Fig. 4.

Ultrastructural analysis demonstrates the intracellular accumulation of organelles with lysosome-like morphology at amyloid plaques. (A) Electron micrograph of APP/PS1 cerebral cortex tissue showing a central extracellular amyloid deposit (outlined in dashed red line) surrounded by electron-dense organelles (outlined with dashed green line). (Scale bar: 10 µm.) (B) Higher magnification of the boxed region from A reveals the lysosome-like morphology of organelles that accumulate within cellular processes that contact the amyloid plaque. (Scale bar: 2 µm.) (C) Schematic diagram depicting lysosomal accumulation within swollen cellular processes that surround an extracellular β-amyloid deposit.