Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of Coronavirus Disease 2019 (COVID-19), has caused a global pandemic, and safe, effective vaccines are urgently needed1. Strong, Th1-skewed T cell responses can drive protective humoral and cell-mediated immune responses2 and might reduce the potential for disease enhancement3. Cytotoxic T cells clear virus-infected host cells and contribute to control of infection4. Studies of patients infected with SARS-CoV-2 have suggested a protective role for both humoral and cell-mediated immune responses in recovery from COVID-19 (refs. 5,6). ChAdOx1 nCoV-19 (AZD1222) is a candidate SARS-CoV-2 vaccine comprising a replication-deficient simian adenovirus expressing full-length SARS-CoV-2 spike protein. We recently reported preliminary safety and immunogenicity data from a phase 1/2 trial of the ChAdOx1 nCoV-19 vaccine (NCT04400838)7 given as either a one- or two-dose regimen. The vaccine was tolerated, with induction of neutralizing antibodies and antigen-specific T cells against the SARS-CoV-2 spike protein. Here we describe, in detail, exploratory analyses of the immune responses in adults, aged 18–55 years, up to 8 weeks after vaccination with a single dose of ChAdOx1 nCoV-19 in this trial, demonstrating an induction of a Th1-biased response characterized by interferon-γ and tumor necrosis factor-α cytokine secretion by CD4+ T cells and antibody production predominantly of IgG1 and IgG3 subclasses. CD8+ T cells, of monofunctional, polyfunctional and cytotoxic phenotypes, were also induced. Taken together, these results suggest a favorable immune profile induced by ChAdOx1 nCoV-19 vaccine, supporting the progression of this vaccine candidate to ongoing phase 2/3 trials to assess vaccine efficacy.
【초록키워드】 COVID-19, neutralizing antibody, SARS-CoV-2, Efficacy, Vaccine, coronavirus, immune response, vaccination, Trial, Immune profile, CD8+ T cells, progression, SARS-CoV-2 vaccine, Spike protein, Adenovirus, global pandemic, Adults, AZD1222, Patient, vaccine candidate, IgG3, disease, T cell response, CD4+ T cell, ChAdOx1 nCoV-19, IgG1, single dose, ChAdOx1 nCoV-19 vaccine, Protective, Safe, humoral, antibody production, Cytotoxic T cell, antigen-specific T cell, host cell, Phenotypes, interferon-γ, tumor necrosis factor-α, phase 2/3 trial, acute respiratory syndrome, Exploratory analysis, protective role, immunogenicity data, cell-mediated immune response, two-dose regimen, cytokine secretion, caused, reported, characterized, contribute, suggested, effective vaccine, reduce, expressing, Strong, cell-mediated immune, full-length SARS-CoV-2, infected with SARS-CoV-2, the SARS-CoV-2, 【제목키워드】 Vaccine, clinical trial, Antibody Response, T cell, AZD1222, ChAdOx1 nCoV-19, single dose,