title: TFF3-peptide increases transepithelial resistance in epithelial cells by modulating claudin-1 and -2 expression.
abstract: TFF3 plays an important role in the protection and repair of the gastrointestinal mucosa. The molecular mechanisms of TFF function, however, are still largely unknown. Increasing evidence indicates that apart from stabilizing mucosal mucins TFF3 induces cellular signals that modulate cell-cell junctions of epithelia. In transfected HT29/B6 and MDCK cells stably expressing FLAG-tagged human TFF3 we have recently shown that TFF3 down-regulates E-cadherin, impairs the function of adherens junctions and thus facilitates cell migration in wounded epithelial cell layers. Here we investigate TFF3-induced effects on the composition and function of tight junctions in these cells. TFF3 increased the cellular level of tightening claudin-1 and decreased the amount of claudin-2 known to form cation-selective channels. Expression of ZO-1, ZO-2 and occludin was not altered. The change in claudin-1 and -2 expression in TFF3-expressing HT29/B6 cells was accompanied by an increase in the transepithelial resistance in confluent monolayers of these cells. These data suggest that TFF3 plays a role in the regulation of intestinal barrier function by altering the claudin composition within tight junctions thus decreasing paracellular permeability of the intestinal mucosa.
authors.affiliation: Department of Laboratory Medicine and Pathobiochemistry, Charité-Campus Benjamin Franklin, Hindenburgdamm 30, 12200 Berlin, Germany.
authors.forename: Dirk
authors.initials: D
authors.lastname: Meyer zum Büschenfelde
authors.forename: Rudolf
authors.initials: R
authors.lastname: Tauber
authors.forename: Otmar
authors.initials: O
authors.lastname: Huber
mesh_terms: D000818:Animals; D002460:Cell Line; D002463:Cell Membrane Permeability / Q000502:physiology*; D062445:Claudin-1; D057167:Claudins; D004285:Dogs; D004847:Epithelial Cells / Q000378:metabolism*; D019073:HT29 Cells; D006801:Humans; D007413:Intestinal Mucosa / Q000166:cytology / Q000378:metabolism; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D010455:Peptides / Q000235:genetics / Q000502:physiology*; D019108:Tight Junctions / Q000378:metabolism; D000071165:Trefoil Factor-3
chemical_list: C568108:CLDN1 protein, human; C491875:CLDN2 protein, human; D062445:Claudin-1; D057167:Claudins; D008565:Membrane Proteins; D010455:Peptides; C082495:TFF3 protein, human; D000071165:Trefoil Factor-3