The retinal pigment epithelium (RPE) is a layer of multipotential cells of neural ectoderm origin lying between Bruch’s membrane and the neural retina. The RPE subserves several essential ocular functions, including phagocytosis of shed photoreceptor outer segments, maintenance of the blood-retinal barrier, absorption of stray light, regulation of the biochemical, metabolic, and ionic composition of the subretinal space, and induction of embryonic differentiation of adjacent neural retina and choroids (1 ). Experimental evidence indicates that early in embryonic life the neural retina can regenerate from the pigment epithelium (2 ). In vitro cultures of pure RPE provide a vehicle for studying RPE function in both normal and diseased states, and may also serve as a model for other neural cells (3 ,4 ). Multiple techniques have been described for culturing human RPE ((5) – (12) ). The authors describe here a modification of the technique of DelMonte and Maumenee (10 ), which is simple and effective in establishing primary cultures and extended cell lines of human RPE for research.
