scholarly journals Use of Defined Mutants To Assess the Role of theCampylobacter rectus S-Layer in Bacterium-Epithelial Cell Interactions

2000 ◽  
Vol 68 (3) ◽  
pp. 1465-1473 ◽  
Author(s):  
Beinan Wang ◽  
Ellen Kraig ◽  
David Kolodrubetz
Keyword(s):  
Epithelial Cell ◽  
Epithelial Cells ◽  
Proinflammatory Cytokines ◽  
Transforming Growth Factor ◽  
Periodontal Diseases ◽  
Enzyme Linked Immunosorbent Assay ◽  
Minor Effect ◽  
Mrna Levels ◽  
Tnf Α

ABSTRACT Campylobacter rectus is a periodontal pathogen with a 150-kDa protein on its cell surface. This protein forms a paracrystalline lattice, called the S-layer, surrounding the outer membrane of this gram-negative bacterium. To initiate a genetic analysis of the possible role of the S-layer in the initial interaction of C. rectus with host epithelial cells, C. rectus strains lacking the S-layer protein gene (crsA) were constructed by allelic exchange mutagenesis. Surprisingly, the lack of the S-layer had only a minor effect on the interaction of C. rectus with HEp-2 epithelial cells; CrsA+ cells were 30 to 50% more adherent than were CrsA− bacteria. Since the host cell expression of cytokines appears to play an important role in the pathogenesis of periodontal diseases, the effect of the S-layer on the epithelial cell cytokine response was also examined by quantitative reverse transcriptase PCR and enzyme-linked immunosorbent assay. Although there were no changes in the mRNA levels for the anti-inflammatory cytokines interleukin-1 receptor agonist (IL-1ra), IL-13, and transforming growth factor β, the expression and secretion of the proinflammatory cytokines IL-6, IL-8, and tumor necrosis factor alpha (TNF-α) were significantly induced by both wild-type C. rectus and CrsA− bacteria. Interestingly, the kinetics of cytokine induction differed for the CrsA+ and CrsA−bacteria. At early time points, the HEp-2 cells challenged with CrsA− bacteria produced higher levels of IL-6, IL-8, and TNF-α mRNA and protein than did cells challenged with CrsA+ bacteria. We conclude that C. rectus may help initiate periodontitis by increasing the expression of proinflammatory cytokines and that the S-layer may temper this response to facilitate the survival of C. rectus at the site of infection.

scholarly journals Production of Proinflammatory Cytokines and Inflammatory Mediators in Human Intestinal Epithelial Cells after Invasion by Trichinella spiralis

1998 ◽  
Vol 66 (5) ◽  
pp. 2200-2206 ◽  
Author(s):  
Chris K. F. Li ◽  
Rashmi Seth ◽  
Trevor Gray ◽  
Roger Bayston ◽  
Yashwant R. Mahida ◽  
...  
Keyword(s):  
Epithelial Cell ◽  
Epithelial Cells ◽  
Proinflammatory Cytokines ◽  
Inflammatory Mediators ◽  
Transforming Growth Factor ◽  
Trichinella Spiralis ◽  
Enzyme Linked Immunosorbent Assay ◽  
Bacterial Invasion ◽  
Inos Mrna ◽  
Intestinal Pathogens

ABSTRACT Epithelial cells are the first point of host contact for invasive intestinal pathogens and may initiate mucosal inflammatory responses via production of proinflammatory cytokines and mediators. The aim of the present study was to investigate in vitro the initial invasion of a parasitic nematode (Trichinella spiralis), to measure the early production of specific epithelial cytokines and inflammatory mediators after invasion, and to compare these responses with those to invasive bacteria. Monolayers of human colonic epithelial cell lines (HT29, T84, and Caco-2) were infected by T. spiralis orListeria monocytogenes. Bile-activated infective larvae ofT. spiralis invaded and migrated into the epithelial cell monolayers, leaving trails of dead cells. Transmission electron microscopy studies of damaged cells along the trail showed a progressive increase in size, disruption of cell membranes, loss or dilution of cytoplasmic proteins, and swelling of mitochondria and nuclei. However, no nuclear fragmentation was observed. With reverse transcription-PCR and an enzyme-linked oligonucleotide chemiluminescent assay, mRNA transcripts of interleukin-1β (IL-1β), IL-8, and epithelial neutrophil-activating peptide 78 were shown to increase in epithelial cells invaded by T. spiralis or L. monocytogenes, but only L. monocytogenes elicited increased inducible nitric oxide synthase (iNOS) mRNA. No increase in tumor necrosis factor alpha or transforming growth factor β mRNA was seen after T. spiralis invasion. Increased levels of IL-8 were also released from the basolateral surfaces of infected monolayers as detected by sandwich enzyme-linked immunosorbent assay. Induction and secretion of proinflammatory cytokines in epithelial cells after nematode or bacterial invasion may initiate the acute inflammatory response of the small intestine. The upregulation of iNOS in bacterial infections may contribute to mucosal defense and may also be associated with subsequent cell death, whereas different mechanisms appear to operate after nematode invasion.

scholarly journals Identification of a microRNA signature in renal fibrosis: role of miR-21

2011 ◽  
Vol 301 (4) ◽  
pp. F793-F801 ◽  
Author(s):  
Abolfazl Zarjou ◽  
Shanzhong Yang ◽  
Edward Abraham ◽  
Anupam Agarwal ◽  
Gang Liu
Keyword(s):  
Epithelial Cells ◽  
Renal Fibrosis ◽  
Transforming Growth Factor ◽  
Response To Treatment ◽  
Tubular Epithelial Cells ◽  
Altered Expression ◽  
Tnf Α ◽  
Tgf Β1

Renal fibrosis is a final stage of many forms of kidney disease and leads to impairment of kidney function. The molecular pathogenesis of renal fibrosis is currently not well-understood. microRNAs (miRNAs) are important players in initiation and progression of many pathologic processes including diabetes, cancer, and cardiovascular disease. However, the role of miRNAs in kidney injury and repair is not well-characterized. In the present study, we found a unique miRNA signature associated with unilateral ureteral obstruction (UUO)-induced renal fibrosis. We found altered expression in UUO kidneys of miRNAs that have been shown to be responsive to stimulation by transforming growth factor (TGF)-β1 or TNF-α. Among these miRNAs, miR-21 demonstrated the greatest increase in UUO kidneys. The enhanced expression of miR-21 was located mainly in distal tubular epithelial cells. miR-21 expression was upregulated in response to treatment with TGF-β1 or TNF-α in human renal tubular epithelial cells in vitro. Furthermore, we found that blocking miR-21 in vivo attenuated UUO-induced renal fibrosis, presumably through diminishing the expression of profibrotic proteins and reducing infiltration of inflammatory macrophages in UUO kidneys. Our data suggest that targeting specific miRNAs could be a novel therapeutic approach to treat renal fibrosis.

scholarly journals Increased Production of Proinflammatory Cytokines following Infection with Porcine Reproductive and Respiratory Syndrome Virus and Mycoplasma hyopneumoniae

2004 ◽  
Vol 11 (5) ◽  
pp. 901-908 ◽  
Author(s):  
Roongroje Thanawongnuwech ◽  
Brad Thacker ◽  
Patrick Halbur ◽  
Eileen L. Thacker
Keyword(s):  
Proinflammatory Cytokines ◽  
Mycoplasma Hyopneumoniae ◽  
Tracheal Ring ◽  
In Vivo Model ◽  
Respiratory Syndrome Virus ◽  
Enzyme Linked Immunosorbent Assay ◽  
Mrna Levels ◽  
Tnf Α

ABSTRACT Induction of the proinflammatory cytokines interleukin-1 (IL-1) (α and β), IL-6, IL-8, IL-10, IL-12, and tumor necrosis factor alpha (TNF-α) in pulmonary alveolar macrophages (PAMs) was assessed following experimental infection with porcine reproductive and respiratory syndrome virus (PRRSV) and/or Mycoplasma hyopneumoniae by using in vivo and in vitro models. The in vivo model consisted of pigs infected with PRRSV and/or M. hyopneumoniae and necropsied at 10, 28, or 42 days postinfection. Pigs infected with both pathogens had a greater percentage of macroscopic lung lesions, increased clinical disease, and slower viral clearance than pigs infected with either pathogen alone. The pigs infected with both PRRSV and M. hyopneumoniae had significantly increased levels of mRNA for many proinflammatory cytokines in PAMs collected by bronchoalveolar lavage (BAL) at all necropsy dates compared to those in uninfected control pigs. Increased levels of IL-1β, IL-8, IL-10, and TNF-α proteins in BAL fluid, as measured by enzyme-linked immunosorbent assay, confirmed the increased cytokine induction induced by the pathogens. An in vitro model consisted of M. hyopneumoniae-inoculated tracheal ring explants cultured with PRRSV-infected PAMs. PAMs were harvested at 6 or 15 h postinfection with either or both pathogens. The in vitro study detected increased IL-10 and IL-12 mRNA levels in PAMs infected with PRRSV at all time periods. In addition, IL-10 protein levels were significantly elevated in the culture supernatants in the presence of M. hyopneumoniae-inoculated tracheal ring explants. The increased production of proinflammatory cytokines in vivo and in vitro associated with concurrent M. hyopneumoniae and PRRSV infection may play a role in the increased rates of pneumonia associated with PRRSV infection. The increased levels of IL-10 may be a possible mechanism that PRRSV and M. hyopneumoniae use to exacerbate the severity and duration of pneumonia induced by PRRSV and modulate the respiratory immune response.

Interleukin-1α stimulates proinflammatory cytokine expression in human cardiac myofibroblasts

2009 ◽  
Vol 297 (3) ◽  
pp. H1117-H1127 ◽  
Author(s):  
Neil A. Turner ◽  
Anupam Das ◽  
Philip Warburton ◽  
David J. O'Regan ◽  
Stephen G. Ball ◽  
...  
Keyword(s):  
Protein Kinase ◽  
Mrna Expression ◽  
Signaling Pathways ◽  
P38 Mapk ◽  
Proinflammatory Cytokines ◽  
Enzyme Linked Immunosorbent Assay ◽  
Mrna Levels ◽  
Tnf Α ◽  
Interleukin 1Α ◽  
Cardiac Myofibroblasts

Cardiac myofibroblasts (CMF) play a key role in infarct repair and scar formation following myocardial infarction (MI) and are also an important source of proinflammatory cytokines. We postulated that interleukin-1α (IL-1α), a potential early trigger of acute inflammation post-MI, could stimulate human CMF to express additional proinflammatory cytokines. Furthermore, we hypothesized that these effects may be modulated by the anti-inflammatory cytokine interleukin-10 (IL-10). Human CMF were cultured from atrial biopsies from multiple patients. Interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and cardiotrophin-1 (CT-1) mRNA expression and secretion were measured using quantitative real-time RT-PCR and enzyme-linked immunosorbent assay. IL-1α (0.001–10 ng/ml, 0–6 h) stimulated IL-1β, TNF-α, and IL-6 mRNA expression with distinct temporal and concentration profiles, resulting in increased cytokine secretion. The response to IL-1α was much greater than with TNF-α. Neither IL-1α nor TNF-α treatment modulated CT-1 mRNA expression. Immunoblotting with phosphospecific antibodies revealed that IL-1α stimulated the extracellular signal-regulated kinase (ERK)-1/2, p38 mitogen-activated protein kinase (MAPK), c-Jun NH2-terminal kinase (JNK), phosphatidylinositol 3-kinase (PI 3-kinase)/protein kinase B (Akt), and nuclear factor (NF)-κB signaling pathways. Pharmacological inhibitor studies indicated roles for PI 3-kinase/Akt and NF-κB pathways in mediating IL-1β expression, and for NF-κB and p38 MAPK pathways in mediating TNF-α expression. IL-1α-induced IL-6 mRNA expression was reduced by p38 MAPK inhibition, but increased by ERK and JNK pathway inhibitors. IL-10 produced a consistent but modest reduction in IL-1α-induced IL-6 mRNA levels (not IL-1β or TNF-α), but this was not reflected by reduced IL-6 protein secretion. In conclusion, IL-1α stimulates human CMF to express IL-1β, TNF-α, and IL-6 via specific signaling pathways, responses that are unaffected by IL-10 exposure.

scholarly journals Upregulation of Cytokines Is Detected in the Placentas of Cattle Infected with Neospora caninum and Is More Marked Early in Gestation When Fetal Death Is Observed

2008 ◽  
Vol 76 (6) ◽  
pp. 2352-2361 ◽  
Author(s):  
Anne Rosbottom ◽  
E. Helen Gibney ◽  
Catherine S. Guy ◽  
Anja Kipar ◽  
Robert F. Smith ◽  
...  
Keyword(s):  
Protein Expression ◽  
Fetal Death ◽  
Neospora Caninum ◽  
Late Gestation ◽  
Enzyme Linked Immunosorbent Assay ◽  
Mrna Levels ◽  
Cytokine Mrna ◽  
Early Gestation ◽  
Tnf Α ◽  
Ifn Γ

ABSTRACT The protozoan parasite Neospora caninum causes fetal death after experimental infection of pregnant cattle in early gestation, but the fetus survives a similar infection in late gestation. An increase in Th1-type cytokines in the placenta in response to the presence of the parasite has been implicated as a contributory factor to fetal death due to immune-mediated pathological alterations. We measured, using real-time reverse transcription-PCR and enzyme-linked immunosorbent assay, the levels of cytokines in the placentas of cattle experimentally infected with N. caninum in early and late gestation. After infection in early gestation, fetal death occurred, and the levels of mRNA of both Th1 and Th2 cytokines, including interleukin-2 (IL-2), gamma interferon (IFN-γ), IL-12p40, tumor necrosis factor alpha (TNF-α), IL-18, IL-10, and IL-4, were significantly (P < 0.01) increased by up to 1,000-fold. There was extensive placental necrosis and a corresponding infiltration of CD4+ T cells and macrophages. IFN-γ protein expression was also highly increased, and a modest increase in transforming growth factor β was detected. A much smaller increase in the same cytokines and IFN-γ protein expression, with minimal placental necrosis and inflammatory infiltration, occurred after N. caninum infection in late gestation when the fetuses survived. Comparison of cytokine mRNA levels in separated maternal and fetal placental tissue that showed maternal tissue was the major source of all cytokine mRNA except for IL-10 and TNF-α, which were similar in both maternal and fetal tissues. These results suggest that the magnitude of the cytokine response correlates with but is not necessarily the cause of fetal death and demonstrate that a polarized Th1 response was not evident in the placentas of N. caninum-infected cattle.

scholarly journals PPARγ inhibits airway epithelial cell inflammatory response through a MUC1-dependent mechanism

2012 ◽  
Vol 302 (7) ◽  
pp. L679-L687 ◽  
Author(s):  
Yong Sung Park ◽  
Erik P. Lillehoj ◽  
Kosuke Kato ◽  
Choon Sik Park ◽  
Kwang Chul Kim
Keyword(s):  
Epithelial Cells ◽  
Culture Media ◽  
A549 Cells ◽  
Luciferase Reporter ◽  
Muc1 Expression ◽  
Mrna Levels ◽  
Airway Epithelial ◽  
Pparγ Agonist ◽  
Tnf Α ◽  
Primary Mouse

This study was conducted to examine the relationship between the peroxisome proliferator-associated receptor-γ (PPARγ) and MUC1 mucin, two anti-inflammatory molecules expressed in the airways. Treatment of A549 lung epithelial cells or primary mouse tracheal surface epithelial (MTSE) cells with phorbol 12-myristate 13-acetate (PMA) increased the levels of tumor necrosis factor (TNF)-α in cell culture media compared with cells treated with vehicle alone. Overexpression of MUC1 in A549 cells decreased PMA-stimulated TNF-α levels, whereas deficiency of Muc1 expression in MTSE cells from Muc1 null mice increased PMA-induced TNF-α levels. Treatment of A549 or MTSE cells with the PPARγ agonist troglitazone (TGN) blocked the ability of PMA to stimulate TNF-α levels. However, the effect of TGN required the presence of MUC1/Muc1, since no differences in TNF-α levels were seen between PMA and PMA plus TGN in MUC1/Muc1-deficient cells. Similarly, whereas TGN decreased interleukin-8 (IL-8) levels in culture media of MUC1-expressing A549 cells treated with Pseudomonas aeruginosa strain K (PAK), no differences in IL-8 levels were seen between PAK and PAK plus TGN in MUC1-nonexpressing cells. EMSA confirmed the presence of a PPARγ-binding element in the MUC1 gene promoter. Finally, TGN treatment of A549 cells increased MUC1 promoter activity measured using a MUC1-luciferase reporter gene, augmented MUC1 mRNA levels by quantitative RT-PCR, and enhanced MUC1 protein expression by Western blot analysis. These combined data are consistent with the hypothesis that PPARγ stimulates MUC1/Muc1 expression, thereby blocking PMA/PAK-induced TNF-α/IL-8 production by airway epithelial cells.

scholarly journals Thymic stromal lymphopoietin is released by human epithelial cells in response to microbes, trauma, or inflammation and potently activates mast cells

2007 ◽  
Vol 204 (2) ◽  
pp. 253-258 ◽  
Author(s):  
Zoulfia Allakhverdi ◽  
Michael R. Comeau ◽  
Heidi K. Jessup ◽  
Bo-Rin Park Yoon ◽  
Avery Brewer ◽  
...  
Keyword(s):  
Mast Cells ◽  
Epithelial Cell ◽  
Epithelial Cells ◽  
Immunoglobulin E ◽  
Interleukin 1 ◽  
Allergic Inflammation ◽  
Thymic Stromal Lymphopoietin ◽  
Microbial Products ◽  
Necrosis Factor

Compelling evidence suggests that the epithelial cell–derived cytokine thymic stromal lymphopoietin (TSLP) may initiate asthma or atopic dermatitis through a dendritic cell–mediated T helper (Th)2 response. Here, we describe how TSLP might initiate and aggravate allergic inflammation in the absence of T lymphocytes and immunoglobulin E antibodies via the innate immune system. We show that TSLP, synergistically with interleukin 1 and tumor necrosis factor, stimulates the production of high levels of Th2 cytokines by human mast cells (MCs). We next report that TSLP is released by primary epithelial cells in response to certain microbial products, physical injury, or inflammatory cytokines. Direct epithelial cell–mediated, TSLP-dependent activation of MCs may play a central role in “intrinsic” forms of atopic diseases and explain the aggravating role of infection and scratching in these diseases.

scholarly journals MiR-125b regulates inflammation in bovine mammary epithelial cells by targeting the NKIRAS2 gene

2021 ◽  
Vol 52 (1) ◽  
Author(s):  
Zhuo-Ma Luoreng ◽  
Da-Wei Wei ◽  
Xing-Ping Wang
Keyword(s):  
T Cells ◽  
Epithelial Cells ◽  
Dairy Cows ◽  
Mammary Epithelial Cells ◽  
Mammary Epithelial ◽  
Luciferase Reporter ◽  
Regulation Mechanism ◽  
Bovine Mammary Epithelial Cells ◽  
Tnf Α

AbstractMastitis is a complex inflammatory disease caused by pathogenic infection of mammary tissue in dairy cows. The molecular mechanism behind its occurrence, development, and regulation consists of a multi-gene network including microRNA (miRNA). Until now, there is no report on the role of miR-125b in regulating mastitis in dairy cows. This study found that miR-125b expression is significantly decreased in lipopolysaccharide (LPS)-induced MAC-T bovine mammary epithelial cells. Also, its expression is negatively correlated with the expression of NF-κB inhibitor interacting Ras-like 2 (NKIRAS2) gene. MiR-125b target genes were identified using a double luciferase reporter gene assay, which showed that miR-125b can bind to the 3′ untranslated region (3′ UTR) of the NKIRAS2, but not the 3′UTR of the TNF-α induced protein 3 (TNFAIP3). In addition, miR-125b overexpression and silencing were used to investigate the role of miR-125b on inflammation in LPS-induced MAC-T. The results demonstrate that a reduction in miR-125b expression in LPS-induced MAC-T cells increases NKIRAS2 expression, which then reduces NF-κB activity, leading to low expression of the inflammatory factors IL-6 and TNF-α. Ultimately, this reduces the inflammatory response in MAC-T cells. These results indicate that miR-125b is a pro-inflammatory regulator and that its silencing can alleviate bovine mastitis. These findings lay a foundation for elucidating the molecular regulation mechanism of cow mastitis.

scholarly journals TheBDKRB2 +9/-9 Polymorphisms Influence Pro-Inflammatory Cytokine Levels in Knee Osteoarthritis by Altering TLR-2 Expression: Clinical and in Vitro Studies

2016 ◽  
Vol 38 (3) ◽  
pp. 1245-1256 ◽  
Author(s):  
Shuo Chen ◽  
Lei Zhang ◽  
Ruonan Xu ◽  
Yunfan Ti ◽  
Yunlong Zhao ◽  
...  
Keyword(s):  
Knee Osteoarthritis ◽  
Inflammatory Cytokine ◽  
Molecular Mechanisms ◽  
Enzyme Linked Immunosorbent Assay ◽  
Mrna Levels ◽  
Knee Oa ◽  
Tnf Α ◽  
Cytokine Levels ◽  
Underlying Mechanisms

Background/Aims: The bradykinin B2 receptor (BDKRB2) +9/-9 gene polymorphisms have been shown to be associated with the susceptibility and severity of osteoarthritis (OA); however, the underlying mechanisms are unclear. In this study, we investigated the correlation between the BDKRB2 +9/-9 polymorphisms and pro-inflammatory cytokine levels in OA and the molecular mechanisms involved. Methods: A total of 156 patients with primary knee OA and 121 healthy controls were enrolled. The BDKRB2 +9/-9 polymorphisms were genotyped. The tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, and IL-8 levels were determined using Enzyme-linked immunosorbent assay (ELISA). The toll-like receptor (TLR)-2 and TLR-4 mRNA levels were determined by quantitative real-time PCR. The basal and bradykinin-stimulated pro-inflammatory cytokine secretion in human OA synoviocytes and the involvement of TLR-2 and mitogen-activated protein kinases (MAPKs) were investigated. Results: The presence of -9 bp genotype is associated with higher TNF-α, IL-6, and IL-8 levels and higher TLR-2 expression in OA patients. The basal and bradykinin-induced TLR-2 expressions in human OA synoviocytes were significantly reduced by specific inhibitors of p38, JNK1/2, and ERK1/2. Both the B2 receptor antagonist MEN16132 and TLR-2 silencing inhibited IL-6 and IL-8 secretion in human OA synoviocytes. Conclusion: The data suggested that the BDKRB2 +9/-9 polymorphisms influence pro-inflammatory cytokine levels in knee osteoarthritis by altering TLR-2 expression.

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