Cytoplasmic Changes with Chloroquine in ARPE-19. Phase contrast microscopy of ARPE-19 with 0 (A), 10 (B), 20 (C), 40 (D), 80 (E) μg/ml chloroquine. Chloroquine treatment causes membrane-enclosed vacuoles (red arrows) and membranous dense bodies (blue arrows). ARPE treated with high chloroquine dosage show signs of cell death. Bar size = 25 microns.