interleukin-8 and Leukemia--Monocytic--Acute

Treponema pallidum is the pathogen that causes syphilis, a sexually transmitted disease; however, the pathogenic mechanism of this organism remains unclear. Tp92 is the only T. pallidum outer membrane protein that has structural features similar to the outer membrane proteins of other Gram-negative bacteria, but the exact functions of this protein remain unknown. In the present study, we demonstrated that the recombinant Tp92 protein can induce human mononuclear cell death. Tp92 mediated the human monocytic cell line derived from an acute monicytic leukemia patient (THP-1) cell death by recognizing CD14 and/or TLR2 on cell surfaces. After the stimulation of THP-1 cells by the Tp92 protein, Tp92 may induce atypical pyroptosis of THP-1 cells via the pro-caspase-1 pathway. Meanwhile, this protein caused the apoptosis of THP-1 cells via the receptor-interacting protein kinase 1/caspase-8/aspase-3 pathway. Tp92 reduced the number of monocytes among peripheral blood mononuclear cells. Interestingly, further research showed that Tp92 failed to increase the tumour necrosis factor-α, interleukin (IL)-1β, IL-6, IL-10, IL-18 and monocyte chemotactic protein 1 (MCP)-1 levels but slightly elevated the IL-8 levels via the Nuclear Factor (NF)-κB pathway in THP-1 cells. The data suggest that Tp92 recognizes CD14 and TLR2, transfers the signal to a downstream pathway, and activates NF-κB to mediate the production of IL-8. This mechanism may help T. pallidum escape recognition and elimination by the host innate immune system.

Topics: Antigens, Surface; Bacterial Proteins; Caspase 1; Cell Death; Cell Line, Tumor; Cytokines; Host-Pathogen Interactions; Humans; Interleukin-8; Leukemia, Monocytic, Acute; Leukocytes, Mononuclear; Lipopolysaccharide Receptors; NF-kappa B; Recombinant Proteins; Signal Transduction; Syphilis; Toll-Like Receptor 2; Treponema pallidum

Sodium azide (NaN

Topics: Adaptor Proteins, Signal Transducing; Animals; Cell Line, Tumor; Chemokine CCL2; Gene Expression Regulation; I-kappa B Proteins; Inflammation Mediators; Interleukin-8; Leukemia, Monocytic, Acute; Lipopolysaccharides; Macrophages; Mice; NF-kappa B; Nuclear Proteins; Phosphorylation; Protein Processing, Post-Translational; RAW 264.7 Cells; Sodium Azide; STAT1 Transcription Factor; Tumor Necrosis Factor-alpha

Capsaicin, a spicy component of hot peppers, has been shown to improve inflammatory disease and obesity. In this study, we tested the hypothesis that the anti-inflammatory activity of capsaicin can be used to improve free fatty acid (FFA)-induced inflammation by reducing gene expression of macrophage inflammatory protein 1 (MIP-1) and interleukin 8 (IL-8) in THP-1 (human acute monocytic leukemia cell) macrophages. To investigate whether capsaicin ameliorates palmitate-induced MIP-1 and IL-8 gene expressions, we treated THP-1 cells with palmitate in the presence or absence of capsaicin and measured MIP-1 and IL-8 by real-time polymerase chain reaction. To elucidate the mechanism by which capsaicin effects on palmitate-induced MIP-1 and IL-8 gene expressions, we performed immunoblotting with stress kinase-related antibodies and measured palmitate oxidation and palmitate oxidation-related gene expression. Palmitate and stearate but not the unsaturated FFA oleate significantly increased MIP-1 and IL-8 expressions in THP-1 macrophages. Treatment with capsaicin or FFA oxidation stimulators inhibited palmitate-induced MIP-1 and IL-8 expressions in THP-1 macrophages. Capsaicin increased the gene expression of carnitine palmitoyltransferase 1 and the β-oxidation of palmitate. Furthermore, capsaicin significantly reduced palmitate-stimulated activation of c-Jun N-terminal kinase, c-Jun, and p38. Our data suggest that the attenuation of palmitate-induced MIP-1 and IL-8 gene expressions by capsaicin is associated with reduced activation of c-Jun N-terminal kinase, c-Jun, and p38 and preserved β-oxidation activity.

Topics: Anti-Inflammatory Agents; Capsaicin; Capsicum; Cell Line, Tumor; Gene Expression Regulation; Humans; Immunoblotting; Interleukin-8; JNK Mitogen-Activated Protein Kinases; Leukemia, Monocytic, Acute; Macrophage Inflammatory Proteins; Oxidation-Reduction; p38 Mitogen-Activated Protein Kinases; Palmitates; Plant Extracts

The elemental diet is one of the effective therapies for inflammatory bowel disease. However, the mechanism remains unclear, and there have never been reports about the inhibitory effects of amino acids in human monocytes/macrophages. We investigated the inhibitory effects of amino acids on cytokine production or expression of adhesion molecules that are involved in inflammatory diseases, in human monocytes/macrophages.. We examined the inhibitory effects of cysteine, histidine or glycine on the induction of nuclear factor-κB (NF-κB) activation, expression of intracellular adhesion molecule-1 (ICAM-1, CD54) and production of interleukin-8 (IL-8) in THP-1 cells, a human monocytic leukemia cell line, and peripheral blood mononuclear cells (PBMCs) stimulated with tumor necrosis factor-α (TNF-α).. Cysteine, histidine and glycine significantly reduced the activation of NF-κB in THP-1 cells stimulated with TNF-α. In addition, cysteine and histidine significantly inhibited the expression of ICAM-1 and production of IL-8 in THP-1 cells and PBMCs.. Our results suggest that cysteine and histidine exhibit anti-inflammatory effects in THP-1 cells, and may be responsible for the efficacy of treatment in inflammatory bowel diseases.

Topics: Amino Acids; Anti-Inflammatory Agents; Cytokines; Dose-Response Relationship, Drug; Humans; Inflammation; Intercellular Adhesion Molecule-1; Interleukin-8; Leukemia, Monocytic, Acute; Leukocytes, Mononuclear; Macrophages; NF-kappa B; Phosphorylation; Polymerase Chain Reaction; Tumor Necrosis Factor-alpha

Topics: Cell Differentiation; Cells, Cultured; Gene Expression Profiling; Granulocyte-Macrophage Colony-Stimulating Factor; Humans; Hyaluronan Receptors; Interleukin-8; Leukemia, Monocytic, Acute

Cigarette smoke-mediated oxidative stress induces an inflammatory response in the lungs by stimulating the release of proinflammatory cytokines. Chromatin remodeling due to histone acetylation and deacetylation is known to play an important role in transcriptional regulation of proinflammatory genes. The aim of this study was to investigate the molecular mechanism(s) of inflammatory responses caused by cigarette smoke extract (CSE) in the human macrophage-like cell line MonoMac6 and whether the treatment of these cells with the antioxidant glutathione (GSH) monoethyl ester, or modulation of the thioredoxin redox system, can attenuate cigarette smoke-mediated IL-8 release. Exposure of MonoMac6 cells to CSE (1% and 2.5%) increased IL-8 and TNF-alpha production vs. control at 24 h and was associated with significant depletion of GSH levels associated with increased reactive oxygen species release in addition to activation of NF-kappaB. Inhibition of IKK ablated the CSE-mediated IL-8 release, suggesting that this process is dependent on the NF-kappaB pathway. CSE also reduced histone deacetylase (HDAC) activity and HDAC1, HDAC2, and HDAC3 protein levels. This was associated with posttranslational modification of HDAC1, HDAC2, and HDAC3 protein by nitrotyrosine and aldehyde-adduct formation. Pretreatment of cells with GSH monoethyl ester, but not thioredoxin/thioredoxin reductase, reversed cigarette smoke-induced reduction in HDAC levels and significantly inhibited IL-8 release. Thus cigarette smoke-induced release of IL-8 is associated with activation of NF-kappaB via IKK and reduction in HDAC levels/activity in macrophages. Moreover, cigarette smoke-mediated proinflammatory events are regulated by the redox status of the cells.

Topics: Cell Line, Tumor; Glutathione; Histone Deacetylases; Humans; I-kappa B Kinase; Interleukin-8; Leukemia, Monocytic, Acute; Macrophages; NF-kappa B; Oxidants; Oxidative Stress; Protein Processing, Post-Translational; Pulmonary Disease, Chronic Obstructive; Signal Transduction; Smoking; Thioredoxin-Disulfide Reductase; Tumor Necrosis Factor-alpha

Erythromycin and other macrolides are effective for the treatment of chronic inflammatory airway diseases such as diffuse panbronchiolitis (DPB) and chronic sinusitis. The effect of macrolides in DPB is suggested to be anti-inflammatory rather than antibacterial. We investigated the effects of clarithromycin on interleukin-8 (IL-8) production using human peripheral monocytes and the human monocytic leukaemia cell line, THP-1. Bacterial extracts from Escherichia coli, Pseudomonas aeruginosa and Helicobacter pylori, as well as E. coli-derived lipopolysaccharide (LPS), induced IL-8 production. Clarithromycin suppressed this production in a dose-dependent manner in both monocytes and THP-1 cells (49.3-75.0% inhibition at 10 mg/L). A luciferase reporter gene assay with plasmids containing a serially deleted IL-8 promoter fragment showed that both the activator protein-1 (AP-1) and/or the nuclear factor-kappa B (NF-kapp aB) binding sequences were responsible for the LPS and clarithromycin responsiveness of the IL-8 promoter. Consistently, in an electromobility shift assay, LPS increased the specific binding of both AP-1 and NF-kappaB, whereas clarithromycin suppressed it. Moreover, LPS and clarithromycin regulated three other promoters that have either the NF-kappa B or the AP-1 binding sequences: two synthetic (pAP-1-Luc and pNF-kappa B-Luc) and one naturally occurring (ELAM-Luc). Our results indicate that clarithromycin modified inflammation by sup-pressing IL-8 production and that clarithromycin may affect the expression of other genes through AP-1 and NF-kappa B. In addition to treatment of airway diseases, the anti-inflammatory effect of macrolides may be beneficial for the treatment of other inflammatory diseases such as chronic gastritis caused by H. pylori.

Topics: Anti-Bacterial Agents; Clarithromycin; Depression, Chemical; Escherichia coli; Humans; Indicators and Reagents; Interleukin-8; Leukemia, Monocytic, Acute; Lipopolysaccharides; Luciferases; Monocytes; NF-kappa B; Nuclear Proteins; Pancreatitis-Associated Proteins; Plasmids; RNA, Messenger; Transcription Factor AP-1; Transfection; Tumor Cells, Cultured

Compound T-614, a member of the methanesulfoanilide class of anti-inflammatory agents, shows potent anti-arthritic activity in animal models of rheumatoid arthritis. The aim of the present investigation was to characterize the anti-arthritic activity of T-614 in terms of regulation of the nuclear transcription factor NF-kappaB, which is associated with expression of many immune and inflammatory genes.. THP-1 cells (human monocytic leukemia cell line) were used throughout this in vitro study, and lipopolysaccharide (LPS) and tumor necrosis factor (TNF)-alpha were employed for activation of the cells. Cytokine production was assayed by enzyme-linked immunosorbent assay (ELISA). The mRNA levels were determined by a semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) assay. Assessment of the NF-kappaB DNA binding activity was performed by an electrophoretic mobility shift assay (EMSA) using a digoxigenin (DIG)-labeled double-stranded oligonucleotide containing kappaB-binding site. Degradation kinetics of the cytosolic NF-kappaB inhibitor a (IkappaBalpha) were studied by Western blot analysis.. T-614 inhibited LPS-stimulated production of TNF-alpha, interleukin (IL)-6, and IL-8 in a concentration-dependent manner with decreasing mRNA levels (IL-6 and IL-8). EMSA study showed that T-614 prevented TNF-alpha as well as LPS-stimulated activation of NF-kappaB, and Western blot analysis proved that T-614 did not affect degradation of IkappaBalpha protein.. These results suggest that the inhibitory effect of T-614 on the production of TNF-alpha, IL-6 and IL-8 in LPS-stimulated THP-1 cells may involve transcriptional regulation through suppression of NF-kappaB activation without interfering with IkappaBalpha degradation.

Topics: Antirheumatic Agents; Benzopyrans; Biotransformation; Blotting, Western; Cell Nucleus; Cytokines; Electrophoresis; Enzyme-Linked Immunosorbent Assay; Humans; I-kappa B Proteins; Interleukin-6; Interleukin-8; Leukemia, Monocytic, Acute; Lipopolysaccharides; NF-kappa B; NF-KappaB Inhibitor alpha; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Sulfonamides; Tumor Cells, Cultured; Tumor Necrosis Factor-alpha

The biochemical pathways involved in CD40 signaling have been extensively studied in B cells and B cell lines, and appear to be primarily initiated by recruitment of the tumor necrosis factor (TNF) receptor-associated factor (TRAF) signaling proteins to the CD40 cytoplasmic domain. Signaling pathways activated through CD40 in monocytes/macrophages have not been characterized as well as in B cells. Using human monocytes and the human monocytic cell line THP1, we examined signal transduction events induced by CD40 engagement with its ligand, CD154. In human monocytes, all TRAF mRNAs were expressed constitutively and CD40 ligation resulted in a strong up-regulation of TRAF1 mRNA. In THP1 cells, CD40 ligation induced expression of TRAF1 and TRAF5 mRNAs. Engagement of CD40 in both monocytes and THP1 cells led to the rapid and transient activation of the extracellular signal-regulated kinases (ERK) 1 and 2, and to low levels of JNK activation. No CD40-dependent activation of p38 mitogen-activated protein kinase (MAPK) was found. In CD154-stimulated monocytes and THP1 cells the upstream ERK1/2 activator, MAPK kinase (MEK) 1/2, and downstream substrate, c-Myc, were activated. By blocking activation of ERK1/2 with a MEK-specific inhibitor, PD98059, CD40-dependent secretion of the pro-inflammatory cytokines, TNF-alpha, IL-6 and IL-8, was demonstrated to be linked to the ERK1/2 pathway. The ERK1/2 pathway did not appear to be involved in up-regulating TRAF1 and TRAF5 mRNAs in THP1 cells. Collectively, these results suggest distinct differences between B cells and monocytic cells in CD40-dependent activation of MAPK pathways.

Topics: B-Lymphocytes; Carrier Proteins; CD40 Antigens; CD40 Ligand; Enzyme Activation; Enzyme Inhibitors; Flavonoids; Humans; Interleukin-6; Interleukin-8; Leukemia, Monocytic, Acute; Macromolecular Substances; MAP Kinase Kinase 1; MAP Kinase Kinase Kinase 1; MAP Kinase Signaling System; Mitogen-Activated Protein Kinase 1; Mitogen-Activated Protein Kinase 3; Mitogen-Activated Protein Kinase 8; Mitogen-Activated Protein Kinase Kinases; Mitogen-Activated Protein Kinases; Monocytes; Neoplasm Proteins; p38 Mitogen-Activated Protein Kinases; Protein Biosynthesis; Protein Serine-Threonine Kinases; Proteins; Proto-Oncogene Proteins c-myc; RNA, Messenger; TNF Receptor-Associated Factor 1; TNF Receptor-Associated Factor 2; TNF Receptor-Associated Factor 3; TNF Receptor-Associated Factor 4; TNF Receptor-Associated Factor 5; TNF Receptor-Associated Factor 6; Tumor Cells, Cultured; Tumor Necrosis Factor Receptor-Associated Peptides and Proteins; Tumor Necrosis Factor-alpha

Integrin-mediated signals play an important but poorly understood role in regulating the growth and behavior of tumor cells. In monocytes and monocytic leukemia cells, integrin-mediated adhesion results in a strong induction of a set of immediate early genes that are characteristic of monocytic differentiation and contain consensus NF-kappa B elements in their 5' regulatory regions. To investigate the role of integrin signaling in control of differentiation in a human monocytic leukemia cell line, THP-1 cells were transiently transfected with an NF-kappa B driven CAT reporter gene. Adhesion to fibronectin or cross-linking of beta1 integrins resulted in an NF-kappa B-dependent induction of CAT activity. To evaluate whether integrin signaling in this system intersects with the Ras signal transduction cascade, THP-1 cells were cotransfected with the NF-kappa B reporter and with plasmids that direct the synthesis of normal or mutant forms of Ras or Raf. We found that Ras or Raf dominant negative mutants did not inhibit integrin-mediated activation of the NF-kappa B-driven reporter. However, cotransfection with activated Ras, or with several other cytoplasmic oncogenes, blocked this process. This suggests that in monocytic leukemia cells, an antagonism exists between the mitogenic signals provided by oncogenes and the signals generated by integrin ligation. This antagonism may play an important role in regulating the balance between proliferation and differentiation in monocytic leukemias.

Topics: Cell Adhesion; Cell Differentiation; Cell Division; Chloramphenicol O-Acetyltransferase; Fibronectins; Gene Expression Regulation, Leukemic; Genes, Immediate-Early; Genes, ras; Genes, Reporter; Humans; Integrins; Interleukin-8; Leukemia, Monocytic, Acute; Monocytes; Neoplasm Proteins; NF-kappa B; Oncogenes; Protein Serine-Threonine Kinases; Proto-Oncogene Proteins; Proto-Oncogene Proteins c-raf; Proto-Oncogene Proteins p21(ras); Signal Transduction; Transfection; Tumor Cells, Cultured

Purified leukemic cells from 30 acute myeloid leukemia (AML) cases at diagnosis were investigated for the presence of interleukin 8 (IL-8) mRNA by Northern blot analysis. IL-8 specific transcripts were detected in uncultured blasts in 14/30 cases, 10/14 from patients with M4-M5 and 4/14 from cases with M0-M3 morphology. The transcript expression was associated with the detection of IL-8 molecule in blast cells by immunostaining performed on cytospin preparations. After 24-hour culture, a strong up-regulation or the appearance in cases negative before culture of IL-8 mRNA was observed in all cases tested, and culture supernatants contained high amounts of IL-8. Our data demonstrate that leukemic cells in AML are equipped with the functional apparatus for IL-8 production. Since IL-8 displays a wide range of biological activities, including the regulation of some membrane molecules relevant to adhesion and migration processes, its production by AML blasts might be of relevance for the pattern of leukemic growth.

Topics: Acute Disease; Cell Division; Gene Expression; Humans; Interleukin-8; Leukemia, Monocytic, Acute; Leukemia, Myeloid; Leukemia, Myeloid, Acute; Leukemia, Myelomonocytic, Acute; Leukemia, Promyelocytic, Acute; RNA, Messenger; Tumor Cells, Cultured