Figure 9.

Neutrophil counts in TgCRND8 AD mice following biweekly FUS+MB BBB treatments. To evaluate whether neutrophils recruited to the brain due to FUS+MB BBB treatments aid in Aβ plaque clearance, animals from the TgCRND8 mouse model of AD were administered 3 to 5 biweekly treatments. Neutrophils were grouped by whether they contained phagocytosed Aβ, based on colocalization of Ly6G (neutrophils) and 6F3D (Aβ). The skull remained intact in these experiments. (A) Colocalization of MPO and 6F3D was used to determine whether neutrophils contained phagocytosed Aβ. Examples of neutrophils with (top) and without (bottom) phagocytosed Aβ are shown. (B) Neutrophils were counted within the hippocampi and cortices, which were within the focal zone of the transducer used. Sections were stained with MPO (magenta) for neutrophils, 6F3D (white) for Aβ plaques, DAPI (cyan) for nuclei, and GFAP (green) for astrocytes. (C) The number of neutrophils with and without phagocytosed Aβ found in FUS+MB treated animals ('TgFUS') was similar to that found in control animals ('TgCTL'). Scale bars: (A) 20 µm, (B) 500 µm. GFAP: glial fibrillary acidic protein, MPO: myeloperoxidase. Boxplots show median, and upper and lower quartiles.