Figure 7.

Humoral response after threefold immunization with the recombinant ribosomal P. falciparum proteins. Two weeks after each vaccination (denoted here as I, II, and III), the levels of antibodies were measured: total IgG (a), IgG1 (b), and IgG2a (c). The antibody titer was characterized as the reciprocal of the highest serum dilution factor corresponding to a mean absorbance value of 0.1. Each data is presented as the mean ± S.E.M. of six mice. The differences were analyzed statistically with the Kruskal-Wallis test followed by the Dunn multiple comparison test. Significantly different from (+) the first immunization or (++) the second immunization with the same protein, P ≤ 0.05.