Loss of hair cells from vestibular epithelium results in balance dysfunction. The current therapeutic regimen for vestibular diseases is limited. Upon injury or Atoh1 overexpression, hair cell replacement occurs rapidly in the mammalian utricle, suggesting a promising approach to induce vestibular hair cell regeneration. In this study, we applied simultaneous gentamicin-mediated hair cell ablation and Atoh1 overexpression to induce neonatal utricular hair cell formation in vitro. We confirmed that type I hair cells were the primary targets of gentamicin. Furthermore, injury and Atoh1 overexpression promoted hair cell regeneration in a timely and efficient manner through robust viral transfection. Hair cells regenerated with type II characteristics in the striola and type I/II characteristics in non-sensory regions. Rare EdU⁺/myosin7a⁺ cells in sensory regions and robust EdU⁺/myosin7a⁺ signals in ectopic regions indicate that transdifferentiation of supporting cells in situ, and mitosis and differentiation of non-sensory epithelial cells in ectopic regions, are sources of regenerative hair cells. Distinct regeneration patterns in in situ and ectopic regions suggested robust plasticity of vestibular non-sensory epithelium, generating more developed hair cell subtypes and thus providing a promising stem cell-like source of hair cells. These findings suggest that simultaneously causing injury and overexpressing Atoh1 promotes hair cell regeneration efficacy and maturity, thus expanding the understanding of ectopic plasticity in neonatal vestibular organs.

前庭上皮失去毛细胞会导致平衡功能障碍。当前用于前庭疾病的治疗方案是有限的。受伤或Atoh1过表达后，毛囊细胞的置换在哺乳动物的尿囊中迅速发生，这表明诱导前庭毛细胞再生的方法很有希望。在这项研究中，我们应用庆大霉素介导的同时消融毛发和Atoh1过表达在体外诱导新生婴儿毛细胞的形成。我们证实I型毛细胞是庆大霉素的主要靶标。此外，损伤和Atoh1过表达通过健壮的病毒转染以及时有效的方式促进了毛细胞的再生。毛细胞在纹状体中具有II型特征，在非感觉区域具有I / II型特征。感觉区域中的稀有EdU ⁺ / myosin7a ⁺细胞和异位区域中的鲁棒EdU ⁺ / myosin7a ⁺信号表明，原位支持细胞的转分化以及异位区域非感觉上皮细胞的有丝分裂和分化是再生毛细胞的来源。原位不同的再生方式异位区域和前庭区域提示前庭非感觉上皮具有较强的可塑性，可产生更多发达的毛细胞亚型，从而提供了一种有希望的干细胞样毛细胞来源。这些发现表明，同时造成伤害和过度表达Atoh1可以促进毛细胞再生功效和成熟度，从而扩大了对新生儿前庭器官中异位可塑性的理解。