Institute for Ophthalmic Research, Department for Ophthalmology, Eberhard Karls University of Tübingen, 72076 Tübingen, Germany.
Faculty of Medicine, University of Queensland, Herston, QLD 4006, Australia.
Biomolecules. 2021 Nov 3;11(11):1621. doi: 10.3390/biom11111621.
Age-related Macular degeneration (AMD) is a degenerative disease of the macula affecting the elderly population. Treatment options are limited, partly due to the lack of understanding of AMD pathology and the lack of suitable research models that replicate the complexity of the human macula and the intricate interplay of the genetic, aging and lifestyle risk factors contributing to AMD. One of the main genetic risks associated with AMD is located on the Complement Factor H () gene, leading to an amino acid substitution in the Factor H (FH) protein (Y402H). However, the mechanism of how this FH variant promotes the onset of AMD remains unclear. Previously, we have shown that FH deprivation in RPE cells, via silencing, leads to increased inflammation, metabolic impairment and vulnerability toward oxidative stress. In this study, we established a novel co-culture model comprising silenced RPE cells and porcine retinal explants derived from the visual streak of porcine eyes, which closely resemble the human macula. We show that retinae exposed to FH-deprived RPE cells show signs of retinal degeneration, with rod cells being the first cells to undergo degeneration. Moreover, via Raman analyses, we observed changes involving the mitochondria and lipid composition of the co-cultured retinae upon FH loss. Interestingly, the detrimental effects of FH loss in RPE cells on the neuroretina were independent of glial cell activation and external complement sources. Moreover, we show that the co-culture model is also suitable for human retinal explants, and we observed a similar trend when RPE cells deprived of FH were co-cultured with human retinal explants from a single donor eye. Our findings highlight the importance of RPE-derived FH for retinal homeostasis and provide a valuable model for AMD research.
年龄相关性黄斑变性（AMD）是一种影响老年人群的黄斑退行性疾病。治疗选择有限，部分原因是对 AMD 病理学的理解不足，以及缺乏合适的研究模型来复制人类黄斑的复杂性和导致 AMD 的遗传、衰老和生活方式风险因素的复杂相互作用。与 AMD 相关的主要遗传风险之一位于补体因子 H（）基因上，导致因子 H（FH）蛋白中的氨基酸取代（Y402H）。然而，这种 FH 变体如何促进 AMD 的发病机制仍不清楚。以前，我们已经表明，通过沉默 FH 在 RPE 细胞中的缺失会导致炎症增加、代谢损伤和对氧化应激的脆弱性。在这项研究中，我们建立了一种新的共培养模型，包括沉默的 RPE 细胞和源自猪眼视觉条纹的猪视网膜外植体，该模型非常类似于人类黄斑。我们表明，暴露于 FH 缺失的 RPE 细胞的视网膜显示出视网膜变性的迹象，其中杆细胞是首先发生变性的细胞。此外，通过拉曼分析，我们观察到在 FH 丢失时共培养的视网膜中涉及线粒体和脂质组成的变化。有趣的是，RPE 细胞中 FH 缺失对神经视网膜的有害影响独立于神经胶质细胞激活和外部补体来源。此外，我们表明该共培养模型也适用于人视网膜外植体，并且当 FH 缺失的 RPE 细胞与来自单个供体眼的人视网膜外植体共培养时，我们观察到类似的趋势。我们的研究结果强调了 RPE 衍生的 FH 对视网膜内稳态的重要性，并为 AMD 研究提供了一个有价值的模型。
