Limp-2 immunostaining in the hippocampus of MPS IIIA mice treated with PPS. Panels (a, b) show representative images from 32-week-old, sham treated MPS IIIA mice, and panels (c, d) show representative images from group 1 treated mice of the same age. Panels (e, f) show representative images from 16-week-old sham treated MPS IIIA mice, and panels (g, h) show images from mice of the same age treated by ICV infusion. The boxes in panels (a, c, e, and g) show the areas of magnification