Fig. 3
Effect of time since infection on anti-RBD antibody titer. Relation between SARS-CoV-2 RBD-specific antibody titer from all serum samples (dots) and time in days from SARS-CoV-2 infection to obtaining the serum sample. The colored lines are regression lines of titers, for patients with anti-TNF (rs = -0.27; p = 0.05), other ISP (rs = -0.29; p < 0.01), and controls (rs = -0.32; p < 0.01). Colored dots reflect samples of patients with anti-TNF, other ISP, and controls. AU Arbitrary units, ISP Immunosuppressant, RBD Receptor-binding domain, rs Spearman’s rho, TNF Tumor necrosis factor