Figure 3. Presence of A2E in the lysosomal fraction of multiple 1 µM A2E-treated ARPE-19 cells compared to untreated ARPE-19 cells. A: A2E fluorescence (ex 485/ em 535) was measured in lysosomal fractions prepared with gradient ultracentrifugation. B: Lysosomal-associated membrane protein 1 (LAMP1) lysosomal marker expression in immunoblots of the same fractions was probed with the LAMP1 primary antibody.