Among the vaccines have been developed thus far against SARS-CoV-2, the mRNA-based ones have demonstrated more promising results regarding both safety and efficacy. Two remarkable features of the mRNA vaccines introduced by the Pfizer/BioNTech and Moderna companies are the use of (N 1 -methyl-pseudouridine-) modified mRNA and the microfluidics-based production of lipid nanoparticles (LNPs) as the carrier. In the present study, except Anti-Reverse Cap Analog (ARCA), no other nucleoside analogs were employed to synthesize Spike-encoding mRNA using the in vitro transcription (IVT) method. Furthermore, LNPs were prepared via the ethanol injection method commonly used for liposome formation as an alternative for microfluidics-based approaches. The produced mRNA-LNP vaccine was evaluated for nanoparticles characteristics, encapsulation and transfection efficiencies, in vitro cytotoxicity as well as stability and storability. The safety of vaccine was assessed in Balb/c mice injected with mRNA-LNPs containing 10 µg of spike-encoding mRNA. Eventually, the vaccine efficacy in inducing an immune response against SARS-CoV-2 was studied in Balb/c and C57BL/6 mice (received either 1 or 10 µg of mRNA) as well as in rhesus macaque monkeys (infused with mRNA-LNPs containing 100 µg of mRNA). The ELISA and virus neutralizing test (VNT) results showed a significant augmentation in the level of neutralizing antibodies against SARS-CoV-2. Moreover, the ELISA assay showed virus-specific IFN-γ secretion in immunized mice as a marker of T H 1 cell-based immune response, whereas favorably no change in the production of IL-4 was detected.
【저자키워드】 SARS-CoV-2, LNP, Spike protein, Lipid nanoparticle, mRNA-vaccine, 【초록키워드】 neutralizing antibody, Efficacy, Vaccine, immune response, mRNA vaccine, cytotoxicity, in vitro, virus, ELISA, stability, Characteristics, mice, mRNA, nucleoside analog, Neutralizing, encapsulation, ELISA assay, Moderna, IFN-γ, Pfizer/BioNTech, marker, IL-4, Liposome, approaches, secretion, injection, rhesus, immunized mice, C57BL/6, CAP, VNT, feature, produced, evaluated, injected, introduced, demonstrated, the vaccine, in vitro transcription, infused, mRNA-based, 【제목키워드】 response, macaque, mouse, development,