Fig. 6.

Inhibition of erythrocyte invasion by sera from mice immunized with the different antigen formulations. Mice were immunized as described in Fig. 3. Pooled sera of the different mice groups were added (1:10, final concentration) in triplicate to wells containing B. bovis-infected erythrocytes that were cultured in vitro. Percentages of parasitized erythrocytes (PPE) were evaluated in Giemsa-stained smears. The results are expressed as the mean PPE ± standard error values that were obtained after 72 h in each condition. The results are representative of two independent experiments. Asterisks denote statistically significant differences in PPE: * P < 0.001 for rMSA-2a₁ sera; P = 0.008 for rMSA-2b sera; P < 0.001 for rMSA-2c sera; P < 0.001 for the sera from mixture of three proteins; compared to cultures incubated with medium only; and ^¥ P = 0.006 compared to cultures incubated with sera from mice immunized with the mixture of three proteins