Figure 6.

Evaluation of ANT₁ 21-40–reactive antibodies by enzyme-linked immunosorbent assay. Groups of A/J mice were immunized with or without ANT₁ 21-40 twice with an interval of 7 days, and pertussis toxin was administered on days 0 and 2 after the first immunization. Serum samples were collected for measurement of ANT₁ 21-40–reactive antibodies on indicated days. Plates were coated with ANT₁ 21-40 or RNase 43-56 (negative control) overnight at 4°C, and after washing and blocking, 1:10 (top panel) and 1:100 (bottom panel) diluted serum samples were added. Plates were further incubated for 1 hour at 37°C, followed by addition of secondary antibody. After washing and incubating with the substrate, OD values were measured at 450 nm. Data are means ± SEM. n = 3 to 10 individual mice. ^∗∗P < 0.01, ^∗∗∗P < 0.001 versus control groups.