l-Type amino acid transporter 1-targeting nanoparticles for antisense oligonucleotide delivery to the CNS

Mol Ther Nucleic Acids. 2024 Sep 16;35(4):102340. doi: 10.1016/j.omtn.2024.102340. eCollection 2024 Dec 10.

Abstract

l-Type amino acid transporter 1 (LAT1)-specific ligands and polyion complexes are used as brain-specific targets to deliver RNA-based drugs across the blood-brain barrier. We characterized an LAT1-targeting antisense oligonucleotide (ASO)-encapsulated nanoparticle, Phe-NPs/ASO. A 25% density of phenylalanine effectively binds to the surface of LAT1-targeting NPs in the GL261-Luc cells, and Phe-NPs/ASO shows higher binding affinity compared to that without phenylalanine by cellular binding assay. To further characterize the blood-brain barrier-targeting effect and tissue distribution following a single-dose intravenous injection in mice, we performed in vivo biodistribution studies using fluorescence imaging. The Phe-NPs/ASOs were detected in the brain tissue 1 h post-intravenous injection at an approximately 64-fold higher ratio than that of the same ASOs administered in the absence of any NP carrier. The brain tissue delivery of ASO-loaded Phe-NPs was also confirmed in a fluorescence imaging study performed in non-human primates. These results demonstrate that Phe-NPs may successfully deliver an ASO to the brain tissue across brain regions. Phe-NPs loaded with RNA-based drugs have the potential to treat diseases of the CNS, including all forms of neurodegenerative diseases.

Keywords: ASO; ASO delivery; BBB; LAT1; LAT1-targeting nanoparticles; MT: Oligonucleotides: Therapies and Applications; NPs; PEG-PLL; antisense oligonucleotide; blood-brain barrier; l-type amino acid transporter 1; polyion complex micelle.