Figure 1

C. difficile R20291 flagella are involved in caecal inflammation of mice. C57BL/6 mice (n = 10) were infected or not and caeca were collected at the clinical end point day 2 for histology. (A) Representative histology of caecum of healthy uninfected mice (control) with epithelium integrity; (B) R20291 WT-infected mice with ulcerative colitis, necrosis, desquamation, exudates and necrotic cells in the intestinal lumen, edema, inflammatory submucosal cell infiltration, loss of architecture of epithelium and presence of pseudomembranes in caecum; (C) R20291 fliC and (D) A⁻B⁻ mutant-infected mice with edema, focal desquamation of necrotic cells in the intestinal lumen and submucosal cell infiltrate; (E) R20291 motB mutant-infected mice with similar degree of mucosal lesion than R20291 WT-infected mice (200X magnification). Bar = 200 µm. (F) Inflammation histological scores for individual mice in each group. The horizontal lines represent the mean scores for each group of animals. (G) Individual evaluation criteria of intestinal inflammation. The bars represent the mean scores for each group of animals and standard deviations. *P < 0.01 compared to WT-infected mice.