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

Hui Wang; MengZhao Xun; Honghai Tang; Jingjing Zhao; Shaowei Hu; Longlong Zhang; Jun Lv; Daqi Wang; Yuxin Chen; Jianping Liu; Geng-Lin Li; Wuqing Wang; Yilai Shu; Huawei Li

doi:10.1016/j.omtn.2024.102135

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

Mol Ther Nucleic Acids. 2024 Feb 2;35(1):102135. doi: 10.1016/j.omtn.2024.102135. eCollection 2024 Mar 12.

Authors

Hui Wang^{1

2

3}, MengZhao Xun^{1

2

3}, Honghai Tang^{1

2

3}, Jingjing Zhao^{1

2

3}, Shaowei Hu^{1

2

3}, Longlong Zhang^{1

2

3}, Jun Lv^{1

2

3}, Daqi Wang^{1

2

3}, Yuxin Chen^{1

2

3}, Jianping Liu^{1

2

3}, Geng-Lin Li^{1

2

3}, Wuqing Wang^{1

2

3}, Yilai Shu^{1

2

3}, Huawei Li^{1

2

3}

Affiliations

¹ ENT Institute and Otorhinolaryngology Department of Eye & ENT Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Fudan University, Shanghai 200031, China.
² Institutes of Biomedical Science, Fudan University, Shanghai 200032, China.
³ NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai 200031, China.

Abstract

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.eB under the inner ear sensory cell-specific Myo15 promoter. Compared with the ubiquitous CAG promoter, the Myo15 promoter initiates efficient expression of the GFP fluorescence reporter in hair cells, while minimizing non-specific expression in other cell types of the inner ear and CNS. Furthermore, using the Myo15 promoter, we constructed an AAV-mediated therapeutic system with the coding sequence of OTOF gene. After inner ear injection, we observed apparent hearing recovery in Otof^-/- mice, highly efficient expression of exogenous otoferlin, and significant improvement in the exocytosis function of inner hair cells. Overall, our results indicate that gene therapy mediated by the hair cell-specific Myo15 promoter has potential clinical application for the treatment of autosomal recessive deafness and yet for other hereditary hearing loss related to dysfunction of hair cells.

Keywords: DFNB9; MT: Delivery Strategies; Myo15; gene therapy; hearing loss; specific promoter.