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)

Chemokines are a family of small proteins that are present in a variety of inflammatory conditions and have been shown to activate and recruit a wide variety of cell types. They bind to a family of seven transmembrane G-protein-coupled receptors. Models for the interaction of the chemokines with their receptors suggest a two-step mechanism. Initially, the main body of the chemokine interacts with the outside of the receptor (Site 1), and this interaction directs receptor selectivity. Subsequently, the flexible amino-terminus of the chemokine interacts with the receptor core (Site 2) to initiate the signaling response. Mutagenesis studies of IL-8, the archetypal CXC chemokine, show that altering the protein on the third beta-sheet can change the receptor selectivity from that of a CXC chemokine and introduce CC chemokine activity-confirming the role of this region in Site 1. Mutagenesis studies of the amino-terminal region of IL-8 showed that a tripeptide, ELR, was essential for the interaction with Site 2. We have shown, using synthetic peptides and site-directed mutagenesis, that the amino-terminus of RANTES is important in the signaling response (Site 2). Mutations that alter only the interaction with Site 2 are capable of binding the receptor and not signaling and are therefore potential antagonists. Such antagonists have now been made by several groups, for a number of the chemokine receptors, and are active at nanomolar concentrations. These can now be used to test the hypothesis that antagonism of chemokine receptors will lead to a reduction in inflammation in vivo.
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PMID:The Molecular Basis of the Chemokine/Chemokine Receptor Interaction-Scope for Design of Chemokine Antagonists 881 52

Leukocyte infiltration into an inflammatory site is one of the pathological hallmarks of inflammatory reaction. Locally produced chemotactic factors are presumed to mediate the sequence of events leading to tissue injury associated with the infiltration of leukocytes. Chemotactic cytokines (chemokines) have been identified as being produced by various types of cells upon stimulation with inflammatory stimuli and exhibit a variety of effects on leukocytes in vitro and in vivo. Administration of highly specific neutralizing antibodies against these chemokines in several types of animal inflammation models clearly suggests important roles of these chemokines in recruiting and activating specific types of leukocytes at the inflammatory sites. Anti-IL-8 Ab treatment prevented neutrophil-dependent tissue damage as well as neutrophil infiltration in lipopolysaccharide (LPS)-induced dermatitis, LPS/IL-1-induced arthritis, lung reperfusion injury, and acute immune complex type glomerulonephritis in rabbits. Moreover, anti-MCP-1 Ab and anti-RANTES Ab inhibited macrophage infiltration in IgA immune complex alveolitis in rats and influx of lung macrophages in a murine model of endotoxemia, respectively. The use of anti-MIP-1alpha Ab also revealed that MIP-1alpha mediates eosinophil infiltration in allergic, granulomatous reactions in vivo.
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PMID:Use of Blocking Antibodies as Probes for in Vivo Functions of Chemokines 881 62

We studied the involvement of chemokines that bind to G protein-coupled receptors in the migration of skin homing T cells across a bilayer vascular construct (BVC) consisting of a fibroblast matrix underneath an activated endothelial (EC) monolayer. Based on the expression of the cutaneous lymphocyte-associated antigen (CLA), a skin homing receptor, CD45R0+ T cells freshly isolated from blood or HUT-78 cutaneous T lymphoma cells were separated into CLA+ and CLA- subpopulations. These T cells were incubated on interleukin (IL)-1 beta and tumor necrosis factor-alpha-activated EC, and the number of transmigrated cells was determined. The chemokine IL-8 was selectively involved in the enhanced migration of CLA+ T cells across activated EC as demonstrated by blocking antibody to IL-8 but not to GRO-alpha, MCP-1 and RANTES. Identical results were obtained with both human umbilical vein EC (HUVEC) and microvascular skin EC (HDMEC). Pertussis toxin selectively inhibited the enhanced transendothelial migration (TEM) of CLA+ T cells, suggesting that CLA-dependent TEM depends on Gi protein-transmitted signals. Moreover, the IL-8 receptor B (IL-8RB) appeared to be functionally involved in TEM, as demonstrated by receptor desensitization with the CXC chemokines IL-8 and GRO-alpha and by blocking the IL-8RB with specific monoclonal antibodies. Although only the IL-8RB was involved in CLA-dependent TEM, mRNA encoding IL-8RA and IL-8RB was expressed by both CLA+ and CLA- T cells. This correlated with IL-8RA and IL-8RB surface expression on these cells. Thus, the IL-8RB is selectively functional in TEM of T cells expressing the skin homing receptor CLA. Our results demonstrate a critical role for IL-8 and possibly other IL-8RB ligands in addition to the IL-8RB in TEM and suggest the involvement of these molecules in the homing of specific T cells to inflamed skin.
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PMID:The interleukin-8 receptor B and CXC chemokines can mediate transendothelial migration of human skin homing T cells. 881 46

Because dendritic cells (DC) are the most potent antigen-presenting cells involved in many pathophysiological responses, we investigated the effect of chemokines on the migration of these cells in an effort to determine whether chemokines may contribute to the initiation of immune responses. CD34+ progenitor cells isolated from umbilical cord blood were grown in suspension cultures with cytokines and expanded 50- to 100-fold. A variable proportion of the cells expressed markers consistent with DC. The proportion of CD1a+ DC was increased when the cells were cultured with interleukin-4 (IL-4). These cells expressed specific binding sites for C-C and C-X-C chemokines. Cells cultured with or without IL-4 had similar binding profiles. All C-C chemokines tested, including monocyte chemotactic protein (MCP)-1, MCP-2, MCP-3, macrophage inflammatory protein-1 alpha (MIP1 alpha), MIP-1 beta, and RANTES, induced migration of DC-enriched cells cultured with or without IL-4 with MCP-3 being the most potent chemoattractant. Phenotypic analysis of cell migrating in response to C-C chemokines showed that CD1a+ cells were indeed attracted across the polycarbonate filters, and there was no preferential attraction of contaminating CD14+ monocytes by C-C chemokines. DC-enriched cells also expressed specific binding sites for IL-8 and NAP2, which failed to induce cell migration. Our results suggest that C-C chemokines may participate in the recruitment of DC to amplify host defense.
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PMID:Human recombinant monocyte chemotactic protein and other C-C chemokines bind and induce directional migration of dendritic cells in vitro. 883 Jul 93

Chronic hyperglycemia is thought to be important in the development of diabetic neovascularization but the mechanisms involved remain poorly understood. Interleukin-8 (IL-8) is a leukocyte chemokine and activating agent with angiogenic properties that is present in diabetic vitreous and may play a role in diabetic vasculopathy. We studied IL-8 and monocyte chemotactic protein-1 (MCP-1) production by human retinal pigment epithelial (hRPE) cells exposed to glycated human serum albumin (GHSA). Enzyme-linked immunoassay GHSA (500 micrograms/mL)-treated hRPE cells secreted levels of IL-8 and MCP-1 detectable within 4 h and reached 26.0 +/- 1.3 and 42.2 0.4 ng/10(6) cells/mL after 24 h, respectively. Induction of IL-8 and MCP-1 by GHSA at concentrations ranging from 62.5 to 3,000 micrograms/mL exhibited dose-dependent kinetics. The GHSA-induced chemokine secretion by hRPE was almost completely inhibited by actinomycin D and cycloheximide, suggesting that de novo mRNA and protein synthesis are necessary for the GHSA-induced IL-8 and MCP-1 production. Northern blot analysis of GHSA-induced hRPE IL-8 and MCP-1 mRNA expression corresponded to the time- and dose-dependent increases measured by enzyme-linked immunosorbent assay. High concentrations of glucose (20 mM; 360 mg/dl) increased GHSA-induced hRPE IL-8 and MCP-1 secretion, whereas added insulin (0.5 ng/mL) inhibited IL-8 but not MCP-1 protein secretion and mRNA expression. GHSA also induced hRPE to secrete GRO-alpha, RANTES, and NAP-2 chemokines. GHSA induction of hRPE chemokines further suggests a role for the hRPE in leukocyte infiltration, vascular injury, and neovascularization.
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PMID:Glycated serum albumin induces chemokine gene expression in human retinal pigment epithelial cells. 883 Jul 98

Following the intracranial injection of lipopolysaccharide or during acute neuronal degeneration, there is a paucity of polymorphonuclear leukocyte recruitment to the brain parenchyma and a delay in monocyte recruitment. The present study investigates whether the injection of specific leukocyte chemoattractants into the murine central nervous system can override this intrinsic resistance. Recombinant alpha-(IL-8/NAP-1 MIP-2, IP-10) and beta-chemokines (MCP-1, RANTES) were injected into the murine hippocampus and leukocyte recruitment was assessed histologically. Injections were also made into the dermis of the hind flank for comparison. At doses of 1 microgram, MCP-1 was found to be the most potent monocyte chemoattractant in the brain parenchyma and skin with IP-10 and RANTES producing minimal monocyte recruitment to both sites. In contrast IL-8, and MIP-2 provoked dramatic polymorphonuclear leukocyte recruitment in both the central nervous system and skin. The polymorphonuclear leukocyte recruitment was associated with a breaching of the blood brain barrier that was particularly severe after MIP-2. Both L-8 and MIP-2 induced blood brain barrier breakdown could be attenuated by prior depletion of the circulating leukocytes. The regulation of polymorphonuclear leukocyte chemoattractants in the brain parenchyma during injury and infection is an important area for future studies.
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PMID:Overriding the brain's intrinsic resistance to leukocyte recruitment with intraparenchymal injections of recombinant chemokines. 884 93

Cell priming and stimulation of different cytokines (which include chemokines and growth factors) are typical features of human basophils. Recently, it has been shown that the macrophage chemotactic protein-1 (MCP-1), RANTES and macrophage inflammatory protein-1 alpha (MIP-1 alpha) are potent direct secretagogues for human basophils and that interleukin-3 (IL-3), IL-5 and granulocyte/macrophage colony-stimulating factor (GM-CSF) are priming factors for subsequent potentiation of mediator release from basophils induced by different stimuli. This observation may be clinically important for the activation and recruitment of inflammatory cells in different immune responses of the skin (e.g. late-phase reactions). The aim of the present study was to investigate whether cytokines and chemokines are also capable of priming or stimulating isolated human skin mast cells (SMC). SMC were either stimulated directly with the cytokines alone or preincubated with these factors for 10 min before being activated with suboptimal concentrations of anti-IgE, A23187 or substance P. IL-3, IL-5, GM-CSF, platelet factor-4 (PF-4), IL-8, MCP-1 and MIP-1 alpha (each at concentrations of 1 ng/ml to 1 microgram/ml, log steps) did not significantly modulate histamine release from SMC induced by the three different secretagogues. RANTES exhibited a weak but significant potentiating effect on IgE-mediated activation. Stem cell factor (SCF) as a positive control was able to prime mast cell histamine release strongly. In addition, PF-4, MCP-1, RANTES and MIP-1 alpha were incapable of inducing direct histamine release from SMC. In experiments with isolated human peripheral basophils, however, we observed potent Fc epsilon RI-mediated priming effects evoked through IL-3, IL-5 and GM-CSF. We conclude that SMC derived from healthy donors are not targets of (immuno)modulatory factors that prime or stimulate basophils.
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PMID:Effects of basophil-priming and stimulating cytokines on histamine release from isolated human skin mast cells. 884 26

Breast feeding improves the health of children. The greatest significance is to host defense, prevention of autoimmunity, and development of the digestive system; however, the underlying mechanisms for these effects are not well understood. Based on recent evidence that cytokines might be important in these processes, we have used ELISA to quantitate the cytokines in human colostrum, transitional, and mature milk from mothers delivering preterm or at term. We also used reverse transcription PCR to test breast milk cells for the production of cytokine mRNA. No significant (< 10 pg/ml) GM-CSF, SCF, LIF, MIP-1 alpha, IL-2, IL-4, IL-11, IL-12, IL-13, IL-15, sIL-2R, or IFN-gamma was detected. And, in contrast to earlier studies using bioassays or RIA, no significant IL-1 beta, TNF-alpha, or IL-6 was present; nor was IL-10, which had been tested using less specific antibodies. We did confirm the presence of high levels of M-CSF, which remained high throughout lactation. Human milk contained latent, but not free, TGF-beta 1, and especially TGF-beta 2, both of which may be activated by gastric acid pH. High levels of IL-1RA were detected, and like activated TGF-beta, may protect against autoimmunity. Chemokines, particularly GRO-alpha and MCP-1, but also RANTES and IL-8, were present and could protect against infection. Maternal cells in breast milk expressed mRNA for MCP-1 (20/20), IL-8 (14/20), TGF-beta 1 (14/16), TGF-beta 2 (4/6), M-CSF (9/12), IL-6 (6/12) and IL-1 beta (7/12), and may be a source of these cytokines. mRNA for IL-2, IL-10, IFN-gamma, TNF-alpha was not detected and only weak expression was found for RANTES (1/18). There was considerable variability between individual women, and women delivering preterm had lower levels of several cytokines in colostrum than women delivering at term. Yet, cytokine levels remained high months to years into lactation, providing immunological benefit to the breastfed infant/child.
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PMID:Cytokines in human milk. 889 39

The CC chemokine monocyte chemotactic protein-1 (MCP-1) was markedly elevated in the cerebrospinal fluid (CSF) of human immunodeficiency virus (HIV)-infected patients with cytomegalovirus (CMV) encephalitis. The MCP-1 CSF levels in CMV encephalitis were markedly higher than those in the CSF of HIV-infected patients with or without unrelated neurologic diseases, including progressive multifocal leukoencephalopathy, cryptococcal meningitis, toxoplasmic encephalitis, and primary lymphoma. Interleukin-8, RANTES, macrophage inflammatory protein (MIP)-1 alpha, and MIP-1 beta were not substantially increased in the CSF of CMV encephalitis patients. High levels of MCP-1 may underlie monocyte recruitment and tissue damage in CMV encephalitis and may represent a rapid and useful tool in the diagnostic armamentarium for neurologic disorders associated with HIV infection.
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PMID:Selective elevation of monocyte chemotactic protein-1 in the cerebrospinal fluid of AIDS patients with cytomegalovirus encephalitis. 889 15

Colony-stimulating factors are growth factors which induce differentiation of the hematopoietic stem cells. Granulocyte-macrophage colony-stimulating factor (GM-CSF) stimulates proliferation and improves functions of neutrophils and monocyte/macrophages. A macrophage submesothelial stratum has been suggested to constitute the first line of peritoneal defense. We have tested whether intraperitoneally administered GM-CSF could increase the number and activation of peritoneal macrophages in peritoneal dialysis patients. Eight stable patients injected 17 micrograms of GM-CSF in each of their four daily CAPD bags over three days. The clinical status, the peritoneal effluent and peripheral blood cell count, membrane receptor expression, phagocytosis activity and cytokine levels were monitored at days 0, 1, 3, 10 and 28. GM-CSF administration caused a large increase in peritoneal macrophage number (89-fold mean increase after 72 hr), returning to baseline seven days after withdrawal. GM-CSF triggered an increase in the expression of CD11b/CD18 (CR3) and its counterreceptor CD54, indicating the cellular progression into a more activated state. Both the number of phagocytic cells (55 +/- 15% to 83 +/- 10%, P < 0.05) and the phagocytic index (137 +/- 29 to 255 +/- 61, P < 0.01) were also augmented. Peritoneal effluent cytokine-chemokine levels demonstrated an increase in IL-6 and MCP-1 levels while TNF-alpha, IL-1, IL-8, MIP-1 alpha and RANTES were not significantly altered. GM-CSF administration did not affect the peritoneal transport of water or solutes. Minor side-effects were registered in two patients. In conclusion, intraperitoneal GM-CSF causes a marked and transient recruitment of primed macrophages into the peritoneum without inducing inflammatory parameters. GM-CSF should improve the peritoneal defensive capacity through potentiation of the effector functions of resident and newly-recruited macrophages.
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PMID:Immunomodulation of peritoneal macrophages by granulocyte-macrophage colony-stimulating factor in humans. 894 92


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