FIGURE 2.

LDLR overexpression enhances the uptake and clearance of Aβ by primary astrocytes. Primary astrocytes from either WT or LDLR transgenic mice were incubated with soluble (A) Aβ40 or (B) Aβ42 (2 μg/ml) for 3 h at 37 °C. The cells were then washed with PBS, incubated with trypsin to remove cell surface bound Aβ, and lysed in Triton X-100 lysis buffer. The cell-internalized Aβ was then assessed by ELISA. Mean ± S.E. (n ≥ 4), *** denotes p < 0.001. C, immunoblot analysis for Aβ was also performed on the cell lysates. Representative images are shown. Aβ clearance was assessed by the addition of either (D) Aβ40 or (E) Aβ42 (2 μg/ml) to the media of primary astrocytes. After 24 h, the levels of Aβ remaining in the medium along with the starting amount of Aβ were measured by ELISA. Mean ± S.E. (n ≥ 4), * denotes p < 0.05, *** denotes p < 0.001.