Il 10

Thirty healthy male rabbits, weighing between 1.80–2.20 kg, were obtained from the Experimental Animal Center of the University of South China (Henyang, China). They were kept in standard conditions with free access to food and water. All animal experiments were conducted according to the ethical guidelines of the University of South China.
Escherichia coli (ATCC 25922) was provided by the Department of Microbiology of the Second Affiliated Hospital of University of South China (Henyang, China). NaHS was purchased from Sigma (St. Louis, MO, USA). TNF-α, IL-10 and NF-κB antibodies were obtained from Beijing Biosynthesis Biotechnology, Co., Ltd. (Beijing, China). Rabbit SP-HRP (streptavidin-biotin-peroxidase) kit and 3,3′-diaminobenzidine (DAB) chromogenic kit were provided by Beijing Kangwei Century Biotech Co., Ltd. (Beijing, China).

The livers and spleens of mice were surgically removed, paraffin-embedded, and sectioned (4 μm). Hematoxylin and eosin (HE) staining was performed to assess the histopathological condition of the tissues and confirm liver metastasis. The localization of IL-10 (Beijing Biosynthesis Biotechnology, Beijing, China) and TGF-β1 (Bioworld Technology Inc., St Louis Park, MN, USA) was visualized by immunohistochemical staining as previously described [22 (link)]. Tissue sections (4 μm) were prepared from formalin-fixed, paraffin-embedded tissues. After deparaffinization and rehydration for antigen retrieval, slides were heated in 10 mM citrate buffer (pH 6.0) in a microwave oven or pressure cooker and cooled to room temperature.