Figure 3. Representative flow cytometry data Counts to right of arrow represent population of ARPE-19 containing fluorescein isothiocyanate-labeled rod-outer- segments. The area under the curve to the right of the arrow is greater in retinal pigment epithelium cultured on younger Bruch’s membrane (top panel, from a 14-year-old donor) than on older Bruch’s membrane (bottom panel, from a 76-year-old donor).