BACKGROUND & AIMS: Activation of lamina propria T cells with pokeweed mitogen in human fetal gut explant cultures results in severe mucosal injury. In the same system, Staphylococcus aureus enterotoxin B produces villus atrophy and crypt cell hyperplasia. The aim of this study was to examine the ability of interleukin (IL)-10 to modify these changes. METHODS: Mucosal pathology and lamina propria glycosaminoglycans were assessed histologically, and CD3(+), CD25(+) and alpha-actin smooth muscle-positive cells were determined by immunohistochemistry. Reverse plaque assays and quantitative reverse-transcriptase polymerase chain reaction were used to analyze the cytokine response. Matrix metalloproteinase production was analyzed by Western blotting, in situ hybridization, and zymography. RESULTS: Both experimental enteropathies produced mucosal damage, although injury was greater after pokeweed mitogen activation than S. aureus enterotoxin B. In both cases, the increase in cytokine-secreting cells and transcripts observed after T-cell activation was inhibited by IL-10. IL-10 also inhibited the increase in collagenase and stromelysin-1 in the explant culture supernatants and the loss of glycosaminoglycans. IL-10 decreased metalloproteinase production in control explants and increased matrix. In mesenchymal cells, IL-10 had a minor effect on metalloproteinase production. CONCLUSIONS: IL-10 down-regulates mucosal T-cell activation, metalloproteinase production, and loss of extracellular matrix and prevents mucosal damage in the gut.
BACKGROUND & AIMS: Activation of lamina propria T cells with pokeweed mitogen in human fetal gut explant cultures results in severe mucosal injury. In the same system, Staphylococcus aureus enterotoxin B produces villus atrophy and crypt cell hyperplasia. The aim of this study was to examine the ability of interleukin (IL)-10 to modify these changes. METHODS: Mucosal pathology and lamina propria glycosaminoglycans were assessed histologically, and CD3(+), CD25(+) and alpha-actin smooth muscle-positive cells were determined by immunohistochemistry. Reverse plaque assays and quantitative reverse-transcriptase polymerase chain reaction were used to analyze the cytokine response. Matrix metalloproteinase production was analyzed by Western blotting, in situ hybridization, and zymography. RESULTS: Both experimental enteropathies produced mucosal damage, although injury was greater after pokeweed mitogen activation than S. aureus enterotoxin B. In both cases, the increase in cytokine-secreting cells and transcripts observed after T-cell activation was inhibited by IL-10. IL-10 also inhibited the increase in collagenase and stromelysin-1 in the explant culture supernatants and the loss of glycosaminoglycans. IL-10 decreased metalloproteinase production in control explants and increased matrix. In mesenchymal cells, IL-10 had a minor effect on metalloproteinase production. CONCLUSIONS:IL-10 down-regulates mucosal T-cell activation, metalloproteinase production, and loss of extracellular matrix and prevents mucosal damage in the gut.
Authors: E Louis; C Ribbens; A Godon; D Franchimont; D De Groote; N Hardy; J Boniver; J Belaiche; M Malaise Journal: Clin Exp Immunol Date: 2000-05 Impact factor: 4.330
Authors: S Schreiber; P Rosenstiel; J Hampe; S Nikolaus; B Groessner; A Schottelius; T Kühbacher; J Hämling; U R Fölsch; D Seegert Journal: Gut Date: 2002-09 Impact factor: 23.059