Figure 5.

Restoration of dystrophin expression after two-week systemic delivery of PMO with PQs in mdx mice (aged 4–5 weeks). Each mouse was injected with 1 mg PMOE23 with and without PQs (0.5 mg). (A) Dystrophin was detected by immunohistochemistry with rabbit polyclonal antibody P7 against dystrophin. Blue nuclear staining with DAPI, and original magnification: ×100. (B) Percentage of dystrophin-positive fibers in different muscle tissues (mean ± SEM, n = 5, two-tailed t-test, *p ≤ .05 compared with 1 mg PMO only). (C) Detection of exon 23 skipping by reverse transcription polymerase chain reaction. Total RNA of 100 ng from each sample was used for amplification of dystrophin mRNA from exon 20 to exon 26. The upper bands correspond to the normal mRNA, and the lower bands correspond to the truncated mRNA with exon E23 skipped. (D) Western blots demonstrate the expression of dystrophin protein from treated mdx mice in comparison with C57BL/6 and untreated mdx mice (20 μg of total protein was loaded for PQ-formulated PMO, PMO-treated mice, WT C57 and control mdx. A: TA; I: Diaphragm; J: Heart). Dystrophin detected with monoclonal antibody Dys 1. α-Actin was used as the loading control.