KLPJ isolated from the colon tissues of patients with UC induces production of mature IL18 in colon epithelial cells. (A) Hybridization of fluorescent KLPJ probe and relationship between the Mayo index and KLP copies in the colitis tissues of patients with UC (n = 50). The relationship between the Mayo index and KLP copies was analyzed using correlation and regression (GraphPad). R2, Pearson correlation coefficient. Green, K pneumoniae probe; blue, nuclei. Control probes indicate fluorescence-labeled control probes. Scale bar: 40 μm. (B) Composition of bacteria in the colitis tissues of patients with UC. A total of 628 bacterium clones from the colon tissues of 12 patients with UC were cultured and analyzed. (C) Western blot of IL18 in the colon epithelial cells after exposure to KLPJ. Colons were isolated and exposed to different bacteria, and then colon epithelial cells were analyzed. (D) ELISA of IL18 in the colon contents after exposure to KLPJ. Colons were exposed to different bacteria, and then colon contents were analyzed. Student t test. ∗P < .05, ∗∗P < .01, and ∗∗∗P < .001. A. vero, A veronii; Ctr, control; HC, healthy colon tissues; MI, Mayo index; UC, tissues of ulcerative colitis; vehicle, control.