Improving endosomal escape of lipid nanoparticles

People involved

M.Sc. Zhuqing Dai (PhD student funded by the PRC) - University of Groningen, The Netherlands

Abstract

Lipid nanoparticles (LNPs) have recently seen immense success for the delivery of messenger RNA (mRNA), both for therapy and vaccination. This success notwithstanding, there are several challenges holding back an even wider usage. While LNPs can readily escort the mRNA into cells, the clear majority of particles remains trapped in the endo/lysosomal compartments of the cell and the mRNA is thereby not delivered to the cytosol to exert its function.

This project aims to improve the efficiency of escape from the endosomes by a quantitative study of how LNPs enter, distribute within, and exit cells. We will create a library of LNPs with different properties using automatic microfluidic preparation. We will subsequently screen the LNPs for their cell uptake, endosomal escape and mRNA expression. Based on these observations, we will identify strategies on how to improve the efficiency of endosomal escape. We will test these strategies in more detailed studies where each step of the process is studied: cell internalization, endolysosomal processing, endosomal escape and potential cell export.

Ultimately, our strategies to achieve more efficient endosomal escape will support better mRNA delivery in future.

Benefit for the community

Escape from the endosomes is the perhaps most important bottleneck towards achieving efficient delivery of nucleic acids (siRNA, mRNA or DNA) or, indeed, macromolecules in general.4)5)6)7)

For lipid nanoparticles (LNPs) specifically it has been reported that only a few percent of internalized particles manages to release their cargo.1)2) Any improvement on this state of affairs is consequently going to have a large impact; for example, by increasing the endosomal escape of LNPs from 1 to 5%, a 5 times lower dose can be used, thereby reducing the occurrence of side effects, not to mention that 5 times more patients can be treated with the same production capacity. In times of a pandemic outbreak, this would make a huge difference. The outcome of this project will be a set of strategies for how best to achieve endosomal escape.

Overall, our intention is that anyone working on LNP-based delivery (and potentially drug delivery in general) can use our strategies and observations to improve the performance of their respective drug delivery platform in future.8)9)

Visit the supervisors lab

Dr. Christoffer Åberg and Prof. Dr. Enrico Mastrobattista