FIG. 1.
Kinetics of the (A) IgG response and (B) IgG1 or IgG2a response elicited after immunization with the rOmp31 vaccine. Mice were immunized with rOmp31 in incomplete Freund's adjuvant and bled retroorbitally on the indicated days. Specific Abs against rOmp31 were evaluated by ELISA. Each symbol represents the mean ± SD of eight animals. The arrow indicates the time of B. ovis infection. Determination of IFN-γ (C) or IL-2 (D) production in cells from PBS- or rOmp31-immunized mice. Spleen cells (4 × 106/ml) from mice were stimulated with complete medium (RPMI) or rOmp31 (1 μg/ml) or ConA (2.5 μg/ml) for 48 h. IFN-γ or IL-2 in cell supernatants was quantified (pg/ml) by MAb capture ELISA. Each value represents the mean plus SD of the responses of spleen cells from five individual mice. The data are representative of three separate experiments. ★, significantly different from the same stimulus in PBS-immunized mice (P < 0.01).