Figure 6

Treatments that disrupt tight junctions increase the PAO1-stimulated IL-8 response, but not the TNF-α/IL-1β stimulated response of CF-phenotype cells. 16HBEo- Sense (open bars) and Antisense (black bars) monolayers on filters were pretreated for 60 minutes with 30 mM EGTA prior to 1 hr. stimulation with 10⁹ CFU PAO1/(EGTA, n = 5 independent experiments, each with triplicate wells), or an overnight incubation with 250 μg monoclonal antibody to E-Cadherin (ECAD, n = 3 independent experiments, each with triplicate wells), and the IL-8 (A, C) and IL-6 (B, D) response measured 24 H later by ELISA. The IL-8 response to PAO1 was significantly (*) increased in the 16HBE-Antisense cells following pretreatment with E-Cadherin antibody (p = 0.034) or EGTA (p < 0.001). The 16HBEo-AS cells produced significantly more IL-8 than their sense congeners (p < 0.05). There was a significant (*) reduction in the IL-6 (p = 0.05) and IL-8 (p = 0.041) response to TNF-α/IL-1β after overnight incubation to the E-cadherin antibody (n = one experiment of triplicate wells). There is a significant increase of IL-8 in response to PAO1 prior to treatment in the CF phenotype cells compared to normal (p = 0.001).