Figure 6.
Hs3st1 knockout inhibits the binding and uptake of ApoE in an isoform independent fashion. (A) Hs3st1−/− cells show a highly significant reduction in ApoE cell surface binding compared to wild type Ndst1f/f MLECs. Following fixation and incubation with biotinylated ApoE (1000 ng/mL, 100 μL/well) for 90 minutes at RT, cell surface bound ApoE was measured following incubation with streptavidin-HRP and color development. (B) The internalization of fluorescently labeled ApoE is significantly reduced by knockout of Hs3st1, demonstrating the role of 3-O-S in ApoE uptake. (C) Representative confocal microscopy images of ApoE internalization experiments graphed in panel B. ApoE3 is visualized via fluorescence at 488 nm, nuclei are stained blue with DAPI. Scale bars are 20 μm. Error bars are ± SEM.