Figure 3

Immunofluorescence microscopy of RPE flatmouts. (A-C) Dissected RPE flatmounts from a control and treated with CILE of APPsw/PS1 bigenic mice were stained with 6E10 IgG for Aβ (red). (D-F) RPE flatmounts were double-stained with 6E10 IgG for Aβ (green) and rhodamine-conjugated phalloidin for F-actin (red) and visualized by confocal microscopy. Druen-like Aβ deposits and vessel-like structures are evident in the mice following 6-month CILE (F). (G-H) Fluorescent microscopy reveals normal morphology of RPE cells by phalloidin staining (red) in the control (G) and increased defects of RPE morphology (white circles) in mice received CILEs (H & I). (J-L) Fluorescent immunoreactivity of IBA-1, a molecular marker for microglia, shows markedly increased number of microglia and microglial dendritic staining (green) in RPE from the mice following CILEs (K & L) compared with the control (J). Cell nuclei are counterstained blue by 4'-6-diamidino-2-phenylindole (DAPI). Scale bars = 20 μm for (A-C), 40 μm for (D-L). (M-P). Quantifications of Aβ deposits (M), RPE morphological defects (N), infiltration of microglia (O), and the length of microglial dendrites. Bars depict mean ± SEM. *: P < 0.001 (N = 8).