FIG. 3.

Correlation between the levels of IgG, IgM, and IgA antibodies to T. gondii as determined by indirect ELISA using STAg and reverse ELISA using anti-SRS (A, D, G), anti-SAG2A (B, E, H), and anti-p97 (C, F, I) MAbs in human sera. A total of 140 serum samples (groups I, II, and III) were analyzed for IgG, 85 serum samples (groups I and II) for IgM, and 35 serum samples (group I) for IgA. The correlation coefficients (r_s) were calculated by the Spearman correlation test. The dashed lines indicate the cutoff values (EI > 1.2) for each assay. The percentages of double-positive, double-negative, and single-positive samples for each antibody isotype are indicated on the corresponding corners.