Abstract
The coronavirus disease 2019 (COVID-19) pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has become a public health emergency of international concern, and an effective vaccine is urgently needed to control the pandemic. Envelope (E) and membrane (M) proteins are highly conserved structural proteins among SARS-CoV-2 and SARS-CoV and have been proposed as potential targets for the development of cross-protective vaccines. Here, synthetic DNA vaccines encoding SARS-CoV-2 E/M proteins (called p-SARS-CoV-2-E/M) were developed, and mice were immunised with three doses via intramuscular injection and electroporation. Significant cellular immune responses were elicited, whereas no robust humoral immunity was detected. In addition, novel H-2d-restricted T-cell epitopes were identified. Notably, although no drop in lung tissue virus titre was detected in DNA-vaccinated mice post-challenge with SARS-CoV-2, immunisation with either p-SARS-CoV-2-E or p-SARS-CoV-2-M provided minor protection and co-immunisation with p-SARS-CoV-2-E+M increased protection. Therefore, E/M proteins should be considered as vaccine candidates as they may be valuable in the optimisation of vaccination strategies against COVID-19.
Keywords: DNA vaccine; SARS-CoV-2; cellular response; envelope protein; humoral response; membrane protein.
【저자키워드】 SARS-CoV-2, Humoral response, membrane protein, envelope protein, DNA vaccine, cellular response, 【초록키워드】 COVID-19, coronavirus disease, Coronavirus disease 2019, Vaccine, coronavirus, pandemic, Vaccines, SARS-CoV, Cellular immune response, severe acute respiratory syndrome Coronavirus, virus, Protein, DNA, Epitopes, Humoral immunity, Humoral response, mice, membrane protein, immune responses, International, Vaccination strategies, immunisation, vaccine candidate, envelope, membrane, structural proteins, envelope protein, target, structural protein, public health emergency, respiratory, DNA vaccine, T-cell epitope, cellular response, cellular, dose, Electroporation, Vaccination strategy, humoral, Intramuscular injection, acute respiratory syndrome, acute respiratory syndrome coronavirus, acute respiratory syndrome coronavirus 2, lung tissue, titre, vaccine candidates, effective, robust, caused, conserved, addition, provided, cross-protective, elicited, Significant, 【제목키워드】 protection, DNA, Partial, Against,