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)

Recombinant human monocyte-derived interleukin-8 (IL-8M), recombinant human endothelium-derived IL-8 (IL-8E), and a recombinant human truncated form of IL-8 (IL-8T) stimulated a time-dependent (t 1/2 approximately 2-3 s) and concentration-dependent (0.1-100 nM) release of azurophil (myeloperoxidase) and specific (vitamin B12 binding protein, gelatinase) granule constituents from cytochalasin B-treated human neutrophils (HNs) wherein IL-8T = IL-8M greater than IL-8E. An increase in the cytosolic free calcium concentration ([Ca2+]i) was greater in IL-8T- than in IL-8M- or IL-8E-activated HNs, and IL-8T was more potent than either IL-8M or IL-8E in sequentially desensitizing the HNs to the effects of the other IL-8 forms. IL-8 induced a time- and concentration-dependent (0.1-100 nM) increase in the production of inositol 1,4,5-trisphosphate (IP3) in HNs. U-73122 (1-[6-[[17 beta-3-methoxyestra-1,3,5(10)-trien-17- yl]amino]hexyl]-1H-pyrrole-2,5-dione), a potent inhibitor of phospholipase C-catalyzed events in HNs, suppressed IL-8-triggered IP3 production, increased [Ca2+]i and granule exocytosis in HNs. The membrane-associated activity of the alpha and beta subtypes of protein kinase C was significantly enhanced in IL-8-activated cells.
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PMID:Postreceptor events associated with human neutrophil activation by interleukin-8. 132 42

IL-8 has been characterized primarily as a polymorphonuclear leukocyte (PMN) chemoattractant and proinflammatory mediator. Recently, we have reported that [Ala-IL-8]77 is secreted by activated cultured human endothelial cells and can function as a potent inhibitor of PMN adhesion to these monolayers. The pathophysiologic relevance of this in vitro observation was examined by determining the effects of intravascular or extravascular administration of IL-8 on PMN emigration at sites of acute inflammation in the skin of NZW rabbits. An i.v. bolus of [Ala-IL-8]77 (12 micrograms/kg) produced a marked and selective reduction of circulating PMN within 3 min, which returned toward preinjection levels within 30 min, and subsequently exceeded this level. A similar response was observed for circulating radiolabeled PMN, and gamma-scintigraphy determined that the lungs were the primary site of leukosequestration. During the 30- to 150-min interval after i.v. infusion of [Ala-IL-8]77, PMN emigration into acute inflammatory sites, elicited by various chemoattractants or cytokines, was significantly reduced, as judged histologically and quantitated with 51Cr-labeled PMN and myeloperoxidase measurements. Intravenous administration of [Ser-IL-8]72 yielded similar results. This inhibitory effect of i.v. IL-8 was transient and reinducible and did not reflect a suppression of the responsiveness of circulating PMN to chemoattractants. Intradermal injections of [Ala-IL-8]77 or [Ser-IL-8]72 induced dose-dependent PMN accumulation, which also was significantly reduced by i.v. administration of either form of IL-8. These results indicate that i.v. IL-8 can function as a PMN-directed leukocyte adhesion inhibitor and suggest that local secretion of IL-8 by activated endothelium may differentially modulate leukocyte-endothelial interactions at sites of acute inflammation.
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PMID:Intravascular IL-8. Inhibitor of polymorphonuclear leukocyte accumulation at sites of acute inflammation. 165 Mar 87

1 We studied the effects of a form of interleukin-8 (i.e., [Ala-IL8]77) on endothelial dysfunction and myocardial injury in rabbits. Pentobarbitone-anaesthetized rabbits were subjected to 1.5 h occlusion of the marginal coronary artery and 3.5 h reperfusion. [Ala-IL8]77 (50 micrograms or its vehicle) was given i.v. as a bolus 10 min prior to reperfusion. [Ala-IL8]77 was also studied in isolated perfused hearts of rabbits. 2 Myocardial ischaemia plus reperfusion in untreated rabbits produced severe endothelial dysfunction and myocardial injury, including marked myocardial necrosis, elevated cardiac myeloperoxidase (MPO) activity in ischaemic cardiac tissue, and loss of response of marginal coronary rings to the endothelium-dependent vasodilators, acetylcholine (ACh) and A23187. 3 Administration of [Ala-IL8]77 10 min prior to reperfusion resulted in significant protective effects in post-ischaemic reperfusion. Compared with untreated rabbits, [Ala-IL8]77 caused a reduced necrotic zone (P less than 0.01), lower MPO activity in the necrotic zone (P less than 0.05), and significantly preserved vasorelaxant responses of marginal coronary artery rings to endothelium-dependent vasodilators, ACh (P less than 0.001) and A23187 (P less than 0.001). 4 These results indicate that myocardial ischaemia and reperfusion result in a severe endothelial dysfunction and myocardial injury which involved the interaction of neutrophils and endothelial cells. However, [Ala-IL8]77 did not appear to exert a direct endothelial protective effect in the absence of neutrophils in rabbit isolated perfused hearts. 5 Inhibition of neutrophil accumulation in the myocardium, perhaps by prevention of endothelial dysfunction resulting from [Ala-IL8]77, leads to significant protective effects in ischaemia and reperfusion in rabbits.
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PMID:Cardioprotective and endothelial protective effects of [Ala-IL8]77 in a rabbit model of myocardial ischaemia and reperfusion. 165 42

Purification of monocyte-derived NAP-1/IL-8 by preparative reversed-phase (RP)-HPLC led to the detection of a second peak with polymorphonuclear leukocyte (PMNL)-activating (degranulation, chemotaxis) properties. The monokine responsible for this biological activity, which we tentatively termed NAP-3, could be purified to homogeneity by three different RP-HPLC steps. Tricine-SDS-PAGE analysis gave a single line at Mr 5.3 kD (NAP-1/IL-8 = 5.8 kD). NH2-terminal amino acid sequence analysis read as a major sequence (ASVATELRXCXLQT. .), which shows greater than 40% homology to that of NAP-1/IL-8. The sequence is identical to that found for the 13-kD moiety of melanoma growth stimulating activity (MGSA) and the product of the oncogene gro. Determination of neutrophil chemotactic activity of NAP-3 revealed a typical bell-shaped dose-response curve (ED50 = 2 ng/ml) with no significant neutrophil chemotactic activity at doses greater than 200 ng/ml. Also, in cytochalasin B-pretreated PMNL, NAP-3 elicited release of myeloperoxidase and beta-glucuronidase. Crossdesensitization studies in PMNL enzyme release revealed crossreactivities with the NAP-1/IL-8-R on PMNL. NAP-3 (MGSA/gro) appears to represent the first member of the novel supergene family of beta-thromboglobulin-like host defense cytokines, which expresses both mitogenic as well as proinflammatory properties at the nanogram level.
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PMID:Lipopolysaccharide-stimulated human monocytes secrete, apart from neutrophil-activating peptide 1/interleukin 8, a second neutrophil-activating protein. NH2-terminal amino acid sequence identity with melanoma growth stimulatory activity. 218 61

The human alveolar macrophage product, enzyme-releasing peptide (ERP), has a molecular mass of 8,000 Da, and releases azurophilic and specific granule constituents from neutrophils. A murine monoclonal anti-ERP antibody (12E10H), previously used to show a lack of antigenic identity between ERP and C5a, interleukin 1, tumor necrosis factor, and gamma-interferon, showed no cross-reactivity with interleukin 8. 12E10H and a fluorescein-labeled second antibody were used to visualize ERP on the macrophage surface. ERP was removed from alveolar macrophages by a 3-min incubation with 5 X 10(-7) M bovine pancreatic trypsin at 37 degrees C. The washed trypsinized cells could readhere to plastic and exclude trypan blue. Dilution of the trypsin-derived ERP released myeloperoxidase from cytochalasin-B-treated neutrophils dose dependently. The enzyme-releasing ability of the trypsin-derived material was removed by immunoprecipitation using antibody 12E10H bound to Staphylococcal protein A Sepharose 4B. The estimated molecular mass of the trypsin-derived ERP (by molecular sieve chromatography on HPLC) was approximately 8,500 Da. Other proteases (plasmin, thrombin, and cathepsin G) also released ERP from the cell surface, but the ERP was not an active secretagogue for neutrophils. However, macrophages cultured with protease inhibitors did not show decreased ERP accumulation in the medium. Our data indicate that ERP exists on the surface of human alveolar macrophages and can be released by proteases found within the lung environment in some disease states.
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PMID:Liberation of a neutrophil enzyme-releasing peptide from the surface of human alveolar macrophages. 236 Jun 46

A synthetic peptide, AVLPRSAKEL (LU10), the N-terminal amino acid sequence of chemotactic protein (LUCT/IL-8), showed chemotactic activity to polymorphonuclear leukocytes (PMN) with an ED50 of 5 nM for comparable to that of LUCT. Native LUCT and LU10 specifically induced the phosphorylation of 64 kD protein of PMN, and serine residue in the 64 kD protein was major phosphorylated amino acid. Furthermore, native LUCT enhanced the release of myeloperoxidase and beta-glucuronidase from PMN in the presence of cytochalasin B and FMLP, but LU10 did not. These results strongly suggest that the active site for both chemotactic stimulation and 64 kD protein phosphorylation is localized on the sequence of N-terminal 10 amino acids of LUCT.
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PMID:Localization of chemotactic activity and 64 kD protein phosphorylation for human polymorphonuclear leukocytes in N-terminus of the chemotactic protein LUCT/IL-8. 267 39

Recent studies have suggested that exposure to air pollutants may sensitise susceptible individuals to allergen. We have investigated the effect of exposure for 6 h to 400 ppb NO2 on nasal airways resistance (NAR) and changes in inflammatory mediators (IMs) in nasal lavage in subjects with a history of seasonal allergic rhinitis. In this single blind crossover study, 8 patients were randomised to exposure to either air or 400 ppb NO2 in air and evaluated for changes in NAR and IM, before and after exposure. Another 8 patients were further challenged with allergen after similar exposure regimes and then evaluated for changes in NAR and IMs. Exposure to air or NO2 did not alter either NAR or the levels of eosinophil cationic protein (ECP), mast cell tryptase (MCT), myeloperoxidase (MPO) or interleukin (IL)-8 in nasal lavage. MCT was significantly increased after allergen challenge following exposure to both air and NO2. In contrast, ECP was significantly increased by allergen challenge only after exposure to NO2. Neither MPO nor IL-8 were altered after allergen challenge. These results suggest that NO2 may increase eosinophil activation in the early-phase response to nasal allergen provocation in allergic rhinitis.
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PMID:Nitrogen dioxide increases eosinophil activation in the early-phase response to nasal allergen provocation. 761 14

Cell-mediated immune reactions are essential to our immune response toward foreign organisms such as microorganisms, or in the response toward foreign tissue Ags, as seen in the rejection of allogeneic transplanted organs. Similar reactions form the basis for the development and the progression of delayed-type hypersensitivity (DTH) reactions. We found that the alpha-chemokine IL-8 plays an important pathophysiologic role for the development of a DTH reaction because infusion of a neutralizing anti-IL-8 mAb (WS-4) was able to suppress the development of a tuberculin skin reaction in rabbits, as judged by histologic, biochemical, and clinical examinations. Thus, the number of neutrophil granulocytes and lymphocytes at the site of tuberculin injection was decreased considerably, and the clinical signs of inflammation were suppressed almost completely at 24 h after intracutaneous injection of tuberculin, as judged by the size of the infiltrates. In contrast, we did not see any effect on the visible erythema of the skin. We found that the tissue content of myeloperoxidase (MPO), reflecting the number of infiltrating neutrophils, was lowered significantly. Furthermore, immunohistochemical analysis confirmed that IL-8 immunoreactivity is actually enhanced in the skin of positive tuberculin reactions. The results indicate that IL-8 plays an important role for the early accumulation of leukocytes in the skin and for the clinical signs of a DTH reaction.
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PMID:The delayed-type hypersensitivity reaction is dependent on IL-8. Inhibition of a tuberculin skin reaction by an anti-IL-8 monoclonal antibody. 763 63

The administration of a high-dose of a serine protease inhibitor is recommended in patients complicated by multiple organ failure (MOF), including adult respiratory distress syndrome (ARDS), induced by acute pancreatitis. The accumulation of polymorphonuclear leukocytes (PMN) in affected organs is considered to be one of the causative factors of MOF. Adhesion to endothelial cells (EC), via adhesion molecules, and the transendothelial migration of PMN is closely associated with the accumulation of PMN. We examined the effects of two serine protease inhibitors, ulinastatin (UT) and gabexate mesilate (GM), on EC-PMN adhesion and transendothelial migration in human umbilical vein EC and 51Cr-labeled PMN in vitro. EC-PMN adhesion, and the expression of intercellular adhesion molecule-1 (ICAM-1) and endothelial cell adhesion molecule-1 (ELAM-1) on EC induced by IL-1 beta and TNF alpha, were reduced by the pretreatment of EC with these inhibitors. The transendothelial migration of PMN stimulated by IL-8 was also inhibited by pretreating PMN with UT or GM. We also examined whether these inhibitors reduced PMN accumulation in the lung in rats with acute pancreatitis induced by a closed duodenal loop. The myeloperoxidase activity in and histological findings of the lung suggested that UT and GM reduced PMN accumulation. In conclusion, serine protease inhibitors may inhibit PMN accumulation in ARDS due to acute pancreatitis.
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PMID:Effects of serine protease inhibitors on accumulation of polymorphonuclear leukocytes in the lung induced by acute pancreatitis in rats. 764 5

Because leukocyte-mediated tissue damage is an important component of the pathologic picture in ischemia/reperfusion, we have sought mechanisms by which PMNs are directed into hypoxic tissue. Incubation of human endothelial cells (ECs) in hypoxia, PO2 approximately 14-18 Torr, led to time-dependent release of IL-8 antigen into the conditioned medium; this was accompanied by increased chemotactic activity for PMNs, blocked by antibody to IL-8. Production of IL-8 by hypoxic ECs occurred concomitantly with both increased levels of IL-8 mRNA, based on polymerase chain reaction analysis, and increased IL-8 transcription, based on nuclear run-on assays. Northern analysis of mRNA from hypoxic ECs also demonstrated increased levels of mRNA for macrophage chemotactic protein-1, another member of the chemokine superfamily of proinflammatory cytokines. IL-8 gene induction was associated with the presence of increased binding activity in nuclear extracts from hypoxic ECs for the NF-kB site. Studies with human umbilical vein segments exposed to hypoxia also demonstrated increased elaboration of IL-8 antigen compared with normoxic controls. In mice exposed to hypoxia (PO2 approximately 30-40 Torr), there was increased pulmonary leukostasis, as evidenced by increased myeloperoxidase activity in tissue homogenates. In parallel, increased levels of transcripts for IP-10, a murine homologue in the chemokine family related to IL-8, were observed in hypoxic lung tissue. Taken together, these data suggest that hypoxia constitutes a stimulus for leukocyte chemotaxis and tissue leukostasis.
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PMID:Hypoxic induction of interleukin-8 gene expression in human endothelial cells. 816 58


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