FIG. 3.
Detection of antibody responses of pigs to AR1, AR2, and AR3 of Erns by ELISA. Twenty serum samples from CSFV-infected pigs and 238 negative pig sera were analyzed for reactivity with immobilized AR1 (A), AR2 (B), and AR3 (C), using the optimized conditions as described in the text. Dilution buffer without testing serum served as a control. The optimum cutoff determined by ROC analysis is indicated by a solid line. A higher cutoff eliminating all false positives (100% specificity) is indicated by a dashed line. The location of each Erns fragment relative to the full-length protein is marked (shaded) in the insets.