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 cytokine neutrophil-activating peptide-1/interleukin-8 (NAP/IL-8) activates neutrophils (PMN) and elicits selective diapedesis of PMN into the extracellular space. The glomerular mesangial cell (MC) is a specialized pericyte that controls glomerular filtration and synthesizes and responds to a variety of cytokines. Because of its location within the glomerulus, the MC is in a pivotal position to orchestrate events underlying immune injury. Since immune-injured glomeruli have been shown to produce NAP/IL-8 activity in vitro, we assessed whether lipopolysaccharide (LPS)- or cytokine-activated MC might be a source of this activity. Pure human MC, devoid of monocyte/macrophage and fibroblast contamination, were grown by explant from collagenase-treated glomeruli. Human recombinant interleukin-1 alpha (IL-1 alpha, 20 ng/ml), IL-1 beta (50 ng/ml), tumor necrosis factor alpha (TNF, 100 ng/ml) and lipopolysaccharide (LPS, 10 micrograms/ml) stimulated release of a neutrophil chemotactic factor from cultured MC. Both concentrated (fivefold) and unconcentrated MC supernatants stimulated directed neutrophil migration under agarose at a level similar to that of the bacterial chemotactic factor, FMLP. In contrast, unstimulated MC-conditioned media and IL-1 alpha, IL-1 beta. TNF and LPS in medium alone did not directly induce PMN migration. Molecular sizing studies using sequential membrane ultrafiltration identified significant TNF-stimulated, MC-derived chemotactic activity in the 3000 to 10000 kD fraction. An anti-NAP/IL-8 monoclonal antibody, 46E5, significantly inhibited PMN chemotaxis stimulated by TNF-stimulated, MC-conditioned media in a dose-dependent manner.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Cytokine- and LPS-induced synthesis of interleukin-8 from human mesangial cells. 189 76

Previous studies have suggested that epidermal-derived interleukin-1 is involved in the pathogenesis of cutaneous T-cell lymphoma (CTCL); however, the findings are conflicting and studies that combine immunohistochemistry and functional activity have not been performed. We investigated the interleukin-1 level in epidermis of patients with cutaneous T-cell lymphoma using both immunohistochemistry, enzyme-linked immunosorbent assays, and the thymocyte co-stimulation assay. Using supernatants obtained from epidermal cell cultures, we found a significant but small increase of interleukin 1 alpha protein release from involved CTCL epidermis compared to normal epidermis from healthy individuals. Both keratinocytes and leukocytes could release interleukin-1 alpha, but the majority was derived from the keratinocytes. Interleukin-1 beta protein was not detectable. In the thymocyte assay, interleukin-1 alpha was found to be biologically active. When lymphokines derived from a T-cell clone obtained from involved CTCL skin were co-cultured with epidermal cells, an enhanced release of epidermal interleukin-1 alpha could be demonstrated. Because interleukin 1 alpha was increased, we investigated the presence of interleukin 1-inducible keratinocyte-derived interleukin 8 and found it increased in CTCL epidermis compared to normal epidermis from healthy individuals. This study demonstrated an elevated epidermal IL-1 alpha level and IL-8 immunoreactivity in CTCL epidermis, which suggests that this elevated level is induced by lymphokines released from activated T cells.
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PMID:Epidermal interleukin 1 alpha functional activity and interleukin 8 immunoreactivity are increased in patients with cutaneous T-cell lymphoma. 140 10

Human mesangial cells (MC) in culture, when stimulated by interleukin 1 alpha(IL-1 alpha) or tumour necrosis factor (TNF alpha), but not with lipopolysaccharide (LPS), express interleukin 8 (IL-8) mRNA, and both cell associated and extracellular IL-8. Dexamethasone treatment of mesangial cells induced partial inhibition of the release of extracellular IL-8, while cell-associated IL-8 and IL-8 mRNA were not significantly altered. We propose that the mesangial cell has a direct role in the initiation and propagation of inflammatory events within the glomerulus via the generation of the chemotactic cytokine IL-8.
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PMID:Cytokine-activated human mesangial cells generate the neutrophil chemoattractant, interleukin 8. 192 Nov 60

Interleukin-1 (IL-1) and tumour necrosis factor-alpha (TNF-alpha) both induce polymorphonuclear leucocyte (PMNL) infiltration into tissues and they have a synergistic action in this respect. We and others have observed that IL-1 alpha and TNF-alpha induce 51Cr-labelled PMNL migration across monolayers of umbilical vein endothelium via an endothelial cell-dependent mechanism. Here we investigated the interaction of PMNL with fibroblasts, since PMNL probably encounter such cells in many tissues once they traverse the vascular wall. TNF-alpha, but not IL-1 alpha, was found to activate fibroblast monolayers, grown on polycarbonate filters, to stimulate PMNL transfibroblast migration. This was a time- and fibroblast-dependent process which required fibroblast protein synthesis, as indicated by inhibition with cycloheximide. The effect of TNF-alpha was not related to fibroblast chemotactic factor production (primarily IL-8), or to ICAM-1 up-regulation, since IL-1 was as active as TNF-alpha in this respect, without activating fibroblasts to support PMNL transfibroblast migration. Antiserum to IL-8, present during the assay, did not inhibit PMNL migration across the monolayers. The PMNL migration was highly dependent on the function of both CD11a (LFA-1) and CD11b (MAC-1) PMNL adhesion molecules, since monoclonal antibodies to either inhibited migration by about 80%. The results suggest a distinct activation by TNF-alpha of fibroblasts to facilitate PMNL migration through fibroblast barriers. These findings may in part account for the synergistic action of IL-1 and TNF-alpha in inducing extravascular accumulation of PMNL during inflammation.
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PMID:Tumour necrosis factor-alpha but not interleukin-1 induces polymorphonuclear leucocyte migration through fibroblast layers by a fibroblast-dependent mechanism. 193 64

In the present study we demonstrate that human monocytes activated by lipopolysaccharides (LPS) were able to produce high levels of interleukin 10 (IL-10), previously designated cytokine synthesis inhibitory factor (CSIF), in a dose dependent fashion. IL-10 was detectable 7 h after activation of the monocytes and maximal levels of IL-10 production were observed after 24-48 h. These kinetics indicated that the production of IL-10 by human monocytes was relatively late as compared to the production of IL-1 alpha, IL-1 beta, IL-6, IL-8, tumor necrosis factor alpha (TNF alpha), and granulocyte colony-stimulating factor (G-CSF), which were all secreted at high levels 4-8 h after activation. The production of IL-10 by LPS activated monocytes was, similar to that of IL-1 alpha, IL-1 beta, IL-6, IL-8, TNF alpha, granulocyte-macrophage colony-stimulating factor (GM-CSF), and G-CSF, inhibited by IL-4. Furthermore we demonstrate here that IL-10, added to monocytes, activated by interferon gamma (IFN-gamma), LPS, or combinations of LPS and IFN-gamma at the onset of the cultures, strongly inhibited the production of IL-1 alpha, IL-1 beta, IL-6, IL-8, TNF alpha, GM-CSF, and G-CSF at the transcriptional level. Viral-IL-10, which has similar biological activities on human cells, also inhibited the production of TNF alpha and GM-CSF by monocytes following LPS activation. Activation of monocytes by LPS in the presence of neutralizing anti-IL-10 monoclonal antibodies resulted in the production of higher amounts of cytokines relative to LPS treatment alone, indicating that endogenously produced IL-10 inhibited the production of IL-1 alpha, IL-1 beta, IL-6, IL-8, TNF alpha, GM-CSF, and G-CSF. In addition, IL-10 had autoregulatory effects since it strongly inhibited IL-10 mRNA synthesis in LPS activated monocytes. Furthermore, endogenously produced IL-10 was found to be responsible for the reduction in class II major histocompatibility complex (MHC) expression following activation of monocytes with LPS. Taken together our results indicate that IL-10 has important regulatory effects on immunological and inflammatory responses because of its capacity to downregulate class II MHC expression and to inhibit the production of proinflammatory cytokines by monocytes.
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PMID:Interleukin 10(IL-10) inhibits cytokine synthesis by human monocytes: an autoregulatory role of IL-10 produced by monocytes. 194 Jul 99

Interleukin-8 (IL-8), a cytokine with neutrophil chemotactic and activating properties, is known to be stimulated by IL-1. Fischer rats are more resistant to inflammation than Lewis rats probably due to a higher corticosteroid stress response. To determine the role of IL-8 in ocular inflammation, the effect of intravitreal injection of IL-8 was compared with that of IL-1 in both Lewis and Fischer rats. The IL-8, IL-1 alpha, or sterile balanced salt solution (control) was injected into one eye of each animal. Both IL-8 and IL-1 alpha caused inflammation in the eye of both strains, as detected by leukocyte counts of the anterior chamber and histopathologic examination. The eyes of animals injected with a cytokine had significantly higher numbers of leukocytes compared with eyes of control animals. Histopathologic examination confirmed these findings. The IL-1 alpha induced inflammation more consistently and more severely than the most effective dose of IL-8. This finding agreed with the concept of IL-1 initiating a cascade of inflammatory mediators including IL-8, which acts more specifically on a smaller population of leukocytes. A contralateral response was observed in the uninjected eye of experimental and control animals. The contralateral response in animals receiving the cytokines was significantly greater than that in controls. Lewis rats show a higher inflammatory response to the injections than do the Fischer rats. These data suggest that IL-8 may be active as one component in neutrophil-mediated ocular inflammation.
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PMID:Ocular inflammation stimulated by intravitreal interleukin-8 and interleukin-1. 201 35

Much effort has been directed toward elucidating the host response to sepsis and inflammation, resulting in the definition of a cascade of endogenous mediators that direct metabolic and immunological responses. Here we report that IL-8, a novel cytokine produced by a variety of cells in vitro in response to stimulation with bacterial LPS and the proinflammatory cytokines, appears in the circulation of primates in vivo during septic shock, sublethal endotoxemia, and after the administration of IL-1 alpha. The magnitude of the IL-8 response correlates with the severity of the insult, and levels of IL-8 peak relatively late, after those of TNF-alpha and IL-1 beta, and simultaneously with those of IL-6. IL-8 has been primarily defined as a selective activator and chemoattractant of neutrophils, and we demonstrate that after LPS or IL-1 alpha infusion, circulating neutrophil numbers rapidly recover from an initial neutropenia while IL-8 concentrations are maximal, supporting the hypothesis that IL-8 influences circulating leukocyte populations in vivo. We conclude that IL-8 is another participant in the cytokine cascade elicited by sepsis and inflammation and, as such, may play a significant role in host defense and disease.
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PMID:IL-8 in septic shock, endotoxemia, and after IL-1 administration. 202 76

Inflammatory cell activation by interleukin-1 (IL-1) has been the subject of studies in laboratory animals and man, and was the aim of the present study. At physiological concentrations of 0.01-100 units/ml, human recombinant IL-1 alpha was shown to be a chemokinetic and chemotactic agent for canine neutrophils in vitro and to cause dose-dependent and selective neutrophil infiltration following intradermal injection of 1 or 250 units. The findings support a putative role for IL-1, and IL-1-induced products such as IL-8, as mediator of immunoinflammatory reactions in which neutrophil infiltration is prominent.
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PMID:Effects of interleukin-1 alpha on migration of canine neutrophils in vitro and in vivo. 207 98

The protein-bound polysaccharide extracted from a fungus, PSK, has been used as a biological response modifier in the treatment of cancer patients in Japan for over ten years. Although the antitumor mechanism of PSK is not fully understood, host-mediated antitumor activity has been claimed to play a significant role. The administration of PSK to tumor-bearing rodents inhibited tumor growth and modulated immune responses. To clarify the potential immunomodulating activities of PSK, we examined the direct effect of PSK on cytokine gene expression and production in human peripheral blood mononuclear cells (PBMC) in vitro. As determined by Northern blotting, PSK was a potent inducer of gene expression for IL-1 alpha, IL-1 beta, IL-6, IL-8, tumor necrosis factor (TNF-alpha) and monocyte chemotactic and activating factor (MCAF), but not for IL-2 and lymphotoxin (LT). Expression of mRNA occurred at 1-3 hr in a dose dependent manner using from 5-400 micrograms/ml of PSK. Furthermore, these cytokines were also produced in response to PSK as detected by ELISA, RIA or bioassays. We speculate that these cytokines may mediate immunoenhancing actions of PSK in vivo.
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PMID:Induction of gene expression and production of immunomodulating cytokines by PSK in human peripheral blood mononuclear cells. 209 Aug 74

The liver participates in inflammation via the elaboration of acute phase proteins from hepatocytes in response to IL-1, TNF-alpha, and IL-6/INF-beta 2/hepatocyte-stimulating factor. In addition, some inflammatory states of the liver are characterized by leukocyte infiltrates. Here we demonstrate that human hepatocyte lines are capable of expressing mRNA and biologic activity for a neutrophil chemotactic factor (NCF)/IL-8 in response to the inflammatory mediators IL-1 alpha, IL-1 beta, and TNF. Two human hepatoma cell lines (SK-Hep and Hep-G2) displayed a time- and dose-dependent increase in steady state levels of NCF/IL-8 mRNA and secretion of chemotactic activity in response to TNF and IL-1. Neutralizing antibody to NCF/IL-8 inhibited hepatocyte-derived chemotactic activity by 88%. In contrast to IL-1 and TNF, hepatocytes did not respond to LPS or IL-6 within the time and dose parameters used above. Although the expression of NCF/IL-8 mRNA (1.8 kb) was first detectable between 1 and 2 h poststimulation, significant chemotactic bioactivity was not observed until about 4 h. Heat-inactivated (100 degrees C, 30 min) cytokine failed to induced NCF/IL-8 mRNA synthesis, and cotreatment of cells with cytokine and cycloheximide super-induced NCF/IL-8 mRNA while inhibiting production of bioactivity. Thus, NCF/IL-8 expression is a primary induction phenomenon. Our data demonstrate the stimulus specific induction of NCF/IL-8 in hepatocytes and suggest that cytokine cell-to-cell communication circuits may be important in neutrophil-mediated inflammatory processes in the liver.
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PMID:Cytokine-induced gene expression of a neutrophil chemotactic factor/IL-8 in human hepatocytes. 215 28


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