Department of Ophthalmology, Visual and Anatomical Sciences, Wayne State University School of Medicine, Detroit, MI, USA.
Gene Ther. 2024 Nov;31(11-12):572-579. doi: 10.1038/s41434-024-00485-7. Epub 2024 Sep 5.
Optogenetics is a promising approach for restoring vision to the blind after photoreceptor degeneration. The ability to restore vision through AAV-mediated delivery of light-sensitive proteins, especially channelrhodopsins, into retinal ganglion cells has been extensively demonstrated in animal models. For clinical application, knowledge of viral dose-dependent functional efficacy is desired. In this study, using a triple-knockout blind mouse model and a highly light-sensitive channelrhodopsin variant, we evaluated viral dose-dependent vision restoration through retinal ganglion cell expression by using optomotor behavioral assays. Our results show that both the restored light sensitivity and visual acuity reached peak levels at a medial viral dose of 10 vg. With increasing dose, transduction efficiency continued to increase while protein expression peaked at the dose of ~10 vg and declined at higher doses. Also, a significant increase in retinal gliosis and inflammatory responses started at the dose of ~10 vg, and a marked increase was observed at the dose of ~10. These results provide valuable insights into viral dose design for clinical studies.
光遗传学是一种有前途的方法，可以在光感受器退化后恢复盲人的视力。通过将光敏感蛋白（尤其是通道视紫红质）经 AAV 递送至视网膜神经节细胞来恢复视力，在动物模型中已经得到了广泛的证实。对于临床应用，需要了解病毒剂量依赖性的功能效果。在这项研究中，我们使用三重基因敲除盲鼠模型和一种高敏通道视紫红质变体，通过视动行为检测评估了通过视网膜神经节细胞表达的病毒剂量依赖性视力恢复。我们的结果表明，在中等病毒剂量（10vg）时，恢复的光敏感性和视力锐度均达到峰值。随着剂量的增加，转导效率继续增加，而蛋白表达在10vg 的剂量时达到峰值，并在更高的剂量下下降。此外，在10vg 的剂量时，视网膜神经胶质增生和炎症反应显著增加，在~100vg 的剂量时观察到明显增加。这些结果为临床研究中的病毒剂量设计提供了有价值的见解。
