Decellularized Aged Bruch's Membrane Confers Unique Biochemical Cues to Retinal Pigment Epithelium for In Vitro Modeling of Age-Related Macular Degeneration.

Age-related macular degeneration (AMD), a chronic inflammatory disease, is a major cause of irreversible blindness worldwide. It involves the degeneration of the retinal pigment epithelium (RPE) and the accumulation of deposits between the RPE and the Bruch's membrane (BrM), ultimately leading to photoreceptor death. The multifactorial and chronic nature of AMD makes it challenging to model in vitro. We developed a biomaterial based on decellularized BrM (dECM-BrM) from aged donors to evaluate its ability to induce an AMD-like phenotype in RPE monolayers. BrM from 5 young and 5 aged human donors was decellularized and the protein profile analyzed by LC-MS/MS. dECM-BrM was then used as a coating substrate for RPE culture. A total of 281 proteins were identified and proteomic analysis screened 49 differentially expressed proteins in aged dECM-BrM. Gene Ontology analysis showed that they were associated with extracellular region, antioxidant activity, lipid metabolism and transport. Moreover, the KEGG pathway related to complement and coagulation cascade was significantly enriched. RPE culture on aged dECM-BrM allowed RPE polarization and after 60 days, transepithelial electrical resistance significantly decreased compared to RPE grown on young dECM-BrM, accompanied by increased IL-33 secretion and marked expression of drusen components such as vitronectin and apolipoprotein E, lipid deposition and complement factors C3 and C9. We showed a successful approach to obtain a BrM mimic based on decellularized BrM that ensured cellular removal while preserving ECM structure and identified differentially expressed proteins in aged dECM-BrM that may provide specific biochemical cues fundamental to model AMD in vitro.