FIG. 6.

(Top) Correlation between the PorA antigen-induced T-cell proliferation (cpm) and concentrations of IgG antibodies to OMVs in serum from 12 volunteers intranasally immunized with a meningococcal OMV vaccine without adjuvant (15). Each symbol represents the maximum responses obtained after vaccination for one individual. (Bottom) Correlation between the PorA antigen-induced T-cell proliferation (cpm) and titers of serum bactericidal activity (SBA) in the same vaccinees as in the top panel. Each symbol represents the values obtained before or the maximum response values obtained after vaccination for one individual. The reciprocal value of the highest serum dilution causing more than 50% killing of an inoculum of 44/76 meningococci was recorded as the bactericidal titer, and log₂ titers are shown. External human plasma was used as the complement source.