Figure 2.

Vector strategy and biodistribution

(A) An expression construct composed of two inverted terminal repeat (ITR) sequences, a muscle-specific CK8 promoter,²³ a microdystrophin cDNA, and a poly(A) tail (pA) (A) was packaged into an AAV9 vector. (B and C) The AAV9-CK8 microdystrophin vector was injected into 7-week-old mice via tail vein to replace (B) absent full-length dystrophin in mdx muscle fibers with (C) microdystrophin. (D) AAV9-microdystrophin blood concentration in treated mice 30 min after injection via tail vein and still present 22 weeks post-treatment. (E) AAV9-microdystrophin was present in heart, diaphragm, quadriceps, gastrocnemius, and EDL muscles at the conclusion of the study. There was no significant difference between groups. Dashed line indicates the lower limit of quantification in (D) and (E).