Mitochondria-targeted gene delivery using fluorinated lipid nanoparticles to alleviate Leber's hereditary optic neuropathy.

Mutations in mitochondrial DNA (mtDNA) lead to various mitochondrial diseases for which no cure is currently available. Despite the promising potential of mtDNA correction to treat these disorders, the double mitochondrial membranes have proven to be a tough barrier to overcome. Here, we develop fluorinated lipid nanoparticles with a mitochondrial targeting sequence (F-M-LNP) to overcome the mitochondrial barrier by virtue of their high affinity for mitochondrial membranes, thereby effectively introducing gene into mitochondria. Through the rational design of ionizable lipid structures, we synthesize 16 lipid nanoparticles (LNPs) with varying degrees of fluorination and investigate the key structural features required for efficient mitochondria-targeted gene delivery. As fluorinated ionizable lipid-mediated mitochondrial transport is independent of mitochondrial membrane potential (MMP), F-M-LNPs deliver gene to mitochondria under pathological conditions where MMP is impaired, resulting in a 3.8-fold increase in functional protein expression compared to non-fluorinated LNPs. In a male mouse model of genetically induced mitochondrial disease, F-M-LNP demonstrate functional complementation of mutant mtDNA, alleviating disease symptoms. Together, our results show that modifying vectors with fluorinated groups offers valuable tools for correcting mitochondrial genome defects.