Department of Ophthalmology, Seconda Università degli Studi di Napoli, Naples, Italy.
Invest Ophthalmol Vis Sci. 2011 Jul 29;52(8):5618-24. doi: 10.1167/iovs.10-6543.
To evaluate the suitability of gene delivery-based approaches as potential treatment of Leber congenital amaurosis 4 (LCA4) due to AIPL1 mutations.
Genomic DNA from patients was analyzed using a microarray chip and direct sequencing. A detailed clinical evaluation including fundus autofluorescence (FAF) and optical coherence tomography (OCT) was performed in patients with AIPL1 mutations. Aipl1 null mice and porcine eyes were subretinally injected with adeno-associated viral (AAV) vectors harboring the human AIPL1 coding sequence.
We identified 10 LCA4 patients with mutations in AIPL1. The p.W278X sequence variation was the one most frequently found. Clinical assessment revealed common features including diffuse retinal dystrophies and maculopathy. However, optical coherence tomography showed partially retained photoreceptors in extramacular regions at all ages. The fundus autofluorescence was elicitable at the posterior pole and absent in the fovea. AAV-mediated gene transfer in Aipl1 -/- mice was associated with restoration of AIPL1 and βPDE expression in photoreceptors and protection from degeneration. Administration of a clinically relevant dose of AAV2/8-AIPL1 to the preclinical large porcine retina resulted in high level of AIPL1 photoreceptor expression in the absence of toxicity.
Using advanced imaging diagnostics we showed that maculopathy is a main feature of LCA4. We identified retinal areas at the posterior pole with surviving photoreceptors present even in adult LCA4 patients, which could be the target of gene therapy. The possible use of gene therapy for LCA4 is additionally supported by the protection from photoreceptor degeneration observed in Aipl 1-/- mice and by the high levels of photoreceptor transduction in the absence of toxicity observed after AAV2/8 delivery to the large porcine retina.
评估基于基因传递的方法作为治疗 AIPL1 突变导致的 Leber 先天性黑矇 4 型（LCA4）的潜在治疗方法的适宜性。
使用微阵列芯片和直接测序分析患者的基因组 DNA。对 AIPL1 突变患者进行详细的临床评估，包括眼底自发荧光（FAF）和光学相干断层扫描（OCT）。将携带人 AIPL1 编码序列的腺相关病毒（AAV）载体通过视网膜下腔注射到 Aipl1 基因敲除小鼠和猪眼。
我们鉴定了 10 名患有 AIPL1 突变的 LCA4 患者。最常发现的是 p.W278X 序列变异。临床评估显示包括弥漫性视网膜营养不良和黄斑病变在内的常见特征。然而，光学相干断层扫描显示在所有年龄段的黄斑区以外的区域均有部分保留的光感受器。眼底自发荧光在后极可引出，在黄斑区缺失。在 Aipl1 -/- 小鼠中进行的 AAV 介导的基因转移与光感受器中 AIPL1 和βPDE 表达的恢复以及对变性的保护有关。在临床相关剂量的 AAV2/8-AIPL1 给药于临床前大型猪视网膜后，观察到高水平的 AIPL1 光感受器表达，而无毒性。
通过先进的成像诊断，我们发现黄斑病变是 LCA4 的主要特征。我们鉴定了在成人 LCA4 患者中即使在后极也存在存活光感受器的视网膜区域，这可能是基因治疗的靶点。Aipl1 -/- 小鼠中观察到的光感受器变性保护以及在大型猪视网膜中观察到的 AAV2/8 给药后无毒性的高光感受器转导水平，进一步支持了 LCA4 基因治疗的可能性。
