Figure 1

Morphology, human minidystrophin expression and ex vivo muscle function analysis of diaphragm muscle. (A) Sections of diaphragm from experimental and control mice were stained with hematoxylin and eosin (H&E) and immunolabeled for minidystrophin (minidys) transgene expression detected with green fluorescence and stained with DAPI to detect nuclei (image bar = 200 µm). (B) Human minidystrophin-expressing muscle fibers were quantified and expressed as an average percentage of the total number of muscle fibers per section. Necrotic and regenerating muscle fibers were identified by binding to mouse immunoglobulin G (IgG) and expression of embryonic myosin heavy chain (eMyHC), respectively, and expressed as the average percentage of the total number of muscle fibers per section. Diaphragms from C57BL/10 healthy control mice lack human minidystrophin expression, necrosis and regeneration (data not shown in B). Ex vivo functional analysis of the diaphragm is shown by specific force production (N/cm²) (C) and as the percent force production in response to 10 isometric lengthening activations (D). All quantitative data are shown as mean ± standard error of the mean (SEM); *significant difference from untreated mdx mice (P < 0.05); n = number of animals analyzed. , C57BL/10; , untreated mdx; , mdx, AAV + NBD peptide; , mdx, AAV + saline.