FIG. 4.

Histopathological studies 6 weeks postinjection. Semi-thin sections of different brain areas surrounding the injection point were stained with toluidine blue to highlight the enlargement of vacuoles containing lysosomal storage material as seen in PBS-treated MPS VII mice. Representative images from (a) cortex, striatum, and meninges in MPS VII PBS (left), MPS VII HD-RIGIE (middle), and WT mice (right) at injection area, and at more distal areas (b), slices in S3 (left panel) and S4 (right panel), and (c) hippocampus. HD-RIGIE-treated mice show a pattern similar to WT animals in all tissues analyzed. Quantification of corrected cells is described in Table 1. Scale bar=20 μm. Black and white arrows indicate vesicle accumulation in glial cells and neurons, respectively.