Lipid-mRNA Nanoparticle Designedto Enhance Intracellular Delivery Mediated by Shock Waves

摘要

Cellular membranes are, in general, impermeable to macromolecules (herein referred to as macrodrugs, e.g., recombinant protein, expression plasmids, or mRNA), which is a major barrier for clinical translation of macrodrug-based therapies. Encapsulation of macromolecules in lipid nanoparticles (LNPs) can protect the therapeutic agent during transport through the body and facilitate the intracellular delivery via a fusion-based pathway. Furthermore, designing LNPs responsive to stimuli can make their delivery more localized, thus limiting the side effects. However, the principles and criteria for designing such nanoparticles remain unclear. We show that the thermodynamic state of the lipid membrane of the nanoparticle is a key design principle for acoustically responsive fusogenic nanoparticles. We have optimized a cationic LNP (designated LNPLH) with two different phase transitions near physiological conditions for delivering mRNA. A bicistronic mRNA encoding a single domain intracellular antibody fragment and green fluorescent protein (GFP) was introduced into a range of human cancer cell types usingLNPLH, and the protein expression was measured via fluorescencecorresponding to the GFP expression. The LNPLH/mRNA complexdemonstrated low toxicity and high delivery, which was significantlyenhanced when the transfection occurred in the presence of acousticshock waves. The results suggest that the thermodynamic state of LNPsprovides an important criterion for stimulus responsive fusogenicnanoparticles to deliver macrodrugs to the inside of cells.