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Effect of zinc deficiency on neutrophil transmigration and junction proteins distribution in Caco-2 cells
No full textZinc deficiency induces membrane barrier damage and increases neutrophil transmigration in Caco-2 cells
No full textZinc may contribute to the host defense by maintaining the membrane barrier. In this study, we questioned whether zinc deficiency affects the membrane function and junctional structure of intestinal epithelial cells, causing increased neutrophil migration. We used the Caco-2 cell line grown in control (C), zinc-deficient, or zinc-replete medium until differentiation. Zinc deprivation induced a decrease of transepithelial electrical resistance and alterations to tight and adherens junctions, with delocalization of zonula occludens (ZO-1), occludin, beta-catenin, and E-cadherin. Disorganization of F-actin and beta-tubulin was also found in zinc deficiency. These changes were associated with a loss of the amounts of ZO-1, occluding, and beta-tubulin. In addition, zinc deficiency caused a dephosphorylation of occludin and hyperphosphorylation of beta-catenin and ZO-1. Disruption of membrane barrier integrity led to increased migration of neutrophils. In addition, zinc deficiency induced an increase in the secretion of interleukin-8, epithelial neutrophil activating peptide-78, and growth-regulated oncogene-alpha, alterations that were not found when culture medium was replete with zinc. These results provide new information on the critical role played by dietary zinc in the maintenance of membrane barrier integrity and in controlling inflammatory cell infiltration
Cytokine gene expression in intestine of rat during the postnatal developmental period: increased IL-1 expression at weaning.
No full textIn the present study we have investigate whether cytokines are constitutively and differently expressed in intestine during the differentiative processes that take place at weaning. We have analyzed the expression of IL-1 beta, IL-2, IL-4 and IFN gamma by polymerase chain reaction in Peyer's patches (PP) and in intestine deprived of PP (I-PP) of rats from 16 to 30 days of age. The results showed a constitutive and marked expression of the cytokines already before weaning, with the exception of IL-2 in PP and IFN gamma in I-PP. IL-beta was the only cytokine to show a different expression at various ages with an initial increase at 19 days and a further elevation at 21 days when intestinal epithelium passes through major differentiative stages, suggesting an involvement of this cytokine in intestinal development. We have also tested whether treatment of rats with the immunosuppressor cyclosporin A (CsA) could affect intestinal differentiation. The results showed that only some markers of differentiation were affected (proliferation of staminal crypt cells and length of crypts). This was probably due to a direct effect rather than an immunomediated effect of CsA, since treatment of three intestinal cell lines (Caco-2, HT-29, FRIC) with CsA indicated that this drug can exert a cytostatic activity on intestinal cells
Effetto della carenza di zinco sulle proteine di giunzione e del citoscheletro in cellule Caco-2 e sulla migrazione di neutrofili
No full textTrasmigration of neutrophils and distribution of junction proteins were affected by zinc deficiency in Caco-2 cells
No full textMigrazione di neutrofili e riarrangiamento delle proteine giunzionali in cellule Caco-2 in carenza di zinco
No full textEffect of zinc deficiency on neutrophil transmigration and junction proteins distribution in Caco-2
No full textAltered expression, localization, and phosphorylation of epithelial junctional proteins in celiac disease.
Full text linkWe aimed to study the expression and localization
of the molecular components of enterocyte junctions in
celiac disease together with the level of tyrosine
phosphorylation, a phenomenon known to affect their
cellular distribution and function, and to explore the
influence of proinflammatory cytokines. Duodenal
biopsy specimens from patients with celiac disease and
control subjects were used for immunoprecipitation,
immunoblotting, and immunolocalization by using
antioccludin, anti–zonula occludens (ZO)-1, anti–
E-cadherin, anti–β-catenin, and antiphosphotyrosine
antibodies. The same procedures were carried out on
filter-grown Caco-2 cells incubated in the absence or
presence of interferon γ and tumor necrosis factor α. In
active celiac disease, the absence of a phosphorylated
ZO-1 and the extensive phosphorylation of β-catenin
might be responsible for the absence of membranous
localization of occludin and E-cadherin, respectively.
The in vitro system showed an influence of the cytokines
on the assembly of these complexes that proved the
opposite to celiac samples as far as tight junctions were
concerned because the presence of a phosphorylated
ZO-1 enables occludin to localize in the membrane
Tissue transglutaminase-specific HLA-DQ2 restricted T cell clones from peripheral blood of patients with coeliac disease
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