FIG. 5.

Functional activity of sera obtained after immunization of mice with several OpaJ-containing liposome formulations tested in SBA assays using Opa⁺ cells of N. meningitidis strain H44/76 of immunotype L3. The data represent the geometric mean (horizontal line), the SBA titers of individual mice, and the number of responder mice/group. Results are given for the sera of mice immunized with OpaJ-containing liposomes alone (control), with OpaJ-containing liposomes adjuvanted with AlPO₄ at 0.5 mg/ml (control + AlPO₄), or with the different LPS species (with dose/mouse indicated in parentheses) incorporated or not into liposomes. Statistically significant differences between sera groups are marked with one asterisk (P < 0.05). SBA titers were considered positive at serum dilutions higher than 10.