Figure 2. Bactericidal antibody titers (A) and opsonic antibody response measured as median fluorescence induced during the oxidative burst of neutrophils (B) to the vaccine strain Cu385/83, a P1.15,19 homologous strain (H355/75; B:15:P1.19,15) and its variants Opa- and PorA-. Serum samples were obtained 14 days after the third immunization. For bactericidal antibody titers (A), the data are the mean ± SE of three serum pools. Each pool contained serum from 3 individuals. For opsonic antibodies (B), the data are the median and range of values of 6 mice. *P < 0.05 (Wilcoxon matched-pair test) compared to Cu385, H355 and to H355 Opa- strains.
