Fig. 2
Casp8ΔIEC mice are highly susceptible to Salmonella Typhimurium infection and develop severe enteritis. a–i Control (Casp8fl) (n = 4) and Casp8ΔIEC mice (n = 4) were mock treated or infected with 109 CFU of Salmonella Typhimurium (ΔaroA, attenuated). d–i Data derived at day 3 of infection. Experiments were repeated three times with similar results. a Body weight curve of animals. Data are displayed in percent relative to initial body weight ± SD. b Kaplan–Meier survival curve of control (Casp8fl) and Casp8ΔIEC mice, *p ≤ 0.05. c Representative endoscopic pictures of control (Casp8fl) and Casp8ΔIEC mice 4 days after infection. d Representative pictures and statistical analysis of colon shortening (n ≥ 3 per group; scale bar: 1 cm, **p ≤ 0.01). e Representative H&E stained colon cross sections of mock treated and infected animals (scale bar: 100 µm) and colon cross sections stained with an antibody against activated CASP3 (red) combined with TUNEL assay (green). Nuclei were counterstained with Hoechst 33342 (blue) (scale bar: 100 µm). f Pathology score [maximum: 9] of uninfected and infected colon tissue of control (Casp8fl) and Casp8ΔIEC mice. Data are displayed as mean value + SD, n ≥ 3 per group, **p ≤ 0.01, ***p ≤ 0.001. g Representative images of colon cross sections stained with an antibody against β-Catenin (CTNNB1) (red) and counterstained with Hoechst 33342 (blue) (scale bar: 75 µm). h Serum concentration of orally administered FITC-Dextran in control (Casp8fl) and Casp8ΔIEC mice. Serum was separated from the collected blood and the concentration of FITC-dextran was determined by spectrophotofluorometry with an excitation of 485 nm and an emission of 528 nm using a serially diluted FITC-dextran standard. Data are displayed as individual values with indicated mean values ± SD (n ≥ 5 per group, data are combined from two independent experiments). i Quantification of colonic Villin mRNA expression (n ≥ 3 per group). Error bars indicate + SD, gene expression levels are shown relative to Hprt, *p ≤ 0.05
