UCLA researchers in the Department of Pediatrics, Hematology/ Oncology have constructed a nanoparticle toolkit for increased integration and reduced toxicity for gene therapies that treat debilitating diseases such as Cystic Fibrosis and other critical genetic diseases.
BACKGROUND: Gene therapies are the forefront of therapeutic advancements as a one-off treatment for many debilitating diseases. However, delivery and insertion of the therapeutic transgene are major hurdles that must be solved to effectively implement gene therapy solutions. Specifically, CRISPR-Cas 9 mediated gene editing poses safety risks upon integration into an off-target location due to long homology arms of Homology Directed Repair (HDR). Additionally, effectively delivering gene therapy molecules to certain tissue locations poses another challenge. For instance, in the case of the disease Cystic Fibrosis (CF), it’s difficult to deliver biomolecules to airway epithelial stem cells due to the physical barriers (thick mucus and epithelial tight junctions) imposed by the CF airway. Thus, there’s a high need for improvement in HDR efficiency, safety, and delivery of nanoparticles to stem cell populations, especially in the epithelium.
INNOVATION: A multidisciplinary UCLA research team led by Dr. Steven Jonas, Dr. Brigitte Gomperts, and Dr. Donald Kohn have produced gene editing materials for reduced off-target effects and optimal gene integration. Researchers chemically modified and shortened dsDNA to decrease toxicity while maintaining integration efficiency. Validation experiments demonstrated a two-fold increase in integration and cutting efficiency in epithelial cell lines of chemically modified dsDNA compared to unmodified dsDNA. The team additionally constructed a lipid nanoparticle platform (LNP) to enable gene therapies for the disease Cystic Fibrosis. This technology is made up of two components: epithelial penetrating nanoparticles (epNPs) and CRISPR nanoparticles (crNPs). The disruption of epithelial airway by epNPs allows for effective delivery of gene editing molecules to stem cells. The combination of epNPs and crNPs shows successful delivery to epithelial cells resulting in gene editing of CTFR locus, the Cystic Fibrosis mutated gene.
POTENTIAL APPLICATIONS:
- Gene editing and delivery toolkit for Cystic Fibrosis
- Gene editing and delivery toolkit for other genetic diseases
ADVANTAGES:
- Reduced off-target effects of gene insertion
- Two-fold increase in gene integration and cutting efficienc
- Increased penetration in diseased epithelial tissue
DEVELOPMENT-TO-DATE: CTFR gene (the Cystic Fibrosis mutated gene) was corrected successfully in human epithelial cell lines.
Keywords: Gene therapy, homology directed repair, cystic fibrosis, gene delivery, platform technology, nanoparticles, rare diseases, genetic diseases