1. Fig. 6. Microglial phagocytosis and lysosomal uptake of Aβ induced by SUS treatment.
Microglial phagocytosis and lysosomal uptake of Aβ induced by SUS treatment. (A and B) Plaques in sham-treated animals were surrounded by lysosomal CD68-positive microglia that contained some Aβ. (C and D) In contrast, plaques in SUS-treated mouse brains were surrounded by microglia that contained significantly more Aβ in their lysosomal compartments, with some plaques appearing to be completely phagocytosed by microglia. (E) A twofold increase in microglia-internalized Aβ was observed in SUS-treated compared to sham-treated mouse brains (unpaired t test, P = 0.002). (F to I) Plaques imaged at high magnification in 3D. CD68 labeling revealed the extent of Aβ at the plaque site that was internalized by microglia into lysosomes. 4′,6-Diamidino-2-phenylindole (DAPI) was used to visualize nuclei. (J) Confocal analysis of Aβ and CD68 revealed that 6 of 8 SUS-treated mice and 0 of 8 sham-treated mice had “cleared plaques” in cortical areas, with Aβ being almost completely within microglial lysosomes (Fisher’s exact test, P = 0.007; n = 8 per group, with four sections analyzed in each case). Scale bars, 100 μm (A and C) and 10 μm (B, D, and F to I).
Gerhard Leinenga and Jürgen Götz Sci Transl Med 2015;7:278ra33
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