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)

Dendritic cells are the most potent antigen-presenting cells of the immune system. Although dendritic cells are likely to secrete selective cytokines that facilitate antigen presentation, the difficulty in isolating pure dendritic cells in sufficient numbers has made assessment of this function imprecise. In this study, pure populations of CD83+ human blood dendritic cells were isolated by previously established enrichment procedures and subsequent cell sorting. Cytokine gene expression was assessed by reverse transcription-polymerase chain reaction (RT-PCR) amplification of mRNA. Resting CD83+ dendritic cells expressed interleukin-6 (IL-6), IL-8, IL-10, tumor necrosis factor-alpha (TNF-alpha), and transforming growth factor-beta 1 (TGF-beta 1) mRNA, while activation of cells with phorbol myristate acetate induced IL-1 alpha and beta, IL-9, TNF-beta, interferon-gamma, granulocyte-macrophage colony-stimulating factor (GM-CSF), M-CSF, and G-CSF mRNA expression. Resting CD83+ cells also expressed the Rantes, MCP-1, MIP-1 alpha, and MIP-1 beta chemokines, with 1-309 expression induced upon activation. Resting and activated CD83+ dendritic cells also expressed receptors for IL-2 (CD25), TGF-beta 1 and -beta 3, and GM-CSF as determined by indirect immunofluorescence staining. These results indicate that dendritic cells have the ability to produce a variety of soluble factors which are likely to contribute substantially to the potent allostimulatory activity of these cells.
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PMID:A distinct pattern of cytokine gene expression by human CD83+ blood dendritic cells. 757 30

The Duffy antigen (DARC) is a promiscuous chemokine receptor that also binds Plasmodium vivax. DARC belongs to a family of heptahelical chemokine receptors that includes specific (IL-8RA) and shared (IL-8RB) IL-8 receptors. Ligand binding specificity of IL-8 receptors was localized to the amino-terminal extracellular (E1) domain. To determine the basis for promiscuous chemokine binding by DARC, a chimeric receptor composed of the E1 domain of DARC and hydrophobic helices and loops from IL-8RB (DARCe1/IL-8RB) was constructed. Scatchard analysis of stable transfectants demonstrated that the DARCe1/IL-8RB chimeric receptor bound IL-8 and melanoma growth stimulating activity (MGSA) with KD values almost identical to the native receptors. The hybrid receptor also bound RANTES, MCP-1, and MGSA-E6A (which binds DARC, but not IL-8RB), but not MIP-1 alpha, similarly to DARC. Ligand binding to DARC transfectants was unaltered by anti-Fy3, but inhibited by Fy6, which binds an epitope in the E1 domain. The epitope recognized by Fy3 was localized to the third extracellular loop by analysis of insect cells expressing chimeric receptors composed of complementary portions of DARC and IL-8RB. These findings implicate the E1 domain of DARC in multispecific chemokine binding.
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PMID:The promiscuous chemokine binding profile of the Duffy antigen/receptor for chemokines is primarily localized to sequences in the amino-terminal domain. 759 30

Leukocyte recruitment is a key step in the inflammatory reaction. Several changes in the cell morphology take place during lymphocyte activation and migration: spheric-shaped resting T cells become polarized during activation, developing a well defined cytoplasmic projection designated as cellular uropod. We found that the chemotactic and proinflammatory chemokines RANTES, MCP-1, and, to a lower extent, MIP-1 alpha, MIP-1 beta, and IL-8, were able to induce uropod formation and ICAM-3 redistribution in T lymphoblasts adhered to ICAM-1 or VCAM-1. A similar chemokine-mediated effect was observed during T cells binding to the fibronectin fragments of 38- and 80-kD, that contain the binding sites for the integrins VLA-4 and VLA-5, respectively. The uropod structure concentrated the ICAM-3 adhesion molecule (a ligand for LFA-1), and emerged to the outer milieu from the area of contact between lymphocyte and protein ligands. In addition, we found that other adhesion molecules such as ICAM-1, CD43, and CD44, also redistributed to the lymphocyte uropod upon RANTES stimulation, whereas a wide number of other cell surface receptors did not redistribute. Chemokines displayed a selective effect among different T cell subsets; MIP-1 beta had more potent action on CD8+ T cells and tumor infiltrating lymphocytes (TIL), whereas RANTES and MIP-1 alpha targeted selectively CD4+ T cells. We have also examined the involvement of cAMP signaling pathway in uropod formation. Interestingly, several cAMP agonists were able to induce uropod formation and ICAM-3 redistribution, whereas H-89, a specific inhibitor of the cAMP-dependent protein kinase, abrogated the chemokine-mediated uropod formation, thus pointing out a role for cAMP-dependent signaling in the development of this cytoplasmic projection. Since the lymphocyte uropod induced by chemokines was completely abrogated by Bordetella pertussis toxin, the formation of this membrane projection appears to be dependent on G proteins signaling pathways. In addition, the involvement of myosin-based cytoskeleton in uropod formation and ICAM-3 redistribution in response to chemokines was suggested by the prevention of this phenomenon with the myosin-disrupting agent butanedione monoxime. Interestingly, this agent also inhibited the ICAM-3-mediated cell aggregation, but not the cell adhesion to substrata. Altogether, these results demonstrate that uropod formation and adhesion receptor redistribution is a novel function mediated by chemokines; this phenomenon may represent a mechanism that significantly contributes to the recruitment of circulating leukocytes to inflammatory foci.
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PMID:Chemokines regulate cellular polarization and adhesion receptor redistribution during lymphocyte interaction with endothelium and extracellular matrix. Involvement of cAMP signaling pathway. 759 74

Experimental autoimmune encephalomyelitis (EAE) is a CD4+ T cell-mediated, inflammatory demyelinating disease of the central nervous system (CNS) that serves as a model for the human demyelinating disease, multiple sclerosis. A critical event in the pathogenesis of EAE is the entry of both Ag-specific T lymphocytes and Ag-nonspecific mononuclear cells into the CNS. In the present report we investigated the role of two C-C chemokines (macrophage inflammatory protein-1 alpha (MIP-1 alpha) and monocyte chemotactic protein-1) and a C-x-C chemokine (MIP-2) in the pathogenesis of EAE. Production in the CNS of MIP-1 alpha, but not that of MIP-2, a rodent homologue of IL-8, or monocyte chemotactic protein-1, correlated with development of severe clinical disease. Administration of anti-MIP-1 alpha, but not that of anti-monocyte chemotactic protein-1, prevented the development of both acute and relapsing paralytic disease as well as infiltration of mononuclear cells into the CNS initiated by the transfer of neuroantigen peptide-activated T cells. Ab therapy could also be used to ameliorate the severity of ongoing clinical disease. Anti-MIP-1 alpha did not affect the activation of encepahlitogenic T cells as measured by cytokine secretion, surface marker expression, and ability to adoptively transfer EAE. These results demonstrate that MIP-1 alpha plays an important role in directing the chemoattraction of mononuclear inflammatory cells in the T cell-mediated autoimmune disease, EAE.
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PMID:An important role for the chemokine macrophage inflammatory protein-1 alpha in the pathogenesis of the T cell-mediated autoimmune disease, experimental autoimmune encephalomyelitis. 759 7

Chemoattractants, including chemokines such as interleukin 8 (IL-8) and related proteins, activate leucocytes via seven-transmembrane-domain G-protein-coupled receptors. A cDNA for a novel receptor of this kind consisting of 327 amino acids was isolated from a human blood monocyte cDNA library. The polypeptide, termed monocyte-derived receptor 15 (MDR15), is an alternative form of the Burkitt's lymphoma receptor 1 (BLR1) encoded by a human Burkitt's lymphoma cDNA [Dobner, Wolf, Emrich and Lipp (1992) Eur. J. Immunol. 22, 2795-2799]. MDR15 and BLR1 cDNAs differ in the 5' region, where the open reading frame of MDR15 is shorter by 45 codons. Southern-blot analysis indicates that the two transcripts for MDR15 and BLR1 are encoded by the same gene. Northern-blot analysis using a probe that hybridizes with both mRNAs demonstrated high-level expression in chronic B-lymphoid leukaemia and non-Hodgkin's lymphoma cells and, to a lesser extent, peripheral blood monocytes and lymphocytes. Reverse transcription-PCR studies with MDR15- and BLR1-specific primers showed similar levels of transcripts for both receptors in RNA that was positive in Northern-blot analysis. MDR15 and BLR1 have high structural similarity to receptors for human IL-8 (about 40% amino acid identity) and other chemokines. However, none of a series of radiolabelled chemokines (IL-8, NAP-2, GRO alpha, PF4, IP10, MCP-1, MCP-2, MCP-3, I-309, RANTES and MIP-1 alpha) and other ligands (C3a and leukotriene B4) bound to Jurkat transfectants that stably expressed either MDR15 or BLR1 mRNA. The fact that MDR15 and BLR1 are expressed on leucocytes and show marked sequence similarity to chemokine receptors suggests the existence of as yet unidentified chemokines. Alternative transcript formation affecting the 5'-terminal part of the coding region may be a way to modify ligand-binding selectivity.
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PMID:Sequence variation of a novel heptahelical leucocyte receptor through alternative transcript formation. 763 92

Fibrosis of the pulmonary parenchyma is a frequent and serious complication of scleroderma (systemic sclerosis, SSc), resulting in significant morbidity and mortality. During the past decade data have accumulated in support of an inflammatory process affecting the alveoli and distal airways that culminates in irreversible fibrosis in many SSc patients. Recent findings indicate the presence of lung fibroblasts with altered phenotype and biologic activity (myofibroblasts), perhaps arising from the influence of cytokines on resident lung fibroblasts. Acute-phase inflammatory cytokines such as IL-1 alpha, TNF-alpha, MIP-1 alpha, IL-8 and RANTES are increased in SSc bronchoalveolar lavage (BAL) fluid, as is thrombin, a potent mitogen for lung fibroblasts. Chronic-phase inflammatory and fibrogenic cytokines such as PDGF and TGF-beta are also present in increased amounts in SSc BAL fluid. The inciting event(s) and the process(es) leading to the perpetuation of fibrosis in SSc are unknown. Treatment of SSc lung disease has been empiric and generally disappointing, and it is likely that effective treatment awaits a better understanding of the biological events that regulate collagen and other extracellular matrix synthesis.
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PMID:Interstitial lung disease of systemic sclerosis. 765 Apr 24

Two subfamilies of chemokines are distinguished depending on the arrangement of the first two of four conserved cysteines, which are either separated by one amino acid (CXC chemokines) or adjacent (CC chemokines). IL-8 and the other CXC chemokines act preferentially on neutrophils, while the CC chemokines (MCP-1, MCP-2, MCP-3, RANTES, MIP-1 alpha and MIP-1 beta) act on monocytes, but not neutrophils, and have additional activities toward basophil and eosinophil granulocytes, and T-lymphocytes. Several chemokine receptors have been identified, all of which belong to the seven-transmembrane-domain type and are coupled to G-proteins. The discovery of chemokines has provided the basis for the understanding of leukocyte recruitment and activation in inflammation and other disturbances of tissue homeostasis.
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PMID:Interleukin-8 and the chemokine family. 765 3

To study the effect of localised secretion of chemokines on tumour growth, the genes for human (hu) interleukin 8 (IL-8), hu-MCP-1 (MCAF), hu-MIP-1 alpha (LD78), murine (mu)-MCP-1 (JE), mu-MIP-1 alpha or mu-MIP-2 were introduced, via mammalian expression vectors, into Chinese hamster ovary (CHO) cells, and the ability of transfected cells to form tumours in vivo was evaluated. The production of hu-IL-8, hu-MIP-1 alpha or mu-MIP-1 alpha by transfected clones did not influence the growth rate in vitro, but drastically suppressed tumour growth when injected subcutaneously (s.c.) into nude mice. However, clones transfected with hu-MCP-1, mu-MCP-1 or mu-MIP-2 did not show any significant difference in growth rate in vivo compared with clones transfected with vector alone. Histological examination of the site of injection of CHO clones transfected with hu-IL-8, hu-MIP-1 alpha or mu-MIP-1 alpha showed predominantly neutrophilic infiltration. These results indicate that chemokines have potent anti-tumour activity when released, even at low doses, at the tumour site, which may be mediated by recruitment and targeting of neutrophilic granulocytes to chemokine-releasing cells. Our studies highlight the potential usefulness of localised chemokine secretion in inducing potent host anti-tumour defensive responses.
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PMID:Chemokine gene transfection into tumour cells reduced tumorigenicity in nude mice in association with neutrophilic infiltration. 766 85

We have previously shown that platelet factor 4 (PF4), a platelet-specific CXC chemokine, can directly and specifically inhibit human megakaryocyte colony formation. We therefore hypothesized that PF4 might function as a negative autocrine regulator of megakaryocytopoiesis. Herein we present additional studies characterizing the inhibitory effect of CXC chemokines on human megakaryocyte development. We first corroborated our initial studies by showing that recombinant human (rH) PF4, like the native protein, inhibited megakaryocytopoiesis. We then examined the inhibitory properties of other CXC family members. Neutrophil activating peptide-2 (NAP-2), a naturally occurring N-terminally cleaved beta TG peptide, was found to inhibit megakaryocytopoiesis with two to three orders of magnitude greater potency than PF4. Structure function studies showed that an N-terminal mutation, which eliminated NAP-2's neutrophil activating properties (NAP-2E2-->A), also abrogated its ability to inhibit megakaryocyte development. Further investigations of this type demonstrated that a chimeric PF4 protein (AELR/PF4) in which PF4's N-terminus was replaced with the first four amino acids of NAP-2 was also a potent inhibitor of megakaryocytopoiesis. Interleukin (IL)-8, another CXC chemokine, and three CC chemokines (macrophage inhibitory protein-1 alpha [MIP-1 alpha], MIP-1 beta, and C10) also specifically inhibited megakaryocyte colony formation at NAP-2 equivalent doses. CXC and CC chemokine inhibition was additive suggesting that the effects might be mediated through a common pathway. The inhibitory effects of NAP-2 and MIP-1 alpha could not be overcome by adding physiologically relevant amounts of recombinant human megakaryocyte growth and development factor (MGDR) (50 ng/mL) to the cultures. Using Northern blot and reverse transcriptase-polymerase chain reaction (RT-PCR) based analyses, we documented mRNA expression of IL-8 receptor isoforms alpha and beta in total platelet RNA and in normal human megakaryocytes, respectively. Based on these results, we hypothesize that chemokines play a physiologic role in regulating megakaryocytopoiesis. Because chemokines are elaborated by ancillary marrow cells, both autocrine and paracrine growth control is suggested, the effects of which might be exerted, in part, through alpha and beta IL-8 receptors.
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PMID:Chemokine regulation of human megakaryocytopoiesis. 767 Jan 1

Chemotactic cytokines related to interleukin-8 (IL-8; CXC-chemokines) or monocyte chemotactic protein-1 (MCP-1; CC-chemokines) have been shown to stimulate human basophils, and are considered important tissue-derived mediators of inflammation. We have studied the effects of four CC-chemokines and show that MCP-1, RANTES (regulated on activation, normal T expressed and secreted) and macrophage inflammatory protein-1 alpha (MIP-1 alpha) are potent basophil agonists inducing a rapid change of cytosolic free calcium ([Ca2+]i), the release of histamine and sulfido-leukotrienes, and chemotaxis. MCP-1 was the most potent stimulus of release, and the only chemokine that induced marked exocytosis in basophils without pretreatment with interleukin-3. RANTES was the strongest stimulus of chemotaxis, but only a moderate stimulus of release. MIP-1 alpha elicited relatively weak chemotaxis and release responses, but was effective at considerably lower concentrations than MCP-1 and RANTES. MIP-1 beta, by contrast, despite its high homology to MIP-1 alpha, was totally inactive. Normodense human eosinophils, tested for comparison, responded in a similar fashion to RANTES and MIP-1 alpha, but were unresponsive to MCP-1 and MIP-1 beta. All CC-chemokines except MIP-1 beta induced a similar rapid and transient rise of [Ca2+]i that was sensitive to pertussis toxin, indicating that they activate basophils via G-protein-coupled receptors. Cross-desensensitization experiments indicate that basophils bear different CC-chemokine receptors. Some interact selectively with MCP-1 or RANTES, while others are shared by RANTES and MIP-1 alpha.
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PMID:RANTES and related chemokines activate human basophil granulocytes through different G protein-coupled receptors. 768 Jun 15


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