In this work, we studied the expression kinetics and innate immune response of a self-amplifying mRNA (sa-RNA) after electroporation and lipid-nanoparticle (LNP)-mediated delivery in the skin of mice. Intradermal electroporation of the sa-RNA resulted in a plateau-shaped expression, with the plateau between day 3 and day 10. The overall protein expression of sa-RNA was significantly higher than that obtained after electroporation of plasmid DNA (pDNA) or non-replication mRNAs. Moreover, using IFN-β reporter mice, we elucidated that intradermal electroporation of sa-RNA induced a short-lived moderate innate immune response, which did not affect the expression of the sa-RNA. A completely different expression profile and innate immune response were observed when LNPs were used. The expression peaked 24 h after intradermal injection of sa-RNA-LNPs and subsequently showed a sharp drop. This drop might be explained by a translational blockage caused by the strong innate immune response that we observed in IFN-β reporter mice shortly (4 h) after intradermal injection of sa-RNA-LNPs. A final interesting observation was the capacity of sa-RNA-LNPs to transfect the draining lymph nodes after intradermal injection.

中文翻译：

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电穿孔和 LNP 介导的皮肤中自我扩增 mRNA 递送后的表达动力学和先天免疫反应


在这项工作中，我们研究了自放大 mRNA (sa-RNA) 在电穿孔和脂质纳米颗粒 (LNP) 介导的小鼠皮肤递送后的表达动力学和先天免疫反应。 sa-RNA 的皮内电穿孔导致平台型表达，平台期在第 3 天到第 10 天之间。sa-RNA 的总体蛋白表达显着高于质粒 DNA (pDNA) 或非电穿孔后获得的蛋白表达。复制 mRNA。此外，使用IFN-β报告小鼠，我们阐明了sa-RNA的皮内电穿孔诱导了短暂的中等先天免疫反应，这并不影响sa-RNA的表达。当使用 LNP 时，观察到完全不同的表达谱和先天免疫反应。皮内注射 sa-RNA-LNP 24 小时后表达达到峰值，随后急剧下降。这种下降可能是由于我们在皮内注射 sa-RNA-LNP 后不久（4 小时）在 IFN-β 报告小鼠中观察到的强烈先天免疫反应引起的翻译阻断所致。最后一个有趣的观察结果是 sa-RNA-LNP 在皮内注射后转染引流淋巴结的能力。