Nanoparticle stereochemistry-dependent endocytic processing improves in vivo mRNA delivery

Stereochemistry can alter small-molecule pharmacokinetics, safety and efficacy. However, it is unclear whether the stereochemistry of a single compound within a multicomponent colloid such as a lipid nanoparticle (LNP) can influence its activity in vivo. Here we report that LNPs containing stereopure 20 alpha-hydroxycholesterol (20 alpha) delivered mRNA to liver cells up to 3-fold more potently than LNPs containing a mixture of both 20 alpha- and 20 beta-hydroxycholesterols (20mix). This effect was not driven by LNP physiochemical traits. Instead, in vivo single-cell RNA sequencing and imaging revealed that 20mix LNPs were sorted into phagocytic pathways more than 20 alpha LNPs, resulting in key differences between LNP biodistribution and subsequent LNP functional delivery. These data are consistent with the fact that nanoparticle biodistribution is necessary, but not sufficient, for mRNA delivery, and that stereochemistry-dependent interactions between LNPs and target cells can improve mRNA delivery.

Automated summary

Stereochemistry affects the pharmacokinetics, safety, and efficacy of small molecules. It is unclear whether the stereochemistry of a single compound within a multicomponent colloid can influence its activity in vivo.