Engineering asymmetric nanoscale lipid vesicles for drug delivery

The delivery of therapeutics to cells enables both the treatment and the prevention of diseases. To protect therapeutics from degradation and enable cell-specific targeting, they are often encapsulated into drug delivery vehicles such as lipid nanoparticles, viral vectors or lipid vesicles. These delivery vehicles have been extremely successful in delivering small molecules, nucleic acids or proteins. However, there is no universal drug delivery vehicle that can deliver therapeutics irrespective of the choice of cargo. Here, we present a method to engineer lipid vesicles with asymmetric leaflets and show that they can deliver mRNA and proteins to cells. We also find that the leaflet asymmetry can increase the lipid vesicle uptake by cells. When we load asymmetric vesicles with mRNA, we observe a 5-fold increase in the transfection efficiency indicative of an improved uptake and release by asymmetric vesicles. Moreover, our findings extend beyond mRNA cargos by showcasing the effectiveness of asymmetric vesicles in delivering a wide range of proteins to cells, including the promising CRISPR/Cas9 gene editing system. Our method and findings expand the parameter space for engineering drug delivery vehicles and demonstrate the pivotal role of leaflet asymmetry in determining the performance of drug delivery vehicles. Consequently, our work leads to many applications, including the formation of more efficient universal drug carriers and the delivery of gene-editing proteins to cells.