FIG 6.

Ex vivo mucosal cytokine response(s) to C. difficile RT017 CF5 and M68. Macroscopically normal and matched multiple colonic biopsy specimens (30 individuals with mean age of 10.4 ± 4.7 [the standard deviation]) were cocultured with C. difficile CF5 and M68 (5 × 10⁸) for 6 h. Postinfection, IL-6 (A), IL-8 (B), IL-1β (C), IFN-γ (D), IL-17A (E), and IL-22 (F) were quantified by ELISA in duplicate. The bars represent the median levels. *, P < 0.05; ***, P < 0.001 (significant differences from uninfected controls). ^, P < 0.05 (a significant interstrain difference). The data were analyzed by using a Mann-Whitney U test.