Figure 4.

The ex vivo effects of H-D-Pro-Phe-Arg-CMK on the generation of bradykinin by kaolin and Salmonella. Human plasma samples, in the absence or presence of H-D-Pro-Phe-Arg-CMK (100 μg/ml final concentration), were incubated with kaolin or with strains SR11B, CsgA, or CsgB for 15 min. Plasma was removed by centrifugation and kaolin or bacteria were resuspended as described in Materials and Methods. After 15 min of incubation, the amount of bradykinin present in the reaction mixture was measured by a competitive ELISA. As a control, plasma was incubated in the absence of kaolin and bacteria. Data represent means ± SD of three experiments. P values between SR11B and CsgA or CsgB are indicated in the figure.