Figure 1. (a) Scattered, angulated and rounded, atrophic fibers (H&E, cryostat section). (b) Large numbers of necrotic and basophilic regenerating fibers (H&E, paraffin section). (c) Necrotic fibers occurring singly and in small groups, many showing myophagocytosis (H&E, cryostat section). (d) Small numbers of CD8+ T lymphocytes, mostly confined to perivascular locations (CD8 immunohistochemistry). (e) Macrophages within necrotic fibers (CD68 immunohistochemistry). (f) Patchy sarcolemmal upregulation of MHC class I antigen (MHC class I immunohistochemistry).