BPS2026 – Protein corona formed on lipid nanoparticles compromises delivery efficiency of mRNA cargo

Effective delivery carriers for RNA are critical for the development of next-generation RNA-based therapeutics, and lipid nanoparticles (LNPs) are among the most advanced RNA delivery systems available. However, the potency of LNPs is hindered by inefficient endosomal escape and poor tissue specificity. It is essential to understand how LNPs behave in biological environments to address these challenges. Proteins in human plasma spontaneously bind to LNPs as soon as LNPs are introduced into the body, forming an unavoidable protein coating called the protein corona. Proteins play important roles in cellular and endosomal membrane functions, which can impact how LNPs interact with biological membranes. However, it is challenging to isolate the protein corona from soft nanoparticles like LNPs. Herein, we developed a workflow using gradient centrifugation to isolate LNPs from biofluids and identify proteins with mass spectrometry. This method allows us to analyze protein corona components quantitatively, label-free with minimal influence of endogenous biological particles. Utilizing this platform, we discovered that vitronectin, C-reactive protein, and alpha-2-macroglobulin are consistently enriched on LNP surfaces. Among these corona proteins, vitronectin enhances LNP uptake by up to 330% but—surprisingly—decrease mRNA expression by over 50% while lysosome colocalization is similar to control LNPs. These results indicate there is a discrepancy between LNP cellular internalization and the fate of mRNA payloads following cell entry, through mechanisms that are not well understood. In summary, our work introduces a reliable method that can analyze the protein corona components of LNPs, and these proteins influence not only LNP uptake but lysosomal trafficking as well. These results highlight the importance of understanding the role of protein corona in nanoparticle mediated drug delivery.