Fig. 4. Intraperitoneal systemic delivery of ABE system rescues dystrophin expression and muscle function in neonatal mice.

a Schematic of intraperitoneal injection of AAV particles. AAV-ABE2 was injected intraperitoneally (IP) into postnatal-day-3 (P3) DMD^{ΔmE5051,KIhE50/Y} mice. Some DMD^{ΔmE5051,KIhE50/Y} mice were injected with saline as mock-treated controls. Black arrows indicate time points for tissue collection after IP injection. b Measurement by deep sequencing of splicing site editing efficiency in tibialis anterior (TA), diaphragm (DI), and heart after systemic delivery. RT-PCR products from muscle of DMD^{ΔmE5051,KIhE50/Y} mice were analyzed by gel electrophoresis (c) and deep sequencing (d) to validate exon skipping efficiency. e Western blot analysis shows restoration of dystrophin expression in the TA, DI, and heart of DMD^{ΔmE5051,KIhE50/Y} mice 6 weeks after injection. Dilutions of protein extract from WT mice were used to standardize dystrophin expression (25%, 50% and 75%). Vinculin was used as the loading control. f Immunohistochemistry for dystrophin in TA, DI, and heart of DMD^{ΔmE5051,KIhE50/Y} mice was performed 6 weeks after IP injection. Dystrophin is shown in green. Scale bar, 100 μm. Rotarod rod running time (g) and forelimb grip strength (h) was measured two days in WT, DMD^{ΔmE5051,KIhE50/Y} mice, and DMD^{ΔmE5051,KIhE50/Y} mice treated with ABE2 particles. i The remaining strength was also measured during 7 repetitions test at 10-s intervals. Each dot represents an individual mouse. Data are presented as mean ± s.d (n = 8 independent biological replicates). Significance is indicated by an asterisk and determined using the one-way ANOVA multiple comparison test. *P < 0.05. **P < 0.01. ***P < 0.001. ****P < 0.0001, Ns represents not statistically significant. Source data are provided as a Source Data file.