Fig 3.

IgM and IgG recognition of dominant epitopes that contribute to long-term antibody responses in SARS-CoV-2–infected individuals. Longitudinal analysis of serum recognition of epitopes in 19 individuals with COVID-19 using a peptide microarray covering the proteome of SARS-CoV-2. The cutoff value for the positive response of peptide binding in patient samples (n = 51) was set as twice the signal intensity of the pooled sera from 20 healthy donors. A, Peptide counts and distribution of positive binding peptides that were detectable in 1 or more samples collected at 10-60 days (n = 18), 100-150 days (n = 18), and 180-220 days (n = 15) after disease onset. Numbers indicate the total identified IgG and IgM epitopes from each ORF. B, Signal intensities of dominant and persistent IgG and IgM epitopes (x-axis) that were sustainably reactive in more than 80% samples within all 3 sampling time points. Each dot indicates the pooled sera from healthy donors (top) or a distinct patient serum sample collected from indicated time points after symptom onset. E, Envelope protein.