Interaction of VH4127 conjugates with hLDLR and comparison with ApoB and ApoE peptides.

<p>Representative confocal fluorescence micrographs of CHO-hLDLR-GFP cells incubated with 10 μM of VH4127-Cy5.5 (light blue) and 20μg/mL of DiI-LDL (red). Insets correspond to higher magnification of boxed cells. (B) CHO-hLDLR-GFP cells incubated with 10 μM of VH4Sc-Cy5.5 and 20μg/mL of DiI-LDL (red). (C) CHO-hLDLR-GFP cells incubated with 10μM of VH4127-siGLO Cyclophiline B (red). (D) CHO-hLDLR-GFP cells incubated with 10μM of VH4127-S-Tag (light blue) following S-Tag detection with a goat anti-S-Tag and a secondary A647-conjugated anti-Goat antibody. Cell nuclei are labeled with Hoechst#33258 (blue). Co-labeling appears in yellow in the merged pictures. Note that all conjugates bind and largely co-localize with LDLR. (E) ELISA quantification of bound/endocytosed VH4127-S-Tag or VH4Sc-S-Tag conjugates to CHO-hLDLR-GFP cells 1 hr post-incubation at 10μM. The graph represents the mean of concentration in nM ± SD (n = 3 per conjugate, *p ≤ 0.05, **p ≤ 0.01, ***p ≤ 0.001). (F) Image J quantification of the percentage of co-localization ± SD (n = 3 per peptide) between hLDLR-GFP (blue graph bars) or hTfR-GFP (orange graph bars) and ApoB, ApoE1, ApoE2 and VH4127 peptides conjugated to the S-Tag (*p ≤ 0.05, **p ≤ 0.01, ***p ≤ 0.001). The percentage of co-localization on the hLDLR-GFP (blue graph bars) between the ApoB, ApoE1 and ApoE2 peptides conjugated to the S-Tag was also compared to that of VH4127-S-Tag (### p ≤ 0.001).