scholarly journals Salmonella entericaserovar Typhimurium regulates intercellular junction proteins and facilitates transepithelial neutrophil and bacterial passage

2007 ◽  
Vol 293 (1) ◽  
pp. G178-G187 ◽  
Author(s):  
Henrik Köhler ◽  
Takanori Sakaguchi ◽  
Bryan P. Hurley ◽  
Benjamin J. Kase ◽  
Hans-Christian Reinecker ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Bacterial Translocation ◽  
Intestinal Epithelium ◽  
Intestinal Barrier ◽  
Fold Increase ◽  
Molecular Composition ◽  
Junctional Complex ◽  
Intestinal Epithelial ◽  
Serovar Typhimurium ◽  
Triton X

The establishment of tight junctions (TJ) between columnar epithelial cells defines the functional barrier, which enteroinvasive pathogens have to overcome. Salmonella enterica serovar Typhimurium ( S. typhimurium) directly invades intestinal epithelial cells but it is not well understood how the pathogen is able to overcome the intestinal barrier and gains access to the circulation. Therefore, we sought to determine whether infection with S. typhimurium could regulate the molecular composition of the TJ and, if so, whether these modifications would influence bacterial translocation and polymorphonuclear leukocyte (PMN) movement across model intestinal epithelium. We found that infection of a model intestinal epithelium with S. typhimurium over 2 h resulted in an ∼80% loss of transepithelial electrical resistance. Western blot analysis of epithelial cell lysates demonstrated that S. typhimurium regulated the distribution of the TJ complex proteins claudin-1, zonula occludens (ZO)-2, and E-cadherin in Triton X-100-soluble and insoluble fractions. In addition, S. typhimurium was specifically able to dephosphorylate occludin and degrade ZO-1. This TJ alteration in the epithelial monolayer resulted in 10-fold increase in bacterial translocation and a 75% increase in N-formylmethionin-leucyl-phenyalanine-induced PMN transepithelial migration. Our data demonstrate that infection with S. typhimurium is associated with the rapid targeting of the tight junctional complex and loss of barrier function. This results in enhanced bacterial translocation and initiation of PMN migration across the intestinal barrier. Therefore, the ability to regulate the molecular composition of TJs facilitates the pathogenicity of S. typhimurium by aiding its uptake and distribution within the host.

scholarly journals A Micro-engineered Human Colon Intestine-Chip Platform to Study Leaky Barrier

2020 ◽  
Author(s):  
Athanasia Apostolou ◽  
Rohit A. Panchakshari ◽  
Antara Banerjee ◽  
Dimitris V. Manatakis ◽  
Maria D. Paraskevopoulou ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Intestinal Epithelium ◽  
Unmet Need ◽  
Intestinal Barrier ◽  
Human Colon ◽  
Epithelial Barrier ◽  
Host Immune System ◽  
Intestinal Epithelial ◽  
Barrier Disruption ◽  
Interleukin 22

ABSTRACTThe intestinal epithelial barrier supports the symbiotic relationship between the microbiota colonizing the intestinal epithelium and the host immune system to maintain homeostasis. Leaky barrier is increasingly recognized as part of the pathogenesis of a number of chronic conditions in addition to inflammatory and infectious diseases. As our understanding on the regulation of the barrier remains limited, effective therapeutic targeting for the compromised barrier is still an unmet need. Here we combined advancements on the organoids and Organ-on-Chip technologies to establish a micro-engineered Colon Intestine-Chip for studying development and regulation of the human intestinal barrier. Our data demonstrate the significance of the endothelium in co-culture with the epithelial cells within a tissue-relevant microenvironment for the establishment of a tight epithelial barrier of polarized cells. Pathway analysis of the RNA sequencing (RNA-Seq), revealed significant upregulation of mechanisms relevant to the maturation of the intestinal epithelium in organoid-derived epithelial cells in co-culture with endothelium as compared to organoids maintained in suspension. We provide evidence that the Colon Intestine-Chip platform responds to interferon gamma (IFNγ), a prototype cytokine utilized to model inflammation-induced barrier disruption, by induction of apoptosis and reorganization of the apical junctional complexes as shown with other systems. We also describe the mechanism of action of interleukin 22 (IL-22) on mature, organoid-derived intestinal epithelial cells that is consistent with barrier disruption. Overall we propose the Colon Intestine-Chip as a promising human organoid-derived platform to decipher mechanisms driving the development of leaky gut in patients and enable their translation for this unmet medical need.

scholarly journals Epithelial Cells Augment Barrier Function via Activation of the Toll-Like Receptor 2/Phosphatidylinositol 3-Kinase Pathway upon Recognition of Salmonella enterica Serovar Typhimurium Curli Fibrils in the Gut

2012 ◽  
Vol 81 (2) ◽  
pp. 478-486 ◽  
Author(s):  
Gertrude O. Oppong ◽  
Glenn J. Rapsinski ◽  
Tiffanny N. Newman ◽  
Jessalyn H. Nishimori ◽  
Steven G. Biesecker ◽  
...  
Keyword(s):  
Bacterial Translocation ◽  
Intestinal Epithelium ◽  
Salmonella Enterica ◽  
Intestinal Epithelial ◽  
Toll Like Receptor ◽  
Wild Type ◽  
Phosphatidylinositol 3 Kinase ◽  
Serovar Typhimurium ◽  
Toll Like Receptor 2 ◽  
Phosphatidylinositol 3

ABSTRACTCurli fibrils, the best-characterized functional bacterial amyloids, are an important component of enterobacterial biofilms. We have previously shown that curli fibrils are recognized by the Toll-like receptor 2 (TLR2)/TLR1 heterodimer complex. Utilizing polarized T-84 cells, an intestinal epithelial cell line derived from colon carcinoma grown on semipermeable tissue culture inserts, we determined that infection with aSalmonella entericaserovar TyphimuriumcsgBAmutant, which does not express curli, resulted in an increase in intestinal barrier permeability and an increase in bacterial translocation compared to infection with curliated wild-typeS. Typhimurium. When the TLR2 downstream signaling molecule phosphatidylinositol 3-kinase (PI3K) was blocked using wortmannin or LY294002, the difference in disruption of the intestinal epithelium and bacterial translocation was no longer observed. Additionally, disruption of polarized T-84 cells treated basolaterally with the TLR5 ligand flagellin was prevented when the polarized cells were simultaneously treated with the synthetic TLR2/TLR1 ligand Pam3CSK4or with purified curli fibrils in the apical compartment. Similar toin vitroobservations, C57BL/6 mice infected with thecsgBAmutant suffered increased disruption of the intestinal epithelium and therefore greater dissemination of the bacteria to the mesenteric lymph nodes than mice infected with wild-typeS. Typhimurium. The differences in disruption of the intestinal epithelium and bacterial dissemination in the mice infected withcsgBAmutant or wild-typeS. Typhimurium were not apparent in TLR2-deficient mice. Overall, these studies report for the first time that activation of the TLR2/PI3K pathway by microbial amyloids plays a critical role in regulating the intestinal epithelial barrier as well as monitoring bacterial translocation during infection.

scholarly journals A novel two-compartment barrier model for investigating nanoparticle transport in fish intestinal epithelial cells

2016 ◽  
Vol 3 (2) ◽  
pp. 388-395 ◽  
Author(s):  
Mark Geppert ◽  
Laura Sigg ◽  
Kristin Schirmer
Keyword(s):  
Rainbow Trout ◽  
Epithelial Cells ◽  
Intestinal Epithelium ◽  
Intestinal Epithelial Cells ◽  
Intestinal Barrier ◽  
Intestinal Epithelial ◽  
Nanoparticle Transport ◽  
Barrier Model

We introduce a novel in vitro rainbow trout intestinal barrier model and demonstrate its suitability for investigating nanoparticle transport across the intestinal epithelium.

scholarly journals The mRNA-binding protein IGF2BP1 maintains intestinal barrier function by up-regulating occludin expression

2020 ◽  
Vol 295 (25) ◽  
pp. 8602-8612
Author(s):  
Vikash Singh ◽  
Chethana P. Gowda ◽  
Vishal Singh ◽  
Ashwinkumar S. Ganapathy ◽  
Dipti M. Karamchandani ◽  
...  
Keyword(s):  
Intestinal Epithelium ◽  
Barrier Function ◽  
Binding Protein ◽  
Intestinal Barrier ◽  
Intestinal Barrier Function ◽  
Intestinal Epithelial ◽  
Adult Mice ◽  
Junction Protein ◽  
Mrna Binding Protein ◽  
Mrna Binding

Insulin-like growth factor 2 mRNA-binding protein 1 (IGF2BP1) is an mRNA-binding protein that has an oncofetal pattern of expression. It is also expressed in intestinal tissue, suggesting that it has a possible role in intestinal homeostasis. To investigate this possibility, here we generated Villin CreERT2:Igf2bp1flox/flox mice, which enabled induction of an IGF2BP1 knockout specifically in intestinal epithelial cells (IECs) of adult mice. Using gut barrier and epithelial permeability assays and several biochemical approaches, we found that IGF2BP1 ablation in the adult intestinal epithelium causes mild active colitis and mild-to-moderate active enteritis. Moreover, the IGF2BP1 deletion aggravated dextran sodium sulfate–induced colitis. We also found that IGF2BP1 removal compromises barrier function of the intestinal epithelium, resulting from altered protein expression at tight junctions. Mechanistically, IGF2BP1 interacted with the mRNA of the tight-junction protein occludin (Ocln), stabilizing Ocln mRNA and inducing expression of occludin in IECs. Furthermore, ectopic occludin expression in IGF2BP1-knockdown cells restored barrier function. We conclude that IGF2BP1-dependent regulation of occludin expression is an important mechanism in intestinal barrier function maintenance and in the prevention of colitis.

scholarly journals PTPN2 Regulates Interactions Between Macrophages and Intestinal Epithelial Cells to Promote Intestinal Barrier Function

2020 ◽  
Vol 159 (5) ◽  
pp. 1763-1777.e14 ◽  
Author(s):  
Marianne R. Spalinger ◽  
Anica Sayoc-Becerra ◽  
Alina N. Santos ◽  
Ali Shawki ◽  
Vinicius Canale ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Barrier Function ◽  
Intestinal Epithelial Cells ◽  
Intestinal Barrier ◽  
Intestinal Barrier Function ◽  
Intestinal Epithelial

OmpD but not OmpC is involved in adherence ofSalmonella entericaserovar Typhimurium to human cells

2004 ◽  
Vol 50 (9) ◽  
pp. 719-727 ◽  
Author(s):  
Bochiwe Hara-Kaonga ◽  
Thomas G Pistole
Keyword(s):  
Epithelial Cells ◽  
Intestinal Epithelial Cells ◽  
Human Cells ◽  
Host Cells ◽  
Intestinal Epithelial ◽  
Wild Type ◽  
Human Macrophages ◽  
Significant Difference ◽  
Serovar Typhimurium

Conflicting reports exist regarding the role of porins OmpC and OmpD in infections due to Salmonella enterica serovar Typhimurium. This study investigated the role of these porins in bacterial adherence to human macrophages and intestinal epithelial cells. ompC and ompD mutant strains were created by transposon mutagenesis using P22-mediated transduction of Tn10 and Tn5 insertions, respectively, into wild-type strain 14028. Fluorescein-labeled wild-type and mutant bacteria were incubated with host cells at various bacteria to cell ratios for 1 h at 37 °C and analyzed by flow cytometry. The mean fluorescence intensity of cells with associated wild-type and mutant bacteria was used to estimate the number of bacteria bound per host cell. Adherence was also measured by fluorescence microscopy. Neither assay showed a significant difference in binding of the ompC mutant and wild-type strains to the human cells. In contrast, the ompD mutant exhibited lowered binding to both cell types. Our findings suggest that OmpD but not OmpC is involved in the recognition of Salmonella serovar Typhimurium by human macrophages and intestinal epithelial cells.Key words: Salmonella, adherence, porins, intestinal epithelial cells, macrophage.

Potassium Channels in Intestinal Epithelial Cells and their Pharmacological Modulation: A Systematic Review

2020 ◽  
Author(s):  
Dina Cosme ◽  
Maria Manuela Estevinho ◽  
Florian Rieder ◽  
Fernando Magro
Keyword(s):  
Epithelial Cells ◽  
Potassium Channels ◽  
Intestinal Epithelial Cells ◽  
Strong Association ◽  
Physiological Role ◽  
Intestinal Barrier ◽  
Intestinal Barrier Function ◽  
Intestinal Epithelial ◽  
Pharmacological Modulation ◽  
Inflammatory Bowel

Background: Several potassium channels (KCs) have been described throughout the gastrointestinal tract. Notwithstanding, their contribution to both physiologic and pathophysiologic conditions, as inflammatory bowel disease (IBD), remains underexplored. Therefore, we aim to systematically review, for the first time, the evidence on the characteristics and modulation of KCs in intestinal epithelial cells (IECs). Methods: PubMed, Scopus and Web of Science were searched to identify studies focusing on KCs and their modulation in IECs. The included studies were assessed using a reporting inclusiveness checklist. Results: From the 745 identified records, 73 met the inclusion criteria; their reporting inclusiveness was moderate-high. Some studies described the physiological role of KCs, while others explored their importance in pathological settings. Globally, in IBD animal models, apical KCa1.1 channels, responsible for luminal secretion, were upregulated. In human colonocytes, basolateral KCa3.1 channels were downregulated. The pharmacological inhibition of K2P and Kv influenced intestinal barrier function, promoting inflammation. Conclusion: Evidence suggests a strong association between KCs expression and secretory mechanisms in human and animal IECs. Further research is warranted to explore the usefulness of KC pharmacological modulation as a therapeutic target.

Sign in / Sign up

Export Citation Format

Share Document