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

Ischemia-reperfusion and hyperoxia-induced pulmonary injury are associated with the presence of activated neutrophils (PMN) and cellular injury. Although the signals orchestrating the directed migration of these PMN during the pathogenesis of these disease states remain to be fully elucidated, it appears they may be dependent upon the production of certain neutrophil activating/chemotactic factors such as C5a, leukotriene B4, platelet-activating factor, and IL-8. The production of the latter chemotaxin by mononuclear phagocytes is especially intriguing as these cells can mediate inflammatory cell migration by either directly generating IL-8, or by inducing its production from surrounding nonimmune cells. In light of these observations, we propose that ischemia-reperfusion and oxidant stress, in vivo, may be simulated by anoxia-hyperoxia induced stress in vitro, and that this stress may act as a stimulus for the production of IL-8. We now show that isolated human blood monocytes respond to such an oxygen stress with augmented production of IL-8. In initial studies, monocytes demonstrated an increase in the production of IL-8 under anoxic preconditioning. Subsequently, monocytes were cultured under one of the following conditions for 24 h: (a) room air/5% CO2; (b) 95% N2/5% CO2 for 6 h, followed by room air/5% CO2 for 18 h; (c) 95% N2/5% CO2 for 6 h, followed by 95% O2/5% CO2 for 18 h; (d) room air/5% CO2 for 6 h, followed by 95% O2/5% CO2 for 18 h; or (e) 95% O2/5% CO2. Supernatants were isolated and analyzed for IL-8 antigen by specific IL-8 ELISA, demonstrating the production of monocyte-derived IL-8: 5.9 +/- 0.9, 11.4 +/- 1.7, 21.1 +/- 2.3, 14.6 +/- 2.4, and 26.3 +/- 4.7, ng/ml by designated conditions a, b, c, d, and e listed above, respectively. This variance in IL-8 production reflects altered rates of transcription as shown by Northern blot analysis and nuclear run-off assay. Furthermore, when monocytes were concomitantly treated with LPS (100 ng/ml) under in vitro hyperoxic conditions, both IL-8 steady-state mRNA and antigenic activity were two- to threefold greater than under room air conditions. The association of anoxic preconditioning and oxygen stress with augmented production of monocyte-derived IL-8 support the potential role for ischemia-reperfusion and hyperoxia-induced IL-8 production in vivo, providing a possible mechanism for PMN migration/activation in disease states characterized by altered tissue oxygenation.
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PMID:Anoxia-hyperoxia induces monocyte-derived interleukin-8. 152 34

Interleukin-8 (IL-8) is a potent chemotactic protein for polymorphonuclear leukocytes (PMN). Here we examine whether PMN synthesize and release IL-8 in response to stimulation by leukotriene B4 (LTB4). PMN isolated from normal heparinized peripheral human blood were incubated in RPMI culture medium at 37 degrees C in 5% CO2, with and without LTB4. The culture supernatants were tested for IL-8 bioactivity through chemotactic activity measurements with and without neutralizing anti-IL-8 serum. Immunoreactive IL-8 was quantified by ELISA, and de novo IL-8 synthesis was evaluated by metabolic labeling with [35S]cysteine followed by immunoprecipitation. LTB4 stimulated PMN to produce IL-8 in a dose- and time-dependent manner. The IL-8 concentrations reached maximal levels after 16 h of incubation with LTB4. Significant increases in IL-8 production occurred with LTB4 doses of 10 to 1,000 nM/ml. Immunoprecipitation of labeled IL-8 documented new synthesis of IL-8 by LTB4-treated PMN. Northern blot analysis of total RNA from PMN using a 30 mer oligonucleotide for IL-8 demonstrated increased mRNA expression in LTB4-stimulated PMN compared with untreated PMN. These data show that peripheral blood PMN can be stimulated by LTB4 to synthesize and secrete biologically active IL-8. PMN and other cells capable of producing LTB4 may induce IL-8 protein production by inflammatory PMN and thereby amplify or perpetuate the acute inflammatory response by recruiting additional PMN into an inflammatory site.
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PMID:Leukotriene B4 stimulates human polymorphonuclear leukocytes to synthesize and release interleukin-8 in vitro. 800 41

Erythrocytes have long been appreciated as transporters and exchangers of O2 and CO2 between the lungs and the tissues. Here we examine the role of erythrocytes as potential mediators of inflammatory processes by assessing their ability to bind to a number of inflammatory peptides of the chemokine (for chemoattractant cytokine) superfamily. Radiolabeled chemokines of either the C-X-C (IL-8, MGSA/gro, NAP-2) or C-C (RANTES, MCP-1) class bind reversibly to red cell surface receptors numbering 1000-9000 sites/cell with a Kd of approximately 5 nM. In contrast to what is seen for chemokine binding to target inflammatory cells, chemokines of either class displace heterologous chemokines, indicating that the proteins are competing for a promiscuous receptor. Chemical cross-linking with radiolabeled chemokines reveals a 30-38-kilodalton protein on the red cell surface, and cross-linking is inhibited in the presence of heterologous unlabeled chemokines. These data show that red blood cells possess a multispecific receptor for the newly identified chemokine superfamily of inflammatory cytokines, and thus the red cell may play a novel role as a regulator of inflammatory processes.
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PMID:Identification of a promiscuous inflammatory peptide receptor on the surface of red blood cells. 838 55

Although studies of nitrogen dioxide (NO2) inhalation, in both animals and humans, have demonstrated that this agent can cause epithelial cell damage and inflammation of the airway epithelium, the mechanisms underlying these effects are not well understood. We have cultured human bronchial epithelial cells, as explant cultures from surgical tissue, and studied these firstly from their ability to constitutively synthesize specific proinflammatory cytokines and then investigated the effect of exposure to NO2 on the generation of these cytokines. Constitutive synthesis of cytokines was evaluated by analysis of both the expression of the mRNA for interleukin (IL)-1 beta, IL-4, IL-8, granulocyte/macrophage colony-stimulating factor (GM-CSF), tumor necrosis factor-alpha (TNF-alpha), and interferon-gamma (IFN-gamma), by the polymerase chain reaction (PCR), and by immunocytochemical staining for the presence of cell-associated IL-1 beta, IL-8, GM-CSF, TNF-alpha, and IFN-gamma, using specific monoclonal and polyclonal antibodies directed towards these cytokines. Release of IL-4, IL-8, GM-CSF, TNF-alpha, and IFN-gamma following exposure to 5% CO2 in air or 400 ppb and 800 ppb NO2 for 6 h was investigated by enzyme-linked immunosorbent assay. PCR demonstrated that the human bronchial epithelial cells expressed the mRNA for IL-1 beta, IL-8, GM-CSF, and TNF-alpha but not for IL-4 and IFN-gamma. Immunocytochemical staining confirmed the presence of endogenous IL-1 beta, IL-8, GM-CSF, and TNF-alpha.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Effect of nitrogen dioxide on synthesis of inflammatory cytokines expressed by human bronchial epithelial cells in vitro. 839 64

Interleukin-8 (IL-8) is a potent chemotactic factor for polymorphonuclear leukocytes (PMN). Here we examine whether PMN synthesize and release IL-8 in response to stimulation by selected inflammatory cytokines. PMN isolated from normal heparinized peripheral human blood were incubated in RPMI culture medium at 37 degrees C in 5% CO2, with and without granulocyte/macrophage colony-stimulating factor (GM-CSF). The culture supernatants were tested for chemotactic activity using a modified Boyden chamber. Immunoreactive IL-8 protein was measured by ELISA with a monoclonal antibody specific for IL-8. GM-CSF (0.01 to 50 ng/ml) stimulated PMN to produce chemotactic activity in a dose- and time-dependent manner. The amount of chemotactic activity reached maximal levels after 3 h of incubation with GM-CSF. Treatment of culture media supernatants with rabbit antiserum against IL-8 blocked the GM-CSF-induced chemotactic activity. IL-8 protein concentrations detected by ELISA closely paralleled the chemotactic bioactivity in both the dose-response and kinetic studies. Northern blot analysis of total RNA from PMN using a 30 mer oligonucleotide complementary to mRNA for IL-8 yielded a single 1.6-kb band. Its intensity increased 4-fold 2 h after treatment of PMN with GM-CSF. These data suggest that peripheral blood PMN can be stimulated by GM-CSF to synthesize and secrete bioactive IL-8. Since both IL-8 and GM-CSF accumulate in sites of acute inflammation, PMN may induce IL-8 gene expression in response to GM-CSF and thereby amplify the acute inflammatory response by recruiting additional PMN into inflammatory sites.
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PMID:Granulocyte/macrophage colony-stimulating factor stimulates human polymorphonuclear leukocytes to produce interleukin-8 in vitro. 841 54

Studies of in vivo inhalation of nitrogen dioxide (NO2) have demonstrated a transient pulmonary inflammation. This study was done to determine the contribution of airway epithelial cells to the release of inflammatory mediators following NO2 exposure. Confluent cultures of the human bronchial epithelial cell line BEAS-2B on Transwell-Col filters were exposed for 1 h to air or NO2 up to 1.5 ppm with the apical fluids removed with 5% CO2 at 37 degrees C. The cells were hydrated with Hanks' Balanced Salt Solution (HBSS) in the basolateral compartment. Sequential reverse transcription and quantitative cDNA amplification (RT-PCR) was used to measure inflammatory mediator mRNA abundance in BEAS-2B cultures. When compared to air-exposed cells, NO2 induced increases in IL-6 (23.4-fold) and IL-8 (30.9-fold) mRNA abundance. The NO2-dependent increases in mRNA expression reached a maximum between 0 and 1 h post exposure and returned to baseline levels within 24 h. IL-6 and IL-8 proteins as measured by enzyme-linked immunosorbent assays (ELISA) were also elevated in supernatants recovered from NO2-exposed BEAS-2B cells. These studies suggest that exposure to NO2 induces the synthesis and release of inflammatory mediators from airway epithelial cells that may participate in the pathogenesis of airway disease.
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PMID:[In vitro exposure of a human bronchial epithelial cell line with nitrogen dioxide induces enhanced transcription and liberation of pro-inflammatory cytokines]. 858 42

The present study was designed to investigate the in vitro effects of potential therapeutic agents on cytokine production by five HTVL-I-infected T cell clones (TCC) established from the ocular fluid of patients with HTLV-I uveitis. Each of the five HTLV-I-infected TCC was cultured at 1 x 10(6) cells/ml with or without an immunosuppressive agent (hydrocortisone, FK506, rapamycin, indomethacin, or prostaglandin E2) for 22 hr in humidified 5% CO2 in air at 37 C. The production of various cytokines in the culture supernatant from each TCC was measured by ELISA. The HTLV-I-infected TCC produced high amounts of IL-1 alpha, IL-3, IL-6, IL-8, TNF-alpha, IFN-gamma, and GM-CSF, and low but significant levels of IL-2 and IL-10 without any stimuli. Hydrocortisone severely depressed the production by these TCC of all the cytokines except for IL-2, which was slightly increased. Prostaglandin E2 depressed the production of IL-1 alpha, while it up-regulated the production of IL-6, TNF-alpha, and IFN-gamma. Rapamycin depressed the production of IL-6 and TNF-alpha, and FK506 depressed the production of TNF-alpha. Hydrocortisone also severely depressed the cytokine production by PHA-stimulated peripheral blood mononuclear cells obtained from healthy volunteers. Of the immunosuppressive agents tested, hydrocortisone exhibited the strongest suppression of cytokine production by HTLV-I-infected TCC. This result was in agreement with the in vivo effects of hydrocortisone in patients with HTLV-I uveitis. These TCC will be useful in investigating the effects of potential therapeutic agents for HTLV-I uveitis in vitro.
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PMID:In vitro effects of immunosuppressive agents on cytokine production by HTLV-I-infected T cell clones derived from the ocular fluid of patients with HTLV-I uveitis. 880 2

Soot particles, asbestos fibres and irritant gas are common air pollutants which are able to induce lung and airway pulmonary injury. The aim of this study was to investigate the effect of a simultaneous NO2 and particle or fibre exposure on the proinflammatory specific mRNA expression and protein secretion of human alveolar macrophages (AM) in comparison to only particle or fibre exposed AM. AM were simultaneously exposed to FR 101, P 90, TiO2 or Chrysotile B at a concentration of 100 microg/10(6) cells and to NO2 at a concentration of 1.0 ppm for 30 min. Particle or fibre exposure of the AM was continued in humidified air at 5% CO2 and 37 degrees C for an additional hour (harvesting of total RNA) or additional 7 hrs (harvesting of culture supernatant). The mRNA expression of the proinflammatory cytokines IL-1beta, IL-6, IL-8 and TNF-alpha of NO2-particle/fibre co-exposed AM and only particle or fibre exposed AM was detected using specific RT-PCR. IL-1beta-, IL-6-, IL-8- and TNF-alpha-specific protein secretion was measured by ELISA. Cytotoxicity was detected by lactatedehydrogenase quantification in the culture supernatant. We observed an increased IL-1beta-, IL-6-, IL-8- and TNF-alpha-specific mRNA expression of particle or fibre exposed AM, which was decreased after an additional NO2 exposure. Also the particle or fibre exposure induced significant increase in IL-1beta-, IL-6-, IL-8 and TNF-alpha-release of AM which was decreased after an additional NO2 exposure (p <0.031). The relative cytotoxicity of the NO2-particle/fibre co-exposure was higher than the particle or fibre induced cytotoxicity, but mostly <10%. Therefore it is concluded that particle or fibre exposure may result in an increase in proinflammatory cytokine release by AM, which may be decreased by toxic NO2 due to the oxidative potential (e.g. lipidperoxydation) of this irritant gas. Particle, asbestos fibre and irritant gas exposure may induce airway and pulmonary injury by the activation of AM and consecutive proinflammatory cytokine release.
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PMID:Additional NO2 exposure induces a decrease in cytokine specific mRNA expression and cytokine release of particle and fibre exposed human alveolar macrophages. 1006 41

Due to their peripheral location in the dental pulp and their cellular extension into dentin, odontoblasts are the first pulpal cells to encounter dental pathogens. The association of odontoblasts with immunoglobulins and dendritic cells during microbial invasion of dentin implies that these cells may possess a role in the innate and adaptive pulpal immune responses, however this has not been examined. A pivotal step in the innate immune response is the detection of foreign antigen and the recruitment of immune effector cells to the area. IL-8 is a potent chemotactic cytokine that plays an important role in the inflammatory response. The purpose of this study was to determine if odontoblasts are capable of expressing the pro-inflammatory chemokine IL-8. Human odontoblasts from intact, noncarious third molars were maintained in culture and exposed to Escherichia coli lipopolysaccharide (LPS) (serotype 055:B5) on day 4 for 8-10 h in a humidified 5% CO2 incubator. Control and experimental samples were assayed by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot for the production of IL-8 mRNA and protein. Analysis of the PCR products revealed that cells of the odontoblast layer maintained in this culture model constitutively expressed low levels of IL-8, which were increased in response to E. coli LPS exposure. Western blotting confirmed that the mRNA was translated into protein. These results imply that odontoblasts are capable of producing of pro-inflammatory mediators, thereby actively participating in the recruitment of neutrophils in response to bacterial by-products.
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PMID:Expression of IL-8 by cells of the odontoblast layer in vitro. 1023 62

This study was designed to investigate VEGF production from peripheral blood mononuclear cells (PBMC) from patients with rheumatoid arthritis (RA) compared with healthy controls and to identify the predominant cellular source in PBMC isolated from RA patients. The regulation of PBMC VEGF production by cytokines and synovial fluid (SF) was studied. PBMC were isolated from RA patients and healthy controls and stimulated with lipopolysaccharide (LPS), IL-1beta, IL-4, IL-6, IL-8, IL-10, TNF-alpha and transforming growth factor-beta (TGF-beta) isoforms for varying time points up to 72 h at 37 degrees C/5% CO2. The effect of SF on VEGF secretion by PBMC was also studied. Supernatant VEGF levels were measured using a flt-1 receptor capture ELISA. RA patients had significantly higher spontaneous production of VEGF compared with controls, and monocytes were identified as the predominant cellular source. RA PBMC VEGF production was up-regulated by TGF-beta isoforms and TNF-alpha and down-regulated by IL-4 and IL-10, with no effect observed with IL-1beta, IL-6 and IL-8. Antibody blocking experiments confirmed that TNF-alpha and not TGF-beta isoforms in SF increased VEGF secretion by RA PBMC. These results emphasize the importance of monocytes as a source of VEGF in the pathophysiology of RA. Several cytokines known to be present in SF can modulate the level of VEGF secretion, but the predominant effect of SF in VEGF up-regulation is shown to be dependent on TNF-alpha.
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PMID:Peripheral blood mononuclear cells from patients with rheumatoid arthritis spontaneously secrete vascular endothelial growth factor (VEGF): specific up-regulation by tumour necrosis factor-alpha (TNF-alpha) in synovial fluid. 1040 32


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