Dextran sulfate sodium (dss)

Colitis was induced by feeding mice 5% DSS dissolved in drinking distilled water (mol wt 5000; Wako Pure Chemical Co., Osaka, Japan) for 7 days, as previously described [16] (link).

Colitis was induced in female mice by feeding 2.5% (for SCID mice) or 4% (for C57BL/6J and GFP-LC3#53 mice) DSS (mol wt 5000; Wako Pure Chemical Co., Osaka, Japan) dissolved in drinking water (distilled water). Mice were followed up until day 10, as described previously [74 (link)]. We used 2.5% DSS to induce colitis in C57BL/6J SCID mice because of its high lethality rate in VAD SCID mice. VAD B6 mice were intraperitoneally administered 50 mg/head/day of mAB against IL-1β (Biolegend, San Diego, CA, USA) from day 0 (when DSS treatment was initiated) to day 3. Isotype-matched IgG was injected as a control [75 (link)]. A chemical NLRP3 inhibitor, MCC950 (MedChem Express, Monmouth Junction, NJ, USA), was intraperitoneally administered to mice (10 mg/kg) at day 0 and every two days thereafter [76 (link)]. An autophagy activator (a potent and specific mTOR inhibitor), rapamycin (MedChem Express), was dissolved in ethanol and diluted ≥20-fold with 5% Tween 80 (Sigma-Aldrich, St. Louis, MO, USA) solution containing 5% PEG-400 (Wako Pure Chemical Co.). The drug was administered intraperitoneally to mice (10 mg/kg) daily from days 0 to 7 [77 (link)]. The inhibitors, antagonists, or antibody treatments were co-administered with DSS. We observed no interactions between DSS treatment and other drugs.

Acute colitis was induced by administering 2.0% (w/v) DSS (Wako Pure Chemical Industries, Ltd., Osaka, Japan) orally in drinking water ad libitum for 7 days as described in previous studies.^{(15 (link)–17 (link))} The HO inhibitor, zinc protoporphyrin (ZnPP; Frontier Scientific, Logan, UT) at 25 mg/kg, was injected intraperitoneally daily during DSS administration. The mice were sacrificed on day 7 and their colons were removed for macroscopic, histological, and biochemical examination.