Perspectives in using gene therapy for lysosomal storage diseases

Conceptually, lysosomal storage disorders (LSDs) are highly amenable to gene transfer therapies because they are monogenic and most of them can benefit from cross-correction. However, past gene transfer clinical trials for LSDs, utilizing focal delivery approaches to the brain for Batten disease and Canavan disease, have provided minimal therapeutic benefit to patients. Recent advancements in vector technology now allow for broad central nervous system and/or peripheral organ gene transfer via in vivo and ex vivo approaches, and the application of these technologies has shown considerable promise in small and large animal preclinical studies. Innate and adaptive immune responses pose a risk for the safety and efficacy of gene transfer in some human populations. This review discusses recent gene therapy advancements, other treatment options, and the risks and obstacles associated with the different therapeutic approaches for LSDs. The objective is to provide an introductory summary of where the field of gene therapy currently stands in the treatment of LSDs, and the directions the field is moving toward. Based on results in animal models, global gene transfer has the potential to profoundly alter the course of LSDs. Moreover, these newer approaches are scalable to large animals and presumably humans.