Figure 2.

Antibody-induced latex particle agglutination correlates with the antibody titer

(A and B) Changes in agglutination in response to increased concentrations of the anti-S-RBD (n = 3) (A) or anti-N antibody (n = 3) (B). Dashed lines represent fitted curves to the Hill equation (h, Hill coefficient).

(C and D) S-RBD (C) or N (D) antibody-induced agglutination decreased with increased dilution of plasma. Shown are agglutination data (in log₂ scale) from COVID-19⁺, COVID-19⁻, and pre-COVID-19 plasma samples with 1:2 to 1:128 dilution. Data shown are from three replicates per concentration for three samples per group. Error bars represent standard deviation.