Expression Kinetics and Innate Immune Response after Electroporation and LNP-Mediated Delivery of a Self-Amplifying mRNA in the Skin

Hanne Huysmans; Zifu Zhong; Joyca De Temmerman; Barbara L Mui; Ying K Tam; Séan Mc Cafferty; Arlieke Gitsels; Daisy Vanrompay; Niek N Sanders

doi:10.1016/j.omtn.2019.08.001

Expression Kinetics and Innate Immune Response after Electroporation and LNP-Mediated Delivery of a Self-Amplifying mRNA in the Skin

Mol Ther Nucleic Acids. 2019 Sep 6:17:867-878. doi: 10.1016/j.omtn.2019.08.001. Epub 2019 Aug 7.

Authors

Hanne Huysmans¹, Zifu Zhong¹, Joyca De Temmerman², Barbara L Mui³, Ying K Tam³, Séan Mc Cafferty⁴, Arlieke Gitsels⁵, Daisy Vanrompay⁶, Niek N Sanders⁷

Affiliations

¹ Laboratory of Gene Therapy, Department of Nutrition, Genetics and Ethology, Faculty of Veterinary Medicine, Ghent University, 9820 Merelbeke, Belgium.
² Laboratory of Gene Therapy, Department of Nutrition, Genetics and Ethology, Faculty of Veterinary Medicine, Ghent University, 9820 Merelbeke, Belgium; Department of Pathology, Bacteriology and Poultry Diseases, Faculty of Veterinary Medicine, Ghent University, 9820 Merelbeke, Belgium.
³ Acuitas Therapeutics, Vancouver, BC V6T 1Z3, Canada.
⁴ Laboratory of Gene Therapy, Department of Nutrition, Genetics and Ethology, Faculty of Veterinary Medicine, Ghent University, 9820 Merelbeke, Belgium; Cancer Research Institute (CRIG), Ghent University, Ghent, Belgium.
⁵ Laboratory of Gene Therapy, Department of Nutrition, Genetics and Ethology, Faculty of Veterinary Medicine, Ghent University, 9820 Merelbeke, Belgium; Laboratory for Immunology and Animal Biotechnology, Department of Animal Production, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium.
⁶ Laboratory for Immunology and Animal Biotechnology, Department of Animal Production, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium.
⁷ Laboratory of Gene Therapy, Department of Nutrition, Genetics and Ethology, Faculty of Veterinary Medicine, Ghent University, 9820 Merelbeke, Belgium; Cancer Research Institute (CRIG), Ghent University, Ghent, Belgium. Electronic address: [email protected].

Abstract

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.

Keywords: electroporation; expression kinetics; innate immune response; intradermal; lipid nanoparticles; mice; non-replicating mRNA; pDNA; self-amplifying mRNA.