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)

The epidemic form of the hemolytic uremic syndrome (HUS) has been associated with a verocytotoxin producing Escherichia coli infection. Endothelial cell damage of glomeruli and arterioles of the kidney plays a central role in the pathogenesis of HUS. A number of observations in vivo and in vitro indicate that inflammatory mediators contribute to this process. In this study we investigated the binding of 125I-verocytotoxin-1 (VT-1) to freshly isolated human nonadherent monocytes as well as the nature of the ligand to which VT-1 binds on monocytes. On the average, freshly isolated monocytes have 0.07 x 10(5) specific binding sites for 125I-VT-1 per cell. Preincubation of nonadherent monocytes with bacterial lipopolysaccharide (LPS) caused a 23- to 30-fold increase of specific binding sites for VT-1 as shown by Scatchard plot analysis. Thin-layer chromatography of extracted neutral glycolipids of the cells and subsequent binding of 125I-VT-1 showed that human monocytes bind VT-1 to a globotriaosylceramide (Gb3) species that is different from that found on endothelial cells, probably a short-chain fatty acyl Gb3 or an alpha-OH-Gb3. In addition, we evaluated the functional consequences of VT-1 binding to human monocytes by investigating the effects of VT-1 on the total protein synthesis and, specifically, the production of the cytokines interleukin-1 beta (IL-1 beta), tumor necrosis factor-alpha (TNF-alpha), IL-6, and IL-8. We observed that VT-1 did not inhibit overall protein synthesis, nor under basal conditions, neither after stimulation with LPS, in contrast to previous observations with endothelial cells. Furthermore, we found that VT-1 induces the synthesis of the cytokines IL-1 beta, TNF-alpha, IL-6, and IL-8 in nonstimulated monocytes by a LPS-independent cell activation. The increase in the production of cytokines was parallelled by an increase in mRNA, as was demonstrated for IL-6 by reverse transcription-polymerase chain reaction. These data suggest that inflammatory mediators locally produced by VT-1-stimulated monocytes may contribute to the pathogenic mechanism of the HUS.
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PMID:Effects of verocytotoxin-1 on nonadherent human monocytes: binding characteristics, protein synthesis, and induction of cytokine release. 870 72

The epidemic form of the hemolytic uremic syndrome (HUS) in children is hallmarked by endothelial cell damage, most predominantly displayed by the glomerular capillaries. The influx of mononuclear (MO) and polymorphonuclear cells (PMNs) into the glomeruli may be an important event in the initiation, prolongation, and progression of glomerular endothelial cell damage in HUS patients. The molecular mechanisms for the recruitment of these leukocytes into the kidney are unclear, but monocyte chemoattractant protein-1 (MCP-1) and IL-8 are suggested to be prime candidates. In this study, we analyzed the presence of both chemokines in 24-h urinary (n = 15) and serum (n = 14) samples of HUS children by specific ELISAs. Furthermore, kidney biopsies of three different HUS children were examined for MO and PMN cell infiltration by histochemical techniques and electron microscopy. Whereas the chemokines MCP-1 and IL-8 were present in only very limited amounts in urine of 17 normal control subjects, serial samples of HUS patients demonstrated significantly elevated levels of both chemokines. HUS children with anuria showed higher initial and maximum chemokine levels than their counterparts without anuria. A strong positive correlation was observed between urinary MCP-1 and IL-8 levels. Whereas initial serum IL-8 levels were significantly increased in HUS children, serum MCP-1 levels were only slightly elevated compared with serum MCP-1 in control children. No correlation was found between urinary and serum chemokine concentrations. Histologic and EM studies of HUS biopsy specimens clearly showed the presence of MOs and to a lesser extent of PMNs in the glomeruli. The present data suggest an important local role for MOs and PMNs in the process of glomerular endothelial-cell damage. The chemokines MCP-1 and IL-8 may possibly be implicated in the pathogenesis of HUS through the recruitment and activation of MOs and PMNs, respectively.
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PMID:Monocyte chemoattractant protein-1 and interleukin-8 levels in urine and serum of patents with hemolytic uremic syndrome. 962 85

The hemolytic uremic syndrome is an important cause of acute renal failure and leads to substantial morbidity and mortality. In pediatric patients, the hemolytic uremic syndrome usually follows hemorrhagic colitis caused by verocytotoxin-producing Escherichia coli. Several well-publicized outbreaks of hemorrhagic colitis and hemolytic uremic syndrome have highlighted the morbidity and mortality of infection with verocytotoxin-producing Escherichia coli. Recent studies have further demonstrated the role of verocytotoxins in mediating renal cell injury and the mechanisms of verocytotoxin cell injury. Although the endothelial cell appears to be the major target of verocytotoxin-mediated cell injury, studies have also shown that mesangial cells, renal tubular epithelial cells, monocytes and cells derived from the monocytic cell line are also targets of verocytotoxin-mediated biological effects. It has also been shown that inflammatory cytokines are likely to play an important role in hemolytic uremic syndrome. Serum levels of IL-8 and TNF-alpha are elevated in hemolytic uremic syndrome and verocytotoxins promote the generation of inflammatory cytokines from monocytes and monocyte-derived cell lines. These new findings have important implications for current therapy and potential future therapy of hemolytic uremic syndrome.
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PMID:The pathophysiology of the hemolytic uremic syndrome. 1049 41

Experimental data suggest that the host's inflammatory response is involved in the pathophysiology of verotoxin-producing Escherichia coli (VTEC)-associated hemolytic uremic syndrome (HUS). We compared the circulating levels of pro- [interleukin (IL)-6, IL-8] and anti-inflammatory [IL-10 and IL-1 receptor antagonist (Ra)] mediators on enrollment among children with HUS due to E. coli O157:H7, according to the severity of renal dysfunction. The latter was evaluated by the occurrence of oligoanuria, the requirement for dialysis, and a glomerular filtration rate (GFR) </=80 ml/min per 1. 73 m(2) measured 1 year later. Increased levels of IL-6 (P<0.0001), IL-10 (P<0.0001), and IL-1Ra (P<0.07) were found among patients with HUS compared with normal controls. Children with severe renal dysfunction also had tenfold increased levels of IL-6 and higher concentrations of IL-10 and IL-1Ra. Both the IL-6/IL-10 (4.9+/-8.3 vs. 0.5+/-0.4, P=0.01) and the IL-6/IL-1Ra ratios (0.10+/-0.20 vs. 0. 01+/-0.01, P=0.04) were significantly increased. GFR correlated well with IL-6 levels, IL-6/IL-10 and IL-6/IL-1Ra ratios. Our data demonstrate that the inflammatory response of the host is associated with the severity of renal dysfunction during classic HUS. An imbalance between the pro- and the anti-inflammatory responses may be involved in the pathophysiology of VTEC-associated HUS.
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PMID:Circulating inflammatory cytokine levels in hemolytic uremic syndrome. 1060 33

The objective of this study was to identify parameters indicating a risk for developing typical haemolytic uremic syndrome (D+HUS) during the prodromal phase of diarrhea caused by enterohaemorrhagic Escherichia coli (EHEC). Forty-eight children were studied prospectively with regard to inflammatory serum factors on admission to hospital. Ten patients developed D+HUS (group I), 15 suffered from viral-gastroenteritis (group IIa) and 23 from other types of bacterial gastroenteritis (group IIb). Mean levels of IL-8 tended to be elevated in group I compared to groups IIa and IIb. Neopterin and IL-10 levels particularly were significantly decreased in HUS in comparison to both gastroenteritis groups. Low IL-10 levels indicate a substantial disregulation of the immune response in HUS, as IL-10 downregulates the pro-inflammatory response and suppresses pro-coagulant activity in experimental endotoxemia. Our results suggest low neopterin, high IL-8 and especially low IL-10 levels are indicators of a high risk for developing HUS.
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PMID:Inflammatory and immunological parameters in children with haemolytic uremic syndrome (HUS) and gastroenteritis-pathophysiological and diagnostic clues. 1084 73

Shiga toxin (Stx) and lipopolysaccharide (LPS) both participate in the pathogenesis of post-diarrheal hemolytic uremic syndrome (HUS), yet little is known about the factors that modulate the host response to these toxins. We have previously shown that the baboon develops HUS if 100 ng/kg of purified Stx-1 is administered rapidly as a single bolus, but not if it is given as four 25-ng/kg doses every 12 h. We therefore used this baboon model to study the response to small intravenous doses of Stx-1, with and without the co-administration of LPS. The co-administration of two 1-mg/kg doses of LPS (given at 0 and 24 h) and four 25-ng/kg doses of Stx-1 (given at 0, 12, 24, and 36 h) resulted in HUS, but the administration of either toxin separately did not. The development of HUS was associated with a rise in urinary, but not plasma concentrations of TNF, and a rise in both urinary and plasma concentrations of IL-6 and IL-8. We speculate that LPS is not required for disease expression in the human, but that it can augment the response to otherwise subtoxic amounts of Stx and this augmentation may be mediated by LPS-induced cytokine release.
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PMID:Response to Shiga toxin-1, with and without lipopolysaccharide, in a primate model of hemolytic uremic syndrome. 1168 8

Shiga toxins(Stxs), which are produced by enterohemorrhagic Escherichia coli and Shigella dysenteriae serotype I, induce proinflammatory cytokines including tumor necrosis factor-alpha, interleukin(IL)-1 beta, IL-6, interferon-gamma, and chemokines such as IL-8 in intestinal epithelial cells, vascular endothelial cells, and monocytes/macrophages in vitro and in kidneys and spleen in vivo. Cytokines induced by Stxs and lipopolysaccharide enhance the toxicity of Stxs via up-regulation of the expression of Gb3, a Stx receptor, and infiltration of neutrophils. Stxs bind to neutrophils and transmigrate across intestinal mucosa and are transported to the target organs through bloodstreams. Stxs induce cytokines in vascular endothelial cells and peripheral blood monocytes and may injure organ tissues, finally resulting in hemolytic uremic syndrome and encephalopathia.
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PMID:[Effect of cytokines on the expression of Shiga toxin toxicity]. 1207 78

Shiga toxin (Stx)-producing Escherichia coli (STEC) is associated with hemolytic uremic syndrome (HUS). High inflammatory cytokine [interleukin (IL)-6 and IL-8] levels and low anti-inflammatory cytokine (IL-10) levels are indicators of a high risk for developing HUS in STEC-infected children. In this study, we investigated inhibitory action of telithromycin, a ketolide, against STEC and against Stx and lipopolysaccharide (LPS). Telithromycin inhibited in vitro STEC growth without inducing Stx phage, in marked contrast to norfloxacin. Stx markedly induced inflammatory (but not anti-inflammatory) cytokine production in human peripheral blood monocytes, while LPS induced both inflammatory and anti-inflammatory cytokine production. Telithromycin selectively inhibited the IL-6 and IL-8 production from Stx-stimulated (but not LPS-stimulated) monocytes. The drug did not significantly inhibit IL-10 production. Our data suggest that Stx plays a crucial role in the stimulation of inflammatory cytokines and such inflammatory response is inhibited by telithromycin, an anti-bacterial agent.
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PMID:Inhibitory action of telithromycin against Shiga toxin and endotoxin. 1455 42

Infection with Shiga toxin (Stx)-producing Escherichia coli can lead to development of hemolytic uremic syndrome (HUS). Patients with severe HUS often exhibit central nervous system (CNS) pathology, which is thought to involve damage to brain endothelium, a component of the blood-brain barrier. We hypothesized that this neuropathology occurs when cerebral endothelial cells of the blood-brain barrier, sensitized by exogenous TNF-alpha and stimulated by Stx1, produce and release proinflammatory cytokines. This was tested by measuring changes in cytokine mRNA and protein expression in human brain endothelial cells (hBEC) in vitro when challenged by TNF-alpha and/or Stx. High doses of Stx1 alone were somewhat cytotoxic to hBEC; Stx1-treated cells produced increased amounts of IL-6 mRNA and secreted this cytokine. IL-1beta and TNF-alpha mRNA, but not protein, were increased, and IL-8 secretion increased without an observed increase in mRNA. Cells pretreated with TNF-alpha were more sensitive to Stx1, displaying greater Stx1-induction of mRNA for TNF-alpha, IL-1beta, and IL-6, and secretion of IL-6 and IL-8. These observations suggest that in the pathogenesis of HUS, Stx can induce cytokine release from hBEC, which may contribute toward the characteristic CNS neuropathology.
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PMID:Escherichia coli Shiga toxin 1 and TNF-alpha induce cytokine release by human cerebral microvascular endothelial cells. 1500 Dec 24

Cattle are a major reservoir of Escherichia coli 0157:H7, an important zoonotic pathogen that causes hemorrhagic colitis and hemolytic uremic syndrome (HUS). Colonization of cattle occurs predominantly in the large intestine, and may especially target follicle-associated epithelium (FAE) in the terminal rectum. Bacterial colonization involves induction of attaching-effacing (A/E) lesions, mediated by type III secreted proteins and an outer membrane protein called intimin. ToxB, encoded on plasmid pO157, contributes to adherence of E. coli O157:H7 through promotion of the production and/or secretion of type III secreted proteins. Production of type III secreted proteins and intestinal colonization appear to involve quorum-sensing mechanisms. In the human host, E. coli O157:H7 may have a preference for FAE in the distal small intestine. The H7 flagellum induces production of chemokines such as interleukin 8, and neutrophilic infiltration of the intestinal mucosa, which in turn may enhance Shiga toxin (Stx) uptake across the intestinal epithelium. Both Stx and cytokine responses play critical roles in the induction of the vascular lesions that underlie hemorrhagic colitis and HUS. In cattle, Stx binds to intestinal crypt cells and submucosal lymphocytes but not vascular endothelium. The role played by Stx in cattle may be to suppress mucosal immunity, yet enhance other effects that promote intestinal colonization.
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PMID:Escherichia coli 0157:H7: an update on intestinal colonization and virulence mechanisms. 1546 May 38


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