Unraveling the long-term kinetics of antibodies to SARS-CoV-2 and the individual characteristics influencing it, including the impact of pre-existing antibodies to human coronaviruses causing common cold (HCoVs), is essential to understand protective immunity to COVID-19 and devise effective surveillance strategies. IgM, IgA and IgG levels against six SARS-CoV-2 antigens and the nucleocapsid antigen of the four HCoV (229E, NL63, OC43 and HKU1) were quantified by Luminex, and antibody neutralization capacity was assessed by flow cytometry, in a cohort of health care workers followed up to 7 months ( N = 578). Seroprevalence increases over time from 13.5% (month 0) and 15.6% (month 1) to 16.4% (month 6). Levels of antibodies, including those with neutralizing capacity, are stable over time, except IgG to nucleocapsid antigen and IgM levels that wane. After the peak response, anti-spike antibody levels increase from ~150 days post-symptom onset in all individuals (73% for IgG), in the absence of any evidence of re-exposure. IgG and IgA to HCoV are significantly higher in asymptomatic than symptomatic seropositive individuals. Thus, pre-existing cross-reactive HCoVs antibodies could have a protective effect against SARS-CoV-2 infection and COVID-19 disease. Long-term characterisation of SARS-CoV-2 antibody kinetics is needed to understand the protective role of the immune response. Here the authors describe antibody levels and neutralisation activity in healthcare workers over seven months and investigate the role of immunity to endemic human coronaviruses.
【저자키워드】 SARS-CoV-2, viral infection, Infection, 【초록키워드】 COVID-19, antibodies, IgG, IgM, immune response, Immunity, antibody, SARS-COV-2 infection, Seroprevalence, healthcare worker, flow cytometry, COVID-19 disease, Cohort, Characteristics, SARS-CoV-2 antibody, Asymptomatic, Surveillance, protective immunity, IgA, symptomatic, Health care worker, NL63, neutralizing capacity, common cold, SARS-CoV-2 antigen, OC43, HKU1, Antibody neutralization, protective effect, anti-spike antibody, nucleocapsid antigen, 229E, Evidence, cross-reactive, individual, post-symptom onset, protective role, characterisation, seropositive individuals, neutralisation activity, endemic human coronaviruses, effective, Seven, human coronavirus, increase, absence, significantly higher, Level, quantified, IgG level, kinetics of antibody, 【제목키워드】 antibody, SARS-CoV-2 antibody, human coronavirus,