Isosteric 3D Bicyclo[1.1.1]Pentane (BCP) Core-Based Lipids for mRNA Delivery and CRISPR/Cas Gene Editing

Area of Science:

• Biochemistry
• Materials Science
• Pharmaceutical Sciences

Background:

• Lipid nanoparticles (LNPs) are critical for mRNA vaccines and gene editing therapies.
• Current ionizable amino lipids are limited to 2D structures, potentially hindering delivery efficiency.
• Three-dimensional (3D) drug architectures can improve physicochemical properties.

Purpose of the Study:

• To design and synthesize novel 3D ionizable amino lipids using bicyclo[1.1.1]pentane (BCP) core motifs.
• To evaluate the in vivo performance of BCP-based LNPs for mRNA delivery and gene editing.
• To compare the efficacy of 3D BCP-based lipids against 2D analogues and a clinically used LNP.

Main Methods:

• Synthesis of 3D ionizable lipids incorporating BCP core structures.
• Formulation of LNPs using BCP-based lipids.
• In vivo evaluation of LNP-mediated mRNA delivery to the liver and spleen.
• Assessment of gene editing efficiency using CRISPR/Cas9 targeting PCSK9.

Main Results:

• BCP-based lipids demonstrated efficient in vivo mRNA delivery to the liver and spleen.
• 3D BCP-based LNPs significantly outperformed 2D benzene- and cyclohexane-based analogues.
• Lead BCP-NC2-C12 LNPs achieved ~90% PCSK9 reduction via CRISPR/Cas9 gene knockout, surpassing 2D controls and DLin-MC3-DMA LNPs.
• The study introduces superior 3D ionizable lipid designs with enhanced in vivo activity.

Conclusions:

• The introduction of 3D BCP core motifs expands the chemical diversity of ionizable amino lipids.
• BCP-based LNPs represent a promising advancement for improving mRNA and gene editing delivery efficiency.
• This work offers a new avenue for the development of next-generation genetic medicines.