Abstract
Abstract: :
Purpose: Transplantation of pigment epithelial cell suspensions for the treatment of AMD has not proven useful for recovery of vision, suggesting that the transplanted cells do not acquire proper morphological, positional and functional characteristics. To provide a functional transplant, we have cultured IPE and RPE cells on an ultra thin biodegradable collagen membrane that should provide informational cues allowing the cells to acquire proper morphological and functional characteristics. Methods: Human RPE cells were cultured to confluence on 10 µm thick collagen type I membranes. Using immunocytochemical analysis the confluent cell monolayers were examined for the presence of tight junctions and the expression of a number of differentiation proteins as well as for phagocytic activity. Results: RPE cells cultured on the collagen membrane form an intact polarized monolayer with well–formed tight junctions as evidenced by ZO–1 expression, and express cytokeratin 8, ß–actin, αVß3 integrin as well as cathepsin D indicating appropriate cellular differentiation. Phagocytic activity of the cells grown on the collagen membrane was 10 to 20 fold higher than that of cells cultured on a plastic substrate. Conclusions: PE cells cultured on a 10 µm thick collagen membrane form differentiated monolayers and exhibit functional characteristics that should be useful as subretinal transplants for the restoration of vision in AMD patients.
Keywords: age–related macular degeneration • transplantation • retinal pigment epithelium