Immunohistochemical staining for lysosomes within capillary endothelium in cerebellum of MPS III patients. (A, C) Cerebellum control tissues contained capillaries with little lysosomal immunoexpression (arrows, green). A morphologically normal Purkinje cell with its dendrites was seen (C). Increasing LAMP-1 immunoreactivity within capillary endothelium was determined in cerebellum of (B) MPS III A (green, arrows) and (D, E) MPS III D (green, arrows). Arrows and arrowheads indicate LAMP-1 (green) and collagen IV (red) immunoexpressions, respectively. Magnification in A-E is 40x. (F) Semi-quantitative analysis of LAMP-1 immunoreactivity showed similar high lysosomal marker expressions within capillary endothelium in MPS III A and III D cerebellums vs. controls.