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Query: UNIPROT:P10145 (
IL-8
)
23,849
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Polymorphonuclear neutrophils (PMN) have been implicated in the pathogenesis of emphysema. The chemokines interleukin-8(
IL-8
), growth-related oncogene (GRO-alpha) and extractable nuclear antigen (ENA)-78 may be involved in the increased numbers of PMN in smokers' airspaces. The levels of these cytokines in bronchoalveolar lavage fluid (BALF) and bronchoalveolar lavage leukocyte conditioned medium (LCM), along with BALF PMN numbers in 12 smokers who abstained for 12 h (chronic smoking) or continued to smoke until I h before study (acute smoking) and seven nonsmokers were compared. Neutrophils in BALF increased in acute (1.96+/-0.53%, 0.99+/-0.32x10(6) cells) compared with chronic smokers (0.59+/-0.25%, 0.61+/-0.24x10(6) cells, p<0.05 nonsmokers) and nonsmokers (0.79+/-0.29%, 0.05+/-0.01x 10(6) cells, p<0.05). There were no differences in
IL-8
or GRO-alpha in BALF between smokers and nonsmokers.
ENA-78
levels were lower in smokers (p=0.006). There was no difference in
IL-8
, GRO-alpha or
ENA-78
in LCM from unstimulated cells in smokers versus nonsmokers. After stimulation with lipopolysaccharide (LPS) 10 ng mL(-1),
IL-8
release in acute smokers (p=0.04) and GRO-alpha release in smokers (p=0.009) were significantly higher than in nonsmokers. Following stimulation with LPS 100 ng.mL(-1), GRO-alpha release was higher in smokers (p=0.03) and increased further in acute smokers (p=0.02 versus nonsmokers, p=0.04 versus chronic smokers) and
ENA-78
release increased in smokers (p=0.02 versus non-smokers). In conclusion, influx of polymorphonuclear neutrophils into smokers' airspaces is an acute phenomenon and neutrophil chemokine release from mixed bronchoalveolar lavage leukocytes is influenced by cigarette smoking and endotoxins.
...
PMID:Neutrophil chemokines in bronchoalveolar lavage fluid and leukocyte-conditioned medium from nonsmokers and smokers. 986 98
Neutrophils (polymorphonuclear neutrophils; PMN) and a redundant system of chemotactic cytokines (chemokines) have been implicated in the pathogenesis of the acute respiratory distress syndrome in patients with sepsis. PMN express two cell surface receptors for the CXC chemokines, CXCR1 and CXCR2. We investigated the expression and function of these receptors in patients with severe sepsis. Compared with normal donors, CXCR2 surface expression was down-regulated by 50% on PMN from septic patients (p < 0.005), while CXCR1 expression persisted. In vitro migratory responses to the CXCR1 ligand,
IL-8
, were similar in PMN from septic patients and normal donors. By contrast, the migratory response to the CXCR2 ligands, epithelial cell-derived neutrophil activator (
ENA-78
) and the growth-related oncogene proteins, was markedly suppressed in PMN from septic patients (p < 0.05). Ab specific for CXCR1 blocked in vitro migration of PMN from septic patients to
IL-8
(p < 0.05), but not to FMLP. Thus, functionally significant down-regulation of CXCR2 occurs on PMN in septic patients. We conclude that in a complex milieu of multiple CXC chemokines, CXCR1 functions as the single dominant CXC chemokine receptor in patients with sepsis. These observations offer a potential strategy for attenuating adverse inflammation in sepsis while preserving host defenses mediated by bacteria-derived peptides such as FMLP.
...
PMID:Expression and function of the chemokine receptors CXCR1 and CXCR2 in sepsis. 997 13
GROalpha, an autocrine mitogenic factor for melanoma cell lines, belongs to the superfamily of alpha-chemokines. Here, we report that GROalpha stimulates the growth of human umbilical vein endothelial cells (HUVEC) in vitro, with proliferation being significantly stimulated by 100 nM recombinant human (rh) GROalpha. Proliferation was significantly inhibited by 100 microg/ml anti- human GROalpha monoclonal antibody (mAb), while excess GROalpha restored the growth. The addition of rhIL-8, rhIP-10, anti-human
IL-8
or anti-human
ENA-78
mAbs did not alter HUVEC proliferation. [125I]
IL-8
binding to HUVEC was saturable and inhibited by non-radioactively iodinated
IL-8
, but not non-iodinated
IL-8
. [125I]GROalpha binding was also inhibited by iodinated
IL-8
. Since these data suggested specific binding sites for alpha-chemokines on HUVEC, we tested the effect of antileukinate, a potent alpha-chemokine receptor inhibitor, on [125I]GROalpha binding. Antileukinate inhibited GROalpha binding and suppressed HUVEC proliferation in a dose-dependent manner. Antileukinate was not cytotoxic, with no decrease in cell viability in the presence of 100 microM antileukinate. These findings suggest that GROalpha is essential for HUVEC growth factor and that antileukinate inhibits growth by preventing autocrine GROalpha receptor binding. This raises the interesting possibility of alpha-chemokine receptor inhibitors, such as antileukinate, in the treatment of cancer where angiogenesis is an important factor for tumour growth.
...
PMID:Inhibition of GROalpha-induced human endothelial cell proliferation by the alpha-chemokine inhibitor antileukinate. 1020 71
A physical map of the CXC chemokine locus on chromosome 4 has been constructed by PCR analysis and PFGE mapping of YAC clones. The genes for
IL8
, GRO1, PPBP, PF4,
SCYB5
(
ENA-78
) and SCYB6 (GCP-2) have been co-localized on a 335-kb genomic fragment. The GRO2 and GRO3 genes did not map within this region and based on analysis of a YAC contig overlapping
IL8
we speculate that GRO2 and GRO3 map downstream of this region. We have also assigned the novel CXC chemokine gene, SCYB9B (alias H174/betaR1) to chromosome 4q21, upstream and within 12 kb of INP10. Like INP10 and MIG, INP10 and SCYB9B are arranged in a head to tail manner. The chromosomal arrangement of these genes appears to reflect the evolution of this multigene family and supports the theory that it arose by gene duplication.
...
PMID:Physical mapping of the CXC chemokine locus on human chromosome 4. 1034 98
Ulcerative colitis and Crohn's disease are characterized by chronic intestinal inflammation. Intestinal bacteria initiate the activation of intestinal inflammatory processes, which are mediated by proinflammatory cytokines and chemokines. In inflammatory bowel disease, intestinal inflammation is not downregulated, in part due to defective or absent inhibitory processes. Studies to date have demonstrated that
IL-8
, MCP-1, and
ENA-78
are highly expressed in the intestinal mucosa in areas of active Crohn's disease and ulcerative colitis. Neutrophils and macrophages in the inflamed intestine synthesize and secrete large amounts of chemokines in patients with inflammatory bowel disease. Increased chemokine expression has also been observed in epithelial cells, endothelial cells, and smooth muscle cells. Future trials of specific agents capable of inhibiting chemokine synthesis and secretion or blocking chemokine-chemokine receptor interaction will be important to study in patients with ulcerative colitis and Crohn's disease.
...
PMID:Chemokines in the inflammatory bowel diseases. 1053 2
In the present study, the sensitivity of LMVEC and human umbilical vein endothelial cells (HUVEC) to lipopolysaccharide (LPS) and the proinflammatory cytokines IL-1, tumour necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma) was compared. To this end, the production of the CC- (MCP-1), CXC- (
IL-8
,
ENA-78
, Groalpha, NAP-2, GCP-2) and CX3C (fractalkine) chemokines was studied. A low basal production of these chemokines was observed in both cell types. TNF-alpha, IL-1 and LPS up-regulated all chemokines tested. IFN-gamma however was only able to up-regulate MCP-1 production. LMVEC were more sensitive to IL-1 and LPS compared with HUVEC, since LMVEC produced significantly more MCP-1,
ENA-78
and Groalpha (P < 0. 01) under these conditions. Maximal production of MCP-1 in LMVEC was achieved with TNF-alpha (28.4 ng/ml, P < 0.01), whereas IL-1 was the most potent stimulator of
ENA-78
(2.78 ng/ml, P < 0.001) and Groalpha (29.2 ng/ml, P < 0.001).
IL-8
production in LMVEC cells was maximal after LPS stimulation (28.4 ng/ml), but lower than on HUVEC (P < 0.01). LPS, TNF-alpha and IL-1 stimulation strongly up-regulated all chemokine mRNA. No quantitative differences in mRNA expression between LMVEC and HUVEC were detected for MCP-1 and Groalpha after LPS stimulation. mRNA expression of
ENA-78
, GCP-2, CX3C and NAP-2 was however higher in LMVEC under LPS stimulation. In contrast,
IL-8
mRNA was slightly more expressed in HUVEC under these conditions. These results further support the hypothesis that the microvascular lung endothelium plays an active role in the induction and perpetuation of acute lung injury.
...
PMID:Release of CXC-chemokines by human lung microvascular endothelial cells (LMVEC) compared with macrovascular umbilical vein endothelial cells. 1054 Jan 94
In upper urinary tract infections, tubular epithelial cells (TEC) may play a pivotal role in the initiation of the renal inflammatory response. They exert crucial immunological functions such as processing and presentation of foreign antigen, secretion of proinflammatory cytokines (interleukin-6 [IL-6] and tumor necrosis factor alpha) and chemokines (
IL-8
, MCP-1,
ENA-78
, and RANTES). Since monolayer cultures are a limited model for polarized tubular epithelial cells, we studied the side-dependent
IL-8
secretion of TEC by using cell culture inserts as a basement membrane imitation. Primary cultures of proximal TEC were stimulated with differently fimbriated mutants of Escherichia coli, E. coli LPS, S-fimbria isolates, and IL-1alpha.
IL-8
protein was measured by enzyme-linked immunosorbent assay, and
IL-8
-like biological activity was tested by measuring elastase release from polymorphonuclear cells in supernatants of the upper and lower compartments.
IL-8
mRNA was compared by competitive PCR.
IL-8
secretion by TEC into the basolateral environment was significantly higher than secretion into the apical compartment, representing the tubular lumen. However, stimulation of
IL-8
secretion by TEC was restricted to IL-1alpha and was not inducible by E. coli mutants, S fimbriae, or lipopolysaccharide. With this in vitro model of polarized TEC, we show that luminal contact of TEC with uropathogenic E. coli does not result in enhanced
IL-8
secretion. The basolaterally directed production of the neutrophil chemotactic factor
IL-8
by TEC after stimulation with IL-1alpha might play an important role in the initiation of inflammatory cell influx into the renal parenchyma.
...
PMID:Interleukin-8 secretion of cortical tubular epithelial cells is directed to the basolateral environment and is not enhanced by apical exposure to Escherichia coli. 1060 5
ORF-74, a 7TM receptor oncogene encoded by human herpes virus 8, shows 50% constitutive activity in stimulating phosphatidylinositol turnover and binds a large variety of CXC chemokines. These endogenous ligands cover a full spectrum of pharmacological properties with growth-related oncogene (GRO)-alpha and -gamma functioning as full agonists; GRObeta as a partial agonist; interleukin (IL)-8, neutrophil-activating peptide (NAP)-2, and epithelial cell-derived activating peptide (ENA)-78 as neutral ligands; granulocyte colony-stimulating factor (GCP)-2 as a partial inverse agonist; and interferon-gamma inducible protein (IP)-10 and stromal cell-derived factor (SDF)-1alpha as full inverse agonists. The affinity for the agonists was independent of whether it was determined in competition binding against the agonist (125)I-GROalpha, against the inverse agonist (125)I-IP-10, or against the neutral ligand (125)I-
IL-8
. Similarly, the affinities of the inverse agonists were within 1 order of magnitude independent of the choice of radioligand. In contrast, the neutral ligands
IL-8
, NAP-2, and
ENA-78
, which all displaced (125)I-
IL-8
with single-digit nanomolar affinity showed up to 1000-fold lower affinity against both the radioactive agonist and against the radioactive inverse agonist. A close correlation was observed between the EC(50) values for the ligands and their IC(50) values measured against either radioactive agonist or radioactive inverse agonist, but a poor correlation was found to the IC(50) value measured against the neutral ligand. It is concluded that in ORF-74, ligands compete for binding more according to pharmacological property than to structural homology and that both agonists and inverse agonists, in contrast to neutral ligands, apparently bind with high affinity either to a common conformation of the receptor or to readily interconvertible states, not available for the neutral ligands.
...
PMID:Potency of ligands correlates with affinity measured against agonist and inverse agonists but not against neutral ligand in constitutively active chemokine receptor. 1069 2
Neutrophils migrate through endothelium using an ordered sequence of adhesive interactions and activating signals. To investigate the consequences of disruption of this sequence, we characterized adhesion and migration of neutrophils perfused over HUVEC that had been treated with TNF-alpha for 4 h and evaluated changes caused by exogenously added chemotactic agents. When HUVEC were treated with 2 U/ml TNF, flowing neutrophils adhered, with the majority rolling and relatively few migrating through the monolayer. If fMLP,
IL-8
, zymosan-activated plasma (a source of activated complement factor C5a), epithelial cell-derived neutrophil-activating peptide (
ENA-78
), or growth-regulating oncogene, GRO-alpha, was perfused over these neutrophils, they stopped rolling and rapidly migrated over the monolayer, but did not penetrate it. When HUVEC were treated with 100 U/ml TNF, the majority of adherent neutrophils transmigrated. If neutrophils were treated with fMLP,
IL-8
, C5a,
ENA-78
, or GRO-alpha just before perfusion over this HUVEC, transmigration, but not adhesion, was abolished. However, when platelet-activating factor was used to activate neutrophils, migration through HUVEC treated with 100 U/ml TNF was not impaired, and migration through HUVEC treated with 2 U/ml TNF was actually increased. Transmigration required ligation of CXC chemokine receptor-2 on neutrophils, and differential desensitization of this receptor (e.g., by fMLP but not platelet-activating factor) may explain the pattern of disruption of migration. Thus, transmigration may require presentation of the correct activators in the correct sequence, and inappropriate activation (e.g., by systemic activators) could cause pathological accumulation of neutrophils in the vessel lumen.
...
PMID:Differential ability of exogenous chemotactic agents to disrupt transendothelial migration of flowing neutrophils. 1082 Feb 79
CXC chemokines are chemotactic cytokines that specifically act on neutrophils. To obtain insight into the extent of local production of CXC chemokines during acute pyelonephritis, interleukin (IL)-8, growth-related oncogene (GRO)-alpha, and epithelial cell-derived neutrophil-activating protein (ENA)-78 were measured in urine and plasma samples from patients with culture-proven urosepsis (n=33), healthy human control subjects with sterile urine (n=31), and human volunteers intravenously injected with endotoxin (n=11). Patients had profoundly elevated urine concentrations of chemokines with no (GRO-alpha and
ENA-78
) or little (
IL-8
) elevation in plasma. Endotoxin-challenged subjects demonstrated transient increases in plasma chemokine concentrations, with no (GRO-alpha) or little (
IL-8
and
ENA-78
) elevation in urine. Urine from patients exerted chemotactic activity toward neutrophils, which was partially inhibited by neutralizing antibodies against
IL-8
, GRO-alpha, or
ENA-78
. During urosepsis, CXC chemokines are predominantly produced within the urinary tract, where they are involved in the recruitment of neutrophils to the urinary compartment.
...
PMID:Chemotactic activity of CXC chemokines interleukin-8, growth-related oncogene-alpha, and epithelial cell-derived neutrophil-activating protein-78 in urine of patients with urosepsis. 1106 46
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