Fig. 6

Vacuoles may contain very large lysosomes. a. Acid phosphatase-stained muscle sections from two representative patients demonstrates positive vacuoles (asterisk) suggestive of large lysosomes, while other vacuoles remain acid phosphatase negative (black arrowhead). b. The lysosomal marker LAMP2 can been seen prominently in some vacuoles consistent with the acid phosphatase positive vacuoles. Laminin α2 (merosin) and dystrophin (LNα2 & DYS in green) were used to demonstrate the sarcolemma while DAPI (blue) was used to demonstrate nuclei. c. Sections from three representative patients (P1-3) and a control demonstrate very large LAMP2-positive vacuoles (white asterisk), which are absent in the control. In addition, an invagination leading to a LAMP2-positive vacuole is evident in patient 2 (white arrowhead). Bar is 50 µm