<i>N. gonorrhoeae-</i>specific bactericidal activity of relevant antibodies detected using antibody-mediated complement-dependent bactericidal activity assay.

<p>50 µl of serially diluted antiserum and 40 µl of bacterial suspension were mixed and incubated for 15 min. After adding 10 µl of fresh human serum as the complement, the suspension was incubated for another 45 min. The survival cells in the mixture were counted on GC chocolate agar plates. Relative survival rate was derived from the ratio of the number of colonies in the antiserum incubation group to that in the normal serum incubation group, and antiserum was defined as having significant bactericidal effects in case the rate was lower than 50%. For all groups, n = 4. Error bars were drawn as mean with standard deviation.