Figure 4.

Binding to and complement (C´)-dependent bactericidal activity mediated by FH6,7/Fc against nine clinical strains of N. gonorrhoeae. A. Binding of FH6,7/Fc to N. gonorrhoeae. Binding of FH6,7/Fc (10 µg/ml) to each of the nine gonococcal isolates listed on the X-axis (identified in the Table) was measured by flow cytometry. Binding (Y-axis) is shown as fold-increase over conjugate controls. The mean (range) of at least two separate experiments is shown. B. Complement-dependent bactericidal activity mediated by FH6,7/Fc. The nine strains of N. gonorrhoeae were incubated with either 20% C´ alone (black bars) or C´ plus FH6,7/Fc (33 µg/ml) (grey shaded bars) and percent survival (Y-axis) at 30 min was measured. Each bar represents the mean (range) of at least two independently performed experiments.