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)

This study examines the ability of HT-29 human colonic epithelial cells to stimulate neutrophil migration and adhesion. Interleukin-8 (IL-8), a potent neutrophil chemoattractant, was detected in conditioned media from both unstimulated (1.1 ng/ml) and IL-1 beta-stimulated (16.1 ng/ml) HT-29 cultures. Conditioned medium from IL-1 beta-exposed HT-29 cells stimulated neutrophil migration (395% of control, P < 0.01), and this effect was completely inhibited by anti-IL-8 antibody. HT-29 medium also induced shedding of neutrophil L-selectin and increased expression of neutrophil CD11/CD18 adhesion receptors. Coculture of HT-29 cells with human endothelial cell monolayers resulted in increased neutrophil transendothelial migration (169% of control, P < 0.01), which was blocked by both anti-IL-8 and anti-CD18 antibody. Northern hybridization analysis demonstrated increased levels of mRNA for IL-8 and intercellular adhesion molecule-1 (ICAM-1) in cytokine-treated HT-29 cells. Cytokine stimulation of HT-29 monolayers was also associated with increased neutrophil adhesion to these cells. Neutrophil-HT-29 cell adhesion was blocked by monoclonal antibodies to neutrophil CD18 or to ICAM-1 on the HT-29 cells (86% and 56% inhibition, respectively, P < 0.01 for both). These data suggest that IL-8 secretion by activated colonic epithelial cells may contribute to neutrophil extravasation and tissue infiltration in intestinal inflammation.
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PMID:IL-8 secretion and neutrophil activation by HT-29 colonic epithelial cells. 781 Jun 67

Neutrophil adhesion and direct cytotoxicity for cardiac myocytes require chemotactic stimulation and are dependent upon CD18-ICAM-1 binding. To characterize the potential role of IL-8 in this interaction, canine IL-8 cDNA was cloned and the mature recombinant protein expressed in Escherichia coli BL21 cells. Recombinant canine IL-8 markedly increased adhesion of neutrophils to isolated canine cardiac myocytes. This adhesion resulted in direct cytotoxicity for cardiac myocytes. Both processes were specifically blocked by antibodies directed against CD18 and IL-8. In vivo, after 1 h of coronary occlusion, IL-8 mRNA was markedly and consistently induced in reperfused segments of myocardium. IL-8 mRNA was not induced in control (normally perfused) myocardial segments. Minimal amounts of IL-8 mRNA were detected after 3 or 4 h of ischemia without reperfusion. Highest levels of induction were evident in the most ischemic myocardial segments. IL-8 mRNA peaked in the first 3 h of reperfusion and persisted at high levels beyond 24 h. IL-8 staining was present in the inflammatory infiltrate near the border between necrotic and viable myocardium, as well as in small veins in the same area. These findings provide the first direct evidence for regulation of IL-8 in ischemic and reperfused canine myocardium and support the hypothesis that IL-8 participates in neutrophil-mediated myocardial injury.
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PMID:Interleukin-8 gene induction in the myocardium after ischemia and reperfusion in vivo. 781 50

The present study was aimed at characterizing the effects of in vitro exposure to GM-CSF on blood monocytes and tumor-associated macrophages (TAM) in human ovarian cancer. Purified populations of TAM from ovarian cancer patients were studied in terms of expression of surface molecules, cytokine production and tumor cytotoxicity after overnight incubation with GM-CSF or IFN gamma and LPS, used as reference activators. GM-CSF augmented the surface expression of ICAM-I and CD18 in TAM and in blood monocytes. Stimulation was more prominent in monocytes than in TAM, which showed higher baseline expression of this adhesion molecule. ICAM-3 was not influenced by GM-CSF or by IFN gamma/LPS. GM-CSF-augmented ICAM-I expression was associated with higher levels of mRNA transcripts. The protein synthesis inhibitor cycloheximide super-induced basal and GM-CSF-induced ICAM-I transcripts, thus excluding a role for secondary polypeptide mediators. In the absence of stimuli, TAM produced higher levels, compared to monocytes, of IL-6 and IL-8 but not of IL-1 and TNF. GM-CSF augmented the production of IL-6 and IL-8 (but not that of IL-1 and TNF) in TAM, whereas it had little effect on blood monocyte. Tumoricidal activity was tested against two ovarian tumor cell lines (OVCAR3 and SW626). GM-CSF more prominently augmented monocyte cytotoxicity, while only 2 of 6 TAM preparations were stimulated by GM-CSF. These results suggest that GM-CSF selectively regulates the function of blood monocytes and TAM, the effect of this cytokine varying with the parameter and cell population examined. These data provide a rational and biological endpoint for further studies with GM-CSF as an activator of mononuclear phagocyte function in ovarian cancer.
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PMID:Effects of granulocyte-monocyte colony-stimulating factor (GM-CSF) on expression of adhesion molecules and production of cytokines in blood monocytes and ovarian cancer-associated macrophages. 782 34

Physiological levels of human fibrinogen markedly inhibited the chemotactic activity of human neutrophils triggered by zymosan-activated serum (ZAS), C5a, or IL-8 in a Boyden chamber assay. Fibrinogen also slightly inhibited the N-formyl-methionyl leucyl-phenylalanine (FMLP)-induced migration of human neutrophils. Albumin was devoid of the inhibitory activities displayed by fibrinogen in this system. The inhibition of chemotaxis by fibrinogen was dose-dependent and saturable. Fibrinogen placed in the upper compartment of the Boyden chamber produced a larger inhibition than that obtained with fibrinogen placed in the lower compartment. Lysine as well as the lysine analog 6-aminohexanoic acid (AHA) decreased the inhibitory capacity of fibrinogen. In contrast, both arginine and glutamine failed to suppress the fibrinogen-mediated inhibition of neutrophil chemotaxis. AHA counteracts the inhibition of ZAS-induced chemotaxis by anti-CD18 monoclonal antibody, suggesting that lysine binding sites are required for integrin function in chemotaxis. Fibrinogen also inhibited, in a dose-dependent manner, the oxygen consumption of neutrophils activated by opsonized zymosan. Taken together, the present results indicate that fibrinogen modulates neutrophil functions and suggest that in addition to its role in blood coagulation, circulating fibrinogen may be involved in regulation of the inflammatory response.
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PMID:Inhibition of neutrophil activation by fibrinogen. 784 97

Recently, we described the cloning and expression of a human cDNA which is the homologue to P600, a gene transcribed by mouse Th2 clones. Based on its activities on human monocytes and B cells this gene was designated IL-13. In the present study we investigated the effects of IL-13 alone or in combination with IL-4, IFN-gamma, or IL-10 on human monocytes. IL-13 induced significant changes in the phenotype of monocytes. Like IL-4, it enhanced the expression of CD11b, CD11c, CD18, CD29, CD49e (VLA-5), class II MHC, CD13, and CD23, whereas it decreased the expression of CD64, CD32, CD16, and CD14 in a dose-dependent manner. IL-13 induced up-regulation of class II MHC Ag and its down-regulatory effects on CD64, CD32, and CD16 expression were prevented by IL-10. IFN-gamma could also partially prevent the IL-13-induced down-regulation of CD64, but not that of CD32 and CD16. However, IL-13 strongly inhibited spontaneous and IL-10- or IFN-gamma-induced ADCC activity of human monocytes toward anti-D coated Rh+ erythrocytes, indicating that the cytotoxic activity of monocytes was inhibited. Furthermore, IL-13 inhibited production of IL-1 alpha, IL-1 beta, IL-6, IL-8, IL-10, IL-12 p35, IL-12 p40, macrophage inflammatory protein-1 alpha, granulocyte/macrophage-CSF, granulocyte-CSF, IFN-alpha, and TNF alpha by monocytes activated with LPS. In contrast, IL-13 enhanced the production of IL-1 ra by these cells. Similar results on cytokine production were observed or have been obtained with IL-4. Thus IL-13 shares most of its activities on human monocytes with IL-4, but no additive or synergistic effects of IL-4 and IL-13 on human monocytes were observed, suggesting that these cytokines may share common receptor components. Taken together, these results indicate that IL-13 has anti-inflammatory and important immunoregulatory activities.
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PMID:Effects of IL-13 on phenotype, cytokine production, and cytotoxic function of human monocytes. Comparison with IL-4 and modulation by IFN-gamma or IL-10. 790 77

We have compared and quantitated transendothelial migration of neonatal neutrophils (N-PMNs) and adult bovine peripheral-blood PMNs (A-PMNs) in vitro using monolayers of endothelium and a two-chamber apparatus. Bovine aortic endothelial cells were cultured to confluence on polycarbonate filters perforated with 3.0-micron-diameter pores. 51Cr-labeled PMNs were added to the upper chamber, with or without an anti-CD18 antibody (monoclonal antibody 60.3). Chemotactic stimuli in the lower chambers included recombinant human interleukin-8 (rhIL-8; 75 ng/ml), rhC5a (10(-7) M), and zymosan-activated bovine serum (ZAS; 10%). At 60 min incubation with rhIL-8, greater numbers (P < .01) of N-PMNs (24.70 +/- 5.95%) than of A-PMNs (15.77 +/- 3.66%) had migrated across the endothelial barrier, and a similar difference was present at 90 min. Migration rates of N-PMNs and A-PMNs were similar (P > .05) at all time points when using rhC5a and ZAS as stimuli. Anti-CD18 monoclonal antibody significantly decreased migration (P < .01) of both N-PMNs and A-PMNs to low levels when IL-8 and ZAS were used as stimuli. Because leukocyte integrin expression on PMNs affects transendothelial migration, we also compared surface expression of CD18, CD11a, and CD11c on PMNs from the two age groups. We found no significant quantitative differences in integrin expression between PMNs from the two age groups, regardless of whether the PMNs were incubated with buffer alone or with chemotaxins (rhIL-8, rhC5a, ZAS).
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PMID:Transendothelial migration of neonatal and adult bovine neutrophils in vitro. 790 94

1. Uropathogenic E. coli adhere to mucosal sites. 2. In the urinary tract, adherence is followed by inflammation, including a mucosal cytokine response. 3. Bacteria activate epithelial cells to secrete IL-6 and IL-8. IL-6 may cause the fever and acute phase response that accompany systemic urinary tract infections. IL-8 may function as a neutrophil chemoattractant. 4. E. coli up-regulate adhesion molecule expression on epithelial cell lines and neutrophil migration through epithelial cell monolayers. This process is inhibited by antibodies to CD18 and ICAM-1. 5. Cytokines released by nonepithelial cells (T cells and monocytes) modify the epithelial cell cytokine response to bacteria.
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PMID:Bacterial adherence and mucosal cytokine production. 791 93

Expression of mRNA for the neutrophil (PMN) chemokine, KC, in rat models of lung injury suggests a role for this chemokine in pulmonary inflammation. We addressed this hypothesis at the protein level by functionally characterizing recombinant rat KC (rKC) in vitro and in vivo. In vitro, rKC induced PMN chemotaxis and increased the expression of CD11b/CD18 on PMNs. Recombinant KC also induced a respiratory burst (quantitated by flow cytometry) in rat PMNs, similar to that caused by its human structural homologue, gro/melanoma growth-stimulating activity, on human PMNs, but less than that caused by IL-8 on human PMNs. Intratracheal instillation of rKC induced dose-dependent PMN influx into airspaces (average PMNs in bronchoalveolar lavage: vehicle = 1.5%, n = 4; rKC (1 microgram) = 11.5%, n = 2; rKC (10 micrograms) = 77.3%, n = 2). A neutralizing anti-KC Ab reduced the chemotactic activity of rat bronchoalveolar lavage fluid collected after the intratracheal administration of LPS (48.3 +/- 8% of control, n = 4). Anti-KC neutralizing Ab markedly inhibited PMN accumulation (71 +/- 6%) within the lungs in response to an intratracheal challenge of LPS. We conclude that rat KC is a major but not exclusive mediator of PMN activation and recruitment during LPS-induced pulmonary inflammation.
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PMID:Functional characterization of the rat chemokine KC and its importance in neutrophil recruitment in a rat model of pulmonary inflammation. 799 53

Endotoxin [lipopolysaccharide (LPS)] is a potent inflammatory stimulus and can activate human umbilical vein endothelium (HUVE) for leucocyte adhesiveness and transendothelial migration. Here we investigated the role of HUVE-secreted cytokines in this process. When HUVE monolayers were grown on filters and preincubated for 3 hr with LPS, 51Cr-labelled polymorphonuclear leucocytes (PMNL) migrated across the HUVE in a dose- and time-dependent manner. Maximal PMNL transmigration with LPS (1 ng/ml) was 26 +/- 3% of added PMNL in 75 min. Neutralizing antibodies to interleukin-1 alpha (IL-1 alpha) and IL-1 beta, tumour necrosis factor-alpha (TNF-alpha), IL-8 or recombinant IL-1 receptor antagonist had no effect on the activation by LPS of the HUVE for supporting migration of PMNL. The HUVE 'activated state' declined with prolonged (22 hr) exposure to LPS, as reflected by a decrease in PMNL transendothelial migration to 5.5 +/- 1% and in the expression of the endothelial cell adhesion molecule, E-selectin, as compared to stimulation with LPS for 3 hr. However, simultaneous exposure to interferon-gamma (IFN-gamma) (200 IU/ml) and LPS maintained maximal PMNL transendothelial migration (28 +/- 4%) for at least 24 hr, prolonged E-selectin expression by HUVE and superinduced intracellular adhesion molecule-1 (ICAM-1) expression. The PMNL transendothelial migration was blocked by > 90% by monoclonal antibody (mAb) to CD18 with either 3 hr of LPS or 22 hr LPS + IFN-gamma stimulation. Migration was partially inhibited by mAb to E-selectin (30-40%) or to ICAM-1 (35-45%) and by a combination of both reagents (50-60%) under both stimulation conditions. Thus, LPS activation of HUVE for PMNL transendothelial migration: (a) does not require secretion of IL-1, TNF-alpha or IL-8 by the endothelium, (b) IFN-gamma enhances and prolongs endothelial activation by LPS and may increase leucocyte infiltration in LPS or bacterial inflammatory reactions, and (c) CD18-dependent mechanisms are equally important for PMNL transendothelial migration under both acute (3 hr) and prolonged (22 hr LPS + IFN-gamma) activation of endothelium.
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PMID:Endotoxin activation of endothelium for polymorphonuclear leucocyte transendothelial migration and modulation by interferon-gamma. 810 89

Recent evidence suggests that phospholipase A2 (PLA2)-derived lipid mediators may regulate a number of neutrophil responses including degranulation and adhesion. In view of the potential role of PLA2 in stimulus-secretion coupling, we examined the relationship between PLA2 activation and the surface expression of CD11b/CD18 (MAC-1) in human polymorphonuclear leukocytes (hPMNL), including the functional consequences of PLA2 inactivation on MAC-1-dependent adhesion. The selective inhibition of PLA2 by the marine natural products manoalide (MLD) and scalaradial (SLD) blocks [3H]arachidonic acid (AA) release in calcium ionophore A23187-stimulated neutrophils, and also inhibits secretion of specific and azurophilic granule constituents. Additional studies demonstrate that MLD, SLD, and other less potent PLA2 inhibitors such as 4-bromophenacylbromide and nordihydroguiaretic acid inhibit the surface expression of MAC-1 (IC50: MLD, 0.33 microM; SLD, 0.23 microM; 4-bromophenacylbromide, 2.8 microM; NDGA, 3.5 microM) at concentrations similar to those at which they inhibit [3H]AA release. Inhibitors of cyclooxygenase, 5-lipoxygenase, protein kinase C, or calcium channel antagonists have no effect on MAC-1 expression. PLA2 inactivation also prevents MAC-1 up-regulation in hPMNL stimulated with FMLP, IL-8, TNF-alpha, PMA, or platelet activating factor. In FMLP-stimulated hPMNL, under conditions in which no secondary granule constituents are secreted, MAC-1 and alkaline phosphatase up-regulation from intracellular granules is inhibited by MLD and SLD. Functional assays also demonstrate that MLD and SLD block MAC-1-dependent adhesion of activated neutrophils to keyhole limpet hemocyanin at concentrations that block the surface expression of MAC-1. [3H]AA release and MAC-1 expression in MLD and SLD-treated hPMNL could be recovered in the presence of 1 mM hydroxylamine in a time-dependent fashion, consistent with reported data that MLD and SLD inactivate PLA2 through Schiff base formation. In summary, these data emphasize the role of PLA2 as a key regulator of MAC-1 expression in models of neutrophil adhesion.
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PMID:Regulation of CD11b/CD18 expression in human neutrophils by phospholipase A2. 822 53


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