Fig. 2
Analysis of extracellular vesicle (EV) secretion after intracerebroventricular (icv) injection of Aβ oligomers (AβO). (a) ELISA analysis of soluble Aβ1–42 levels in the cerebrospinal fluid (CSF) of 7 (n = 10) and 40 (n = 15) weeks old APP/PS1 mice. (b) Nanoparticle Tracking Analysis (NTA; NanoSight) quantification of the amount of particles in CSF 2 and 6 h after icv injection of scrambled peptide (black) or AβO (grey) in C57BL/6J mice (n = 4), analyzed using 2-way ANOVA. (c) ExoView analysis of the amount of CD81 captured—CD81 positive and CD9 captured—CD81 positive EVs in CSF 6 h after icv injection of scrambled peptide (black) or AβO (grey) in C57BL/6J mice (n = 6). For each biological replicate, the presented result is the average from three different technical replicates on the chip. (d) NTA (NanoSight) quantification of the particles in the medium of primary CPE cells after 2 h of stimulation with scrambled peptide (black) or AβO (grey) and 24 h of incubation (n = 6). (e) Representative confocal images of ALIX, AnnexinA2 (ANXA2), CD63, Flotillin1 (FLOT1) and RAB5 (red) in the CP 6 h after the icv injection of scrambled peptide or AβO in C57BL/6J mice (n = 3). Cell nuclei are counterstained with Hoechst (blue). The ependymal cells that line the ventricle are indicated by a white line. Scale bar represents 100 µm in the overview images and 10 µm in the zoomed-in images. (f, g) Quantification (f) and representative transmission electron microscopy (TEM) images (g) of CP tissue, isolated from mice 4 h after the icv injection with scrambled peptide or AβO in C57BL/6J mice (n = 2). Amount of multivesicular bodies (MVBs) per cell section and amount of intraluminal vesicles (ILVs) per cell section are displayed. Two regions of 20 CPE cells were manually counted for each biological replicate, resulting in the average amount of MVBs and ILVs in 40 CPE cells per cell section. White arrow heads point to ILVs present in MVBs. Scale bar represents 10 µm in the overview images and 1 µm in the zoomed-in images