Figure 1. Fractionated P. aeruginosa supernatant inhibits TLR5 activation.

HEK/TLR5 cells were transfected with a NF-κB reporter construct. Cells were incubated with 20-fold diluted elution fraction from a Q sepharose column (inhibitor) for 30 min and subsequently challenged with various concentrations recombinant flagellin of S. Typhimurium (□). Flagellin without inhibitor (▪) and LPS (•). (A) After 6 h the IL-8 concentration in the cell culture supernatant was measured by ELISA. (B) NF-κB activation was determined by measuring luciferase activity in a luminometer and expressed as fold increase of luciferase activity over stimulation with culture medium alone. The presented data are representative for the inhibition of TLR5 signaling that is typically observed with purifications of P. aeruginosa supernatant.