Figure 3(A) Confocal immunofluorescence of muscle biopsy from Pt 01 (tibialis anterior post-treatment) stained with anti-dystrophin dys1 antibody (which recognizes protein fragment encoded by exons 26-30, green signal) and anti laminin-2 (to delineate muscle fibers, red signal); dapi identifies nuclei (blue signal). In the left image only anti dystrophin staining is shown. No dystrophin positive fibers were observed.(B) Confocal immunofluorescence of muscle biopsy from Pt 02 (tibialis anterior post-treatment) stained with anti-dystrophin dys1 antibody (green signal) and anti lamininin-2 (red signal); dapi identifies nuclei (blue signal). In the left image only anti dystrophin staining is shown. Some fiber shows mild and discontinuous dystrophin staining.(C) Immunofluorescence of muscle biopsy from Pt 05 taken before (left, gastrocnemius) and after treatment (right, gastrocnemius) stained with anti dystrophin dys2 antibody (which recognizes exon 77-79). The number and intensity of dystrophin-positive fibers is increased in the post-treatment biopsy.(D) Immunofluorescence of muscle biopsy from Pt 06 taken before (left, gastrocnemius) and after treatment (right, gastrocnemius) stained with anti dystrophin dys2 antibody. Few fibers show scattered dystrophin staining, without obvious differences between pre and post-treatment samples.(E) Results of western blot analysis involving dystrophin antibodies dys1, Mandys18 and Manex46e (recognizing respectively exon 26-30, 17-35, and 46), of total protein extracts (20 µg) obtained from post-treatment biopsy specimens of Pt 01 (tibialis anterior muscle); Ct was used as positive dystrophin control. Below, bands corresponding to myosin heavy chain are shown as loading control. No bands corresponding to full length dystrophin were observed. A schematic representation of the deleted portion of the dystrophin and the region recognized by used antibodies is depicted above the western blot.(F) Results of western blot analysis involving dystrophin antibodies Mandys18 and Manex46e, of total protein extracts (10-20 µg) obtained from pre-treatment (performed at time of diagnosis) and post-treatment biopsy specimens of Pt 02 (tibialis anterior muscle); Ct was used as positive dystrophin control. Below, bands corresponding to myosin heavy chain are shown as loading control. One faint band corresponding to full length dystrophin is observed only in the post-treatment samples with both Mandys18 and Manex46e antibodies. A schematic representation of the deleted portion of the dystrophin and the region recognized by used antibodies is depicted above the western blot.(G) Results of western blot analysis involving dystrophin antibodies Mandys106 (recognizing exon 43) and dys1, of total protein extracts (80 µg, following protein concentration by Amicon Ultra-0.5 centrifugal filter devices, Millipore) obtained from pre-treatment and post-treatment biopsy specimens of Pt 05 (gastrocnemius); Ct was used as positive dystrophin control, CtDmd was used as dystrophin negative control. Below, bands corresponding to myosin heavy chain are shown as loading control. Bands corresponding approximately to full length dystrophin are observed in pre and post-treatment samples with both antibodies However, bands in post-treatment sample appeared higher in amount. A schematic representation of the dystrophin point mutation (black vertical bar) and the region recognized by used antibodies is depicted above the western blot.(H) Results of western blot analysis involving dystrophin antibodies Mandys106 and dys1, of total protein extracts (80 µg, following protein concentration by Amicon Ultra-0.5 centrifugal filter devices, Millipore) obtained from pre-treatment and post-treatment biopsy specimens of Pt 06 (gastrocnemius); Ct was used as positive dystrophin control. Below, bands corresponding to myosin heavy chain are shown as loading control. Bands corresponding approximately to full length dystrophin are observed in pre and post-treatment samples with both antibodies Bands in pre-treatment sample appeared higher in amount as compared to post-treatment sample. A schematic representation of the dystrophin point mutation (black vertical bar) and the region recognized by used antibodies is depicted above the western blot.