Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P10145 (IL-8)
 23,849 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

So far, the role of fibroblasts in inflammatory processes has been underestimated. We have previously shown that stimulation of fibroblasts with viruses or bacteria results in a simultaneous production of several cytokines, including interferon-beta, interleukin (IL) 6 and colony-stimulating factors. We here report that virally infected fibroblasts produce also a chemotactic factor for granulocytes. The activity is inducible not only by measles virus but also by IL 1 beta and the double-stranded RNA poly(rI).poly(rC). This factor, when purified to homogeneity, occurs as a 6-7-kDa protein doublet upon sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The pure protein is serologically related to a fully characterized granulocyte chemotactic peptide (GCP) from monocytes, designated IL8. Furthermore, the chemotactic factor from fibroblasts has an NH2-terminal sequence identical to that of GCP/IL8, small differences in NH2-terminal processing being observed. Finally, in addition to diploid fibroblasts, the osteosarcoma MG-63 cell line is also a producer of GCP/IL8. It can thus be concluded that GCP/IL8 can be produced by several cell types in response to infection and that fibroblasts can contribute to chemotaxis in inflammation.
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PMID:The chemotactic activity for granulocytes produced by virally infected fibroblasts is identical to monocyte-derived interleukin 8. 266 11

Interleukin (IL)-8 mRNA expression was investigated in human dental pulp fibroblast cultures after stimulation with lipopolysaccharide (LPS) prepared from Prevotella intermedia and inflammatory cytokines. The expression of IL-8 mRNA and the release of IL-8 induced by P. intermedia LPS in pulpal fibroblast cultures were detected by Northern blot analysis and ELISA, respectively. The sufficient concentration of P. intermedia LPS on the IL-8 mRNA expression was 0.1 microgram/ml in pulpal fibroblast cultures. IL-8 mRNA levels began to increase after 2 h of exposure, reached a maximum at 4 to 8 h, and declined after 48 h, reaching the unstimulated level by 60 h. IL-8 production by the pulpal fibroblasts began to increase after 8 h of exposure upon stimulation with 10 microgram/ml of P. intermedia LPS. By contrast Salmonella LPS and synthetic lipid A did not increase IL-8 mRNA concentrations in pulpal fibroblast cultures. Recombinant human IL-1 alpha, beta, and tumor necrosis factor-alpha were capable of stimulating these cells to express IL-8 mRNA but natural human interferon-beta, gamma, and recombinant human IL-6 were incapable in our assay. These results suggest that pulpal fibroblasts are immunoresponsive cells and can elaborate IL-8 upon stimulation with P. intermedia LPS.
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PMID:Interleukin-8 gene expression by human dental pulp fibroblast in cultures stimulated with Prevotella intermedia lipopolysaccharide. 861 87

We studied the effects of interferon-beta (IFN-beta) on the differentiation of dendritic cells (DC) obtained by culturing plastic-adherent peripheral blood mononuclear cells (PBMC) from a total of 30 healthy volunteers in the presence of granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-4 (IL-4). First, we found that the addition of IFN-beta at the initiation of the culture did not modify DC morphology but caused a reproducible and statistically significant upregulation of HLA-DR, CD86, and CD80 surface expression. CD1a expression was significantly reduced, and CD40 expression was unchanged. We then determined the influence of IFN-beta on the production of cytokines by DC. DC differentiated in the presence of IFN-beta secreted significantly less IL-12 (p40 and p70) both spontaneously and on activation by fibroblasts transfected with the CD40L gene. This effect of IFN-beta was dose dependent and selective, as it was not observed for IL-6, IL-8, and tumor necrosis factor-alpha (TNF-alpha). As a consequence, DC differentiated in the presence of IFN-beta induced significantly less IFN-gamma secretion by alloreactive T cells, whereas they were more efficient than control DC in eliciting IL-5 secretion. We conclude that the direct action of IFN-beta on DC causes inhibition of their ability to secrete IL-12 in response to CD40 ligation and to elicit Th1 type responses.
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PMID:IFN-beta interferes with the differentiation of dendritic cells from peripheral blood mononuclear cells: selective inhibition of CD40-dependent interleukin-12 secretion. 1038 59

Cytokine expression in enterovirus infections of the heart may trigger inflammation and have detrimental effects on myocytes. However, the induction of cytokines in human myocardial cells by cardiotropic enteroviruses, for example, Coxsackievirus B3 (CVB3), was not yet demonstrated. Fibroblasts are the predominant cell type of the myocardial interstitium before inflammatory infiltration develops. Hence, we investigated, by enzyme immunoassays, reverse transcription-quantitative polymerase chain reaction (RT-qPCR), and nucleic acid sequence-based amplification (NASBA), whether CVB3 induces cytokine expression in cultured human myocardial fibroblasts. As early as 3 hours after infection, RT-qPCR demonstrated a 2-fold increase of interleukin (IL)-6 and IL-8 mRNA compared with basal transcription, resulting in a significant increase of IL-6 and IL-8 to a median level of 1500 pg/mL (range, 1246 to 1858) and 529 pg/mL (range, 428 to 601) in culture supernatants, respectively. IL-6 and IL-8 expression returned to basal levels within 3 and 5 days, respectively, despite a persistent (carrier-state) CVB3 infection. For comparison, IL-6 and IL-8 were induced in dermal fibroblasts later than 3 days after CVB3 infection. Although the low-level IL-1alpha transcription of myocardial fibroblasts was not significantly increased, IL-1alpha was released from cells to culture supernatants 5 days after infection. Furthermore, a suppression of interferon-beta transcription was demonstrated up to 24 hours after CVB3 infection of myocardial fibroblasts by highly sensitive NASBA. In conclusion, our results demonstrate a heart-specific pattern of a rapid and transient induction of proinflammatory cytokines after CVB3 infection, whereas the expression of protective interferon-beta was suppressed by CVB3.
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PMID:Transient induction of cytokine production in human myocardial fibroblasts by coxsackievirus B3. 1076 8

Interleukin (IL)-8, a prototypic chemokine, is rapidly induced by the pro-inflammatory cytokine IL-1 but is barely detectable in noninduced cells. Although there is clear evidence that the transcription factor NF-kappaB plays a central role in inducible IL-8 transcription, very little is known about the cis-elements and trans-acting factors involved in silencing of the IL-8 promoter. By sequence comparison with the interferon-beta promoter, we found a negative regulatory element (NRE) in the IL-8 promoter overlapping partially with the NF-kappaB response element. Here we show that an NF-kappaB-repressing factor (NRF) binds to the IL-8 promoter NF-kappaB-NRE. Reduction of cellular NRF by expressing NRF antisense RNA results in spontaneous IL-8 gene expression. In contrast, IL-1-induced IL-8 secretion is strongly impaired by expressing NRF antisense RNA. Mutation of the NRE site results in loss of NRF binding and increased basal IL-8 transcription. On the other hand IL-1-induced IL-8 transcription is decreased by mutating the NRE. These data provide evidence for a dual role of the NRF in IL-8 transcription. Although in the absence of stimulation it is involved in transcriptional silencing, in IL-1-induced cells it is required for full induction of the IL-8 promoter.
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PMID:The NF-kappa b repressing factor is involved in basal repression and interleukin (IL)-1-induced activation of IL-8 transcription by binding to a conserved NF-kappa b-flanking sequence element. 1107 90

Influenza A is a highly contagious single-stranded RNA virus that infects both the upper and lower respiratory tracts of humans. The host innate immune Toll-like receptor (TLR) 3 was shown previously in cells of myeloid origin to recognize the viral replicative, intermediate double-stranded RNA (dsRNA). Thus, dsRNA may be critical for the outcome of the infection. Here we first compared the activation triggered by either influenza A virus or dsRNA in pulmonary epithelial cells. We established that TLR3 is constitutively expressed in human alveolar and bronchial epithelial cells, and we describe its intracellular localization. Expression of TLR3 was positively regulated by the influenza A virus and by dsRNA but not by other inflammatory mediators, including bacterial lipopolysaccharide, the cytokines tumor necrosis factor-alpha and interleukin (IL)-1beta, and the protein kinase C activator phorbol 12-myristate 13-acetate. We also demonstrated that TLR3 contributes directly to the immune response of respiratory epithelial cells to influenza A virus and dsRNA, and we propose a molecular mechanism by which these stimuli induce epithelial cell activation. This model involves mitogen-activated protein kinases, phosphatidylinositol 3-kinase/Akt signaling, and the TLR3-associated adaptor molecule TRIF but not MyD88-dependent activation of the transcription factors NF-kappaB or interferon regulatory factor/interferon-sensitive response-element pathways. Ultimately, this signal transduction elicits an epithelial response that includes the secretion of the cytokines IL-8, IL-6, RANTES (regulated on activation normal T cell expressed and secreted), and interferon-beta and the up-regulation of the major adhesion molecule ICAM-1.
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PMID:Involvement of toll-like receptor 3 in the immune response of lung epithelial cells to double-stranded RNA and influenza A virus. 1557

During poliovirus infection, anterograde traffic between the endoplasmic reticulum and the Golgi is inhibited due to the action of 3A, an 87 amino acid viral protein. The ability of poliovirus protein 3A to inhibit ER-to-Golgi traffic is not required for virus growth. Instead, we have suggested that the inhibition of host protein secretion, shown to reduce the secretion of interferon-beta, IL-6, and IL-8 and the expression of both newly synthesized MHC class I and TNF receptor in the plasma membrane of infected cells, affects growth in host organisms. To determine whether the ability of poliovirus 3A to inhibit ER-to-Golgi traffic is conserved, the ability of 3A proteins from several picornaviruses, including human rhinovirus 14, foot-and-mouth disease virus, enterovirus 71, hepatitis A, and Theiler's virus, was tested. Only the 3A proteins from another poliovirus, Sabin 3, and closely related coxsackievirus B3 inhibited ER-to-Golgi traffic as effectively as the 3A protein from poliovirus Mahoney type 1. Site-directed mutagenesis based on these findings and the three-dimensional structure of the amino-terminal domain of poliovirus 3A protein revealed that residues in the unstructured amino terminus of 3A are critical for the inhibition of host protein secretion.
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PMID:Inhibition of cellular protein secretion by picornaviral 3A proteins. 1591 17

The role of extracellular proteolysis in innate and adaptive immunity and the interplay between cytokines, chemokines and proteinases are gradually becoming recognized as critical factors in autoimmune processes. Many of the involved proteinases, including those of the plasminogen activator and matrix metalloproteinase cascades, and also several cytokines and chemokines, are glycoproteins. The stability, interactions with inhibitors or receptors, and activities of these molecules are fine-controlled by glycosylation. We studied gelatinase B or matrix metalloproteinase-9 (MMP-9) as a glycosylated enzyme involved in autoimmunity. In the joints of rheumatoid arthritis patients, CXC chemokines, such as interleukin-8/CXCL8, recruit and activate neutrophils to secrete prestored neutrophil collagenase/MMP-8 and gelatinase B/MMP-9. Gelatinase B potentiates interleukin-8 at least tenfold and thus enhances neutrophil and lymphocyte influxes to the joints. When cartilage collagen type II is cleaved at a unique site by one of several collagenases (MMP-1, MMP-8 or MMP-13), it becomes a substrate of gelatinase B. Human gelatinase B cleaves the resulting two large collagen fragments into at least 33 peptides of which two have been shown to be immunodominant, i.e., to elicit activation and proliferation of autoimmune T cells. One of these two remnant epitopes contains a glycan which is important for its immunoreactivity. In addition to the role of gelatinase B as a regulator in adaptive immune processes, we have also demonstrated that it destroys interferon-beta, a typical innate immunity effector molecule and therapeutic cytokine in multiple sclerosis. Furthermore, glycosylated interferon-beta, expressed in Chinese hamster ovary cells, was more resistant to this proteolysis than recombinant interferon-beta from bacteria. These data not only prove that glycosylation of proteins is mechanistically important in the pathogenesis of autoimmune diseases, but also show that targeting of glycosylated proteinases or the use of glycosylated cytokines seems also critical for the treatment of autoimmune diseases.
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PMID:Remnant epitopes, autoimmunity and glycosylation. 1643 62

Niemann-Pick disease type C (NPC) is an inherited lipid storage disorder caused by mutations in NPC1 or NPC2 genes. Loss of function of either protein results in the endosomal accumulation of cholesterol and other lipids, progressive neurodegeneration, and robust glial cell activation. Here, we report that cultured human NPC fibroblasts secrete interferon-beta, interleukin-6 (IL-6), and IL-8, and contain increased levels of signal transducers and activators of transcription (STATs). These cells also contained increased levels of Toll-like receptor 4 (TLR4) that accumulated in cholesterol-enriched endosomes/lysosomes, and small interfering RNA knockdown of this receptor reduced cytokine secretion. In the NPC1-/- mouse brain, glial cells expressed TLR4 and IL-6, whereas both glial and neuronal cells expressed STATs. Genetic deletion of TLR4 in NPC1-/- mice reduced IL-6 secretion by cultured fibroblasts but failed to alter STAT levels or glial cell activation in the brain. In contrast, genetic deletion of IL-6 normalized STAT levels and suppressed glial cell activation. These findings indicate that constitutive cytokine secretion leads to activation of STATs in NPC fibroblasts and that this secretion is partly caused by an endosomal accumulation of TLR4. These results also suggest that similar signaling events may underlie glial cell activation in the NPC1-/- mouse brain.
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PMID:Endosomal accumulation of Toll-like receptor 4 causes constitutive secretion of cytokines and activation of signal transducers and activators of transcription in Niemann-Pick disease type C (NPC) fibroblasts: a potential basis for glial cell activation in the NPC brain. 1731 84

Pneumonia virus of mice (PVM; family Paramyxoviridae, subfamily Pneumovirinae) is a natural respiratory pathogen of rodent species and an important new model for the study of severe viral bronchiolitis and pneumonia. However, despite high virus titers typically detected in infected mouse lung tissue in vivo, cell lines used routinely for virus propagation in vitro are not highly susceptible to PVM infection. We have evaluated several rodent and primate cell lines for susceptibility to PVM infection, and detected highest virus titers from infection of the mouse monocyte-macrophage RAW 264.7 cell line. Additionally, virus replication in RAW 264.7 cells induces the synthesis and secretion of proinflammatory cytokines relevant to respiratory virus disease, including tumor necrosis factor-alpha (TNF-alpha), interferon-beta (IFN-beta), macrophage inflammatory proteins 1alpha and 1beta (MIP-1alpha and MIP-1beta) and the functional homolog of human IL-8, mouse macrophage inflammatory peptide-2 (MIP-2). Identification and characterization of a rodent cell line that supports the replication of PVM and induces the synthesis of disease-related proinflammatory mediators will facilitate studies of molecular mechanisms of viral pathogenesis that will complement and expand on findings from mouse model systems.
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PMID:Efficient replication of pneumonia virus of mice (PVM) in a mouse macrophage cell line. 1754 63


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