The purpose of this study was to identify a membrane-bound complement inhibitor that could be overexpressed on retinal pigment epithelial cells (RPE) providing a potential therapy for age-related macular degeneration (AMD). This type of therapy may allow replacement of damaged RPE with cells that are able to limit complement activation in the retina. Complement Receptor 1 (CR1) is a membrane-bound complement inhibitor commonly found on erythrocytes and immune cells. In this study, QPCR and flow cytometry data demonstrated that CR1 is not well-expressed by RPE, indicating that its overexpression may provide extra protection from complement activation. To screen CR1 for this ability, a stable CR1-expressing ARPE19 line was created using a combination of antibiotic selection and FACS. Cell-based assays were used to demonstrate that addition of CR1 inhibited deposition of complement proteins C3b and C6 on the transfected line. In the end, this study identifies CR1 as a complement inhibitor that may be overexpressed on stem cell-derived RPE to create a potential "enhanced" cell therapy for AMD. A combination cell/complement therapy may create transplantable RPE better suited to avoid complement-mediated lysis and limit chronic inflammation in the retina.

中文翻译：

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表达补体受体1（CR1 / CD35）的视网膜色素上皮细胞，作为与年龄相关的黄斑变性的潜在疗法。

这项研究的目的是确定一种可以在视网膜色素上皮细胞（RPE）上过度表达的膜结合补体抑制剂，为年龄相关性黄斑变性（AMD）提供潜在的治疗方法。这种类型的疗法可能允许用能够限制视网膜中补体激活的细胞替代受损的RPE。补体受体1（CR1）是一种膜结合的补体抑制剂，通常存在于红细胞和免疫细胞上。在这项研究中，QPCR和流式细胞仪数据表明RPE不能很好地表达CR1，这表明CR1的过表达可能提供补体激活的额外保护。为了筛选CR1的这种能力，使用抗生素选择和FACS的组合创建了一条稳定的，表达CR1的ARPE19品系。基于细胞的分析用于证明添加CR1会抑制补体蛋白C3b和C6在转染品系上的沉积。最后，这项研究确定CR1是一种补体抑制剂，它可能在源自干细胞的RPE中过表达，从而为AMD创造了一种潜在的“增强”细胞疗法。细胞/补体疗法的组合可产生可移植的RPE，更适合于避免补体介导的裂解并限制视网膜的慢性炎症。