Fig. 4: SARS-CoV-2 antibody responses over time.
From: ORF8 and ORF3b antibodies are accurate serological markers of early and late SARS-CoV-2 infection
a–c, Sensitivity performances of N, ORF3b, ORF8 and their sums for early time points before day 14. The contour red line shows the highest sensitivity and specificity (a). Detection of early-time-point patients only (≤day 14) with the sum of three most sensitive antigens (N + ORF3b + ORF8) (b) and ORF3b + ORF8 (c). d, Longitudinal time point patient (n = 14) responses for N (red), ORF3b (pink), ORF8 (green) and S (blue). The x axis represents time point (to scale) after onset of symptoms in days for each patient. On the y axis, each unit represents 103 for ORF3b, ORF8 and S and 106 for N (origin shifted for the sake of clarity). e, Linear regression of full S LU versus ORF8 LU of patients with COVID-19 (from a) (R2 = 0.66902, P < 0.0001, two-sided P value). f, Fold changes from earliest available acute time point sample (from a) to convalescence (14–30 d post-symptom onset) and long-term memory (>31 d post-symptom onset) of S, N, ORF8 and ORF3b LU. *P < 0.05 shows statistical significance by one-sample Student’s t-test versus a hypothetical value of one fold change. g, Percentages of OC43, 229E and NL63 S IgG in the negative cohort. ELISAs were performed on n = 176 COVID-19 negative control cohort samples. Positivity in HCoV ELISA was defined as OD > 1 and negativity as OD < 1.
