Fig. 7

IL-6 production is crucial for LPS-induced effects. A. The mRNA and protein expression of claudin-1 following IL-6 stimulation (400 ng/ml). Claudin-1 mRNA expression: Ctrl vs. IL-6: 1.0 ± 0.0 vs. 0.8 ± 0.0, P < 0.001; claudin-1 protein expression: Ctrl vs. IL-6: 1.2 ± 0.3 vs. 0.8 ± 0.1, P < 0.01. B. The intercellular space shown by H&E staining following IL-6 stimulation (400 ng/ml). Ctrl vs. IL-6: 0.4 ± 0.3 μm vs. 1.3 ± 0.3 μm, P < 0.01. C. The mRNA and protein expression of claudin-1 after treated with IL-6 antibody (0.1 ng/ml). Claudin-1 mRNA expression: Ctrl vs. LPS vs. LPS ± IL-6 IgG vs. IgG = 1.0 ± 0.0 vs. 0.8 ± 0.0 vs. 1.1 ± 0.0 vs. 1.0 ± 0.0, P < 0.001; claudin-1 protein expression: Ctrl vs. LPS vs. LPS ± IL-6 IgG vs. IgG = 1.2 ± 0.1 vs. 0.8 ± 0.1 vs. 1.2 ± 0.3 vs. 1.1 ± 0.1, P < 0.05. D The intercellular space shown by H&E staining after treated with IL-6 antibody (0.1 ng/ml). Ctrl vs. LPS vs. LPS ± IL-6 IgG vs. IgG = 0.2 ± 0.1 μm vs. 1.4 ± 0.0 μm vs. 0.4 ± 0.1 μm vs. 0.2 ± 0.1 μm, P < 0.001. Abbreviation: Ctrl: control; IL: interleukin; LPS: lipopolysaccharide; DIS: dilated intercellular space; *: P < 0.05; **: P < 0.01; ***: P < 0.001