Fig. 3

Characterization of microglial αS inclusions in symptomatic αS TG mice. (a) Schematic of αS showing the N-terminal region (light green) with PD-linked mutations A30P (blue) and A53T (red), NAC domain (light orange) and C-terminus (light blue) with four phosphorylation sites (purple). Black lines indicate the epitopes of antibodies specific for the N-terminus (34–45), NAC domain (80–96), C-terminus (177–122), and p-αS (phosphorylated αS at serine 129) that were used for immunofluorescence staining. (b-e) Co-immunofluorescence staining for Iba1 (red) and epitope-specific αS antibodies (green) in the brainstem of terminally ill Thy1-h[A30P]αS. (b) Section of Iba1-positive microglia with 34–45-positive αS aggregates. Note that most Iba1-positive cells are also labeled with anti-αS antibody. Complete overlapping signal of Iba1 and anti-αS 34–45 antibodies in the enlarged images. (c) Section of Iba1-positive microglia with 80–96-positive αS inclusions. Note that most Iba1-positive cells are co-localized with anti-αS antibody. Complete overlapping signal of Iba1 and anti-αS 80–96 antibodies in the enlarged images. (d) Section of Iba1-positive microglia and 117–122 anti-αS antibody. Note that most Iba1-positive cells are devoid of 117–122 anti-αS antibody staining. A rare occasion with partial overlap of Iba1 and 117–122 anti-αS signal is demonstrated in the enlarged images suggesting microglia phagocytosing αS-positive structure. (e) Section of Iba1-positive cells labeled with p-αS antibody. Note that most of the Iba1-positive cells are p-αS-negative. Similar to (d), a rare occasion with partial overlap of Iba1 and anti-p-αS signal is demonstrated in the enlarged images suggesting microglia phagocytosing αS-positive structure. Scale bars, 50 μm and 20 μm (enlarged images)