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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
6
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pubmed:dateCreated |
1993-4-13
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pubmed:abstractText |
The single cell-thick intestinal epithelium forms a crucial barrier between the host and environment, and is modeled in vitro by a monolayer of polarized, highly differentiated T84 epithelial cells impermeable to most macromolecules because of functional intercellular tight junctions. Absence of a permeability defect across the monolayer, either transcellular or paracellular, is indicated by development of a transepithelial electrical resistance of > or = 1000 ohm-cm2, reported to be markedly diminished by exposure to a T lymphocyte cytokine, IFN-gamma. We sought to define this phenomenon in four ways by determining its duration and reversibility; the uniqueness of type II (gamma) IFN as opposed to type I (alpha) IFN; the surface of the polarized columnar epithelium likely involved in responding to IFN-gamma; and whether a specific surface membrane receptor on the epithelial cell participates in the response. Using a special apparatus that allows differential cytokine exposure of monolayer surfaces, our data demonstrate 1) only the monolayer's basolateral surface is IFN-gamma responsive, whereas the apical (microvillous) surface is no; 2) the alteration in electrical resistance of epithelium is prolonged (5 days), even after a single (24 h) exposure to IFN-gamma, but nevertheless is reversible; 3) the effect is likely receptor-ligand mediated, because it can be partially blocked by IFN-gamma receptor-specific monoclonal Ig; 4) an alteration in tight junction function (a paracellular pathway) rather than cell necrosis or a transcellular pathway is responsible for IFN-gamma-induced monolayer dysfunction because permeability to a 44,000-Da macromolecule (horseradish peroxidase) did not increase, and intracytoplasmic T84 cell enzymes were not released into the media; and 5) the biologic phenomenon could not be induced by a species (alpha) of class I IFN, making IFN-gamma reasonably unique in this regard. Given the proximity; activation status, and capacity of T lymphocytes for cytokine production in mucosa, we suggest that IFN-gamma-induced changes in epithelial permeability may be a major cause of altered intestinal barrier function in vivo.
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pubmed:grant | |
pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
AIM
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pubmed:chemical | |
pubmed:status |
MEDLINE
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pubmed:month |
Mar
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pubmed:issn |
0022-1767
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:day |
15
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pubmed:volume |
150
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
2356-63
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pubmed:dateRevised |
2008-11-21
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pubmed:meshHeading |
pubmed-meshheading:8450217-Antibodies, Monoclonal,
pubmed-meshheading:8450217-Binding, Competitive,
pubmed-meshheading:8450217-Binding Sites,
pubmed-meshheading:8450217-Cell Membrane Permeability,
pubmed-meshheading:8450217-Cells, Cultured,
pubmed-meshheading:8450217-Epithelial Cells,
pubmed-meshheading:8450217-Epithelium,
pubmed-meshheading:8450217-Humans,
pubmed-meshheading:8450217-Interferon-gamma,
pubmed-meshheading:8450217-Intestinal Mucosa,
pubmed-meshheading:8450217-Necrosis,
pubmed-meshheading:8450217-Protein Binding,
pubmed-meshheading:8450217-Receptors, Interferon,
pubmed-meshheading:8450217-Time Factors
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pubmed:year |
1993
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pubmed:articleTitle |
IFN-gamma modulation of epithelial barrier function. Time course, reversibility, and site of cytokine binding.
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pubmed:affiliation |
Department of Surgery, University of Virginia Health Sciences Center, Charlottesville 22908.
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pubmed:publicationType |
Journal Article,
Research Support, U.S. Gov't, P.H.S.
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