Abstract
Background: Coronavirus disease 2019 (COVID-19) is a pandemic with no specific antiviral treatments or vaccines. There is an urgent need for exploring the neutralizing antibodies from patients with different clinical characteristics.
Methods: A total of 117 blood samples were collected from 70 COVID-19 inpatients and convalescent patients. Antibodies were determined with a modified cytopathogenic neutralization assay (NA) based on live severe acute respiratory syndrome coronavirus 2 and enzyme-linked immunosorbent assay (ELISA). The dynamics of neutralizing antibody levels at different time points with different clinical characteristics were analyzed.
Results: The seropositivity rate reached up to 100.0% within 20 days since onset, and remained 100.0% till days 41-53. The total geometric mean titer was 1:163.7 (95% confidence interval [CI], 128.5-208.6) by NA and 1:12 441.7 (95% CI, 9754.5-15 869.2) by ELISA. The antibody level by NA and ELISA peaked on days 31-40 since onset, and then decreased slightly. In multivariate generalized estimating equation analysis, patients aged 31-45, 46-60, and 61-84 years had a higher neutralizing antibody level than those aged 16-30 years (β = 1.0470, P = .0125; β = 1.0613, P = .0307; β = 1.3713, P = .0020). Patients with a worse clinical classification had a higher neutralizing antibody titer (β = 0.4639, P = .0227).
Conclusions: The neutralizing antibodies were detected even at the early stage of disease, and a significant response was shown in convalescent patients.
Keywords: COVID-19; SARS-CoV-2; convalescent patient; neutralizing antibody.
【저자키워드】 COVID-19, neutralizing antibody, SARS-CoV-2, convalescent patient, 【초록키워드】 coronavirus disease, neutralizing antibody, Coronavirus disease 2019, coronavirus, pandemic, Vaccines, Clinical characteristics, Neutralizing antibodies, antibody, Antiviral treatment, ELISA, enzyme-linked immunosorbent assay, Convalescent patients, Neutralization assay, Patient, Antibody titer, Seropositivity, respiratory, convalescent, disease, early stage, convalescent patient, Neutralizing antibody titer, Analysis, geometric mean, Inpatient, acute respiratory syndrome, 95% CI, acute respiratory syndrome coronavirus, acute respiratory syndrome coronavirus 2, 95% confidence interval, Blood samples, enzyme, different time points, blood sample, multivariate, geometric mean titer, enzyme-linked immunosorbent, shown, analyzed, collected, peaked, remained, reached, different time point, 【제목키워드】 Coronavirus disease 2019, coronavirus, coronavirus 2, response, respiratory, Inpatient,