Cardiac and skeletal muscle delivery of biotherapeutics with a blood vessel epicardial substance-targeting peptide

Although peptide-based delivery strategies show promise for muscle and heart diseases, delivery of biotherapeutics to both skeletal and cardiac muscles remains challenging. Here, we identified a muscle-homing peptide (BV2) against blood vessel epicardial substance (BVES) by phage display. BV2 shows high binding affinity to BVES and is internalized primarily via caveolae-mediated endocytosis. Importantly, BV2 enables efficient delivery of Duchenne Muscular Dystrophy (DMD) phosphorodiamidate morpholino oligomer (PMO), mCherry protein and exosomes to skeletal muscle and heart in vivo. BV2-mCherry protein and BV2-E31R anti-myostatin peptide were effectively delivered to muscle layers when microneedles loaded with these biotherapeutics were implanted on hindlimbs of mice. Muscle mass and myofiber size also significantly increased in muscle atrophy mice grafted with BV2-E31R microneedles. Moreover, significantly enhanced restoration of dystrophin protein was achieved in peripheral and cardiac muscles of dystrophin-deficient mdx and dystrophin/utrophin double-knockout mice when exosomes simultaneously modified with BV2 and PMO. These findings highlight the potency of BV2 in directing targeted delivery of diverse biotherapeutics to muscle and heart, thus providing an effective tool for DMD and other muscular and cardiac disorders.