FIG 4.

Antibodies that targeted NTHI PilA disrupted established NTHI+Mcat biofilms. Biofilms were established for 24 h; then exposed to anti-OMP P5, anti-rsPilA, or anti-chimV4 or maintained in medium (sBHI) for 16 h; and then visualized by CSLM. COMSTAT2 analysis of NTHI+Mcat biofilms formed at 34°C (A) or 37°C (B) revealed a significant reduction in biomass and mean thickness after exposure to anti-rsPilA or anti-chimV4, but not anti-OMP P5 or naive serum. In contrast, biofilms formed by Mcat alone showed no significant effect of any antiserum on biomass or mean thickness at either 34°C (C) or 37°C (D). These results demonstrated that NTHI+Mcat biofilms formed at either 34°C or 37°C were disrupted by antisera that target the NTHI Tfp. Data represent mean ± SEM from 3 experiments performed in duplicate. Statistical significance was determined by one-way analysis of variance with the Holm-Sidak correction. **, P ≤ 0.01; ***, P ≤ 0.001; ****, P ≤ 0.0001.