Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged in December 20191,2 and is responsible for the coronavirus disease 2019 (COVID-19) pandemic3. Vaccines are an essential countermeasure and are urgently needed to control the pandemic4. Here we show that the adenovirus-vector-based vaccine ChAdOx1 nCoV-19, which encodes the spike protein of SARS-CoV-2, is immunogenic in mice and elicites a robust humoral and cell-mediated response. This response was predominantly mediated by type-1 T helper cells, as demonstrated by the profiling of the IgG subclass and the expression of cytokines. Vaccination with ChAdOx1 nCoV-19 (using either a prime-only or a prime–boost regimen) induced a balanced humoral and cellular immune response of type-1 and type-2 T helper cells in rhesus macaques. We observed a significantly reduced viral load in the bronchoalveolar lavage fluid and lower respiratory tract tissue of vaccinated rhesus macaques that were challenged with SARS-CoV-2 compared with control animals, and no pneumonia was observed in vaccinated SARS-CoV-2-infected animals. However, there was no difference in nasal shedding between vaccinated and control SARS-CoV-2-infected macaques. Notably, we found no evidence of immune-enhanced disease after viral challenge in vaccinated SARS-CoV-2-infected animals. The safety, immunogenicity and efficacy profiles of ChAdOx1 nCoV-19 against symptomatic PCR-positive COVID-19 disease will now be assessed in randomized controlled clinical trials in humans.
【초록키워드】 COVID-19, coronavirus disease, SARS-CoV-2, IgG, Efficacy, Vaccine, coronavirus, Cytokines, Pneumonia, Cellular immune response, nasal, COVID-19 disease, Randomized, Bronchoalveolar lavage fluid, Viral load, mice, symptomatic, humans, disease, expression, ChAdOx1 nCoV-19, rhesus macaques, macaques, T helper cells, rhesus macaque, Evidence, Lower respiratory tract, viral challenge, humoral, regimen, T helper cell, cell-mediated response, acute respiratory syndrome, tissue, profile, Controlled clinical trial, no difference, PCR-positive, immunogenic, ENCODE, robust, responsible, significantly, reduced, the spike protein, demonstrated, ChAdOx1 nCoV-19 against, 【제목키워드】 Vaccine, SARS-CoV-2 pneumonia, rhesus macaque, Prevent,