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Aims/Purpose: Posterior ocular diseases, such as glaucoma and diabetic retinopathy (DR), are the main causes of blindness worldwide. Among the possible therapeutic approaches particular interest was turned to neurotrophic factors, such as Nerve Growth Factor (NGF), and to mesenchymal stem cells (MSCs)‐derived factors. Nevertheless, the local drugs and factors delivery in the eye remains a challenge. Therefore, using an in vitro model of glaucoma and an ex vivo model of DR, this study aimed to test the feasibility to use decellularized human corneal lenticule (hCL) as natural delivery system able to vehicle neurotrophic and MSCs‐regenerative factors. Methods: hCLs (thickness 100–120 μm) collected from donors undergoing refractive surgery, were decellularized (0.1% SDS) and engineered with MSCs from human amniotic fluid (hAFSCs) and/or with microparticles containing rhNGF (rhNGF‐MPs). Human Trabecular Meshwork cells (HTMCs), damaged with Transforming Growth Factor‐β2 (TGF‐β2; 5 ng/mL for 4 days), were employed to mimic glaucoma condition in vitro. DR disease was reproduced using an ex vivo model of porcine retinal explants exposed to high glucose (HG; 25 mM for 4 days). Results: Results deriving from glaucoma model showed that the deposition of extracellular matrix and the specific protein expression of COL4a1, COL1a1 and ACTA1 were reduced following the HTMCs incubation with hCL engineered with hAFSCs or rhNGF‐MPs. Likewise, in the DR model, the HG‐increased Tumour Necrosis Factor α (TNF‐α) and Nuclear factor erythroid 2–Related Factor 2 (NRF2) levels were reduced following the incubation with hCL engineered with hAFSCs and rhNGF‐MPs. Of note, as demonstrated by the increase of structural (TUBB3 and Rho) and apoptotic (BAX/Bcl2 and p21) markers, a neuroprotective effect of engineered‐hCLs was observed in the DR model. Conclusions: Overall, our results demonstrated that this innovative bio‐engineered scaffold may represent a potential therapeutic approach for posterior ocular diseases treatment. [ABSTRACT FROM AUTHOR]

Aims/Purpose: Retinal neurodegenerative diseases (RND) are associated with a progressive degeneration and death of retinal cells. Recently, mesenchymal stem cells (MSCs) showed a protective role against retinal cells degeneration and apoptosis. However, due to the complexity of such diseases, there is the need to develop in vitro or ex vivo models which allow the study of RND pathogenesis and better understand the regenerative role of MSCs. Therefore, the aim of our study was to use porcine retinas to establish a possible ex vivo model of spontaneous neuroretinal degeneration and employ this model to evaluate the efficacy of human amniotic fluid stem cells (hAFSCs) on retinal cells undergoing damage. Methods: To this end, neuroretinal explants were obtained from pig eyes and placed over the porous membrane of a transwell plate. To induce a time‐dependent spontaneous retinal degeneration, explants were cultured for 24, 48, 72, 96 h, 5 and 8 days. The damage grade was assessed with qRT‐PCR and immunohistochemistry analyses for GFAP and TUNEL‐assay. Then, the explants were co‐cultured with hAFSCs up to 8 days to evaluate their effect on retinal cells death via propidium iodide (PI) staining. Results: Results demonstrated that the cultivation of retinal explants up to 8 days induced an increase in the gene expression of inflammatory (NF‐kB and TNF‐alpha), pro‐apoptotic (p21 and p53) and oxidative stress markers (NRF2). We also observed an increased expression of GFAP and CD11b, suggesting an activation of the microglia and up‐regulation of Müller cells. In addition, the cultivation time induced an increase in the number of apoptotic cells (TUNEL). However, interestingly, the cells death decreased after co‐cultivation with hAFSCs (PI staining). Conclusions: In conclusion, our data demonstrate that the prolonged cultivation of porcine ex vivo retina can induce a time‐dependent spontaneous degeneration able to simulate a model of RND. Of note, the co‐culture preliminary data suggest a protective effects of hAFSCs on retinal cells death. [ABSTRACT FROM AUTHOR]