McDonald Andrew, Gallego Carmen, Andriessen Charlotte, Orlová Michaela, Gonçalves Manuel A F V, Wijnholds Jan
Department of Ophthalmology, Leiden University Medical Center (LUMC), Albinusdreef 2, 2333 ZA Leiden, The Netherlands.
Department of Cell and Chemical Biology, Leiden University Medical Center (LUMC), Einthovenweg 20, 2333 ZC Leiden, The Netherlands.
Int J Mol Sci. 2024 Dec 24;26(1):55. doi: 10.3390/ijms26010055.
Viral vector delivery of gene therapy represents a promising approach for the treatment of numerous retinal diseases. Adeno-associated viral vectors (AAV) constitute the primary gene delivery platform; however, their limited cargo capacity restricts the delivery of several clinically relevant retinal genes. In this study, we explore the feasibility of employing high-capacity adenoviral vectors (HC-AdVs) as alternative delivery vehicles, which, with a capacity of up to 36 kb, can potentially accommodate all known retinal gene coding sequences. We utilized HC-AdVs based on the classical adenoviral type 5 (AdV5) and on a fiber-modified AdV5.F50 version, both engineered to deliver a 29.6 kb vector genome encoding a fluorescent reporter construct. The tropism of these HC-AdVs was evaluated in an induced pluripotent stem cell (iPSC)-derived human retinal organoid model. Both vector types demonstrated robust transduction efficiency, with sustained transgene expression observed for up to 110 days post-transduction. Moreover, we found efficient transduction of photoreceptors and Müller glial cells, without evidence of reactive gliosis or loss of photoreceptor cell nuclei. However, an increase in the thickness of the photoreceptor outer nuclear layer was observed at 110 days post-transduction, suggesting potential unfavorable effects on Müller glial or photoreceptor cells associated with HC-AdV transduction and/or long-term reporter overexpression. These findings suggest that while HC-AdVs show promise for large retinal gene delivery, further investigations are required to assess their long-term safety and efficacy.
病毒载体介导的基因治疗是治疗多种视网膜疾病的一种有前景的方法。腺相关病毒载体（AAV）是主要的基因传递平台；然而，其有限的载量限制了几种临床相关视网膜基因的传递。在本研究中，我们探讨了使用高容量腺病毒载体（HC-AdV）作为替代传递载体的可行性，这种载体的容量高达36 kb，有可能容纳所有已知的视网膜基因编码序列。我们使用了基于经典5型腺病毒（AdV5）和纤维修饰的AdV5.F50版本的HC-AdV，二者都经过改造以传递一个编码荧光报告构建体的29.6 kb载体基因组。在诱导多能干细胞（iPSC）衍生的人类视网膜类器官模型中评估了这些HC-AdV的嗜性。两种载体类型均表现出强大的转导效率，在转导后长达110天观察到持续的转基因表达。此外，我们发现光感受器和Müller神经胶质细胞有高效转导，没有反应性胶质增生或光感受器细胞核丢失的证据。然而，在转导后110天观察到光感受器外核层厚度增加，提示与HC-AdV转导和/或长期报告基因过表达相关的对Müller神经胶质细胞或光感受器细胞的潜在不利影响。这些发现表明，虽然HC-AdV在大视网膜基因传递方面显示出前景，但需要进一步研究以评估其长期安全性和有效性。
