Clinical potential of microdystrophin as a surrogate endpoint

Basic notions about gene therapy from the nucleic acid perspective and applications in a pediatric disease: Duchenne muscular dystrophy

Gene therapy involves the introduction of genetic material into cells as a therapeutic molecule to cure a disease. Through the transfer of specific nucleic acid to the target tissue, gene expression can be downregulated, augmented, or corrected thanks to the nucleic acid sequence as a support of gene expression. This is achieved through molecular interactions according to the sequence arrangement or the secondary structure of the molecules or through their catalytic properties. Over the past two decades, the rapid advances of knowledge and technologies in gene therapy have led to the development of different strategies and to the extension of its use to numerous indications, including certain cancers. Major success has been achieved in clinical trials and the field of gene therapy is booming. Several gene therapy products are now on the market in Europe, the United States, and China. In this review, we cover the basic principles of gene therapy and the characteristics of the main vectors used to transfer genetic material into the cell. As an example of applications, we address the various strategies applied to a rare pediatric muscle disease: Duchenne muscular dystrophy. © 2023 Published by Elsevier Masson SAS on behalf of French Society of Pediatrics.

Evolution and developmental functions of the dystrophin-associated protein complex: beyond the idea of a muscle-specific cell adhesion complex

The Dystrophin-Associated Protein Complex (DAPC) is a well-defined and evolutionarily conserved complex in animals. DAPC interacts with the F-actin cytoskeleton via dystrophin, and with the extracellular matrix via the membrane protein dystroglycan. Probably for historical reasons that have linked its discovery to muscular dystrophies, DAPC function is often described as limited to muscle integrity maintenance by providing mechanical robustness, which implies strong cell-extracellular matrix adhesion properties. In this review, phylogenetic and functional data from different vertebrate and invertebrate models will be analyzed and compared to explore the molecular and cellular functions of DAPC, with a specific focus on dystrophin. These data reveals that the evolution paths of DAPC and muscle cells are not intrinsically linked and that many features of dystrophin protein domains have not been identified yet. DAPC adhesive properties also are discussed by reviewing the available evidence of common key features of adhesion complexes, such as complex clustering, force transmission, mechanosensitivity and mechanotransduction. Finally, the review highlights DAPC developmental roles in tissue morphogenesis and basement membrane (BM) assembly that may indicate adhesion-independent functions.