FIG. 6.

S-pilin inhibits adherence of P⁺ gonococci to target cells. ME180 cells were preincubated with S-pilin (2 μg/ml) for 30 min prior to the addition of piliated N. gonorrhoeae MS11. Binding was allowed to occur for 1 h, and bound bacteria were detected with gonococcal antiserum and FITC-conjugated IgG. The control shows adherence of P⁺ MS11 to ME180 cells preincubated with supernatant of a pilE derivative of MS11-8 for 30 min. Bound bacteria were counted on 100 randomly selected cells. Shown are the average of four independent experiments and the standard deviation.