Fig. 3

Exposure of pBECs to NT H. influenzae or P. aeruginosa enhances IL-6 release. PBECS of seven donors were pre-exposed to heat-inactivated preparations of non-typeable (NT) H. influenzae (a), P. aeruginosa (b), or S. pneumoniae (c) for 24 h, after which bacteria were washed away and cells were infected with RSV for up to 72 h. IL-6 levels in culture supernatants 24, 48 and 72 h after viral infection were determined by ELISA. Due to considerable inter-individual variation in absolute cytokine levels, data are shown as relative changes of experimentally determined cytokine concentrations over the theoretical additive effect for each donor. Results obtained using cells from each donor are denoted with the same symbol in all datasets. hpi: hours post viral infection