Protective Role of Decellularized Human Amniotic Membrane from Oxidative Stress-Induced Damage on Retinal Pigment Epithelial Cells

Oxidative stress is an important cause for several retinal aging diseases. Cell therapy using a decellularized human amniotic membrane (dHAM) as a tissue scaffold for retinal pigment epithelial cells has a potential therapeutic role under such pathological conditions. This is attributed by the anti-inflammatory, antimicrobial, low-immunogenicity aspects of dHAM, apart from harboring a drug reservoir potential. The underlying mechanisms for maintaining the physiological properties of transplanted cells and their survival in a diseased milieu using dHAM has remained unexplored/unanswered. Hence, we investigated the potential role of dHAM in preserving the cellular functions of retinal pigment epithelium in an oxidative stress environment. Adult human retinal pigment epithelial (ARPE-19) cells were cultured on dHAM or tissue culture dishes under hyperoxia. Gene expression, immunofluorescence staining, enzyme-linked immunosorbent assay (ELISA), and scanning electron microscopy (SEM) were performed to assess the levels of reactive oxygen species, proliferation, apoptosis, epithelial-mesenchymal transition, phagocytosis, and secretion of vascular endothelial factors. These results indicate reduced epithelial-mesenchymal transition, generation of reactive oxygen species (p <= 0.0001), and apoptosis (p <= 0.05) in cells cultured on dHAM, compared to those on tissue culture dishes under oxidative stress conditions. Concomitantly, the secretion of the vascular endothelial growth factor was significantly reduced (p <= 0.01) on dHAM. Phagocytic activity was significantly higher (p <= 0.001) in cells cultured on dHAM and were comparable to those cells cultured on tissue culture dishes. SEM images showed a clustered growth pattern on dHAM compared to an elongated morphology when cultured on tissue culture dishes under oxidative stress conditions. These findings demonstrate the utility of dHAM as a scaffold for growing retinal epithelial cells and to maintain their physiological properties in an oxidative stress condition with a potential to develop regenerative medicine strategies to treat degenerative eye diseases.