2.5. Peptide adsorption of patients’ sera
To verify reactivity of RBD-specific and NP-specific antibodies to the identified peptides from both proteins, a depletion assay was performed. Using principles similar to the previous section, we performed peptide adsorption as follows. P151-170 of NP and P204-223 of RBD were selected as the immunodominant peptides. P136-155 of NP and P196-215 of RBD were selected as non-reactive irrelevant control peptides. 2.0 µg/ml of selected peptides were incubated with the patient’s sera for 3 h at 37 °C to adsorb peptide-specific antibodies. Peptide-adsorbed patients’ sera were then incubated for 1h at 37°C in NP or RBD pre-coated ELISA plates. ELISA analysis was performed as described in section 2.4. Non-adsorbed sera were added as control.