Fig. 5. Vacuoles in the hVps34 KD cells are acidic and receive traffic from the endocytic compartment. (A) Control and hVps34 KD cells were incubated with 2.5 µg/ml Acridine Orange (AO) for 30 minutes. The cells were then examined by fluorescence microscopy using green (excitation wavelength: 465-495 nm; emission wavelength: 515-555 nm) and red (excitation wavelength: 528-553 nm; emission wavelength 600-660 nm) filters. Red fluorescence emanates from AO in acidic compartments. Bar, 10 µm. (B) Control and KD cells were incubated with 500 µg/ml Texas Red (TxR)-dextran for 16 hours. Following incubation for 2 hours, cells were fixed and co-stained with a monoclonal antibody against LAMP1. Arrows indicate vacuoles containing both LAMP1 and TxR-dextran. Arrowheads point to vacuoles lacking TxR-dextran. Bar, 10 µm.