The Interaction of Indocyanine Green with Human Retinal Pigment Epithelium

Abstract

Cultured human RPE cells take up ICG dye. ICG uptake by RPE cells may involve active transport, as cells incubated with ouabain for 24 hours showed no reduction in cell viability but exhibited reduced infrared fluorescence. The paradoxical increased uptake of ICG into the cells after more prolonged exposure to ouabain may be due to ICG's movement through the damaged cell membrane. Fluorescence due to ICG uptake by RPE has clinical relevance in that it contributes to the fluorescence patterns observed in ICG angiography.