CICS-UBI - Health Sciences Research Centre, University of Beira Interior, Covilhã, Portugal.
Functional Proteomics Laboratory, Centro Nacional de Biotecnología, CSIC, Madrid, Spain.
Front Immunol. 2023 Feb 16;14:1107295. doi: 10.3389/fimmu.2023.1107295. eCollection 2023.
Diabetic retinopathy (DR) and age-related macular degeneration (AMD) are leading causes of visual impairment and blindness in people aged 50 years or older in middle-income and industrialized countries. Anti-VEGF therapies have improved the management of neovascular AMD (nAMD) and proliferative DR (PDR), no treatment options exist for the highly prevalent dry form of AMD.
To unravel the biological processes underlying these pathologies and to find new potential biomarkers, a label-free quantitative (LFQ) method was applied to analyze the vitreous proteome in PDR (n=4), AMD (n=4) compared to idiopathic epiretinal membranes (ERM) (n=4).
Post-hoc tests revealed 96 proteins capable of differentiating among the different groups, whereas 118 proteins were found differentially regulated in PDR compared to ERM and 95 proteins in PDR compared to dry AMD. Pathway analysis indicates that mediators of complement, coagulation cascades and acute phase responses are enriched in PDR vitreous, whilst proteins highly correlated to the extracellular matrix (ECM) organization, platelet degranulation, lysosomal degradation, cell adhesion, and central nervous system development were found underexpressed. According to these results, 35 proteins were selected and monitored by MRM (multiple reaction monitoring) in a larger cohort of patients with ERM (n=21), DR/PDR (n=20), AMD (n=11), and retinal detachment (n=13). Of these, 26 proteins could differentiate between these vitreoretinal diseases. Based on Partial least squares discriminant and multivariate exploratory receiver operating characteristic (ROC) analyses, a panel of 15 discriminatory biomarkers was defined, which includes complement and coagulation components (complement C2 and prothrombin), acute-phase mediators (alpha-1-antichymotrypsin), adhesion molecules (e.g., myocilin, galectin-3-binding protein), ECM components (opticin), and neurodegeneration biomarkers (beta-amyloid, amyloid-like protein 2).
在中高收入国家和工业化国家，50 岁及以上人群中导致视力损害和失明的主要原因是糖尿病性视网膜病变（DR）和年龄相关性黄斑变性（AMD）。抗血管内皮生长因子治疗改善了新生血管性 AMD（nAMD）和增生性 DR（PDR）的治疗管理，但对于高度流行的干性 AMD 尚无治疗选择。
为了揭示这些病变的生物学过程并寻找新的潜在生物标志物，应用无标记定量（LFQ）方法分析了增生性 DR（n=4）、AMD（n=4）与特发性视网膜内膜（ERM）（n=4）的玻璃体蛋白质组。
事后检验显示，96 种蛋白可区分不同组，而与 ERM 相比，PDR 中有 118 种蛋白差异表达，与干性 AMD 相比，PDR 中有 95 种蛋白差异表达。通路分析表明，补体、凝血级联和急性期反应的介质在 PDR 玻璃体中富集，而与细胞外基质（ECM）组织、血小板脱颗粒、溶酶体降解、细胞黏附和中枢神经系统发育高度相关的蛋白表达下调。根据这些结果，选择了 35 种蛋白，并通过 MRM（多重反应监测）在更大的 ERM 患者队列（n=21）、DR/PDR（n=20）、AMD（n=11）和视网膜脱离（n=13）中进行监测。其中，26 种蛋白可区分这些玻璃体视网膜疾病。基于偏最小二乘法判别和多元探索性接收器工作特征（ROC）分析，定义了一个由 15 种有区别的生物标志物组成的面板，其中包括补体和凝血成分（补体 C2 和凝血酶原）、急性期介质（α-1-抗胰蛋白酶）、黏附分子（如肌球蛋白、半乳糖凝集素-3 结合蛋白）、细胞外基质成分（视蛋白）和神经退行性变生物标志物（β-淀粉样蛋白、淀粉样蛋白样蛋白 2）。
