Suppression of T cell-mediated injury in human gut by interleukin 10: role of matrix metalloproteinases.
OBJECTIVE
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.
Department of Paediatric Gastroenterology, St. Bartholomew's and the Royal London School of Medicine and Dentistry, London, England. s.pender@mds.qmw.ac.uk
S L
SL
Pender
E J
EJ
Breese
U
U
Günther
D
D
Howie
N C
NC
Wathen
D
D
Schuppan
T T
TT
MacDonald
D015703:Antigens, CD / Q000032:analysis; D017252:CD3 Complex / Q000032:analysis; D017364:Collagenases / Q000096:biosynthesis; D016207:Cytokines / Q000096:biosynthesis*; D004768:Enterotoxins / Q000633:toxicity; D005333:Fetus; D006025:Glycosaminoglycans / Q000378:metabolism; D006801:Humans; D018928:Immunity, Mucosal; D007371:Interferon-gamma / Q000096:biosynthesis / Q000235:genetics; D016753:Interleukin-10 / Q000494:pharmacology*; D007413:Intestinal Mucosa / Q000187:drug effects / Q000276:immunology* / Q000473:pathology; D007421:Intestine, Small / Q000187:drug effects / Q000378:metabolism* / Q000473:pathology; D007633:Keratins / Q000032:analysis; D008213:Lymphocyte Activation; D019278:Matrix Metalloproteinase 3 / Q000096:biosynthesis; D008648:Mesoderm / Q000187:drug effects / Q000201:enzymology / Q000473:pathology; D008666:Metalloendopeptidases / Q000096:biosynthesis* / Q000235:genetics; D009130:Muscle, Smooth / Q000196:embryology / Q000378:metabolism; D009924:Organ Culture Techniques; D011043:Pokeweed Mitogens; D016133:Polymerase Chain Reaction; D015375:Receptors, Interleukin-2 / Q000032:analysis; D013601:T-Lymphocytes / Q000276:immunology*; D014158:Transcription, Genetic
D015703:Antigens, CD; D017252:CD3 Complex; D016207:Cytokines; D004768:Enterotoxins; D006025:Glycosaminoglycans; D011043:Pokeweed Mitogens; D015375:Receptors, Interleukin-2; D016753:Interleukin-10; C031818:enterotoxin B, staphylococcal; D007633:Keratins; D007371:Interferon-gamma; D017364:Collagenases; D008666:Metalloendopeptidases; D019278:Matrix Metalloproteinase 3