Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0043167 (pertussis)
 19,595 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Human granulocyte chemotactic protein 2 (GCP-2) has originally been isolated from cytokine-stimulated osteosarcoma cells as a chemokine coproduced in minute amounts together with interleukin 8. Human GCP-2 (75 residues) was synthesized on a 0.25-mmol scale using Fmoc chemistry. After disulfide bridge formation and purification, monomeric GCP-2 was recovered as a 6-kDa protein; the pure synthetic protein showed a molecular mass of 8076 Da as determined by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS). The exact amino acid sequence of synthetic GCP-2 was confirmed by Edman degradation. Synthetic GCP-2 was an equally active (minimal effective concentration of 1-3 nM) chemoattractant for neutrophilic granulocytes as was natural 75-residue GCP-2. At concentrations up to 30 nM, synthetic GCP-2 did not stimulate eosinophil, monocyte, or lymphocyte chemotaxis. GCP-2 induced a dose-dependent increase in [Ca2+]i in neutrophils, 1 nM being the minimal effective concentration. The GCP-2-induced [Ca2+]i increase was completely prevented by pertussis toxin. Prestimulation of neutrophils with equimolar concentrations of purified natural IL-8, GROalpha, GROgamma and ENA-78 abolished the [Ca2+]i increase in response to 1 nM GCP-2. Alternatively, the [Ca2+]i rise induced by these CXC chemokines was inhibited by pretreatment of neutrophils with GCP-2. GCP-2 stimulated [Ca2+]i increases in CXCR1- and CXCR2-transfected cells, demonstrating that GCP-2 binds to both IL-8 receptors. Intradermal injection of synthetic GCP-2 resulted in a dose-dependent neutrophil accumulation and plasma extravasation in rabbit skin. To provoke this skin reaction, GCP-2 (10 pmol/site) was nearly as effective as IL-8, indicating that it is an important complementary mediator of the inflammatory response.
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PMID:Characterization of synthetic human granulocyte chemotactic protein 2: usage of chemokine receptors CXCR1 and CXCR2 and in vivo inflammatory properties. 905 80

We studied the effects of serine proteases on cytokine gene expression by cultured normal human keratinocytes. In resting keratinocytes, steady-state mRNA levels for interleukins IL-1 alpha, IL-1 beta, IL-7, and IL-8, transforming growth factors alpha and beta, and tumor necrosis alpha were sufficient to be detected by our reverse transcriptase-polymerase clozin reaction method. Incubation of keratinocytes with 25 nM trypsin or 1 unit/ml thrombin for 24 hr selectively upregulated mRNA levels for granulocyte-macrophage colony-stimulating factor (GM-CSF) and Il-6 to detectable levels. Keratinocytes secreted GM-CSF and IL-6 protein in response to these proteases. Monensin did not inhibit the gene expression for the cytokines, thereby excluding the possibility of intervention by secreted molecules. Aprotinin and argatroban inhibited the effects of the proteases. SFLLRN and SLIGRL, tethered ligand receptor peptides for thrombin receptor and for proteinase-activated receptor 2 (PAR-2), respectively, duplicated the effects of the proteases on keratinocytes, which expressed mRNA for both receptors. Trypsin increased tyrosine phosphorylated proteins and intracellular free calcium concentrations. Tyrphostin, pertussis toxin, or H-7 suppressed trypsin- and thrombin-induced GM-CSF gene expression. Our results demonstrate that the serine proteases activate thrombin receptors and PAR-2 on keratinocytes, triggering intracellular signaling and then inducing the synthesis of GM-CSF. We speculate that serine proteases modulate the course of physiological and pathological processes in the skin by stimulating keratinocytes to produce the cytokines.
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PMID:Thrombin and trypsin induce granulocyte-macrophage colony-stimulating factor and interleukin-6 gene expression in cultured normal human keratinocytes. 906 88

The beta-chemokines monocyte chemotactic protein 1 (MCP-1), macrophage inflammatory protein 1 alpha (MIP-1alpha), MIP-1beta and regulated on activation, normal T cells, expressed and secreted (RANTES) induced the in vitro migration of the monocytic cell line MonoMac-6. MCP-1 exhibits the most potent chemotactic effect on this cell line while MIP-1alpha, RANTES and to a lesser extent MIP-1beta were more moderate inducers of cell migration. MonoMac-6 migration in response to chemokines was shown to be a chemotactic and not a chemokinetic response, which was inhibited by pertussis and cholera toxins suggesting a role for G proteins in chemokine receptor-mediated signalling in these cells; chemotaxis of MonoMac-6 cells in response to MCP-1 was abrogated by the addition of anti-MCP-1 antibody. The response of MonoMac-6 cells to the alpha-chemokines IL-8, IP-10, growth-related peptide (Gro) alpha and MIP-2beta was substantially weaker than to the beta-chemokines. MCP-1 caused an alteration in cellular morphology by increasing ruffling at the cell membrane and the number of cells exhibiting extended pseudopodia. The chemotactic response of MonoMac-6 cells to beta-chemokines was compared with less well-differentiated myelomonocytic cell lines. THP-1 showed a similar, but weaker response to the beta-chemokines while both HL60 and U937 failed to respond to any member of this subfamily when tested under the same conditions. These results suggest that the differentiation status of cells of monocytic lineage may affect their response to beta-chemokines.
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PMID:Migration responses of human monocytic cell lines to alpha- and beta-chemokines. 923 15

Activation of the serine/threonine kinase Akt, also called protein kinase B (PKB), was investigated in human neutrophils. Stimulation of the cells with the chemoattractant fMet-Leu-Phe or the chemokines IL-8 and GROalpha leads to the rapid and transient activation of PKB. Maximum PKB activation correlates with the well documented kinetics of respiratory burst and exocytosis. Wortmannin, a selective inhibitor of phosphoinositide 3-kinases (PI 3-kinases) in neutrophils, abrogates PKB activation. Similarly homo and heterotypic cross-linking of FcgammaIIA and FcgammaIIIB causes a transient activation of PKB that is sensitive to wortmannin treatment. Kinase activity measurements in immunoprecipitates from lysates of the myelocytic GM-1 cells or GM-1/CXCR1 cells, which are transfected with the IL-8 receptor 1, confirmed the transient activation of PKB observed in neutrophils. Stimulation of human monocytes with the CC chemokine RANTES (regulated on activation normal T cell expressed and secreted) also results in the activation of PKB. Preincubation of monocytes and neutrophils with Bordetella pertussis toxin inhibits fMet-Leu-Phe and RANTES-stimulated PKB activation, demonstrating that coupling of the receptors to heterotrimeric Gi-protein is required. The data show, that activation of PKB by Gi-protein-coupled receptors is mediated by PI 3-kinase and suggest that PKB is a constituent of neutrophil activating pathways.
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PMID:G-Protein-coupled receptors and Fcgamma-receptors mediate activation of Akt/protein kinase B in human phagocytes. 934 64

Modeling Salmonella-epithelial cell interaction in vitro has led to the realization that epithelial cells are crucial in orchestrating neutrophil (PMN) responses, in part by stimulating basolateral release of epithelial chemokines, including IL-8. However, such basolaterally released chemokines, while likely important in orchestration of PMN movement across the subepithelial matrix, are unlikely to be responsible for the final step of transepithelial migration of PMN and entry into the apical compartment. We now show that S. typhimurium attachment to T84 cell apical epithelial membranes induces polarized apical secretion of a pathogen-elicited epithelial chemoattractant (PEEC) bioactivity. Experiments employing semipurified PEEC indicate that it is released in a polarized apical fashion and is sufficient to explain the observed final step of transepithelial migration of PMN induced by Salmonella-apical membrane interaction. By preliminary physical characterization and profiles of PMN activation, PEEC appears to be a novel PMN chemotactic bioactivity. This 1- to 3-kDa nominal molecular mass chemokine-like bioactivity directly stimulates PMN via a pertussis toxin-sensitive receptor and elicits a Ca2+ signal. While these latter features are shared by most other chemokines, analysis of PEEC-elicited PMN activation reveals that, unlike these other agonists, PEEC, even at saturating concentrations, elicits chemotactic activity in the absence of stimulation of superoxide production and/or release of primary and/or secondary granules. These data suggest that the apically released PEEC activity appears to represent a novel epithelial-derived chemoattractant that directs PMN movement across epithelial monolayers.
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PMID:Apical secretion of a pathogen-elicited epithelial chemoattractant activity in response to surface colonization of intestinal epithelia by Salmonella typhimurium. 955 4

Interleukin-8 (IL-8) receptor A (CXCR1) couples to a pertussis toxin-sensitive G protein to mediate phospholipase Cbeta (PLCbeta) activation and cellular responses. Responses to CXCR1 are attenuated by prior exposure of neutrophils to either IL-8, a cleavage product of the fifth component of complement (C5a) or n-formylated peptides (formylmethionylleucylphenylalanine, fMLP). To characterize the role of receptor phosphorylation in the regulation of the CXCR1, a phosphorylation-deficient mutant, M2CXCR1, was constructed. This receptor, stably expressed in RBL-2H3 cells, coupled more efficiently to G protein and stimulated enhanced phosphoinositide hydrolysis, cAMP production, exocytosis, and phospholipase D activation, and was resistant to IL-8-induced receptor internalization. The rate and total amount of ligand stimulated actin polymerization remained unchanged, but interestingly, chemotaxis was decreased by approximately 30% compared with the wild type receptor. To study the role of receptor phosphorylation in cross-desensitization of chemoattractant receptors, M2CXCR1 was coexpressed with cDNAs encoding receptors for either fMLP (FR), C5a (C5aR), or platelet-activating factor (PAFR). Both C5aR and PAFR were cross-phosphorylated upon M2CXCR1 activation, resulting in attenuated guanosine 5'-3'-O-(thio)triphosphate (GTPgammaS) binding in membranes. In contrast, FR and M2CXCR1 were resistant to cross-phosphorylation and cross-inhibition of GTPgammaS binding by other receptors. Despite the resistance of M2CXCR1 to cross-phosphorylation and receptor/G protein uncoupling, its susceptibility to cross-desensitization of its Ca2+ response by fMLP and C5a, was equivalent to CXCR1. Regardless of the enhancement in certain receptor functions in M2CXCR1 compared with the wild type CXCR1, the mutated receptors mediated equivalent PLCbeta3 phosphorylation and cross-desensitization of Ca2+ mobilization by FR, C5aR, and PAFR. The results herein indicate that phosphorylation of CXCR1 regulates some, but not all of the receptors functions. While receptor phosphorylation inhibits G protein turnover, PLC activation, Ca2+ mobilization and secretion, it is required for normal chemotaxis and receptor internalization. Since phosphorylation of CXCR1 had no effect on its ability to induce phosphorylation of PLCbeta3 or to mediate class-desensitization, these activities may be mediated by independently regulated pathways.
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PMID:Multiple signaling pathways of human interleukin-8 receptor A. Independent regulation by phosphorylation. 955 32

Interleukin-8 (IL-8) and growth-related oncogene protein-alpha (GRO-alpha) belong to a family of alpha chemokines. The biologic effects of IL-8 are realized by binding to two seven-transmembrane receptors R1 and R2 and that of GRO-alpha by binding to receptor R2. Chinese hamster ovary (CHO) cells stably expressing R1 and R2 have been used to demonstrate that the ligand-dependent signaling by both receptors is via the inhibition of adenylyl cyclase. This inhibition is pertussis toxin sensitive and could be mediated by G(alpha)i2, which is present in CHO cells. GRO-alpha inhibits adenylyl cyclase exclusively in CHO-R2 cells, and IL-8 inhibits in both CHO-R1 and CHO-R2 cells. The cAMP status in cells is an easy, reliable, quantifiable signal that is amenable to high throughput screening for small molecule analogs.
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PMID:Inhibition of adenylyl cyclase by alpha chemokines IL-8 and GRO-alpha in Chinese hamster ovary cells expressing R1 and R2 receptors. 956 25

Most strains of Helicobacter pylori from patients with peptic ulcer disease or intestinal-type gastric cancer carry cagA, a gene that encodes an immunodominant protein of unknown function, whereas many of the strains from asymptomatically infected persons lack this gene. Recent studies showed that the cagA gene lies near the right end of a approximately 37kb DNA segment (a pathogenicity island, or PAI) that is unique to cagA+ strains and that the cag PAI was split in half by a transposable element insertion in the reference strain NCTC11638. In complementary experiments reported here, we also found the same cag PAI, and sequenced a 39 kb cosmid clone containing the left 'cagII' half of this PAI. Encoded in cagII were four proteins each with homology to four components of multiprotein complexes of Bordetella pertussis ('Ptl'), Agrobacterium tumefaciens ('Vir'), and conjugative plasmids ('Tra') that help deliver pertussis toxin and T (tumour inducing) and plasmid DNA, respectively, to target eukaryotic or prokaryotic cells, and also homologues of eukaryotic proteins that are involved in cytoskeletal structure. To the left of cagII in this cosmid were genes for homologues of HsIU (heat-shock protein) and Era (essential GTPase); to the right of cagII were homologues of genes for a type I restriction endonuclease and ion transport functions. Deletion of the cag PAI had no effect on synthesis of the vacuolating cytotoxin, but this deletion and several cag insertion mutations blocked induction of synthesis of proinflammatory cytokine IL-8 in gastric epithelial cells. Comparisons among H. pylori strains indicated that cag PAI gene content and arrangement are rather well conserved. We also identified two genome rearrangements with end-points in the cag PAI. One, in reference strain NCTC11638, involved IS605, a recently described transposable element (as also found by others). Another rearrangement, in 3 of 10 strains tested (including type strain NCTC11637), separated the normally adjacent cagA and picA genes and did not involve IS605. Our results are discussed in terms of how cag-encoded proteins might help trigger the damaging inflammatory responses in the gastric epithelium and possible contributions of DNA rearrangements to genome evolution.
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PMID:Analyses of the cag pathogenicity island of Helicobacter pylori. 959 95

An intact chemotactic response is vital for leukocyte trafficking and host defense. Opiates are known to exert a number of immunomodulating effects in vitro and in vivo, and we sought to determine whether they were capable of inhibiting chemokine-induced directional migration of human leukocytes, and if so, to ascertain the mechanism involved. The endogenous opioid met-enkephalin induced monocyte chemotaxis in a pertussis toxin-sensitive manner. Met-enkephalin, as well as morphine, inhibited IL-8-induced chemotaxis of human neutrophils and macrophage inflammatory protein (MIP)-1alpha, regulated upon activation, normal T expressed and secreted (RANTES), and monocyte chemoattractant protein 1, but not MIP-1beta-induced chemotaxis of human monocytes. This inhibition of chemotaxis was mediated by delta and micro but not kappa G protein-coupled opiate receptors. Calcium flux induced by chemokines was unaffected by met-enkephalin pretreatment. Unlike other opiate-induced changes in leukocyte function, the inhibition of chemotaxis was not mediated by nitric oxide. Opiates induced phosphorylation of the chemokine receptors CXCR1 and CXCR2, but neither induced internalization of chemokine receptors nor perturbed chemokine binding. Thus, inhibition of chemokine-induced chemotaxis by opiates is due to heterologous desensitization through phosphorylation of chemokine receptors. This may contribute to the defects in host defense seen with opiate abuse and has important implications for immunomodulation induced by several endogenous neuropeptides which act through G protein-coupled receptors.
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PMID:Opiates transdeactivate chemokine receptors: delta and mu opiate receptor-mediated heterologous desensitization. 967 44

The homing of lymphocytes to secondary lymphoid organs is thought to involve the action of chemokines. Secondary lymphoid-tissue chemokine (SLC), a high endothelial venule (HEV)-associated chemokine, has emerged as a candidate for participating in this process. We now show that immobilized SLC strongly induces beta2 integrin-mediated binding of T lymphocytes of naive phenotype and B lymphocytes to ICAM-1 under static conditions. This effect is not mediated by beta2 integrin affinity modulation, because SLC does not elicit a beta2 integrin activation epitope (mAb24) on naive T lymphocytes. In a parallel plate flow chamber, lymphocytes rolling via L-selectin are rapidly arrested through beta2 integrins in a pertussis toxin-sensitive manner on a substrate consisting of L-selectin ligands (peripheral lymph node addressins) together with ICAM-1 and SLC. Naive T lymphocytes are arrested on the HEV substrate with sixfold higher efficiency than memory cells. Neutrophils roll, but are not arrested by SLC, whereas they respond to immobilized IL-8 with rapid arrest. Thus, our artificial HEV system recapitulates critical features of lymphocyte interactions with HEV in vivo. These observations strongly point to the participation of SLC in homing of lymphocytes to secondary lymphoid organs.
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PMID:A high endothelial cell-derived chemokine induces rapid, efficient, and subset-selective arrest of rolling T lymphocytes on a reconstituted endothelial substrate. 983 23


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