Experimental Approaches to the Study of A2E, a Bisretinoid Lipofuscin Chromophore of Retinal Pigment Epithelium

Bisretinoid lipofuscin compounds that accumulate in retinal pigment epithelial (RPE) cells are implicated in the pathogenesisof some forms of macular degeneration. In the development of approaches to the amelioration of retinal disorders characterizedby enhanced RPE lipofuscin formation, attention is being given to therapies that reduce the production of these damaging pigments. An understanding of the biosynthetic pathways by which these molecules form is essential to the development of these therapies. Thus methods for studying the biosynthesis of these compounds are presented. A tissue culture model is also described wherebya human RPE cell line that is otherwise devoid of bisretinoid lipofuscin compounds is employed and synthesized A2E is deliveredto the cells. This approach allows for a population of RPE cells that have accumulated the lipofuscin fluorophore A2E in additionto A2E-free cells.