Quantification of IL-6 and IL-8 secretion by CBA analysis. Interleukin-6 (A) and interleukin-8 (B) concentrations in tissue culture supernatants of control cells and HUVECs incubated with Stx1 or Stx2 for 4 hours and 24 hours, measured by cytometric bead array. Data are presented as mean from 3 independent experiments.