Sekulic Andjela, Herr Sarah M, Mulfaul Kelly, Pompös Inga-Marie, Winkler Silvia, Dietrich Carola, Obermayer Benedikt, Mullins Robert F, Conrad Thomas, Zipfel Peter F, Sennlaub Florian, Skerka Christine, Strauß Olaf
Experimental Ophthalmology, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 10117, Berlin, Germany.
Institute of Cell Biochemistry, Hannover Medical School, 30625, Hannover, Germany.
J Neuroinflammation. 2025 Jul 3;22(1):173. doi: 10.1186/s12974-025-03499-z.
Age-related macular degeneration (AMD), a multifactorial type of retinal degeneration represents the most common cause for blindness in elderly. Polymorphisms in complement factor-H increase, while absence of factor-H-related protein-1 (FHR1) decreases the AMD risk, currently explained by their opposing relationship. Here we identify a FHR1-driven pathway fostering chronic cellular inflammation. FHR1 accumulates below the retinal pigment epithelium (RPE) in AMD donor tissue and similarly the murine homolog, muFHR1 is abundant in three AMD-relevant mouse models. These mouse models express the muFHR1 receptor EGF-like module-containing mucin-like hormone receptor 1 (Emr1) on the RPE and on invading mononuclear phagocytes (MP), where both cells form clusters via muFHR1/Emr1. FHR1 ignited EMR2-dependent Ca-signals and gene expression in both human RPE cell line and in vivo where muFHR1 affects Emr1 cells (RPE and MP) gene expression shown by RNAseq analysis. As muFHR1 deletion in mice revealed significantly reduced MP invasion and neoangiogenesis in laser-induced choroidal neovascularization, we hypothesize that FHR1 accumulates, stabilizes and activates MP in the stage of RPE degeneration.
年龄相关性黄斑变性(AMD)是一种多因素导致的视网膜变性,是老年人失明的最常见原因。补体因子-H的多态性增加,而因子-H相关蛋白-1(FHR1)的缺失会降低AMD风险,目前认为这是由于它们的相反关系所致。在此,我们发现了一条由FHR1驱动的促进慢性细胞炎症的途径。FHR1在AMD供体组织的视网膜色素上皮(RPE)下方积聚,同样,小鼠同源物muFHR1在三种与AMD相关的小鼠模型中也大量存在。这些小鼠模型在RPE和侵入的单核吞噬细胞(MP)上表达muFHR1受体含EGF样模块的粘蛋白样激素受体1(Emr1),这两种细胞通过muFHR1/Emr1形成簇。FHR1在人RPE细胞系和体内均引发了依赖EMR2的钙信号和基因表达,RNAseq分析显示muFHR1在体内影响Emr1细胞(RPE和MP)的基因表达。由于小鼠中muFHR1的缺失显示激光诱导的脉络膜新生血管形成中MP浸润和新生血管形成显著减少,我们推测FHR1在RPE变性阶段积聚、稳定并激活MP。