Role of BCAM0224 in cell invasion. (A) Invasion 4 h after infection of the 16HBE14o− (non-CF) and CFBE41o− (CF) epithelial cell lines by the BCAM0224::Tp mutant, expressed as a ratio of B. cenocepacia K56-2 cells (***, P < 0.001; **, P < 0.01). The invasion results for BCAM0224::Tp mutant complementation using plasmid pDM6 and the empty plasmid are shown for both cell lines (***, P < 0.001; **, P < 0.01; *, P < 0.05). (B) Inhibition of epithelial cell invasion was achieved by preincubation of B. cenocepacia K56-2 and the BCAM0223::Tp mutant with anti-BCAM0224 antibody (**, P < 0.01; ***, P < 0.001). No inhibitory activity was observed with an irrelevant rabbit serum, used as a negative control. Results are expressed as a ratio of B. cenocepacia K56-2 values (NS, no statistical significance). All results are from three independent experiments; bars indicate SD.