61. Vascular Smooth Muscle Cell RNA Aptamers for the Treatment of Cardiovascular Disease

Abstract

We demonstrated that this IRES is active in patients expressing the N-truncated dystrophin, raising the possibility of the therapeutic use of this isoform. To explore this we developed a novel out-of-frame exonskipping approach that uses AAV-mediated U7snRNA to efficiently skip exon 2. By injecting this AAV vector into a DMD mouse model carrying a duplication of exon 2 (Dup2), this generates a truncated reading frame, leading to activation of the IRES and synthesis of the N-truncated isoform. We now demonstrate that despite lacking the first half of the canonical actin binding domain 1, this N-truncated protein is highly functional. Intramuscular injection of the AAV1.U7snRNA vector into Dup2 mice results in high levels of expression of the N-truncated isoform by 4 to 6 weeks post-injection, along with complete correction of the physiologic and pathologic features as measured by Evans blue dye uptake, hindlimb grip strength, tibialis anterior specific force, and force correction after eccentric contraction. Preliminary results supports that systemic delivery of AAV9.U7snRNA vector into Dup2 mice induce expression of this functional isoform into all muscle including heart and diaphragm, thereby improving muscle histopathology. Following treatment, a genome-wide normalized RPF-Seq data analysis (Ribosome Protected Fragment) was performed to check if the treatment restored the Haslett gene lists (gene altered in DMD) to a 'non-dystrophic' pattern. Our data clearly indicates that the treatment restored the global expression pattern to a more normal pattern. This level of correction to that of control mice supports the idea that this novel therapeutic approach should be beneficial for the 6% of patients with mutations within the first five exons of DMD.

Photothermal Spongy Film for Enhanced Surface-Mediated Transfection to Primary Cells

“…Previous studies have reported a relative low transfection efficacy to ECs. 50,51 However, high surface-mediate transfection to hard-to-transfect cells has not yet been reported. Our platform reached this highest transfection record based on the surface-mediated approach, which could potentially benefit localized gene therapy such as the gene-eluting stent.…”