Combinatorial design of nonviral base editing systems for treating cystic fibrosis with nonsense mutations

PROJECT SUMMARY Cystic fibrosis (CF) is a debilitating genetic disorder that predominantly impacts the lungs and pancreas due to mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. Specifically, nonsense mutations, which produce truncated, non-functional proteins, account for approximately 11% of all CF cases.

Currently, these mutations lack targeted, effective therapeutic solutions. Our research endeavors to address this unmet clinical need by harnessing the capabilities of adenine base editors (ABEs) to correct premature termination codons (PTCs) through translational readthrough, thereby restoring functional protein expression.

To facilitate efficient delivery, we aim to formulate lipid nanoparticles (LNPs) specifically engineered for pulmonary ABE delivery. The project is segmented into three pivotal objectives: 1) the chemical refinement of RNA-encoded ABEs to achieve optimal on-target gene-editing; 2) the development and fine-tuning of LNP

formulations to overcome challenges intrinsic to pulmonary delivery; and 3) comprehensive in vivo validation using a CFTR nonsense mutation mouse model to assess both therapeutic efficacy and safety profiles. By focusing on nanoparticle-mediated lung cell engineering, our approach lays the foundation for a groundbreaking,

non-viral base editing platform that could revolutionize treatment protocols for CF and other diseases stemming from PTCs. Employing cutting-edge methodologies, including the optimization of mRNA sequences encoding ABEs, gRNA design, and novel four-component combinatorial lipid chemistry, our project has the potential to

substantially advance genomic editor delivery to the pulmonary system. These innovations could reconfigure therapeutic strategies for CF and other genetic diseases caused by nonsense mutations. The feasibility of this high-impact work is reinforced by our lab's established expertise in these technologies, making it a viable

candidate for significantly advancing the nonviral delivery of genomic medicines and thereby enhancing the therapeutic options for a wide array of lung diseases.