scholarly journals Impact of vaginal douching products on vaginal Lactobacillus, Escherichia coli and epithelial immune responses

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Helai Hesham ◽  
Alissa J. Mitchell ◽  
Agnes Bergerat ◽  
Kristin Hung ◽  
Caroline M. Mitchell
Keyword(s):  
Escherichia Coli ◽  
Cell Death ◽  
Epithelial Cell ◽  
Epithelial Cells ◽  
Immune Responses ◽  
E Coli ◽  
Vaginal Douching ◽  
Vaginal Epithelial Cells ◽  
Epithelial Disruption ◽  
Epithelial Cell Death

AbstractWe compared the effect of commercial vaginal douching products on Lactobacillus crispatus, L. jensenii, L. gasseri, L. iners, E. coli, and immortalized vaginal epithelial cells (VK2). All studied douching products (vinegar, iodine and baking soda based) induced epithelial cell death, and all inhibited growth of E. coli. Co-culture of vaginal epithelial cells with any of the lactobacilli immediately following exposure to douching products resulted in a trend to less human cell death. However, co-culture of epithelial cells with L. iners was associated with higher production of IL6 and IL8, and lower IL1RA regardless of presence or type of douching solution. Co-culture with L. crispatus or L. jensenii decreased IL6 production in the absence of douches, but increased IL6 production after exposure to vinegar. Douching products may be associated with epithelial disruption and inflammation, and may reduce the anti-inflammatory effects of beneficial lactobacilli.

The role of 17β-estrogen in Escherichia coli adhesion on human vaginal epithelial cells via FAK phosphorylation

2021 ◽  
Author(s):  
Xia Liu ◽  
Ting Luan ◽  
Wanqing Zhou ◽  
Lina Yan ◽  
Hua Qian ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Epithelial Cell ◽  
Epithelial Cells ◽  
Specific Inhibitor ◽  
Estrogen Receptor Α ◽  
Epithelial Cell Line ◽  
Vaginal Epithelial Cell ◽  
E Coli ◽  
Vaginal Epithelial Cells

Estrogen, the predominant sex hormone, has been found to be related to the occurrence of vaginal infectious diseases. However, its role in the occurrence and development of bacterial vaginitis caused by Escherichia coli is still unclear. The objective of this study was to investigate the role of 17β-estrogen in E. coli adhesion on human vaginal epithelial cells. The vaginal epithelial cell line, VK2/E6E7, was used to study the molecular events induced by estrogen between E. coli and cells. An adhesion study was performed to evaluate the involvement of the estrogen-dependent focal adhesion kinase (FAK) activation with cell adhesion. The phosphorylation status of FAK and estrogen receptor α (ERα) upon estrogen challenge was assessed by Western blotting. Specific inhibitors for ERα were used to validate the involvement of ERα-FAK signaling cascade. The results showed that, following the stimulation with 1000 nM estrogen for 48 h, a transient activation of ERα and FAK was observed, as well as the increased average number of E. coli adhering to vaginal epithelial cell. In addition, estrogen-induced activation of ERa and FAK was inhibited by the specific inhibitor of ERα, especially when the inhibitor reached a 10 μM concentration and acted for 1 h, and a decrease in the number of adherent E. coli was observed simultaneously. However, this inhibitory effect diminished as the concentration of estrogen increased. In conclusion, FAK and ERα signaling cascades were assosiated with the increasing E. coli adherence to vaginal epithelial cells, which was promoted by a certain concentration of estrogen.

scholarly journals Interaction of an Outer Membrane Protein of Enterotoxigenic Escherichia coli with Cell Surface Heparan Sulfate Proteoglycans

2002 ◽  
Vol 70 (3) ◽  
pp. 1530-1537 ◽  
Author(s):  
James M. Fleckenstein ◽  
James T. Holland ◽  
David L. Hasty
Keyword(s):  
Escherichia Coli ◽  
Epithelial Cell ◽  
Epithelial Cells ◽  
Cell Surface ◽  
Heparan Sulfate ◽  
Heparan Sulfate Proteoglycans ◽  
Eukaryotic Cells ◽  
Heparin Binding ◽  
Wild Type ◽  
E Coli

ABSTRACT We have previously shown that enterotoxigenic invasion protein A (Tia), a 25-kDa outer membrane protein encoded on an apparent pathogenicity island of enterotoxigenic Escherichia coli (ETEC) strain H10407, mediates attachment to and invasion into cultured human gastrointestinal epithelial cells. The epithelial cell receptor(s) for Tia has not been identified. Here we show that Tia interacts with cell surface heparan sulfate proteoglycans. Recombinant E. coli expressing Tia mediated invasion into wild-type epithelial cell lines but not invasion into proteoglycan-deficient cells. Furthermore, wild-type eukaryotic cells, but not proteoglycan-deficient eukaryotic cells, attached to immobilized polyhistidine-tagged recombinant Tia (rTia). Binding of epithelial cells to immobilized rTia was inhibited by exogenous heparan sulfate glycosaminoglycans but not by hyaluronic acid, dermatan sulfate, or chondroitin sulfate. Similarly, pretreatment of eukaryotic cells with heparinase I, but not pretreatment of eukaryotic cells with chrondroitinase ABC, inhibited attachment to rTia. In addition, we also observed heparin binding to both immobilized rTia and recombinant E. coli expressing Tia. Heparin binding was inhibited by a synthetic peptide representing a surface loop of Tia, as well as by antibodies directed against this peptide. Additional studies indicated that Tia, as a prokaryotic heparin binding protein, may also interact via sulfated proteoglycan molecular bridges with a number of mammalian heparan sulfate binding proteins. These findings suggest that the binding of Tia to host epithelial cells is mediated at least in part through heparan sulfate proteoglycans and that ETEC belongs on the growing list of pathogens that utilize these ubiquitous cell surface molecules as receptors.

Protective effect of IL-6 on alveolar epithelial cell death induced by hydrogen peroxide

2005 ◽  
Vol 288 (2) ◽  
pp. L342-L349 ◽  
Author(s):  
Hiroshi Kida ◽  
Mitsuhiro Yoshida ◽  
Shigenori Hoshino ◽  
Koji Inoue ◽  
Yukihiro Yano ◽  
...  
Keyword(s):  
Gene Expression ◽  
Cell Death ◽  
Epithelial Cell ◽  
Epithelial Cells ◽  
Alveolar Epithelial Cell ◽  
Alveolar Epithelial Cells ◽  
Lung Fibroblasts ◽  
Alveolar Epithelial ◽  
Epithelial Cell Death

The goal of this study was to examine whether IL-6 could directly protect lung resident cells, especially alveolar epithelial cells, from reactive oxygen species (ROS)-induced cell death. ROS induced IL-6 gene expression in organotypic lung slices of wild-type (WT) mice. ROS also induced IL-6 gene expression in mouse primary lung fibroblasts, dose dependently. The organotypic lung slices of WT were more resistant to ROS-induced DNA fragmentation than those of IL-6-deficient (IL-6−/−) mice. WT resistance against ROS was abrogated by treatment with anti-IL-6 antibody. TdT-mediated dUTP nick end labeling stain and electron microscopy revealed that DNA fragmented cells in the IL-6−/− slice included alveolar epithelial cells and endothelial cells. In vitro studies demonstrated that IL-6 reduced ROS-induced A549 alveolar epithelial cell death. Together, these data suggest that IL-6 played an antioxidant role in the lung by protecting lung resident cells, especially alveolar epithelial cells, from ROS-induced cell death.

scholarly journals Synthetic bottom-up approach reveals the complex interplay ofShigellaeffectors in regulation of epithelial cell death

2018 ◽  
Vol 115 (25) ◽  
pp. 6452-6457 ◽  
Author(s):  
Xiangyu Mou ◽  
Skye Souter ◽  
Juan Du ◽  
Analise Z. Reeves ◽  
Cammie F. Lesser
Keyword(s):  
Cell Death ◽  
Epithelial Cell ◽  
Epithelial Cells ◽  
Host Cells ◽  
Bottom Up ◽  
Type Iii Effectors ◽  
Type Iii ◽  
Bacterial Replication ◽  
Almost All ◽  
Epithelial Cell Death

Over the course of an infection, many Gram-negative bacterial pathogens use complex nanomachines to directly inject tens to hundreds of proteins (effectors) into the cytosol of infected host cells. These effectors rewire processes to promote bacterial replication and spread. The roles of effectors in pathogenesis have traditionally been investigated by screening for phenotypes associated with their absence, a top-down approach that can be limited, as effectors often act in a functionally redundant or additive manner. Here we describe a syntheticEscherichia coli-based bottom-up platform to conduct gain-of-function screens for roles of individualShigellaeffectors in pathogenesis. As proof of concept, we screened forShigellaeffectors that limit cell death induced on cytosolic entry of bacteria into epithelial cells. Using this platform, in addition to OspC3, an effector known to inhibit cell death via pyroptosis, we have identified OspD2 and IpaH1.4 as cell death inhibitors. In contrast to almost all type III effectors, OspD2 does not target a host cell process, but rather regulates the activity of theShigellatype III secretion apparatus limiting the cytosolic delivery (translocation) of effectors during an infection. Remarkably, by limiting the translocation of a single effector, VirA, OspD2 controls the timing of epithelial cell death via calpain-mediated necrosis. Together, these studies provide insight into the intricate manner by whichShigellaeffectors interact to establish a productive intracytoplasmic replication niche before the death of infected epithelial cells.

scholarly journals Candida albicans infection disturbs the redox homeostasis system and induces reactive oxygen species accumulation for epithelial cell death

2019 ◽  
Vol 20 (4) ◽  
Author(s):  
Tongtong Ren ◽  
Hangqi Zhu ◽  
Lei Tian ◽  
Qilin Yu ◽  
Mingchun Li
Keyword(s):  
Reactive Oxygen Species ◽  
Cell Death ◽  
Candida Albicans ◽  
Epithelial Cell ◽  
Epithelial Cells ◽  
Tissue Damage ◽  
Redox Homeostasis ◽  
Oxygen Species ◽  
Ros Accumulation ◽  
Epithelial Cell Death

ABSTRACT Candida albicans is a common pathogenic fungus with high mortality in immunocompromised patients. However, the mechanism by which C. albicans invades host epithelial cells and causes serious tissue damage remains to be further investigated. In this study, we established the C. albicans–293T renal epithelial cell interaction model to investigate the mechanism of epithelial infection by this pathogen. It was found that C. albicans infection causes severe cell death and reactive oxygen species (ROS) accumulation in epithelial cells. Further investigations revealed that C. albicans infection might up-regulate expression of nicotinamide adenine dinucleotide phosphate (NAPDH) oxidase (NOX), inhibit the activity of the antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT), and suppress the p38–Nrf2–heme oxygenase-1 (HO-1) pathway which plays an important role in the elimination of intracellular ROS. Furthermore, epithelial cell death caused by the fungal infection could be strikingly alleviated by addition of the antioxidant agent glutathione, indicating the critical role of ROS accumulation in cell death caused by the fungus. This study revealed that disturbance of the redox homeostasis system and ROS accumulation in epithelial cells is involved in cell death caused by C. albicans infection, which sheds light on the application of antioxidants in the suppression of tissue damage caused by fungal infection.

scholarly journals CD14- and Toll-Like Receptor-Dependent Activation of Bladder Epithelial Cells by Lipopolysaccharide and Type 1 Piliated Escherichia coli

2003 ◽  
Vol 71 (3) ◽  
pp. 1470-1480 ◽  
Author(s):  
Joel D. Schilling ◽  
Steven M. Martin ◽  
David A. Hunstad ◽  
Kunal P. Patel ◽  
Matthew A. Mulvey ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Epithelial Cell ◽  
Epithelial Cells ◽  
Cell Lines ◽  
Epithelial Cell Line ◽  
Renal Epithelial Cell ◽  
E Coli ◽  
Epithelial Cell Lines ◽  
Renal Epithelial Cell Line

ABSTRACT The gram-negative bacterium Escherichia coli is the leading cause of urinary tract infection. The interaction between type 1 piliated E. coli and bladder epithelial cells leads to the rapid production of inflammatory mediators, such as interleukin-6 (IL-6) and IL-8. Conflicting reports have been published in the literature regarding the mechanism by which uroepithelial cells are activated by type 1 piliated E. coli. In particular, the role of lipopolysaccharide (LPS) in these responses has been an area of significant debate. Much of the data arguing against LPS-mediated activation of bladder epithelial cells have come from studies using a renal epithelial cell line as an in vitro model of the urinary epithelium. In this report, we analyzed three bladder epithelial cell lines and demonstrated that they all respond to LPS. Furthermore, the LPS responsivity of the cell lines directly correlated with their ability to generate IL-6 after E. coli stimulation. The LPS receptor complex utilized by the bladder epithelial cell lines included CD14 and Toll-like receptors, and signaling involved the activation of NF-κB and p38 mitogen-activated protein kinase. Also, reverse transcription-PCR analysis demonstrated that bladder epithelial cells express CD14 mRNA. Thus, the molecular machinery utilized by bladder epithelial cells for the recognition of E. coli is very similar to that described for traditional innate immune cells, such as macrophages. In contrast, the A498 renal epithelial cell line did not express CD14, was hyporesponsive to LPS stimulation, and demonstrated poor IL-6 responses to E. coli.

scholarly journals Shiga Toxin 2e-Producing Escherichia coli Isolates from Humans and Pigs Differ in Their Virulence Profiles and Interactions with Intestinal Epithelial Cells

2005 ◽  
Vol 71 (12) ◽  
pp. 8855-8863 ◽  
Author(s):  
Anne-Katharina Sonntag ◽  
Martina Bielaszewska ◽  
Alexander Mellmann ◽  
Nadine Dierksen ◽  
Peter Schierack ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Epithelial Cell ◽  
Epithelial Cells ◽  
Shiga Toxin ◽  
Intestinal Epithelial Cell ◽  
Intestinal Epithelial Cells ◽  
Epithelial Cell Line ◽  
Uptake System ◽  
Intestinal Epithelial ◽  
E Coli

ABSTRACT Thirteen Escherichia coli strains harboring stx 2e were isolated from 11,056 human stools. This frequency corresponded to the presence of the stx 2e allele in 1.7% of all Shiga toxin-producing E. coli (STEC) strains. The strains harboring stx 2e were associated with mild diarrhea (n = 9) or asymptomatic infections (n= 4). Because STEC isolates possessing stx 2e are porcine pathogens, we compared the human STEC isolates with stx 2e-harboring E. coli isolated from piglets with edema disease and postweaning diarrhea. All pig isolates possessed the gene encoding the F18 adhesin, and the majority possessed adhesin involved in diffuse adherence; these adhesins were absent from all the human STEC isolates. In contrast, the high-pathogenicity island encoding an iron uptake system was found only in human isolates. Host-specific patterns of interaction with intestinal epithelial cells were observed. All human isolates adhered to human intestinal epithelial cell lines T84 and HCT-8 but not to pig intestinal epithelial cell line IPEC-J2. In contrast, the pig isolates completely lysed human epithelial cells but not IPEC-J2 cells, to which most of them adhered. Our data demonstrate that E. coli isolates producing Shiga toxin 2e have imported specific virulence and fitness determinants which allow them to adapt to the specific hosts in which they cause various forms of disease.

scholarly journals Enterotoxigenic Escherichia coli TibA Glycoprotein Adheres to Human Intestine Epithelial Cells

2001 ◽  
Vol 69 (1) ◽  
pp. 52-57 ◽  
Author(s):  
Christoph Lindenthal ◽  
Eric A. Elsinghorst
Keyword(s):  
Escherichia Coli ◽  
Epithelial Cell ◽  
Epithelial Cells ◽  
Sodium Dodecyl ◽  
Enterotoxigenic Escherichia Coli ◽  
Human Intestine ◽  
Glycoprotein Synthesis ◽  
E Coli ◽  
Etec Strain ◽  
Link Type

ABSTRACT Enterotoxigenic Escherichia coli (ETEC) is capable of invading epithelial cell lines derived from the human ileum and colon. Two separate invasion loci (tia and tib) that direct noninvasive E. coli strains to adhere to and invade cultured human intestine epithelial cells have previously been isolated from the classical ETEC strain H10407 . The tib locus directs the synthesis of TibA, a 104-kDa outer membrane glycoprotein. Synthesis of TibA is directly correlated with the adherence and invasion phenotypes of the tib locus, suggesting that this protein is an adhesin and invasin. Here we report the purification of TibA and characterization of its biological activity. TibA was purified by continuous-elution preparative sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Purified TibA was biotin labeled and then shown to bind to HCT8 human ileocecal epithelial cells in a specific and saturable manner. Unlabeled TibA competed with biotin-labeled TibA, suggesting the presence of a specific TibA receptor in HCT8 cells. These results show that TibA acts as an adhesin. Polyclonal anti-TibA antiserum inhibited invasion of ETEC strain H10407 and of recombinantE. coli bearing tib locus clones, suggesting that TibA also acts as an invasin. The ability of TibA to direct epithelial cell adhesion suggests a role for this protein in ETEC pathogenesis.

scholarly journals Epithelial Cell Adherence Mediated by the Enterotoxigenic Escherichia coli Tia Protein

2000 ◽  
Vol 68 (12) ◽  
pp. 6595-6601 ◽  
Author(s):  
Joseph G. Mammarappallil ◽  
Eric A. Elsinghorst
Keyword(s):  
Escherichia Coli ◽  
Epithelial Cell ◽  
Epithelial Cells ◽  
Outer Membrane ◽  
Cell Invasion ◽  
Outer Membrane Proteins ◽  
Sodium Dodecyl ◽  
Enterotoxigenic Escherichia Coli ◽  
E Coli ◽  
Epithelial Cell Invasion

ABSTRACT In vitro studies have shown that enterotoxigenic Escherichia coli (ETEC) strains are capable of invading cultured epithelial cells derived from the human ileum and colon. Two separate invasion loci (tia and tib) have previously been isolated from the classical ETEC strain H10407 . The tialocus has been shown to direct the synthesis of Tia, a 25-kDa outer membrane protein. Tia is sufficient to confer the adherence and invasion phenotypes on laboratory stains of E. coli, suggesting that this protein is an adhesin and invasin. Here we report the purification of Tia and characterize its biological activity. Tia was purified by electroelution of outer membrane proteins that had been separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Purified Tia was labeled with biotin and then shown to bind to HCT8 human ileocecal epithelial cells in a specific and saturable manner. Polyclonal anti-Tia antiserum blocked this binding. These results show that Tia acts as an adhesin. Polyclonal anti-Tia antiserum also inhibited invasion of recombinant E. coli bearingtia clones, indirectly suggesting that Tia may also act as an invasin. We predict Tia to contain eight transmembrane amphipathic β-sheets with four loops that are exposed on the surface of the bacterial cell. A peptide corresponding to 19 residues in one of the four predicted surface-exposed loops inhibits Tia-mediated epithelial cell invasion. Seeding HCT8 cells on wells coated with purified Tia reduced Tia-mediated epithelial cell invasion. Together, these results indicate that Tia is an invasin and adhesin that binds a specific receptor on HCT8 cells.

scholarly journals miR-185 mediates lung epithelial cell death after oxidative stress

2016 ◽  
Vol 310 (7) ◽  
pp. L700-L710 ◽  
Author(s):  
Duo Zhang ◽  
Heedoo Lee ◽  
Yong Cao ◽  
Charles S. Dela Cruz ◽  
Yang Jin
Keyword(s):  
Cell Death ◽  
Epithelial Cell ◽  
Epithelial Cells ◽  
Lung Epithelial Cells ◽  
Lung Epithelial Cell ◽  
Time Dependent ◽  
Dependent Manner ◽  
Lung Epithelial ◽  
Class Iia Hdacs ◽  
Epithelial Cell Death

Lung epithelial cell death is a prominent feature involved in the development of acute lung injury (ALI) and acute respiratory distress syndrome (ARDS). Hyperoxia-induced ALI is an established animal model mimicking human ARDS. Small noncoding RNAs such as microRNAs (miRNAs) have potent physiological and pathological functions involving multiple disease processes. Emerging interests focus on the potential of miRNAs to serve as novel therapeutic targets and diagnostic biomarkers. We found that hyperoxia highly induces miR-185 and its precursor in human lung epithelial cells in a time-dependent manner, and this observation is confirmed using mouse primary lung epithelial cells. The hyperoxia-induced miR-185 is mediated by reactive oxygen species. Furthermore, histone deacetylase 4 (HDAC4) locates in the promoter region of miR-185. We found that hyperoxia suppresses HDAC4 specifically in a time-dependent manner and subsequently affects histone deacetylation, resulting in an elevated miR-185 transcription. Using MC1586, an inhibitor of class IIa HDACs, we showed that inhibition of class IIa HDACs upregulates the expression of miR-185, mimicking the effects of hyperoxia. Functionally, miR-185 promotes hyperoxia-induced lung epithelial cell death through inducing DNA damage. We confirmed functional roles of miR-185 using both the loss- and gain-of-function approaches. Moreover, multiple 14-3-3δ pathway proteins are highly attenuated by miR-185 in the presence of hyperoxia. Taken together, hyperoxia-induced miR-185 in lung epithelial cells contributes to oxidative stress-associated epithelial cell death through enhanced DNA damage and modulation of 14-3-3δ pathways.

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