Left hemi brains were cut into 30μm free-floating coronal sections using an HM 430 freezing-sliding microtome. Sections were stored in cryopreservative buffer (30 % sucrose / 30 % ethylene glycol in 1X PBS) at −20 °C. The day of the experiment, five comparable coronal sections, including the dorsal hippocampus, were collected for each mouse (bregma −1.06 to −2.30). Sections were washed 3 times in TBS buffer for 5 minutes and then incubated in 16mM glycine / 0.25% triton TBS solution for 1 hour at room temperature. After 3 x 5 minute TBS washes, sections were incubated in 5% donkey serum / 0.25% triton TBS solution for 1 hour. Sections were incubated overnight at 4 °C with primary antibodies diluted in 1% BSA / 0.25% triton TBS solution (1% BSA buffer) (Table 1 ). The following day, sections were rinsed 3 x 10 minutes in 1% BSA buffer. Secondary antibodies in 1% BSA buffer were added to the sections for 1 hour at room temperature in the dark (Table 2 ). After 3 x 5 minute TBS washes, sections were mounted on diamond white glass microscope slides (cat # 1358W, Globe Scientific Inc.) using Prolong Gold antifade reagent (cat #P36930, Invitrogen) and 24 x 40mm No 1.5 gold seal cover glasses (cat # 3421, Thermo Scientific).
Aβ (3D6) and LAMP1 staining (Fig. 2 ) were performed on the same sections. Staining for IBA1 and CD68 were performed on a separate set of sections together with 3D6.
Aβ (3D6) and LAMP1 staining (