the shuffled AAV-DJ capsid [ 45 ] by Tan et al in order to generate a cell-penetrating phenotype for the transduction of murine cochlear supporting cells [ 41 ]. From the ensuing AAV-ie capsid, a single-amino acid mutant (AAV-ie-K558R) has most recently been derived that exhibits robust transduction of outer hair cells in neonatal mice as well [ 91 ]. This vector enabled successful treatment of hearing loss in a mouse model and demonstrated that multiple iterations of engineering can be successfully combined within a single vector lineage through additive rational modifications.…”

“…This chimera of AAV serotypes 2, 8 and 9 is capable of transducing a broad range of cell types with high efficiency in vitro, exhibits strong murine hepatic transduction in vivo, and presents an excellent scaffold for peptide display, as exemplified by the successful selection of derivatives for intranasal delivery. As mentioned above, AAV-DJ has also been employed as a scaffold to create capsids for transduction of cells in the murine inner ear [ 41 , 91 ].…”

Kölliker’s organ-supporting cells and cochlear auditory development

“…In the future, there is still a need to optimize the conditions of mouse inner ear stem cell isolated culture and proliferation, to establish a safe and efficient technology system for differentiation of inner ear stem cells into mature hair cells (Wei et al, 2021 ; Guo et al, 2022 ; Hu et al, 2022 ; Tao et al, 2022 ), to screen mouse stem cell lines that can be used for stem cell therapy (Liu et al, 2018 ; Tang et al, 2019 ); discovering new molecular markers specific for inner ear hair cells and their precursor cells (Qi et al, 2019 ), thus providing conditions for the establishment of rapid and non-destructive cell identification and sorting techniques, and thus laying a solid theoretical foundation and providing technical support for stem cell therapy for sensorineural deafness technical support.…”