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)

Corticosteroids are the most effective drugs in the management of asthma. However, because of their known side effects and the existence of corticosteroid-resistant patients, there is a need for substitute medications in asthma therapy. Using cell lines, in the present study, the two corticosteroids dexamethasone (Dex), and beclomethasone (Bec), as well as the immunosuppressant cyclosporin A (CsA), and the antimetabolic drug methotrexate (Mtx) were examined in their effect on release of immunoreactive IL-1 beta, IL-2, IL-4, IL-5, and IL-8. THP-1 cells served as a test model for monocytes secreting IL-1 beta and IL-8 upon stimulation by lipopolysaccharide. Jurkat cells were used as a test model for TH1-type T-cells and were stimulated for IL-2 release with a combination of phytohemagglutinin and phorbol myristate acetate. Representing TH2-type T-cells, D10.G4.1 cells challenged by anti-CD3-mAb produced IL-4, and IL-5. Considerable qualitative and quantitative differences in the relative efficacy of the test compounds were found. Following IC50 values (nmol/l) of the test compounds were estimated (IL-1 beta/IL-8/IL-2/IL-4/IL-5): Dex (10.8/35.7/ > 10,000.0/5.1/4.1), Bec (30.9/102.2/8591.4/0.6/0.4), and CsA (318.7/6211.2/2.3/68.2/237.9). Mtx in concentrations up to 10,000.0 nmol/l was completely inactive. It can be concluded that corticosteroids show another inhibition pattern than CsA: corticosteroids affect mainly TH2-type T-cells, while CsA primarily inhibits the TH1-type T-cell response.
 ...
PMID:Effect of corticosteroids, cyclosporin A, and methotrexate on cytokine release from monocytes and T-cell subsets. 807 Oct 57

Interleukin-8 (IL-8), a neutrophil chemoattractant and activating cytokine, has been implicated as a proinflammatory mediator in gram-negative sepsis. In vitro data support the notion of IL-8 as an endothelial adherence inhibitor. To evaluate this issue, we infused six volunteers with reference endotoxin and measured plasma levels of IL-8, neutrophil tumor necrosis factor alpha (TNF-alpha) receptors, TNF-alpha-induced adherence to fibronectin, and neutrophil chemotaxis to IL-8 and other attractants. We found that, at 3 h postinfusion, IL-8 but not TNF-alpha plasma levels were elevated. Neutrophils had shed L-selectin (mean channel fluorescence decrease, 79 +/- 9 to 49 +/- 7; P = 0.0625) and TNF-alpha receptors (decrease in number of receptors per cell, 1,596 +/- 340 to 574 +/- 93; P = 0.004). Cells were chemotactically desensitized to IL-8. TNF-alpha-induced adherence to fibronectin was suppressed from 69% +/- 5% of the phorbol myristate acetate response to 38% +/- 7% (P = 0.0154). These findings support the notion that release of IL-8 into the vascular space may be an in vivo mechanism for suppression of neutrophil accumulation at extravascular sites. L-Selectin loss would reduce the ability of neutrophils to adhere to activated endothelial cells. The specific loss of migratory response to IL-8 would impair neutrophil delivery to areas where IL-8 was the predominant chemoattractant. Loss of TNF-alpha-induced adherence to fibronectin would blunt those responses, including production of oxidants, capacitated by adherence.
 ...
PMID:Alterations of neutrophil responses to tumor necrosis factor alpha and interleukin-8 following human endotoxemia. 811 67

Incubation of polymorphonuclear leukocytes with chemoattractants, granulocyte-macrophage colony-stimulating factor (GM-CSF), or phorbol 12-myristate 13-acetate (PMA) activated both mitogen-activated protein kinase kinase (MAPKK) and mitogen-activated protein kinase (MAPK). Activation by chemoattractants was rapid and transient, being maximal by 1 min and decreasing by 10 min. The order of efficacy was formyl-met-leu-phe > C5a > > LTB4 > interleukin 8 > platelet-activating factor. In contrast, activation by GM-CSF or PMA was slow and sustained being maximal at 5 min and with little decrease by 30 min. Sustained MAPK activation required continuous activation of the MAPKK. The MAPKK induced by N-formylmethionyl-leucyl-phenylalanine, GM-CSF, or PMA was resolved into two forms by anion exchange chromatography (Mono Q). Both corresponded to a 45-kDa MAPKK antigen by Western blotting and were inactivated by serine/threonine protein phosphatase 2A. Rechromatography of both forms after dephosphorylation resulted in the antigen's eluting slightly earlier on the Mono Q gradient than when in the active state. However, the two peaks remained separate, suggesting that they are not merely different phosphoforms of the same enzyme. The MAPK cascade is a signaling pathway common to many polymorphonuclear leukocyte stimulants, which may be activated transiently or in a sustained manner.
 ...
PMID:Characterization of two different forms of mitogen-activated protein kinase kinase induced in polymorphonuclear leukocytes following stimulation by N-formylmethionyl-leucyl-phenylalanine or granulocyte-macrophage colony-stimulating factor. 814 33

Pro-inflammatory cytokines mediate their biological functions after they are secreted or released from intracellular to extracellular milieu. Keratinocytes have proven to be able to produce various cytokines including IL-1 and IL-8. Dysregulations of IL-1 and IL-8 were found in psoriatic lesions. Recently, vitamin D3 (VD3) was found to be an effective and safe therapy for psoriasis. In the present study, we investigated the effects of 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) and its analogue MC903 on IL-1 alpha and IL-8 secretion by human keratinocytes in vitro. Cultured normal human keratinocytes (NHKs) produced considerable amounts of IL-1 alpha but secreted less. In contrast, they produced less IL-8 and almost all molecules were secreted to the culture supernatants. Treatment of unstimulated NHKs with 1,25(OH)2D3 or MC903 showed little effects on IL-1 alpha production and secretion though they slightly enhanced IL-8. When NHKs were stimulated with tumour necrosis factor-alpha (TNF alpha), both IL-1 alpha and IL-8 secretions were enhanced and these enhancements were inhibited by 1,25(OH)2D3 or MC903. Stimulation of NHKs with phorbol 12-myristate 13-acetate(PMA) and lipopolysaccharide(LPS) resulted in an increase of IL-8 and decrease of IL-1 alpha in the culture supernatants. Addition of 1,25(OH)2D3 or MC903 inhibited the increased secretion of IL-8 but restored decreased secretion of IL-1 alpha from stimulated NHKs dose dependently. Hydrocortisone and cyclosporin A showed similar inhibitory effects on PMA/LPS-increased IL-8 secretion from NHKs but had little effect of restoring IL-1 alpha.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Regulatory effects of 1,25-dihydroxyvitamin D3 and a novel vitamin D3 analogue MC903 on secretion of interleukin-1 alpha (IL-1 alpha) and IL-8 by normal human keratinocytes and a human squamous cell carcinoma cell line (HSC-1). 819 81

In this study, we demonstrate that mononuclear cells of human milk have a potential for production of many different cytokines. We applied a technique for cytokine detection at the single-cell level using cytokine specific MAb and immunofluorescence. The characteristic staining pattern obtained represents intracellular cytokine production, which allows for the assessment of the cellular origin of production. Milk mononuclear cells were mitogen-stimulated in vitro and cultured for 4 h and then stained for 13 cytokines. Lipopolysaccharide stimulation induced extensive production of the following monokines: IL-1 alpha, IL-1 beta, IL-1ra, IL-6, IL-8, and tumor necrosis factor-alpha. IL-10 and granulocyte-macrophage colony-stimulating factor were smaller products, although detectable in most samples. The abundant monokine production correlated with the high number of macrophages in milk. Spontaneous monokine production in unstimulated cells could be detected in six out of 11 samples. The highest incidence was evident for IL-8. No spontaneous lymphokine production was detected. Considering the low proportion of lymphocytes, stimulation with phorbol myristate acetate in combination with ionomycin resulted in considerable production of the following lymphokines: IL-2, IL-3, IL-4, IL-10, interferon-gamma, tumor necrosis factor-alpha. Macrophages contributed to the high production of tumor necrosis factor-alpha and GM-CSF. IL-5 synthesis was detectable in only one sample. This work reveals that human milk mononuclear cells are potent producers of cytokines when mitogen stimulated in vitro. The in vivo implications of these findings remain to be investigated further.
 ...
PMID:Cytokine production in mononuclear cells of human milk studied at the single-cell level. 823 27

The regulation of IL-6 mRNA expression was studied in human blood monocytes and in the human epidermoid carcinoma cell line HEp-2. In human monocytes phorbol-12-myristate 13-acetate (PMA) did not induce IL-6 but it increased IL-1 beta and IL-8 mRNA levels. Furthermore, in monocytes, protein kinase C (PKC) activation by PMA even reduced IL-1-induced IL-6 mRNA, and IL-1-induced IL-6 synthesis was increased by the PKC inhibitor staurosporine. IL-6 synthesis in HEp-2 cells was induced by IL-1, PMA, and calcium ionophore A 23187 but not by dibutyryl-cAMP. PMA-, but not IL-1-induced IL-6 synthesis in HEp-2 cells was inhibited by staurosporine. PMA pretreatment of HEp-2 cells abolished PMA-induced IL-6 but the IL-1 effect was not reduced. These data indicate that IL-6 can be induced by a PKC-independent pathway in monocytes and HEp-2 cells. In monocytes PKC activation does not induce IL-6 and PMA interferes with the IL-1 effect. Transcription factors known to be involved with the regulation of IL-6 expression were studied by gel retardation assays. NF-IL-6 and AP-1 activity were constitutively expressed in monocytes and HEp-2 cells under conditions where IL-6 mRNA was not detectable and levels did not change in response to stimulation by IL-1 or PMA. In contrast, NF-kB was increased by both IL-1 and PMA, but only the effect of PMA, and not that of IL-1, was inhibited by staurosporine. In summary, these results show tissue-specific differences in the regulation of IL-6 expression. Induction of IL-6 in monocytes is PKC independent. In the epithelial cell line HEp-2 IL-6 is inducible by PKC as well as by a PKC-independent pathway.
 ...
PMID:Regulation of interleukin-6 (IL-6) expression: evidence for a tissue-specific role of protein kinase C. 824 77

Bactericidal/permeability-increasing protein (BPI) is a major component of the granules of polymorphonuclear neutrophils (PMNs) and is involved in the killing of gram-negative bacteria. A 23-kd recombinant protein, corresponding to the NH2-terminal fragment of human BPI (rBPI23), has been shown to bind lipid A and antagonize some lipopolysaccharide (LPS)-mediated effects. In this study the ability of rBPI23 to prevent a wide range of cellular responses to LPS was investigated. In vitro assays were carried out using human blood to more closely approximate in vivo conditions. The release of proinflammatory cytokines [tumor necrosis factor (TNF), interleukin-1 beta (IL-1 beta), IL-6, IL-8], induced by E. coli O113 LPS, was markedly reduced by rBPI23 in a concentration-dependent fashion. The production of the anti-inflammatory protein IL-1ra (IL-1 receptor antagonist) was triggered by lower LPS concentrations than those necessary for the other cytokines. Furthermore, prevention of IL-1ra release required higher rBPI23 concentrations than for other cytokines. The LPS-induced production of oxygen-derived free radicals by phagocytic cells (resulting in chemiluminescence) was also prevented by rBPI23. The inhibition was specific for LPS because the activation of leukocytes by phorbol myristate acetate, zymosan, or TNF was unaffected by BPI. The ability of rBPI23 to antagonize specifically the effects of endotoxin in the complex environment of human blood along with its bactericidal activity suggests that rBPI23 may be a novel therapeutic agent in the treatment of gram-negative infections.
 ...
PMID:A recombinant amino terminal fragment of bactericidal/permeability-increasing protein inhibits the induction of leukocyte responses by LPS. 824 7

The cell line AG-F was isolated from the marrow of a neuroblastoma patient undergoing myeloablative treatment and autologous bone marrow rescue. A year later, the patient developed a Hodgkin's type lymphoma. AG-F cell line demonstrated an unusual phenotype, lacking surface CD2 and CD3, but expressing high levels of CD4, CD5, CD7, CD29, and CD45RO. Markers associated with Hodgkin's lymphoma cells, CD15 and CD30, were also positive. AG-F cells grow in suspension in clusters of 50-200 cells, with a doubling time of 9 h. They can also grow in serum-free medium and form tumors in nude mice. AG-F cells have amplified N-myc and c-myc and high levels of the corresponding mRNA transcripts. Cytogenetic analysis revealed a DNA index by flow cytometry of near tetraploid cells and a karyotype of 85-87 chromosomes, with consistent abnormalities in chromosomes 1, 5, and 9. Gene rearrangement studies revealed rearrangement of the beta gene of the T-cell receptor. AG-F cells secrete high levels of IL-6, IL-8, IL-10, and GM-CSF. Cell adherence and formation of long processes could be induced by fibronectin and were enhanced by exposure to PMA. Cells exposed to phorbol myristate acetate (PMA) had increased expression of CD11a, CD11b, CD18, CD45RO, and HLA-DR, whereas expression of CD15 and CD30 was markedly decreased. Similarly, the level of c-myc and N-myc oncoproteins and the levels of the cytoskeletal proteins, actin, tubulin, and vimentin markedly decreased early after PMA-induced differentiation.
 ...
PMID:Isolation and characterization of an early T-helper/inducer cell line with a unique pattern of surface phenotype, constitutive cytokine secretion and myc oncogene expression. 825 4

Changes in cytosolic free Ca2+ influence important granulocyte functions like chemotactic behavior, adherence to endothelia, and phagocytosis. In the following study we used a simple reproducible procedure involving flow cytometry in combination with the fluorescent dye Fluo-3 to measure Ca2+ changes in human granulocytes. The aim of our study was to investigate the involvement of protein kinase C in regulating cytosolic free Ca2+ concentrations after stimulation of cells with IL-8 and fMLP. Both reagents induced a 5-6 fold increase in cytosolic Ca2+. Experiments conducted in Ca(2+)-free media showed a minor 18-29% decrease in cytosolic Ca2+ response, suggesting that intracellular Ca(2+)-stores are the main source for Ca2+ release after fMLP or IL-8 stimulation. Activators of protein kinase C, phorbol myristate acetate (PMA) and 1-oleyl-2-acetyl-sn-glycerol (OAG), inhibited cytosolic Ca(2+)-increase completely when induced by IL-8 and by 68-82% in the case of fMLP. Staurosporine, an inhibitor of protein kinase C, was able to attenuate or even abolish the PMA/OAG-effect. Our results show that changes in cytosolic Ca2+ due to IL-8 and fMLP signalling can be regulated by protein kinase C in human granulocytes. This regulatory role of protein kinase C involves some form of receptor modulation (i.e. phosphorylation, internalization, shedding).
 ...
PMID:Protein kinase C regulates IL-8 and fMLP induced cytoplasmic Ca2+ increase in human granulocytes by receptor modulation measurements by flow cytometry. 826 89

The expression and regulation of seven human members of a family of related cytokines, which play a role as effectors of inflammation, were analysed in hemopoietic cells and in fibroblasts. In T lymphocytes all genes: platelet basic protein (PBP); platelet factor 4 (PF-4); IL-8/NAP-1; IP-10; GRO; pAT464 and pAT744 were induced by stimulation with phytohemagglutinin and phorbol 12-myristate 13-acetate (PHA/PMA). In contrast to T cells, only some of the genes were induced upon terminal differentiation of pro-monocytic cells and upon serum stimulation of resting fibroblasts. This distinct expression indicates functional differences of the individual proteins. The expression of inflammatory mediators in fibroblasts suggests the involvement of these cells in inflammatory reactions.
 ...
PMID:Cell type specific expression of members of the IL-8/NAP-1 gene family. 833 26


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>