Figure 4.

Effects of Early Exon-Skipping Treatment on Dystrophin Production in CXMD_J Cardiac Muscles

(A) Representative RT-PCR image showing exon 6–9 skipping across different regions of the heart after treatment with the 4-PMO cocktail. Native, intermediate, and exon-skipped bands for wild-type (WT), non-treated (NT), and treated samples are indicated as in Figure 2. Exon-skipping efficiencies were quantified, as shown below. Error bars, SEM. Dots represent individual dogs. (B) Representative western blot detecting for dystrophin in various cardiac muscles using DYS1. Desmin and myosin heavy chain (MyHC) were used as loading controls. (C) Representative immunohistochemistry images showing an absence of DYS1 dystrophin signal (green) in treated cardiac muscles, either in the myocardium or the Purkinje fiber region; blue, nuclei. Total magnification, 200×; scale bar, 100 μm. For all panels, n = 4 (PMO-treated dogs). Abbreviations: PEV, posterior external left ventricle region; PW, posterior wall of the left ventricle; LV, left ventricle; AP, anterior papillary muscle; PP, posterior papillary muscle; SL, left side of the interventricular septum; SR, right side of the interventricular septum; RV, right ventricle.