Table 1.
Summary of clinical and pathological findings of BMD patients with rimmed vacuoles.
Table 2.
Summary of clinical and pathological findings of BMD patients without RVs (DMD deletion exons 45–47 and 45–48).
Figure 1.
Pathological Characteristics of BMD patients. A:
On mGT staining, RVs are seen in the periphery of myofibers (arrow). B: On H&E staining, there is marked variation in fiber size with scattered small atrophic fibers. C: High acid phosphatase activity is seen in the areas of RVs. D: On ATPase staining pre-incubated at pH 4.6, RVs are seen in both type 1 and type 2 fibers. Asterisks indicate myofibers with RVs. Scale bar: 25 µm.
Figure 2.
Immunohistochemical characteristics of RV in BMD compared to DMRV and sIBM.
Representative transverse serial sections of biopsied skeletal muscles from BMD with RV (left column), DMRV (center column) and sIBM (right column) patients. A–C: mGT staining similarly highlights the fibers with RVs (arrowheads) in all patients. D–F: LAMP-1 (red) co-stained with caveolin-3 (green), G–I: LC3, J–L: APP, M–O: Aβ1-42, P–R: polyUb proteins, and S–U: p62. Immunofluorescent signals are observed around RVs (arrowhead). Scale bar: 25 µm.
Figure 3.
Patterns of immunohistochemical findings in BMD with RV.
Representative transverse serial sections of biopsied skeletal muscles from BMD patients with RV. A–C: mGT shows the presence of RVs (arrowheads). D–F: LC3, G–I: Aβ1-42, J–L: polyUb, and M–O: p62. Immunofluorescent signals are seen within the fibers with RVs (arrowheads). Pattern 1 (left column) shows similar characteristic staining of RV fibers as DMRV and sIBM. Pattern 2 (center column) show almost similar characteristics as pattern 1, except for the faint staining of Aβ1-42. Pattern 3 (right column), with rare occurrence, shows myofibers with RVs that are negatively stained by LC3 and Aβ1-42. Scale bar: 25 µm.
Figure 4.
Areas of RVs in BMD myofibers show typical electron microscopic characteristics of autophagic vacuoles. A:
Accumulation of autophagic vacuoles (arrowheads), various cellular debris, and multilamellar bodies (arrow) are seen in myofibers of some BMD patients. Note the intact arrangement of myofibrils (MF) surrounding autophagic area. B: In areas with or without autophagy, lipofuscin deposit (L) is seen. Scale bars: 1 µm.