Hector Mandy, Behnke Verena, Dabrowska-Schlepp Paulina, Busch Andreas, Schaaf Andreas, Langmann Thomas, Wolf Anne
Laboratory for Experimental Immunology of the Eye, Department of Ophthalmology, University of Cologne, Faculty of Medicine and University Hospital Cologne, 50931, Cologne, Germany.
Eleva GmbH, Hans-Bunte-Straße 19, 79108, Freiburg, Germany.
J Neuroinflammation. 2025 Apr 11;22(1):104. doi: 10.1186/s12974-025-03418-2.
AMD is a multifactorial progressive disease of the central retina that leads to severe vision loss among the elderly. Genome-wide association studies in AMD patients and preclinical data have identified a dysregulated complement system and aberrant microglia responses in the pathogenesis of AMD. Specifically, a genetic variant in the complement factor H (CFH) gene, an important inhibitor of the alternative complement pathway, confers the strongest risk for AMD. Here, we investigated whether moss-derived recombinant human CFH proteins, termed CPV-101 and CPV-104, can modulate microglia reactivity and limit retinal degeneration in a murine light damage paradigm mimicking important features of AMD.
Two glycosylated human recombinant CFH proteins CPV101, and CPV-104 were produced in moss suspension cultures. In addition, glycans of the CPV-104 variant are sialylated, an optimization that makes CPV-104 an analog of human CFH. BALB/cJ mice received intravitreal injections of 5 µg CPV-101 and CPV-104 or vehicle, starting 1 day prior to exposure to 10,000 lx white light for 30 min. The effects of CPV-101 and CPV-104 treatment on mononuclear phagocyte and Müller cell reactivity were analyzed by immunostainings of retinal sections and flat mounts. Gene expression of microglia markers was analyzed using quantitative real-time PCR (qRT-PCR). Optical coherence tomography (OCT); Blue Peak Autofluorescence (BAF); terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining, and morphometric analyses were used to quantify the extent of retinal degeneration and photoreceptor apoptosis.
Light-exposed mice treated with moss-derived recombinant human full-length CFH showed reduced complement activation and MAC deposition in the retina. Concomitantly, mononuclear phagocyte and Müller cell reactivity in light-exposed retinas were also ameliorated upon CFH substitution. Moreover, attenuated light-induced retinal degeneration was detected in mice that received moss-derived CFH.
Modulating the alternative complement pathway using moss-derived recombinant human full-length CFH variant CPV-101 and CPV-104 counter-regulate gliosis and attenuates light-induced retinal degeneration, highlighting a promising concept for the treatment of AMD patients.
年龄相关性黄斑变性（AMD）是一种影响视网膜中央区域的多因素进展性疾病，可导致老年人严重视力丧失。对AMD患者进行的全基因组关联研究以及临床前数据表明，补体系统失调和小胶质细胞反应异常在AMD发病机制中起作用。具体而言，补体因子H（CFH）基因的一个遗传变异，作为替代补体途径的重要抑制剂，是AMD最强的风险因素。在此，我们研究了苔藓来源的重组人CFH蛋白CPV - 101和CPV - 104，在模拟AMD重要特征的小鼠光损伤模型中，是否能够调节小胶质细胞反应性并限制视网膜变性。
在苔藓悬浮培养物中产生了两种糖基化的人重组CFH蛋白CPV101和CPV - 104。此外，CPV - 104变体的聚糖被唾液酸化，这种优化使CPV - 104成为人CFH的类似物。BALB/cJ小鼠在暴露于10000勒克斯白光30分钟前1天开始，接受玻璃体内注射5μg CPV - 101和CPV - 104或溶剂。通过视网膜切片和铺片免疫染色分析CPV - 101和CPV - 104治疗对单核吞噬细胞和Müller细胞反应性的影响。使用定量实时PCR（qRT-PCR）分析小胶质细胞标志物的基因表达。光学相干断层扫描（OCT）、蓝峰自发荧光（BAF）、末端脱氧核苷酸转移酶dUTP缺口末端标记（TUNEL）染色和形态计量分析用于量化视网膜变性和光感受器凋亡的程度。
用苔藓来源的重组人全长CFH处理的光暴露小鼠视网膜中的补体激活和膜攻击复合物（MAC）沉积减少。同时，CFH替代后，光暴露视网膜中的单核吞噬细胞和Müller细胞反应性也得到改善。此外，在接受苔藓来源CFH的小鼠中检测到光诱导的视网膜变性减轻。
使用苔藓来源的重组人全长CFH变体CPV - 101和CPV - 104调节替代补体途径可对抗胶质增生并减轻光诱导的视网膜变性，为治疗AMD患者提供了一个有前景的概念。
