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

Frontiers in Molecular Neuroscience

Tobias Moser²  Iman Bahader³  Nicola Strenzke³  Christian Vogl⁴  Anupriya Thirumalai⁵  Thomas Weber⁵  Carlos J. Duque-Afonso⁶  Nele M. Dörje⁷  Kathrin Kusch⁸  Vladan Rankovic⁸ 

[1] Auditory Neuroscience Group, Max Planck Institute of Experimental Medicine, Göttingen, Germany;Auditory Neuroscience and Optogenetics Laboratory, German Primate Center, Göttingen, Germany;Auditory Systems Physiology Group, Institute for Auditory Neuroscience and Department of Otolaryngology, University Medical Center Göttingen, Göttingen, Germany;Collaborative Research Center 889, University of Göttingen, Göttingen, Germany;Institute for Auditory Neuroscience and InnerEarLab, University Medical Center Göttingen, Göttingen, Germany;Multiscale Bioimaging Cluster of Excellence (MBExC), University of Göttingen, Göttingen, Germany;Presynaptogenesis and Intracellular Transport in Hair Cells Group, Institute for Auditory Neuroscience and InnerEarLab, University Medical Center Göttingen, Göttingen, Germany;Restorative Cochlear Genomics Group, Auditory Neuroscience and Optogenetics Laboratory, German Primate Center, Göttingen, Germany;Synaptic Nanophysiology Group, Max Planck Institute of Biophysical Chemistry, Göttingen, Germany;

关键词: gene therapy and therapeutic delivery;    deafness/hearing loss;    AAV (adeno-associated virus);    Auditory Neuroscience;    otoferlin;    preclinical;   

DOI  :  10.3389/fnmol.2020.600051

来源: DOAJ

【 摘 要 】

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

【 授权许可】

Unknown