In vitro and in vivo mRNA delivery using lipid-enveloped pHresponsive polymer nanoparticles

Biodegradable core−shell structured nanoparticles with a poly(β-amino ester) (PBAE) core enveloped by a phospholipid bilayer shell were developed for in vivo mRNA delivery with a view toward delivery of mRNA-based vaccines. The pH-responsive PBAE component was chosen to promote endosome disruption, while the lipid surface layer was selected to minimize toxicity of the polycation core. Messenger RNA was efficiently adsorbed via electrostatic interactions onto the surface of these net positively charged nanoparticles. In vitro, mRNA-loaded particle uptake by dendritic cells led to mRNA delivery into the cytosol with low cytotoxicity, followed by translation of the encoded protein in these difficult-to-transfect cells at a frequency of 30%. Particles loaded with mRNA administered intranasally (i.n.) in mice led to the expression of the reporter protein luciferase in vivo as soon as 6 h after administration, a time point when naked mRNA given i.n. showed no expression. At later time points, luciferase expression was detected in naked mRNA-treated mice, but this group showed a wide variation in levels of transfection, compared to particle-treated mice. This system may thus be promising for noninvasive delivery of mRNA-based vaccines.United States. Dept. of Defense (Institute for Soldier Nanotechnology, contract W911NF-07-D-0004)Ragon Institute of MGH, MIT and HarvardSingapore. Agency for Science, Technology and ResearchHoward Hughes Medical Institute (Investigator

Phase Behavior of Ascorbyl Palmitate Coagels Loaded with Oligonucleotides as a New Carrier for Vaccine Adjuvants

In this work, the phase behavior variations of an ascorbyl palmitate (Asc16) system in aqueous solution were analyzed when immunologically active hydrophilic compounds (CpG and OVA) were introduced. This study was carried out through optical polarizing microscopy (OPM) and differential scanning calorimetry (DSC) at different temperatures and over a broad range of concentrations. The combination of both techniques allowed the determination of a complete phase diagram which was compared with those built for Asc16-water system and it was demonstrated that fixed concentrations of hydrophilic compounds (300 and 24 µg/g for CpG-ODN and OVA respectively) generate two lamellar liquid crystals, a cubic liquid crystal phase, and also other aggregates. However, no changes were observed in the phase diagram in terms of formation of new mesophases. The aqueous phase behavior was also studied as a function of surfactant and temperature. DSC and Fourier transform infrared spectroscopy (FT-IR) measurements show differences in the free water and mainly in the secondary hydration layer, which confirm that the studied compounds are situated in the aqueous domain. The construction and analysis of Asc16 phase diagrams with a fixed concentration of CpG-ODN/OVA allows the comprehension of Asc16 phase behavior and could be easily adapted to other concentrations. Moreover, these findings could be extrapolated to other hydrophilic substances in aqueous solution introduced in liquid crystal phases since they follow a similar behavior as those reported in the literature.Fil: Ullio Gamboa, Gabriela Veronica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Unidad de Investigación y Desarrollo en Tecnología Farmacéutica. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Unidad de Investigación y Desarrollo en Tecnología Farmacéutica; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Farmacia; ArgentinaFil: Benedini, Luciano Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; ArgentinaFil: Schulz, Pablo Carlos. Universidad Nacional del Sur. Departamento de Química; ArgentinaFil: Allemandi, Daniel Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Unidad de Investigación y Desarrollo en Tecnología Farmacéutica. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Unidad de Investigación y Desarrollo en Tecnología Farmacéutica; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Farmacia; Argentin