Examining Intracellular Trafficking of Nucleic Acid Containing Lipid Nanoparticles for Non-Viral Gene Delivery

Lipid Nano Particle (LNP) technology is currently one of the most promising and emerging technologies for delivery of nucleic acid therapeutics. The recent approvals of COVID-19 vaccines have demonstrated the feasibility, manufacturability and clinical safety of lipid based nano carriers. The choice of each lipid component (namely, Ionizable lipid. Helper lipid, Cholesterol and Pegylated lipid) that comprises a LNP is critical in determining the in-vivo behavior and efficacy of nucleic acid delivery. In addition, these parameters can be modulated to maneuver and change the biodistribution of LNPs depending on the organ of interest. Further specificity especially for organs that lack endogenous targeting, cellular uptake can be further improved by use of targeting ligands. Hence selecting the right LNP composition based upon the target of interest and gene to be delivered becomes extremely critical. With all the challenges associated it is important to understand the intracellular behavior of LNPs. Here an equimolar mixture of fluorescently labeled nucleic acid and a GFP producing nucleic acid was encapsulated inside the LNP that was manufactured using a microfluidic platform to examine cellular uptake, endosomal release, and intracellular trafficking. This technique and platform allow for comparison of intracellular trafficking and nuclear uptake with different LNP formulations and ionizable lipids employed, enabling improved screening prior to in vivo studies.