Self-replicating RNA vaccine functionality modulated by fine-tuning of polyplex delivery vehicle structure.

Autor: Démoulins T; Institute of Virology and Immunology (IVI), Sensemattstrasse 293, CH-3147 Mittelhäusern, Switzerland. Electronic address: thomas.demoulins@ivi.admin.ch., Ebensen T; Helmholtz Centre for Infection Research Braunschweig (HZI), Department of Vaccinology and Applied Microbiology, Braunschweig, Germany., Schulze K; Helmholtz Centre for Infection Research Braunschweig (HZI), Department of Vaccinology and Applied Microbiology, Braunschweig, Germany., Englezou PC; Institute of Virology and Immunology (IVI), Sensemattstrasse 293, CH-3147 Mittelhäusern, Switzerland., Pelliccia M; NorthWest Centre of Advanced Drug Delivery (NoWCADD), Division of Pharmacy and Optometry, School of Health Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester M13 9PT, UK., Guzmán CA; Helmholtz Centre for Infection Research Braunschweig (HZI), Department of Vaccinology and Applied Microbiology, Braunschweig, Germany., Ruggli N; Institute of Virology and Immunology (IVI), Sensemattstrasse 293, CH-3147 Mittelhäusern, Switzerland., McCullough KC; Institute of Virology and Immunology (IVI), Sensemattstrasse 293, CH-3147 Mittelhäusern, Switzerland.
Jazyk: angličtina
Zdroj: Journal of controlled release : official journal of the Controlled Release Society [J Control Release] 2017 Nov 28; Vol. 266, pp. 256-271. Date of Electronic Publication: 2017 Sep 19.
DOI: 10.1016/j.jconrel.2017.09.018
Abstrakt: The major limitations with large and complex self-amplifying RNA vaccines (RepRNA) are RNase-sensitivity and inefficient translation in dendritic cells (DCs). Condensing RepRNA with polyethylenimine (PEI) gave positive in vitro readouts, but was largely inferior to virus-like replicon particles (VRP) or direct electroporation. In the present study, we improved such polyplex formulation and determined that fine-tuning of the polyplex structure is essential for ensuring efficacious translation. Thereby, three parameters dominate: (i) PEI molecular weight (MW); (ii) RepRNA:PEI (weight:weight) ratio; and (iii) inclusion of cell penetrating peptides (CPPs). Seven commercially available linear PEIs (MW 2,500-250,000) were classified as strong, intermediate or low for their aptitude at complexing and protecting RepRNA for delivery into porcine blood DCs. Inclusion of (Arg) 9 or TAT(57-57) CPPs further modified the translation readouts, but varied for different gene expressions. Dependent on the formulation, translation of the gene of interest (GOI) inserted into the RepRNA (luciferase, or influenza virus hemagglutinin or nucleoprotein) could decrease, while the RepRNA structural gene (E2) translation increased. This was noted in the porcine SK6 cell line, as well as both porcine and, for the first time, human DCs. Two formulations - [Rep/PEI-4,000 (1:3)] and [Rep/PEI-40,000 (1:2)/(Arg) 9 ] were efficacious in vivo in mice and pigs, where specific CD8 + T and CD4 + T-cell responses against the GOI-encoded antigen were observed for the first time. The results demonstrate that different polyplex formulations differ in their interaction with the RepRNA such that only certain genes can be translated. Thus, delivery of these large self-replicating RNA molecules require definition with respect to translation of different genes, rather than just the GOI as is the norm, for identifying optimal delivery for the desired immune activation in vivo.
(Copyright © 2017 Elsevier B.V. All rights reserved.)
Databáze: MEDLINE
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