Publications by authors named "Ulrike Lodemann"

Intestinal epithelial cells (IEC) and immune cells, such as dendritic cells (DC), jointly control the immune response towards luminal pathogens in the intestinal mucosa. Crosstalk between IEC and DC is crucial for coordinating immune responses and occurs via soluble factors and direct cell-cell contacts. The present study aimed at establishing a direct-contact co-culture model of porcine IEC and DC to mimic these interactions.

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The gut epithelium constitutes an interface between the intestinal contents and the underlying gut-associated lymphoid tissue (GALT) including dendritic cells (DC). Interactions of intestinal epithelial cells (IEC) and resident DC are characterized by bidirectional crosstalk mediated by various factors, such as transforming growth factor- (TGF-) and thymic stromal lymphopoietin (TSLP). In the present study, we aimed (1) to model the interplay of both cell types in a porcine coculture consisting of IEC (cell line IPEC-J2) and monocyte-derived DC (MoDC) and (2) to assess whether immune responses to bacteria are altered because of the interplay between IPEC-J2 cells and MoDC.

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Dendritic cells (DC) are crucial for maintaining intestinal homeostasis and generating proper immune responses to bacteria occurring in the gut. Microbial stimuli can be recognized by intracellular receptors called inflammasomes, e.g.

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The aim of the present study was to investigate systematically the expression of inflammasome components in pig intestine and to analyze the influence of age and long-term supplementation with the probiotic Enterococcus faecium NCIMB 10415 (E. faecium). In order to examine probiotic effects on the inflammasomes during a challenge with pathogens, enterotoxigenic Escherichia coli (ETEC) and E.

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The aim of the present study was to elucidate the effects of the probiotic feed additive NCIMB 10415 () on porcine jejunal epithelial cells (IPEC-J2) during an in vitro challenge with enterotoxigenic (ETEC). Cells were incubated with , ETEC, or both, and the effects on barrier function and structure and intra- and intercellular signaling were determined. Coincubation with abolished the ETEC-induced decrease in transepithelial resistance () ( ≤ 0.

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Background And Aim: Enterotoxigenic Escherichia coli (ETEC) strains are involved in piglet post-weaning diarrhea. Prophylactic measures including probiotics have been examined in infection experiments with live piglets. In the present study, we have tested whether the early effects of ETEC infection can also be evoked and studied in a model in which ETEC is added to whole mucosal tissues ex vivo, and whether this response can be modulated by prior supplementation of the piglets with probiotics.

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Probiotics have shown positive effects on gastrointestinal diseases; they have barrier-modulating effects and change the inflammatory response towards pathogens in studies in vitro. The aim of this investigation has been to examine the response of intestinal epithelial cells to Enterococcus faecium NCIMB 10415 (E. faecium), a probiotic positively affecting diarrhea incidence in piglets, and two pathogenic Escherichia coli (E.

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Zinc supplementation is used to reduce diarrhea incidence in piglets and it has been shown in vitro that the antisecretory effects are maximal after basolateral zinc application. To examine whether the application site and dose of zinc also influence passive ion permeability and viability, porcine (IPEC-J2) and human (Caco-2) intestinal epithelial cells were treated with increasing zinc concentrations (0-200 μM) at either the apical or basolateral side. Transepithelial electrical resistance and viability decreased and expression of metallothionein and the efflux zinc transporter 1 increased most prominently when zinc was added in high concentrations at the basolateral side of IPEC-J2 cells.

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The aim of this study has been to elucidate the effect of the probiotic Enterococcus faecium NCIMB 10415 on epithelial integrity in intestinal epithelial cells and whether pre- and coincubation with this strain can reproducibly prevent damage induced by enterotoxigenic (ETEC) and enteropathogenic Escherichia coli (EPEC). Porcine (IPEC-J2) and human (Caco-2) intestinal epithelial cells were incubated with bacterial strains and epithelial integrity was assessed by measuring transepithelial electrical resistance (TEER) and mannitol flux rates. E.

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After weaning, piglets are often fed diets supplemented with high concentrations of zinc (Zn) to decrease post-weaning diarrhea. The aim of this study was to elucidate the regulation of Zn homeostasis within intestinal epithelial cells during excessive Zn exposure. High Zn concentrations elevated the intracellular Zn level in IPEC-J2 and Caco-2 cells which was influenced by differentiation status and time of exposure.

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In vitro testing can contribute to reduce the risk that the use of genetically modified (GM) crops and their proteins show unintended toxic effects. Here we introduce a porcine intestinal cell culture (IPEC-J2) as appropriate in vitro model and tested the possible toxic potential of Cry1Ab protein, commonly expressed in GM-maize. For comprehensive risk assessment we used WST-1 conversion and ATP content as metabolic markers for proliferation, lactate dehydrogenase release as indicator for cells with compromised membrane and transepithelial electrical resistance as parameter indicating membrane barrier function.

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High dietary zinc concentrations are used to prevent or treat diarrhea in piglets and humans, but long-term adaptation to high zinc supply has yet not been assessed. Intestinal zinc uptake is facilitated through members of zinc transporter families SLC30 (ZnT) and SLC39 (ZIP). Whereas in rodents, regulation of zinc homeostasis at low or adequate zinc supply has been described, such mechanisms are unclear in piglets.

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The objective of the study was to assess the effects of feed supplementation with the probiotic Bacillus cereus var. toyoi on transport and barrier properties of pig jejunum. Sows and their respective piglets were randomly assigned to two feeding groups: a control group and a probiotic group in which the standard diet was supplemented with Bacillus cereus var.

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Many studies report positive effects of probiotic supplementation on the performance and health of piglets. The intention of this study was to describe the effects of Enterococcus faecium NCIMB 10415 on the transport and barrier functions of pig small intestine to improve our understanding of the underlying mechanisms of this probiotic. Ussing chamber studies were conducted with isolated jejunal epithelia of piglets at the age of 14, 28, 35 and 56 days.

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The intention of this study was to determine the effects of mucosal osmotic pressure on transport and barrier functions of the rumen epithelium of sheep, which were fed various diets: hay ad libitum, or 600, 1200 or 1800 g day(-1) of a supplemented diet plus hay ad libitum. The experiments were conducted by using the conventional Ussing chamber technique. Mucosal osmolarity was adjusted to 300 (control), 375 or 450 mosmol l(-1).

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In vitro studies on the pathogenesis in swine have been hampered by the lack of relevant porcine cell lines. Since many bacterial infections are swine-specific, studies on pathogenic mechanisms require appropriate cell lines of porcine origin. We have characterized the permanent porcine intestinal epithelial cell line, IPEC-J2, using a variety of methods in order to assess the usefulness of this cell line as an in vitro infection model.

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The effects of luminal hyperosmolarity on Na and Cl transport were studied in rumen epithelium of sheep. An increase of luminal osmotic pressure with mannitol (350 and 450 mosm/l) caused a significant increase of tissue conductance, G (T), which is linearly correlated with flux rates of (51)Cr-EDTA and indicates an increase of passive permeability. Studies with microelectrodes revealed, that an increase of the osmotic pressure caused a significant increase of the conductance of the shunt pathway from 1.

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