Anti-SARS-CoV-2 antibody response
Serum was isolated from capillary blood samples (fingerpick sampled at home) taken before the first and the second vaccination and four weeks after the third vaccination, or from venous blood sample drawn four weeks after the second vaccination. SARS-CoV-2-specific anti-RBD IgG antibodies were measured using an in-house (Sanquin, Amsterdam, the Netherlands) enzyme-linked immunosorbent assay (ELISA) assay, as described by Steenhuis et al. (