Targeting Recycling Endosomes to Potentiate mRNA Lipid Nanoparticles

Area of Science:

• Biotechnology
• Molecular Biology
• Drug Delivery

Background:

• Messenger RNA (mRNA) lipid nanoparticles (LNPs) are promising for treating cancer, infectious, and immune diseases.
• Endosomal entrapment of delivered mRNA limits the therapeutic efficacy of mRNA-LNPs.
• The precise molecular mechanisms of LNP-mediated mRNA delivery remain incompletely understood.

Purpose of the Study:

• To investigate the molecular mechanisms of mRNA-LNP delivery.
• To identify strategies for enhancing mRNA expression from LNPs.
• To overcome the challenge of endosomal entrapment in mRNA-LNP therapeutics.

Main Methods:

• Utilized a library of small molecules targeting endosomal trafficking pathways.
• Assessed mRNA delivery and expression in cellular and in vivo (live mice) models.
• Characterized the interaction of small molecules with endosomal components, specifically Annexin A6.

Main Results:

• Inhibition of endocytic recycling significantly enhanced mRNA expression from LNPs.
• Endosidine 5 (ES5), a potent small molecule, was identified as an enhancer of mRNA delivery.
• ES5 was shown to disrupt recycling endosomes via Annexin A6, facilitating cytoplasmic mRNA release and expression.

Conclusions:

• Targeting endosomal trafficking with small molecules is a viable strategy to improve mRNA-LNP efficacy.
• ES5 demonstrates potential as an adjuvant to enhance mRNA-LNP-based therapies.
• Understanding and manipulating endosomal escape mechanisms can optimize mRNA delivery systems.