LNP vaccine formulation screening for cellular uptake using BODIPY-labeled lipid nanoparticles

BEBPA EUR Bioassay 2023 -- RNA vaccines, comprising a mRNA encapsulated in a lipid nanoparticle (LNP), are a new modality for rapid development of synthetic prophylactic and therapeutic vaccines. The LNP acts as a device to deliver the RNA payload into the cell cytoplasm for translation of the transgene; moreover, the precise formulation of cationic/ionisable lipid, phospholipid, PEGylated lipid and cholesterol can affect the LNP cellular interaction. Crucial to the mRNA delivery is cellular uptake and escape from the endosomal compartment. To evaluate the effects of formulation components on cell uptake, a cell-based assay using the fluorescent dye 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY)-labelled LNPs has been developed. Using a microfluidic production process, BODIPY-cholesterol has been incorporated into a range of lipid nanoparticle formulations as a potential screen for evaluating LNP formulations.