학술논문
Non-replicative antibiotic resistance-free DNA vaccine encoding S and N proteins induces full protection in mice against SARS-CoV-2
Document Type
article
Author
Pedro J. Alcolea; Jaime Larraga; Daniel Rodríguez-Martín; Ana Alonso; Francisco J. Loayza; José M. Rojas; Silvia Ruiz-García; Andrés Louloudes-Lázaro; Ana B. Carlón; Pedro J. Sánchez-Cordón; Pablo Nogales-Altozano; Natalia Redondo; Miguel Manzano; Daniel Lozano; Jesús Palomero; María Montoya; María Vallet-Regí; Verónica Martín; Noemí Sevilla; Vicente Larraga
Source
Frontiers in Immunology, Vol 13 (2022)
Subject
Language
English
ISSN
1664-3224
Abstract
SARS-CoV-2 vaccines currently in use have contributed to controlling the COVID-19 pandemic. Notwithstanding, the high mutation rate, fundamentally in the spike glycoprotein (S), is causing the emergence of new variants. Solely utilizing this antigen is a drawback that may reduce the efficacy of these vaccines. Herein we present a DNA vaccine candidate that contains the genes encoding the S and the nucleocapsid (N) proteins implemented into the non-replicative mammalian expression plasmid vector, pPAL. This plasmid lacks antibiotic resistance genes and contains an alternative selectable marker for production. The S gene sequence was modified to avoid furin cleavage (Sfs). Potent humoral and cellular immune responses were observed in C57BL/6J mice vaccinated with pPAL-Sfs + pPAL-N following a prime/boost regimen by the intramuscular route applying in vivo electroporation. The immunogen fully protected K18-hACE2 mice against a lethal dose (105 PFU) of SARS-CoV-2. Viral replication was completely controlled in the lungs, brain, and heart of vaccinated mice. Therefore, pPAL-Sfs + pPAL-N is a promising DNA vaccine candidate for protection from COVID-19.