Subretinal fibrosis is associated with worse visual outcomes in patients with neovascular age-related macular degeneration. As there is a lack of optimal biomarkers and no method that directly detects collagen in the back of the eye, novel tools that monitor fibrosis-related changes in neovascular age-related macular degeneration are needed. Here, using two mouse models (the laser-induced choroidal neovascularization model, and the JR5558 mouse presenting with spontaneous subretinal neovascularization with fibrosis), we imaged active fibrotic lesions using fluorescently labeled collagen hybridizing peptides (CHPs), short peptides that bind to single α-chain collagen structures during collagen remodeling. JR5558 retinal pigment epithelium/choroid flat mounts showed CHP co-staining with fibrosis and epithelial mesenchymal transition-related markers; additionally, CHP histopathology staining correlated with in vivo CHP imaging. After laser-induced choroidal neovascularization, in vivo CHP binding correlated with laser intensity, histopathology CHP and fibronectin staining. Laser-induced choroidal neovascularization showed decreased CHP intensity over time in healing/regressing versus active scars in vivo, whereas increased CHP binding correlated with elevated fibrosis in JR5558 mouse eyes with age. In bispecific angiopoietin 2/vascular endothelial growth factor antibody-treated JR5558 mice, CHPs detected significantly decreased collagen remodeling versus immunoglobulin G control. These results demonstrate the first use of CHPs to directly image remodeling collagen in the eye and as a potential clinical optical biomarker of active subretinal fibrosis associated with ocular neovascularization.

视网膜下纤维化与新生血管性年龄相关性黄斑变性患者的视力结果较差相关。由于缺乏最佳的生物标志物，也没有直接检测眼睛后部胶原蛋白的方法，因此需要监测新生血管性年龄相关性黄斑变性中纤维化相关变化的新工具。在这里，使用两种小鼠模型（激光诱导脉络膜新生血管模型和出现自发性视网膜下新生血管伴纤维化的 JR5558 小鼠），我们使用荧光标记的胶原杂交肽 (CHP)（与单个 α 结合的短肽）对活动性纤维化病变进行成像。 -胶原蛋白重塑过程中的链状胶原蛋白结构。 JR5558 视网膜色素上皮/脉络膜平片显示 CHP 与纤维化和上皮间质转化相关标记物共染色；此外，CHP 组织病理学染色与体内 CHP 成像相关。激光诱导脉络膜新生血管形成后，体内 CHP 结合与激光强度、组织病理学 CHP 和纤连蛋白染色相关。与体内活动性疤痕相比，激光诱导的脉络膜新生血管在愈合/消退中显示出随着时间的推移，CHP 强度降低，而随着年龄的增长，CHP 结合的增加与 JR5558 小鼠眼睛纤维化的加剧相关。在双特异性血管生成素 2/血管内皮生长因子抗体处理的 JR5558 小鼠中，CHP 检测到与免疫球蛋白 G 对照相比，胶原重塑显着减少。这些结果证明了首次使用 CHP 直接对眼中的重塑胶原进行成像，并作为与眼新生血管形成相关的活动性视网膜下纤维化的潜在临床光学生物标志物。