Lysosomal compartment size is significantly increased in MPS brain and localises to neurons and microglia.

<p>Lysosomal compartment size was measured by quantifying LAMP2 immunohistochemical staining of WT, MPSI, IIIA and IIIB mouse cerebral cortex at 4 and 9 months of age (4 m and 9 m; n = 3 mice per group). (A) Four sections of brain from Bregma 0.26, −0.46 −1.18 and −1.94 mm were stained concurrently. (B) Representative sections stained with LAMP2 that correspond to a whole field of view covering cortical layers II/III–VI (Section 2a in A). Bars = 100 µm. (C) Two fields of view (boxed areas in A; ×20 objective) from each section were quantified using ImageJ. Error bars represent the SEM and p values are from two way ANOVA with Tukey's multiple comparisons test. Significant overall genotype differences are denoted by thick black lines. Individual genotype*time differences are shown by thin green lines. The significant individual genotype*time differences (p<0.001) between all MPSs and WT at each time point are not shown for clarity. (D) LAMP2 (green) was detected in NeuN-positive neurons (red) and in ILB4-positive microglia (red) in layer II/III of WT, MPSI, IIIA and IIIB cerebral cortex. Nuclei are stained with DAPI (blue); Bar = 10 µm. Single colours and overlays are shown in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0035787#pone.0035787.s001" target="_blank">Figure S1</a>.