Skip to main content
. 2009 Aug 31;4(8):e6834. doi: 10.1371/journal.pone.0006834

Figure 3. Adhesion monitoring of meningococci to ME180 cells upon IPTG-mediated PilC1 or PilC2 induction:

Figure 3

Semi-confluent ME180 cells are monitored prior to (pre-infection) and during infection with Nm2C4.3 derivatives NmPilC1ind and NmPilC2ind that express virtually no PilC in the absence of induction. Infection (MOI 50) is initially carried out in the absence of IPTG for approximately 2 hours (no induction), and continued after addition of IPTG (20 min post IPTG). No meningococcal adhesion to ME180 cells is visible until expression of PilC1 or PilC2 is induced, despite heavy bacterial load due to replication over the experiment. Within minutes following addition of IPTG, all cells are covered with adhering bacteria in the case of PilC1-mediated infection, whereas only a fraction of ME180 cells are associated with PilC1-/PilC2+ meningococci (arrows).