FIG. 3.

ELISA detection of antibodies to p135-160 (A) and anti-FMDV particles (B) in mice immunized with transformed plants. Briefly, the assay was performed exactly as described previously for detection of VP1 in transgenic plants regarding the capture of antigen to the plate and the blocking, washing, developing, and reading steps (20). Antigen was added after the capture antibody (p135-160 at a concentration of 10 μg/ml and purified inactivated FMDV at a concentration of 1 μg/ml) and incubated for 1 h at 37°C. Sera were tested in a fourfold dilution series in blocking buffer. Serum titers are expressed as the log of the reciprocal of the highest serum dilution which presents optical density (OD) readings above the mean OD readings plus 5 standard deviations of sera from five animals immunized with plants transformed with pRok.