Fusion-dependent formation of lipid nanoparticles containing macromolecular payloads
Creators
- 1. University of British Columbia
- 2. University Children's Hospital Zurich and Children's Reserach Center
Description
The success of Onpattro™ (patisiran) clearly demonstrates the utility of lipid nanoparticle (LNP) systems
for enabling gene therapies. These systems are composed of ionizable cationic lipids, phospholipid,
cholesterol, and polyethylene glycol (PEG)-lipids, and are produced through rapid-mixing of an ethanolic-
lipid solution with an acidic aqueous solution followed by dialysis into neutralizing buffer. A detailed
understanding of the mechanism of LNP formation is crucial to improving LNP design. Here we use cryogenic
transmission electron microscopy and fluorescence techniques to further demonstrate that LNP are
formed through the fusion of precursor, pH-sensitive liposomes into large electron-dense core structures
as the pH is neutralized. Next, we show that the fusion process is limited by the accumulation of PEGlipid
on the emerging particle. Finally, we show that the fusion-dependent mechanism of formation
also applies to LNP containing macromolecular payloads including mRNA, DNA vectors, and gold
nanoparticles.
Files
MC.eGFP1 gel analysis.zip
Additional details
Funding
- Swiss National Science Foundation
- Development of novel synthetic gene transfer vectors for metabolic liver therapy CRSII5_180257