| Popis: |
Gene therapies for muscle diseases such as Duchenne muscular dystrophy, limb girdle muscular dystrophy, and myotubular myopathy are currently in clinical trials, while numerous additional diseases have gene therapy treatments in development. The primary vector used for these treatments is adeno-associated viral vector (AAV). Unfortunately, basic AAV biology in muscle is poorly understood, which can lead to disconnects between preclinical studies meant to develop effective treatments and the clinical trials meant to test their efficacy. Specifically, a lack of a model illustrating the relationship of vector DNA, RNA and protein over time in muscle has led to some preclinical studies inappropriately using RNA as a surrogate for protein expression at early time points. It has also resulted in clinical trial designers having to somewhat blindly choose timepoints for their patient muscle biopsies in an attempt to balance a need for early data and a desire to demonstrate efficacy, but without the data to inform their decisions. Additionally, preclinical studies and clinical trials often use different vector preparation methods due to preclinical time and cost restrictions and clinical safety standards. However, we have previously demonstrated that these more stringent purification methods used in clinical settings can adversely affect dose efficacies by removing empty capsids. Here, we propose to build the needed models relating DNA, RNA and protein in striated muscles after AAV gene therapy and to determine the mechanisms through which empty capsids can increase expression. With these data, the field will have new paradigms off of which to build their preclinical and clinical studies, increasing the stringency with which AAV gene therapies are developed and assessed in model organisms and human patients. |
