Chander Nisha, Basha Genc, Yan Cheng Miffy Hok, Witzigmann Dominik, Cullis Pieter R
Department of Biochemistry and Molecular Biology, University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC V6T 1Z3, Canada.
NanoVation Therapeutics, 2405 Wesbrook Mall, Vancouver, BC V6T 1Z3, Canada.
Mol Ther Methods Clin Dev. 2023 Jun 12;30:235-245. doi: 10.1016/j.omtm.2023.06.005. eCollection 2023 Sep 14.
Lipid nanoparticles (LNPs) for delivery of mRNA usually contain ionizable lipid/helper lipid/cholesterol/PEG-lipid in molar ratios of 50:10:38.5:1.5, respectively. These LNPs are rapidly cleared from the circulation following intravenous (i.v.) administration, limiting uptake into other tissues. Here, we investigate the properties of LNP mRNA systems prepared with high levels of "helper" lipids such as 1,2-distearoyl-sn-glycero-3-phosphorylcholine (DSPC) or N-(hexadecanoyl)-sphing-4-enine-1-phosphocholine (egg sphingomyelin [ESM]). We show that LNP mRNAs containing 40 mol % DSPC or ESM have a unique morphology with a small interior "solid" core situated in an aqueous compartment that is bounded by a lipid bilayer. The encapsulated mRNA exhibits enhanced stability in the presence of serum. LNP mRNA systems containing 40 mol % DSPC or ESM exhibit significantly improved transfection properties compared with systems containing 10 mol % DSPC or ESM. When injected i.v., LNP mRNAs containing 40 mol % ESM exhibit extended circulation lifetimes compared with LNP mRNA systems containing 10 mol % DSPC, resulting in improved accumulation in extrahepatic tissues. Systems containing 40 mol % ESM result in significantly improved gene expression in spleen and bone marrow as well as liver post i.v. injection compared with 10 mol % DSPC LNP mRNAs. We conclude that LNP mRNAs containing high levels of helper lipid provide a new approach for transfecting hepatic and extrahepatic tissues.
用于递送信使核糖核酸（mRNA）的脂质纳米颗粒（LNP）通常分别含有摩尔比为50:10:38.5:1.5的可电离脂质/辅助脂质/胆固醇/聚乙二醇脂质。这些LNP在静脉内（i.v.）给药后会迅速从循环系统中清除，限制了对其他组织的摄取。在此，我们研究了用高水平“辅助”脂质（如1,2-二硬脂酰-sn-甘油-3-磷酸胆碱（DSPC）或N-（十六烷酰）-鞘氨醇-4-烯-1-磷酸胆碱（卵鞘磷脂[ESM]））制备的LNP mRNA系统的特性。我们发现，含有40摩尔%DSPC或ESM的LNP mRNA具有独特的形态，其内部有一个小的“固体”核心，位于由脂质双层包围的水相隔室中。包封的mRNA在血清存在下表现出增强的稳定性。与含有10摩尔%DSPC或ESM的系统相比，含有40摩尔%DSPC或ESM的LNP mRNA系统表现出显著改善的转染特性。静脉注射时，与含有10摩尔%DSPC的LNP mRNA系统相比，含有40摩尔%ESM的LNP mRNA具有更长的循环寿命，从而改善了在肝外组织中的积累。与10摩尔%DSPC的LNP mRNA相比，含有40摩尔%ESM的系统在静脉注射后在脾脏、骨髓以及肝脏中导致显著改善的基因表达。我们得出结论，含有高水平辅助脂质的LNP mRNA为转染肝组织和肝外组织提供了一种新方法。
