PDF(Pubmed)
Abstract：
Otoferlin (OTOF) gene mutations represent the primary cause of hearing impairment and deafness in auditory neuropathy. The c.2485C>T (p. Q829X) mutation variant is responsible for approximately 3% of recessive prelingual deafness cases within the Spanish population. Previous studies have used two recombinant AAV vectors to overexpress OTOF, albeit with limited efficacy. In this study, we introduce an enhanced mini-dCas13X RNA base editor (emxABE) delivered via an AAV9 variant, achieving nearly 100% transfection efficiency in inner hair cells. This approach is aimed at treating OTOFQ829X, resulting in an approximately 80% adenosine-to-inosine conversion efficiency in humanized OtofQ829X/Q829X mice. Following a single scala media injection of emxABE targeting OTOFQ829X (emxABE-T) administered during the postnatal day 0-3 period in OtofQ829X/Q829X mice, we observed OTOF expression restoration in nearly 100% of inner hair cells. Moreover, auditory function was significantly improved, reaching similar levels as in wild-type mice. This enhancement persisted for at least 7 months. We also investigated P5-P7 and P30 OtofQ829X/Q829X mice, achieving auditory function restoration through round window injection of emxABE-T. These findings not only highlight an effective therapeutic strategy for potentially addressing OTOFQ829X-induced hearing loss but also underscore emxABE as a versatile toolkit for treating other monogenic diseases characterized by premature termination codons.
摘要：
OTOF（otoflin）基因突变是听觉神经病中听力障碍和耳聋的主要原因。c.2485C>T（p。Q829X）突变变体约占西班牙人群隐性舌前耳聋病例的3％。以前的研究已经利用两种重组AAV载体来过表达otoferlin，尽管疗效有限。在这项研究中,我们引入了通过AAV9变体提供的增强型迷你dCas13XRNA碱基编辑器（emxABE），在毛细胞中实现近100%的转染效率。这种方法旨在治疗OTOFQ829X，在人源化OtofQ829X/Q829X小鼠中产生约80%的A至I转化效率。在OtofQ829X/Q829X小鼠出生后第0-3天期间单次注射针对OTOFQ829X的emxABE（emxABE-T）后，我们观察到近100％的内毛细胞中的otoferlin表达恢复。此外，听觉功能明显改善,达到与野生型小鼠相似的水平。这种增强持续至少7个月。我们还研究了P5-7和P30OtofQ829X/Q829X小鼠，通过圆窗注射emxABE-T实现听觉功能恢复。这些发现不仅突出了可能解决OTOFQ829X引起的听力损失的有效治疗策略，而且强调了emxABE作为治疗其他以过早终止密码子为特征的单基因疾病的多功能工具包。
