C. rodentium Infection Model in Mice

Sex matched, 8 to 10 week old mice, fasting for 8 hr, were orally gavaged with 1.2 × 10¹⁰ cfu of C. rodentium strain DBS100 (ATCC 51459). In certain instances, mice were intraperitoneally injected with 200 μg of murine LTβR-IgG1 fusion protein or MOPC21 isotype control (Biogen Idec) 1 day prior to infection, as described (Wang et al., 2010 (link)). IECs, isolated following published procedure (Greten et al., 2004 (link)), were utilized for biochemical analyses. For histology, dissected colons were fixed in 10% neutral buffered formalin. Paraffin-embedded tissue sections were stained with anti-myeloperoxidase antibody (Pierce, Waltham, Massachusetts, USA) for neutrophil recruitment or with Hematoxylin and Eosin (H&E) for tissue pathology evaluation. Fecal samples were weighed, homogenized, and serially diluted homogenates were plated on MacConkey agar (HiMedia, Mumbai, India) to score for C. rodentium. Similarly, spleens and livers were aseptically removed and assessed for bacterial load. For bone marrow chimera experiment, recipient WT or Nfkb2^−/− mice were lethally irradiated and marrow cells from the indicated donor mice were transferred. After 6–8 weeks, mice were infected.