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

GRO alpha and neutrophil-activating peptide 2 (NAP-2), like their analog interleukin 8 (IL-8), are considered to be inflammatory mediators since they recruit and activate neutrophil leukocytes. After introduction of tyrosines by substitution for other residues at the C terminus, GRO alpha and NAP-2 were labeled with 125I and used for binding studies. A total of 60,000-90,000 receptors per neutrophil were found for either ligand. Of these 30-45% were of high affinity with a mean Kd value of 0.3 and 0.7 nM for GRO alpha and NAP-2, respectively, and 55-70% of low affinity (Kd = 30 nM). Two proteins of approximately 70 kDa and 44 kDa (p70 and p44) were specifically cross-linked with labeled GRO alpha, NAP-2, and IL-8. Unlabeled IL-8 fully inhibited this cross-linking and the binding of labeled GRO alpha or NAP-2 to the high-affinity sites on neutrophils or neutrophil membranes. Treatment of membranes with digitonin resulted in the preferential solubilization of a single receptor species, corresponding to p44, that bound GRO alpha and NAP-2 with low affinity (Kd = 30 nM) and IL-8 with high affinity (Kd = 0.4 nM). Exposure of neutrophil membranes to 100 microM guanosine 5'-[gamma-thio]triphosphate led to a 75-fold increase of the Kd in approximately 60% of the IL-8 receptors. High-affinity receptors for GRO alpha and NAP-2 were similarly affected. In contrast, guanosine 5'-[gamma-thio]triphosphate had no effect on the binding of IL-8 to p44 solubilized by digitonin. These results demonstrate that human neutrophils bear two classes of receptors for GRO alpha, NAP-2, and IL-8 (p70 and p44) that may differ in their mode of interaction with GTP regulatory proteins.
 ...
PMID:High- and low-affinity binding of GRO alpha and neutrophil-activating peptide 2 to interleukin 8 receptors on human neutrophils. 143 44

Interleukin-2 (IL-2)-dependent large granular lymphocytes (LGL) with a distinctive surface phenotype were generated from histologically normal duodenal biopsy tissues. Immunoperoxidase staining of the mucosa with an anti-CD56 monoclonal antibody revealed LGL localized in the lamina propria rather than in the epithelium. Light and electron microscopy demonstrated azurophilic and electron-dense cytoplasmic granules. Flow cytometry analysis revealed that these cells express CD45, CD56, CD2, CD7, CD11a, CD18, CD69 and the intermediate affinity (p70) IL-2 receptor (IL-2R) but not CD57, CD16, CD3, CD4, CD5, CD8, CD45RA, CD25, or the high affinity p55 IL-2R. The LGL proliferated when cultured in the presence of human rIL-2 but not in the presence of human rIL-4. Functional studies demonstrated that the LGL had strong cytotoxicity against natural killer (NK) target cells, K562, but not NK-resistant targets such as Colo 205, Melanoma and Epstein-Barr virus (EBV)-transformed B-cell lines. The LGL expressed genes for IL-5, IL-8, granulocyte-macrophage colony-stimulating factor (GM-CSF) and tumour necrosis factor-alpha (TNF-alpha) and the corresponding cytokines were detected in culture supernatant. These results provide evidence for an important role of gut mucosal LGL in the induction and regulation of inflammation and immunity in the gut.
 ...
PMID:Morphological, phenotypic and functional characteristics of a pure population of CD56+ CD16- CD3- large granular lymphocytes generated from human duodenal mucosa. 769 28

Two cDNAs coding for distinct interleukin 8 (IL-8) receptors, IL-8R1 [Murphy and Tiffany (1991) Science 253, 1280-1283] and IL-8R2 [Holmes, Lee, Kuang, Rice and Wood (1991) Science 253, 1278-1280] have been reported, and biochemical studies on human neutrophils have revealed two proteins (p70 and p44) that bind IL-8 with high affinity [Moser, Schumacher, von Tscharner, Clark-Lewis and Baggiolini (1991), J. Biol. Chem. 266, 10666-10671]. We have cloned the cDNA coding for IL-8R1 from a library of differentiated HL-60 cells. Transfection of this cDNA into Jurkat cells resulted in the expression of high-affinity binding for IL-8 and two related cytokines, GRO alpha and neutrophil-activating peptide 2 (Kd 0.5-1.0 nM). Northern-blot analysis with the IL-8R1 cDNA as probe revealed abundant expression of transcripts of different size in human neutrophils and low-level expression of a single RNA species in HL-60 cells differentiated with dimethyl sulphoxide and retinoic acid. Because of the extensive nucleotide sequence similarity of the cDNAs for IL-8R1 and IL-8R2, the reverse-transcription PCR method was used for analysis of RNA expression in myeloid and lymphoid cells, 19 cell lines established from human primary melanomas or metastases, two melanocyte and one fibroblast cell lines. IL-8R1 mRNA transcripts were expressed at high levels in neutrophils, and to a lesser extent in blood monocytes and the myeloid cell lines, HL-60 and AML 193, but were not found in THP-1 cells, lymphocytes and Jurkat cells. IL-8R2 mRNA transcripts, by contrast, were found in all blood cells and related cell lines, as well as in all melanoma, melanocyte and fibroblast cell lines tested. As for IL-8R1, IL-8R2 mRNA expression was highest in neutrophils. These results suggest that IL-8R1 and IL-8R2 may both be involved in neutrophil activation by IL-8 and related cytokines, and presumably correspond to p70 and p44, the receptors that were identified biochemically. Possible IL-8 functions on lymphocytes and melanoma cells, e.g. chemotaxis and proliferation, must be independent of IL-8R1 and may be mediated by IL-8R2.
 ...
PMID:Expression of transcripts for two interleukin 8 receptors in human phagocytes, lymphocytes and melanoma cells. 836 81

Interleukin (IL)-12 is thought to be a key factor for the induction of interferon gamma (IFN-gamma), a cytokine essential for the lethal effects of endotoxin. We report here on the release of the nonfunctional subunit of IL-12, p40, as well as biologically active heterodimeric IL-12, p70, after administration of a lethal (n = 5) or sublethal (n = 8) dose of live Escherichia coli to baboons. Remarkably, on lethal challenge, peak levels of p40 were observed at 3 hours that were about twofold lower than those elicited after sublethal challenge (2,813 +/- 515 pg/mL v 4,972 +/- 732 pg/mL, P < .05). This disparity was also observed, although to a lesser extent, for IL-12 p70 antigen, of which maximum levels of 91 +/- 47 pg/mL and 151 +/- 41 pg/mL were measured 6 hours after a lethal or sublethal dose of E coli, respectively. Circulating p70 antigen correlated with IL-12 biologic activity (r = 0.869; P < .001). When comparing lethal to sublethal conditions, lower peak levels of IL-12 on lethal E coli sharply contrasted with higher levels of other proinflammatory cytokines, such as tumor necrosis factor (TNF)-alpha, IL-1beta, IL-6, and IL-8 observed in these animals. Lower IL-12 concentrations in the lethal group may have resulted in part from the enhanced production of IL-10, a known inhibitor of IL-12 synthesis in vitro, as peak levels of this cytokine 3 hours postchallenge inversely correlated with peak levels of IL-12, in particular p40 (r = -0.802; P < .01). Contrary to what might be expected if IFN-gamma were solely induced by IL-12, lethally challenged baboons generated threefold more IFN-gamma at 6 hours than those receiving a sublethal dose (P < .05). Moreover, higher levels of IFN-gamma were associated with lower p40/p70 ratios, suggesting that, in agreement with observations in vitro, IFN-gamma may have preferentially upregulated the release of p70 over p40. These data show that IL-12 is released in experimental septic shock in nonhuman primates and suggest that IL-10 and IFN-gamma are involved in the regulation of this release. Furthermore, this study indicates that the systemic release of IL-12 might be essential, but is not likely sufficient, to promote lethal production of IFN-gamma in sepsis.
 ...
PMID:Release of interleukin-12 in experimental Escherichia coli septic shock in baboons: relation to plasma levels of interleukin-10 and interferon-gamma. 865 27

To assess the role of interleukin-12 (IL-12) and gamma interferon (IFN-gamma) in children with bacterial meningitis, bioactive IL-12 (p70) and the inactive subunit p40 and IFN-gamma were measured in serum and cerebrospinal fluid (CSF) from 35 children with bacterial meningitis and 10 control subjects. The production of IFN-gamma is induced by IL-12 with tumor necrosis factor alpha (TNF-alpha) as a costimulator and inhibited by IL-10. CSF concentrations of IL-12 p40 as well as those of IFN-gamma were markedly elevated, whereas IL-12 p70 was hardly detectable. Detectable CSF levels of IFN-gamma correlated positively with IL-12 p40 (r = 0.40, P = 0.02) and TNF-alpha (r = 0.46, P = 0.04) but not with IL-6, IL-8, or IL-10. In contrast to CSF levels of TNF-alpha, IL-12, and IL-10, those of IFN-gamma were significantly higher in patients with pneumococcal meningitis than in children with meningitis caused by Haemophilus influenzae and Neisseria meningitidis, presumably because of a high CSF TNF-alpha/IL-10 ratio in the former. We suggest that IL-12- and TNF-alpha-induced IFN-gamma production may contribute to the natural immunity against microorganisms in the CSF compartment during the acute phase of bacterial meningitis.
 ...
PMID:Intrathecal production of interleukin-12 and gamma interferon in patients with bacterial meningitis. 903 91

We have examined in detail the activities of IL-13 on monokine production in vitro and compared its effects with those of IL-10 and IFN-gamma. IL-13 and IL-10 show qualitatively and quantitatively similar activities on cytokine production by monocytes when administered simultaneously with LPS i.e. inhibition of IL-1, IL-6 and TNF-alpha, up-regulation of IL1-ra. However when either LPS and IFN-gamma or fixed S. aureus Cowan (SAC) are used to activate monocytes, IL-10 is a much more potent inhibitor of TNF-alpha production than is IL-13. IL-10 is also an extremely potent inhibitor of IL-12 (p70) production when given with either SAC or LPS, while IL-13 has little effect. Indeed, IL-13 actually increases SAC-induced IL-12 production. When IL-13 is administered prior to the LPS stimulation, its modulation of cytokine production is drastically different. Production of IL-12, MCP-1, TNF-alpha and to a lesser extent IL-6 induced by LPS is now "primed", whereas that of IL-1, IL-8, and IL-10 is still inhibited. IL-10 does not show this "priming" effect, and is a dominant inhibitor of IL-13. The initial IL-13 priming effect is not however due to an inhibition of endogenous IL-10 production; nor is it due to inhibition of PGE2 production. The priming effect of IL-13 on IL-12 production is additive with that of IFN-gamma, and is partly independent of IFN-gamma. The earliest event in IL-13 priming so far noted is an increase in TNF-alpha mRNA production at 1-2 hours. IL-13 priming of IL-12 production can be completely abolished by anti-TNF-alpha antibodies suggesting that IL-13 may be priming via increased TNF-alpha expression, although merely substituting TNF-alpha for IL-13 does not reproduce the priming effect. IL-13 is a thus a more subtle immune regulator than IL-10 or IFN-gamma. When administered with LPS or SAC, it dampens the resulting inflammatory response, though in a more selective way than IL-10. In contrast, when it is added before an inflammatory signal, it primes an immunostimulatory monokine secretion profile resembling that of IFN-gamma, but without the proinflammatory IL-1 component. Early in response to an inflammatory stimulus, IL-13 may thus play an essentially anti-inflammatory role, switching to a primarily immunostimulatory role in the case of an ongoing infection.
 ...
PMID:Interleukin-13 effects on activated monocytes lead to novel cytokine secretion profiles intermediate between those induced by interleukin-10 and by interferon-gamma. 926 68

IL-12 is a heterodimeric cytokine produced by phagocytic and other cells with important physiologic and pathologic properties. Regulated IL-12 production is crucial for the generation of protective Th1 responses to infectious agents. In contrast, IL-12 excess contributes to the pathogenesis of a variety of autoimmune and inflammatory disorders. To further understand the processes regulating IL-12 production, we determined whether IL-11 regulated monocyte/macrophage production of this cytokine moiety. IL-11 did not alter the IL-12 (p70) production of unstimulated THP-1 monocytic cells or human blood monocytes. It did, however, inhibit, in a dose-dependent fashion, the IL-12 production of IFN-gamma plus Staphylococcus aureus Cowan strain 1-stimulated THP-1 cells and stimulated blood monocytes. This inhibition of IL-12 protein production was associated with a proportionate decrease in IL-12 p35 and p40 mRNA accumulation. Nuclear run-on assays revealed comparable decreases in IL-12 p35 and p40 gene transcription. IL-11 did not similarly regulate monocyte/macrophage production of IL-8 or macrophage inflammatory protein-1alpha (MIP-1alpha) and IL-6 did not similarly inhibit IL-12 elaboration. These studies demonstrate that IL-11 is a potent inhibitor of monocyte/macrophage IL-12 production and that this inhibitory effect is, at least in part, transcriptionally mediated. They also demonstrate that this inhibition is not the result of a generalized suppression of macrophage effector function and that the ability to inhibit monocyte/macrophage IL-12 production is not a generalized property of all IL-6-type cytokines.
 ...
PMID:Interleukin-11 inhibits macrophage interleukin-12 production. 927 3

Plasma levels of interleukin 12 (IL-12), a cytokine consisting of two different polypeptide subunits (p40 and p35), were measured together with interferon gamma (IFN-gamma) and other cytokines in 46 children with septic shock and purpura. The median (range) plasma IL-12 p40 level on admission was 457 (244-2677) pg/ml in non-survivors vs 189 (< 40-521) pg/ml in survivors (P = < 0.001). IL-12 p70 levels were elevated in only nine patients. IL-12 p40 plasma levels were positively correlated with tumour necrosis factor alpha (TNF-alpha), IL-6, IL-8, IL-10 and PRISM-score, whereas they were negatively correlated with C-reactive protein (CRP), whole blood cell (WBC) and serum glucose levels. Twelve (29%) of the patients had detectable levels of IFN-gamma. Thus, circulating levels of IL-12 p40 and to a lesser extent those of IL-12 p70, are elevated in children with septic shock and purpura, and correlate with severity of disease and outcome.
 ...
PMID:Interleukin 12 levels during the initial phase of septic shock with purpura in children: relation to severity of disease. 932 21

It has been suggested that the immunopharmacological activity of soluble (1-->3)-beta-D-glucan depends on it's conformation in mice. In this study, we examined the relationship between the conformation of Schizophyllan (SPG), a high molecular weight (1-->3)-beta-D-glucan, and cytokine productivity in an in vitro human system. Monocyte-like human cell lines, THP-1 and U-937, and peripheral blood mononuclear cells (PBMC) were used. THP-1 and U-937 cells were differentiated by phorbol myristate acetate (PMA) before use. SPG usually has a triple helical conformation in water, but it was modified by treatment with aqueous sodium hydroxide to become a single helical conformer (SPG-OH). SPG or SPG-OH was added to the macrophage cell culture and gene expression and translation of several cytokines was analyzed by RT-PCR, ELISA, or bioassays. Differentiated THP-1 expressed high levels of cytokine genes, such as IL-8, in response to SPG-OH. High levels of IL-12 p70 were detected from THP-1 cells stimulated with SPG-OH. U-937 cells expressed high levels of IL-8 and TNF-alpha after SPG-OH treatment. Furthermore, PBMC isolated from healthy donors also strongly reacted with SPG-OH but not with SPG. High concentrations of TNF-alpha were detected in SPG-OH-stimulated PBMC cultures. These data suggest that the biological activities of SPG are strongly associated with its conformation in humans.
 ...
PMID:Cytokine synthesis of human monocytes stimulated by triple or single helical conformer of an antitumour (1-->3)-beta-D-glucan preparation, sonifilan. 986 84

We studied the effects of interferon-beta (IFN-beta) on the differentiation of dendritic cells (DC) obtained by culturing plastic-adherent peripheral blood mononuclear cells (PBMC) from a total of 30 healthy volunteers in the presence of granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-4 (IL-4). First, we found that the addition of IFN-beta at the initiation of the culture did not modify DC morphology but caused a reproducible and statistically significant upregulation of HLA-DR, CD86, and CD80 surface expression. CD1a expression was significantly reduced, and CD40 expression was unchanged. We then determined the influence of IFN-beta on the production of cytokines by DC. DC differentiated in the presence of IFN-beta secreted significantly less IL-12 (p40 and p70) both spontaneously and on activation by fibroblasts transfected with the CD40L gene. This effect of IFN-beta was dose dependent and selective, as it was not observed for IL-6, IL-8, and tumor necrosis factor-alpha (TNF-alpha). As a consequence, DC differentiated in the presence of IFN-beta induced significantly less IFN-gamma secretion by alloreactive T cells, whereas they were more efficient than control DC in eliciting IL-5 secretion. We conclude that the direct action of IFN-beta on DC causes inhibition of their ability to secrete IL-12 in response to CD40 ligation and to elicit Th1 type responses.
 ...
PMID:IFN-beta interferes with the differentiation of dendritic cells from peripheral blood mononuclear cells: selective inhibition of CD40-dependent interleukin-12 secretion. 1038 59


1 2 3 4 5 6 7 8 Next >>