Rmil 22

C57BL/6 (B6) and IL-33R/ST2 deficient mice were inoculated by gavage with 30 cysts of the 76K strain obtained as described before (13 (link)). Groups of 5 to 8 female mice of 8–12 weeks were used and the studies were repeated twice. Additional groups of mice were injected daily intraperitoneally with 0.5 μg of rm IL-33 (aa 109–266) or 5 μg rmIL-22 daily R&D system). Neutralizing rmIL-22 (R&D system) antibody and IL-33R/ST2 (gift from Dr. Dirk Smith, Amgen) antibody were injected at 50 μg per mouse or isotype control (rat IgG1, R&D system) on days 1, 3, and 5 after oral infection. The mice were analyzed at day 7 for neutrophil recruitment in the ileum and morphological alterations of the proximal ileum and additional groups were used for survival.

Intestinal epithelial cell lines, including SW480, HT29, HCT116, HIEC, Caco2, and MC-38, were purchased from the National Collection of Authenticated Cell Cultures (Shanghai, China). These cells were cultured in 10 cm plates with DMEM supplemented with 100 U/mL penicillin/streptomycin and 10% FBS. For in vitro treatment with rmIL-17A or rmIL-22 (R&D Systems), cells were starved in serum-free medium for 24 h and then switched to culture medium supplemented with 5% FBS in the presence or absence of rmIL-17A (100 ng/mL) or rmIL-22 (100 ng/mL) for 12 h. The pH of the medium was adjusted with HCl or NaOH.

The following materials were obtained from the indicated sources: recombinant murine IL-22 (rmIL-22; R&D Systems, Minneapolis, MN, USA), anti-IL-22 antibody (α-IL-22) (16-7222-85; eBioscience, San Diego, CA, USA), zymosan, fucoidin, methylated bovine serum albumin (mBSA) and complete Freund adjuvant (CFA; Sigma-Aldrich, St. Louis, MO, USA). The drugs were diluted in sterile saline.