FIGURE 4.

LDLR facilitates Aβ trafficking to lysosomes through a similar pathway as lipoprotein particles. A, to demonstrate that increasing LDLR levels promotes the transport of Aβ in similar vesicles as lipoprotein particles, WT and LDLR Tg primary astrocytes were incubated with fluorescent Aβ42 (3 μg/ml) and DiI-LDL (0.5 μg/ml) for 3 h at 37 °C. The cells were then washed and imaged using confocal microscopy. Overlap of Aβ and the DiI-LDL signal was observed in the LDLR Tg cells. B, to observe Aβ uptake into lysosomal compartments, WT and LDLR Tg primary astrocytes were incubated with fluorescent Aβ42 (2 μg/ml) for 3 h at 37 °C. The cells were then washed and 50 nm LysoTracker was added to the cells for 15 min. The cells were then washed again and imaged using confocal microscopy. C, colocalization of the Aβ and LysoTracker signal was analyzed and quantified. Mean ± S.E., *** denotes p < 0.001. Error bar represents 10 μm.