FIGURE 5.

PfbB promotes C1q‐dependent adhesion to epithelial and endothelial cells. (a–c) monolayers of respiratory epithelial (A549, hep‐2) and brain microvascular endothelial (hCMEC/D3) cell lines were infected with pneumococcal strain D39 or its isogenic pfbB mutant in the presence (10 μg) or in the absence of C1q. Adhering bacteria were measured by colony‐forming units (CFU) counts. In some experiments (panels d and e) bacteria were pretreated with a pool of sera from animals immunized with C‐SSURE recombinant repeat (anti‐SSURE) or with a normal serum pool (normal). Shown are means ± SDs of three independent experiments conducted in triplicate. *p < 0.05 by Mann–Whitney test.