Fig. 3.

Overexpression of the miniagrin protein and the improvement of muscle histology in skeletal muscle after systemic AAV-miniagrin gene delivery. The AAV1 vector was injected i.p. in dy^w/dy^w neonates, and the mice were killed at 4 months of age. (a) Agrin staining of diaphragm (first row) and quadriceps (third row) showed overexpression of miniagrin protein after treatment, whereas H & E staining (second and fourth rows, respectively) displayed improved muscle histology. Untreated homozygous mice dy/dy (Left), AAV-treated homozygous mice (dy/dy + AAV) (Center), and littermate WT control mice (Right). (Scale bars: 100 μm.) (b) The untreated dystrophic mice (empty columns) displayed consistently smaller and more variable myofiber diameters. The AAV-miniagrin-treated dy^w/dy^w mice (filled columns) displayed myofibers larger than the untreated mice but smaller than the WT control (hatched columns). In detail, 8- to 10-μm cryo-thin sections of the quadriceps muscles were subjected to IF staining against the dystrophin to display circumferences of the myofiber. Pictures were taken and the radius of the myofiber was analyzed by using metamorph software with a minimum of 300 myofibers from each mouse and three mice for each group. Student's t test was used; *, P < 0.05. Standard error is labeled as a bar.