What if we could treat disease, and potentially even cure it, with a single procedure? This is the promise of gene therapy – to correct the underlying genetic cause of disease. While gene therapy has exciting potential, failures in early clinical trials – due to problems with safety and efficacy – highlighted the need to further understand the underlying science of gene therapies. Find out how NanoTemper is helping researchers to develop safer and more effective gene therapies.
Safety and efficacy lead the path forward
Viral vectors — adeno-associated virus (AAV) and lentivirus — and gene editing technologies are key tools in the development of treatments for several diseases like sickle cell anemia, Huntington’s disease, and some types of cancer. To be successful, these therapies must effectively and safely deliver nucleic acids to the target cell. Characterizing the interactions between viral vector or gene-editing proteins and the target cells is one way to tackle the challenge of improving a therapy’s safety and efficacy.
In order to design a good gene therapy vector, researchers must consider not only capsid formation and structure, but also how well it delivers the genetic payload to the cell. Gene therapy optimization requires understanding how much genetic material is loaded into the vector, as well as the mechanism of payload release. Avoiding the loss of DNA or RNA during storage and transport is also a critical concern for those working in scale-up and manufacturing of gene therapy products.
Monitor vector stability and prevent DNA loss in AAVs
Manufacturing a successful gene therapy vector relies on the stability of its capsid. This means not only ensuring the capsids are serotyped properly, but also that none of the genetic material is lost over the course of the manufacturing process. This group used nanoDSF to probe vector stability and relate it to the amount of DNA lost in different storage conditions.
Gene editing technologies
Gene editing technologies can deliver gene therapies via targeted in vivo genome editing – including gene addition, deletion, and correction. In particular, the CRISPR-Cas9 system presents exciting new possibilities for the treatment of genetic disorders. Researchers are now working to make gene editing tools safer by eliminating off-target editing using Cas9 variants or by looking for alternative delivery systems.
Improve gene editing specificity using alternative Cas9 variants
Gene editing with CRISPR-Cas9 has shown great promise in the treatment of diseases such as sickle cell anemia. However, off-target gene editing has been reported for some Cas9 proteins, like SpCas9. This study used MST to show that a different variant of Cas9, FnCas9, has a higher specificity for its intended target and low off-target binding. FnCas9 was then used to successfully correct sickle cell mutations in the patient-derived pluripotent stem cells.
Design a more specific nucleic acid delivery system
The use of viral vectors still raises concerns about safety due to off-target delivery of nucleic acids. To improve target specificity, the authors designed a chromatin-based nucleic acid delivery system that incorporates antibodies specific to cell surface elements. The key to the success of this system is the efficient capture of the antibody to the chromatin, and MST was used to quantify the interaction between different antibodies and the chromatin. This allowed them to find the best antibody for constructing a highly efficient and specific chromatin-based delivery system for CRISPR-Cas9 gene editing.