Immunohistochemistry kit

One hour after the last injections of caerulein, the mice were sacrificed with the blood from the inferior vena cava extracted and pancreatic tissues separated. The samples were then fixed, dehydrated and made into paraffin‐embedded sections. According to the instructions of immunohistochemistry kit (# SA1054, BOSTER Biological Technology Co. Ltd., Wuhan, Hubei, China), the sections were subjected to retrieval repair with the citric acid antigen, washed thrice with PBS, blocked at room temperature for 20 min and incubated with the primary antibody at 4℃ overnight. The next day, the sections were cultured with the secondary antibody at room temperature for 45 min. Finally, the sections were stained with DAB and the nucleus was stained with haematoxylin. The images were observed and photographed under a microscope (Olympus Optical Co., Ltd, Tokyo, Japan). Myeloperoxidase‐Anti (MPO) antibody was purchased from Abcam (1:500, ab208670).

Azoxymethane (AOM) and DSS (MW 36,000–50,000) were obtained from Sigma-Aldrich (St Louis, MO, USA). Maxima^® SYBR Green/ROX qPCR Master Mix (2×) and Maxima^® First Strand cDNA Synthesis Kit were purchased from Fermentas life science (Waltham, MA, USA). Immunohistochemistry kit and myeloperoxidase (MPO) (m) ELISA Kit were purchased from Boster (Wuhan, Hubei, China.).

After dewaxing with xylene, kidney paraffin sections were immersed in gradient alcohol and water before staining, then soaked in 3% H₂O₂ to remove endogenous peroxidase. All sections were heated in sodium citrate solution for 15 min in 98°C for antigen retrieval. Then the tissue specimens were circled with an immunohistochemical pen, added 5% bovine serum albumin (BSA) solution, and blocked at 37°C for 30 min, incubated with the primary antibodies including fibronectin (1:500, abcam, ab268021, United Kingdom, Cambridge), alpha smooth muscle actin (1:300, abcam, ab7817, United Kingdom Cambridge), collegen-I (1:500, abcam, ab270993, United Kingdom, Cambridge) solution 200 μL at 4°C overnight. After washing off, these tissues were incubated with secondary antibody solution at 37°C for 40 min, colored by 3,3′-diaminobenzidine (DAB) under a microscope and counterstained with hematoxylin (Cat. No. C0105S, Beyotime Biotechnology, Shanghai, China). The immunohistochemistry kits were purchased from Boster Biotechnology (Fujian, China). DAB color reagent kits were purchased from Maixin Biotechnology (Fujian, China).

Trizol reagent, RNAios and Real-time PCR kit were obtained from TaKaRa Company (Dalian, China). Anti- MyD88, anti-TRAF6, anti-TRIF and anti-TLR4 antibodies were offered from Abcam Biotechnology (MA, USA). LPS was taken from Sigma-Aldrich (MO, USA). The immunohistochemistry kits and HRP-labeled secondary antibodies were bought from Boster Biotechnology (Wuhan, China). The IL-1β and IL-6 ELISA kit were purchased from Dkewei Biotechnology (Beijing, China). Corilagin was received from China National institutes for food and drug control.