Fig. 7

Knock-out of SLO in 5448 leads to elevated secretion of IL-1β and IL-18 by moDCs. A SLO hemolytic activity in supernatants of 5448 and 5448AP strains. MoDCs were infected with 5448 or 5448Δslo and moDC viability (B) and phenotype (C–E) were evaluated via flow cytometry. The maturation process was evaluated by assessing the frequencies of CD83⁺ (C) and CD86⁺ (D) cells as well as expression of HLA-DR (E). Representative histograms for each marker are shown in each respective left panel. The concentrations of IL-8 (F), IL-1β (G), and IL-18 (H) were measured in supernatants of (un)infected moDCs. The data in (B–H) are displayed as box plots. Each dot represents one independent experiment with cells from one donor (n ≥ 6). The level of significance was determined using Kruskal–Wallis test with Dunn’s posttest. FMO, fluorescence minus one; MFI, mean fluorescence intensity