Monocyte chemotactic protein-1 deficiency attenuates and high-fat diet exacerbates bone loss in mice with Lewis lung carcinoma.

Science.gov (United States)

Yan, Lin; Nielsen, Forrest H; Sundaram, Sneha; Cao, Jay

2017-04-04

Bone loss occurs in obesity and cancer-associated complications including wasting. This study determined whether a high-fat diet and a deficiency in monocyte chemotactic protein-1 (MCP-1) altered bone structural defects in male C57BL/6 mice with Lewis lung carcinoma (LLC) metastases in lungs. Compared to non-tumor-bearing mice, LLC reduced bone volume fraction, connectivity density, trabecular number, trabecular thickness and bone mineral density and increased trabecular separation in femurs. Similar changes occurred in vertebrae. The high-fat diet compared to the AIN93G diet exacerbated LLC-induced detrimental structural changes; the exacerbation was greater in femurs than in vertebrae. Mice deficient in MCP-1 compared to wild-type mice exhibited increases in bone volume fraction, connectivity density, trabecular number and decreases in trabecular separation in both femurs and vertebrae, and increases in trabecular thickness and bone mineral density and a decrease in structure model index in vertebrae. Lewis lung carcinoma significantly decreased osteocalcin but increased tartrate-resistant acid phosphatase 5b (TRAP 5b) in plasma. In LLC-bearing mice, the high-fat diet increased and MCP-1 deficiency decreased plasma TRAP 5b; neither the high-fat diet nor MCP-1 deficiency resulted in significant changes in plasma concentration of osteocalcin. In conclusion, pulmonary metastasis of LLC is accompanied by detrimental bone structural changes; MCP-1 deficiency attenuates and high-fat diet exacerbates the metastasis-associated bone wasting.

Suppression of blood monocyte and neutrophil chemotaxis in acute human malaria

DEFF Research Database (Denmark)

Nielsen, H; Kharazmi, A; Theander, T G

1986-01-01

tested monocyte chemotactic responsiveness in 19 patients with acute primary attack malaria. In addition, the neutrophil chemotaxis was measured in 12 patients. Before the initiation of antimalarial treatment a significant depression of monocyte chemotaxis was observed in approximately half...... of the patients when compared with healthy control subjects. The depression was found in Plasmodium falciparum malaria as well as in P. vivax or P. ovale malaria patients. The defective responsiveness was not receptor specific, since the responses towards casein and zymosan activated serum proved to be equally...... of treatment, and nearly normalized after 7 days (87% of controls). Furthermore, monocyte phagocytic and candidacidal activities were assessed in the same patients on admission and during the follow-up. In contrast to chemotaxis, these functions were normal in all of the patients whenever measured...

Modulation of neutrophil and monocyte function by recombinant human granulocyte macrophage colony-stimulating factor in patients with lymphoma

DEFF Research Database (Denmark)

Kharazmi, A; Nielsen, H; Hovgaard, D

1991-01-01

by up to 43-fold. rhGM-CSF treatment did not affect degranulation of the neutrophils as measured by release of vitamin B12 binding protein. Degree of modulation of neutrophil and monocyte function by rhGM-CSF was independent of rhGM-CSF dosages administered. These data suggest that phagocytic defence...... and chemiluminescence responses to f-Met-Leu-Phe, zymosan activated serum (ZAS) and opsonized zymosan (OZ) were determined. It was observed that chemotactic response of neutrophils to f-Met-Leu-Phe and ZAS was reduced, whereas the chemiluminescence response of both cell types to f-Met-Leu-Phe and zymosan was enhanced...

Stimulated monocyte IL-6 secretion predicts survival of patients with head and neck squamous cell carcinoma

International Nuclear Information System (INIS)

Heimdal, John-Helge; Kross, Kenneth; Klementsen, Beate; Olofsson, Jan; Aarstad, Hans Jørgen

2008-01-01

This study was performed in order to determine whether monocyte in vitro function is associated with presence, stage and prognosis of head and neck squamous cell carcinoma (HNSCC) disease. Prospective study describing outcome, after at least five years observation, of patients treated for HNSCC disease in relation to their monocyte function. Sixty-five patients with newly diagnosed HNSCC and eighteen control patients were studied. Monocyte responsiveness was assessed by measuring levels of monocyte in vitro interleukin (IL)-6 and monocyte chemotactic peptide (MCP)-1 secretion after 24 hours of endotoxin stimulation in cultures supplied either with 20% autologous serum (AS) or serum free medium (SFM). Survival, and if relevant, cause of death, was determined at least 5 years following primary diagnosis. All patients, as a group, had higher in vitro monocyte responsiveness in terms of IL-6 (AS) (t = 2.03; p < 0.05) and MCP-1 (SFM) (t = 2.49; p < 0.05) compared to controls. Increased in vitro monocyte IL-6 endotoxin responsiveness under the SFM condition was associated with decreased survival rate (Hazard ratio (HR) = 2.27; Confidence interval (CI) = 1.05–4.88; p < 0.05). The predictive value of monocyte responsiveness, as measured by IL-6, was also retained when adjusted for age, gender and disease stage of patients (HR = 2.67; CI = 1.03–6.92; p < 0.05). With respect to MCP-1, low endotoxin-stimulated responsiveness (AS), analysed by Kaplan-Meier method, predicted decreased survival (χ = 4.0; p < 0.05). In HNSCC patients, changed monocyte in vitro response to endotoxin, as measured by increased IL-6 (SFM) and decreased MCP-1 (AS) responsiveness, are negative prognostic factors

Polarization of migrating monocytic cells is independent of PI 3-kinase activity.

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Silvia Volpe

Full Text Available BACKGROUND: Migration of mammalian cells is a complex cell type and environment specific process. Migrating hematopoietic cells assume a rapid amoeboid like movement when exposed to gradients of chemoattractants. The underlying signaling mechanisms remain controversial with respect to localization and distribution of chemotactic receptors within the plasma membrane and the role of PI 3-kinase activity in cell polarization. METHODOLOGY/PRINCIPAL FINDINGS: We present a novel model for the investigation of human leukocyte migration. Monocytic THP-1 cells transfected with the alpha(2A-adrenoceptor (alpha(2AAR display comparable signal transduction responses, such as calcium mobilization, MAP-kinase activation and chemotaxis, to the noradrenaline homologue UK 14'304 as when stimulated with CCL2, which binds to the endogenous chemokine receptor CCR2. Time-lapse video microscopy reveals that chemotactic receptors remain evenly distributed over the plasma membrane and that their internalization is not required for migration. Measurements of intramolecular fluorescence resonance energy transfer (FRET of alpha(2AAR-YFP/CFP suggest a uniform activation of the receptors over the entire plasma membrane. Nevertheless, PI 3-kinase activation is confined to the leading edge. When reverting the gradient of chemoattractant by moving the dispensing micropipette, polarized monocytes--in contrast to neutrophils--rapidly flip their polarization axis by developing a new leading edge at the previous posterior side. Flipping of the polarization axis is accompanied by re-localization of PI-3-kinase activity to the new leading edge. However, reversal of the polarization axis occurs in the absence of PI 3-kinase activation. CONCLUSIONS/SIGNIFICANCE: Accumulation and internalization of chemotactic receptors at the leading edge is dispensable for cell migration. Furthermore, uniformly distributed receptors allow the cells to rapidly reorient and adapt to changes in the

Leishmania major surface protease Gp63 interferes with the function of human monocytes and neutrophils in vitro

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Sørensen, A L; Hey, A S; Kharazmi, A

1994-01-01

In the present study the effect of Leishmania major surface protease Gp63 on the chemotaxis and oxidative burst response of human peripheral blood monocytes and neutrophils was investigated. It was shown that prior incubation of cells with Gp63 inhibited chemotaxis of neutrophils but not monocytes...... towards the chemotactic peptide f-met-leu-phe. On the other hand, chemotaxis of both neutrophils and monocytes towards zymosan-activated serum containing C5a was inhibited by Gp63. Monocyte and neutrophil chemiluminescence response to opsonized zymosan was reduced by preincubation of the cells with Gp63...... in a concentration-dependent manner. Notably, monocytes were inhibited to a much greater degree than neutrophils by a given concentration of Gp63, and they were also inhibited at much lower concentrations of the protease. The inhibitory effect of Gp63 on chemotaxis and chemiluminescence was completely abolished...

The chemotactic activity of sputum from patients with bronchiectasis.

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Mikami, M; Llewellyn-Jones, C G; Bayley, D; Hill, S L; Stockley, R A

1998-03-01

Persistent polymorphonuclear neutrophil (PMN) recruitment to airway is thought to be an important component of continuing inflammation and progression of chronic destructive lung diseases. Although chemoattractants are required for the PMN to migrate, the nature of the chemoattractants in the airways has not yet been clarified. We therefore investigated the contribution of interleukin-8 (IL-8) and leukotriene-B4 (LTB4) to the chemotactic activity of lung secretions by inhibiting their activity using a monoclonal antibody to IL-8 and an LTB4 receptor antagonist (LY293111 sodium). Fifty-nine sputum samples obtained from 19 patients with bronchiectasis were studied. In preliminary studies the chemotactic responses to IL-8 and LTB4 were found to be additive, and we were able to remove their contribution independently with the appropriate antibody and antagonist. The chemotactic activity of the secretions was related to the macroscopic appearance (mucoid, mucopurulent, and purulent), and this appeared to be related to an increase in IL-8 contribution. Chemotactic activity was reduced by antibiotic therapy and again that seemed to relate to a reduction in the IL-8 contribution. The contributions of LTB4 were similar among the three types of sputum in varying clinical states. These data suggest that LTB4 and IL-8 are important chemotactic factors in lung secretions from such patients, although IL-8 appears to play a more important role during acute exacerbations. These results may be useful in determining therapeutic strategies for chronic destructive lung diseases in the future.

Ureaplasma isolates stimulate pro-inflammatory CC chemokines and matrix metalloproteinase-9 in neonatal and adult monocytes

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Silwedel, Christine; Fehrholz, Markus; Henrich, Birgit; Waaga-Gasser, Ana Maria; Claus, Heike; Speer, Christian P.

2018-01-01

Being generally regarded as commensal bacteria, the pro-inflammatory capacity of Ureaplasma species has long been debated. Recently, we confirmed Ureaplasma–driven pro-inflammatory cytokine responses and a disturbance of cytokine equilibrium in primary human monocytes in vitro. The present study addressed the expression of CC chemokines and matrix metalloproteinase-9 (MMP-9) in purified term neonatal and adult monocytes stimulated with serovar 8 of Ureaplasma urealyticum (Uu) and serovar 3 of U. parvum (Up). Using qRT-PCR and multi-analyte immunoassay, we assessed mRNA and protein expression of the monocyte chemotactic proteins 1 and 3 (MCP-1/3), the macrophage inflammatory proteins 1α and 1β (MIP-1α/β) as well as MMP-9. For the most part, both isolates stimulated mRNA expression of all given chemokines and MMP-9 in cord blood and adult monocytes (pUreaplasma isolates in vitro, adding to our previous data. Findings from co-stimulated cells indicate that Ureaplasma may modulate monocyte immune responses to a second stimulus. PMID:29558521

Microparticles engineered to highly express peroxisome proliferator-activated receptor-γ decreased inflammatory mediator production and increased adhesion of recipient monocytes.

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Sahler, Julie; Woeller, Collynn F; Phipps, Richard P

2014-01-01

Circulating blood microparticles are submicron vesicles released primarily by megakaryocytes and platelets that act as transcellular communicators. Inflammatory conditions exhibit elevated blood microparticle numbers compared to healthy conditions. Direct functional consequences of microparticle composition, especially internal composition, on recipient cells are poorly understood. Our objective was to evaluate if microparticle composition could impact the function of recipient cells, particularly during inflammatory provocation. We therefore engineered the composition of megakaryocyte culture-derived microparticles to generate distinct microparticle populations that were given to human monocytes to assay for influences recipient cell function. Herein, we tested the responses of monocytes exposed to either control microparticles or microparticles that contain the anti-inflammatory transcription factor, peroxisome proliferator-activated receptor-γ (PPARγ). In order to normalize relative microparticle abundance from two microparticle populations, we implemented a novel approach that utilizes a Nanodrop Spectrophotometer to assay for microparticle density rather than concentration. We found that when given to peripheral blood mononuclear cells, microparticles were preferentially internalized by CD11b+ cells, and furthermore, microparticle composition had a profound functional impact on recipient monocytes. Specifically, microparticles containing PPARγ reduced activated monocyte production of the proinflammatory cytokines interleukin-8 and monocyte chemotactic protein-1 compared to activated monocytes exposed to control microparticles. Additionally, treatment with PPARγ microparticles greatly increased monocyte cell adherence. This change in morphology occurred simultaneously with increased production of the key extracellular matrix protein, fibronectin and increased expression of the fibronectin-binding integrin, ITGA5. PPARγ microparticles also changed monocyte

Lipopolysaccharide regulated protein expression is only partly impaired in monocytes from patients with type I diabetes

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Abke Sabine

2006-03-01

Full Text Available Abstract Background Monocytes play an important role in innate immunity and atherosclerosis. A disturbed secretion of cytokines in lipopolysaccharide (LPS activated monocytes from type 1 diabetes (T1D patients has been described and may contribute to the impaired inflammatory response in these individuals. In the present study the influence of LPS on five different proteins with a function in immunity and atherosclerosis was analyzed in monocytes from controls and T1D patients. Methods Monocytes were isolated from controls and T1D patients and the LPS-stimulated increase of IL-6, CXCL8, monocyte chemotactic protein 1 (CCL2, MCP-1 and superoxide dismutase (SOD 2, as well as the LPS-mediated decrease of apolipoprotein E (Apo E in primary human monocytes from controls and T1D patients was determined. Results CCL2 and IL-6 secretion in response to LPS was found significantly reduced in monocytes from T1D patients when compared to controls whereas basal CCL2 release was similar in control and T1D cells. In contrast, CXCL8 and apolipoprotein E secretion and SOD 2 expression upon LPS stimulation is similar from T1D and control monocytes. Conclusion These data indicate that LPS-mediated protein expression is only partly disturbed in monocytes from T1D patients. Reduced secretion of IL-6 and CCL2 in activated monocytes of these patients may contribute to an impaired inflammatory response and vascular disease.

Macrophage colony-stimulating factor augments Tie2-expressing monocyte differentiation, angiogenic function, and recruitment in a mouse model of breast cancer.

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Forget, Mary A; Voorhees, Jeffrey L; Cole, Sara L; Dakhlallah, Duaa; Patterson, Ivory L; Gross, Amy C; Moldovan, Leni; Mo, Xiaokui; Evans, Randall; Marsh, Clay B; Eubank, Tim D

2014-01-01

Reports demonstrate the role of M-CSF (CSF1) in tumor progression in mouse models as well as the prognostic value of macrophage numbers in breast cancer patients. Recently, a subset of CD14+ monocytes expressing the Tie2 receptor, once thought to be predominantly expressed on endothelial cells, has been characterized. We hypothesized that increased levels of CSF1 in breast tumors can regulate differentiation of Tie2- monocytes to a Tie2+ phenotype. We treated CD14+ human monocytes with CSF1 and found a significant increase in CD14+/Tie2+ positivity. To understand if CSF1-induced Tie2 expression on these cells improved their migratory ability, we pre-treated CD14+ monocytes with CSF1 and used Boyden chemotaxis chambers to observe enhanced response to angiopoietin-2 (ANG2), the chemotactic ligand for the Tie2 receptor. We found that CSF1 pre-treatment significantly augmented chemotaxis and that Tie2 receptor upregulation was responsible as siRNA targeting Tie2 receptor abrogated this effect. To understand any augmented angiogenic effect produced by treating these cells with CSF1, we cultured human umbilical vein endothelial cells (HUVECs) with conditioned supernatants from CSF1-pre-treated CD14+ monocytes for a tube formation assay. While supernatants from CSF1-pre-treated TEMs increased HUVEC branching, a neutralizing antibody against the CSF1R abrogated this activity, as did siRNA against the Tie2 receptor. To test our hypothesis in vivo, we treated PyMT tumor-bearing mice with CSF1 and observed an expansion in the TEM population relative to total F4/80+ cells, which resulted in increased angiogenesis. Investigation into the mechanism of Tie2 receptor upregulation on CD14+ monocytes by CSF1 revealed a synergistic contribution from the PI3 kinase and HIF pathways as the PI3 kinase inhibitor LY294002, as well as HIF-1α-deficient macrophages differentiated from the bone marrow of HIF-1αfl/fl/LysMcre mice, diminished CSF1-stimulated Tie2 receptor expression.

Platelet-derived stromal cell-derived factor-1 is required for the transformation of circulating monocytes into multipotential cells.

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Noriyuki Seta

Full Text Available BACKGROUND: We previously described a primitive cell population derived from human circulating CD14(+ monocytes, named monocyte-derived multipotential cells (MOMCs, which are capable of differentiating into mesenchymal and endothelial lineages. To generate MOMCs in vitro, monocytes are required to bind to fibronectin and be exposed to soluble factor(s derived from circulating CD14(- cells. The present study was conducted to identify factors that induce MOMC differentiation. METHODS: We cultured CD14(+ monocytes on fibronectin in the presence or absence of platelets, CD14(- peripheral blood mononuclear cells, platelet-conditioned medium, or candidate MOMC differentiation factors. The transformation of monocytes into MOMCs was assessed by the presence of spindle-shaped adherent cells, CD34 expression, and the potential to differentiate in vitro into mesenchymal and endothelial lineages. RESULTS: The presence of platelets or platelet-conditioned medium was required to generate MOMCs from monocytes. A screening of candidate platelet-derived soluble factors identified stromal cell-derived factor (SDF-1 as a requirement for generating MOMCs. Blocking an interaction between SDF-1 and its receptor CXCR4 inhibited MOMC generation, further confirming SDF-1's critical role in this process. Finally, circulating MOMC precursors were found to reside in the CD14(+CXCR4(high cell population. CONCLUSION: The interaction of SDF-1 with CXCR4 is essential for the transformation of circulating monocytes into MOMCs.

Microparticles engineered to highly express peroxisome proliferator-activated receptor-γ decreased inflammatory mediator production and increased adhesion of recipient monocytes.

Directory of Open Access Journals (Sweden)

Julie Sahler

Full Text Available Circulating blood microparticles are submicron vesicles released primarily by megakaryocytes and platelets that act as transcellular communicators. Inflammatory conditions exhibit elevated blood microparticle numbers compared to healthy conditions. Direct functional consequences of microparticle composition, especially internal composition, on recipient cells are poorly understood. Our objective was to evaluate if microparticle composition could impact the function of recipient cells, particularly during inflammatory provocation. We therefore engineered the composition of megakaryocyte culture-derived microparticles to generate distinct microparticle populations that were given to human monocytes to assay for influences recipient cell function. Herein, we tested the responses of monocytes exposed to either control microparticles or microparticles that contain the anti-inflammatory transcription factor, peroxisome proliferator-activated receptor-γ (PPARγ. In order to normalize relative microparticle abundance from two microparticle populations, we implemented a novel approach that utilizes a Nanodrop Spectrophotometer to assay for microparticle density rather than concentration. We found that when given to peripheral blood mononuclear cells, microparticles were preferentially internalized by CD11b+ cells, and furthermore, microparticle composition had a profound functional impact on recipient monocytes. Specifically, microparticles containing PPARγ reduced activated monocyte production of the proinflammatory cytokines interleukin-8 and monocyte chemotactic protein-1 compared to activated monocytes exposed to control microparticles. Additionally, treatment with PPARγ microparticles greatly increased monocyte cell adherence. This change in morphology occurred simultaneously with increased production of the key extracellular matrix protein, fibronectin and increased expression of the fibronectin-binding integrin, ITGA5. PPARγ microparticles

Macrophage colony-stimulating factor augments Tie2-expressing monocyte differentiation, angiogenic function, and recruitment in a mouse model of breast cancer.

Directory of Open Access Journals (Sweden)

Mary A Forget

Full Text Available Reports demonstrate the role of M-CSF (CSF1 in tumor progression in mouse models as well as the prognostic value of macrophage numbers in breast cancer patients. Recently, a subset of CD14+ monocytes expressing the Tie2 receptor, once thought to be predominantly expressed on endothelial cells, has been characterized. We hypothesized that increased levels of CSF1 in breast tumors can regulate differentiation of Tie2- monocytes to a Tie2+ phenotype. We treated CD14+ human monocytes with CSF1 and found a significant increase in CD14+/Tie2+ positivity. To understand if CSF1-induced Tie2 expression on these cells improved their migratory ability, we pre-treated CD14+ monocytes with CSF1 and used Boyden chemotaxis chambers to observe enhanced response to angiopoietin-2 (ANG2, the chemotactic ligand for the Tie2 receptor. We found that CSF1 pre-treatment significantly augmented chemotaxis and that Tie2 receptor upregulation was responsible as siRNA targeting Tie2 receptor abrogated this effect. To understand any augmented angiogenic effect produced by treating these cells with CSF1, we cultured human umbilical vein endothelial cells (HUVECs with conditioned supernatants from CSF1-pre-treated CD14+ monocytes for a tube formation assay. While supernatants from CSF1-pre-treated TEMs increased HUVEC branching, a neutralizing antibody against the CSF1R abrogated this activity, as did siRNA against the Tie2 receptor. To test our hypothesis in vivo, we treated PyMT tumor-bearing mice with CSF1 and observed an expansion in the TEM population relative to total F4/80+ cells, which resulted in increased angiogenesis. Investigation into the mechanism of Tie2 receptor upregulation on CD14+ monocytes by CSF1 revealed a synergistic contribution from the PI3 kinase and HIF pathways as the PI3 kinase inhibitor LY294002, as well as HIF-1α-deficient macrophages differentiated from the bone marrow of HIF-1αfl/fl/LysMcre mice, diminished CSF1-stimulated Tie2 receptor

Characterization of recombinant human HBP/CAP37/azurocidin, a pleiotropic mediator of inflammation-enhancing LPS-induced cytokine release from monocytes.

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Rasmussen, P B; Bjørn, S; Hastrup, S; Nielsen, P F; Norris, K; Thim, L; Wiberg, F C; Flodgaard, H

1996-07-15

Neutrophil-derived heparin-binding protein (HBP) is a strong chemoattractant for monocytes. We report here for the first time the expression of recombinant HBP. A baculovirus containing the human HBP cDNA mediated in insect cells the secretion of a 7-residue N-terminally extended HBP form (pro-HBP). Deletion of the pro-peptide-encoding cDNA sequence resulted in correctly processed HBP at the N-terminus. Electrospray mass spectrum analysis of recombinant HBP yielded a molecular weight of 27.237 +/- 3 amu. Consistent with this mass is a HBP form of 225 amino acids (mature part +3 amino acid C-terminal extension). The biological activity of recombinant HBP was confirmed by its chemotactic action towards monocytes. Furthermore, we have shown that recombinant HBP stimulates in a dose-dependent manner the lipopolysaccharide (LPS)-induced cytokine release from human monocytes.

Macrophage mitochondrial oxidative stress promotes atherosclerosis and nuclear factor-κB-mediated inflammation in macrophages.

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Wang, Ying; Wang, Gary Z; Rabinovitch, Peter S; Tabas, Ira

2014-01-31

Mitochondrial oxidative stress (mitoOS) has been shown to correlate with the progression of human atherosclerosis. However, definitive cell type-specific causation studies in vivo are lacking, and the molecular mechanisms of potential proatherogenic effects remain to be determined. Our aims were to assess the importance of macrophage mitoOS in atherogenesis and to explore the underlying molecular mechanisms. We first validated Western diet-fed Ldlr(-/-) mice as a model of human mitoOS-atherosclerosis association by showing that non-nuclear oxidative DNA damage, a marker of mitoOS in lesional macrophages, correlates with aortic root lesion development. To investigate the importance of macrophage mitoOS, we used a genetic engineering strategy in which the OS suppressor catalase was ectopically expressed in mitochondria (mCAT) in macrophages. MitoOS in lesional macrophages was successfully suppressed in these mice, and this led to a significant reduction in aortic root lesional area. The mCAT lesions had less monocyte-derived cells, less Ly6c(hi) monocyte infiltration into lesions, and lower levels of monocyte chemotactic protein-1. The decrease in lesional monocyte chemotactic protein-1 was associated with the suppression of other markers of inflammation and with decreased phosphorylation of RelA (NF-κB p65), indicating decreased activation of the proinflammatory NF-κB pathway. Using models of mitoOS in cultured macrophages, we showed that mCAT suppressed monocyte chemotactic protein-1 expression by decreasing the activation of the IκB-kinase β-RelA NF-κB pathway. MitoOS in lesional macrophages amplifies atherosclerotic lesion development by promoting NF-κB-mediated entry of monocytes and other inflammatory processes. In view of the mitoOS-atherosclerosis link in human atheromata, these findings reveal a potentially new therapeutic target to prevent the progression of atherosclerosis.

Glatiramer acetate (GA) prevents TNF-α-induced monocyte adhesion to primary endothelial cells through interfering with the NF-κB pathway

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Wei, Guoqian; Zhang, Xueyan; Su, Zhendong; Li, Xueqi, E-mail: xueqili075@yeah.net

2015-01-30

Highlights: • GA inhibited TNF-α-induced binding of monocytes to endothelial cells. • GA inhibited the induction of adhesion molecules MCP-1, VCAM-1 and E-selectin. • GA inhibits NF-κB p65 nuclear translocation and transcriptional activity. • GA inhibits TNF-α-induced IκBα degradation. - Abstract: Pro-inflammatory cytokines such as tumor necrosis factor-alpha (TNF-α) is considered to be the major one contributing to the process of development of endothelial dysfunction. Exposure to TNF-α induces the expression of a number of proinflammatory chemokines, such as monocyte chemotactic protein-1 (MCP-1), and adhesion molecules, including vascular adhesion molecule-1 (VCAM-1) and E-selectin, which mediate the interaction of invading monocytes with vascular endothelial cells. Glatiramer acetate (GA) is a licensed clinical drug for treating patients suffering from multiple sclerosis (MS). The effects of GA in vascular disease have not shown before. In this study, we found that GA significantly inhibited TNF-α-induced binding of monocytes to endothelial cells. Mechanistically, we found that GA ameliorated the upregulation of MCP-1, VCAM-1, and E-selectin induced by TNF-α. Notably, this process is mediated by inhibiting the nuclear translocation and activation of NF-κB. Our results also indicate that GA pretreatment attenuates the up-regulation of COX-2 and iNOS. These data suggest that GA might have a potential benefit in therapeutic endothelial dysfunction related diseases.

Characterization of two types of osteoclasts from human peripheral blood monocytes

International Nuclear Information System (INIS)

Yuasa, Kimitaka; Mori, Kouki; Ishikawa, Hitoshi; Sudo, Akihiro; Uchida, Atsumasa; Ito, Yasuhiko

2007-01-01

The two osteoclastogenesis pathways, receptor activator nuclear factor (NF)-κB ligand (RANKL)-mediated and fusion regulatory protein-1 (FRP-1)-mediated osteoclastogenesis, have recently been reported. There were significant differences in differentiation and activation mechanisms between the two pathways. When monocytes were cultured with FRP-1 without adding M-CSF, essential for the RANKL system, TRAP-positive polykaryocyte formation occurred. FRP-1-mediated osteoclasts formed larger pits on mineralized calcium phosphate plates than RANKL+M-CSF-mediated osteoclasts did. Lacunae on dentin surfaces induced by FRP-1-mediated osteoclasts were inclined to be single and isolated. However, osteoclasts induced by RANKL+M-CSF made many connected pits on dentin surfaces as if they crawled on there. Interestingly, FRP-1 osteoclastogenesis was enhanced by M-CSF/IL-1α, while chemotactic behavior to the dentin slices was not effected. There were differences in pH and concentration of HCO3- at culture endpoint and in adherent feature to dentin surfaces. Our findings indicate there are two types of osteoclasts with distinct properties

Effects of peritoneal fluid from endometriosis patients on the release of monocyte-specific chemokines by leukocytes.

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Na, Yong-Jin; Lee, Dong-Hyung; Kim, Seung-Chul; Joo, Jong-Kil; Wang, Ji-Won; Jin, Jun-O; Kwak, Jong-Young; Lee, Kyu-Sup

2011-06-01

Chemokines have been implicated in the pathological process of endometriosis. We compared the effects of peritoneal fluid obtained from patients with endometriosis (ePF) and controls without endometriosis (cPF) on the release of monocyte-specific CC chemokines such as monocyte chemotactic protein-1 (MCP-1), regulated upon activation normal T cell expressed and secreted (RANTES), and macrophage inflammatory protein-1α (MIP-1α) by neutrophils, monocytes, and T cells. Moreover, we evaluated the correlation between the levels of chemokines in ePF and their release by these cells. Cells were obtained from healthy young volunteers and cultured with ePF (n = 12) or cPF (n = 8). The chemokine levels in the ePF and the supernatants of cultured cells with ePF were then measured by ELISA. There was a positive correlation between the levels of MCP-1 and MIP-1α in ePF. The addition of ePF to the cell cultures failed to increase the release of MCP-1, RANTES, and MIP-1α when compared to cPF, but the levels of RANTES in ePF were positively correlated with the release of RANTES by ePF-treated monocytes and T cells. Moreover, there was a positive correlation between the levels of RANTES and MIP-1α released by neutrophils and between the levels of MCP-1 and MIP-1α released by T cells. Finally, the levels of RANTES released by monocyte-derived macrophages and monocytes cultured with ePF were positively correlated. These findings suggest that monocytes, neutrophils, and T cells release differential levels of MCP-1, RANTES, and MIP-1α in response to stimulation with ePF.

Evidence for a novel chemotactic C1q domain-containing factor in the leech nerve cord.

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Tahtouh, Muriel; Croq, Françoise; Vizioli, Jacopo; Sautiere, Pierre-Eric; Van Camp, Christelle; Salzet, Michel; Daha, Mohamed R; Pestel, Joël; Lefebvre, Christophe

2009-02-01

In vertebrates, central nervous system (CNS) protection is dependent on many immune cells including microglial cells. Indeed, activated microglial cells are involved in neuroinflammation mechanisms by interacting with numerous immune factors. Unlike vertebrates, some lophotrochozoan invertebrates can fully repair their CNS following injury. In the medicinal leech Hirudo medicinalis, the recruitment of microglial cells at the lesion site is essential for sprouting of injured axons. Interestingly, a new molecule homologous to vertebrate C1q was characterized in leech, named HmC1q (for H. medicinalis) and detected in neurons and glial cells. In chemotaxis assays, leech microglial cells were demonstrated to respond to human C1q. The chemotactic activity was reduced when microglia was preincubated with signaling pathway inhibitors (Pertussis Toxin or wortmannin) or anti-human gC1qR antibody suggesting the involvement of gC1qR in C1q-mediated migration in leech. Assays using cells preincubated with NO chelator (cPTIO) showed that C1q-mediated migration was associated to NO production. Of interest, by using anti-HmC1q antibodies, HmC1q released in the culture medium was shown to exhibit a similar chemotactic effect on microglial cells as human C1q. In summary, we have identified, for the first time, a molecule homologous to mammalian C1q in leech CNS. Its chemoattractant activity on microglia highlights a new investigation field leading to better understand leech CNS repair mechanisms.

Extracellular Histones Increase Tissue Factor Activity and Enhance Thrombin Generation by Human Blood Monocytes.

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Gould, Travis J; Lysov, Zakhar; Swystun, Laura L; Dwivedi, Dhruva J; Zarychanski, Ryan; Fox-Robichaud, Alison E; Liaw, Patricia C

2016-12-01

Sepsis is characterized by systemic activation of inflammatory and coagulation pathways in response to infection. Recently, it was demonstrated that histones released into the circulation by dying/activated cells may contribute to sepsis pathology. Although the ability of extracellular histones to modulate the procoagulant activities of several cell types has been investigated, the influence of histones on the hemostatic functions of circulating monocytes is unknown. To address this, we investigated the ability of histones to modulate the procoagulant potential of THP-1 cells and peripheral blood monocytes, and examined the effects of plasmas obtained from septic patients to induce a procoagulant phenotype on monocytic cells. Tissue factor (TF) activity assays were performed on histone-treated THP-1 cells and blood monocytes. Exposure of monocytic cells to histones resulted in increases in TF activity, TF antigen, and phosphatidylserine exposure. Histones modulate the procoagulant activity via engagement of Toll-like receptors 2 and 4, and this effect was abrogated with inhibitory antibodies. Increased TF activity of histone-treated cells corresponded to enhanced thrombin generation in plasma determined by calibrated automated thrombography. Finally, TF activity was increased on monocytes exposed to plasma from septic patients, an effect that was attenuated in plasma from patients receiving unfractionated heparin (UFH). Our studies suggest that increased levels of extracellular histones found in sepsis contribute to dysregulated coagulation by increasing TF activity of monocytes. These procoagulant effects can be partially ameliorated in sepsis patients receiving UFH, thereby identifying extracellular histones as a potential therapeutic target for sepsis treatment.

Clinical value of detection on ser um monocyte chemotactant protein-1 and vascular endothelial cadher in levels in patients with acute cerebral infarction

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Xia Zhou

2016-11-01

Full Text Available Objective: To study the correlation of serum monocyte chemotactant protein-1 (MCP-1 and vascular endothelia cadherin (VE-cadherin levels in patients with acute cerebral infarction, and nerve injury molecules, interleukins and matrix metalloproteinases. Methods: A total of 86 patients with acute cerebral infarction treated in our hospital from April 2012 to October 2015 were selected as the observation group and 50 healthy subjects in the same period treated in our hospital were selected as the control group. The serums were collected and the contents of MCP-1, VE-cadherin, heart-type fatty acid binding protein (H-FABP, S100 calcium binding protein B (S100B, neuron-specific enolase (NSE, interleukin-lb (IL-1b, IL-6, IL-17, IL-18, matrix metalloproteinase-2 (MMP2, MMP3 and MMP9 were measured. Results: The serum contents of MCP-1, VE-cadherin, H-FABP, S100B, NSE, IL-1b, IL- 6, IL-17, IL-18, MMP2, MMP3 and MMP9 in observation group were significantly higher than those of control group. Carotid artery plaque formation and unstable plaque properties will increase the serum contents of MCP-1, VE-cadherin, H-FABP, S100B, NSE, IL-1b, IL-6, IL-17, IL-18, MMP2, MMP3 and MMP9 in patients with cerebral infarction. The serum levels of MCP-1, VE-cadherin and the contents of H-FABP, S100B, NSE, IL-1b, IL-6, IL-17, IL-18, MMP2, MMP3 and MMP9 were positively correlated. Conclusions: The serum levels of VE-cadherin and MCP-1 were significantly increased in patients with acute cerebral infarction. MCP-1 and VE-cadherin can increase the secretion of interleukins and matrix metalloproteinases, which can result in the carotid artery plaque formation, unstable plaque properties and the injury of nerve function.

Dyslipidemic Diet-Induced Monocyte “Priming” and Dysfunction in Non-Human Primates Is Triggered by Elevated Plasma Cholesterol and Accompanied by Altered Histone Acetylation

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John D. Short

2017-08-01

Full Text Available Monocytes and the recruitment of monocyte-derived macrophages into sites of inflammation play a key role in atherogenesis and other chronic inflammatory diseases linked to cardiometabolic syndrome and obesity. Previous studies from our group have shown that metabolic stress promotes monocyte priming, i.e., enhanced adhesion and accelerated chemotaxis of monocytes in response to chemokines, both in vitro and in dyslipidemic LDLR−/− mice. We also showed that metabolic stress-induced monocyte dysfunction is, at least to a large extent caused by the S-glutathionylation, inactivation, and subsequent degradation of mitogen-activated protein kinase phosphatase 1. Here, we analyzed the effects of a Western-style, dyslipidemic diet (DD, which was composed of high levels of saturated fat, cholesterol, and simple sugars, on monocyte (dysfunction in non-human primates (NHPs. We found that similar to mice, a DD enhances monocyte chemotaxis in NHP within 4 weeks, occurring concordantly with the onset of hypercholesterolemia but prior to changes in triglycerides, blood glucose, monocytosis, or changes in monocyte subset composition. In addition, we identified transitory decreases in the acetylation of histone H3 at the lysine residues 18 and 23 in metabolically primed monocytes, and we found that monocyte priming was correlated with the acetylation of histone H3 at lysine 27 after an 8-week DD regimen. Our data show that metabolic stress promotes monocyte priming and hyper-chemotactic responses in NHP. The histone modifications accompanying monocyte priming in primates suggest a reprogramming of the epigenetic landscape, which may lead to dysregulated responses and functionalities in macrophages derived from primed monocytes that are recruited to sites of inflammation.

Human Monocytes Accelerate Proliferation and Blunt Differentiation of Preadipocytes in Association With Suppression of C/Ebpα mRNA

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Couturier, Jacob; Patel, Sanjeet G.; Iyer, Dinakar; Balasubramanyam, Ashok; Lewis, Dorothy E.

2015-01-01

Obesity, type 2 diabetes, and HIV-associated lipodystrophy are associated with abnormalities in adipocyte growth and differentiation. In persons with these conditions, adipose depots contain increased numbers of macrophages, but the origins of these cells and their specific effects are uncertain. Peripheral blood mononuclear cells (PBMC)-derived monocytes, but not T cells, cocultured via transwells with primary subcutaneous preadipocytes, increased proliferation (approximately twofold) and reduced differentiation (~50%) of preadipocytes. Gene expression analyses in proliferating preadipocytes (i.e., prior to hormonal induction of terminal differentiation) revealed that monocytes down-regulated mRNA levels of CCAAT/enhancer binding protein, alpha (C/EBPα) and up-regulated mRNA levels of G0/G1 switch 2 (G0S2) message, genes important for the regulation of adipogenesis and the cell cycle. These data indicate that circulating peripheral blood monocytes can disrupt adipogenesis by interfering with a critical step in C/EBPα and G0S2 transcription required for preadipocytes to make the transition from proliferation to differentiation. Interactions between preadipocytes and monocytes also increased the inflammatory cytokines IL-6 and IL-8, as well as a novel chemotactic cytokine, CXCL1. Additionally, the levels of both IL-6 and CXCL1 were highest when preadipocytes and monocytes were cultured together, compared to each cell in culture alone. Such cross-talk amplifies the production of mediators of tissue inflammation. PMID:21869759

NRF2 Signaling Negatively Regulates Phorbol-12-Myristate-13-Acetate (PMA-Induced Differentiation of Human Monocytic U937 Cells into Pro-Inflammatory Macrophages.

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Min-Gu Song

Full Text Available Blood monocytes are recruited to injured tissue sites and differentiate into macrophages, which protect against pathogens and repair damaged tissues. Reactive oxygen species (ROS are known to be an important contributor to monocytes' differentiation and macrophages' function. NF-E2-related factor 2 (NRF2, a transcription factor regulating cellular redox homeostasis, is known to be a critical modulator of inflammatory responses. We herein investigated the role of NRF2 in macrophage differentiation using the human monocytic U937 cell line and phorbol-12-myristate-13-acetate (PMA. In U937 cells with NRF2 silencing, PMA-stimulated cell adherence was significantly facilitated when compared to control U937 cells. Both transcript and protein levels for pro-inflammatory cytokines, including interleukine-1β (IL-1β, IL-6, and tumor necrosis factor-α (TNFα were highly elevated in PMA-stimulated NRF2-silenced U937 compared to the control. In addition, PMA-inducible secretion of monocyte chemotactic protein 1 (MCP-1 was significantly high in NRF2-silenced U937. As an underlying mechanism, we showed that NRF2-knockdown U937 retained high levels of cellular ROS and endoplasmic reticulum (ER stress markers expression; and subsequently, PMA-stimulated levels of Ca2+ and PKCα were greater in NRF2-knockdown U937 cells, which caused enhanced nuclear accumulation of nuclear factor-ҡB (NFҡB p50 and extracellular signal-regulated kinase (ERK-1/2 phosphorylation. Whereas the treatment of NRF2-silenced U937 cells with pharmacological inhibitors of NFҡB or ERK1/2 largely blocked PMA-induced IL-1β and IL-6 expression, indicating that these pathways are associated with cell differentiation. Taken together, our results suggest that the NRF2 system functions to suppress PMA-stimulated U937 cell differentiation into pro-inflammatory macrophages and provide evidence that the ROS-PKCα-ERK-NFҡB axis is involved in PMA-facilitated differentiation of NRF2-silenced U937

Meisoindigo, but not its core chemical structure indirubin, inhibits zebrafish interstitial leukocyte chemotactic migration.

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Ye, Baixin; Xiong, Xiaoxing; Deng, Xu; Gu, Lijuan; Wang, Qiongyu; Zeng, Zhi; Gao, Xiang; Gao, Qingping; Wang, Yueying

2017-12-01

Inflammatory disease is a big threat to human health. Leukocyte chemotactic migration is required for efficient inflammatory response. Inhibition of leukocyte chemotactic migration to the inflammatory site has been shown to provide therapeutic targets for treating inflammatory diseases. Our study was designed to discover effective and safe compounds that can inhibit leukocyte chemotactic migration, thus providing possible novel therapeutic strategy for treating inflammatory diseases. In this study, we used transgenic zebrafish model (Tg:zlyz-EGFP line) to visualize the process of leukocyte chemotactic migration. Then, we used this model to screen the hit compound and evaluate its biological activity on leukocyte chemotactic migration. Furthermore, western blot analysis was performed to evaluate the effect of the hit compound on the AKT or ERK-mediated pathway, which plays an important role in leukocyte chemotactic migration. In this study, using zebrafish-based chemical screening, we identified that the hit compound meisoindigo (25 μM, 50 μM, 75 μM) can significantly inhibit zebrafish leukocyte chemotactic migration in a dose-dependent manner (p = 0.01, p = 0.0006, p migration (p = 0.43). Furthermore, our results unexpectedly showed that indirubin, the core structure of meisoindigo, had no significant effect on zebrafish leukocyte chemotactic migration (p = 0.6001). Additionally, our results revealed that meisoindigo exerts no effect on the Akt or Erk-mediated signalling pathway. Our results suggest that meisoindigo, but not indirubin, is effective for inhibiting leukocyte chemotactic migration, thus providing a potential therapeutic agent for treating inflammatory diseases.

The proliferative human monocyte subpopulation contains osteoclast precursors

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Lari, Roya; Kitchener, Peter D; Hamilton, John A

2009-01-01

Introduction Immediate precursors of bone-resorbing osteoclasts are cells of the monocyte/macrophage lineage. Particularly during clinical conditions showing bone loss, it would appear that osteoclast precursors are mobilized from bone marrow into the circulation prior to entering tissues undergoing such loss. The observed heterogeneity of peripheral blood monocytes has led to the notion that different monocyte subpopulations may have special or restricted functions, including as osteoclast precursors. Methods Human peripheral blood monocytes were sorted based upon their degree of proliferation and cultured in macrophage colony-stimulating factor (M-CSF or CSF-1) and receptor activator of nuclear factor-kappa-B ligand (RANKL). Results The monocyte subpopulation that is capable of proliferation gave rise to significantly more multinucleated, bone-resorbing osteoclasts than the bulk of the monocytes. Conclusions Human peripheral blood osteoclast precursors reside in the proliferative monocyte subpopulation. PMID:19222861

Dynamics of the Chemotactic Boycott Effect

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Cisneros, Luis; Wolgemuth, Charles; Tuval, Idan

2005-03-01

Aerobic bacteria often live in thin fluid layers on irregular surfaces, near solid-air-water contact lines where the interplay between fluid interface geometry, nutrient transport, and chemotaxis is central to the micro-ecology. To elucidate these processes, we use the simplified geometry of a sessile drop and provide direct experimental evidence for the ``chemotactic Boycott effect" in suspensions of B. subtilis: upward oxygentaxis toward the drop surface leads to accumulation of cells in a thin layer, which flows down to the contact line and produces there a persistent vortex which traps cells near the meniscus. These phenomena are explained quantitatively with a mathematical model consisting of coupled oxygen diffusion and consumption, chemotaxis, and viscous fluid dynamics; they are shown to be associated with a singularity in the chemotactic dynamics at the contact line.

Monocytes can be induced by lipopolysaccharide-triggered T lymphocytes to express functional factor VII/VIIa protease activity

OpenAIRE

1984-01-01

In the present study we demonstrate that human monocytes can be induced by the model stimulus, lipopolysaccharide (LPS), to produce and assemble on their surface functional Factor VII/VIIa. This protease was not induced in relatively purified monocytes alone following exposure to LPS; but was induced in the presence of Leu-3a positive helper/inducer T cells. The Factor VII/VIIa protease activity represented 35-40% of the potential initiating activity for the extrinsic coagulation pathway and ...

Human monocytes undergo functional re-programming during sepsis mediated by hypoxia-inducible factor-1α.

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Shalova, Irina N; Lim, Jyue Yuan; Chittezhath, Manesh; Zinkernagel, Annelies S; Beasley, Federico; Hernández-Jiménez, Enrique; Toledano, Victor; Cubillos-Zapata, Carolina; Rapisarda, Annamaria; Chen, Jinmiao; Duan, Kaibo; Yang, Henry; Poidinger, Michael; Melillo, Giovanni; Nizet, Victor; Arnalich, Francisco; López-Collazo, Eduardo; Biswas, Subhra K

2015-03-17

Sepsis is characterized by a dysregulated inflammatory response to infection. Despite studies in mice, the cellular and molecular basis of human sepsis remains unclear and effective therapies are lacking. Blood monocytes serve as the first line of host defense and are equipped to recognize and respond to infection by triggering an immune-inflammatory response. However, the response of these cells in human sepsis and their contribution to sepsis pathogenesis is poorly understood. To investigate this, we performed a transcriptomic, functional, and mechanistic analysis of blood monocytes from patients during sepsis and after recovery. Our results revealed the functional plasticity of monocytes during human sepsis, wherein they transited from a pro-inflammatory to an immunosuppressive phenotype, while enhancing protective functions like phagocytosis, anti-microbial activity, and tissue remodeling. Mechanistically, hypoxia inducible factor-1α (HIF1α) mediated this functional re-programming of monocytes, revealing a potential mechanism for their therapeutic targeting to regulate human sepsis. Copyright © 2015 Elsevier Inc. All rights reserved.

Zinc oxide nanoparticles induce migration and adhesion of monocytes to endothelial cells and accelerate foam cell formation

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Suzuki, Yuka; Tada-Oikawa, Saeko [Graduate School of Regional Innovation Studies, Mie University, Tsu (Japan); Ichihara, Gaku [Department of Occupational and Environmental Health, Nagoya University Graduate School of Medicine, Nagoya (Japan); Yabata, Masayuki; Izuoka, Kiyora [Graduate School of Regional Innovation Studies, Mie University, Tsu (Japan); Suzuki, Masako; Sakai, Kiyoshi [Nagoya City Public Health Research Institute, Nagoya (Japan); Ichihara, Sahoko, E-mail: saho@gene.mie-u.ac.jp [Graduate School of Regional Innovation Studies, Mie University, Tsu (Japan)

2014-07-01

Metal oxide nanoparticles are widely used in industry, cosmetics, and biomedicine. However, the effects of exposure to these nanoparticles on the cardiovascular system remain unknown. The present study investigated the effects of nanosized TiO{sub 2} and ZnO particles on the migration and adhesion of monocytes, which are essential processes in atherosclerogenesis, using an in vitro set-up of human umbilical vein endothelial cells (HUVECs) and human monocytic leukemia cells (THP-1). We also examined the effects of exposure to nanosized metal oxide particles on macrophage cholesterol uptake and foam cell formation. The 16-hour exposure to ZnO particles increased the level of monocyte chemotactic protein-1 (MCP-1) and induced the migration of THP-1 monocyte mediated by increased MCP-1. Exposure to ZnO particles also induced adhesion of THP-1 cells to HUVECs. Moreover, exposure to ZnO particles, but not TiO{sub 2} particles, upregulated the expression of membrane scavenger receptors of modified LDL and increased cholesterol uptake in THP-1 monocytes/macrophages. In the present study, we found that exposure to ZnO particles increased macrophage cholesterol uptake, which was mediated by an upregulation of membrane scavenger receptors of modified LDL. These results suggest that nanosized ZnO particles could potentially enhance atherosclerogenesis and accelerate foam cell formation. - Highlights: • Effects of metal oxide nanoparticles on foam cell formation were investigated. • Exposure to ZnO nanoparticles induced migration and adhesion of monocytes. • Exposure to ZnO nanoparticles increased macrophage cholesterol uptake. • Expression of membrane scavenger receptors of modified LDL was also increased. • These effects were not observed after exposure to TiO{sub 2} nanoparticles.

Strenuous physical exercise adversely affects monocyte chemotaxis

DEFF Research Database (Denmark)

Czepluch, Frauke S; Barres, Romain; Caidahl, Kenneth

2011-01-01

Physical exercise is important for proper cardiovascular function and disease prevention, but it may influence the immune system. We evaluated the effect of strenuous exercise on monocyte chemotaxis. Monocytes were isolated from blood of 13 young, healthy, sedentary individuals participating...... in a three-week training program which consisted of repeated exercise bouts. Monocyte chemotaxis and serological biomarkers were investigated at baseline, after three weeks training and after four weeks recovery. Chemotaxis towards vascular endothelial growth factor-A (VEGF-A) and transforming growth factor...

Enhanced neutrophil chemotactic activity after bronchial challenge in subjects with grain dust-induced asthma.

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Park, H S; Jung, K S

1998-03-01

There have been few reports suggesting involvement of neutrophils in induction of bronchoconstriction after inhalation of grain dust. To understand the role of neutrophils in pathogenesis of grain dust-induced asthma. We observed serum neutrophil chemotactic activity during grain dust-bronchoprovocation tests in six asthmatic subjects with positive bronchial challenges (group I). They were compared with those of six symptomatic subjects from the same workplace with negative bronchial challenges (group II). After grain dust inhalation, serum neutrophil chemotactic activity significantly increased at 30 minutes (P = .028), and then decreased to baseline level at 240 minutes (P = .028) in five subjects of group I having isolated early asthmatic responses. Enhanced neutrophil chemotactic activity was persistent for up to 240 minutes in one asthmatic subject having both early and late asthmatic responses. There was, however, no significant change in serum neutrophil chemotactic activity during bronchial challenges in subjects of group II. Pre-incubation of sera with anti-interleukin-8 (IL-8) antibody did not affect the neutrophil chemotactic activity results of group I subjects. These results suggest that enhanced neutrophil chemotactic activity distinct from IL-8 may contribute to significant bronchoconstriction induced by grain dust.

Urease plays an important role in the chemotactic motility of Helicobacter pylori in a viscous environment.

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Nakamura, H; Yoshiyama, H; Takeuchi, H; Mizote, T; Okita, K; Nakazawa, T

1998-10-01

Helicobacter pylori exhibits chemotactic responses to urea, flurofamide, acetohydroxamic acid, and sodium bicarbonate. In buffer, the chemotactic activities of a urease-positive strain were higher than those of the isogenic urease-negative strain. Moreover, the chemotactic activities of the urease-positive strain were increased in a viscous solution containing 3% polyvinylpyrrolidone, whereas those of the urease-negative mutant were not. These results are in accordance with the fact that the mutant strain did not show swarming in motility agar regardless of having flagella. Incubation of the wild-type strain with flurofamide resulted in partial inhibition of the chemotactic activities in the viscous solution. In addition, incubation with acetohydroxamic acid, a low-molecular-weight, diffusible urease inhibitor, resulted in complete loss of chemotactic activity in the viscous solution. The inhibition of the chemotactic activity by urease inhibitors paralleled the inhibition of urease. The chemotactic activity of H. pylori was also inhibited by the proton carrier carbonyl cyanide m-chlorophenylhydrazone, showing that H. pylori utilizes proton motive force for motility. These results indicate that cytoplasmic urease plays an important role in the chemotactic motility of H. pylori under a condition that mimics the ecological niche of the bacterium, the gastric mucous layer.

Alveolar macrophage-epithelial cell interaction following exposure to atmospheric particles induces the release of mediators involved in monocyte mobilization and recruitment

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Mukae Hiroshi

2005-08-01

Full Text Available Abstract Background Studies from our laboratory have shown that human alveolar macrophages (AM and bronchial epithelial cells (HBEC exposed to ambient particles (PM10 in vitro increase their production of inflammatory mediators and that supernatants from PM10-exposed cells shorten the transit time of monocytes through the bone marrow and promote their release into the circulation. Methods The present study concerns co-culture of AM and HBEC exposed to PM10 (EHC-93 and the production of mediators involved in monocyte kinetics measured at both the mRNA and protein levels. The experiments were also designed to determine the role of the adhesive interaction between these cells via the intercellular adhesion molecule (ICAM-1 in the production of these mediators. Results AM/HBEC co-cultures exposed to 100 μg/ml of PM10 for 2 or 24 h increased their levels of granulocyte-macrophage colony-stimulating factor (GM-CSF, M-CSF, macrophage inflammatory protein (MIP-1β, monocyte chemotactic protein (MCP-1, interleukin (IL-6 and ICAM-1 mRNA, compared to exposed AM or HBEC mono-cultures, or control non-exposed co-cultures. The levels of GM-CSF, M-CSF, MIP-1β and IL-6 increased in co-cultured supernatants collected after 24 h exposure compared to control cells (p 10-induced increase in co-culture mRNA expression. Conclusion We conclude that an ICAM-1 independent interaction between AM and HBEC, lung cells that process inhaled particles, increases the production and release of mediators that enhance bone marrow turnover of monocytes and their recruitment into tissues. We speculate that this interaction amplifies PM10-induced lung inflammation and contributes to both the pulmonary and systemic morbidity associated with exposure to air pollution.

Monocytic leukemias.

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Shaw, M T

1980-05-01

The monocytic leukemias may be subdivided into acute monocytic leukemia, acute myelomonocytic leukemia, and subacute and chronic myelomonocytic leukemia. The clinical features of acute monocytic and acute myelomonocytic leukemias are similar and are manifestations of bone marrow failure. Gingival hypertrophy and skin infiltration are more frequent in acute monocytic leukemia. Cytomorphologically the blast cells in acute monocytic leukemia may be undifferentiated or differentiated, whereas in the acute myelomonocytic variety there are mixed populations of monocytic and myeloblastic cells. Cytochemical characteristics include strongly positive reactions for nonspecific esterase, inhibited by fluoride. The functional characteristics of acute monocytic and acute myelomonocytic cells resemble those of monocytes and include glass adherence and phagocytoses, the presence of Fc receptors for IgG and C'3, and the production of colony stimulating activity. Subacute and chronic myelomonocytic leukemias are insidious and slowly progressive diseases characterized by anemia and peripheral blood monocytosis. Atypical monocytes called paramyeloid cells are characteristic. The drugs used in the treatment of acute monocytic and acute myelomonocytic leukemias include cytosine arabinoside, the anthracyclines, and VP 16-213. Drug therapy in subacute and chronic myelomonocytic leukemias is not usually indicated, although VP 16-213 has been claimed to be effective.

EFFECTS OF SECRETABLE PLACENTAL FACTORS UPON SECRETION OF CYTOKINES BY THP-1 MONOCYTE-LIKE CELLS

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Ya. S. Onokhina

2013-01-01

Full Text Available Abstract. Мonocytes in feto-placental circulation are exposed to factors secreted by placental tissue. These factors influence monocyte functions in pregnancy. In present study, an in vitro model (monocyte-like THP-1 cells was used for assessing effects of soluble placental factors obtained from women with physiological pregnancies, or preeclampsia cases. The following effects of placental factors were revealed: increased secretion of VEGF by THP-1 cells along with decreased secretion of IL-6, IL-8 and MCP-1 under the influence of placental factors from the I. trimester of pregnancy in comparison with III. trimester. Secretion of IL-6 and MCP-1 by THP-1 cells was increased, and secretion of soluble TNFRII was decreased upon co-cultivation with soluble placental factors from the women with preeclampsia, as compared with placental products from physiological pregnancies.The work is supported by grants ГК № 02.740.11.0711 from Ministry of Education and Science, and НШ-3594.2010.7 grant from the President of Russian Federation.

Defect of netrophil chemotactic function is one of the etiology of aggressive periodontitis.

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Yanti Rusyanti

2016-06-01

Full Text Available Characteristic of progressive destructive periodontal tissue in Aggressive Periodontitis is a features of disruption of the host-homeostasis as the results of imbalance between host response and specific bacterial pathogenic which presents at gingival sulcus. The objective of this study was to evaluate netrophil function of  Aggressive periodontitis molecularly by means of gen polimorphism of Formyl Peptide Receptor (FPR1 at the surface of netrophil cell, the level of IL-8 and netrophil chemotactic. The results of  the study  can be used as an early detection, prevention or to arrest tissue destruction and to restore a health-associated homeostasis in order to get better prognosis of Aggressive Periodontitis. The study was conducted during 20 months in Periodontic Clinic Dental Hospital, Faculty of Dentistry, Padjadjaran University, Genetica Moleculer Medical Laboratory of Research Institution Padjadjaran University Bandung. Research design used case control methode and sample selection is done in concecutive sampling of 32 aggressive periodontitis patients and 29 non aggressive periodontitis patients who were included in the inclusion criteria. Research materials were venous blood and gingival crevicular fluid. PCR-Sequensing methode was used to asses of gene FPR1 Polimorphism. ELISA methode was used to measure IL-8 level in gingival crevicular fluid, and Human CD66abce Microbead Kit by MACS Separation methode was used to asses netrophil chemotactic. Chi-square test, Fisher’s exact, unpaired t tests were employed to analyse the differences of  characteristic, allele frequencies and genotypic, bivariate analysis to analyse of risk factors and biserial point correlation to analyse correlation between risk factors. The results showed the existence of c576T>C>G gene FPR1 polymorphism 5.040 time-fold (p=0.006; OR=5.040 while the down regulation of IL-8( ≤0.064 pg/µl is 34.5 times-fold of having aggressive periodontitis (OR=34, and c576T

Transport of Chemotactic Bacteria in Porous Media with Structured Heterogeneity

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Ford, R. M.; Wang, M.; Liu, J.; Long, T.

2008-12-01

Chemical contaminants that become trapped in low permeability zones (e.g. clay lenses) are difficult to remediate using conventional pump-and-treat approaches. Chemotactic bacteria that are transported by groundwater through more permeable regions may migrate toward these less permeable zones in response to chemical gradients created by contaminant diffusion from the low permeability source, thereby enhancing the remediation process by directing bacteria to the contaminants they degrade. What effect does the heterogeneity associated with coarse- and fine-grained layers that are characteristic of natural groundwater environments have on the transport of microorganisms and their chemotactic response? To address this question experiments were conducted over a range of scales from a single capillary tube to a laboratory- scale column in both static and flowing systems with and without chemoattractant gradients. In static capillary assays, motile bacteria accumulated at the interface between an aqueous solution and a suspension of agarose particulates. In microfluidic devices with an array of staggered cylinders, chemotactic bacteria migrated transverse to flow in response to a chemoattractant gradient. In sand columns packed with a coarse-grained core and surrounded by a fine-grained annulus, chemotactic bacteria migrated preferentially toward a chemoattractant source along the centerline. Mathematical models and computer simulations were developed to analyze the experimental observations in terms of transport parameters from the advection- disperson-sorption equation.

Postprandial Monocyte Activation in Individuals With Metabolic Syndrome

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Khan, Ilvira M.; Pokharel, Yashashwi; Dadu, Razvan T.; Lewis, Dorothy E.; Hoogeveen, Ron C.; Wu, Huaizhu

2016-01-01

Context: Postprandial hyperlipidemia has been suggested to contribute to atherogenesis by inducing proinflammatory changes in monocytes. Individuals with metabolic syndrome (MS), shown to have higher blood triglyceride concentration and delayed triglyceride clearance, may thus have increased risk for development of atherosclerosis. Objective: Our objective was to examine fasting levels and effects of a high-fat meal on phenotypes of monocyte subsets in individuals with obesity and MS and in healthy controls. Design, Setting, Participants, Intervention: Individuals with obesity and MS and gender- and age-matched healthy controls were recruited. Blood was collected from participants after an overnight fast (baseline) and at 3 and 5 hours after ingestion of a high-fat meal. At each time point, monocyte phenotypes were examined by multiparameter flow cytometry. Main Outcome Measures: Baseline levels of activation markers and postprandial inflammatory response in each of the three monocyte subsets were measured. Results: At baseline, individuals with obesity and MS had higher proportions of circulating lipid-laden foamy monocytes than controls, which were positively correlated with fasting triglyceride levels. Additionally, the MS group had increased counts of nonclassical monocytes, higher CD11c, CX3CR1, and human leukocyte antigen-DR levels on intermediate monocytes, and higher CCR5 and tumor necrosis factor-α levels on classical monocytes in the circulation. Postprandial triglyceride increases in both groups were paralleled by upregulation of lipid-laden foamy monocytes. MS, but not control, subjects had significant postprandial increases of CD11c and percentages of IL-1β+ and tumor necrosis factor-α+ cells in nonclassical monocytes. Conclusions: Compared to controls, individuals with obesity and MS had increased fasting and postprandial monocyte lipid accumulation and activation. PMID:27575945

Effects of transforming growth factor-beta on long-term human cord blood monocyte cultures

International Nuclear Information System (INIS)

Orcel, P.; Bielakoff, J.; De Vernejoul, M.C.

1990-01-01

Transforming growth factor-beta (TGF-beta) modulates growth and differentiation in many cell types and is abundant in bone matrix. We recently showed that human cord blood monocytes cultured in the presence of 1,25(OH)2D3 acquire some features of osteoclast precursors. Since TGF-beta has been shown to influence bone resorption in organ culture, we have studied the effect of TGF-beta (1-1,000 pg/ml) on cord blood monocyte cultures. These cells were cultured on plastic substrate during 3 weeks in the presence of 20% horse serum and 10(-9) M 1,25(OH)2D3. TGF-beta, from a concentration of 10 pg/ml in the culture medium, decreased in a dose dependent manner the formation of multinucleated cells. At a concentration of TGF-beta of 1 ng/ml, the multinucleated cells were reduced to 2.1% +/- 0.3%, compared to 19.3% +/- 1.5% in control cultures. TGF-beta inhibited in a dose-dependent manner the proliferation of cord blood monocytes as assessed by 3H-thymidine incorporation at 7 and 14 days of culture. The fusion index was also decreased by 3 weeks of treatment with TGF-beta. Indomethacin did not reverse the inhibitory effects of TGF-beta. The expression of the osteoclastic phenotype was assessed using two different antibodies: 23C6, a monoclonal antibody directed against the vitronectin receptor, which is highly expressed by osteoclasts but not by adult monocytes, and an antibody to HLA-DR, which is not present on osteoclast. TGF-beta decreased the expression of HLA-DR and increased in a dose-dependent manner the proportion of 23C6-labeled cells; these results suggest that TGF-beta could modulate a differentiation effect to the osteoclastic phenotype. However, when cord blood monocytes were cultured on devitalized rat calvariae prelabeled with 45Ca, TGF-beta did not induce any 45Ca release from bone cultured with monocytes

A novel dioxygenation product of arachidonic acid possesses potent chemotactic activity for human polymorphonuclear leukocytes.

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Shak, S; Perez, H D; Goldstein, I M

1983-12-25

We have found that a novel dioxygenation product of arachidonic acid, 8(S),15(S)-dihydroxy-5,11-cis-9,13-trans-eicosatetraenoic acid (8,15-diHETE), possesses chemotactic activity for human polymorphonuclear leukocytes comparable to that of leukotriene B4. Authentic 8,15-diHETE, identified by gas chromatography-mass spectrometry, was prepared by treating arachidonic acid with soybean lipoxygenase and was purified by reverse-phase high performance liquid chromatography. Using a "leading front" assay, 8,15-diHETE exhibited significant chemotactic activity at a concentration of 5.0 ng/ml. Maximum chemotactic activity was observed at a concentration of 30 ng/ml. The 8,15-diHETE generated by mixed human leukocytes after stimulation with arachidonic acid and the calcium ionophore, A23187, exhibited quantitatively similar chemotactic activity. Two synthetic all-trans conjugated isomers of 8,15-diHETE, however, were not chemotactic at concentrations up to 500 ng/ml. In contrast to its potent chemotactic activity, 8,15-diHETE (at concentrations up to 10 micrograms/ml) was relatively inactive with respect to its ability to provoke either degranulation or generation of superoxide anion radicals by cytochalasin B-treated leukocytes. Both leukotriene B4 and 8,15-diHETE may be important mediators of inflammation.

High-Density Lipoprotein Reduction Differentially Modulates to Classical and Nonclassical Monocyte Subpopulations in Metabolic Syndrome Patients and in LPS-Stimulated Primary Human Monocytes In Vitro

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Grün, Johanna L.; Manjarrez-Reyna, Aaron N.; Gómez-Arauz, Angélica Y.; Leon-Cabrera, Sonia; Bueno-Hernández, Nallely; Islas-Andrade, Sergio

2018-01-01

The effect of metabolic syndrome on human monocyte subpopulations has not yet been studied. Our main goal was to examine monocyte subpopulations in metabolic syndrome patients, while also identifying the risk factors that could directly influence these cells. Eighty-six subjects were divided into metabolic syndrome patients and controls. Monocyte subpopulations were quantified by flow cytometry, and interleukin- (IL-) 1β secretion levels were measured by ELISA. Primary human monocytes were cultured in low or elevated concentrations of high-density lipoprotein (HDL) and stimulated with lipopolysaccharide (LPS). The nonclassical monocyte (NCM) percentage was significantly increased in metabolic syndrome patients as compared to controls, whereas classical monocytes (CM) were reduced. Among all metabolic syndrome risk factors, HDL reduction exhibited the most important correlation with monocyte subpopulations and then was studied in vitro. Low HDL concentration reduced the CM percentage, whereas it increased the NCM percentage and IL-1β secretion in LPS-treated monocytes. The LPS effect was abolished when monocytes were cultured in elevated HDL concentrations. Concurring with in vitro results, IL-1β serum values significantly increased in metabolic syndrome patients with low HDL levels as compared to metabolic syndrome patients without HDL reduction. Our data demonstrate that HDL directly modulates monocyte subpopulations in metabolic syndrome. PMID:29850624

High-Density Lipoprotein Reduction Differentially Modulates to Classical and Nonclassical Monocyte Subpopulations in Metabolic Syndrome Patients and in LPS-Stimulated Primary Human Monocytes In Vitro

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Johanna L. Grün

2018-01-01

Full Text Available The effect of metabolic syndrome on human monocyte subpopulations has not yet been studied. Our main goal was to examine monocyte subpopulations in metabolic syndrome patients, while also identifying the risk factors that could directly influence these cells. Eighty-six subjects were divided into metabolic syndrome patients and controls. Monocyte subpopulations were quantified by flow cytometry, and interleukin- (IL- 1β secretion levels were measured by ELISA. Primary human monocytes were cultured in low or elevated concentrations of high-density lipoprotein (HDL and stimulated with lipopolysaccharide (LPS. The nonclassical monocyte (NCM percentage was significantly increased in metabolic syndrome patients as compared to controls, whereas classical monocytes (CM were reduced. Among all metabolic syndrome risk factors, HDL reduction exhibited the most important correlation with monocyte subpopulations and then was studied in vitro. Low HDL concentration reduced the CM percentage, whereas it increased the NCM percentage and IL-1β secretion in LPS-treated monocytes. The LPS effect was abolished when monocytes were cultured in elevated HDL concentrations. Concurring with in vitro results, IL-1β serum values significantly increased in metabolic syndrome patients with low HDL levels as compared to metabolic syndrome patients without HDL reduction. Our data demonstrate that HDL directly modulates monocyte subpopulations in metabolic syndrome.

Urease Plays an Important Role in the Chemotactic Motility of Helicobacter pylori in a Viscous Environment

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Nakamura, Hiroki; Yoshiyama, Hironori; Takeuchi, Hiroaki; Mizote, Tomoko; Okita, Kiwamu; Nakazawa, Teruko

1998-01-01

Helicobacter pylori exhibits chemotactic responses to urea, flurofamide, acetohydroxamic acid, and sodium bicarbonate. In buffer, the chemotactic activities of a urease-positive strain were higher than those of the isogenic urease-negative strain. Moreover, the chemotactic activities of the urease-positive strain were increased in a viscous solution containing 3% polyvinylpyrrolidone, whereas those of the urease-negative mutant were not. These results are in accordance with the fact that the ...

Stimulation of monocytes by placental microparticles involves Toll-like receptors and nuclear factor kappa-light-chain-enhancer of activated B cells

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Marianne Simone Joerger-Messerli

2014-04-01

Full Text Available Human pregnancy is accompanied by a mild systemic inflammatory response, which includes the activation of monocytes circulating in maternal blood. This response is exaggerated in preeclampsia, a placental-dependent disorder specific to human pregnancies. We and others showed that placental syncytiotrophoblast membrane microparticles (STBM generated in vitro from normal placentas stimulated peripheral blood monocytes, which suggests a contribution of STBM to the systemic maternal inflammation. Here, we analyzed the inflammatory potential of STBM prepared from preeclamptic placentas on primary monocytes and investigated the mode of action in vitro.STBM generated in vitro by placental villous explants of normal or preeclamptic placentas were co-incubated with human peripheral blood monocytes. In some cases, inhibitors of specific cellular functions or signaling pathways were used. The analysis of the monocytic response was performed by flow cytometry, enzyme-linked immunoassays, real-time PCR and fluorescence microscopy.STBM derived from preeclamptic placentas up-regulated the cell surface expression of CD54, and stimulated the secretion of the pro-inflammatory interleukin (IL-6 and IL-8 in a similar, dose-dependent manner as did STBM prepared from normal placentas. STBM bound to the cell surface of monocytes, but phagocytosis was not necessary for activation. STBM-induced cytokine secretion was impaired in the presence of inhibitors of toll-like receptor (TLR signaling or when nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB activation was blocked.Our results suggest that the inflammatory reaction in monocytes may be initiated by the interaction of STBM with TLRs, which in turn signal through NF-κB to mediate the transcription of genes coding for pro-inflammatory factors.

Cerium dioxide nanoparticles do not modulate the lipopolysaccharide-induced inflammatory response in human monocytes

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Hussain S

2012-03-01

Full Text Available Salik Hussain1,*, Faris Al-Nsour1,*, Annette B Rice1, Jamie Marshburn1, Zhaoxia Ji2, Jeffery I Zink2, Brenda Yingling1, Nigel J Walker3, Stavros Garantziotis11Clinical Research Unit, National Institute of Environmental Health Sciences/National Institute of Health, Research Triangle Park, NC, 2UC Center for Environmental Implications of Nanotechnology University of California, Los Angeles, CA, 3Division of National Toxicology Program, National Institute of Environmental Health Sciences/National Institute of Health, Research Triangle Park, NC, USA*Both are principal authorsBackground: Cerium dioxide (CeO2 nanoparticles have potential therapeutic applications and are widely used for industrial purposes. However, the effects of these nanoparticles on primary human cells are largely unknown. The ability of nanoparticles to exacerbate pre-existing inflammatory disorders is not well documented for engineered nanoparticles, and is certainly lacking for CeO2 nanoparticles. We investigated the inflammation-modulating effects of CeO2 nanoparticles at noncytotoxic concentrations in human peripheral blood monocytes.Methods: CD14+ cells were isolated from peripheral blood samples of human volunteers. Cells were exposed to either 0.5 or 1 µg/mL of CeO2 nanoparticles over a period of 24 or 48 hours with or without lipopolysaccharide (10 ng/mL prestimulation. Modulation of the inflammatory response was studied by measuring secreted tumor necrosis factor-alpha, interleukin-1beta, macrophage chemotactic protein-1, interferon-gamma, and interferon gamma-induced protein 10.Results: CeO2 nanoparticle suspensions were thoroughly characterized using dynamic light scattering analysis (194 nm hydrodynamic diameter, zeta potential analysis (-14 mV, and transmission electron microscopy (irregular-shaped particles. Transmission electron microscopy of CD14+ cells exposed to CeO2 nanoparticles revealed that these nanoparticles were efficiently internalized by monocytes and

MicroRNA-124 controls the proliferative, migratory, and inflammatory phenotype of pulmonary vascular fibroblasts.

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Wang, Daren; Zhang, Hui; Li, Min; Frid, Maria G; Flockton, Amanda R; McKeon, B Alexandre; Yeager, Michael E; Fini, Mehdi A; Morrell, Nicholas W; Pullamsetti, Soni S; Velegala, Sivareddy; Seeger, Werner; McKinsey, Timothy A; Sucharov, Carmen C; Stenmark, Kurt R

2014-01-03

Pulmonary hypertensive remodeling is characterized by excessive proliferation, migration, and proinflammatory activation of adventitial fibroblasts. In culture, fibroblasts maintain a similar activated phenotype. The mechanisms responsible for generation/maintenance of this phenotype remain unknown. We hypothesized that aberrant expression of microRNA-124 (miR-124) regulates this activated fibroblast phenotype and sought to determine the signaling pathways through which miR-124 exerts effects. We detected significant decreases in miR-124 expression in fibroblasts isolated from calves and humans with severe pulmonary hypertension. Overexpression of miR-124 by mimic transfection significantly attenuated proliferation, migration, and monocyte chemotactic protein-1 expression of hypertensive fibroblasts, whereas anti-miR-124 treatment of control fibroblasts resulted in their increased proliferation, migration, and monocyte chemotactic protein-1 expression. Furthermore, the alternative splicing factor, polypyrimidine tract-binding protein 1, was shown to be a direct target of miR-124 and to be upregulated both in vivo and in vitro in bovine and human pulmonary hypertensive fibroblasts. The effects of miR-124 on fibroblast proliferation were mediated via direct binding to the 3' untranslated region of polypyrimidine tract-binding protein 1 and subsequent regulation of Notch1/phosphatase and tensin homolog/FOXO3/p21Cip1 and p27Kip1 signaling. We showed that miR-124 directly regulates monocyte chemotactic protein-1 expression in pulmonary hypertension/idiopathic pulmonary arterial hypertension fibroblasts. Furthermore, we demonstrated that miR-124 expression is suppressed by histone deacetylases and that treatment of hypertensive fibroblasts with histone deacetylase inhibitors increased miR-124 expression and decreased proliferation and monocyte chemotactic protein-1 production. Stable decreases in miR-124 expression contribute to an epigenetically reprogrammed, highly

Shear Stress Enhances Chemokine Secretion from Chlamydia pneumoniae-infected Monocytes.

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Evani, Shankar J; Dallo, Shatha F; Murthy, Ashlesh K; Ramasubramanian, Anand K

2013-09-01

Chlamydia pneumoniae is a common respiratory pathogen that is considered a highly likely risk factor for atherosclerosis. C. pneumoniae is disseminated from the lung into systemic circulation via infected monocytes and lodges at the atherosclerotic sites. During transit, C. pneumoniae -infected monocytes in circulation are subjected to shear stress due to blood flow. The effect of mechanical stimuli on infected monocytes is largely understudied in the context of C. pneumoniae infection and inflammation. We hypothesized that fluid shear stress alters the inflammatory response of C. pneumoniae -infected monocytes and contributes to immune cell recruitment to the site of tissue damage. Using an in vitro model of blood flow, we determined that a physiological shear stress of 7.5 dyn/cm 2 for 1 h on C. pneumoniae -infected monocytes enhances the production of several chemokines, which in turn is correlated with the recruitment of significantly large number of monocytes. Taken together, these results suggest synergistic interaction between mechanical and chemical factors in C. pneumoniae infection and associated inflammation.

Quantitative analysis of the secretion of the MCP family of chemokines by muscle cells

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Henningsen, Jeanette; Pedersen, Bente Klarlund; Kratchmarova, Irina

2011-01-01

by Amino acids in Cell culture (SILAC) method for quantitative analysis resulted in the identification and generation of quantitative profiles of 59 growth factors and cytokines, including 9 classical chemokines. The members of the CC chemokine family of proteins such as monocyte chemotactic proteins 1, 2...

Journal of Biosciences | Indian Academy of Sciences

Indian Academy of Sciences (India)

Japanese encephalitis virus (JEV) induces human peripheral blood monocytes to secrete a chemotactic cytokine [human macrophage-derived factor (hMDF)] which causes chemotaxis of neutrophils. The only known assay for hMDF cannot quantify its level in samples, so an enzyme immunoassay has been standardized for ...

Optimal methylation noise for best chemotactic performance of E. coli

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Dev, Subrata; Chatterjee, Sakuntala

2018-03-01

In response to a concentration gradient of chemoattractant, E. coli bacterium modulates the rotational bias of flagellar motors which control its run-and-tumble motion, to migrate towards regions of high chemoattractant concentration. Presence of stochastic noise in the biochemical pathway of the cell has important consequences on the switching mechanism of motor bias, which in turn affects the runs and tumbles of the cell in a significant way. We model the intracellular reaction network in terms of coupled time evolution of three stochastic variables—kinase activity, methylation level, and CheY-P protein level—and study the effect of methylation noise on the chemotactic performance of the cell. In presence of a spatially varying nutrient concentration profile, a good chemotactic performance allows the cell to climb up the concentration gradient quickly and localize in the nutrient-rich regions in the long time limit. Our simulations show that the best performance is obtained at an optimal noise strength. While it is expected that chemotaxis will be weaker for very large noise, it is counterintuitive that the performance worsens even when noise level falls below a certain value. We explain this striking result by detailed analysis of CheY-P protein level statistics for different noise strengths. We show that when the CheY-P level falls below a certain (noise-dependent) threshold the cell tends to move down the concentration gradient of the nutrient, which has a detrimental effect on its chemotactic response. This threshold value decreases as noise is increased, and this effect is responsible for noise-induced enhancement of chemotactic performance. In a harsh chemical environment, when the nutrient degrades with time, the amount of nutrient intercepted by the cell trajectory is an effective performance criterion. In this case also, depending on the nutrient lifetime, we find an optimum noise strength when the performance is at its best.

Transcriptome analysis of monocyte-HIV interactions

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Tran Huyen

2010-06-01

Full Text Available Abstract Background During HIV infection and/or antiretroviral therapy (ART, monocytes and macrophages exhibit a wide range of dysfunctions which contribute significantly to HIV pathogenesis and therapy-associated complications. Nevertheless, the molecular components which contribute to these dysfunctions remain elusive. We therefore applied a parallel approach of genome-wide microarray analysis and focused gene expression profiling on monocytes from patients in different stages of HIV infection and/or ART to further characterise these dysfunctions. Results Processes involved in apoptosis, cell cycle, lipid metabolism, proteasome function, protein trafficking and transcriptional regulation were identified as areas of monocyte dysfunction during HIV infection. Individual genes potentially contributing to these monocyte dysfunctions included several novel factors. One of these is the adipocytokine NAMPT/visfatin, which we show to be capable of inhibiting HIV at an early step in its life cycle. Roughly half of all genes identified were restored to control levels under ART, while the others represented a persistent dysregulation. Additionally, several candidate biomarkers (in particular CCL1 and CYP2C19 for the development of the abacavir hypersensitivity reaction were suggested. Conclusions Previously described areas of monocyte dysfunction during HIV infection were confirmed, and novel themes were identified. Furthermore, individual genes associated with these dysfunctions and with ART-associated disorders were pinpointed. These genes form a useful basis for further functional studies concerning the contribution of monocytes/macrophages to HIV pathogenesis. One such gene, NAMPT/visfatin, represents a possible novel restriction factor for HIV. Background Both macrophages and T lymphocyte subsets express the CD4 receptor and either the CXCR4 and/or the CCR5 coreceptor which confer susceptibility to infection with the Human Immunodeficiency Virus

CD1 molecule expression on human monocytes induced by granulocyte-macrophage colony-stimulating factor.

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Kasinrerk, W; Baumruker, T; Majdic, O; Knapp, W; Stockinger, H

1993-01-15

In this paper we demonstrate that granulocyte-macrophage CSF (GM-CSF) specifically induces the expression of CD1 molecules, CD1a, CD1b and CD1c, upon human monocytes. CD1 molecules appeared upon monocytes on day 1 of stimulation with rGM-CSF, and expression was up-regulated until day 3. Monocytes cultured in the presence of LPS, FMLP, PMA, recombinant granulocyte-CSF, rIFN-gamma, rTNF-alpha, rIL-1 alpha, rIL-1 beta, and rIL-6 remained negative. The induction of CD1 molecules by rGM-CSF was restricted to monocytes, since no such effect was observed upon peripheral blood granulocytes, PBL, and the myeloid cell lines Monomac1, Monomac6, MV4/11, HL60, U937, THP1, KG1, and KG1A. CD1a mRNA was detectable in rGM-CSF-induced monocytes but not in those freshly isolated. SDS-PAGE and immunoblotting analyses of CD1a mAb VIT6 immunoprecipitate from lysate of rGM-CSF-activated monocytes revealed an appropriate CD1a polypeptide band of 49 kDa associated with beta 2-microglobulin. Expression of CD1 molecules on monocytes complements the distribution of these structures on accessory cells, and their specific induction by GM-CSF strengthens the suggestion that CD1 is a family of crucial structures required for interaction between accessory cells and T cells.

Colloidal silver nanoparticles/rhamnolipid (SNPRL) composite as novel chemotactic antibacterial agent.

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Bharali, P; Saikia, J P; Paul, S; Konwar, B K

2013-10-01

The antibacterial activity of silver nanoparticles and rhamnolipid are well known individually. In the present research, antibacterial and chemotactic activity due to colloidal silver nanoparticles (SNP), rhamnolipid (RL) and silver nanoparticles/rhamnolipid composite (SNPRL) were evaluated using Staphylococcus aureus (MTCC3160), Escherichia coli (MTCC40), Pseudomonas aeruginosa (MTCC8163) and Bacillus subtilis (MTCC441) as test strains. Further, the SNPRL nanoparticles were characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Fourier transform infrared spectroscopy (FTIR). The observation clearly indicates that SNPRL shows prominent antibacterial and chemotactic activity in comparison to all of its individual precursor components. Copyright © 2013 Elsevier B.V. All rights reserved.

Peripheral blood monocyte subsets predict antiviral response in chronic hepatitis C.

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Rodríguez-Muñoz, Y; Martín-Vílchez, S; López-Rodríguez, R; Hernández-Bartolomé, A; Trapero-Marugán, M; Borque, M J; Moreno-Otero, R; Sanz-Cameno, P

2011-10-01

Hepatitis C virus infection evolves into chronic progressive liver disease in a significant percentage of patients. Monocytes constitute a diverse group of myeloid cells that mediate innate and adaptive immune response. In addition to proinflammatory CD16+ monocytes, a Tie-2+ subgroup - Tie-2 expressing monocytes (TEMs) - that has robust proangiogenic potential has been recently defined. To study the heterogeneity of peripheral blood monocytes in chronic hepatitis C (CHC) patients and to examine their proposed pathophysiological roles on disease progression and response to antiviral therapy. We studied CD16+ and Tie-2+ peripheral monocyte subpopulations in 21 healthy subjects and 39 CHC patients in various stages of disease and responses to antiviral treatment using flow cytometry. Expression profiles of proangiogenic and tissue remodelling factors in monocyte supernatants were measured using ELISA and protein arrays. Intrahepatic expression of CD14, CD31 and Tie-2 was analysed using immunofluorescence. Increases of certain peripheral monocyte subsets were observed in the blood of CHC patients, wherein those cells with proinflammatory (CD16+) or proangiogenic (TEMs) potential expanded (P TEMs were significantly increased in nonresponders, particularly those with lower CD16 expression. In addition, many angiogenic factors were differentially expressed by peripheral monocytes from control or CHC patients, such as angiopoietin-1 and angiogenin (P TEMs were distinguished within portal infiltrates of CHC patients. These findings suggest for the first time the relevance of peripheral monocytes phenotypes for the achievement of response to treatment. Hence, the study of monocyte subset regulation might effect improved CHC prognoses and adjuvant therapies. © 2011 Blackwell Publishing Ltd.

Monocyte function is severely impaired by the fluorochrome calcein acetomethylester

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Czepluch, Frauke S.; Olieslagers, Serve J.F.; Waltenberger, Johannes

2007-01-01

For rapid chemotaxis quantification, cell prelabelling is often performed with the fluorochrome calcein acetomethylester (calcein AM). We investigated whether calcein AM-prelabelling is reliable for monocyte migration analysis. Human monocytes were either preexposed to calcein AM or unlabelled. Monocyte migration towards the potent chemoattractants transforming growth factor-β1 (TGF-β1) and N-formyl-Methionin-Leucin-Phenylalanin (fMLP) was assessed using a 48-well micro-chemotaxis chamber. For quantification, cells were visualized by light microscopy and counted. Surprisingly, random migration of calcein AM-prelabelled cells was significantly impaired compared to the unlabelled control. Accordingly, monocyte chemotaxis towards either TGF-β1 or fMLP dramatically declined. Adherence of calcein AM-labelled monocytes on plastic was also significantly decreased compared to control cells. As adhesion is regarded as an essential component of monocyte migration, the reduced migration observed in calcein AM-labelled monocytes might be explained by a fluorochrome-induced adhesion defect. Therefore, use of the fluorochrome calcein AM cannot be recommended for functional testing of monocytes

Vitamin D inhibits the growth of and virulence factor gene expression by Porphyromonas gingivalis and blocks activation of the nuclear factor kappa B transcription factor in monocytes.

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Grenier, D; Morin, M-P; Fournier-Larente, J; Chen, H

2016-06-01

Increasing evidence suggests that 1,25-dihydroxyvitamin D3 (1,25(OH)2 D3 ), a fat-soluble secosteroid hormone, has a positive impact on periodontal health through diverse mechanisms. The present study was aimed at investigating the effect of 1,25(OH)2 D3 on the growth of and virulence factor gene expression by the periodontopathogenic bacterium Porphyromonas gingivalis. The effect of 1,25(OH)2 D3 on P. gingivalis-mediated activation of nuclear factor kappa B (NF-κB) transcription factor in monocytes was also assessed. A broth microdilution assay was used to determine the antibacterial activity of 1,25(OH)2 D3 . The modulation of virulence factor gene expression in P. gingivalis was assessed by quantitative reverse transcription-polymerase chain reaction. NF-κB activation was assessed using a human monocytic cell line stably transfected with a luciferase reporter containing NF-κB binding sites. Minimal inhibitory concentrations of 1,25(OH)2 D3 against P. gingivalis ranged from 3.125 to 6.25 μg/mL. Moreover, a partial synergistic effect was observed when 1,25(OH)2 D3 was used in association with metronidazole. 1,25(OH)2 D3 attenuated the virulence of P. gingivalis by reducing the expression of genes coding for important virulence factors, including adhesins (fimA, hagA and hagB) and proteinases (rgpA, rgpB and kgp). 1,25(OH)2 D3 dose-dependently prevented P. gingivalis-induced NF-κB activation in a monocyte model. Our study suggested that 1,25(OH)2 D3 selectively inhibits the growth of and virulence factor gene expression by P. gingivalis, in addition to attenuating NF-κB activation by this periodontopathogen. This dual action on P. gingivalis and the inflammatory response of host cells may be of particular interest with a view to developing a novel and inexpensive preventive/therapeutic strategy. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Mycobacterium leprae upregulates IRGM expression in monocytes and monocyte-derived macrophages.

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Yang, Degang; Chen, Jia; Zhang, Linglin; Cha, Zhanshan; Han, Song; Shi, Weiwei; Ding, Ru; Ma, Lan; Xiao, Hong; Shi, Chao; Jing, Zhichun; Song, Ningjing

2014-08-01

Leprosy is caused by the infection of Mycobacterium leprae, which evokes a strong inflammatory response and leads to nerve damage. Immunity-related GTPase family M protein (IRGM) plays critical roles in controlling inflammation. The objective of the study was to investigate whether IRGM is involved in the infection of M. leprae. Levels of IRGM were assessed in M. leprae-infected CD4(+) T cells, monocytes, and monocyte-derived macrophages. Data revealed that both protein and mRNA levels of IRGM were increased in monocytes after M. leprae infection. Interestingly, monocyte-derived macrophages showed more prominent IRGM expression with M. leprae infection, whereas the bacteria did not affect IRGM in CD4(+) T cells. Furthermore, we assessed levels of IRGM in CD4(+) T cells and monocytes from 78 leprosy patients and 40 healthy controls, and observed upregulated protein level of IRGM in the monocytes from leprosy patients. Also, IRGM expression was inversely correlated with the severity of the disease. These findings suggested a close involvement of IRGM in M. leprae infection and indicated a potential mechanism of defending M. leprae infection.

Fish-oil-derived n-3 PUFAs reduce inflammatory and chemotactic adipokine-mediated cross-talk between co-cultured murine splenic CD8+ T cells and adipocytes.

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Monk, Jennifer M; Liddle, Danyelle M; De Boer, Anna A; Brown, Morgan J; Power, Krista A; Ma, David Wl; Robinson, Lindsay E

2015-04-01

Obese adipose tissue (AT) inflammation is characterized by dysregulated adipokine production and immune cell accumulation. Cluster of differentiation (CD) 8+ T cell AT infiltration represents a critical step that precedes macrophage infiltration. n-3 (ω-3) Polyunsaturated fatty acids (PUFAs) exert anti-inflammatory effects in obese AT, thereby disrupting AT inflammatory paracrine signaling. We assessed the effect of n-3 PUFAs on paracrine interactions between adipocytes and primary CD8+ T cells co-cultured at the cellular ratio observed in obese AT. C57BL/6 mice were fed either a 3% menhaden fish-oil + 7% safflower oil (FO) diet (wt:wt) or an isocaloric 10% safflower oil (wt:wt) control (CON) for 3 wk, and splenic CD8+ T cells were isolated by positive selection (via magnetic microbeads) and co-cultured with 3T3-L1 adipocytes. Co-cultures were unstimulated (cells alone), T cell receptor stimulated, or lipopolysaccharide (LPS) stimulated for 24 h. In LPS-stimulated co-cultures, FO reduced secreted protein concentrations of interleukin (IL)-6 (-42.6%), tumor necrosis factor α (-67%), macrophage inflammatory protein (MIP) 1α (-52%), MIP-1β (-62%), monocyte chemotactic protein (MCP) 1 (-23%), and MCP-3 (-19%) vs. CON, which coincided with a 74% reduction in macrophage chemotaxis toward secreted chemotaxins in LPS-stimulated FO-enriched co-culture-conditioned media. FO increased mRNA expression of the inflammatory signaling negative regulators monocyte chemoattractant 1-induced protein (Mcpip; +9.3-fold) and suppressor of cytokine signaling 3 (Socs3; +1.7-fold), whereas FO reduced activation of inflammatory transcription factors nuclear transcription factor κB (NF-κB) p65 and signal transducer and activator of transcription 3 (STAT3) by 27% and 33%, respectively. Finally, mRNA expression of the inflammasome components Caspase1 (-36.4%), Nod-like receptor family pyrin domain containing 3 (Nlrp3; -99%), and Il1b (-68.8%) were decreased by FO compared with CON (P �

Age-dependent alterations of monocyte subsets and monocyte-related chemokine pathways in healthy adults

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Trautwein Christian

2010-06-01

Full Text Available Abstract Background Recent experimental approaches have unraveled essential migratory and functional differences of monocyte subpopulations in mice. In order to possibly translate these findings into human physiology and pathophysiology, human monocyte subsets need to be carefully revisited in health and disease. In analogy to murine studies, we hypothesized that human monocyte subsets dynamically change during ageing, potentially influencing their functionality and contributing to immunosenescence. Results Circulating monocyte subsets, surface marker and chemokine receptor expression were analyzed in 181 healthy volunteers (median age 42, range 18-88. Unlike the unaffected total leukocyte or total monocyte counts, non-classical CD14+CD16+ monocytes significantly increased with age, but displayed reduced HLA-DR and CX3CR1 surface expression in the elderly. Classical CD14++CD16- monocyte counts did not vary dependent on age. Serum MCP-1 (CCL2, but not MIP1α (CCL3, MIP1β (CCL4 or fractalkine (CX3CL1 concentrations increased with age. Monocyte-derived macrophages from old or young individuals did not differ with respect to cytokine release in vitro at steady state or upon LPS stimulation. Conclusions Our study demonstrates dynamic changes of circulating monocytes during ageing in humans. The expansion of the non-classical CD14+CD16+ subtype, alterations of surface protein and chemokine receptor expression as well as circulating monocyte-related chemokines possibly contribute to the preserved functionality of the monocyte pool throughout adulthood.

Fibroblast growth factor 23 inhibits extrarenal synthesis of 1,25-dihydroxyvitamin D in human monocytes.

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Bacchetta, Justine; Sea, Jessica L; Chun, Rene F; Lisse, Thomas S; Wesseling-Perry, Katherine; Gales, Barbara; Adams, John S; Salusky, Isidro B; Hewison, Martin

2013-01-01

Vitamin D is a potent stimulator of monocyte innate immunity, and this effect is mediated via intracrine conversion of 25-hydroxyvitamin D (25OHD) to 1,25-dihydroxyvitamin D (1,25(OH)(2) D). In the kidney, synthesis of 1,25(OH)(2) D is suppressed by fibroblast growth factor 23 (FGF23), via transcriptional suppression of the vitamin D-activating enzyme 1α-hydroxylase (CYP27B1). We hypothesized that FGF23 also suppresses CYP27B1 in monocytes, with concomitant effects on intracrine responses to 1,25(OH)(2) D. Healthy donor peripheral blood mononuclear cell monocytes (PBMCm) and peritoneal dialysate monocyte (PDm) effluent from kidney disease patients were assessed at baseline to confirm the presence of mRNA for FGF23 receptors (FGFRs), with Klotho and FGFR1 being more strongly expressed than FGFR2/3/4 in both cell types. Immunohistochemistry showed coexpression of Klotho and FGFR1 in PBMCm and PDm, with this effect being enhanced following treatment with FGF23 in PBMCm but not PDm. Treatment with FGF23 activated mitogen-activated protein kinase (MAPK) and protein kinase B (Akt) pathways in PBMCm, demonstrating functional FGFR signaling in these cells. FGF23 treatment of PBMCm and PDm decreased expression of mRNA for CYP27B1. In PBMCm this was associated with downregulation of 25OHD to 1,25(OH)(2) D metabolism, and concomitant suppression of intracrine induced 24-hydroxylase (CYP24A1) and antibacterial cathelicidin (LL37). FGF23 suppression of CYP27B1 was particularly pronounced in PBMCm treated with interleukin-15 to stimulate synthesis of 1,25(OH)(2) D. These data indicate that FGF23 can inhibit extra-renal expression of CYP27B1 and subsequent intracrine responses to 1,25(OH)(2) D in two different human monocyte models. Elevated expression of FGF23 may therefore play a crucial role in defining immune responses to vitamin D and this, in turn, may be a key determinant of infection in patients with chronic kidney disease (CKD). Copyright © 2013 American Society for

[Peptide fragments of chemokine domain of fractalkine: effect on human monocyte migration].

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Kukhtina, N B; Aref'eva, T I; Ruleva, N Iu; Sidorova, M V; Az'muko, A A; Bespalova, Zh D; Krasnikova, T L

2012-01-01

Leukocyte chemotaxis to the area of tissue damage is mediated by chemokines. According to the primary structure, chemokines are divided into four families, fractalkine (CX3CL1) is the only one member of CX3C family and the only membrane-bound chemokine. Fractalkine molecule includes the extracellular N-terminal chemokine domain, mucin-like rod, the transmembrane and the intracellular domains. In membrane-bound state fractalkine has the properties of an adhesion molecule. Chemokine domain of fractalkine (CDF) is released from cell membrane by proteolysis, and this soluble form acts as a chemoattractant for leukocytes expressing fractalkine receptor CX3CR1. Fractalkine is involved in development of a number of pathological processes caused by inflammation, and therefore a search for fractalkine inhibitors is very important. For this purpose we identified several antigenic determinants--the fragments of CDF, and the following peptides were synthesized--P41-52 H-Leu-Glu-Thr-Arg-Gln-His-Arg-Leu-Phe-Cys-Ala-Asp-NH2, P53-60 H-Pro-Lys-Glu-Gln-Trp-Val-Lys-Asp-NH2 and P60-71 H-Asp-Ala-Met-Gln-His-Leu-Asp-Arg-Gln-Ala-Ala-Ala-NH2. The peptide effects on adhesion and migration of human peripheral blood monocytes expressing fractalkine receptors were investigated. In the presence of CDF and P41-52 we observed the increased adhesion and migration of monocytes compared with spontaneous values. Peptides P53-60 and P60-71 significantly inhibited monocyte adhesion and migration stimulated by CDF. Since the chemotactic activity of chemokines was shown to be dependent on their binding to glycosaminoglycans of the cell surface and extracellular matrix, the effect ofpeptides on the interaction of CDF with heparin was analyzed by ELISA. Peptide P41-52 competed with CDF for heparin binding, while peptides P53-60 and P60-71 had no significant activity.

Targeting Tumor Necrosis Factor-α with Adalimumab: Effects on Endothelial Activation and Monocyte Adhesion.

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Raghav Oberoi

Full Text Available It is well known that atherosclerotic inflammatory vascular disease is critically driven by oxidized lipids and cytokines. In this regard, tumor necrosis factor (TNF-α is known as a crucial mediator of early pro-atherosclerotic events. Epidemiologic data suggest that blockade of TNF-α has beneficial effects on vascular outcomes in patients with rheumatoid arthritis, however, detailed mechanistic studies are still lacking. This study aims to elucidate effects of TNF-α blockade by adalimumab-which is approved for several inflammatory disorders-on endothelial activation and monocyte adhesion under pro-atherosclerotic conditions.Phorbol myristate acetate (PMA differentiated THP-1 macrophages were stimulated with oxidized low density lipoprotein and subsequent analysis of this conditioned media (oxLDL CM revealed a strong release of TNF-α. The TNF-α rich supernatant led to activation of human umbilical vein endothelial cells (HUVEC as shown by enhanced expression of major adhesion molecules, such as vascular cell adhesion molecule-1 (VCAM-1, intercellular adhesion molecule-1 (ICAM-1 and E-selectin which was suppressed by the TNF-α inhibitor adalimumab. Accordingly, adalimumab effectively prevented THP-1 monocyte adhesion to endothelial cells under static as well as under flow conditions. Furthermore, adalimumab suppressed endothelial leakage as shown by Evan's blue diffusion across a confluent endothelial monolayer. Of note, after intraperitoneal injection we detected abundant deposition of fluorophore-labelled adalimumab in atherosclerotic plaques of hypercholesterolemic mice.Our results show that adalimumab prevents major inflammatory effects of TNF-α on endothelial activation, endothelial monocyte adhesion, endothelial leakage and therefore extends the therapeutic options of adalimumab to limit vascular inflammation.

Transfecting Human Monocytes with RNA.

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Dannull, Jens; Nair, Smita K

2016-01-01

Targeting monocytes as a delivery system for drugs or nucleic acids, and thereby harnessing their natural tissue-infiltrating capacity, has become an area of intense investigation in both basic and clinical research. Herein we describe an efficient method to deliver mRNA (messenger RNA) or siRNA (small interfering RNA) into human monocytes by electroporation. This method can be applied in the laboratory to monocytes isolated via magnetic bead-based techniques, or in a clinical setting using monocytes that were collected via counterflow centrifugation elutriation using the Elutra(®) Cell Separation System. We further demonstrate that electroporation of monocytes with RNA represents a robust and highly relevant approach to modify monocytes for cell-based therapies. Last, the procedure described can readily be adapted to monocytes from different species, hence facilitating research in animal models.

In vivo imaging of monocyte trafficking with 18F-fluorodeoxyglucose labeled monocytes

International Nuclear Information System (INIS)

Paik, Jin Young; Lee, Kyung Han; Han, Yu Mi; Choe, Yearn Seong; Kim, Byung Tae

2000-01-01

Since the ability to monitor in vivo monocyte trafficking would contribute to our understanding of the pathophysiology of various inflammatory disorders, we investigated the feasibility of labeling human monocytes with 18 F-FDG. Human monocytes were separated by Ficoll/Hypaque gradient and purity was assessed by flow cytometry. The influence of insulin and/or glucose on labeling efficiency was evaluated. Cell viability and activation was measured with trypan blue exclusion and hydrogen peroxide assays, respectively. Label stability was measured for up to 18 hr, and the effect of insulin pre-incubation on FDG washout was investigated. PET images were acquired in SD rats at various time points after injection of FDG labeled monocytes. Monocytes were >85% pure, and labeling efficiency was 35% for 1x106 cells after 40 min incubation with 2 mCi 18 F-FDG without insulin. Pre-incubation with 10∼100 nM insulin significantly increased FDG uptake which reached 400% of baseline levels, whereas presence of glucose or serum decreased FDG uptake. Labeled cells were >90% viable for up to 22 hr, and the labeling process did appear to significantly activate cells, Washout studies however, demonstrated gradual washout of the FDG from monocytes after initial uptake PET images of FDG labeled monocytes in SD rats showed consistent findings. Utilizing insulin effects on cellular glucose metabolism may be a feasible way of labeling monocytes with 18 F-FDG for PET imaging. However, gradual washout of FDG after initial uptake poses as a potential problem which needs to be addressed before practical application

Radiation-Induced Thymidine Phosphorylase Upregulation in Rectal Cancer Is Mediated by Tumor-Associated Macrophages by Monocyte Chemoattractant Protein-1 From Cancer Cells

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Kim, Tae-Dong; Li Ge; Song, Kyoung-Sub; Kim, Jin-Man; Kim, Jun-Sang; Kim, Jong-Seok; Yun, Eun-Jin; Park, Jong-Il; Park, Hae-Duck; Hwang, Byung-Doo; Lim, Kyu; Yoon, Wan-Hee

2009-01-01

Purpose: The mechanisms of thymidine phosphorylase (TP) regulation induced by radiation therapy (XRT) in various tumors are poorly understood. We investigated the effect and mechanisms of preoperative XRT on TP expression in rectal cancer tissues. Methods and Materials: TP expression and CD68 and monocyte chemoattractant protein-1 (MCP-1) levels in rectal cancer tissues and cancer cell lines were evaluated before and after XRT in Western blotting, immunohistochemistry, enzyme-linked immunoassay, and reverse transcription-polymerase chain reaction studies. Isolated peripheral blood monocytes were used in the study of chemotaxis under the influence of MCP-1 released by irradiated colon cancer cells. Results: Expression of TP was significantly elevated by 9 Gy of XRT in most rectal cancer tissues but not by higher doses of XRT. In keeping with the close correlation of the increase in both TP expression and the number of tumor-associated macrophages (TAMs), anti-TP immunoreactivity was found in the CD68-positive TAMs and not the neoplastic cells. Expression of MCP-1 was increased in most cases after XRT, and this increase was strongly correlated with TP expression. However, this increase in MCP-1 expression occurred in tumor cells and not stromal cells. The XRT upregulated MCP-1 mRNA and also triggered the release of MCP-1 protein from cultured colon cancer cells. The supernatant of irradiated colon cancer cells showed strong chemotactic activity for monocyte migration, but this activity was completely abolished by neutralizing antibody. Conclusions: Use of XRT induces MCP-1 expression in cancer cells, which causes circulating monocytes to be recruited into TAMs, which then upregulate TP expression in rectal cancer tissues

Circulating cytokines and cytokine receptors in infliximab treatment failure due to TNF-α independent Crohn disease

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Steenholdt, Casper; Coskun, Mehmet; Buhl, Sine

2016-01-01

-IFX antibodies. Circulating cytokines and cytokine receptors were assessed by enzyme-linked immunosorbent assay: granulocyte-macrophage colony-stimulating factor, interferon-γ, interleukin (IL)-1α, IL-1β, IL-1Ra, IL-6, IL-10, IL-12p70, soluble TNF receptor (sTNF-R) 1, sTNF-R2, IL-17A, and monocyte chemotactic...

Inhibition of the differentiation of monocyte-derived dendritic cells by human gingival fibroblasts.

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Sylvie Séguier

Full Text Available We investigated whether gingival fibroblasts (GFs can modulate the differentiation and/or maturation of monocyte-derived dendritic cells (DCs and analyzed soluble factors that may be involved in this immune modulation. Experiments were performed using human monocytes in co-culture with human GFs in Transwell® chambers or using monocyte cultures treated with conditioned media (CM from GFs of four donors. The four CM and supernatants from cell culture were assayed by ELISA for cytokines involved in the differentiation of dendritic cells, such as IL-6, VEGF, TGFβ1, IL-13 and IL-10. The maturation of monocyte-derived DCs induced by LPS in presence of CM was also studied. Cell surface phenotype markers were analyzed by flow cytometry. In co-cultures, GFs inhibited the differentiation of monocyte-derived DCs and the strength of this blockade correlated with the GF/monocyte ratio. Conditioned media from GFs showed similar effects, suggesting the involvement of soluble factors produced by GFs. This inhibition was associated with a lower stimulatory activity in MLR of DCs generated with GFs or its CM. Neutralizing antibodies against IL-6 and VEGF significantly (P<0.05 inhibited the inhibitory effect of CM on the differentiation of monocytes-derived DCs and in a dose dependent manner. Our data suggest that IL-6 is the main factor responsible for the inhibition of DCs differentiation mediated by GFs but that VEGF is also involved and constitutes an additional mechanism.

Curcumin as a natural regulator of monocyte chemoattractant protein-1.

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Karimian, Maryam Saberi; Pirro, Matteo; Majeed, Muhammed; Sahebkar, Amirhossein

2017-02-01

Monocyte chemoattractant/chemotactic protein-1 (MCP-1), a member of the CC chemokine family, is one of the key chemokines that regulate migration and tissue infiltration of monocytes/macrophages. Its role in the pathophysiology of several inflammatory diseases has been widely recognized, thus making MCP-1 a possible target for anti-inflammatory treatments. Curcumin (diferuloylmethane) is a natural polyphenol derived from the rhizomes of Curcuma Longa L. (turmeric). Anti-inflammatory action underlies numerous pharmacological effects of curcumin in the control and prevention of several diseases. The purpose of this review is to evaluate the effects of curcumin on the regulation of MCP-1 as a key mediator of chemotaxis and inflammation, and the biological consequences thereof. In vitro studies have shown that curcumin can decrease MCP-1 production in various cell lines. Animal studies have also revealed that curcumin can attenuate MCP-1 expression and improve a range of inflammatory diseases through multiple molecular targets and mechanisms of action. There is limited data from human clinical trials showing the decreasing effect of curcumin on MCP-1 concentrations and improvement of the course of inflammatory diseases. Most of the in vitro and animal studies confirm that curcumin exert its MCP-1-lowering and anti-inflammatory effects by down-regulating the mitogen-activated protein kinase (MAPK) and NF-κB signaling pathway. As yet, there is limited data from human clinical trials showing the effect of curcumin on MCP-1 levels and improvement of the course of inflammatory diseases. More evidence, especially from human studies, is needed to better assess the effects of curcumin on circulating MCP-1 in different human diseases and the role of this modulatory effect in the putative anti-inflammatory properties of curcumin. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effect and possible mechanism of monocyte-derived VEGF on monocyte-endothelial cellular adhesion after electrical burns.

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Ruan, Qiongfang; Zhao, Chaoli; Ye, Ziqing; Ruan, Jingjing; Xie, Qionghui; Xie, Weiguo

2015-06-01

One of the major obstacles in the treatment of severe electrical burns is properly handling the resulting uncontrolled inflammation. Such inflammation often causes secondary injury and necrosis, thus complicating patient outcomes. Vascular endothelial grow factor (VEGF) has emerged as an important mediator for the recruitment of monocytes to the site inflammation. This study was designed to explore the effects and possible mechanism of VEGF on monocyte-endothelial cellular adhesion. To do so, we used a cultured human monocytic cell line (THP-1) that was stimulated with serum derived from rats that had received electrical burns. Serum was obtained from rats that had received electrical burns. Both the VEGF and soluble flt-1 (sflt-1) concentrations of the serum were determined by double-antibody sandwich ELISA. The concentrations of VEGF, sflt-1, and TNF-α obtained from the cell-free cultured supernatant of THP-1 cells that had been exposed to the serum were then determined by double-antibody sandwich ELISA. Serum-stimulated THP-1 cells were added to wells with a monolayer of endothelial cells to detect the level of monocyte-endothelial cells adhesion. Finally, the state of phosphorylation of AKT was determined by Western blotting. Both in vivo and in vitro studies showed that compared to controls, the levels of VEGF were significantly increased after electrical burns. This increased was accompanied by a reduction of sflt-1 levels. Furthermore, the serum of rats that had received electrical burns was able to both activate monocytes to secrete TNF-α and enhance monocyte-endothelial cell adhesion. Treatment with the serum also resulted in an up-regulation of the phosphorylation of AKT, but had no effect on the total levels of AKT. Phosphatidylinositide 3-kinases (PI3K) inhibition decreased the number of THP-1 cells that were adhered to endothelial cells. Finally, sequestering VEGF with sflt-1 was able to reduce the effect on monocyte-endothelial cells adhesion by

Heterogeneity of Bovine Peripheral Blood Monocytes

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Jamal Hussen

2017-12-01

Full Text Available Peripheral blood monocytes of several species can be divided into different subpopulations with distinct phenotypic and functional properties. Herein, we aim at reviewing published work regarding the heterogeneity of the recently characterized bovine monocyte subsets. As the heterogeneity of human blood monocytes was widely studied and reviewed, this work focuses on comparing bovine monocyte subsets with their human counterparts regarding their phenotype, adhesion and migration properties, inflammatory and antimicrobial functions, and their ability to interact with neutrophilic granulocytes. In addition, the differentiation of monocyte subsets into functionally polarized macrophages is discussed. Regarding phenotype and distribution in blood, bovine monocyte subsets share similarities with their human counterparts. However, many functional differences exist between monocyte subsets from the two species. In contrast to their pro-inflammatory functions in human, bovine non-classical monocytes show the lowest phagocytosis and reactive oxygen species generation capacity, an absent ability to produce the pro-inflammatory cytokine IL-1β after inflammasome activation, and do not have a role in the early recruitment of neutrophils into inflamed tissues. Classical and intermediate monocytes of both species also differ in their response toward major monocyte-attracting chemokines (CCL2 and CCL5 and neutrophil degranulation products (DGP in vitro. Such differences between homologous monocyte subsets also extend to the development of monocyte-derived macrophages under the influence of chemokines like CCL5 and neutrophil DGP. Whereas the latter induce the differentiation of M1-polarized macrophages in human, bovine monocyte-derived macrophages develop a mixed M1/M2 macrophage phenotype. Although only a few bovine clinical trials analyzed the correlation between changes in monocyte composition and disease, they suggest that functional differences between

Lipopolysaccharide (LPS) stimulates fresh human monocytes to lyse actinomycin D-treated WEHI-164 target cells via increased secretion of a monokine similar to tumor necrosis factor

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Chen, A.R.; McKinnon, K.P.; Koren, H.S.

1985-01-01

The effects of lipopolysaccharide (LPS) on tumoricidal activity of human monocytes freshly isolated from peripheral blood were studied. Actinomycin D-treated WEHI-164 cells were used as targets because they are NK insensitive and are lysed rapidly by monocytes in 6-hr 51 Cr-release assays. Monocytes exhibited significant spontaneous activity without endotoxin. Monocytes either pretreated for 1 hr with LPS or assayed in the presence of LPS exhibited 100- to 1000-fold increased cytolytic activity. Cytolytic activity was heat labile and trypsin sensitive, and was recovered from Sepharose S-200 columns in a single peak with an apparent m.w. between 25,000 and 40,000. Actinomycin D or cycloheximide treatment of monocytes before the addition of LPS inhibited cytolytic monokine production. Cytolytic monokine activity was practically neutralized by specific rabbit antisera to human tumor necrosis factor (TNF). It was concluded that, although fresh human monocytes exhibit spontaneous tumoricidal activity, LPS is a potent activating agent. Its stimulatory effects depend on new transcription and translation and are mediated by enhanced secretion of a cytolytic monokine similar to TNF

Intermediate Monocytes but Not TIE2-Expressing Monocytes Are a Sensitive Diagnostic Indicator for Colorectal Cancer

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Schauer, Dominic; Starlinger, Patrick; Reiter, Christian; Jahn, Nikolaus; Zajc, Philipp; Buchberger, Elisabeth; Bachleitner-Hofmann, Thomas; Bergmann, Michael; Stift, Anton; Gruenberger, Thomas; Brostjan, Christine

2012-01-01

We have conducted the first study to determine the diagnostic potential of the CD14++CD16+ intermediate monocytes as compared to the pro-angiogenic subset of CD14++CD16+TIE2+ TIE2-expressing monocytes (TEMs) in cancer. These monocyte populations were investigated by flow cytometry in healthy volunteers (N = 32) and in colorectal carcinoma patients with localized (N = 24) or metastatic (N = 37) disease. We further determined blood levels of cytokines associated with monocyte regulation. The results revealed the intermediate monocyte subset to be significantly elevated in colorectal cancer patients and to show the highest frequencies in localized disease. Multivariate regression analysis identified intermediate monocytes as a significant independent variable in cancer prediction. With a cut-off value at 0.37% (intermediate monocytes of total leukocytes) the diagnostic sensitivity and specificity ranged at 69% and 81%, respectively. In contrast, TEM levels were elevated in localized cancer but did not differ significantly between groups and none of the cytokines correlated with monocyte subpopulations. Of interest, in vitro analyses supported the observation that intermediate monocytes were more potently induced by primary as opposed to metastatic cancer cells which may relate to the immunosuppressive milieu established in the advanced stage of metastatic disease. In conclusion, intermediate monocytes as compared to TIE2-expressing monocytes are a more sensitive diagnostic indicator of colorectal cancer. PMID:22973451

Intermediate monocytes but not TIE2-expressing monocytes are a sensitive diagnostic indicator for colorectal cancer.

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Dominic Schauer

Full Text Available We have conducted the first study to determine the diagnostic potential of the CD14++CD16+ intermediate monocytes as compared to the pro-angiogenic subset of CD14++CD16+TIE2+ TIE2-expressing monocytes (TEMs in cancer. These monocyte populations were investigated by flow cytometry in healthy volunteers (N = 32 and in colorectal carcinoma patients with localized (N = 24 or metastatic (N = 37 disease. We further determined blood levels of cytokines associated with monocyte regulation. The results revealed the intermediate monocyte subset to be significantly elevated in colorectal cancer patients and to show the highest frequencies in localized disease. Multivariate regression analysis identified intermediate monocytes as a significant independent variable in cancer prediction. With a cut-off value at 0.37% (intermediate monocytes of total leukocytes the diagnostic sensitivity and specificity ranged at 69% and 81%, respectively. In contrast, TEM levels were elevated in localized cancer but did not differ significantly between groups and none of the cytokines correlated with monocyte subpopulations. Of interest, in vitro analyses supported the observation that intermediate monocytes were more potently induced by primary as opposed to metastatic cancer cells which may relate to the immunosuppressive milieu established in the advanced stage of metastatic disease. In conclusion, intermediate monocytes as compared to TIE2-expressing monocytes are a more sensitive diagnostic indicator of colorectal cancer.

M1 and M2 Monocytes in Rheumatoid Arthritis: A Contribution of Imbalance of M1/M2 Monocytes to Osteoclastogenesis

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Shoichi Fukui

2018-01-01

Full Text Available ObjectivesWe investigated the relationships among M1 monocytes, M2 monocytes, osteoclast (OC differentiation ability, and clinical characteristics in patients with rheumatoid arthritis (RA.MethodsPeripheral blood mononuclear cells (PBMCs were isolated from RA patients and healthy donors, and we then investigated the number of M1 monocytes or M2 monocytes by fluorescence-activated cell sorting. We also obtained and cultured CD14-positive cells from PBMCs from RA patients and healthy donors to investigate OC differentiation in vitro.ResultsForty RA patients and 20 healthy donors were included. Twenty-two patients (55% were anticitrullinated protein antibody (ACPA positive. The median M1/M2 ratio was 0.59 (0.31–1.11, interquartile range. There were no significant differences between the RA patients and healthy donors. There was a positive correlation between the M1/M2 ratio and the differentiated OC number in vitro in RA patients (ρ = 0.81, p < 0.001. The ACPA-positive patients had significantly higher M1/M2 ratios in vivo (p = 0.028 and significantly greater numbers of OCs in vitro (p = 0.005 than the ACPA-negative patients. Multivariable regression analysis revealed that the M1/M2 ratio was the sole significant contribution factor to in vitro osteoclastogenesis. RA patients with M1/M2 ratios >1 (having relatively more M1 monocytes had higher C-reactive protein and erythrocyte sedimentation rates than RA patients with M1/M2 ratios ≤1. M1-dominant monocytes in vitro produced higher concentrations of interleukin-6 upon stimulation with lipopolysaccharide than M2 monocytes.ConclusionM1/M2 monocytes imbalance strongly contributes to osteoclastogenesis of RA patients. Our findings cast M1 and M2 monocyte subsets in a new light as a new target of treatments for RA to prevent progression of osteoclastic bone destruction.

STAT3 activation in monocytes accelerates liver cancer progression

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Wu, Wen-Yong; Li, Jun; Wu, Zheng-Sheng; Zhang, Chang-Le; Meng, Xiang-Ling

2011-01-01

Signal transducer and activator of transcription 3 (STAT3) is an important transcription factor ubiquitously expressed in different cell types. STAT3 plays an essential role in cell survival, proliferation, and differentiation. Aberrantly hyper-activated STAT3 signaling in cancer cells and in the tumor microenvironment has been detected in a wide variety of human cancers and is considered an important factor for cancer initiation, development, and progression. However, the role of STAT3 activation in monocytes in the development of HCC has not been well understood. Immunohistochemical analysis of phosphorylated STAT3 was performed on tissue microarray from HCC patients. Using a co-culture system in vivo, HCC cell growth was determined by the MTT assay. In vivo experiments were conducted with mice given diethylinitrosamine (DEN), which induces HCC was used to investigate the role of STAT3 expression in monocytes on tumor growth. Real-time PCR was used to determine the expression of cell proliferation and cell arrest associated genes in the tumor and nontumor tissue from liver. Phosphorylated STAT3 was found in human hepatocellular carcinoma tissue samples and was expressed in tumor cells and also in monocytes. Phosphorylated STAT3 expression in monocyte was significantly correlated to advanced clinical stage of HCC and a poor prognosis. Using a co-culture system in vivo, monocytes promoted HCC cell growth via the IL-6/STAT3 signaling pathway. The STAT3 inhibitor, NSC 74859, significantly suppressed tumor growth in vivo in mice with diethylinitrosamine (DEN)-induced HCC. In this animal model, blockade of STAT3 with NSC 74859 induced tumor cell apoptosis, while inhibiting both tumor cells and monocytes proliferation. Furthermore, NSC 74859 treatment suppressed cancer associated inflammation in DEN-induce HCC. Our data suggest constitutively activated STAT3 monocytes promote liver tumorigenesis in clinical patients and animal experiments. Thus, STAT3 in tumor

Platelet-derived growth factor (PDGF-BB-mediated induction of monocyte chemoattractant protein 1 in human astrocytes: implications for HIV-associated neuroinflammation

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Bethel-Brown Crystal

2012-12-01

Full Text Available Abstract Chemokine (C-C motif ligand 2, also known as monocyte chemoattractant protein 1 (MCP-1 is an important factor for the pathogenesis of HIV-associated neurocognitive disorders (HAND. The mechanisms of MCP-1-mediated neuropathogenesis, in part, revolve around its neuroinflammatory role and the recruitment of monocytes into the central nervous system (CNS via the disrupted blood-brain barrier (BBB. We have previously demonstrated that HIV-1/HIV-1 Tat upregulate platelet-derived growth factor (PDGF-BB, a known cerebrovascular permeant; subsequently, the present study was aimed at exploring the regulation of MCP-1 by PDGF-BB in astrocytes with implications in HAND. Specifically, the data herein demonstrate that exposure of human astrocytes to HIV-1 LAI elevated PDGF-B and MCP-1 levels. Furthermore, treating astrocytes with the human recombinant PDGF-BB protein significantly increased the production and release of MCP-1 at both the RNA and protein levels. MCP-1 induction was regulated by activation of extracellular-signal-regulated kinase (ERK1/2, c-Jun N-terminal kinase (JNK and p38 mitogen-activated protein (MAP kinases and phosphatidylinositol 3-kinase (PI3K/Akt pathways and the downstream transcription factor, nuclear factor κB (NFκB. Chromatin immunoprecipitation (ChIP assays demonstrated increased binding of NFκB to the human MCP-1 promoter following PDGF-BB exposure. Conditioned media from PDGF-BB-treated astrocytes increased monocyte transmigration through human brain microvascular endothelial cells (HBMECs, an effect that was blocked by STI-571, a tyrosine kinase inhibitor (PDGF receptor (PDGF-R blocker. PDGF-BB-mediated release of MCP-1 was critical for increased permeability in an in vitro BBB model as evidenced by blocking antibody assays. Since MCP-1 is linked to disease severity, understanding its modulation by PDGF-BB could aid in understanding the proinflammatory responses in HAND. These results suggest that astrocyte

Susceptibility and response of human blood monocyte subsets to primary dengue virus infection.

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Kok Loon Wong

Full Text Available Human blood monocytes play a central role in dengue infections and form the majority of virus infected cells in the blood. Human blood monocytes are heterogeneous and divided into CD16(- and CD16(+ subsets. Monocyte subsets play distinct roles during disease, but it is not currently known if monocyte subsets differentially contribute to dengue protection and pathogenesis. Here, we compared the susceptibility and response of the human CD16(- and CD16(+ blood monocyte subsets to primary dengue virus in vitro. We found that both monocyte subsets were equally susceptible to dengue virus (DENV2 NGC, and capable of supporting the initial production of new infective virus particles. Both monocyte subsets produced anti-viral factors, including IFN-α, CXCL10 and TRAIL. However, CD16(+ monocytes were the major producers of inflammatory cytokines and chemokines in response to dengue virus, including IL-1β, TNF-α, IL-6, CCL2, 3 and 4. The susceptibility of both monocyte subsets to infection was increased after IL-4 treatment, but this increase was more profound for the CD16(+ monocyte subset, particularly at early time points after virus exposure. These findings reveal the differential role that monocyte subsets might play during dengue disease.

The chemokine MCP-1 (CCL2) in the host interaction with cancer: a foe or ally?

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Yoshimura, Teizo

2018-01-29

Macrophages are one of the most abundant leukocyte populations infiltrating tumor tissues and can exhibit both tumoricidal and tumor-promoting activities. In 1989, we reported the purification of monocyte chemoattractant protein-1 (MCP-1) from culture supernatants of mitogen-activated peripheral blood mononuclear cells and tumor cells. MCP-1 is a potent monocyte-attracting chemokine, identical to the previously described lymphocyte-derived chemotactic factor or tumor-derived chemotactic factor, and greatly contributes to the recruitment of blood monocytes into sites of inflammatory responses and tumors. Because in vitro-cultured tumor cells often produce significant amounts of MCP-1, tumor cells are considered to be the main source of MCP-1. However, various non-tumor cells in the tumor stroma also produce MCP-1 in response to stimuli. Studies performed in vitro and in vivo have provided evidence that MCP-1 production in tumors is a consequence of complex interactions between tumor cells and non-tumor cells and that both tumor cells and non-tumor cells contribute to the production of MCP-1. Although MCP-1 production was once considered to be a part of host defense against tumors, it is now believed to regulate the vicious cycle between tumor cells and macrophages that promotes the progression of tumors.Cellular and Molecular Immunology advance online publication, 29 January 2018; doi:10.1038/cmi.2017.135.

Monocyte scintigraphy in rheumatoid arthritis: the dynamics of monocyte migration in immune-mediated inflammatory disease.

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Rogier M Thurlings

2009-11-01

Full Text Available Macrophages are principal drivers of synovial inflammation in rheumatoid arthritis (RA, a prototype immune-mediated inflammatory disease. Conceivably, synovial macrophages are continuously replaced by circulating monocytes in RA. Animal studies from the 1960s suggested that macrophage replacement by monocytes is a slow process in chronic inflammatory lesions. Translation of these data into the human condition has been hampered by the lack of available techniques to analyze monocyte migration in man.We developed a technique that enabled us to analyze the migration of labelled autologous monocytes in RA patients using single photon emission computer tomography (SPECT. We isolated CD14+ monocytes by CliniMACS in 8 patients and labeled these with technetium-99m (99mTc-HMPAO. Monocytes were re-infused into the same patient. Using SPECT we calculated that a very small but specific fraction of 3.4 x 10(-3 (0.95-5.1 x 10(-3 % of re-infused monocytes migrated to the inflamed joints, being detectable within one hour after re-infusion.The results indicate monocytes migrate continuously into the inflamed synovial tissue of RA patients, but at a slow macrophage-replacement rate. This suggests that the rapid decrease in synovial macrophages that occurs after antirheumatic treatment might rather be explained by an alteration in macrophage retention than in monocyte influx and that RA might be particularly sensitive to treatments targeting inflammatory cell retention.

Correlation of urinary monocyte chemo-attractant protein-1 with other parameters of renal injury in type-II diabetes mellitus

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Ibrahim Salwa

2008-01-01

Full Text Available Diabetic nephropathy (DN is the leading cause of end-stage renal disease in the western world. Increased number of interstitial macrophages has been observed in biopsies from patients with DN. Monocyte chemo-attractant protein-1 (MCP-1 is the strongest known chemo-tactic factor for monocytes and is upregulated in DN. We examined urinary levels of MCP-1 in patients with type-2 diabetes mellitus (DM to assess its possible correlation with other para-meters of renal injury. The urinary MCP-1 level was assessed in 75 patients with type-2 DM (25 patients each with no microalbuminuria, with macroalbuminuria and, with renal impairment and compared them with matched healthy control subjects. The HbA1c and estimated glomerular fil-tration rate (eGFR derived from the abbreviated Modification of Diet in Renal Disease (MDRD equation were examined in the study groups in relation to the urinary MCP-1. The urinary MCP-1 level was significantly higher in patients with micro and macroalbuminuria (167.41 ± 50.23 and 630.87 ± 318.10 ng/gm creatinine respectively as compared with normoalbuminuric patients and healthy controls (63.85 ± 21.15 and 61.50 ± 24.81 ng/gm creatinine, p< 0.001. MCP-1 correlated positively with urine albumin/creatinine ratio (ACR (r= 0.75, p< 0.001, HbA1c (r= 0.55, p< 0.001 and inversely with eGFR (r=-0.60, p< 0.001. Our findings suggest that hyperglycemia is associated with increased urinary levels of MCP-1 that is closely linked to renal damage as reflected by proteinuria and eGFR levels. Collectively, these findings suggest that MCP-1 is in-volved in the pathogenesis of diabetic nephropathy through its various stages.

Increased MCP-1 gene expression in monocytes of severe OSA patients and under intermittent hypoxia.

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Chuang, Li-Pang; Chen, Ning-Hung; Lin, Yuling; Ko, Wen-Shan; Pang, Jong-Hwei S

2016-03-01

Obstructive sleep apnea (OSA) is known to be a risk factor of coronary artery disease. Monocyte chemoattractant protein-1 (MCP-1), as a critical factor for monocyte infiltration, is known to play a role in the development of atherosclerosis. This study aimed to investigate the effect of intermittent hypoxia, the hallmark of OSA, on the MCP-1 expression of monocytes. Peripheral blood was sampled from 61 adults enrolled for suspected OSA. RNA was prepared from the isolated monocytes for the analysis of MCP-1. The effect of in vitro intermittent hypoxia on the regulation and function of MCP-1 was investigated on THP-1 monocytic cells and human monocytes. The mRNA and secreted protein levels were investigated by RT/real-time PCR and enzyme-linked immunosorbent assay, respectively. Monocytic MCP-1 gene expression was found to be increased significantly in severe OSA patients. In vitro intermittent hypoxia was demonstrated to increase the mRNA and protein expression levels of MCP-1 dose- and time-dependently in THP-1 monocytic cells. The MCP-1 mRNA expression in monocytes isolated from OSA patient was induced to a much higher level compared to that from normal control. Pre-treatment with inhibitor for p42/44 MAPK or p38 MAPK suppressed the activation of MCP-1 expression by intermittent hypoxia. This is the first study to demonstrate the increase of MCP-1 gene expression in monocytes of severe OSA patients. In addition, monocytic MCP-1 gene expression can be induced under intermittent hypoxia.

The alpha hemolisina of Escherichia Coli induces increases in the calcium citoplasmico of neutrofilos and monocytes human beings

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Garcia, J.

2000-01-01

Escherichia coli alpha hemolysin (AH) and the calcium ionophores ionomycin and 4 Br A23187 caused increases in cell fluorescence, indicative of elevations in cytoplasmic calcium, in fura 2-loaded human polymorphonuclear leukocytes(PMN) and monocytes (MN). The increase in fluorescence caused by AH was dose dependent. Quelation of extracellular calcium with EGTA prevented fluorescence increases in PMN exposed to 2 HU50/ml AH, but did not prevent a small increase in 4 μM, ionomycin-treated PMN, indicating that ionomycin treatment under conditions of calcium quelation can mobilize calcium from internal stores, and that entry of external calcium accounts for most of the increases in cell fluorescence in cells treated with both AH and calcium ionophores. AH, as well as calcium ionophores and the chemotactic peptide FMLP caused rease of myeloperoxidase (MPO) from PMM suggesting that increments in intracellular calcium cause degramulation with release of granule contents (Author) [es

Neutrophil chemotactic activity in bronchoalveolar lavage fluid of patients with AIDS-associated Pneumocystis carinii pneumonia

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Benfield, T L; Kharazmi, A; Larsen, C G

1997-01-01

been shown to confer a poor prognosis in PCP. We therefore investigated the potential of BAL fluid from 17 patients with PCP to induce neutrophil chemotaxis. BAL fluid from patients induced considerable neutrophil chemotactic activity compared to normal controls. Elevated levels of IL-8 were detected...... in patient samples as compared to controls. A specific anti-IL-8 antibody significantly reduced chemotactic activity of patient samples by more than 50%. In conclusion, IL-8 appears to be a significant participant of neutrophil chemotaxis in AIDS-associated PCP, and may participate in the recruitment...

Chemotactic droplet swimmers in complex geometries

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Jin, Chenyu; Hokmabad, Babak V.; Baldwin, Kyle A.; Maass, Corinna C.

2018-02-01

Chemotaxis1 and auto-chemotaxis are key mechanisms in the dynamics of micro-organisms, e.g. in the acquisition of nutrients and in the communication between individuals, influencing the collective behaviour. However, chemical signalling and the natural environment of biological swimmers are generally complex, making them hard to access analytically. We present a well-controlled, tunable artificial model to study chemotaxis and autochemotaxis in complex geometries, using microfluidic assays of self-propelling oil droplets in an aqueous surfactant solution (Herminghaus et al 2014 Soft Matter 10 7008-22 Krüger et al 2016 Phys. Rev. Lett. 117). Droplets propel via interfacial Marangoni stresses powered by micellar solubilisation. Moreover, filled micelles act as a chemical repellent by diffusive phoretic gradient forces. We have studied these chemotactic effects in a series of microfluidic geometries, as published in Jin et al (2017 Proc. Natl Acad. Sci. 114 5089-94): first, droplets are guided along the shortest path through a maze by surfactant diffusing into the maze from the exit. Second, we let auto-chemotactic droplet swimmers pass through bifurcating microfluidic channels and record anticorrelations between the branch choices of consecutive droplets. We present an analytical Langevin model matching the experimental data. In a previously unpublished experiment, pillar arrays of variable sizes and shapes provide a convex wall interacting with the swimmer and, in the case of attachment, bending its trajectory and forcing it to revert to its own trail. We observe different behaviours based on the interplay of wall curvature and negative autochemotaxis, i.e. no attachment for highly curved interfaces, stable trapping at large pillars, and a narrow transition region where negative autochemotaxis makes the swimmers detach after a single orbit.

Mucorales species activation of a serum leukotactic factor.

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Marx, R S; Forsyth, K R; Hentz, S K

1982-01-01

Previous studies have suggested that the focal accumulation of phagocytic leukocytes is an important feature of the host response in mucormycosis. To ascertain the basis for this influx of inflammatory cells, we evaluated the effect of members of the order Mucorales, including species from the genera Rhizopus, Absidia, and Mucor, on the chemotactic activity of normal human serum for neutrophils and monocytes. Both hyphae and spores produced concentration-dependent chemotaxigenesis in serum to a maximum level equivalent to that produced by zymosan activation of serum. Chemotactic activity was similar for live and heat-killed hyphae. No leukotactic activity was demonstrated in the absence of serum. The pretreatment of serum with anti-C3 antibody, heating at 56 degrees C, or 0.01 M EDTA abolished the activity. The pretreatment of serum with 0.01 M ethylene glycol-bis(beta-aminoethyl ether)-N,N-tetraacetic acid did not abolish the activity. These data provide evidence that the leukotactic activity of Mucorales species is generated through the alternative complement pathway. PMID:6759409

Sialoadhesin expressed on IFN-induced monocytes binds HIV-1 and enhances infectivity.

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Hans Rempel

2008-04-01

Full Text Available HIV-1 infection dysregulates the immune system and alters gene expression in circulating monocytes. Differential gene expression analysis of CD14(+ monocytes from subjects infected with HIV-1 revealed increased expression of sialoadhesin (Sn, CD169, Siglec 1, a cell adhesion molecule first described in a subset of macrophages activated in chronic inflammatory diseases.We analyzed sialoadhesin expression on CD14(+ monocytes by flow cytometry and found significantly higher expression in subjects with elevated viral loads compared to subjects with undetectable viral loads. In cultured CD14(+ monocytes isolated from healthy individuals, sialoadhesin expression was induced by interferon-alpha and interferon-gamma but not tumor necrosis factor-alpha. Using a stringent binding assay, sialoadhesin-expressing monocytes adsorbed HIV-1 through interaction with the sialic acid residues on the viral envelope glycoprotein gp120. Furthermore, monocytes expressing sialoadhesin facilitated HIV-1 trans infection of permissive cells, which occurred in the absence of monocyte self-infection.Increased sialoadhesin expression on CD14(+ monocytes occurred in response to HIV-1 infection with maximum expression associated with high viral load. We show that interferons induce sialoadhesin in primary CD14(+ monocytes, which is consistent with an antiviral response during viremia. Our findings suggest that circulating sialoadhesin-expressing monocytes are capable of binding HIV-1 and effectively delivering virus to target cells thereby enhancing the distribution of HIV-1. Sialoadhesin could disseminate HIV-1 to viral reservoirs during monocyte immunosurveillance or migration to sites of inflammation and then facilitate HIV-1 infection of permissive cells.

EMMPRIN (CD147/basigin) mediates platelet-monocyte interactions in vivo and augments monocyte recruitment to the vascular wall.

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Schulz, C; von Brühl, M-L; Barocke, V; Cullen, P; Mayer, K; Okrojek, R; Steinhart, A; Ahmad, Z; Kremmer, E; Nieswandt, B; Frampton, J; Massberg, S; Schmidt, R

2011-05-01

Platelets play a central role in hemostasis, in inflammatory diseases such as atherosclerosis, and during thrombus formation following vascular injury. Thereby, platelets interact intensively with monocytes and enhance their recruitment to the vascular wall. To investigate the role of the extracellular matrix metalloproteinase inducer (EMMPRIN) in platelet-monocyte interactions. Isolated human monocytes were perfused in vitro over firmly adherent platelets to allow investigation of the role of EMMPRIN in platelet-monocyte interactions under flow conditions. Monocytes readily bound to surface-adherent platelets. Both antibody blockade and gene silencing of monocyte EMMPRIN substantially attenuated firm adhesion of monocytes to platelets at arterial and venous shear rates. In vivo, platelet interactions with the murine monocyte cell line ANA-1 were significantly decreased when ANA-1 cells were pretreated with EMMPRIN-silencing small interfering RNA prior to injection into wild-type mice. Using intravital microscopy, we showed that recruitment of EMMPRIN-silenced ANA-1 to the injured carotid artery was significantly reduced as compared with control cells. Further silencing of EMMPRIN resulted in significantly fewer ANA-1-platelet aggregates in the mouse circulation as determined by flow cytometry. Finally, we identified glycoprotein (GP)VI as a critical corresponding receptor on platelets that mediates interaction with monocyte EMMPRIN. Thus, blocking of GPVI inhibited the effect of EMMPRIN on firm monocyte adhesion to platelets under arterial flow conditions in vitro, and abrogated EMMPRIN-mediated platelet-monocyte aggregate formation in vivo. EMMPRIN supports platelet-monocyte interactions and promotes monocyte recruitment to the arterial wall. Therefore, EMMPRIN might represent a novel target to reduce vascular inflammation and atherosclerotic lesion development. © 2011 International Society on Thrombosis and Haemostasis.

Palmitate and insulin synergistically induce IL-6 expression in human monocytes

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Lumpkin Charles K

2010-11-01

Full Text Available Abstract Background Insulin resistance is associated with a proinflammatory state that promotes the development of complications such as type 2 diabetes mellitus (T2DM and atherosclerosis. The metabolic stimuli that initiate and propagate proinflammatory cytokine production and the cellular origin of proinflammatory cytokines in insulin resistance have not been fully elucidated. Circulating proinflammatory monocytes show signs of enhanced inflammation in obese, insulin resistant subjects and are thus a potential source of proinflammatory cytokine production. The specific, circulating metabolic factors that might stimulate monocyte inflammation in insulin resistant subjects are poorly characterized. We have examined whether saturated nonesterified fatty acids (NEFA and insulin, which increase in concentration with developing insulin resistance, can trigger the production of interleukin (IL-6 and tumor necrosis factor (TNF-α in human monocytes. Methods Messenger RNA and protein levels of the proinflammatory cytokines IL-6 and TNF-α were measured by quantitative real-time PCR (qRT-PCR and Luminex bioassays. Student's t-test was used with a significance level of p Results Esterification of palmitate with coenzyme A (CoA was necessary, while β-oxidation and ceramide biosynthesis were not required, for the induction of IL-6 and TNF-α in THP-1 monocytes. Monocytes incubated with insulin and palmitate together produced more IL-6 mRNA and protein, and more TNF-α protein, compared to monocytes incubated with palmitate alone. Incubation of monocytes with insulin alone did not affect the production of IL-6 or TNF-α. Both PI3K-Akt and MEK/ERK signalling pathways are important for cytokine induction by palmitate. MEK/ERK signalling is necessary for synergistic induction of IL-6 by palmitate and insulin. Conclusions High levels of saturated NEFA, such as palmitate, when combined with hyperinsulinemia, may activate human monocytes to produce

Monocytic myeloid-derived suppressor cells as prognostic factor in chronic myeloid leukaemia patients treated with dasatinib.

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Giallongo, Cesarina; Parrinello, Nunziatina L; La Cava, Piera; Camiolo, Giuseppina; Romano, Alessandra; Scalia, Marina; Stagno, Fabio; Palumbo, Giuseppe A; Avola, Roberto; Li Volti, Giovanni; Tibullo, Daniele; Di Raimondo, Francesco

2018-02-01

Myeloid suppressor cells are a heterogeneous group of myeloid cells that are increased in patients with chronic myeloid leukaemia (CML) inducing T cell tolerance. In this study, we found that therapy with tyrosine kinase inhibitors (TKI) decreased the percentage of granulocytic MDSC, but only patients treated with dasatinib showed a significant reduction in the monocytic subset (M-MDSC). Moreover, a positive correlation was observed between number of persistent M-MDSC and the value of major molecular response in dasatinib-treated patients. Serum and exosomes from patients with CML induced conversion of monocytes from healthy volunteers into immunosuppressive M-MDSC, suggesting a bidirectional crosstalk between CML cells and MDSC. Overall, we identified M-MDSC as prognostic factors in patients treated with dasatinib. It might be of interest to understand whether MDSC may be a candidate predictive markers of relapse risk following TKI discontinuation, suggesting their potential significance as practice of precision medicine. © 2017 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

Monocyte functions in diabetes mellitus

DEFF Research Database (Denmark)

Geisler, C; Almdal, T; Bennedsen, J

1982-01-01

The aim of this study was to investigate the functions of monocytes obtained from 14 patients with diabetes mellitus (DM) compared with those of monocytes from healthy individuals. It was found that the total number of circulating monocytes in the 14 diabetic patients was lower than that from...... for the elucidation of concomitant infections in diabetic patients are discussed....

Transverse Chemotactic Migration of Bacteria from High to Low Permeability Regions in a Dual Permeability Porous Microfluidic Device

Science.gov (United States)

Singh, R.; Olson, M. S.

2011-12-01

Low permeability regions sandwiched between high permeability regions such as clay lenses are difficult to treat using conventional treatment methods. Trace concentrations of contaminants such as non-aqueous phase liquids (NAPLs) remain trapped in these regions and over the time diffuse out into surrounding water thereby acting as a long term source of groundwater contamination. Bacterial chemotaxis (directed migration toward a contaminant source), may be helpful in enhancing bioremediation of such contaminated sites. This study is focused on simulating a two-dimensional dual-permeability groundwater contamination scenario using microfluidic devices and evaluating transverse chemotactic migration of bacteria from high to low permeability regions. A novel bi-layer polydimethylsiloxane (PDMS) microfluidic device was fabricated using photolithography and soft lithography techniques to simulate contamination of a dual- permeability region due to leakage from an underground storage tank into a low permeability region. This device consists of a porous channel through which a bacterial suspension (Escherchia Coli HCB33) is flown and another channel for injecting contaminant/chemo-attractant (DL-aspertic acid) into the porous channel. The pore arrangement in the porous channel contains a 2-D low permeability region surrounded by high permeability regions on both sides. Experiments were performed under chemotactic and non-chemotactic (replacing attractant with buffer solution in the non porous channel) conditions. Images were captured in transverse pore throats at cross-sections 4.9, 9.8, and 19.6 mm downstream from the attractant injection point and bacteria were enumerated in the middle of each pore throat. Bacterial chemotaxis was quantified in terms of the change in relative bacterial counts in each pore throat at cross-sections 9.8 and 19.6 mm with respect to counts at the cross-section at 4.9 mm. Under non-chemotactic conditions, relative bacterial count was observed

Effect of cigarette smoke on monocyte procoagulant activity: Focus on platelet-derived brain-derived neurotrophic factor (BDNF).

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Amadio, Patrizia; Baldassarre, Damiano; Sandrini, Leonardo; Weksler, Babette B; Tremoli, Elena; Barbieri, Silvia S

2017-01-01

Cigarette smoke (CS) activates platelets, promotes vascular dysfunction, and enhances Tissue Factor (TF) expression in blood monocytes favoring pro-thrombotic states. Brain-derived neurotrophic factor (BDNF), a member of the family of neurotrophins involved in survival, growth, and maturation of neurons, is released by activated platelets (APLTs) and plays a role in the cardiovascular system. The effect of CS on circulating levels of BDNF is controversial and the function of circulating BDNF in atherothrombosis is not fully understood. Here, we have shown that human platelets, treated with an aqueous extract of CS (CSE), released BDNF in a dose-dependent manner. In addition, incubation of human monocytes with BDNF or with the supernatant of platelets activated with CSE increased TF activity by a Tropomyosin receptor kinase B (TrkB)-dependent mechanism. Finally, comparing serum and plasma samples of 12 male never smokers (NS) and 29 male active smokers (AS) we observed a significant increase in microparticle-associated TF activity (MP-TF) as well as BDNF in AS, while in serum, BDNF behaved oppositely. Taken together these findings suggest that platelet-derived BDNF is involved in the regulation of TF activity and that CS plays a role in this pathway by favoring a pro-atherothrombotic state.

Radiation effects on cultured human monocytes and on monocyte-derived macrophages

International Nuclear Information System (INIS)

Buescher, E.S.; Gallin, J.I.

1984-01-01

Prior to administration, leukocyte transfusions are commonly irradiated with up to 5,000 R to eliminate lymphocytes and thereby prevent graft-versus-host disease in the recipient. It has been widely believed that phagocytes are resistant to this irradiation. In a recent report, it was noted that phagocyte oxidative metabolism was compromised during preparation of white cells for transfusion. As part of the effort to examine the basis for this inhibition of phagocyte function during white cell preparation, an assessment was made of the effects of irradiation on the long-lived monocytes that have been shown to persist at inflammatory foci posttransfusion. Human monocytes were irradiated for up to 3 min, receiving 2,500-5,000 R. This irradiation damaged human monocytes, significantly decreasing their in vitro survival for the first 3 wk of culture, and growth as assessed by two-dimensional cell size measurements during the first 2 wk of culture. Despite smaller cell size, total cell protein was significantly increased over time in irradiated cultures. Extracellular release of lysozyme and beta-glucuronidase per cell was not affected by irradiation, but extracellular lactate dehydrogenase (LDH) release was significantly increased after irradiation. Irradiated monocytes killed Listeria monocytogenes at a slower rate than the nonirradiated controls. Thus, the data indicate that irradiation in doses used to prevent graft-versus-host disease in leukocyte transfusion recipients has a deleterious effect on in vitro human monocyte survival and function

Beneifcial effect of reifned red palm oil on lipid peroxidation and monocyte tissue factor in HCV-related liver disease：a randomized controlled study

Institute of Scientific and Technical Information of China (English)

Roberto Catanzaro; Nicola Zerbinati; Umberto Solimene; Massimiliano Marcellino; Dheeraj Mohania; Angelo Italia; Antonio Ayala; Francesco Marotta

2016-01-01

BACKGROUND: A large amount of endotoxin can be detected in the peripheral venous blood of patients with liver cirrhosis, contributing to the pathogenesis of hepatotoxicity because of its role in oxidative stress. The present study aimed to test the effect of the supplementation with red palm oil (RPO), which is a natural oil obtained from oil palm fruit (Elaeis guineensis) rich in natural fat-soluble tocopherols, tocotrienols and carot-enoids, on lipid peroxidation and endotoxemia with plasma endotoxin-inactivating capacity, proinlfammatory cytokines proifle, and monocyte tissue factor in patients with chronic liver disease. METHODS: The study group consisted of sixty patients (34 males and 26 females; mean age 62 years, range 54-75) with Child A/B, genotype 1 HCV-related cirrhosis without a history of ethanol consumption, randomly enrolled into an 8-week oral daily treatment with either vitamin E or RPO. All patients had undergone an upper gastrointestinal endoscopy 8 months before, and 13 out of them showed esophageal varices. RESULTS: Both treatments signiifcantly decreased erythro-cyte malondialdehyde and urinary isoprostane output, only RPO signiifcantly affected macrophage-colony stimulating fac-tor and monocyte tissue factor. Liver ultrasound imaging did not show any change. CONCLUSIONS: RPO beneifcially modulates oxidative stress and, not least, downregulates macrophage/monocyte inlfam-matory parameters. RPO can be safely advised as a valuable nutritional implementation tool in the management of chron-ic liver diseases.

TLR4-mediated expression of Mac-1 in monocytes plays a pivotal role in monocyte adhesion to vascular endothelium.

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Seung Jin Lee

Full Text Available Toll-like receptor 4 (TLR4 is known to mediate monocyte adhesion to endothelial cells, however, its role on the expression of monocyte adhesion molecules is unclear. In the present study, we investigated the role of TLR4 on the expression of monocyte adhesion molecules, and determined the functional role of TLR4-induced adhesion molecules on monocyte adhesion to endothelial cells. When THP-1 monocytes were stimulated with Kdo2-Lipid A (KLA, a specific TLR4 agonist, Mac-1 expression was markedly increased in association with an increased adhesion of monocytes to endothelial cells. These were attenuated by anti-Mac-1 antibody, suggesting a functional role of TLR4-induced Mac-1 on monocyte adhesion to endothelial cells. In monocytes treated with MK886, a 5-lipoxygenase (LO inhibitor, both Mac-1 expression and monocyte adhesion to endothelial cells induced by KLA were markedly attenuated. Moreover, KLA increased the expression of mRNA and protein of 5-LO, suggesting a pivotal role of 5-LO on these processes. In in vivo studies, KLA increased monocyte adhesion to aortic endothelium of wild-type (WT mice, which was attenuated in WT mice treated with anti-Mac-1 antibody as well as in TLR4-deficient mice. Taken together, TLR4-mediated expression of Mac-1 in monocytes plays a pivotal role on monocyte adhesion to vascular endothelium, leading to increased foam cell formation in the development of atherosclerosis.

Age Increases Monocyte Adhesion on Collagen

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Khalaji, Samira; Zondler, Lisa; Kleinjan, Fenneke; Nolte, Ulla; Mulaw, Medhanie A.; Danzer, Karin M.; Weishaupt, Jochen H.; Gottschalk, Kay-E.

2017-05-01

Adhesion of monocytes to micro-injuries on arterial walls is an important early step in the occurrence and development of degenerative atherosclerotic lesions. At these injuries, collagen is exposed to the blood stream. We are interested whether age influences monocyte adhesion to collagen under flow, and hence influences the susceptibility to arteriosclerotic lesions. Therefore, we studied adhesion and rolling of human peripheral blood monocytes from old and young individuals on collagen type I coated surface under shear flow. We find that firm adhesion of monocytes to collagen type I is elevated in old individuals. Pre-stimulation by lipopolysaccharide increases the firm adhesion of monocytes homogeneously in older individuals, but heterogeneously in young individuals. Blocking integrin αx showed that adhesion of monocytes to collagen type I is specific to the main collagen binding integrin αxβ2. Surprisingly, we find no significant age-dependent difference in gene expression of integrin αx or integrin β2. However, if all integrins are activated from the outside, no differences exist between the age groups. Altered integrin activation therefore causes the increased adhesion. Our results show that the basal increase in integrin activation in monocytes from old individuals increases monocyte adhesion to collagen and therefore the risk for arteriosclerotic plaques.

Coordinate viral induction of tumor necrosis factor α and interferon β in human B cells and monocytes

International Nuclear Information System (INIS)

Goldfeld, A.E.; Maniatis, T.

1989-01-01

Human tumor necrosis factor α (TNF-α) gene expression can be induced primarily in cells of the monocyte/macrophage lineage by a variety of inducers, including lipopolysaccharide, phorbol esters such as phorbol 12-myristate 13-acetate, and virus or synthetic double-stranded RNA [poly(I)·poly(C)]. In this paper the authors show that the TNF-α gene also responds to virus and phorbol 12-myristate 13-acetate in B lymphocytes and that virus is the most potent inducer of TNF-α mRNA in both monocyte and B-cell lines. In addition, they show that viral infection coinduces the expression of TNF-α and interferon β mRNA and that viral induction of both genes is blocked by the kinase inhibitor 2-aminopurine. Inhibition of protein synthesis with cycloheximide had no effect on mRNA expression of the genes in one of three cell lines tested (U937) but blocked the viral induction of both genes in another (Namalwa). Thus, the regulatory factors required for mRNA induction of both genes are present prior to the addition of virus in U937 but not in Namalwa cells. However, in a third cell line (JY), cycloheximide blocked viral induction of the interferon β gene but not the TNF-α gene. Taken together, these observations suggest that viral induction of TNF-α and interferon β gene expression may involve overlapping pathways with both common and distinct regulatory factors

Role of CC chemokines (macrophage inflammatory protein-1 beta, monocyte chemoattractant protein-1, RANTES) in acute lung injury in rats

DEFF Research Database (Denmark)

Bless, N M; Huber-Lang, M; Guo, R F

2000-01-01

The role of the CC chemokines, macrophage inflammatory protein-1 beta (MIP-1 beta), monocyte chemotactic peptide-1 (MCP-1), and RANTES, in acute lung inflammatory injury induced by intrapulmonary deposition of IgG immune complexes injury in rats was determined. Rat MIP-1 beta, MCP-1, and RANTES...... were cloned, the proteins were expressed, and neutralizing Abs were developed. mRNA and protein expression for MIP-1 beta and MCP-1 were up-regulated during the inflammatory response, while mRNA and protein expression for RANTES were constitutive and unchanged during the inflammatory response....... Treatment of rats with anti-MIP-1 beta Ab significantly decreased vascular permeability by 37% (p = 0.012), reduced neutrophil recruitment into lung by 65% (p = 0.047), and suppressed levels of TNF-alpha in bronchoalveolar lavage fluids by 61% (p = 0.008). Treatment of rats with anti-rat MCP-1 or anti...

Vascular endothelial growth factor (VEGF), produced by feline infectious peritonitis (FIP) virus-infected monocytes and macrophages, induces vascular permeability and effusion in cats with FIP.

Science.gov (United States)

Takano, Tomomi; Ohyama, Taku; Kokumoto, Aiko; Satoh, Ryoichi; Hohdatsu, Tsutomu

2011-06-01

Feline infectious peritonitis virus (FIPV) causes a fatal disease called FIP in Felidae. The effusion in body cavity is commonly associated with FIP. However, the exact mechanism of accumulation of effusion remains unclear. We investigated vascular endothelial growth factor (VEGF) to examine the relationship between VEGF levels and the amounts of effusion in cats with FIP. Furthermore, we examined VEGF production in FIPV-infected monocytes/macrophages, and we used feline vascular endothelial cells to examine vascular permeability induced by the culture supernatant of FIPV-infected macrophages. In cats with FIP, the production of effusion was related with increasing plasma VEGF levels. In FIPV-infected monocytes/macrophages, the production of VEGF was associated with proliferation of virus. Furthermore, the culture supernatant of FIPV-infected macrophages induced hyperpermeability of feline vascular endothelial cells. It was suggested that vascular permeability factors, including VEGF, produced by FIPV-infected monocytes/macrophages might increase the vascular permeability and the amounts of effusion in cats with FIP. Copyright © 2011 Elsevier B.V. All rights reserved.

Free hemoglobin enhances tumor necrosis factor-alpha production in isolated human monocytes.

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Carrillo, Eddy H; Gordon, Laura E; Richardson, J David; Polk, Hiram C

2002-03-01

A systemic inflammatory response (SIR) is seen in approximately 75% of patients with complex blunt liver injuries treated nonoperatively. Many feel this response is caused by blood, bile, and necrotic tissue accumulation in the peritoneal cavity. Our current treatment for these patients is a delayed laparoscopic washout of the peritoneal cavity, resulting in a dramatic resolution of the SIR. Spectrophotometric analysis of the intraperitoneal fluid has confirmed the presence of high concentrations of free hemoglobin (Hb). We hypothesize that free Hb enhances the local peritoneal response by increasing tumor necrosis factor-alpha (TNF-alpha) production by monocytes, contributing to the local inflammatory response and SIR. Monocytes from five healthy volunteers were isolated and cultured in RPMI-1640 for 24 hours. Treatment groups included saline controls, lipopolysaccharide ([LPS], 10 ng/mL, from Escherichia coli), human Hb (25 microg/mL), and Hb + LPS. Supernatants were analyzed by enzyme-linked immunosorbent assay. Student's t test with Mann-Whitney posttest was used for statistical analysis with p < or = 0.05 considered significant. Free Hb significantly increased TNF-alpha production 915 +/- 223 pg/mL versus saline (p = 0.02). LPS and Hb + LPS further increased TNF-alpha production (2294 pg/mL and 2501 pg/mL, respectively, p < 0.001) compared with saline controls. These data confirm that free Hb is a proinflammatory mediator resulting in the production of significant amounts of TNF-alpha. These in vitro findings support our clinical data in which timely removal of intraperitoneal free hemoglobin helps prevent its deleterious local and systemic inflammatory effects in patients with complex liver injuries managed nonoperatively.

Protective role of klotho protein on epithelial cells upon co-culture with activated or senescent monocytes

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Mytych, Jennifer, E-mail: jennifermytych@gmail.com [Institute of Applied Biotechnology and Basic Sciences, University of Rzeszow, Werynia 502, 36-100 Kolbuszowa (Poland); Centre of Applied Biotechnology and Basic Sciences, University of Rzeszow, Werynia 502, 36-100 Kolbuszowa (Poland); Wos, Izabela; Solek, Przemyslaw; Koziorowski, Marek [Institute of Applied Biotechnology and Basic Sciences, University of Rzeszow, Werynia 502, 36-100 Kolbuszowa (Poland); Centre of Applied Biotechnology and Basic Sciences, University of Rzeszow, Werynia 502, 36-100 Kolbuszowa (Poland)

2017-01-15

Monocytes ensure proper functioning and maintenance of epithelial cells, while good condition of monocytes is a key factor of these interactions. Although, it was shown that in some circumstances, a population of altered monocytes may appear, there is no data regarding their effect on epithelial cells. In this study, using direct co-culture model with LPS-activated and Dox-induced senescent THP-1 monocytes, we reported for the first time ROS-induced DNA damage, reduced metabolic activity, proliferation inhibition and cell cycle arrest followed by p16-, p21- and p27-mediated DNA damage response pathways activation, premature senescence and apoptosis induction in HeLa cells. Also, we show that klotho protein possessing anti-aging and anti-inflammatory characteristics reduced cytotoxic and genotoxic events by inhibition of insulin/IGF-IR and downregulation of TRF1 and TRF2 proteins. Therefore, klotho protein could be considered as a protective factor against changes caused by altered monocytes in epithelial cells. - Highlights: • Activated and senescent THP-1 monocytes induced cyto- and genotoxicity in HeLa cells. • Altered monocytes provoked oxidative and nitrosative stress-induced DNA damage. • DNA damage activated DDR pathways and lead to premature senescence and apoptosis. • Klotho reduced ROS/RNS-mediated toxicity through insulin/IGF-IR pathway inhibition. • Klotho protects HeLa cells from cyto- and genotoxicity induced by altered monocytes.

Protective role of klotho protein on epithelial cells upon co-culture with activated or senescent monocytes

International Nuclear Information System (INIS)

Mytych, Jennifer; Wos, Izabela; Solek, Przemyslaw; Koziorowski, Marek

2017-01-01

Monocytes ensure proper functioning and maintenance of epithelial cells, while good condition of monocytes is a key factor of these interactions. Although, it was shown that in some circumstances, a population of altered monocytes may appear, there is no data regarding their effect on epithelial cells. In this study, using direct co-culture model with LPS-activated and Dox-induced senescent THP-1 monocytes, we reported for the first time ROS-induced DNA damage, reduced metabolic activity, proliferation inhibition and cell cycle arrest followed by p16-, p21- and p27-mediated DNA damage response pathways activation, premature senescence and apoptosis induction in HeLa cells. Also, we show that klotho protein possessing anti-aging and anti-inflammatory characteristics reduced cytotoxic and genotoxic events by inhibition of insulin/IGF-IR and downregulation of TRF1 and TRF2 proteins. Therefore, klotho protein could be considered as a protective factor against changes caused by altered monocytes in epithelial cells. - Highlights: • Activated and senescent THP-1 monocytes induced cyto- and genotoxicity in HeLa cells. • Altered monocytes provoked oxidative and nitrosative stress-induced DNA damage. • DNA damage activated DDR pathways and lead to premature senescence and apoptosis. • Klotho reduced ROS/RNS-mediated toxicity through insulin/IGF-IR pathway inhibition. • Klotho protects HeLa cells from cyto- and genotoxicity induced by altered monocytes.

Galectin-2 induces a proinflammatory, anti-arteriogenic phenotype in monocytes and macrophages.

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Cansu Yıldırım

Full Text Available Galectin-2 is a monocyte-expressed carbohydrate-binding lectin, for which increased expression is genetically determined and associated with decreased collateral arteriogenesis in obstructive coronary artery disease patients. The inhibiting effect of galectin-2 on arteriogenesis was confirmed in vivo, but the mechanism is largely unknown. In this study we aimed to explore the effects of galectin-2 on monocyte/macrophage phenotype in vitro and vivo, and to identify the receptor by which galectin-2 exerts these effects. We now show that the binding of galectin-2 to different circulating human monocyte subsets is dependent on monocyte surface expression levels of CD14. The high affinity binding is blocked by an anti-CD14 antibody but not by carbohydrates, indicating a specific protein-protein interaction. Galectin-2 binding to human monocytes modulated their transcriptome by inducing proinflammatory cytokines and inhibiting pro-arteriogenic factors, while attenuating monocyte migration. Using specific knock-out mice, we show that galectin-2 acts through the CD14/toll-like receptor (TLR-4 pathway. Furthermore, galectin-2 skews human macrophages to a M1-like proinflammatory phenotype, characterized by a reduced motility and expression of an anti-arteriogenic cytokine/growth factor repertoire. This is accompanied by a switch in surface protein expression to CD40-high and CD206-low (M1. In a murine model we show that galectin-2 administration, known to attenuate arteriogenesis, leads to increased numbers of CD40-positive (M1 and reduced numbers of CD206-positive (M2 macrophages surrounding actively remodeling collateral arteries. In conclusion galectin-2 is the first endogenous CD14/TLR4 ligand that induces a proinflammatory, non-arteriogenic phenotype in monocytes/macrophages. Interference with CD14-Galectin-2 interaction may provide a new intervention strategy to stimulate growth of collateral arteries in genetically compromised cardiovascular

Kaempferol impedes IL-32-induced monocyte-macrophage differentiation.

Science.gov (United States)

Nam, Sun-Young; Jeong, Hyun-Ja; Kim, Hyung-Min

2017-08-25

Kaempferol possesses a wide range of therapeutic properties, including antioxidant, anti-inflammatory, and anticancer properties. The present study sought to evaluate the effects and possible pharmacological mechanisms of kaempferol on interleukin (IL)-32-induced monocyte-macrophage differentiation. In this study, we performed flow cytometry assay, immunocytochemical staining, quantitative real-time PCR, enzyme-linked immuno sorbent assay, caspase-1 assay, and Western blotting to observe the effects and underlying mechanisms of kaempferol using the human monocyte cell line THP-1. The flow cytometry, immunocytochemical staining, and real-time PCR results show that kaempferol attenuated IL-32-induced monocyte differentiation to product macrophage-like cells. Kaempferol decreased the production and mRNA expression of pro-inflammatory cytokines, in this case thymic stromal lymphopoietin (TSLP), IL-1β, tumor necrosis factor (TNF)-α, and IL-8. Furthermore, kaempferol inhibited the IL-32-induced activation of p38 and nuclear factor-κB in a dose-dependent manner in THP-1 cells. Kaempferol also ameliorated the lipopolysaccharide-induced production of the inflammatory mediators TSLP, IL-1β, TNF-α, IL-8, and nitric oxide of macrophage-like cells differentiated by IL-32. In brief, our findings may provide new mechanistic insights into the anti-inflammatory effects of kaempferol. Copyright © 2017 Elsevier B.V. All rights reserved.

Elevated levels of homocysteine increase IL-6 production in monocytic Mono Mac 6 cells

NARCIS (Netherlands)

van Aken, B. E.; Jansen, J.; van Deventer, S. J.; Reitsma, P. H.

2000-01-01

Hyperhomocysteinemia is a risk factor for atherosclerosis and thrombosis. The aim of this study was to analyze if exposure of monocytic cells to increased levels of homocysteine (HCY) induces the accumulation of inflammatory mediators. Interleukin (IL)-6 production by monocytic cell line Mono Mac 6

Monocytes with angiogenic potential are selectively induced by liver resection and accumulate near the site of liver regeneration.

Science.gov (United States)

Schauer, Dominic; Starlinger, Patrick; Zajc, Philipp; Alidzanovic, Lejla; Maier, Thomas; Buchberger, Elisabeth; Pop, Lorand; Gruenberger, Birgit; Gruenberger, Thomas; Brostjan, Christine

2014-10-30

Monocytes reportedly contribute to liver regeneration. Three subsets have been identified to date: classical, intermediate, non-classical monocytes. The intermediate population and a subtype expressing TIE2 (TEMs) were suggested to promote angiogenesis. In a clinical setting, we investigated which monocyte subsets are regulated after liver resection and correlate with postoperative liver function. In 38 patients monocyte subsets were evaluated in blood and subhepatic wound fluid by flow cytometry before and 1-3 days after resection of colorectal liver metastases. The monocyte-regulating cytokines macrophage colony stimulating factor (M-CSF), transforming growth factor beta 1 (TGFβ1), and angiopoietin 2 (ANG-2) were measured in patient plasma by ELISA. C-reactive protein (CRP) and liver function parameters were retrieved from routine hospital analyses. On post-operative day (POD) 1 blood monocytes shifted to significantly elevated levels of intermediate monocytes. In wound fluid, a delayed surge in intermediate monocytes was detected by POD 3. Furthermore, TEMs were highly enriched in wound fluid as compared to circulation. CRP and M-CSF levels were substantially increased in patient blood after surgery and correlated significantly with the frequency of intermediate monocytes. In addition, liver function parameters showed a significant association with intermediate monocyte levels on POD 3. The reportedly pro-angiogenic subsets of monocytes are selectively increased upon liver resection and accumulate next to the site of liver regeneration. As previously proposed by in vitro experiments, the release of CRP and M-CSF may trigger the induction of intermediate monocytes. The correlation with liver parameters points to a functional involvement of these monocyte populations in liver regeneration which warrants further investigation.

Ursodeoxycholic acid inhibits TNFα-induced IL-8 release from monocytes.

Science.gov (United States)

O'Dwyer, Aoife M; Lajczak, Natalia K; Keyes, Jennifer A; Ward, Joseph B; Greene, Catherine M; Keely, Stephen J

2016-08-01

Monocytes are critical to the pathogenesis of inflammatory bowel disease (IBD) as they infiltrate the mucosa and release cytokines that drive the inflammatory response. Ursodeoxycholic acid (UDCA), a naturally occurring bile acid with anti-inflammatory actions, has been proposed as a potential new therapy for IBD. However, its effects on monocyte function are not yet known. Primary monocytes from healthy volunteers or cultured U937 monocytes were treated with either the proinflammatory cytokine, TNFα (5 ng/ml) or the bacterial endotoxin, lipopolysaccharide (LPS; 1 μg/ml) for 24 h, in the absence or presence of UDCA (25-100 μM). IL-8 release into the supernatant was measured by ELISA. mRNA levels were quantified by qPCR and changes in cell signaling proteins were determined by Western blotting. Toxicity was assessed by measuring lactate dehydrogenase (LDH) release. UDCA treatment significantly attenuated TNFα-, but not LPS-driven, release of IL-8 from both primary and cultured monocytes. UDCA inhibition of TNFα-driven responses was associated with reduced IL-8 mRNA expression. Both TNFα and LPS stimulated NFκB activation in monocytes, while IL-8 release in response to both cytokines was attenuated by an NFκB inhibitor, BMS-345541. Interestingly, UDCA inhibited TNFα-, but not LPS-stimulated, NFκB activation. Finally, TNFα, but not LPS, induced phosphorylation of TNF receptor associated factor (TRAF2), while UDCA cotreatment attenuated this response. We conclude that UDCA specifically inhibits TNFα-induced IL-8 release from monocytes by inhibiting TRAF2 activation. Since such actions would serve to dampen mucosal immune responses in vivo, our data support the therapeutic potential of UDCA for IBD. Copyright © 2016 the American Physiological Society.

Tolerance of monocytes and macrophages in response to bacterial endotoxin

Directory of Open Access Journals (Sweden)

Ewelina Wiśnik

2017-03-01

Full Text Available Monocytes belong to myeloid effector cells, which constitute the first line of defense against pathogens, also called the nonspecific immune system and play an important role in the maintenance of tissue homeostasis. In response to stimulation, monocytes differentiate into macrophages capable of microorganism phagocytosis and secrete factors that play a key role in the regulation of immune responses. However excessive exposure of monocytes/macrophages to the lipopolysaccharide (LPS of Gram negative bacteria leads to the acquisition of immune tolerance by these cells. Such state results from disruption of different biological processes, for example intracellular signaling pathways and is accompanied by a number of disease states (immune, inflammatory or neoplastic conditions. Regulation of monocytes/macrophages activity is controlled by miRNAs, which are involved in the modulation of immune tolerance acquired by these cells. Moreover, the tolerance to endotoxin is conditioned by the posttranscriptional processes and posttranslational epigenetic modifications leading to the impairment of normal immune response for example by alterations in the expression of many genes encoding immune signaling mediators. The aim of this paper is to provide an overview existing knowledge on the modulation of activity of monocytes/macrophages in response to bacterial endotoxin and impaired immune responses.

Innate immune responses of equine monocytes cultured in equine platelet lysate.

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Naskou, Maria C; Norton, Natalie A; Copland, Ian B; Galipeau, Jacques; Peroni, John F

2018-01-01

Platelet lysate (PL) has been extensively used for the laboratory expansion of human mesenchymal stem cells (MSC) in order to avoid fetal bovine serum (FBS) which has been associated with immune-mediated host reactions and transmission of bovine-origin microbial contaminants. Before suggesting the routine use of PL for MSC culture, we wanted to further investigate whether PL alone might trigger inflammatory responses when exposed to reactive white blood cells such as monocytes. Our objectives were to evaluate the inflammatory profile of equine monocytes cultured with equine PL (ePL) and to determine if ePL can modulate the expression of inflammatory cytokines in lipopolysaccharide (LPS)-stimulated monocytes. In a first experiment, equine monocytes were isolated and incubated with donor horse serum (DHS), FBS, six individual donors ePL or pooled ePL from all horses. In a second experiment, monocytes were stimulated with E. coli LPS in the presence of 1, 5 or 10% DHS and/or pooled ePL. After 6h of incubation, cell culture supernatants were assayed via ELISA for production of the pro-inflammatory cytokines tumor necrosis factor alpha (TNF-α) and Interleukin 1β (IL-1β) as well as for the anti-inflammatory Interleukin 10 (IL-10). Equine monocytes incubated with pooled ePL produced significantly less TNF-α and significantly more IL-10 than monocytes incubated in FBS. A statistically significant difference was not identified for the production of IL-1β. The second experiment showed that pooled ePL added to LPS-stimulated equine monocytes resulted in a significant reduction in TNF-α and IL-1β production. IL-10 production was not significantly upregulated by the addition of ePL to LPS-stimulated monocytes. Finally, the addition of ePL to LPS-stimulated monocytes in the presence of various concentrations of DHS resulted to statistically significant decrease of TNF-α and IL-1β compared to the control groups. This is the first study to demonstrate that ePL suppresses

Generation and partial characterization of an eosinophil chemotactic cytokine produced by sensitized equine mononuclear cells stimulated with Strongylus vulgaris antigen.

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Dennis, V A; Klei, T R; Chapman, M R

1993-07-01

Supernatants generated by stimulation of peripheral blood mononuclear cells (PBMC) from Strongylus vulgaris sensitized or immunized ponies were assayed in vitro for eosinophil chemotactic activity (ECA) using the filter system in blind well chambers. The supernatants from these cultures were chemotactic for eosinophils, but not for neutrophils. Supernates from cultures of unsensitized PBMC stimulated with S. vulgaris antigen were not chemotactic for eosinophils. ECA was first detected in culture supernatants after 1.5 h of incubation and was dependent on both antigen and PBMC concentrations, but independent of serum concentrations. Both female and male S. vulgaris worm antigens stimulated ECA production from sensitized PBMC. ECA was not induced by in vitro stimulation of sensitized S. vulgaris PBMC by female Strongylus edentatus worm antigen. Partial characterization of the eosinophil chemotactic cytokine showed it to be nondialyzable, greater than 8000 molecular weight (MW), and sensitive to heating (56 and 95 degrees C), trypsin, and sodium metaperiodate treatments, suggesting that the cytokine is a protein containing some essential carbohydrate moieties. The cytokine described in this paper could partially contribute to the in vivo blood and tissue eosinophilia in experimental S. vulgaris infection.

Effects of Garlic Oil on the Migration of Neutrophil-Like Cell Studied by Using a Chemotactic Gradient Labchip

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Po-Chen Shih

2010-01-01

Full Text Available We have designed and fabricated a novel chemotactic gradient Labchip for studying cell migration quantitatively. Owing to the great potential of garlic and its preparations in developing antiinflammatory drugs, the aim of the present study is to investigate the effect of garlic oil on the locomotion of a neutrophil-like cell by measuring the dynamic features of cell migration including migration direction, average migration speed, chemotactic index (CI, and motility index (MI with the newly designed Labchip. We found that garlic oil treatment lowered the values of CI and MI and reduced the average speed of cell migration from 13 to 8 μm/min. The results indicate that garlic oil is a potential inhibitor for neutrophil-like cell migration and chemotactic responsiveness. By comparing with the effects of nocodazole and cytochalasin B, we also suggest that the antiinflammatory activity exhibited by garlic oil was mainly through inhibiting the assembly-disassembly processes of the cytoskeleton.

Monocyte transferrin-iron uptake in hereditary hemochromatosis

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Sizemore, D.J.; Bassett, M.L.

1984-01-01

Transferrin-iron uptake by peripheral blood monocytes was studied in vitro to test the hypothesis that the relative paucity of mononuclear phagocyte iron loading in hereditary hemochromatosis results from a defect in uptake of iron from transferrin. Monocytes from nine control subjects and 17 patients with hemochromatosis were cultured in the presence of 59Fe-labelled human transferrin. There was no difference in 59Fe uptake between monocytes from control subjects and monocytes from patients with hemochromatosis who had been treated by phlebotomy and who had normal body iron stores. However, 59Fe uptake by monocytes from iron-loaded patients with hemochromatosis was significantly reduced compared with either control subjects or treated hemochromatosis patients. It is likely that this was a secondary effect of iron loading since iron uptake by monocytes from treated hemochromatosis patients was normal. Assuming that monocytes in culture reflect mononuclear phagocyte iron metabolism in vivo, this study suggests that the relative paucity of mononuclear phagocyte iron loading in hemochromatosis is not related to an abnormality in transferrin-iron uptake by these cells

Monocyte activation, brain-derived neurotrophic factor (BDNF), and S100B in bipolar offspring: a follow-up study from adolescence into adulthood.

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Mesman, Esther; Hillegers, Manon Hj; Ambree, Oliver; Arolt, Volker; Nolen, Willem A; Drexhage, Hemmo A

2015-02-01

There is increasing evidence that both immune and neurochemical alterations are involved in the pathogenesis of bipolar disorder; however, their precise role remains unclear. In this study, we aimed to evaluate neuro-immune changes in a prospective study on children of patients with bipolar disorder. Bipolar offspring, from the prospective Dutch bipolar offspring study (n = 140), were evaluated cross-sectionally within a longitudinal context at adolescence, young adulthood, and adulthood. We examined the expression of 44 inflammation-related genes in monocytes, the cytokines pentraxin 3 (PTX3), chemokine ligand 2 (CCL2), and interleukin-1β (IL-1β), and brain-derived neurotrophic factor (BDNF) and S100 calcium binding protein B (S100B) in the serum of bipolar offspring and healthy controls. During adolescence, bipolar offspring showed increased inflammatory gene expression in monocytes, high serum PTX3 levels, but normal CCL2 levels. BDNF levels were decreased, while S100B levels were normal. During young adulthood, monocyte activation remained, although to a lesser degree. Serum PTX3 levels remained high, and signs of monocyte migration became apparent through increased CCL2 levels. BDNF and S100B levels were not measured. At adulthood, circulating monocytes had lost their activation state, but CCL2 levels remained increased. Both BDNF and S100B were now increased. Abnormalities were independent of psychopathology state at all stages. This study suggests an aberrant neuro-immune state in bipolar offspring, which followed a dynamic course from adolescence into adulthood and was present irrespective of lifetime or future mood disorders. We therefore assumed that the aberrant neuro-immune state reflects a general state of vulnerability for mood disorders rather than being of direct predictive value. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Hypoxia-inducible factor-1α regulates chemotactic migration of pancreatic ductal adenocarcinoma cells through directly transactivating the CX3CR1 gene.

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Tiansuo Zhao

Full Text Available CX3CR1 is an important chemokine receptor and regulates the chemotactic migration of pancreatic ductal adenocarcinoma (PDAC cells. Up to now, its regulatory mechanism remains largely undefined. Here, we report that hypoxia upregulates the expression of CX3CR1 in pancreatic cancer cells. When hypoxia-inducible factor (HIF-1α expression was knocked down in vitro and in vivo, the expression of CX3CR1 was significantly decreased. Chromatin immunoprecipitation assay demonstrated that HIF-1α bound to the hypoxia-response element (HRE; 5'-A/GCGTG-3' of CX3CR1 promoter under normoxia, and this binding was significantly enhanced under hypoxia. Overexpression of HIF-1α significantly upregulated the expression of luciferase reporter gene under the control of the CX3CR1 promoter in pancreatic cancer cells. Importantly, we demonstrated that HIF-1α may regulate cancer cell migration through CX3CR1. The HIF-1α/CX3CR1 pathway might represent a valuable therapeutic target to prevent invasion and distant metastasis in PDAC.

Granulocyte macrophage colony-stimulating factor enhances the modulatory effect of cytokines on monocyte-derived multinucleated giant cell formation and fungicidal activity against Paracoccidioides brasiliensis

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Magda Paula Pereira do Nascimento

2011-09-01

Full Text Available Multinucleated giant cells (MGC are cells present in characteristic granulomatous inflammation induced by intracellular infectious agents or foreign materials. The present study evaluated the modulatory effect of granulocyte macrophage colony-stimulating factor (GM-CSF in association with other cytokines such as interferon-gamma (IFN-γ, tumour necrosis factor-alpha, interleukin (IL-10 or transforming growth factor beta (TGF-β1 on the formation of MGC from human peripheral blood monocytes stimulated with Paracoccidioides brasiliensis antigen (PbAg. The generation of MGC was determined by fusion index (FI and the fungicidal activity of these cells was evaluated after 4 h of MGC co-cultured with viable yeast cells of P. brasiliensis strain 18 (Pb18. The results showed that monocytes incubated with PbAg and GM-CSF plus IFN-γ had a significantly higher FI than in all the other cultures, while the addition of IL-10 or TGF-β1 had a suppressive effect on MGC generation. Monocytes incubated with both pro and anti-inflammatory cytokines had a higher induction of foreign body-type MGC rather than Langhans-type MGC. MGC stimulated with PbAg and GM-CSF in association with the other cytokines had increased fungicidal activity and the presence of GM-CSF also partially inhibited the suppressive effects of IL-10 and TGF-β1. Together, these results suggest that GM-CSF is a positive modulator of PbAg-stimulated MGC generation and on the fungicidal activity against Pb18.

Granulocyte-Macrophage Colony-Stimulating Factor Amplification of Interleukin-1β and Tumor Necrosis Factor Alpha Production in THP-1 Human Monocytic Cells Stimulated with Lipopolysaccharide of Oral Microorganisms

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Baqui, A. A. M. A.; Meiller, Timothy F.; Chon, Jennifer J.; Turng, Been-Foo; Falkler, William A.

1998-01-01

Cytokines, including granulocyte-macrophage colony-stimulating factor (GM-CSF), are used to assist in bone marrow recovery during cancer chemotherapy. Interleukin-1β (IL-1β) and tumor necrosis factor alpha (TNF-α) play important roles in inflammatory processes, including exacerbation of periodontal diseases, one of the most common complications in patients who undergo this therapy. A human monocyte cell line (THP-1) was utilized to investigate IL-1β and TNF-α production following GM-CSF suppl...

Expression and divalent cation binding properties of the novel chemotactic inflammatory protein psoriasin

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Vorum, H; Madsen, Peder; Rasmussen, H H

1996-01-01

Psoriasin is a novel chemotactic inflammatory protein that possesses weak similarity to the S100 family members of Ca(2+)-binding proteins, and that is highly up-regulated in hyperproliferative psoriatic keratinocytes. Here we have used the psoriasin cDNA to express recombinant human (rh) psorias...

Bayesian spatio-temporal analysis and geospatial risk factors of human monocytic ehrlichiosis.

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Ram K Raghavan

Full Text Available Variations in spatio-temporal patterns of Human Monocytic Ehrlichiosis (HME infection in the state of Kansas, USA were examined and the relationship between HME relative risk and various environmental, climatic and socio-economic variables were evaluated. HME data used in the study was reported to the Kansas Department of Health and Environment between years 2005-2012, and geospatial variables representing the physical environment [National Land cover/Land use, NASA Moderate Resolution Imaging Spectroradiometer (MODIS], climate [NASA MODIS, Prediction of Worldwide Renewable Energy (POWER], and socio-economic conditions (US Census Bureau were derived from publicly available sources. Following univariate screening of candidate variables using logistic regressions, two Bayesian hierarchical models were fit; a partial spatio-temporal model with random effects and a spatio-temporal interaction term, and a second model that included additional covariate terms. The best fitting model revealed that spatio-temporal autocorrelation in Kansas increased steadily from 2005-2012, and identified poverty status, relative humidity, and an interactive factor, 'diurnal temperature range x mixed forest area' as significant county-level risk factors for HME. The identification of significant spatio-temporal pattern and new risk factors are important in the context of HME prevention, for future research in the areas of ecology and evolution of HME, and as well as climate change impacts on tick-borne diseases.

Molecular Mechanisms That Underlie the Dynamic Adaptation of Innate Monocyte Memory to Varying Stimulant Strength of TLR Ligands.

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Yuan, Ruoxi; Geng, Shuo; Li, Liwu

2016-01-01

In adaptation to rising stimulant strength, innate monocytes can be dynamically programed to preferentially express either pro- or anti-inflammatory mediators. Such dynamic innate adaptation or programing may bear profound relevance in host health and disease. However, molecular mechanisms that govern innate adaptation to varying strength of stimulants are not well understood. Using lipopolysaccharide (LPS), the model stimulant of toll-like-receptor 4 (TLR4), we reported that the expressions of pro-inflammatory mediators are preferentially sustained in monocytes adapted by lower doses of LPS, and suppressed/tolerized in monocytes adapted by higher doses of LPS. Mechanistically, monocytes adapted by super-low dose LPS exhibited higher levels of transcription factor, interferon regulatory factor 5 (IRF5), and reduced levels of transcriptional modulator B lymphocyte-induced maturation protein-1 (Blimp-1). Intriguingly, the inflammatory monocyte adaptation by super-low dose LPS is dependent upon TRAM/TRIF but not MyD88. Similar to LPS, we also observed biphasic inflammatory adaptation and tolerance in monocytes challenged with varying dosages of TLR7 agonist. In sharp contrast, rising doses of TLR3 agonist preferentially caused inflammatory adaptation without inducing tolerance. At the molecular level, the differential regulation of IRF5 and Blimp-1 coincides with unique monocyte adaptation dynamics by TLR4/7 and TLR3 agonists. Our study provides novel clue toward the understanding of monocyte adaptation and memory toward distinct TLR ligands.

Oxidative Mechanisms of Monocyte-Mediated Cytotoxicity

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Weiss, Stephen J.; Lobuglio, Albert F.; Kessler, Howard B.

1980-01-01

Human monocytes stimulated with phorbol myristate acetate were able to rapidly destroy autologous erythrocyte targets. Monocyte-mediated cytotoxicity was related to phorbol myristate acetate concentration and monocyte number. Purified preparations of lymphocytes were incapable of mediating erythrocyte lysis in this system. The ability of phorbol myristate acetate-stimulated monocytes to lyse erythrocyte targets was markedly impaired by catalase or superoxide dismutase but not by heat-inactivated enzymes or albumin. Despite a simultaneous requirement for superoxide anion and hydrogen peroxide in the cytotoxic event, a variety of hydroxyl radical and singlet oxygen scavengers did not effect cytolysis. However, tryptophan significantly inhibited cytotoxicity. The myeloperoxidase inhibitor cyanide enhanced erythrocyte destruction, whereas azide reduced it modestly. The inability of cyanide to reduce cytotoxicity coupled with the protective effect of superoxide dismutase suggests that cytotoxicity is independent of the classic myeloperoxidase system. We conclude that monocytes, stimulated with phorbol myristate acetate, generate superoxide anion and hydrogen peroxide, which together play an integral role in this cytotoxic mechanism.

Altered monocyte activation markers in Tourette’s syndrome: a case–control study

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Matz Judith

2012-05-01

Full Text Available Abstract Background Infections and immunological processes are likely to be involved in the pathogenesis of Tourette’s syndrome (TS. To determine possible common underlying immunological mechanisms, we focused on innate immunity and studied markers of inflammation, monocytes, and monocyte-derived cytokines. Methods In a cross-sectional study, we used current methods to determine the number of monocytes and levels of C-reactive protein (CRP in 46 children, adolescents, and adult patients suffering from TS and in 43 healthy controls matched for age and sex. Tumor necrosis factor alpha (TNF-alpha, interleukin 6 (IL-6, soluble CD14 (sCD14, IL1-receptor antagonist (IL1-ra, and serum neopterin were detected by immunoassays. Results We found that CRP and neopterin levels and the number of monocytes were significantly higher in TS patients than in healthy controls. Serum concentrations of TNF-alpha, sIL1-ra, and sCD14 were significantly lower in TS patients. All measured values were within normal ranges and often close to detection limits. Conclusions The present results point to a monocyte dysregulation in TS. This possible dysbalance in innate immunity could predispose to infections or autoimmune reactions.

Effects of Porphyromonas gingivalis LipopolysaccharideTolerized Monocytes on Inflammatory Responses in Neutrophils.

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Xiang-Qing Zhu

Full Text Available Periodontitis is a chronic inflammatory disease induced by bacteria. Exposure of the host to periodontal pathogens and their virulence factors induces a state of hyporesponsiveness to subsequent stimulations, which is termed endotoxin tolerance. The role and mechanism of lipopolysaccharide (LPS-tolerized monocytes in inflammatory responses in neutrophils are currently unclear. Here, conditioned supernatants were collected from THP-1 cells treated with or without repeated 1 μg/ml Porphyromonas gingivalis (P.gingivalis LPS. The chemotactic response of freshly isolated neutrophils recruited by supernatants was determined by a transwell migration assay, which demonstrated a reduced migration of neutrophils stimulated with supernatants from tolerized THP-1 cells in comparison to non-tolerized THP-1 cells. In addition, there was a marked increase in reactive oxygen species (ROS generation and a significant decrease in Caspase 3 activities in neutrophils treated with supernatants from THP-1 cells that were treated repeatedly with P.gingivalis LPS in comparison to single treatment. A cytokine antibody array was then used to assess cytokine expression patterns in THP-1 cells. In tolerized THP-1 cells, 43 cytokine (43/170 expression levels were decreased, including chemokine ligand 23 (CCL23 and IFN-γ, while 11 cytokine (11/170 expression levels were increased, such as death receptor 6 (DR6. Furthermore, there was decreased production of IFN-γ and epithelial neutrophil activating peptide-78 (ENA-78 in THP-1 cells after stimulation with repeated P. gingivalis LPS in comparison to single challenge, which was confirmed by ELISA. Therefore, P.gingivalis LPS- tolerized THP-1 cells were able to depress neutrophil chemotaxis and apoptosis, and contribute to respiratory burst, which might be related to the changes in cytokine expression patterns in THP-1 cells.

HIV-1 Latency in Monocytes/Macrophages

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Amit Kumar

2014-04-01

Full Text Available Human immunodeficiency virus type 1 (HIV-1 targets CD4+ T cells and cells of the monocyte/macrophage lineage. HIV pathogenesis is characterized by the depletion of T lymphocytes and by the presence of a population of cells in which latency has been established called the HIV-1 reservoir. Highly active antiretroviral therapy (HAART has significantly improved the life of HIV-1 infected patients. However, complete eradication of HIV-1 from infected individuals is not possible without targeting latent sources of infection. HIV-1 establishes latent infection in resting CD4+ T cells and findings indicate that latency can also be established in the cells of monocyte/macrophage lineage. Monocyte/macrophage lineage includes among others, monocytes, macrophages and brain resident macrophages. These cells are relatively more resistant to apoptosis induced by HIV-1, thus are important stable hideouts of the virus. Much effort has been made in the direction of eliminating HIV-1 resting CD4+ T-cell reservoirs. However, it is impossible to achieve a cure for HIV-1 without considering these neglected latent reservoirs, the cells of monocyte/macrophage lineage. In this review we will describe our current understanding of the mechanism of latency in monocyte/macrophage lineage and how such cells can be specifically eliminated from the infected host.

Exposure of Monocytes to Lipoarabinomannan Promotes Their Differentiation into Functionally and Phenotypically Immature Macrophages

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Leslie Chávez-Galán

2015-01-01

Full Text Available Lipoarabinomannan (LAM is a lipid virulence factor secreted by Mycobacterium tuberculosis (Mtb, the etiologic agent of tuberculosis. LAM can be measured in the urine or serum of tuberculosis patients (TB-patients. Circulating monocytes are the precursor cells of alveolar macrophages and might be exposed to LAM in patients with active TB. We speculated that exposing monocytes to LAM could produce phenotypically and functionally immature macrophages. To test our hypothesis, human monocytes were stimulated with LAM (24–120 hours and various readouts were measured. The study showed that when monocytes were exposed to LAM, the frequency of CD68+, CD33+, and CD86+ macrophages decreased, suggesting that monocyte differentiation into mature macrophages was affected. Regarding functionality markers, TLR2+ and TLR4+ macrophages also decreased, but the percentage of MMR+ expression did not change. LAM-exposed monocytes generated macrophages that were less efficient in producing proinflammatory cytokines such as TNF-α and IFN-γ; however, their phagocytic capacity was not modified. Taken together, these data indicate that LAM exposure influenced monocyte differentiation and produced poorly functional macrophages with a different phenotype. These results may help us understand how mycobacteria can limit the quality of the innate and adaptive immune responses.

Global solution for a chemotactic haptotactic model of cancer invasion

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Tao, Youshan; Wang, Mingjun

2008-10-01

This paper deals with a mathematical model of cancer invasion of tissue recently proposed by Chaplain and Lolas. The model consists of a reaction-diffusion-taxis partial differential equation (PDE) describing the evolution of tumour cell density, a reaction-diffusion PDE governing the evolution of the proteolytic enzyme concentration and an ordinary differential equation modelling the proteolysis of the extracellular matrix (ECM). In addition to random motion, the tumour cells are directed not only by haptotaxis (cellular locomotion directed in response to a concentration gradient of adhesive molecules along the ECM) but also by chemotaxis (cellular locomotion directed in response to a concentration gradient of the diffusible proteolytic enzyme). In one space dimension, the global existence and uniqueness of a classical solution to this combined chemotactic-haptotactic model is proved for any chemotactic coefficient χ > 0. In two and three space dimensions, the global existence is proved for small χ/μ (where μ is the logistic growth rate of the tumour cells). The fundamental point of proof is to raise the regularity of a solution from L1 to Lp (p > 1). Furthermore, the existence of blow-up solutions to a sub-model in two space dimensions for large χ shows, to some extent, that the condition that χ/μ is small is necessary for the global existence of a solution to the full model.

Monocytes/macrophages support mammary tumor invasivity by co-secreting lineage-specific EGFR ligands and a STAT3 activator

International Nuclear Information System (INIS)

Vlaicu, Philip; Mertins, Philipp; Mayr, Thomas; Widschwendter, Peter; Ataseven, Beyhan; Högel, Bernhard; Eiermann, Wolfgang; Knyazev, Pjotr; Ullrich, Axel

2013-01-01

Tumor-associated macrophages (TAM) promote malignant progression, yet the repertoire of oncogenic factors secreted by TAM has not been clearly defined. We sought to analyze which EGFR- and STAT3-activating factors are secreted by monocytes/macrophages exposed to tumor cell-secreted factors. Following exposure of primary human monocytes and macrophages to supernatants of a variety of tumor cell lines, we have analyzed transcript and secreted protein levels of EGFR family ligands and of STAT3 activators. To validate our findings, we have analyzed TAM infiltration levels, systemic and local protein levels as well as clinical data of primary breast cancer patients. Primary human monocytes and macrophages respond to tumor cell-derived factors by secreting EGFR- and STAT3-activating ligands, thus inducing two important oncogenic pathways in carcinoma cells. Tumor cell-secreted factors trigger two stereotype secretory profiles in peripheral blood monocytes and differentiated macrophages: monocytes secrete epiregulin (EREG) and oncostatin-M (OSM), while macrophages secrete heparin-binding EGF-like growth factor (HB-EGF) and OSM. HB-EGF and OSM cooperatively induce tumor cell chemotaxis. HB-EGF and OSM are co-expressed by TAM in breast carcinoma patients, and plasma levels of both ligands correlate strongly. Elevated HB-EGF levels accompany TAM infiltration, tumor growth and dissemination in patients with invasive disease. Our work identifies systemic markers for TAM involvement in cancer progression, with the potential to be developed into molecular targets in cancer therapy

ADMA induces monocyte adhesion via activation of chemokine receptors in cultured THP-1 cells.

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Chen, Meifang; Li, Yuanjian; Yang, Tianlun; Wang, Yongjin; Bai, Yongping; Xie, Xiumei

2008-08-01

Asymmetric dimethylarginine (ADMA), an endogenous NOS inhibitor, is also an important inflammatory factor contributing to the development of atherosclerosis (AS). The present study was to test the effect of ADMA on angiotensin (Ang) II-induced monocytic adhesion. Human monocytoid cells (THP-1) or isolated peripheral blood monocyte cells (PBMCs) were incubated with Ang II (10(-6)M) or exogenous ADMA (30 microM) for 4 or 24h in the absence or presence of losartan or antioxidant PDTC. In cultured THP-1 cells, Ang II (10(-6)M) for 24h elevated the level of ADMA in the medium, upregulated the protein expression of protein arginine methyltransferase (PRMT) and decreased the activity of dimethylarginine dimethylaminohydrolase (DDAH). Both of Ang II and ADMA increased monocytic adhesion to human umbilical vein endothelial cells (HUVECs), elevated the levels of monocyte chemoattractant protein (MCP)-1, interleukin (IL)-8 and tumor necrosis factor (TNF)-alpha and upregulated CCR(2) and CXCR(2) mRNA expression, concomitantly with increase in reactive oxygen species (ROS) generation and activation of nuclear factor (NF)-kappaB. Pretreatment with losartan (10 microM) or PDTC (10 microM) abolished the effects mediated by Ang II or ADMA. In isolated PBMCs from healthy individuals, ADMA upregulated the expression of CXCR(2) mRNA, which was attenuated by losartan (10 microM), however, ADMA had no effect on surface protein expression of CCR(2). The present results suggest that ADMA may be involved in monocytic adhesion induced by Ang II via activation of chemokine receptors by ROS/NF-kappaB pathway.

Synthesis of complement factor B by the human monocyte U-937 cell line. Augmentation by immunostimulatory agents

International Nuclear Information System (INIS)

Minta, J.O.

1988-01-01

The human pre-monocytic cell line U-937 was shown to synthesize and to secrete increasing amounts of factor B in short term cultures in serum-free medium containing BSA. The kinetics of factor B production were higher on day 2 than on days 1 and 3. The production of factor B was reversibly inhibited by cycloheximide, indicating de novo synthesis. Metabolic labeling with [ 35 S]-methionine and SDS-PAGE analysis revealed that both intracellular and secreted factor B were single-chain proteins with similar m.w. (90,000), which co-migrated with purified plasma factor B. Incubation of U-937 cells with the immunostimulants PMA, LPS, IFN-gamma, and IL-1 resulted in a dose-dependent augmentation of factor B production. A 24-h exposure to IL-1 was shown to be required for maximal stimulation. A combination of suboptimal doses of LPS and IFN-gamma was shown to exert a synergistic effect on factor B production. The U-937 cell line is thus a valuable model for the study of the regulation of the factor B gene expression

Platelet-derived growth factor (PDGF) B-chain gene expression by activated blood monocytes precedes the expression of the PDGF A-chain gene

International Nuclear Information System (INIS)

Martinet, Y.; Jaffe, H.A.; Yamauchi, K.; Betsholtz, C.; Westermark, B.; Heldin, C.H.; Crystal, R.G.

1987-01-01

When activated, normal human blood monocytes are known to express the c-sis proto-oncogene coding for PDGF B-chain. Since normal human platelet PDGF molecules are dimers of A and B chains and platelets and monocytes are derived from the same marrow precursors, activated blood monocytes were simultaneously evaluated for their expression of PDGF A and B chain genes. Human blood monocytes were purified by adherence, cultured with or without activation by lipopolysaccharide and poly(A)+ RNA evaluated using Northern analysis and 32 P-labeled A-chain and B-chain (human c-sis) probes. Unstimulated blood monocytes did not express either A-chain or B-chain genes. In contrast, activated monocytes expressed a 4.2 kb mRNA B-chain transcript at 4 hr, but the B-chain mRNA levels declined significantly over the next 18 hr. In comparison, activated monocytes expressed very little A-chain mRNA at 4 hr, but at 12 hr 1.9, 2.3, and 2.8 kb transcripts were observed and persisted through 24 hr. Thus, activation of blood monocytes is followed by PDGF B-chain gene expression preceding PDGF A-chain gene expression, suggesting a difference in the regulation of the expression of the genes for these two chains by these cells

Transcellular lipoxygenase metabolism between monocytes and platelets

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Bigby, T.D.; Meslier, N. (Univ. of California, San Francisco (USA))

1989-09-15

We have examined the effects of co-culture and in vitro co-stimulation on lipoxygenase metabolism in monocytes and platelets. Monocytes were obtained from the peripheral blood of normal volunteers by discontinuous gradient centrifugation and adherence to tissue culture plastic. Platelets were obtained from the platelet-rich plasma of the same donor. When 10(9) platelets and 2.5 x 10(6) monocytes were co-stimulated with 1 microM A23187, these preparations released greater quantities of 12(S)-hydroxy-10-trans-5,8,14-cis-eicosatetraenoic acid, 5(S),12-(S)dihydroxy-6,10-trans-8,14-cis-eicosatetraenoic acid, and leukotriene C4, 5(S)-hydroxy-6(R)-S-glutathionyl-7,9-trans-11,14-cis-eicosatetraenoic (LTC4) when compared with monocytes alone. Release of arachidonic acid, 5-HETE, delta 6-trans-LTB4, and delta 6-trans-12-epi-LTB4 from monocytes was decreased in the presence of platelets. A dose-response curve was constructed and revealed that the above changes became evident when the platelet number exceeded 10(7). Dual radiolabeling experiments with 3H- and 14C-arachidonic acid revealed that monocytes provided arachidonic acid, 5-HETE, and LTA4 for further metabolism by the platelet. Monocytes did not metabolize platelet intermediates detectably. In addition, as much as 1.2 microM 12(S)-hydroxy-10-trans-5,8,14-cis-eicosatetraenoic acid and 12(S)-hydroperoxy-10-trans-5,8,14-cis-eicosatetraenoic acid had no effect on monocyte lipoxygenase metabolism. Platelets were capable of converting LTA4 to LTC4, but conversion of LTA4 to LTB4 was not detected. We conclude that the monocyte and platelet lipoxygenase pathways undergo a transcellular lipoxygenase interaction that differs from the interaction of the neutrophil and platelet lipoxygenase pathways. In this interaction monocytes provide intermediate substrates for further metabolic conversion by platelets in an unidirectional manner.

Monocyte matrix metalloproteinase production in Type 2 diabetes and controls – a cross sectional study

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Davies Isabel R

2003-03-01

Full Text Available Abstract Background Coronary plaque rupture may result from localised over expression of matrix metalloproteinases (MMPs within the plaque by infiltrating monocyte – macrophages. As MMP expression can be promoted by the modified lipoproteins, oxidative stress and hyperglycaemia that characterises Type 2 diabetes, we hypothesised that peripheral monocytes in these patients, exposed to these factors in vivo, would demonstrate increased MMP production compared to controls. Methods We examined peripheral venous monocyte expression of MMP and tissue inhibitor of metalloproteinase-1 (TIMP-1 in 18 controls and 22 subjects with Type 2 diabetes and no previous cardiovascular complications. Results No significant difference in MMP-1, 3 or 9 or TIMP-1 production was observed between control and diabetes groups. Conclusions Monocyte MMP-1, 3, and 9, and TIMP-1, production are not abnormal in Type 2 diabetes. This data cannot be extrapolated to monocyte – macrophage behaviour in the vessel wall, but it does suggest MMP and TIMP-1 expression prior to monocyte infiltration and transformation are not abnormal in Type 2 diabetes.

Enhanced basophil histamine release and neutrophil chemotactic activity predispose grain dust-induced airway obstruction.

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Park, H; Jung, K; Kang, K; Nahm, D; Cho, S; Kim, Y

1999-04-01

The pathogenic mechanism of grain dust (GD)-induced occupational asthma (OA) remains unclear. To understand further the mechanism of GD-induced OA. Fifteen employees working in a same GD industry, complaining of work-related respiratory symptoms, were enrolled and were divided into two groups according to the GD-bronchoprovocation test (BPT) result: six positive responders were grouped as group III, nine negative responders as group II and five healthy controls as group I. Serum GD-specific immunoglobulin (Ig)E (sIgE), specific IgG (sIgG) and specific IgG4 (sIgG4) antibodies were detected by enzyme-linked immunosorbent assay. Basophil histamine release was measured by the autofluorometric method, and changes of serum neutrophil chemotactic activity were observed by the Boyden chamber method. For clinical parameters such as degree of airway hyperresponsiveness to methacholine, duration of respiratory symptoms, exposure duration, and prevalences of serum sIgE, sIgG and sIgG4 antibodies, there were no significant differences between group II and III (P > 0.05, respectively). Serum neutrophil chemotactic activity increased significantly at 30 min and decreased at 240 min after the GD-BPT in group III subjects (P 0.05). Basophil histamine release induced by GD was significantly higher in group III than those of group I or group II (P < 0.05, respectively), while minimal release of anti-IgG4 antibodies was noted in all three groups. These results suggest that enhanced basophil histamine release and serum neutrophil chemotactic activity might contribute to the development of GD-induced occupational asthma.

LEGO bricks used as chemotactic chambers: evaluation by a computer-assisted image analysis technique.

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Azzarà, A; Chimenti, M

2004-01-01

One of the main techniques used to explore neutrophil motility, employs micropore filters in chemotactic chambers. Many new models have been proposed, in order to perform multiple microassays in a rapid, inexpensive and reproducible way. In this work, LEGO bricks have been used as chemotactic chambers in the evaluation of neutrophil random motility and chemotaxis and compared with conventional Boyden chambers in a "time-response" experiment. Neutrophil motility throughout the filters was evaluated by means of an image-processing workstation, in which a dedicated algorithm recognizes and counts the cells in several fields and focal planes throughout the whole filter; correlates counts and depth values; performs a statistical analysis of data; calculates the true value of neutrophil migration; determines the distribution of cells; and displays the migration pattern. By this method, we found that the distances travelled by the cells in conventional chambers and in LEGO bricks were perfectly identical, both in random migration and under chemotactic conditions. Moreover, no interference with the physiological behaviour of neutrophils was detectable. In fact, the kinetics of migration was identical both in random migration (characterized by a gaussian pattern) and in chemotaxis (characterized by a typical stimulation peak, previously identified by our workstation). In conclusion, LEGO bricks are extremely precise devices. They are simple to use and allow the use of small amounts of chemoattractant solution and cell suspension, supplying by itself a triplicate test. LEGO bricks are inexpensive, fast and suitable for current diagnostic activity or for research investigations in every laboratory.

An unusual protein kinase phosphorylates the chemotactic receptor of Dictystelium discoideum

International Nuclear Information System (INIS)

Meier, K.; Klein, C.

1988-01-01

The authors report the cAMP-dependent phosphorylation of the chemotactic receptor of Dictyostelium discoideum in partially purified plasma membranes. The protein kinase responsible for receptor phosphorylation is associated with this fraction and preferentially phosphorylates the ligand-occupied form of the receptor. 8-Azido[ 32 P]cAMP labeling of the cell surface has shown that the cAMP receptor exists in two forms. A 45-kDa protein is predominant on unstimulated cells. cAMP stimulation results in an increased receptor phosphorylation such that the receptor migrates on NaDodSO 4 /PAGE as a 47-kDa protein. Phosphorylation of the chemotactic receptor is not detected in membrane preparations unless cAMP is added to the incubation mixture. Only under those conditions is the phosphorylated 47-kDa form observed. The requirement for cAMP reflects the fact that the kinase involved preferentially uses the ligand-occupied receptor as a substrate. In vitro phosphorylation of the receptor does not involve tyrosine residues. The enzyme does not appear to be a cAMP- or cGMP-dependent protein kinase nor is it sensitive to guanine nucleotides, Ca 2+ /calmodulin, Ca 2+ /phospholipid, or EGTA. Similarities with the β-adrenergic receptor protein kinase are discussed

Induction of autophagy is essential for monocyte-macrophage differentiation

OpenAIRE

Zhang, Yan; Morgan, Michael J.; Chen, Kun; Choksi, Swati; Liu, Zheng-gang

2012-01-01

Monocytes are programmed to undergo apoptosis in the absence of stimulation. Stimuli that promote monocyte-macrophage differentiation not only cause cellular changes, but also prevent the default apoptosis of monocytes. In the present study, we demonstrate that autophagy is induced when monocytes are triggered to differentiate and that the induction of autophagy is pivotal for the survival and differentiation of monocytes. We also show that inhibition of autophagy results in apoptosis of cell...

Platelet-, monocyte-derived and tissue factor-carrying circulating microparticles are related to acute myocardial infarction severity.

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Gemma Chiva-Blanch

Full Text Available Circulating microparticles (cMPs are phospholipid-rich vesicles released from cells when activated or injured, and contribute to the formation of intracoronary thrombi. Tissue factor (TF, CD142 is the main trigger of fibrin formation and TF-carrying cMPs are considered one of the most procoagulant cMPs. Similar types of atherosclerotic lesions may lead to different types of AMI, although the mechanisms behind are unresolved. Therefore, we aimed to investigate the phenotype of cMPs found in plasma of ACS patients and its relation to AMI severity and thrombotic burden.In a cross-sectional study, two hundred patients aged 75±4 years were included in the study 2-8 weeks after suffering an AMI. Annexin V positive (AV+-cMPs derived from blood and vascular cells were measured by flow cytometry. Plasma procoagulant activity (TF-PCA was measured through a chromogenic assay.STEMI patients (n = 75 showed higher levels of platelet-derived cMPs [CD61+/AV+, CD31+/AV+, CD42b+/AV+ and CD31+/CD42b+/AV+, P = 0.048, 0.038, 0.009 and 0.006, respectively], compared to NSTEMI patients (n = 125. Patients who suffered a heart failure during AMI (n = 17 had increased levels of platelet (CD61+-and monocyte (CD14+-derived cMPs carrying TF (CD142+ (P<0.0001 and 0.004, respectively. Additionally, NYHA class III (n = 23 patients showed higher levels of CD142+/AV+, CD14+/AV+ and CD14+/CD142+/AV+ cMPs than those in class I/II (P = 0.001, 0.015 and 0.014, respectively. The levels of these cMPs positively correlated with TF-PCA (r≥0.166, P≤0.027, all.Platelets and monocytes remain activated in AMI patients treated as per guidelines and release cMPs that discriminate AMI severity. Therefore, TF-MPs, and platelet- and monocyte-MPs may reflect thrombotic burden in AMI patients.

Development of pro-inflammatory phenotype in monocytes after engulfing Hb-activated platelets in hemolytic disorders.

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Singhal, Rashi; Chawla, Sheetal; Rathore, Deepak K; Bhasym, Angika; Annarapu, Gowtham K; Sharma, Vandana; Seth, Tulika; Guchhait, Prasenjit

2017-02-01

Monocytes and macrophage combat infections and maintain homeostatic balance by engulfing microbes and apoptotic cells, and releasing inflammatory cytokines. Studies have described that these cells develop anti-inflammatory properties upon recycling the free-hemoglobin (Hb) in hemolytic conditions. While investigating the phenotype of monocytes in two hemolytic disorders-paroxysmal nocturnal hemoglobinuria (PNH) and sickle cell disease (SCD), we observed a high number of pro-inflammatory (CD14 + CD16 hi ) monocytes in these patients. We further investigated in vitro the phenotype of these monocytes and found an estimated 55% of CD14 + cells were transformed into the CD14 + CD16 hi subset after engulfing Hb-activated platelets. The CD14 + CD16 hi monocytes, which were positive for both intracellular Hb and CD42b (platelet marker), secreted significant amounts of TNF-α and IL-1β, unlike monocytes treated with only free Hb, which secreted more IL-10. We have shown recently the presence of a high number of Hb-bound hyperactive platelets in patients with both diseases, and further investigated if the monocytes engulfed these activated platelets in vivo. As expected, we found 95% of CD14 + CD16 hi monocytes with both intracellular Hb and CD42b in both diseases, and they expressed high TNF-α. Furthermore our data showed that these monocytes whether from patients or developed in vitro after treatment with Hb-activated platelets, secreted significant amounts of tissue factor. Besides, these CD14 + CD16 hi monocytes displayed significantly decreased phagocytosis of E. coli. Our study therefore suggests that this alteration of monocyte phenotype may play a role in the increased propensity to pro-inflammatory/coagulant complications observed in these hemolytic disorders-PNH and SCD. Copyright © 2016 Elsevier Inc. All rights reserved.

Functional role of monocytes and macrophages for the inflammatory response in acute liver injury

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Henning W Zimmermann

2012-10-01

Full Text Available Different etiologies such as drug toxicity, acute viral hepatitis B or acetaminophen poisoning can cause acute liver injury (ALI or even acute liver failure (ALF. Excessive cell death of hepatocytes in the liver is known to result in a strong hepatic inflammation. Experimental murine models of liver injury highlighted the importance of hepatic macrophages, so-called Kupffer cells, for initiating and driving this inflammatory response by releasing proinflammatory cytokines and chemokines including tumor necrosis factor (TNF, interleukin-6 (IL-6, IL-1-beta or monocyte chemoattractant protein 1 (MCP-1, CCL2 as well as activating other non-parenchymal liver cells, e.g. endothelial or hepatic stellate cells (HSC. Many of these proinflammatory mediators can trigger hepatocytic cell death pathways, e.g. via caspase activation, but also activate protective signaling pathways, e.g. via nuclear factor kappa B (NF-kB. Recent studies in mice demonstrated that these macrophage actions largely depend on the recruitment of monocytes into the liver, namely of the inflammatory Ly6c+ (Gr1+ monocyte subset as precursors of tissue macrophages. The chemokine receptor CCR2 and its ligand MCP-1/CCL2 promote monocyte subset infiltration upon liver injury. In contrast, the chemokine receptor CX3CR1 and its ligand fractalkine (CX3CL1 are important negative regulators of monocyte infiltration by controlling their survival and differentiation into functionally diverse macrophage subsets upon injury. The recently identified cellular and molecular pathways for monocyte subset recruitment, macrophage differentiation and interactions with other hepatic cell types in the injured liver may therefore represent interesting novel targets for future therapeutic approaches in ALF.

Plant-Adapted Escherichia coli Show Increased Lettuce Colonizing Ability, Resistance to Oxidative Stress and Chemotactic Response

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Dublan, Maria de los Angeles; Ortiz-Marquez, Juan Cesar Federico; Lett, Lina; Curatti, Leonardo

2014-01-01

Background Escherichia coli is a widespread gut commensal and often a versatile pathogen of public health concern. E. coli are also frequently found in different environments and/or alternative secondary hosts, such as plant tissues. The lifestyle of E. coli in plants is poorly understood and has potential implications for food safety. Methods/Principal Findings This work shows that a human commensal strain of E. coli K12 readily colonizes lettuce seedlings and produces large microcolony-like cell aggregates in leaves, especially in young leaves, in proximity to the vascular tissue. Our observations strongly suggest that those cell aggregates arise from multiplication of single bacterial cells that reach those spots. We showed that E. coli isolated from colonized leaves progressively colonize lettuce seedlings to higher titers, suggesting a fast adaptation process. E. coli cells isolated from leaves presented a dramatic rise in tolerance to oxidative stress and became more chemotactic responsive towards lettuce leaf extracts. Mutant strains impaired in their chemotactic response were less efficient lettuce colonizers than the chemotactic isogenic strain. However, acclimation to oxidative stress and/or minimal medium alone failed to prime E. coli cells for enhanced lettuce colonization efficiency. Conclusion/Significance These findings help to understand the physiological adaptation during the alternative lifestyle of E. coli in/on plant tissues. PMID:25313845

Enhancement of proinflammatory and procoagulant responses to silica particles by monocyte-endothelial cell interactions

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Liu Xin

2012-09-01

Full Text Available Abstract Background Inorganic particles, such as drug carriers or contrast agents, are often introduced into the vascular system. Many key components of the in vivo vascular environment include monocyte-endothelial cell interactions, which are important in the initiation of cardiovascular disease. To better understand the effect of particles on vascular function, the present study explored the direct biological effects of particles on human umbilical vein endothelial cells (HUVECs and monocytes (THP-1 cells. In addition, the integrated effects and possible mechanism of particle-mediated monocyte-endothelial cell interactions were investigated using a coculture model of HUVECs and THP-1 cells. Fe3O4 and SiO2 particles were chosen as the test materials in the present study. Results The cell viability data from an MTS assay showed that exposure to Fe3O4 or SiO2 particles at concentrations of 200 μg/mL and above significantly decreased the cell viability of HUVECs, but no significant loss in viability was observed in the THP-1 cells. TEM images indicated that with the accumulation of SiO2 particles in the cells, the size, structure and morphology of the lysosomes significantly changed in HUVECs, whereas the lysosomes of THP-1 cells were not altered. Our results showed that reactive oxygen species (ROS generation; the production of interleukin (IL-6, IL-8, monocyte chemoattractant protein 1 (MCP-1, tumor necrosis factor (TNF-α and IL-1β; and the expression of CD106, CD62E and tissue factor in HUVECs and monocytes were significantly enhanced to a greater degree in the SiO2-particle-activated cocultures compared with the individual cell types alone. In contrast, exposure to Fe3O4 particles had no impact on the activation of monocytes or endothelial cells in monoculture or coculture. Moreover, using treatment with the supernatants of SiO2-particle-stimulated monocytes or HUVECs, we found that the enhancement of proinflammatory response by SiO2

Monocyte Subsets in Schistosomiasis Patients with Periportal Fibrosis

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Jamille Souza Fernandes

2014-01-01

Full Text Available A major issue with Schistosoma mansoni infection is the development of periportal fibrosis, which is predominantly caused by the host immune response to egg antigens. Experimental studies have pointed to the participation of monocytes in the pathogenesis of liver fibrosis. The aim of this study was to characterize the subsets of monocytes in individuals with different degrees of periportal fibrosis secondary to schistosomiasis. Monocytes were classified into classical (CD14++CD16−, intermediate (CD14++CD16+, and nonclassical (CD14+CD16++. The expressions of monocyte markers and cytokines were assessed using flow cytometry. The frequency of classical monocytes was higher than the other subsets. The expression of HLA-DR, IL-6, TNF-α, and TGF-β was higher in monocytes from individuals with moderate to severe fibrosis as compared to other groups. Although no differences were observed in receptors expression (IL-4R and IL-10R between groups of patients, the expression of IL-12 was lower in monocytes from individuals with moderate to severe fibrosis, suggesting a protective role of this cytokine in the development of fibrosis. Our data support the hypothesis that the three different monocyte populations participate in the immunopathogenesis of periportal fibrosis, since they express high levels of proinflammatory and profibrotic cytokines and low levels of regulatory markers.

Transcript and protein analysis reveals better survival skills of monocyte-derived dendritic cells compared to monocytes during oxidative stress.

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Ilse Van Brussel

Full Text Available BACKGROUND: Dendritic cells (DCs, professional antigen-presenting cells with the unique ability to initiate primary T-cell responses, are present in atherosclerotic lesions where they are exposed to oxidative stress that generates cytotoxic reactive oxygen species (ROS. A large body of evidence indicates that cell death is a major modulating factor of atherogenesis. We examined antioxidant defence systems of human monocyte-derived (moDCs and monocytes in response to oxidative stress. METHODS: Oxidative stress was induced by addition of tertiary-butylhydroperoxide (tert-BHP, 30 min. Cellular responses were evaluated using flow cytometry and confocal live cell imaging (both using 5-(and-6-chloromethyl-2,7-dichlorodihydrofluorescein diacetate, CM-H(2DCFDA. Viability was assessed by the neutral red assay. Total RNA was extracted for a PCR profiler array. Five genes were selected for confirmation by Taqman gene expression assays, and by immunoblotting or immunohistochemistry for protein levels. RESULTS: Tert-BHP increased CM-H(2DCFDA fluorescence and caused cell death. Interestingly, all processes occurred more slowly in moDCs than in monocytes. The mRNA profiler array showed more than 2-fold differential expression of 32 oxidative stress-related genes in unstimulated moDCs, including peroxiredoxin-2 (PRDX2, an enzyme reducing hydrogen peroxide and lipid peroxides. PRDX2 upregulation was confirmed by Taqman assays, immunoblotting and immunohistochemistry. Silencing PRDX2 in moDCs by means of siRNA significantly increased CM-DCF fluorescence and cell death upon tert-BHP-stimulation. CONCLUSIONS: Our results indicate that moDCs exhibit higher intracellular antioxidant capacities, making them better equipped to resist oxidative stress than monocytes. Upregulation of PRDX2 is involved in the neutralization of ROS in moDCs. Taken together, this points to better survival skills of DCs in oxidative stress environments, such as atherosclerotic plaques.

Substrate-driven chemotactic assembly in an enzyme cascade

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Zhao, Xi; Palacci, Henri; Yadav, Vinita; Spiering, Michelle M.; Gilson, Michael K.; Butler, Peter J.; Hess, Henry; Benkovic, Stephen J.; Sen, Ayusman

2018-03-01

Enzymatic catalysis is essential to cell survival. In many instances, enzymes that participate in reaction cascades have been shown to assemble into metabolons in response to the presence of the substrate for the first enzyme. However, what triggers metabolon formation has remained an open question. Through a combination of theory and experiments, we show that enzymes in a cascade can assemble via chemotaxis. We apply microfluidic and fluorescent spectroscopy techniques to study the coordinated movement of the first four enzymes of the glycolysis cascade: hexokinase, phosphoglucose isomerase, phosphofructokinase and aldolase. We show that each enzyme independently follows its own specific substrate gradient, which in turn is produced by the preceding enzymatic reaction. Furthermore, we find that the chemotactic assembly of enzymes occurs even under cytosolic crowding conditions.

The radioactive labeling of monocytes

International Nuclear Information System (INIS)

Ensing, G.J.

1985-01-01

With the aim of studying a possible relationship between circulating monocytes and Sternberg-Reed cells investigations were started on the specific labeling of monocytes. In this thesis the literature on the pertinent data has been reviewed and a series of experiments on the monocyte labeling procedure has been described. The principles of cell labeling with radioactive compounds were discussed. 1. Total separation of the particular cell population to be labeled and subsequent labeling with a non-specific radiopharmaceutical. 2. Specific cell labeling in a mixture of cell types based on a well defined affinity of the cell under study for the radiopharmaceutical used. Next the radionuclides that can be used for cell labeling purposes were discussed with special attention for 111 In and its chelates. The principles of radiodosimetry were also discussed shortly. This section was focussed on the radiation dose the labeled cells receive because of the intracellular localized radioactivity. The radiation burden is high in comparison to amounts of radiation known to affect cell viability. A newly developed method for labeling monocytes specifically by phagocytosis of 111 In-Fe-colloid without apparent loss of cells was described in detail. (Auth.)

The Toll-like receptor 1/2 agonists Pam(3) CSK(4) and human β-defensin-3 differentially induce interleukin-10 and nuclear factor-κB signalling patterns in human monocytes.

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Funderburg, Nicholas T; Jadlowsky, Julie K; Lederman, Michael M; Feng, Zhimin; Weinberg, Aaron; Sieg, Scott F

2011-10-01

Human β-defensin 3 (hBD-3) activates antigen-presenting cells through Toll-like receptors (TLRs) 1/2. Several TLR1/2 agonists have been identified but little is known about how they might differentially affect cellular activation. We compared the effects of hBD-3 with those of another TLR1/2 agonist, Pam(3) CSK(4) , in human monocytes. Monocytes incubated with hBD-3 or Pam(3) CSK(4) produced interleukin-6 (IL-6), IL-8 and IL-1β, but only Pam(3) CSK(4) induced IL-10. The IL-10 induction by Pam(3) CSK(4) caused down-modulation of the co-stimulatory molecule, CD86, whereas CD86 expression was increased in monocytes exposed to hBD-3. Assessment of signalling pathways linked to IL-10 induction indicated that mitogen-activated protein kinases were activated similarly by hBD-3 or Pam(3) CSK(4) , whereas the non-canonical nuclear factor-κB pathway was only induced by Pam(3) CSK(4) . Our data suggest that the lack of non-canonical nuclear factor-κB signalling by hBD-3 could contribute to the failure of this TLR agonist to induce production of the anti-inflammatory cytokine, IL-10, in human monocytes. © 2011 The Authors. Immunology © 2011 Blackwell Publishing Ltd.

Monocyte-lymphocyte fusion induced by the HIV-1 envelope generates functional heterokaryons with an activated monocyte-like phenotype

International Nuclear Information System (INIS)

Martínez-Méndez, David; Rivera-Toledo, Evelyn; Ortega, Enrique; Licona-Limón, Ileana; Huerta, Leonor

2017-01-01

Enveloped viruses induce cell-cell fusion when infected cells expressing viral envelope proteins interact with target cells, or through the contact of cell-free viral particles with adjoining target cells. CD4"+ T lymphocytes and cells from the monocyte-macrophage lineage express receptors for HIV envelope protein. We have previously reported that lymphoid Jurkat T cells expressing the HIV-1 envelope protein (Env) can fuse with THP-1 monocytic cells, forming heterokaryons with a predominantly myeloid phenotype. This study shows that the expression of monocytic markers in heterokaryons is stable, whereas the expression of lymphoid markers is mostly lost. Like THP-1 cells, heterokaryons exhibited FcγR-dependent phagocytic activity and showed an enhanced expression of the activation marker ICAM-1 upon stimulation with PMA. In addition, heterokaryons showed morphological changes compatible with maturation, and high expression of the differentiation marker CD11b in the absence of differentiation-inducing agents. No morphological change nor increase in CD11b expression were observed when an HIV-fusion inhibitor blocked fusion, or when THP-1 cells were cocultured with Jurkat cells expressing a non-fusogenic Env protein, showing that differentiation was not induced merely by cell-cell interaction but required cell-cell fusion. Inhibition of TLR2/TLR4 signaling by a TIRAP inhibitor greatly reduced the expression of CD11b in heterokaryons. Thus, lymphocyte-monocyte heterokaryons induced by HIV-1 Env are stable and functional, and fusion prompts a phenotype characteristic of activated monocytes via intracellular TLR2/TLR4 signaling. - Highlights: • Jurkat T cells expressing the HIV-1 envelope fuse with THP-1 monocytes. • Heterokaryons display a dominant myeloid phenotype and monocyte function. • Heterokaryons exhibit activation features in the absence of activation agents. • Activation is not due to cell-cell interaction but requires cell-cell fusion. • The

Monocyte-lymphocyte fusion induced by the HIV-1 envelope generates functional heterokaryons with an activated monocyte-like phenotype

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Martínez-Méndez, David; Rivera-Toledo, Evelyn; Ortega, Enrique; Licona-Limón, Ileana; Huerta, Leonor, E-mail: leonorhh@biomedicas.unam.mx

2017-03-01

Enveloped viruses induce cell-cell fusion when infected cells expressing viral envelope proteins interact with target cells, or through the contact of cell-free viral particles with adjoining target cells. CD4{sup +} T lymphocytes and cells from the monocyte-macrophage lineage express receptors for HIV envelope protein. We have previously reported that lymphoid Jurkat T cells expressing the HIV-1 envelope protein (Env) can fuse with THP-1 monocytic cells, forming heterokaryons with a predominantly myeloid phenotype. This study shows that the expression of monocytic markers in heterokaryons is stable, whereas the expression of lymphoid markers is mostly lost. Like THP-1 cells, heterokaryons exhibited FcγR-dependent phagocytic activity and showed an enhanced expression of the activation marker ICAM-1 upon stimulation with PMA. In addition, heterokaryons showed morphological changes compatible with maturation, and high expression of the differentiation marker CD11b in the absence of differentiation-inducing agents. No morphological change nor increase in CD11b expression were observed when an HIV-fusion inhibitor blocked fusion, or when THP-1 cells were cocultured with Jurkat cells expressing a non-fusogenic Env protein, showing that differentiation was not induced merely by cell-cell interaction but required cell-cell fusion. Inhibition of TLR2/TLR4 signaling by a TIRAP inhibitor greatly reduced the expression of CD11b in heterokaryons. Thus, lymphocyte-monocyte heterokaryons induced by HIV-1 Env are stable and functional, and fusion prompts a phenotype characteristic of activated monocytes via intracellular TLR2/TLR4 signaling. - Highlights: • Jurkat T cells expressing the HIV-1 envelope fuse with THP-1 monocytes. • Heterokaryons display a dominant myeloid phenotype and monocyte function. • Heterokaryons exhibit activation features in the absence of activation agents. • Activation is not due to cell-cell interaction but requires cell-cell fusion. • The

Monocyte-Derived Signals Activate Human Natural Killer Cells in Response to Leishmania Parasites

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Messlinger, Helena; Sebald, Heidi; Heger, Lukas; Dudziak, Diana; Bogdan, Christian; Schleicher, Ulrike

2018-01-01

Activated natural killer (NK) cells release interferon (IFN)-γ, which is crucial for the control of intracellular pathogens such as Leishmania. In contrast to experimental murine leishmaniasis, the human NK cell response to Leishmania is still poorly characterized. Here, we investigated the interaction of human blood NK cells with promastigotes of different Leishmania species (Leishmania major, Leishmania mexicana, Leishmania infantum, and Leishmania donovani). When peripheral blood mononuclear cells or purified NK cells and monocytes (all derived from healthy blood donors from Germany without a history of leishmaniasis) were exposed to promastigotes, NK cells showed increased surface expression of the activation marker CD69. The extent of this effect varied depending on the Leishmania species; differences between dermotropic and viscerotropic L. infantum strains were not observed. Upregulation of CD69 required direct contact between monocytes and Leishmania and was partly inhibitable by anti-interleukin (IL)-18. Unexpectedly, IL-18 was undetectable in most of the supernatants (SNs) of monocyte/parasite cocultures. Confocal fluorescence microscopy of non-permeabilized cells revealed that Leishmania-infected monocytes trans-presented IL-18 to NK cells. Native, but not heat-treated SNs of monocyte/Leishmania cocultures also induced CD69 on NK cells, indicating the involvement of a soluble heat-labile factor other than IL-18. A role for the NK cell-activating cytokines IL-1β, IL-2, IL-12, IL-15, IL-21, and IFN-α/β was excluded. The increase of CD69 was not paralleled by NK cell IFN-γ production or enhanced cytotoxicity. However, prior exposure of NK cells to Leishmania parasites synergistically increased their IFN-γ release in response to IL-12, which was dependent on endogenous IL-18. CD1c+ dendritic cells were identified as possible source of Leishmania-induced IL-12. Finally, we observed that direct contact between Leishmania and NK cells reduced the

Monocyte-Derived Signals Activate Human Natural Killer Cells in Response to Leishmania Parasites

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Helena Messlinger

2018-01-01

Full Text Available Activated natural killer (NK cells release interferon (IFN-γ, which is crucial for the control of intracellular pathogens such as Leishmania. In contrast to experimental murine leishmaniasis, the human NK cell response to Leishmania is still poorly characterized. Here, we investigated the interaction of human blood NK cells with promastigotes of different Leishmania species (Leishmania major, Leishmania mexicana, Leishmania infantum, and Leishmania donovani. When peripheral blood mononuclear cells or purified NK cells and monocytes (all derived from healthy blood donors from Germany without a history of leishmaniasis were exposed to promastigotes, NK cells showed increased surface expression of the activation marker CD69. The extent of this effect varied depending on the Leishmania species; differences between dermotropic and viscerotropic L. infantum strains were not observed. Upregulation of CD69 required direct contact between monocytes and Leishmania and was partly inhibitable by anti-interleukin (IL-18. Unexpectedly, IL-18 was undetectable in most of the supernatants (SNs of monocyte/parasite cocultures. Confocal fluorescence microscopy of non-permeabilized cells revealed that Leishmania-infected monocytes trans-presented IL-18 to NK cells. Native, but not heat-treated SNs of monocyte/Leishmania cocultures also induced CD69 on NK cells, indicating the involvement of a soluble heat-labile factor other than IL-18. A role for the NK cell-activating cytokines IL-1β, IL-2, IL-12, IL-15, IL-21, and IFN-α/β was excluded. The increase of CD69 was not paralleled by NK cell IFN-γ production or enhanced cytotoxicity. However, prior exposure of NK cells to Leishmania parasites synergistically increased their IFN-γ release in response to IL-12, which was dependent on endogenous IL-18. CD1c+ dendritic cells were identified as possible source of Leishmania-induced IL-12. Finally, we observed that direct contact between Leishmania and NK cells

A System Dynamics Model to Predict the Human Monocyte Response to Endotoxins

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Enrique Álvarez

2017-08-01

Full Text Available System dynamics is a powerful tool that allows modeling of complex and highly networked systems such as those found in the human immune system. We have developed a model that reproduces how the exposure of human monocytes to lipopolysaccharides (LPSs induces an inflammatory state characterized by high production of tumor necrosis factor alpha (TNFα, which is rapidly modulated to enter into a tolerant state, known as endotoxin tolerance (ET. The model contains two subsystems with a total of six states, seven flows, two auxiliary variables, and 14 parameters that interact through six differential and nine algebraic equations. The parameters were estimated and optimized to obtain a model that fits the experimental data obtained from human monocytes treated with various LPS doses. In contrast to publications on other animal models, stimulation of human monocytes with super-low-dose LPSs did not alter the response to a second LPSs challenge, neither inducing ET, nor enhancing the inflammatory response. Moreover, the model confirms the low production of TNFα and increased levels of C–C motif ligand 2 when monocytes exhibit a tolerant state similar to that of patients with sepsis. At present, the model can help us better understand the ET response and might offer new insights on sepsis diagnostics and prognosis by examining the monocyte response to endotoxins in patients with sepsis.

[Changes of monocyte and monocyte-platelet aggregates in different subgroups of thrombotic events in patients with acute myocardial infarction during PCI].

Science.gov (United States)

Wang, Sheng; Sun, Cuifang; Liao, Wang; Wu, Zhongwei; Wang, Yudai; Huang, Xiuxian; Lu, Sijia; Dong, Xiaoli; Shuai, Fujie; Li, Bin

2017-07-01

Objective To investigate the impact of thrombotic events on the alterations of monocyte and monocyte-platelet aggregates (MPAs) in patients with acute myocardial infarction (AMI) during percutaneous coronary intervention (PCI). Methods Blood was collected before PCI for flow cytometry. Monocyte subsets and MPAs were detected by four-color platform (CDl4-APC, CDl6-PE-Cy7, CD86-PE and CD41-Alexa Fluor R 488). According to the expression of the platelet surface marker CD41, the number of monocyte subsets and MPAs was analyzed using the fluorescent microspheres of absolute counting tube. The Wilcoxon rank sum test and receiver operating characteristic (ROC) curve analysis were performed. Results CD14 + CD16 ++ monocytes in intraprocedural thrombotic events (IPTE) group were significantly fewer than those in non-IPTE group, and the percentage in total mononuclear cells decreased. Compared with non-IPTE group, MPA binding ratio and monocyte subset MPA binding ratio were significantly higher in IPTE group. ROC analysis showed that MPA binding ratio and subgroup MPA binding ratio had a better predictive value for IPTE in patients with AMI. Conclusion The CD14 + CD16 ++ monocytes in IPTE group were significantly fewer than those in the non-IPTE group. MPA binding ratio and MPA binding ratio of monocyte subsets were significantly higher in the IPTE group than in the non-IPTE group, so they have a good predictive value for IPTE in patients with AMI.

Cancer Cell-derived Exosomes Induce Mitogen-activated Protein Kinase-dependent Monocyte Survival by Transport of Functional Receptor Tyrosine Kinases*

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Song, Xiao; Ding, Yanping; Liu, Gang; Yang, Xiao; Zhao, Ruifang; Zhang, Yinlong; Zhao, Xiao; Anderson, Gregory J.; Nie, Guangjun

2016-01-01

Tumor-associated macrophages (TAM) play pivotal roles in cancer initiation and progression. Monocytes, the precursors of TAMs, normally undergo spontaneous apoptosis within 2 days, but can subsist in the inflammatory tumor microenvironment for continuous survival and generation of sufficient TAMs. The mechanisms underlying tumor-driving monocyte survival remain obscure. Here we report that cancer cell-derived exosomes were crucial mediators for monocyte survival in the inflammatory niche. Analysis of the survival-promoting molecules in monocytes revealed that cancer cell-derived exosomes activated Ras and extracellular signal-regulated kinases in the mitogen-activated protein kinase (MAPK) pathway, resulting in the prevention of caspase cleavage. Phosphorylated receptor tyrosine kinases (RTKs), such as phosphorylated epidermal growth factor receptor (EGFR) and human epidermal growth factor receptor 2 (HER-2), were abundantly expressed in cancer cell-derived exosomes. Knock-out of EGFR or/and HER-2, or alternatively, inhibitors against their phosphorylation significantly disturbed the exosome-mediated activation of the MAPK pathway, inhibition of caspase cleavage, and increase in survival rate in monocytes. Moreover, the deprived survival-stimulating activity of exosomes due to null expression of EGFR and HER-2 could be restored by activation of another RTK, insulin receptor. Overall, our study uncovered a mechanism of tumor-associated monocyte survival and demonstrated that cancer cell-derived exosomes can stimulate the MAPK pathway in monocytes through transport of functional RTKs, leading to inactivation of apoptosis-related caspases. This work provides insights into the long sought question on monocyte survival prior to formation of plentiful TAMs in the tumor microenvironment. PMID:26895960

Consequences of gamma-irradiation on inflammatory cytokine regulation in human monocytes/macrophages; Consequences de l`irradiation gamma sur la regulation des cytokines de l`inflammation dans les monocytes/macrophages humains

Energy Technology Data Exchange (ETDEWEB)

Pons, I.; Gras, G.; Dormont, D.

1995-12-31

Inflammation is a frequent radiation-induced damage, especially after therapeutic irradiation. In this study, we have investigated, the inflammatory cytokine regulation after ionizing irradiation of monocytes/macrophages from four donors. Semi-quantitative RT-PCR revealed, after in vitro 24 h-differentiated monocytes irradiation between 5 to 40 Gy, no induction of interleukin-I{beta} (IL I{beta}), interleukin-6 (IL-6) and tumor necrosis factor-{alpha} (TNF-{alpha} mRNA) expression. Moreover, protein quantitation shows no significant increase of post-irradiation secretion. (author). 6 refs.

Plasma L-cystine/L-glutamate imbalance increases tumor necrosis factor-alpha from CD14+ circulating monocytes in patients with advanced cirrhosis.

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Eiji Kakazu

Full Text Available BACKGROUND AND AIMS: The innate immune cells can not normally respond to the pathogen in patients with decompensated cirrhosis. Previous studies reported that antigen-presenting cells take up L-Cystine (L-Cys and secrete substantial amounts of L-Glutamate (L-Glu via the transport system Xc- (4F2hc+xCT, and that this exchange influences the immune responses. The aim of this study is to investigate the influence of the plasma L-Cys/L-Glu imbalance observed in patients with advanced cirrhosis on the function of circulating monocytes. METHODS: We used a serum-free culture medium consistent with the average concentrations of plasma amino acids from patients with advanced cirrhosis (ACM, and examined the function of CD14+ monocytes or THP-1 under ACM that contained 0-300 nmol/mL L-Cys with LPS. In patients with advanced cirrhosis, we actually determined the TNF-alpha and xCT mRNA of monocytes, and evaluated the correlation between the plasma L-Cys/L-Glu ratio and TNF-alpha. RESULTS: The addition of L-Cys significantly increased the production of TNF alpha from monocytes under ACM. Monocytes with LPS and THP-1 expressed xCT and a high level of extracellular L-Cys enhanced L-Cys/L-Glu antiport, and the intracellular GSH/GSSG ratio was decreased. The L-Cys transport was inhibited by excess L-Glu. In patients with advanced cirrhosis (n = 19, the TNF-alpha and xCT mRNA of monocytes were increased according to the Child-Pugh grade. The TNF-alpha mRNA of monocytes was significantly higher in the high L-Cys/L-Glu ratio group than in the low ratio group, and the plasma TNF-alpha was significantly correlated with the L-Cys/L-Glu ratio. CONCLUSIONS: A plasma L-Cys/L-Glu imbalance, which appears in patients with advanced cirrhosis, increased the TNF-alpha from circulating monocytes via increasing the intracellular oxidative stress. These results may reflect the immune abnormality that appears in patients with decompensated cirrhosis.

Chemotactic behavior of deep subsurface bacteria toward carbohydrates, amino acids and a chlorinated alkene

Energy Technology Data Exchange (ETDEWEB)

Lopez de Victoria, G. (Puerto Rico Univ., Rio Piedras (Puerto Rico). Dept. of Biology)

1989-02-01

The chemotactic behavior of deep terrestrial subsurface bacteria toward amino acids, carbohydrates and trichloroethylene was assayed using a modification of the capillary method and bacterial enumeration by acridine orange direct counts. Eleven isolates of bacteria isolated from six different geological formations were investigated. A bimodal response rather than an absolute positive or negative response was observed in most assays. Most of the isolates were positively chemotactic to low concentrations of substrates and were repelled by high concentrations of the same substrate. However, this was not the case for trichloroethylene (TCE) which was mostly an attractant and elicited the highest responses in all the isolates when compared with amino acids and carbohydrates. The movement rates of these isolates in aseptic subsurface sediments in the absence and presence of TCE were also determined using a laboratory model. All of the isolates showed distinct response range, peak, and threshold concentrations when exposed to the same substrates suggesting that they are possibly different species as has been inferred from DNA homology studies. 101 refs., 4 figs., 57 tabs.

Maturation of human dendritic cells by monocyte-conditioned medium is dependent upon trace amounts of lipopolysaccharide inducing tumour necrosis factor alpha

DEFF Research Database (Denmark)

Nersting, Jacob; Svenson, Morten; Andersen, Vagn

2003-01-01

We investigated the ability of monocyte-conditioned medium (MCM), generated by monocytes cultured on plastic-immobilised immunoglobulin, to stimulate maturation of human monocyte-derived dendritic cells (DC). Earlier reports suggest that MCM is a strong inducer of irreversible DC maturation......, whereas we find, that adding a small amount of lipopolysaccharide (LPS) to the MCM-generating cultures is required for the production of a DC-stimulatory MCM. Moreover, compared with addition of LPS directly to the DC cultures, stimulation via MCM cultures increases by several fold the DC...

FC-99 ameliorates sepsis-induced liver dysfunction by modulating monocyte/macrophage differentiation via Let-7a related monocytes apoptosis.

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Zhao, Yarong; Zhu, Haiyan; Wang, Haining; Ding, Liang; Xu, Lizhi; Chen, Dai; Shen, Sunan; Hou, Yayi; Dou, Huan

2018-03-13

The liver is a vital target for sepsis-related injury, leading to inflammatory pathogenesis, multiple organ dysfunction and high mortality rates. Monocyte-derived macrophage transformations are key events in hepatic inflammation. N 1 -[(4-methoxy)methyl]-4-methyl-1,2-benzenediamine (FC-99) previously displayed therapeutic potential on experimental sepsis. However, the underlying mechanism of this protective effect is still not clear. FC-99 treatment attenuated the liver dysfunction in septic mice that was accompanied with reduced numbers of pro-inflammatory Ly6C hi monocytes in the peripheral blood and CD11b + F4/80 lo monocyte-derived macrophages in the liver. These effects were attributed to the FC-99-induced apoptosis of CD11b + cells. In PMA-differentiated THP-1 cells, FC-99 repressed the expression of CD11b, CD14 and caspase3 and resulted in a high proportion of Annexin V + cells. Moreover, let-7a-5p expression was abrogated upon CLP stimulation in vivo , whereas it was restored by FC-99 treatment. TargetScan analysis and luciferase assays indicated that the anti-apoptotic protein BCL-XL was targeted by let-7a-5p. BCL-XL was inhibited by FC-99 in order to induce monocyte apoptosis, leading to the impaired monocyte-to-macrophage differentiation. Murine acute liver failure was generated by caecal ligation puncture surgery after FC-99 administration; Blood samples and liver tissues were collected to determine the monocyte/macrophage subsets and the induction of apoptosis. Human acute monocytic leukemia cell line (THP-1) cells were pretreated with FC-99 followed by phorbol-12-myristate-13-acetate (PMA) stimulation, in order to induce monocyte-to-macrophage differentiation. The target of FC-99 and the mechanistic analyses were conducted by microarrays, qRT-PCR validation, TargetScan algorithms and a luciferase report assay. FC-99 exhibits potential therapeutic effects on CLP-induced liver dysfunction by restoring let-7a-5p levels.

Blood Monocyte Subsets and Selected Cardiovascular Risk Markers in Rheumatoid Arthritis of Short Duration in relation to Disease Activity

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Ewa Klimek

2014-01-01

Full Text Available Objectives. To evaluate blood monocyte subsets and functional monocyte properties in patients with rheumatoid arthritis (RA of short duration in the context of cardiovascular (CV risk and disease activity. Methods. We studied conventional markers of CV risk, intima media thickness (IMT, and blood monocyte subsets in 27 patients aged 41 ± 10 years with RA of short duration (median 12 months and 22 healthy controls. The RA subjects were divided into low (DAS28: 2.6–5.1 and high (DAS28 > 5.1 disease activity. Results. RA patients exhibited increased levels of intermediate (CD14++CD16+ monocytes with decreased CD45RA expression compared to controls, increased counts of classical (CD14++CD16− monocytes, and decreased percentages of nonclassical (CD14+CD16++ monocytes. Patients with high disease activity had lower HLA DR expression on classical monocytes compared to low disease activity patients. There were no differences in monocyte subsets between subjects with DAS > 5.1 and DAS ≤ 5.1. There were no significant intergroup differences in IMT and the majority of classical CV risk factors. Conclusions. Patients with RA of short duration show alteration in peripheral blood monocyte subsets despite the fact that there is no evidence of subclinical atherosclerosis. Disease activity assessed with DAS28 was associated with impaired functional properties but not with a shift in monocyte subpopulations.

Evidence for unfolded protein response activation in monocytes from individuals with alpha-1 antitrypsin deficiency.

LENUS (Irish Health Repository)

Carroll, Tomás P

2010-04-15

The hereditary disorder alpha-1 antitrypsin (AAT) deficiency results from mutations in the SERPINA1 gene and presents with emphysema in young adults and liver disease in childhood. The most common form of AAT deficiency occurs because of the Z mutation, causing the protein to fold aberrantly and accumulate in the endoplasmic reticulum (ER). This leads to ER stress and contributes significantly to the liver disease associated with the condition. In addition to hepatocytes, AAT is also synthesized by monocytes, neutrophils, and epithelial cells. In this study we show for the first time that the unfolded protein response (UPR) is activated in quiescent monocytes from ZZ individuals. Activating transcription factor 4, X-box binding protein 1, and a subset of genes involved in the UPR are increased in monocytes from ZZ compared with MM individuals. This contributes to an inflammatory phenotype with ZZ monocytes exhibiting enhanced cytokine production and activation of the NF-kappaB pathway when compared with MM monocytes. In addition, we demonstrate intracellular accumulation of AAT within the ER of ZZ monocytes. These are the first data showing that Z AAT protein accumulation induces UPR activation in peripheral blood monocytes. These findings change the current paradigm regarding lung inflammation in AAT deficiency, which up until now was derived from the protease-anti-protease hypothesis, but which now must include the exaggerated inflammatory response generated by accumulated aberrantly folded AAT in circulating blood cells.

Phenotypic heterogeneity of peripheral monocytes in healthy dogs.

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Gibbons, Natalie; Goulart, Michelle R; Chang, Yu-Mei; Efstathiou, Konstantinos; Purcell, Robert; Wu, Ying; Peters, Laureen M; Turmaine, Mark; Szladovits, Balazs; Garden, Oliver A

2017-08-01

Monocytes are key cells of the innate immune system. Their phenotypic and functional roles have been investigated in humans, mice and other animals, such as the rat, pig and cow. To date, detailed phenotypic analysis of monocytes has not been undertaken in dogs. Two important surface markers in human monocytes are CD14 and MHC class II (MHC II). By flow cytometry, we demonstrated that canine monocytes can be subdivided into three separate populations: CD14 pos MHC II neg , CD14 pos MHC II pos and CD14 neg MHC II pos . Both light and transmission electron microscopy confirmed the monocytic identity of all three populations. The CD14 pos MHC II neg population could be distinguished on an ultrastructural level by their smaller size, the presence of more numerous, larger granules, and more pseudopodia than both of the other populations. Copyright © 2017 Elsevier B.V. All rights reserved.

Cancer Cell-derived Exosomes Induce Mitogen-activated Protein Kinase-dependent Monocyte Survival by Transport of Functional Receptor Tyrosine Kinases.

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Song, Xiao; Ding, Yanping; Liu, Gang; Yang, Xiao; Zhao, Ruifang; Zhang, Yinlong; Zhao, Xiao; Anderson, Gregory J; Nie, Guangjun

2016-04-15

Tumor-associated macrophages (TAM) play pivotal roles in cancer initiation and progression. Monocytes, the precursors of TAMs, normally undergo spontaneous apoptosis within 2 days, but can subsist in the inflammatory tumor microenvironment for continuous survival and generation of sufficient TAMs. The mechanisms underlying tumor-driving monocyte survival remain obscure. Here we report that cancer cell-derived exosomes were crucial mediators for monocyte survival in the inflammatory niche. Analysis of the survival-promoting molecules in monocytes revealed that cancer cell-derived exosomes activated Ras and extracellular signal-regulated kinases in the mitogen-activated protein kinase (MAPK) pathway, resulting in the prevention of caspase cleavage. Phosphorylated receptor tyrosine kinases (RTKs), such as phosphorylated epidermal growth factor receptor (EGFR) and human epidermal growth factor receptor 2 (HER-2), were abundantly expressed in cancer cell-derived exosomes. Knock-out of EGFR or/and HER-2, or alternatively, inhibitors against their phosphorylation significantly disturbed the exosome-mediated activation of the MAPK pathway, inhibition of caspase cleavage, and increase in survival rate in monocytes. Moreover, the deprived survival-stimulating activity of exosomes due to null expression of EGFR and HER-2 could be restored by activation of another RTK, insulin receptor. Overall, our study uncovered a mechanism of tumor-associated monocyte survival and demonstrated that cancer cell-derived exosomes can stimulate the MAPK pathway in monocytes through transport of functional RTKs, leading to inactivation of apoptosis-related caspases. This work provides insights into the long sought question on monocyte survival prior to formation of plentiful TAMs in the tumor microenvironment. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

Adding exercise to rosuvastatin treatment: influence on C-reactive protein, monocyte toll-like receptor 4 expression, and inflammatory monocyte (CD14+CD16+) population.

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Coen, Paul M; Flynn, Michael G; Markofski, Melissa M; Pence, Brandt D; Hannemann, Robert E

2010-12-01

Statin treatment and exercise training can reduce markers of inflammation when administered separately. The purpose of this study was to determine the effect of rosuvastatin treatment and the addition of exercise training on circulating markers of inflammation including C-reactive protein (CRP), monocyte toll-like receptor 4 (TLR4) expression, and CD14+CD16+ monocyte population size. Thirty-three hypercholesterolemic and physically inactive subjects were randomly assigned to rosuvastatin (R) or rosuvastatin/exercise (RE) groups. A third group of physically active hypercholesterolemic subjects served as a control (AC). The R and RE groups received rosuvastatin treatment (10 mg/d) for 20 weeks. From week 10 to week 20, the RE group also participated in an exercise training program (3d/wk). Measurements were made at baseline (Pre), week 10 (Mid), and week 20 (Post), and included TLR4 expression on CD14+ monocytes and CD14+CD16+ monocyte population size as determined by 3-color flow cytometry. Serum CRP was quantified by enzyme-linked immunosorbent assay. TLR4 expression on CD14+ monocytes was higher in the R group at week 20. When treatment groups (R and RE) were combined, serum CRP was lower across time. Furthermore, serum CRP and inflammatory monocyte population size were lower in the RE group compared with the R group at the Post time point. When all groups (R, RE, and AC) were combined, TLR4 expression was greater on inflammatory monocytes (CD14+CD16+) compared with classic monocytes (CD14+CD16⁻) at all time points. In conclusion, rosuvastatin may influence monocyte inflammatory response by increasing TLR4 expression on circulating monocytes. The addition of exercise training to rosuvastatin treatment further lowered CRP and reduced the size of the inflammatory monocyte population, suggesting an additive anti-inflammatory effect of exercise. Copyright © 2010 Elsevier Inc. All rights reserved.

The monocyte counts to HDL cholesterol ratio in obese and lean patients with polycystic ovary syndrome.

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Usta, Akin; Avci, Eyup; Bulbul, Cagla Bahar; Kadi, Hasan; Adali, Ertan

2018-04-10

Women with polycystic ovary syndrome are more likely to suffer from obesity, insulin resistance, and chronic low-grade inflammation. In fact, the excessive activation of monocytes exacerbates oxidative stress and inflammation. However, high-density lipoprotein cholesterol neutralizes the pro-inflammatory and pro-oxidant effects of monocytes. The aim of this study is to investigate whether monocyte counts to high-density lipoprotein cholesterol ratio can predict the inflammatory condition in patients with polycystic ovary syndrome. In this cross-sectional study, a total of 124 women (61 of them with polycystic ovary syndrome and 63 age-matched healthy volunteers) were included in the study population. Obese polycystic ovary syndrome patients (n = 30) with a body mass index of ≥25 kg/m 2 and lean polycystic ovary syndrome patients (n = 31) with a body mass index of polycystic ovary syndrome were significantly higher than in control subjects (p = 0.0018). Moreover, a regression analysis revealed that body mass index, the homeostasis model assessment of insulin resistance and the high sensitivity C-reactive protein levels were confounding factors that affected the monocyte counts to high density lipoprotein cholesterol values. Additionally, a univariate and multivariate logistic regression analysis demonstrated that the increased monocyte counts to high density lipoprotein cholesterol values were more sensitive than the other known risk factors (such as increased body mass index, homeostasis model assessment of insulin resistance and high sensitive C-reactive protein levels) in the prediction of the inflammation in patients with polycystic ovary syndrome. The present study demonstrated that the monocyte count to high density lipoprotein cholesterol may be a novel and useful predictor of the presence of polycystic ovary syndrome.

Increased C-C chemokine receptor 2 gene expression in monocytes of severe obstructive sleep apnea patients and under intermittent hypoxia.

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Chuang, Li-Pang; Chen, Ning-Hung; Lin, Shih-Wei; Chang, Ying-Ling; Liao, Hsiang-Ruei; Lin, Yu-Sheng; Chao, I-Ju; Lin, Yuling; Pang, Jong-Hwei S

2014-01-01

Obstructive sleep apnea (OSA) is known to be a risk factor of coronary artery disease. The chemotaxis and adhesion of monocytes to the endothelium in the early atherosclerosis is important. This study aimed to investigate the effect of intermittent hypoxia, the hallmark of OSA, on the chemotaxis and adhesion of monocytes. Peripheral blood was sampled from 54 adults enrolled for suspected OSA. RNA was prepared from the isolated monocytes for the analysis of C-C chemokine receptor 2 (CCR2). The effect of intermittent hypoxia on the regulation and function of CCR2 was investigated on THP-1 monocytic cells and monocytes. The mRNA and protein expression levels were investigated by RT/real-time PCR and western blot analysis, respectively. Transwell filter migration assay and cell adhesion assay were performed to study the chemotaxis and adhesion of monocytes. Monocytic CCR2 gene expression was found to be increased in severe OSA patients and higher levels were detected after sleep. Intermittent hypoxia increased the CCR2 expression in THP-1 monocytic cells even in the presence of TNF-α and CRP. Intermittent hypoxia also promoted the MCP-1-mediated chemotaxis and adhesion of monocytes to endothelial cells. Furthermore, inhibitor for p42/44 MAPK or p38 MAPK suppressed the activation of monocytic CCR2 expression by intermittent hypoxia. This is the first study to demonstrate the increase of CCR2 gene expression in monocytes of severe OSA patients. Monocytic CCR2 gene expression can be induced under intermittent hypoxia which contributes to the chemotaxis and adhesion of monocytes.

The Histone Deacetylase Inhibitors MS-275 and SAHA Suppress the p38 Mitogen-Activated Protein Kinase Signaling Pathway and Chemotaxis in Rheumatoid Arthritic Synovial Fibroblastic E11 Cells

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Hai-Shu Lin

2013-11-01

Full Text Available MS-275 (entinostat and SAHA (vorinostat, two histone deacetylase (HDAC inhibitors currently in oncological trials, have displayed potent anti-rheumatic activities in rodent models of rheumatoid arthritis (RA. To further elucidate their anti-inflammatory mechanisms, the impact of MS-275 and SAHA on the p38 mitogen-activated protein kinase (MAPK signaling pathway and chemotaxis was assessed in human rheumatoid arthritic synovial fibroblastic E11 cells. MS-275 and SAHA significantly suppressed the expression of p38α  MAPK, but induced the expression of MAPK phosphatase-1 (MKP-1, an endogenous suppressor of p38α  in E11 cells. At the same time, the association between p38α and MKP-1 was up-regulated and consequently, the activation (phosphorylation of p38α  was inhibited. Moreover, MS-275 and SAHA suppressed granulocyte chemotactic protein-2 (GCP-2, monocyte chemotactic protein-2 (MCP-2 and macrophage migration inhibitory factor (MIF in E11 cells in a concentration-dependent manner. Subsequently, E11-driven migration of THP-1 and U937 monocytes was inhibited. In summary, suppression of the p38 MAPK signaling pathway and chemotaxis appear to be important anti-rheumatic mechanisms of action of these HDAC inhibitors.

The effects of exogenous fatty acids and niacin on human monocyte-macrophage plasticity.

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Montserrat-de la Paz, Sergio; Rodriguez, Dolores; Cardelo, Magdalena P; Naranjo, Maria C; Bermudez, Beatriz; Abia, Rocio; Muriana, Francisco J G; Lopez, Sergio

2017-08-01

Macrophage plasticity allows adapting to different environments, having a dual activity in inflammatory-related diseases. Our hypothesis is that the type of dietary fatty acids into human postprandial triglyceride-rich lipoproteins (TRLs), alone or in combination with niacin (vitamin B3), could modulate the plasticity of monocytes-macrophages. We isolated TRLs at the postprandial peak from blood samples of healthy volunteers after the ingestion of a meal rich in saturated fatty acids (SFAs), monounsaturated fatty acids (MUFAs) or MUFAs plus omega-3 long-chain polyunsaturated fatty acids (LCPUFAs). Autologous monocytes isolated at fasting were first induced to differentiate into naïve macrophages. We observed that postprandial TRL-MUFAs, particularly in combination with niacin, enhance competence to monocytes to differentiate and polarise into M2 macrophages. Postprandial TRL-SFAs made polarised macrophages prone to an M1 phenotype. In contrast to dietary SFAs, dietary MUFAs in the meals plus immediate-release niacin primed circulating monocytes for a reduced postprandial pro-inflammatory profile. Our study underlines a role of postprandial TRLs as a metabolic entity in regulating the plasticity of the monocyte-macrophage lineage and also brings an understanding of the mechanisms by which dietary fatty acids are environmental factors fostering the innate immune responsiveness in humans. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The effect of metformin on monocyte secretory function in simvastatin-treated patients with impaired fasting glucose.

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Krysiak, Robert; Okopien, Bogusław

2013-01-01

This study was designed to investigate whether metformin affects monocyte secretory function in patients with impaired fasting glucose receiving chronic statin therapy. The study included 48 patients with impaired fasting glucose treated for at least three months with simvastatin (40 mg daily). These patients were randomized to either metformin (3 g daily) or placebo, which was administered together with simvastatin for 90 days. Plasma lipids, glucose homeostasis markers, monocyte cytokine release and plasma C-reactive protein levels were determined before randomization and at the end of the treatment. Compared to placebo, metformin reduced monocyte release of tumor necrosis factor-α, interleukin-1β, interleukin-6, monocyte chemoattractant protein-1 and interleukin-8, as well as decreased plasma C-reactive protein levels, which were accompanied by an improvement in insulin sensitivity. The obtained results suggest that metformin may inhibit monocyte secretory function and reduce systemic inflammation in statin-treated patients with prediabetes. Impaired fasting glucose patients with high cardiovascular risk may receive the greatest benefits from concomitant treatment with a statin and metformin. Copyright © 2013 Elsevier Inc. All rights reserved.

Filarial excretory-secretory products induce human monocytes to produce lymphangiogenic mediators.

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Tiffany Weinkopff

2014-07-01

Full Text Available The nematodes Wuchereria bancrofti and Brugia spp. infect over 120 million people worldwide, causing lymphedema, elephantiasis and hydrocele, collectively known as lymphatic filariasis. Most infected individuals appear to be asymptomatic, but many exhibit sub-clinical manifestations including the lymphangiectasia that likely contributes to the development of lymphedema and elephantiasis. As adult worm excretory-secretory products (ES do not directly activate lymphatic endothelial cells (LEC, we investigated the role of monocyte/macrophage-derived soluble factors in the development of filarial lymphatic pathology. We analyzed the production of IL-8, IL-6 and VEGF-A by peripheral blood mononuclear cells (PBMC from naïve donors following stimulation with filarial ES products. ES-stimulated PBMCs produced significantly more IL-8, IL-6 and VEGF-A compared to cells cultured in medium alone; CD14(+ monocytes appear to be the primary producers of IL-8 and VEGF-A, but not IL-6. Furthermore, IL-8, IL-6 and VEGF-A induced in vitro tubule formation in LEC Matrigel cultures. Matrigel plugs supplemented with IL-8, IL-6, VEGF-A, or with supernatants from ES-stimulated PBMCs and implanted in vivo stimulated lymphangiogenesis. Collectively, these data support the hypothesis that monocytes/macrophages exposed to filarial ES products may modulate lymphatic function through the secretion of soluble factors that stimulate the vessel growth associated with the pathogenesis of filarial disease.

A matrix of cholesterol crystals, but not cholesterol alone, primes human monocytes/macrophages for excessive endotoxin-induced production of tumor necrosis factor-alpha. Role in atherosclerotic inflammation?

DEFF Research Database (Denmark)

Bendtzen, Klaus; Christensen, Ole; Nielsen, Claus Henrik

2014-01-01

When exposed to small amounts of bacterial endotoxin, matrices of cholesterol crystals, but not cholesterol itself, primed human monocytes/macrophages to a highly augmented (>10-fold) production of inflammatory tumor necrosis factor-α. Priming also sensitized the cells, as 10- to 100-fold lower...

Protein energy malnutrition increases arginase activity in monocytes and macrophages.

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Corware, Karina; Yardley, Vanessa; Mack, Christopher; Schuster, Steffen; Al-Hassi, Hafid; Herath, Shanthi; Bergin, Philip; Modolell, Manuel; Munder, Markus; Müller, Ingrid; Kropf, Pascale

2014-01-01

Protein energy malnutrition is commonly associated with immune dysfunctions and is a major factor in susceptibility to infectious diseases. In this study, we evaluated the impact of protein energy malnutrition on the capacity of monocytes and macrophages to upregulate arginase, an enzyme associated with immunosuppression and increased pathogen replication. Our results show that monocytes and macrophages are significantly increased in the bone marrow and blood of mice fed on a protein low diet. No alteration in the capacity of bone marrow derived macrophages isolated from malnourished mice to phagocytose particles, to produce the microbicidal molecule nitric oxide and to kill intracellular Leishmania parasites was detected. However, macrophages and monocytes from malnourished mice express significantly more arginase both in vitro and in vivo. Using an experimental model of visceral leishmaniasis, we show that following protein energy malnutrition, the increased parasite burden measured in the spleen of these mice coincided with increased arginase activity and that macrophages provide a more permissive environment for parasite growth. Taken together, these results identify a novel mechanism in protein energy malnutrition that might contributes to increased susceptibility to infectious diseases by upregulating arginase activity in myeloid cells.

Macrolactone Nuiapolide, Isolated from a Hawaiian Marine Cyanobacterium, Exhibits Anti-Chemotactic Activity.

Science.gov (United States)

Mori, Shogo; Williams, Howard; Cagle, Davey; Karanovich, Kristopher; Horgen, F David; Smith, Roger; Watanabe, Coran M H

2015-10-09

A new bioactive macrolactone, nuiapolide (1) was identified from a marine cyanobacterium collected off the coast of Niihau, near Lehua Rock. The natural product exhibits anti-chemotactic activity at concentrations as low as 1.3 μM against Jurkat cells, cancerous T lymphocytes, and induces a G2/M phase cell cycle shift. Structural characterization of the natural product revealed the compound to be a 40-membered macrolactone with nine hydroxyl functional groups and a rare tert-butyl carbinol residue.

Macrolactone Nuiapolide, Isolated from a Hawaiian Marine Cyanobacterium, Exhibits Anti-Chemotactic Activity

OpenAIRE

Mori, Shogo; Williams, Howard; Cagle, Davey; Karanovich, Kristopher; Horgen, F. David; Smith, Roger; Watanabe, Coran M. H.

2015-01-01

A new bioactive macrolactone, nuiapolide (1) was identified from a marine cyanobacterium collected off the coast of Niihau, near Lehua Rock. The natural product exhibits anti-chemotactic activity at concentrations as low as 1.3 μM against Jurkat cells, cancerous T lymphocytes, and induces a G2/M phase cell cycle shift. Structural characterization of the natural product revealed the compound to be a 40-membered macrolactone with nine hydroxyl functional groups and a rare tert-butyl carbinol re...

Macrolactone Nuiapolide, Isolated from a Hawaiian Marine Cyanobacterium, Exhibits Anti-Chemotactic Activity

Directory of Open Access Journals (Sweden)

Shogo Mori

2015-10-01

Full Text Available A new bioactive macrolactone, nuiapolide (1 was identified from a marine cyanobacterium collected off the coast of Niihau, near Lehua Rock. The natural product exhibits anti-chemotactic activity at concentrations as low as 1.3 μM against Jurkat cells, cancerous T lymphocytes, and induces a G2/M phase cell cycle shift. Structural characterization of the natural product revealed the compound to be a 40-membered macrolactone with nine hydroxyl functional groups and a rare tert-butyl carbinol residue.

Molecular mechanisms that underlie the dynamic adaptation of innate monocyte memory to varying stimulant strength of TLR ligands

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Ruoxi Yuan

2016-11-01

Full Text Available In adaptation to rising stimulant strength, innate monocytes can be dynamically programmed to preferentially express either pro- or anti-inflammatory mediators. Such dynamic innate adaptation or programming may bear profound relevance in host health and disease. However, molecular mechanisms that govern innate adaptation to varying strength of stimulants are not well understood. Using lipopolysaccharide (LPS, the model stimulant of Toll-Like-Receptor 4 (TLR4, we reported that the expressions of pro-inflammatory mediators are preferentially sustained in monocytes adapted by lower doses of LPS, and suppressed/tolerized in monocytes adapted by higher doses of LPS. Mechanistically, monocytes adapted by super-low dose LPS exhibited higher levels of transcription factor IRF5 and reduced levels of transcriptional modulator BLIMP-1. Intriguingly, the inflammatory monocyte adaptation by super-low dose LPS is dependent upon TRAM/TRIF but not MyD88. Similar to LPS, we also observed biphasic inflammatory adaptation and tolerance in monocytes challenged with varying dosages of TLR7 agonist. In sharp contrast, rising doses of TLR3 agonist preferentially caused inflammatory adaptation without inducing tolerance. At the molecular level, the differential regulation of IRF5 and Blimp-1 coincides with unique monocyte adaptation dynamics by TLR4/7 and TLR3 agonists. Our study provides novel clue toward the understanding of monocyte adaptation and memory toward distinct TLR ligands.

Vascular endothelial growth factor (VEGF and monocyte chemoattractant protein (MCP-1 levels unaltered in symptomatic atherosclerotic carotid plaque patients from North India

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Dheeraj eKhurana

2013-04-01

Full Text Available We aimed to identify the role of vascular endothelial growth factor(VEGF and monocyte chemoattractant protein(MCP-1 as a serum biomarker of symptomatic carotid atherosclerotic plaque in North Indian population. Individuals with symptomatic carotid atherosclerotic plaque have high risk of ischemic stroke. Previous studies from western countries have shown an association between VEGF and MCP-1 levels and the incidence of ischemic stroke. In this study, venous blood from 110 human subjects was collected, 57 blood samples of which were obtained from patients with carotid plaques, 38 neurological controls without carotid plaques and another 15 healthy controls who had no history of serious illness. Serum VEGF and MCP-1 levels were measured using commercially available enzyme-linked immunosorbent assay(ELISA. We also correlated the data clinically and carried out risk factor analysis based on the detailed questionnaire obtained from each patient. For risk factor analysis, a total of 70 symptomatic carotid plaque cases and equal number of age and sex matched healthy controls were analyzed. We found that serum VEGF levels in carotid plaque patients did not show any significant change when compared to either of the controls. Similarly, there was no significant upregulation of monocyte chemoattractant protein-1 in the serum of these patients. The risk factor analysis revealed that hypertension, diabetes, and physical inactivity were the main correlates of carotid atherosclerosis(p<0.05. Prevalence of patients was higher residing in urban areas as compared to rural region. We also found that patients coming from mountaineer region were relatively less vulnerable to cerebral atherosclerosis as compared to the ones residing at plain region. We conclude that the pathogenesis of carotid plaques may progress independent of these inflammatory molecules. In parallel, risk factor analysis indicates hypertension, diabetes and sedentary lifestyle as the most

Monocyte enrichment from leukapheresis products by using the Elutra cell separator.

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Kim, Sinyoung; Kim, Hyun Ok; Baek, Eun-Jung; Choi, Youjeong; Kim, Han-Soo; Lee, Min-Geul

2007-12-01

Dendritic cells (DCs), used in clinical trials for cancer immunotherapy, require processing on an expanded scale to conform to current good manufacturing practice guidelines. This study evaluated a large-scale monocyte enrichment procedure with a commercially available cell separator (Elutra, Gambro BCT) and analyzed the capacity of enriched monocytes to differentiate into DCs. Mononuclear cells were collected in two patients with malignant melanoma and seven healthy donors by leukapheresis. Continuous-counterflow elutriation with the Elutra was performed to enrich and purify monocytes from leukapheresis products. Purity and recovery of enriched monocytes were analyzed by flow cytometry. DCs were generated from the elutriated monocytes and characterized by phenotypic surface marker and stimulatory capacity in an allogeneic mixed lymphocyte reaction. In the leukapheresis products, the total MNC count was 7.3 x 10(9) +/- 0.7 x 10(9) and the mean percentage of CD14+ monocytes was 16.5 +/- 3.8 percent, which increased to 68.9 +/- 7.4 percent after elutriation with the Elutra. The mean monocyte recovery was 94.3 percent. Elutriated monocytes were successfully cultured into phenotypically and functionally mature DCs. These results indicate that the Elutra cell separator allows for fast and easy enrichment of monocytes within a closed system. Furthermore, these monocytes can be differentiated into functionally mature DCs. Compared to plastic adherence and immunomagnetic selection methods, the elutriation procedure is inexpensive, efficient, and very effective.

Inhibition of nuclear factor of activated T-cells (NFAT suppresses accelerated atherosclerosis in diabetic mice.

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Anna V Zetterqvist

Full Text Available OBJECTIVE OF THE STUDY: Diabetic patients have a much more widespread and aggressive form of atherosclerosis and therefore, higher risk for myocardial infarction, peripheral vascular disease and stroke, but the molecular mechanisms leading to accelerated damage are still unclear. Recently, we showed that hyperglycemia activates the transcription factor NFAT in the arterial wall, inducing the expression of the pro-atherosclerotic protein osteopontin. Here we investigate whether NFAT activation may be a link between diabetes and atherogenesis. METHODOLOGY AND PRINCIPAL FINDINGS: Streptozotocin (STZ-induced diabetes in apolipoprotein E(-/- mice resulted in 2.2 fold increased aortic atherosclerosis and enhanced pro-inflammatory burden, as evidenced by elevated blood monocytes, endothelial activation- and inflammatory markers in aorta, and pro-inflammatory cytokines in plasma. In vivo treatment with the NFAT blocker A-285222 for 4 weeks completely inhibited the diabetes-induced aggravation of atherosclerosis, having no effect in non-diabetic mice. STZ-treated mice exhibited hyperglycemia and higher plasma cholesterol and triglycerides, but these were unaffected by A-285222. NFAT-dependent transcriptional activity was examined in aorta, spleen, thymus, brain, heart, liver and kidney, but only augmented in the aorta of diabetic mice. A-285222 completely blocked this diabetes-driven NFAT activation, but had no impact on the other organs or on splenocyte proliferation or cytokine secretion, ruling out systemic immunosuppression as the mechanism behind reduced atherosclerosis. Instead, NFAT inhibition effectively reduced IL-6, osteopontin, monocyte chemotactic protein 1, intercellular adhesion molecule 1, CD68 and tissue factor expression in the arterial wall and lowered plasma IL-6 in diabetic mice. CONCLUSIONS: Targeting NFAT signaling may be a novel and attractive approach for the treatment of diabetic macrovascular complications.

Distinct functional programming of human fetal and adult monocytes.

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Krow-Lucal, Elisabeth R; Kim, Charles C; Burt, Trevor D; McCune, Joseph M

2014-03-20

Preterm birth affects 1 out of 9 infants in the United States and is the leading cause of long-term neurologic handicap and infant mortality, accounting for 35% of all infant deaths in 2008. Although cytokines including interferon-γ (IFN-γ), interleukin-10 (IL-10), IL-6, and IL-1 are produced in response to in utero infection and are strongly associated with preterm labor, little is known about how human fetal immune cells respond to these cytokines. We demonstrate that fetal and adult CD14(+)CD16(-) classical monocytes are distinct in terms of basal transcriptional profiles and in phosphorylation of signal transducers and activators of transcription (STATs) in response to cytokines. Fetal monocytes phosphorylate canonical and noncanonical STATs and respond more strongly to IFN-γ, IL-6, and IL-4 than adult monocytes. We demonstrate a higher ratio of SOCS3 to IL-6 receptor in adult monocytes than in fetal monocytes, potentially explaining differences in STAT phosphorylation. Additionally, IFN-γ signaling results in upregulation of antigen presentation and costimulatory machinery in adult, but not fetal, monocytes. These findings represent the first evidence that primary human fetal and adult monocytes are functionally distinct, potentially explaining how these cells respond differentially to cytokines implicated in development, in utero infections, and the pathogenesis of preterm labor.

Macrophage Activation Mechanisms in Human Monocytic Cell Line-derived Macrophages.

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Sumiya, Yu; Ishikawa, Mami; Inoue, Takahiro; Inui, Toshio; Kuchiike, Daisuke; Kubo, Kentaro; Uto, Yoshihiro; Nishikata, Takahito

2015-08-01

Although the mechanisms of macrophage activation are important for cancer immunotherapy, they are poorly understood. Recently, easy and robust assay systems for assessing the macrophage-activating factor (MAF) using monocytic cell line-derived macrophages were established. Gene-expression profiles of U937- and THP-1-derived macrophages were compared using gene expression microarray analysis and their responses against several MAFs were examined by in vitro experiments. Activated states of these macrophages could not be assigned to a specific sub-type but showed, however, different unique characteristics. The unique of monocytic cell line-derived macrophages could provide clues to understand the activation mechanism of macrophages and, therefore, help to develop effective cancer immunotherapy with MAFs. Copyright© 2015 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

Monocytes/Macrophages Control Resolution of Transient Inflammatory Pain

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Willemen, Hanneke L. D. M.; Eijkelkamp, Niels; Carbajal, Anibal Garza; Wang, Huijing; Mack, Matthias; Zijlstra, Jitske; Heijnen, Cobi J.; Kavelaars, Annemieke

2014-01-01

Insights into mechanisms governing resolution of inflammatory pain are of great importance for many chronic pain–associated diseases. Here we investigate the role of macrophages/monocytes and the anti-inflammatory cytokine interleukin-10 (IL-10) in the resolution of transient inflammatory pain. Depletion of mice from peripheral monocytes/macrophages delayed resolution of intraplantar IL-1β- and carrageenan-induced inflammatory hyperalgesia from 1 to 3 days to >1 week. Intrathecal administration of a neutralizing IL-10 antibody also markedly delayed resolution of IL-1β- and carrageenan-induced inflammatory hyperalgesia. Recently, we showed that IL-1β- and carrageenan-induced hyperalgesia is significantly prolonged in LysM-GRK2+/− mice, which have reduced levels of G-protein-coupled receptor kinase 2 (GRK2) in LysM+ myeloid cells. Here we show that adoptive transfer of wild-type, but not of GRK2+/−, bone marrow-derived monocytes normalizes the resolution of IL-1β-induced hyperalgesia in LysM-GRK2+/− mice. Adoptive transfer of IL-10−/− bone marrow-derived monocytes failed to normalize the duration of IL-1β-induced hyperalgesia in LysM-GRK2+/− mice. Mechanistically, we show that GRK2+/− macrophages produce less IL-10 in vitro. In addition, intrathecal IL-10 administration attenuated IL-1β-induced hyperalgesia in LysM-GRK2+/− mice, whereas it had no effect in wild-type mice. Our data uncover a key role for monocytes/macrophages in promoting resolution of inflammatory hyperalgesia via a mechanism dependent on IL-10 signaling in dorsal root ganglia. Perspective We show that IL-10-producing monocytes/macrophages promote resolution of transient inflammatory hyperalgesia. Additionally, we show that reduced monocyte/macrophage GRK2 impairs resolution of hyperalgesia and reduces IL-10 production. We propose that low GRK2 expression and/or impaired IL-10 production by monocytes/macrophages represent peripheral biomarkers for the risk of developing

Platelet density per monocyte predicts adverse events in patients after percutaneous coronary intervention.

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Rutten, Bert; Roest, Mark; McClellan, Elizabeth A; Sels, Jan W; Stubbs, Andrew; Jukema, J Wouter; Doevendans, Pieter A; Waltenberger, Johannes; van Zonneveld, Anton-Jan; Pasterkamp, Gerard; De Groot, Philip G; Hoefer, Imo E

2016-01-01

Monocyte recruitment to damaged endothelium is enhanced by platelet binding to monocytes and contributes to vascular repair. Therefore, we studied whether the number of platelets per monocyte affects the recurrence of adverse events in patients after percutaneous coronary intervention (PCI). Platelet-monocytes complexes with high and low median fluorescence intensities (MFI) of the platelet marker CD42b were isolated using cell sorting. Microscopic analysis revealed that a high platelet marker MFI on monocytes corresponded with a high platelet density per monocyte while a low platelet marker MFI corresponded with a low platelet density per monocyte (3.4 ± 0.7 vs 1.4 ± 0.1 platelets per monocyte, P=0.01). Using real-time video microscopy, we observed increased recruitment of high platelet density monocytes to endothelial cells as compared with low platelet density monocytes (P=0.01). Next, we classified PCI scheduled patients (N=263) into groups with high, medium and low platelet densities per monocyte and assessed the recurrence of adverse events. After multivariate adjustment for potential confounders, we observed a 2.5-fold reduction in the recurrence of adverse events in patients with a high platelet density per monocyte as compared with a low platelet density per monocyte [hazard ratio=0.4 (95% confidence interval, 0.2-0.8), P=0.01]. We show that a high platelet density per monocyte increases monocyte recruitment to endothelial cells and predicts a reduction in the recurrence of adverse events in patients after PCI. These findings may imply that a high platelet density per monocyte protects against recurrence of adverse events.

MONOCYTES AND MACROPHAGES IN PREGNANCY AND PREECLAMPSIA

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Marijke M Faas

2014-06-01

Full Text Available Preeclampsia is an important complication in pregnancy, characterized byhypertension and proteinuria in the second half of pregnancy. Generalizedactivation of the inflammatory response is thought to play a role in thepathogenesis of preeclampsia. Monocytes may play a central role in thisinflammatory response. Monocytes are short lived cells, that mature in thecirculation and invade into tissues upon an inflammatory stimulus anddevelop into macrophages. Macrophages are abundantly present in theendometrium and play a role in implantation and placentation in normalpregnancy. In preeclampsia, these macrophages appear to be present in largernumbers and are also activated. In the present review we focused on the roleof monocytes and macrophages in the pathophysiology of preeclampsia.

Monocyte-derived dendritic cells are essential for CD8+ T cell activation and anti-tumor responses after local immunotherapy

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Sabine eKuhn

2015-11-01

Full Text Available Tumors harbor several populations of dendritic cells with the ability to prime tumor-specific T cells. However, these T cells mostly fail to differentiate into armed effectors and are unable to control tumor growth. We have previously shown that treatment with immunostimulatory agents at the tumor site can activate anti-tumor immune responses, and is associated with the appearance of a population of monocyte-derived dendritic cells in the tumor and tumor-draining lymph node. Here we use dendritic cell or monocyte depletion and monocyte transfer to show that these monocyte-derived dendritic cells are critical to the activation of anti-tumor immune responses. Treatment with the immunostimulatory agents Monosodium Urate crystals and Mycobacterium smegmatis induced the accumulation of monocytes in the draining lymph node, their upregulation of CD11c and MHCII, and expression of iNOS, TNFα and IL12p40. Blocking monocyte entry into the lymph node and tumor through neutralization of the chemokine CCL2 or inhibition of Colony Stimulating Factor-1 receptor signaling prevented the generation of monocyte-derived dendritic cells, the infiltration of tumor-specific T cells into the tumor, and anti-tumor responses. In a reciprocal fashion, monocytes transferred into mice depleted of CD11c+ cells were sufficient to rescue CD8+ T cell priming in lymph node and delay tumor growth. Thus monocytes exposed to the appropriate conditions become powerful activators of tumor-specific CD8+ T cells and anti-tumor immunity.

CD14CD16 Monocyte Subset Levels in Heart Failure Patients

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Chiara Barisione

2010-01-01

Full Text Available Our aim was to define the distribution of monocyte subsets in a cohort of congestive heart failure (CHF patients, to verify whether increased severity of CHF is linked to the expansion of specific monocyte subsets, and finally to investigate the relationship between monocyte subset relative frequencies, laboratory parameters of inflammation, and monocyte ACE expression.

IκK-16 decreases miRNA-155 expression and attenuates the human monocyte inflammatory response.

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Norman James Galbraith

Full Text Available Excessive inflammatory responses in the surgical patient may result in cellular hypo-responsiveness, which is associated with an increased risk of secondary infection and death. microRNAs (miRNAs, such as miR-155, are powerful regulators of inflammatory signalling pathways including nuclear factor κB (NFκB. Our objective was to determine the effect of IκK-16, a selective blocker of inhibitor of kappa-B kinase (IκK, on miRNA expression and the monocyte inflammatory response. In a model of endotoxin tolerance using primary human monocytes, impaired monocytes had decreased p65 expression with suppressed TNF-α and IL-10 production (P < 0.05. miR-155 and miR-138 levels were significantly upregulated at 17 h in the impaired monocyte (P < 0.05. Notably, IκK-16 decreased miR-155 expression with a corresponding dose-dependent decrease in TNF-α and IL-10 production (P < 0.05, and impaired monocyte function was associated with increased miR-155 and miR-138 expression. In the context of IκK-16 inhibition, miR-155 mimics increased TNF-α production, while miR-155 antagomirs decreased both TNF-α and IL-10 production. These data demonstrate that IκK-16 treatment attenuates the monocyte inflammatory response, which may occur through a miR-155-mediated mechanism, and that IκK-16 is a promising approach to limit the magnitude of an excessive innate inflammatory response to LPS.

Transcriptional profiling of human monocytes identifies the inhibitory receptor CD300a as regulator of transendothelial migration.

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Sharang Ghavampour

Full Text Available Local inflammatory responses are characterized by the recruitment of circulating leukocytes from the blood to sites of inflammation, a process requiring the directed migration of leukocytes across the vessel wall and hence a penetration of the endothelial lining. To identify underlying signalling events and novel factors involved in these processes we screened for genes differentially expressed in human monocytes following their adhesion to and passage through an endothelial monolayer. Functional annotation clustering of the genes identified revealed an overrepresentation of those associated with inflammation/immune response, in particular early monocyte to macrophage differentiation. Among the gene products so far not implicated in monocyte transendothelial migration was the inhibitory immune receptor CD300a. CD300a mRNA and protein levels were upregulated following transmigration and engagement of the receptor by anti-CD300a antibodies markedly reduced monocyte transendothelial migration. In contrast, siRNA mediated downregulation of CD300a in human monocytes increased their rate of migration. CD300a colocalized and cosedimented with actin filaments and, when activated, caused F-actin cytoskeleton alterations. Thus, monocyte transendothelial migration is accompanied by an elevation of CD300a which serves an inhibitory function possibly required for termination of the actual transmigration.

Differential induction from X-irradiated human peripheral blood monocytes to dendritic cells

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Yoshino, Hironori; Takahashi, Kenji; Monzen, Satoru; Kashiwakura, Ikuo

2008-01-01

Dendritic cells (DCs) are a type of antigen-presenting cell which plays an essential role in the immune system. To clarify the influences of ionizing radiation on the differentiation to DCs, we focused on human peripheral blood monocytes and investigated whether X-irradiated monocytes can differentiate into DCs. The non-irradiated monocytes and 5 Gy-irradiated monocytes were induced into immature DCs (iDCs) and mature DCs (mDCs) with appropriate cytokine stimulation, and the induced cells from each monocyte expressed each DC-expressing surface antigen such as CD40, CD86 and HLA-DR. However, the expression levels of CD40 and CD86 on the iDCs derived from the 5 Gy-irradiated monocytes were higher than those of iDCs derived from non-irradiated monocytes. Furthermore, the mDCs derived from 5 Gy-irradiated monocytes had significantly less ability to stimulate allogeneic T cells in comparison to the mDCs derived from non-irradiated monocytes. There were no significant differences in the phagocytotic activity of the iDCs and cytokines detected in the supernatants conditioned by the DCs from the non-irradiated and irradiated monocytes. These results suggest that human monocytes which are exposed to ionizing radiation can thus differentiate into DCs, but there is a tendency that X-irradiation leads to an impairment of the function of DCs. (author)

Proangiogenic hematopoietic cells of monocytic origin: roles in vascular regeneration and pathogenic processes of systemic sclerosis.

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Yamaguchi, Yukie; Kuwana, Masataka

2013-02-01

New blood vessel formation is critical, not only for organ development and tissue regeneration, but also for various pathologic processes, such as tumor development and vasculopathy. The maintenance of the postnatal vascular system requires constant remodeling, which occurs through angiogenesis, vasculogenesis, and arteriogenesis. Vasculogenesis is mediated by the de novo differentiation of mature endothelial cells from endothelial progenitor cells (EPCs). Early studies provided evidence that bone marrow-derived CD14⁺ monocytes can serve as a subset of EPCs because of their expression of endothelial markers and ability to promote neovascularization in vitro and in vivo. However, the current consensus is that monocytic cells do not give rise to endothelial cells in vivo, but function as support cells, by promoting vascular formation and repair through their immediate recruitment to the site of vascular injury, secretion of proangiogenic factors, and differentiation into mural cells. These monocytes that function in a supporting role in vascular repair are now termed monocytic pro-angiogenic hematopoietic cells (PHCs). Systemic sclerosis (SSc) is a multisystem connective tissue disease characterized by excessive fibrosis and microvasculopathy, along with poor vascular formation and repair. We recently showed that in patients with SSc, circulating monocytic PHCs increase dramatically and have enhanced angiogenic potency. These effects may be induced in response to defective vascular repair machinery. Since CD14⁺ monocytes can also differentiate into fibroblast-like cells that produce extracellular matrix proteins, here we propose a new hypothesis that aberrant monocytic PHCs, once mobilized into circulation, may also contribute to the fibrotic process of SSc.

Lactic acid delays the inflammatory response of human monocytes

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Peter, Katrin, E-mail: katrin.peter@ukr.de [Department of Internal Medicine III, University Hospital Regensburg, Franz-Josef-Strauß-Allee 11, 93053 Regensburg (Germany); Rehli, Michael, E-mail: michael.rehli@ukr.de [Department of Internal Medicine III, University Hospital Regensburg, Franz-Josef-Strauß-Allee 11, 93053 Regensburg (Germany); RCI Regensburg Center for Interventional Immunology, University Hospital Regensburg, Franz-Josef-Strauß-Allee 11, 93053 Regensburg (Germany); Singer, Katrin, E-mail: katrin.singer@ukr.de [Department of Internal Medicine III, University Hospital Regensburg, Franz-Josef-Strauß-Allee 11, 93053 Regensburg (Germany); Renner-Sattler, Kathrin, E-mail: kathrin.renner-sattler@ukr.de [Department of Internal Medicine III, University Hospital Regensburg, Franz-Josef-Strauß-Allee 11, 93053 Regensburg (Germany); Kreutz, Marina, E-mail: marina.kreutz@ukr.de [Department of Internal Medicine III, University Hospital Regensburg, Franz-Josef-Strauß-Allee 11, 93053 Regensburg (Germany); RCI Regensburg Center for Interventional Immunology, University Hospital Regensburg, Franz-Josef-Strauß-Allee 11, 93053 Regensburg (Germany)

2015-02-13

Lactic acid (LA) accumulates under inflammatory conditions, e.g. in wounds or tumors, and influences local immune cell functions. We previously noted inhibitory effects of LA on glycolysis and TNF secretion of human LPS-stimulated monocytes. Here, we globally analyze the influence of LA on gene expression during monocyte activation. To separate LA-specific from lactate- or pH-effects, monocytes were treated for one or four hours with LPS in the presence of physiological concentrations of LA, sodium lactate (NaL) or acidic pH. Analyses of global gene expression profiles revealed striking effects of LA during the early stimulation phase. Up-regulation of most LPS-induced genes was significantly delayed in the presence of LA, while this inhibitory effect was attenuated in acidified samples and not detected after incubation with NaL. LA targets included genes encoding for important monocyte effector proteins like cytokines (e.g. TNF and IL-23) or chemokines (e.g. CCL2 and CCL7). LA effects were validated for several targets by quantitative RT-PCR and/or ELISA. Further analysis of LPS-signaling pathways revealed that LA delayed the phosphorylation of protein kinase B (AKT) as well as the degradation of IκBα. Consistently, the LPS-induced nuclear accumulation of NFκB was also diminished in response to LA. These results indicate that the broad effect of LA on gene expression and function of human monocytes is at least partially caused by its interference with immediate signal transduction events after activation. This mechanism might contribute to monocyte suppression in the tumor environment. - Highlights: • Lactic acid broadly delays LPS-induced gene expression in human monocytes. • Expression of important monocyte effector molecules is affected by lactic acid. • Interference of lactic acid with TLR signaling causes the delayed gene expression. • The profound effect of lactic acid might contribute to immune suppression in tumors.

Lactic acid delays the inflammatory response of human monocytes

International Nuclear Information System (INIS)

Peter, Katrin; Rehli, Michael; Singer, Katrin; Renner-Sattler, Kathrin; Kreutz, Marina

2015-01-01

Lactic acid (LA) accumulates under inflammatory conditions, e.g. in wounds or tumors, and influences local immune cell functions. We previously noted inhibitory effects of LA on glycolysis and TNF secretion of human LPS-stimulated monocytes. Here, we globally analyze the influence of LA on gene expression during monocyte activation. To separate LA-specific from lactate- or pH-effects, monocytes were treated for one or four hours with LPS in the presence of physiological concentrations of LA, sodium lactate (NaL) or acidic pH. Analyses of global gene expression profiles revealed striking effects of LA during the early stimulation phase. Up-regulation of most LPS-induced genes was significantly delayed in the presence of LA, while this inhibitory effect was attenuated in acidified samples and not detected after incubation with NaL. LA targets included genes encoding for important monocyte effector proteins like cytokines (e.g. TNF and IL-23) or chemokines (e.g. CCL2 and CCL7). LA effects were validated for several targets by quantitative RT-PCR and/or ELISA. Further analysis of LPS-signaling pathways revealed that LA delayed the phosphorylation of protein kinase B (AKT) as well as the degradation of IκBα. Consistently, the LPS-induced nuclear accumulation of NFκB was also diminished in response to LA. These results indicate that the broad effect of LA on gene expression and function of human monocytes is at least partially caused by its interference with immediate signal transduction events after activation. This mechanism might contribute to monocyte suppression in the tumor environment. - Highlights: • Lactic acid broadly delays LPS-induced gene expression in human monocytes. • Expression of important monocyte effector molecules is affected by lactic acid. • Interference of lactic acid with TLR signaling causes the delayed gene expression. • The profound effect of lactic acid might contribute to immune suppression in tumors

Diagnostic radiography as a risk factor for chronic myeloid and monocytic leukaemia (CML)

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Preston-Martin, S.; Thomas, D.C.; Yu, M.C.; Henderson, B.E.

1989-01-01

The study included 136 Los Angeles County residents aged 20-69 with chronic myeloid and monocytic leukemia CML diagnosed from 1979 to 1985 (cases) and 136 neighbourhood controls. During 3-20 years before diagnosis more cases than controls had radiographic examinations of back, gastrointestinal (GI) tract and kidneys, and cases more often had GI and back radiography on multiple occasions (odds ratio (OR) for back X-rays on five or more occasions = 12.0; P < 0.01). Published estimates were used to assign a minimum dose to active bone marrow for various radiographic procedures. ORs were estimated for cumulative marrow doses for each of four time periods (3-5 years, 6-10 years, 11-20 years and 3-20 years before diagnosis). ORs for exposure to 0.99, 100-999, 1000-1999 and ≥ 2000 mrad in the 3-20 years before diagnosis were 1.0, 1.4, 1.6 and 2.4 (P for highest exposure category and P for trend both < 0.05). The association was strongest for 6-10 years before diagnosis, and effects of radiation exposure during this period remained significant after consideration of other risk factors in a logistic regression analysis. (author)

All trans retinoic acid abrogates spontaneous monocytic growth in juvenile chronic myelomonocytic leukaemia.

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Cambier, N; Menot, M L; Schlageter, M H; Balitrand, N; Leblanc, T; Bordigoni, P; Rohrlich, P; Lamagnère, J P; Donadieu, J; Herbelin, C; Puissant, C; Gourand, F; Baruchel, A; Chomienne, C

2001-01-01

All trans retinoic acid, the active metabolite of vitamin A, exerts profound effects on cell differentiation. On normal myeloid progenitors, retinoids switch the differentiation program of granulo-macrophagic progenitors towards the granulocytic lineage and consequently reduce CFU-M colony formation. Bone marrow and peripheral blood mononuclear cells from children with Juvenile Chronic Myelomonocytic Leukaemia show typical spontaneous monocytic growth. We questioned whether in this disease, retinoids could switch myelomonocytic growth and inhibit the abnormal CFU-M colony proliferation. Ten JCML samples were studied in the presence of ATRA in methyl cellulose colony assay, before (CFU-C) or after (pre-CFU) liquid suspension culture. In vitro characteristics of JCML such as spontaneous monocytic growth in the absence of growth factor was noted in all patients. In the presence of leucocyte-conditioned medium, nine samples showed only CFU-M growth and one sample CFU-GM growth. Incubation with ATRA inhibited CFU-M colony formation in nine cases. Enhancement of granulocytic differentiation (CFU-G) was noted in nine cases. ATRA also inhibited CD34+ JCML monocytic growth and GM-CSF hypersensitivity. These data suggest that, in JCML progenitors, retinoid pathways are functional and inhibition of immature monocytic progenitors cells may be achieved with retinoids, without impeding granulocytic cell growth.

Innate immune activity conditions the effect of regulatory variants upon monocyte gene expression.

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Fairfax, Benjamin P; Humburg, Peter; Makino, Seiko; Naranbhai, Vivek; Wong, Daniel; Lau, Evelyn; Jostins, Luke; Plant, Katharine; Andrews, Robert; McGee, Chris; Knight, Julian C

2014-03-07

To systematically investigate the impact of immune stimulation upon regulatory variant activity, we exposed primary monocytes from 432 healthy Europeans to interferon-γ (IFN-γ) or differing durations of lipopolysaccharide and mapped expression quantitative trait loci (eQTLs). More than half of cis-eQTLs identified, involving hundreds of genes and associated pathways, are detected specifically in stimulated monocytes. Induced innate immune activity reveals multiple master regulatory trans-eQTLs including the major histocompatibility complex (MHC), coding variants altering enzyme and receptor function, an IFN-β cytokine network showing temporal specificity, and an interferon regulatory factor 2 (IRF2) transcription factor-modulated network. Induced eQTL are significantly enriched for genome-wide association study loci, identifying context-specific associations to putative causal genes including CARD9, ATM, and IRF8. Thus, applying pathophysiologically relevant immune stimuli assists resolution of functional genetic variants.

Osteopontin Prevents Monocyte Recirculation and Apoptosis

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Burdo, Tricia H.; Wood, Malcolm R.; Fox, Howard S.

2007-01-01

Cells of the monocyte/macrophage lineage have been shown to be the principal targets for productive HIV-1 replication within the central nervous system. In addition, HIV-1-associated dementia (HAD) has been shown to correlate with macrophage abundance in the brain. While increased entry of monocytes into the brain is thought to initiate this process, mechanisms that prevent macrophage egress from the brain and means that prevent macrophage death may also contribute to cell accumulation. We hy...

Human type II pneumocyte chemotactic responses to CXCR3 activation are mediated by splice variant A.

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Ji, Rong; Lee, Clement M; Gonzales, Linda W; Yang, Yi; Aksoy, Mark O; Wang, Ping; Brailoiu, Eugen; Dun, Nae; Hurford, Matthew T; Kelsen, Steven G

2008-06-01

Chemokine receptors control several fundamental cellular processes in both hematopoietic and structural cells, including directed cell movement, i.e., chemotaxis, cell differentiation, and proliferation. We have previously demonstrated that CXCR3, the chemokine receptor expressed by Th1/Tc1 inflammatory cells present in the lung, is also expressed by human airway epithelial cells. In airway epithelial cells, activation of CXCR3 induces airway epithelial cell movement and proliferation, processes that underlie lung repair. The present study examined the expression and function of CXCR3 in human alveolar type II pneumocytes, whose destruction causes emphysema. CXCR3 was present in human fetal and adult type II pneumocytes as assessed by immunocytochemistry, immunohistochemistry, and Western blotting. CXCR3-A and -B splice variant mRNA was present constitutively in cultured type II cells, but levels of CXCR3-B greatly exceeded CXCR3-A mRNA. In cultured type II cells, I-TAC, IP-10, and Mig induced chemotaxis. Overexpression of CXCR3-A in the A549 pneumocyte cell line produced robust chemotactic responses to I-TAC and IP-10. In contrast, I-TAC did not induce chemotactic responses in CXCR3-B and mock-transfected cells. Finally, I-TAC increased cytosolic Ca(2+) and activated the extracellular signal-regulated kinase, p38, and phosphatidylinositol 3-kinase (PI 3-kinase)/protein kinase B kinases only in CXCR3-A-transfected cells. These data indicate that the CXCR3 receptor is expressed by human type II pneumocytes, and the CXCR3-A splice variant mediates chemotactic responses possibly through Ca(2+) activation of both mitogen-activated protein kinase and PI 3-kinase signaling pathways. Expression of CXCR3 in alveolar epithelial cells may be important in pneumocyte repair from injury.

Gene expression results in lipopolysaccharide-stimulated monocytes depend significantly on the choice of reference genes

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Øvstebø Reidun

2010-05-01

Full Text Available Abstract Background Gene expression in lipopolysaccharide (LPS-stimulated monocytes is mainly studied by quantitative real-time reverse transcription PCR (RT-qPCR using GAPDH (glyceraldehyde 3-phosphate dehydrogenase or ACTB (beta-actin as reference gene for normalization. Expression of traditional reference genes has been shown to vary substantially under certain conditions leading to invalid results. To investigate whether traditional reference genes are stably expressed in LPS-stimulated monocytes or if RT-qPCR results are dependent on the choice of reference genes, we have assessed and evaluated gene expression stability of twelve candidate reference genes in this model system. Results Twelve candidate reference genes were quantified by RT-qPCR in LPS-stimulated, human monocytes and evaluated using the programs geNorm, Normfinder and BestKeeper. geNorm ranked PPIB (cyclophilin B, B2M (beta-2-microglobulin and PPIA (cyclophilin A as the best combination for gene expression normalization in LPS-stimulated monocytes. Normfinder suggested TBP (TATA-box binding protein and B2M as the best combination. Compared to these combinations, normalization using GAPDH alone resulted in significantly higher changes of TNF-α (tumor necrosis factor-alpha and IL10 (interleukin 10 expression. Moreover, a significant difference in TNF-α expression between monocytes stimulated with equimolar concentrations of LPS from N. meningitides and E. coli, respectively, was identified when using the suggested combinations of reference genes for normalization, but stayed unrecognized when employing a single reference gene, ACTB or GAPDH. Conclusions Gene expression levels in LPS-stimulated monocytes based on RT-qPCR results differ significantly when normalized to a single gene or a combination of stably expressed reference genes. Proper evaluation of reference gene stabiliy is therefore mandatory before reporting RT-qPCR results in LPS-stimulated monocytes.

Functional role of CD11c+ monocytes in atherogenesis associated with hypercholesterolemia

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Monocyte activation and migration into the arterial wall are key events in atherogenesis associated with hypercholesterolemia. CD11c/CD18, a beta2 integrin expressed on human monocytes and a subset of mouse monocytes, has been shown to play a distinct role in human monocyte adhesion on endothelial c...

Alterations in calcium metabolism during human monocyte activation

International Nuclear Information System (INIS)

Scully, S.P.

1984-01-01

Human peripheral blood monocytes have been prepared from plateletpheresis residues by counterflow centrifugal elutriation in sufficient quantities to enable quantitative studies of cell calcium. Kinetic analysis of 45 Ca exchange data in resting monocytes was compatible with a model of cellular calcium containing three exchangeable calcium pools. These pools are thought to represent a putative ectocellular pool, a putative cytoplasmic chelated pool, and a putative organelle sequestered pool. Exposure of monocytes to the plant lectin Con A at a concentration that maximally simulated superoxide production caused an increase in the size and a doubling in the exchange rate of the putative cytoplasmic pool without a change in the other cellular pools. The cytoplasmic ionized calcium, [Ca]/sub i/, measured with the fluorescent probe, Quin 2 rose from a resting level of 83 nM to 165 mN within 30 sec of exposure to Con A. This increase in cytoplasmic calcium preceded the release of superoxide radicals. Calcium transport and calcium ATPase activities were identified and characterized in plasma membrane vesicles prepared from monocytes. Both activities were strictly dependent on ATP and Mg, had a Km/sub Ca/ in the submicromolar range and were stimulated by calmodulin. Thus, it seems that monocyte calcium is in a dynamic steady state that is a balance between efflux and influx rates, and that the activation of these cells results in the transition to a new steady state. The alteration in [Ca]/sub i/ that accompany the new steady state are essential for superoxide production by human monocytes

HCMV Reprogramming of Infected Monocyte Survival and Differentiation: A Goldilocks Phenomenon

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Emily V. Stevenson

2014-02-01

Full Text Available The wide range of disease pathologies seen in multiple organ sites associated with human cytomegalovirus (HCMV infection results from the systemic hematogenous dissemination of the virus, which is mediated predominately by infected monocytes. In addition to their role in viral spread, infected monocytes are also known to play a key role in viral latency and life-long persistence. However, in order to utilize infected monocytes for viral spread and persistence, HCMV must overcome a number of monocyte biological hurdles, including their naturally short lifespan and their inability to support viral gene expression and replication. Our laboratory has shown that HCMV is able to manipulate the biology of infected monocytes in order to overcome these biological hurdles by inducing the survival and differentiation of infected monocytes into long-lived macrophages capable of supporting viral gene expression and replication. In this current review, we describe the unique aspects of how HCMV promotes monocyte survival and differentiation by inducing a “finely-tuned” macrophage cell type following infection. Specifically, we describe the induction of a uniquely polarized macrophage subset from infected monocytes, which we argue is the ideal cellular environment for the initiation of viral gene expression and replication and, ultimately, viral spread and persistence within the infected host.

CD14+ monocytes promote the immunosuppressive effect of human umbilical cord matrix stem cells

International Nuclear Information System (INIS)

Wang, Ding; Chen, Ke; Du, Wei Ting; Han, Zhi-Bo; Ren, He; Chi, Ying

2010-01-01

Here, the effect of CD14 + monocytes on human umbilical cord matrix stem cell (hUC-MSC)-mediated immunosuppression was studied in vitro. hUC-MSCs exerted a potent inhibitory effect on the proliferation and interferon-γ (IFN-γ) secretion capacities of CD4 + and CD8 + T cells in response to anti-CD3/CD28 stimulation. Transwell co-culture system revealed that the suppressive effect was primarily mediated by soluble factors. Addition of prostaglandin synthesis inhibitors (indomethacin or NS-398) almost completely abrogated the immunosuppression activity of hUC-MSCs, identifying prostaglandin E 2 (PGE 2 ) as an important soluble mediator. CD14 + monocytes were found to be able to enhance significantly the immunosuppressive effect of hUC-MSCs in a dose-dependent fashion. Moreover, the inflammatory cytokine IL-1β, either exogenously added or produced by CD14 + monocytes in culture, could trigger expression of high levels of PGE 2 by hUC-MSCs, whereas inclusion of the IL-1 receptor antagonist (IL-1RA) in the culture down-regulated not only PGE 2 expression, but also reversed the promotional effect of CD14 + monocytes and partially restored CD4 + and CD8 + T cell proliferation and IFN-γ secretion. Our data demonstrate an important role of monocytes in the hUC-MSC-induced immunomodulation, which may have important implications in future efforts to explore the clinical potentials of hUC-MSCs.

Maturation and demise of human primary monocytes by carbon nanotubes

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De Nicola, Milena; Mirabile Gattia, Daniele; Traversa, Enrico; Ghibelli, Lina

2013-06-01

The possibility of exploiting carbon nanotubes (CNT) in biomedical practices requires thorough analysis of the chemical or bulk effects they may exert on the immune system, the complex network that recognizes and eliminates foreign particles. In particular, the phagocytosing ability of cells belonging to the monocyte/macrophage lineage may render these immune cells an ideal toxicological target of pristine CNT, which may form aggregates of size exceeding monocyte/macrophage phagocytosing plasticity. To shed light on this issue, we analyzed the effects that pristine multi-walled CNT (MWCNT) without metal or biological impurities exert on survival and activation of freshly explanted human peripheral blood monocytes, analyzing in parallel the non-phagocytosing lymphocytes, and using graphite as control carbon material. MWCNT (diameter 10-50 nm, length up to 10 μm) exert two different toxic effects on mononuclear leukocytes: a minor apoptogenic effect (on lymphocytes > monocytes), and a major, apoptosis-independent effect that exclusively and deeply affect monocyte homeostasis. Analysis of monocyte number, adhesion, redox equilibrium, and the differentiation markers CD14 and CD11b reveals that MWCNT cause the selective disappearance of phagocytosis-competent monocytes by mechanisms related to the presence of large nanoparticle aggregates, suggesting phenomena of bulk toxicity possibly consisting of frustrated phagocytosis. At the same time, MWCNT stimulate adhesion of the phagocytosis-incompetent monocytes, and their differentiation toward a peculiar maturation asset. These observations point out novel mechanisms of CNT toxicity, renewing concerns that they may impair the innate immune system deranging the inflammatory responses.

Maturation and demise of human primary monocytes by carbon nanotubes

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De Nicola, Milena, E-mail: milena.de.nicola@uniroma2.it [University of Rome ' Tor Vergata' , Department of Biology (Italy); Mirabile Gattia, Daniele, E-mail: daniele.mirabile@enea.it [UTTMAT, ENEA-C.R. Casaccia (Italy); Traversa, Enrico, E-mail: Enrico.Traversa@kaust.edu.sa [King Abdullah University of Science and Technology (KAUST), Division of Physical Science and Engineering (Saudi Arabia); Ghibelli, Lina, E-mail: ghibelli@uniroma2.it [University of Rome ' Tor Vergata' , Department of Biology (Italy)

2013-06-15

The possibility of exploiting carbon nanotubes (CNT) in biomedical practices requires thorough analysis of the chemical or bulk effects they may exert on the immune system, the complex network that recognizes and eliminates foreign particles. In particular, the phagocytosing ability of cells belonging to the monocyte/macrophage lineage may render these immune cells an ideal toxicological target of pristine CNT, which may form aggregates of size exceeding monocyte/macrophage phagocytosing plasticity. To shed light on this issue, we analyzed the effects that pristine multi-walled CNT (MWCNT) without metal or biological impurities exert on survival and activation of freshly explanted human peripheral blood monocytes, analyzing in parallel the non-phagocytosing lymphocytes, and using graphite as control carbon material. MWCNT (diameter 10-50 nm, length up to 10 {mu}m) exert two different toxic effects on mononuclear leukocytes: a minor apoptogenic effect (on lymphocytes > monocytes), and a major, apoptosis-independent effect that exclusively and deeply affect monocyte homeostasis. Analysis of monocyte number, adhesion, redox equilibrium, and the differentiation markers CD14 and CD11b reveals that MWCNT cause the selective disappearance of phagocytosis-competent monocytes by mechanisms related to the presence of large nanoparticle aggregates, suggesting phenomena of bulk toxicity possibly consisting of frustrated phagocytosis. At the same time, MWCNT stimulate adhesion of the phagocytosis-incompetent monocytes, and their differentiation toward a peculiar maturation asset. These observations point out novel mechanisms of CNT toxicity, renewing concerns that they may impair the innate immune system deranging the inflammatory responses.

Maturation and demise of human primary monocytes by carbon nanotubes

International Nuclear Information System (INIS)

De Nicola, Milena; Mirabile Gattia, Daniele; Traversa, Enrico; Ghibelli, Lina

2013-01-01

The possibility of exploiting carbon nanotubes (CNT) in biomedical practices requires thorough analysis of the chemical or bulk effects they may exert on the immune system, the complex network that recognizes and eliminates foreign particles. In particular, the phagocytosing ability of cells belonging to the monocyte/macrophage lineage may render these immune cells an ideal toxicological target of pristine CNT, which may form aggregates of size exceeding monocyte/macrophage phagocytosing plasticity. To shed light on this issue, we analyzed the effects that pristine multi-walled CNT (MWCNT) without metal or biological impurities exert on survival and activation of freshly explanted human peripheral blood monocytes, analyzing in parallel the non-phagocytosing lymphocytes, and using graphite as control carbon material. MWCNT (diameter 10–50 nm, length up to 10 μm) exert two different toxic effects on mononuclear leukocytes: a minor apoptogenic effect (on lymphocytes > monocytes), and a major, apoptosis-independent effect that exclusively and deeply affect monocyte homeostasis. Analysis of monocyte number, adhesion, redox equilibrium, and the differentiation markers CD14 and CD11b reveals that MWCNT cause the selective disappearance of phagocytosis-competent monocytes by mechanisms related to the presence of large nanoparticle aggregates, suggesting phenomena of bulk toxicity possibly consisting of frustrated phagocytosis. At the same time, MWCNT stimulate adhesion of the phagocytosis-incompetent monocytes, and their differentiation toward a peculiar maturation asset. These observations point out novel mechanisms of CNT toxicity, renewing concerns that they may impair the innate immune system deranging the inflammatory responses.

Maturation and demise of human primary monocytes by carbon nanotubes

KAUST Repository

De Nicola, Milena D.

2013-05-17

The possibility of exploiting carbon nanotubes (CNT) in biomedical practices requires thorough analysis of the chemical or bulk effects they may exert on the immune system, the complex network that recognizes and eliminates foreign particles. In particular, the phagocytosing ability of cells belonging to the monocyte/macrophage lineage may render these immune cells an ideal toxicological target of pristine CNT, which may form aggregates of size exceeding monocyte/macrophage phagocytosing plasticity. To shed light on this issue, we analyzed the effects that pristine multi-walled CNT (MWCNT) without metal or biological impurities exert on survival and activation of freshly explanted human peripheral blood monocytes, analyzing in parallel the non-phagocytosing lymphocytes, and using graphite as control carbon material. MWCNT (diameter 10-50 nm, length up to 10 μm) exert two different toxic effects on mononuclear leukocytes: a minor apoptogenic effect (on lymphocytes > monocytes), and a major, apoptosis-independent effect that exclusively and deeply affect monocyte homeostasis. Analysis of monocyte number, adhesion, redox equilibrium, and the differentiation markers CD14 and CD11b reveals that MWCNT cause the selective disappearance of phagocytosis-competent monocytes by mechanisms related to the presence of large nanoparticle aggregates, suggesting phenomena of bulk toxicity possibly consisting of frustrated phagocytosis. At the same time, MWCNT stimulate adhesion of the phagocytosis-incompetent monocytes, and their differentiation toward a peculiar maturation asset. These observations point out novel mechanisms of CNT toxicity, renewing concerns that they may impair the innate immune system deranging the inflammatory responses. © 2013 Springer Science+Business Media Dordrecht.

The continuum of monocyte phenotypes: Experimental evidence and prognostic utility in assessing cardiovascular risk.

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Cignarella, Andrea; Tedesco, Serena; Cappellari, Roberta; Fadini, Gian Paolo

2018-03-30

The monocyte-macrophage cell lineage represents a major player in innate immunity, and is involved in many physiologic and pathologic conditions. Particularly, monocyte-macrophages play a very important role in atherosclerosis and cardiovascular disease. Monocyte heterogeneity is well recognized but the biologic and clinical meaning of the various monocyte subtypes is not entirely understood. Traditionally, monocytes can be divided in classical, intermediate, and nonclassical based on expression of the surface antigens CD14 and CD16. While macrophage diversity is now well recognized to organize as a continuum, monocyte subsets have long been considered as separated entities. However, mounting evidence obtained by tracking the ontology of human monocytes help clarifying that monocytes mature from classical to nonclassical ones, through an intermediate phenotype. This concept is therefore best depicted as a continuum, whereas the subdivision into discrete CD14/CD16 subsets appears an oversimplification. In this review, we discuss the evidence supporting the existence of a monocyte continuum along with the technical challenges of monocyte characterization. In particular, we describe the advantage of considering monocytes along a continuous distribution for the evaluation of cardiovascular risk. We make the point that small transition along the monocyte continuum better reflects cardiovascular risk than a simplified analysis of discrete monocyte subsets. Recognizing the monocyte continuum can be helpful to model other pathophysiologic conditions where these cells are involved. ©2018 Society for Leukocyte Biology.

CD14-dependent monocyte isolation enhances phagocytosis of listeria monocytogenes by proinflammatory, GM-CSF-derived macrophages.

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Caroline Neu

Full Text Available Macrophages are an important line of defence against invading pathogens. Human macrophages derived by different methods were tested for their suitability as models to investigate Listeria monocytogenes (Lm infection and compared to macrophage-like THP-1 cells. Human primary monocytes were isolated by either positive or negative immunomagnetic selection and differentiated in the presence of granulocyte macrophage colony-stimulating factor (GM-CSF or macrophage colony-stimulating factor (M-CSF into pro- or anti-inflammatory macrophages, respectively. Regardless of the isolation method, GM-CSF-derived macrophages (GM-Mφ stained positive for CD206 and M-CSF-derived macrophages (M-Mφ for CD163. THP-1 cells did not express CD206 or CD163 following incubation with PMA, M- or GM-CSF alone or in combination. Upon infection with Lm, all primary macrophages showed good survival at high multiplicities of infection whereas viability of THP-1 was severely reduced even at lower bacterial numbers. M-Mφ generally showed high phagocytosis of Lm. Strikingly, phagocytosis of Lm by GM-Mφ was markedly influenced by the method used for isolation of monocytes. GM-Mφ derived from negatively isolated monocytes showed low phagocytosis of Lm whereas GM-Mφ generated from positively selected monocytes displayed high phagocytosis of Lm. Moreover, incubation with CD14 antibody was sufficient to enhance phagocytosis of Lm by GM-Mφ generated from negatively isolated monocytes. By contrast, non-specific phagocytosis of latex beads by GM-Mφ was not influenced by treatment with CD14 antibody. Furthermore, phagocytosis of Lactococcus lactis, Escherichia coli, human cytomegalovirus and the protozoan parasite Leishmania major by GM-Mφ was not enhanced upon treatment with CD14 antibody indicating that this effect is specific for Lm. Based on these observations, we propose macrophages derived by ex vivo differentiation of negatively selected human primary monocytes as the most

Platelets as a Novel Source of Pro-Inflammatory Chemokine CXCL14

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Alexander Witte

2017-03-01

Full Text Available Objective: Platelets are a major source of chemokines. Here, we demonstrate for the first time that platelets express significant amounts of CXCL14 and disclose powerful effects of platelet-derived CXCL14 on monocyte and endothelial migration. Methods: The expression of CXCL14 in platelets and in the supernatant of activated platelets was analysed by immunoblotting, ELISA, and flow cytometry. The effect of platelet-derived CXCL14 on monocyte migration was evaluated using a modified Boyden chamber. The effect of CXCL14 on monocyte phagocytosis was tested by using fluorochrome-labelled E.coli particles. The effect of platelet-derived CXCL14 on endothelial migration was explored by the use of an endothelial scratch assay. Results: Hitherto unrecognized expression of CXCL14 in human and murine platelets was uncovered by immunoblotting. Activation with platelet agonists such as adenosine-di-phosphate (ADP, collagen-related peptide (CRP, or thrombin-receptor activating peptide (TRAP, increased CXCL14 surface expression (flow cytometry and release into the supernatant (immunoblotting, ELISA. Since CXCL14 is known to be chemotactic for CD14+ monocytes, we investigated the chemotactic potential of platelet-derived CXCL14 on human monocytes. Activated platelet supernatant induced monocyte migration, which was counteracted upon neutralization of platelet-derived CXCL14 as compared to IgG control. Blocking of the chemokine receptor CXCR4, but not CXCR7, reduced the number of migratory monocytes towards recombinant CXCL14, suggesting the involvement of CXCR4 in the CXCL14-directed monocyte chemotaxis. Recombinant CXCL14 enhanced the phagocytic uptake of E.coli particles by monocytes. In scratch assays with cultured endothelial cells (HUVECs, platelet-derived CXCL14 counteracted the pro-angiogenic effects of VEGF, supporting its previously recognized angiostatic potential. Conclusions: Platelets are a relevant source of CXCL14. Platelet-derived CXCL14 at the

PECAM-1 polymorphism affects monocyte adhesion to endothelial cells.

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Goodman, Reyna S; Kirton, Christopher M; Oostingh, Gertie J; Schön, Michael P; Clark, Michael R; Bradley, J Andrew; Taylor, Craig J

2008-02-15

Platelet endothelial cell adhesion molecule-1 (PECAM-1/CD31) plays an important role in leukocyte-endothelial cell adhesion and transmigration. Single nucleotide polymorphisms of PECAM-1 encoding amino acid substitutions at positions 98 leucine/valine (L/V), 536 serine/asparagine (S/N), and 643 arginine/glycine (R/G) occur in strong genetic linkage resulting in two common haplotypes (LSR and VNG). These PECAM-1 polymorphisms are associated with graft-versus-host disease after hematopoietic stem cell transplantation and with cardiovascular disease, but whether they influence PECAM-1 function is unknown. We examined the effect of homozygous and heterozygous expression of the PECAM-1 LSR and VNG genotypes on the adhesive interactions of peripheral blood monocytes and activated endothelial cell monolayers under shear stress in a flow-based cell adhesion assay. There was no difference in monocyte adhesion between the two homozygous genotypes of PECAM-1 but when monocytes expressed both alleles in heterozygous form, firm adhesion of monocytes to endothelial cells was markedly increased. PECAM-1 polymorphism expressed in homozygous or heterozygous form by endothelial cells did not influence monocyte adhesion. This is, to our knowledge, the first demonstration that PECAM-1 genotype can alter the level of monocyte binding to endothelial cells and a demonstration that heterozygous expression of a polymorphic protein may lead to altered function.

Monocytes of patients with familial hypercholesterolemia show alterations in cholesterol metabolism

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Soufi Muhidien

2008-11-01

Full Text Available Abstract Background Elevated plasma cholesterol promotes the formation of atherosclerotic lesions in which monocyte-derived lipid-laden macrophages are frequently found. To analyze, if circulating monocytes already show increased lipid content and differences in lipoprotein metabolism, we compared monocytes from patients with Familial Hypercholesterolemia (FH with those from healthy individuals. Methods Cholesterol and oxidized cholesterol metabolite serum levels of FH and of healthy, gender/age matched control subjects were measured by combined gas chromatography – mass spectroscopy. Monocytes from patients with FH and from healthy subjects were isolated by antibody-assisted density centrifugation. Gene expression profiles of isolated monocytes were measured using Affymetrix HG-U 133 Plus 2.0 microarrays. We compared monocyte gene expression profiles from FH patients with healthy controls using a Welch T-test with correction for multiple testing (p Results Using microarray analysis we found in FH patients a significant up-regulation of 1,617 genes and a down-regulation of 701 genes compared to monocytes from healthy individuals. These include genes of proteins that are involved in the uptake, biosynthesis, disposition, and cellular efflux of cholesterol. In addition, plasma from FH patients contains elevated amounts of sterols and oxysterols. An increased uptake of oxidized as well as of native LDL by FH monocytes combined with a down-regulation of NPC1 and ABCA1 explains the lipid accumulation observed in these cells. Conclusion Our data demonstrate that circulating FH monocytes show differences in cell physiology that may contribute to the early onset of atherosclerosis in this disease.

Effect of Serum and Oxygen Concentration on Gene Expression and Secretion of Paracrine Factors by Mesenchymal Stem Cells

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Patrick Page

2014-01-01

Full Text Available Mesenchymal stem cells (MSC secrete paracrine factors that may exert a protective effect on the heart after coronary artery occlusion. This study was done to determine the effect of hypoxia and serum levels on the mRNA expression and secretion of paracrine factors. Mouse bone marrow MSC were cultured with 5% or 20% serum and in either normoxic (21% O2 or hypoxic (1% O2 conditions. Expression of mRNA for vascular endothelial growth factor (VEGF, monocyte chemotactic protein-1 (MCP-1, macrophage inflammatory protein-1α (MIP-1α, MIP-1β, and matrix metalloproteinase-2 (MMP-2 was determined by RT-qPCR. Secretion into the culture media was determined by ELISA. Hypoxia caused a reduction in gene expression for MCP-1 and an increase for VEGF (5% serum, MIP-1α, MIP-1β, and MMP-2. Serum reduction lowered gene expression for VEGF (normoxia, MCP-1 (hypoxia, MIP-1α (hypoxia, MIP-1β (hypoxia, and MMP-2 (hypoxia and increased gene expression for MMP-2 (normoxia. The level of secretion of these factors into the media generally paralleled gene expression with some exceptions. These data demonstrate that serum and oxygen levels have a significant effect on the gene expression and secretion of paracrine factors by MSC which will affect how MSC interact in vivo during myocardial ischemia.

Death of Monocytes through Oxidative Burst of Macrophages and Neutrophils: Killing in Trans.

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Viviane Ponath

Full Text Available Monocytes and their descendants, macrophages, play a key role in the defence against pathogens. They also contribute to the pathogenesis of inflammatory diseases. Therefore, a mechanism maintaining a balance in the monocyte/macrophage population must be postulated. Our previous studies have shown that monocytes are impaired in DNA repair, rendering them vulnerable to genotoxic stress while monocyte-derived macrophages are DNA repair competent and genotoxic stress-resistant. Based on these findings, we hypothesized that monocytes can be selectively killed by reactive oxygen species (ROS produced by activated macrophages. We also wished to know whether monocytes and macrophages are protected against their own ROS produced following activation. To this end, we studied the effect of the ROS burst on DNA integrity, cell death and differentiation potential of monocytes. We show that monocytes, but not macrophages, stimulated for ROS production by phorbol-12-myristate-13-acetate (PMA undergo apoptosis, despite similar levels of initial DNA damage. Following co-cultivation with ROS producing macrophages, monocytes displayed oxidative DNA damage, accumulating DNA single-strand breaks and a high incidence of apoptosis, reducing their ability to give rise to new macrophages. Killing of monocytes by activated macrophages, termed killing in trans, was abolished by ROS scavenging and was also observed in monocytes co-cultivated with ROS producing activated granulocytes. The data revealed that monocytes, which are impaired in the repair of oxidised DNA lesions, are vulnerable to their own ROS and ROS produced by macrophages and granulocytes and support the hypothesis that this is a mechanism regulating the amount of monocytes and macrophages in a ROS-enriched inflammatory environment.

Monocyte galactose/N-acetylgalactosamine-specific C-type lectin receptor stimulant immunotherapy of an experimental glioma. Part 1: stimulatory effects on blood monocytes and monocyte-derived cells of the brain

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Kushchayev SV

2012-09-01

Full Text Available Sergiy V Kushchayev,1 Tejas Sankar,1 Laura L Eggink,4,5 Yevgeniya S Kushchayeva,5 Philip C Wiener,1,5 J Kenneth Hoober,5,6 Jennifer Eschbacher,3 Ruolan Liu,2 Fu-Dong Shi,2 Mohammed G Abdelwahab,4 Adrienne C Scheck,4 Mark C Preul11Neurosurgery Research Laboratory, 2Neuroimmunology Laboratory, 3Department of Pathology, 4Neurooncology Research, Barrow Neurological Institute, St Joseph's Hospital and Medical Center, Phoenix, 5School of Life Sciences, Arizona State University, Tempe, 6Susavion Biosciences, Inc, Tempe, AZ, USAObjectives: Immunotherapy with immunostimulants is an attractive therapy against gliomas. C-type lectin receptors specific for galactose/N-acetylgalactosamine (GCLR regulate cellular differentiation, recognition, and trafficking of monocyte-derived cells. A peptide mimetic of GCLR ligands (GCLRP was used to activate blood monocytes and populations of myeloid-derived cells against a murine glioblastoma.Methods: The ability of GCLRP to stimulate phagocytosis by human microglia and monocyte-derived cells of the brain (MDCB isolated from a human glioblastoma was initially assessed in vitro. Induction of activation markers on blood monocytes was assayed by flow cytometry after administration of GCLRP to naive mice. C57BL/6 mice underwent stereotactic intracranial implantation of GL261 glioma cells and were randomized for tumor size by magnetic resonance imaging, which was also used to assess increase in tumor size. Brain tumor tissues were analyzed using flow cytometry, histology, and enzyme-linked immunosorbent assay with respect to tumor, peritumoral area, and contralateral hemisphere regions.Results: GCLRP exhibited strong stimulatory effect on MDCBs and blood monocytes in vitro and in vivo. GCLRP was associated with an increased percentage of precursors of dendritic cells in the blood (P = 0.003, which differentiated into patrolling macrophages in tumoral (P = 0.001 and peritumoral areas (P = 0.04, rather than into dendritic cells

Properties of human blood monocytes. I. CD91 expression and log orthogonal light scatter provide a robust method to identify monocytes that is more accurate than CD14 expression.

Science.gov (United States)

Hudig, Dorothy; Hunter, Kenneth W; Diamond, W John; Redelman, Doug

2014-03-01

This study was designed to improve identification of human blood monocytes by using antibodies to molecules that occur consistently on all stages of monocyte development and differentiation. We examined blood samples from 200 healthy adults without clinically diagnosed immunological abnormalities by flow cytometry (FCM) with multiple combinations of antibodies and with a hematology analyzer (Beckman LH750). CD91 (α2 -macroglobulin receptor) was expressed only by monocytes and to a consistent level among subjects [mean median fluorescence intensity (MFI) = 16.2 ± 3.2]. Notably, only 85.7 ± 5.82% of the CD91(+) monocytes expressed high levels of the classical monocyte marker CD14, with some CD91(+) CD16(+) cells having negligible CD14, indicating that substantial FCM under-counts will occur when monocytes are identified by high CD14. CD33 (receptor for sialyl conjugates) was co-expressed with CD91 on monocytes but CD33 expression varied by nearly ten-fold among subjects (mean MFI = 17.4 ± 7.7). In comparison to FCM analyses, the hematology analyzer systematically over-counted monocytes and eosinophils while lymphocyte and neutrophil differential values generally agreed with FCM methods. CD91 is a better marker to identify monocytes than CD14 or CD33. Furthermore, FCM (with anti-CD91) identifies monocytes better than a currently used clinical CBC instrument. Use of anti-CD91 together with anti-CD14 and anti-CD16 supports the identification of the diagnostically significant monocyte populations with variable expression of CD14 and CD16. Copyright © 2013 Clinical Cytometry Society.

Increase in Peripheral Blood Intermediate Monocytes is Associated with the Development of Recent-Onset Type 1 Diabetes Mellitus in Children.

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Ren, Xiaoya; Mou, Wenjun; Su, Chang; Chen, Xi; Zhang, Hui; Cao, Bingyan; Li, Xiaoqiao; Wu, Di; Ni, Xin; Gui, Jingang; Gong, Chunxiu

2017-01-01

Monocytes play important roles in antigen presentation and cytokine production to achieve a proper immune response, and are therefore largely implicated in the development and progression of autoimmune diseases. The aim of this study was to analyze the change in the intermediate (CD14+CD16+) monocyte subset in children with recent-onset type 1 diabetes mellitus (T1DM) and its possible association with clinical parameters reflecting islet β-cell dysfunction. Compared with age- and sex-matched healthy controls, intermediate monocytes were expanded in children with T1DM, which was positively associated with hemoglobin A1C and negatively associated with serum insulin and C-peptide. Interestingly, the intermediate monocytes in T1DM patients expressed higher levels of human leukocyte antigen-DR and CD86, suggesting better antigen presentation capability. Further analysis revealed that the frequency of CD45RO+CD4+ memory T cells was increased in the T1DM patients, and the memory T cell content was well correlated with the increase in intermediate monocytes. These results suggest that expanded intermediate monocytes are a predictive factor for the poor residual islet β-cell function in children with recent-onset T1DM.

Methylglyoxal-bis-guanylhydrazone inhibits osteopontin expression and differentiation in cultured human monocytes.

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Jin, Xia; Xu, Hua; McGrath, Michael S

2018-01-01

Monocyte activation and polarization play essential roles in many chronic inflammatory diseases. An imbalance of M1 and M2 macrophage activation (pro-inflammatory and alternatively activated, respectively) is believed to be a key aspect in the etiology of these diseases, thus a therapeutic approach that regulates macrophage activation could be of broad clinical relevance. Methylglyoxal-bis-guanylhydrazone (MGBG), a regulator of polyamine metabolism, has recently been shown to be concentrated in monocytes and macrophages, and interfere with HIV integration into the DNA of these cells in vitro. RNA expression analysis of monocytes from HIV+ and control donors with or without MGBG treatment revealed the only gene to be consistently down regulated by MGBG to be osteopontin (OPN). The elevated expression of this pro-inflammatory cytokine and monocyte chemoattractant is associated with various chronic inflammatory diseases. We demonstrate that MGBG is a potent inhibitor of secreted OPN (sOPN) in cultured monocytes with 50% inhibition achieved at 0.1 μM of the drug. Furthermore, inhibition of OPN RNA transcription in monocyte cultures occurs at similar concentrations of the drug. During differentiation of monocytes into macrophages in vitro, monocytes express cell surface CD16 and the cells undergo limited DNA synthesis as measured by uptake of BrdU. MGBG inhibited both activities at similar doses to those regulating OPN expression. In addition, monocyte treatment with MGBG inhibited differentiation into both M1 and M2 classes of macrophages at non-toxic doses. The inhibition of differentiation and anti-OPN effects of MGBG were specific for monocytes in that differentiated macrophages were nearly resistant to MGBG activities. Thus MGBG may have potential therapeutic utility in reducing or normalizing OPN levels and regulating monocyte activation in diseases that involve chronic inflammation.

Interleukin 17 receptor A modulates monocyte subsets and macrophage generation in vivo.

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Shuwang Ge

Full Text Available Interleukin (IL-17A signaling via Interleukin 17 receptor A (Il17ra contributes to the inflammatory host response by inducing recruitment of innate immune cells, but also plays a role in homeostatic neutrophilic granulocyte regulation. Monocytes, the other main innate immune cell, have a longer life span and can pursue multiple differentiation pathways towards tissue macrophages. Monocytes are divided into two subpopulations by expression of the Ly6C/Gr1 surface marker in mice. We here investigated the role of Il17ra in monocyte homeostasis and macrophage generation. In Il17ra(-/- and in mixed bone marrow chimeric wt/Il17ra(-/- mice, the concentrations of circulating Il17ra(-/- Gr1(low monocytes were significantly decreased compared to wt cells. Pulmonary, splenic and resident peritoneal Il17ra(-/- macrophages were significantly fewer than of wt origin. Bone marrow progenitor and monocyte numbers were equal, but the proportion of Il17ra(-/- Gr1(low monocytes was already decreased at bone marrow level. After monocyte depletion, initial Gr1(high and Gr1(low monocyte regeneration of Il17ra(-/- and wt cells was very similar. However, Il17ra(-/- Gr1(low counts were not sustained. After labeling with either fluorescent beads or BrdU, Il17ra(-/- Gr1(high monocyte transition to Gr1(low cells was not detectable unlike wt cells. Monocyte recruitment in acute peritonitis, which is known to be largely due to Gr1(high cell migration, was unaffected in an identical environment. Unilateral ureteral obstruction induces a less acute inflammatory and fibrotic kidney injury. Compared to wt cells in the same environment, Il17ra(-/- macrophage accumulation in the kidney was decreased. In the absence of Il17ra on all myeloid cells, renal fibrosis was significantly attenuated. Our data show that Il17ra modulates Gr1(low monocyte counts and suggest defective Gr1(high to Gr1(low monocyte transition as an underlying mechanism. Lack of Il17ra altered homeostatic tissue

The acute monocytic leukemias: multidisciplinary studies in 45 patients.

Science.gov (United States)

Straus, D J; Mertelsmann, R; Koziner, B; McKenzie, S; de Harven, E; Arlin, Z A; Kempin, S; Broxmeyer, H; Moore, M A; Menendez-Botet, C J; Gee, T S; Clarkson, B D

1980-11-01

The clinical and laboratory features of 37 patients with variants of acute monocytic leukemia are described. Three of these 37 patients who had extensive extramedullary leukemic tissue infiltration are examples of true histiocytic "lymphomas." Three additional patients with undifferentiated leukemias, one patient with refractory anemia with excess of blasts, one patient with chronic myelomonocytic leukemia, one patient with B-lymphocyte diffuse "histiocytic" lymphoma and one patient with "null" cell, terminal deoxynucleotidyl transferase-positive lymphoblastic lymphoma had bone marrow cells with monocytic features. Another patient had dual populations of lymphoid and monocytoid leukemic cells. The true monocytic leukemias, acute monocytic leukemia (AMOL) and acute myelomonocytic leukemia (AMMOL), are closely related to acute myelocytic leukemia (AML) morphologically and by their response to chemotherapy. like AML, the leukemic cells from the AMMOL and AMOL patients form leukemic clusters in semisolid media. Cytochemical staining of leukemic cells for nonspecific esterases, presence of Fc receptor on the cell surface, phagocytic ability, low TdT activity, presence of surface "ruffles" and "ridges" on scanning EM, elevations of serum lysozyme, and clinical manifestations of leukemic tissue infiltration are features which accompanied monocytic differentiation in these cases.

Deciphering the transcriptional circuitry of microRNA genes expressed during human monocytic differentiation

KAUST Repository

Schmeier, Sebastian; MacPherson, Cameron R; Essack, Magbubah; Kaur, Mandeep; Schaefer, Ulf; Suzuki, Harukazu; Hayashizaki, Yoshihide; Bajic, Vladimir B.

2009-01-01

Background: Macrophages are immune cells involved in various biological processes including host defence, homeostasis, differentiation, and organogenesis. Disruption of macrophage biology has been linked to increased pathogen infection, inflammation and malignant diseases. Differential gene expression observed in monocytic differentiation is primarily regulated by interacting transcription factors (TFs). Current research suggests that microRNAs (miRNAs) degrade and repress translation of mRNA, but also may target genes involved in differentiation. We focus on getting insights into the transcriptional circuitry regulating miRNA genes expressed during monocytic differentiation. Results: We computationally analysed the transcriptional circuitry of miRNA genes during monocytic differentiation using in vitro time-course expression data for TFs and miRNAs. A set of TF?miRNA associations was derived from predicted TF binding sites in promoter regions of miRNA genes. Time-lagged expression correlation analysis was utilised to evaluate the TF?miRNA associations. Our analysis identified 12 TFs that potentially play a central role in regulating miRNAs throughout the differentiation process. Six of these 12 TFs (ATF2, E2F3, HOXA4, NFE2L1, SP3, and YY1) have not previously been described to be important for monocytic differentiation. The remaining six TFs are CEBPB, CREB1, ELK1, NFE2L2, RUNX1, and USF2. For several miRNAs (miR-21, miR-155, miR-424, and miR-17-92), we show how their inferred transcriptional regulation impacts monocytic differentiation. Conclusions: The study demonstrates that miRNAs and their transcriptional regulatory control are integral molecular mechanisms during differentiation. Furthermore, it is the first study to decipher on a large-scale, how miRNAs are controlled by TFs during human monocytic differentiation. Subsequently, we have identified 12 candidate key controllers of miRNAs during this differentiation process. 2009 Schmeier et al; licensee Bio

Deciphering the transcriptional circuitry of microRNA genes expressed during human monocytic differentiation

KAUST Repository

Schmeier, Sebastian

2009-12-10

Background: Macrophages are immune cells involved in various biological processes including host defence, homeostasis, differentiation, and organogenesis. Disruption of macrophage biology has been linked to increased pathogen infection, inflammation and malignant diseases. Differential gene expression observed in monocytic differentiation is primarily regulated by interacting transcription factors (TFs). Current research suggests that microRNAs (miRNAs) degrade and repress translation of mRNA, but also may target genes involved in differentiation. We focus on getting insights into the transcriptional circuitry regulating miRNA genes expressed during monocytic differentiation. Results: We computationally analysed the transcriptional circuitry of miRNA genes during monocytic differentiation using in vitro time-course expression data for TFs and miRNAs. A set of TF?miRNA associations was derived from predicted TF binding sites in promoter regions of miRNA genes. Time-lagged expression correlation analysis was utilised to evaluate the TF?miRNA associations. Our analysis identified 12 TFs that potentially play a central role in regulating miRNAs throughout the differentiation process. Six of these 12 TFs (ATF2, E2F3, HOXA4, NFE2L1, SP3, and YY1) have not previously been described to be important for monocytic differentiation. The remaining six TFs are CEBPB, CREB1, ELK1, NFE2L2, RUNX1, and USF2. For several miRNAs (miR-21, miR-155, miR-424, and miR-17-92), we show how their inferred transcriptional regulation impacts monocytic differentiation. Conclusions: The study demonstrates that miRNAs and their transcriptional regulatory control are integral molecular mechanisms during differentiation. Furthermore, it is the first study to decipher on a large-scale, how miRNAs are controlled by TFs during human monocytic differentiation. Subsequently, we have identified 12 candidate key controllers of miRNAs during this differentiation process. 2009 Schmeier et al; licensee Bio

Adropin Contributes to Anti-Atherosclerosis by Suppressing Monocyte-Endothelial Cell Adhesion and Smooth Muscle Cell Proliferation

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Kengo Sato

2018-04-01

Full Text Available Adropin, a peptide hormone expressed in liver and brain, is known to improve insulin resistance and endothelial dysfunction. Serum levels of adropin are negatively associated with the severity of coronary artery disease. However, it remains unknown whether adropin could modulate atherogenesis. We assessed the effects of adropin on inflammatory molecule expression and human THP1 monocyte adhesion in human umbilical vein endothelial cells (HUVECs, foam cell formation in THP1 monocyte-derived macrophages, and the migration and proliferation of human aortic smooth muscle cells (HASMCs in vitro and atherogenesis in Apoe−/− mice in vivo. Adropin was expressed in THP1 monocytes, their derived macrophages, HASMCs, and HUVECs. Adropin suppressed tumor necrosis factor α-induced THP1 monocyte adhesion to HUVECs, which was associated with vascular cell adhesion molecule 1 and intercellular adhesion molecule 1 downregulation in HUVECs. Adropin shifted the phenotype to anti-inflammatory M2 rather than pro-inflammatory M1 via peroxisome proliferator-activated receptor γ upregulation during monocyte differentiation into macrophages. Adropin had no significant effects on oxidized low-density lipoprotein-induced foam cell formation in macrophages. In HASMCs, adropin suppressed the migration and proliferation without inducing apoptosis via ERK1/2 and Bax downregulation and phosphoinositide 3-kinase/Akt/Bcl2 upregulation. Chronic administration of adropin to Apoe−/− mice attenuated the development of atherosclerotic lesions in the aorta, with reduced the intra-plaque monocyte/macrophage infiltration and smooth muscle cell content. Thus, adropin could serve as a novel therapeutic target in atherosclerosis and related diseases.

Anti-vascular endothelial growth factor therapy-induced glioma invasion is associated with accumulation of Tie2-expressing monocytes

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Hossain, Mohammad B.; Conrad, Charles A.; Aldape, Kenneth D.; Fuller, Gregory N.; Marini, Frank C.; Alonso, Marta M.; Idoate, Miguel Angel; Gilbert, Mark R.; Fueyo, Juan; Gomez-Manzano, Candelaria

2014-01-01

The addition of anti-angiogenic therapy to the few treatments available to patients with malignant gliomas was based on the fact that these tumors are highly vascularized and on encouraging results from preclinical and clinical studies. However, tumors that initially respond to this therapy invariably recur with the acquisition of a highly aggressive and invasive phenotype. Although several myeloid populations have been associated to this pattern of recurrence, a specific targetable population has not been yet identified. Here, we present evidence for the accumulation of Tie2-expressing monocytes/macrophages (TEMs) at the tumor/normal brain interface of mice treated with anti-VEGF therapies in regions with heightened tumoral invasion. Furthermore, we describe the presence of TEMs in malignant glioma surgical specimens that recurred after bevacizumab treatment. Our studies showed that TEMs enhanced the invasive properties of glioma cells and secreted high levels of gelatinase enzymatic proteins. Accordingly, Tie2+MMP9+ monocytic cells were consistently detected in the invasive tumor edge upon anti-VEGF therapies. Our results suggest the presence of a specific myeloid/monocytic subpopulation that plays a pivotal role in the mechanism of escape of malignant gliomas from anti-VEGF therapies and therefore constitutes a new cellular target for combination therapies in patients selected for anti-angiogenesis treatment. PMID:24809734

Developmental endothelial locus-1 modulates platelet-monocyte interactions and instant blood-mediated inflammatory reaction in islet transplantation.

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Kourtzelis, Ioannis; Kotlabova, Klara; Lim, Jong-Hyung; Mitroulis, Ioannis; Ferreira, Anaisa; Chen, Lan-Sun; Gercken, Bettina; Steffen, Anja; Kemter, Elisabeth; Klotzsche-von Ameln, Anne; Waskow, Claudia; Hosur, Kavita; Chatzigeorgiou, Antonios; Ludwig, Barbara; Wolf, Eckhard; Hajishengallis, George; Chavakis, Triantafyllos

2016-04-01

Platelet-monocyte interactions are strongly implicated in thrombo-inflammatory injury by actively contributing to intravascular inflammation, leukocyte recruitment to inflamed sites, and the amplification of the procoagulant response. Instant blood-mediated inflammatory reaction (IBMIR) represents thrombo-inflammatory injury elicited upon pancreatic islet transplantation (islet-Tx), thereby dramatically affecting transplant survival and function. Developmental endothelial locus-1 (Del-1) is a functionally versatile endothelial cell-derived homeostatic factor with anti-inflammatory properties, but its potential role in IBMIR has not been previously addressed. Here, we establish Del-1 as a novel inhibitor of IBMIR using a whole blood-islet model and a syngeneic murine transplantation model. Indeed, Del-1 pre-treatment of blood before addition of islets diminished coagulation activation and islet damage as assessed by C-peptide release. Consistently, intraportal islet-Tx in transgenic mice with endothelial cell-specific overexpression of Del-1 resulted in a marked decrease of monocytes and platelet-monocyte aggregates in the transplanted tissues, relative to those in wild-type recipients. Mechanistically, Del-1 decreased platelet-monocyte aggregate formation, by specifically blocking the interaction between monocyte Mac-1-integrin and platelet GPIb. Our findings reveal a hitherto unknown role of Del-1 in the regulation of platelet-monocyte interplay and the subsequent heterotypic aggregate formation in the context of IBMIR. Therefore, Del-1 may represent a novel approach to prevent or mitigate the adverse reactions mediated through thrombo-inflammatory pathways in islet-Tx and perhaps other inflammatory disorders involving platelet-leukocyte aggregate formation.

Magnetic Nanoparticles Conjugated with Peptides Derived from Monocyte Chemoattractant Protein-1 as a Tool for Targeting Atherosclerosis

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Chung-Wei Kao

2018-05-01

Full Text Available Atherosclerosis is a multifactorial inflammatory disease that may progress silently for long period, and it is also widely accepted as the main cause of cardiovascular diseases. To prevent atherosclerotic plaques from generating, imaging early molecular markers and quantifying the extent of disease progression are desired. During inflammation, circulating monocytes leave the bloodstream and migrate into incipient lipid accumulation in the artery wall, following conditioning by local growth factors and proinflammatory cytokines; therefore, monocyte accumulation in the arterial wall can be observed in fatty streaks, rupture-prone plaques, and experimental atherosclerosis. In this work, we synthesized monocyte-targeting iron oxide magnetic nanoparticles (MNPs, which were incorporated with the peptides derived from the chemokine receptor C-C chemokine receptor type 2 (CCR2-binding motif of monocytes chemoattractant protein-1 (MCP-1 as a diagnostic tool for potential atherosclerosis. MCP-1-motif MNPs co-localized with monocytes in in vitro fluorescence imaging. In addition, with MNPs injection in ApoE knockout mice (ApoE KO mice, the well-characterized animal model of atherosclerosis, MNPs were found in specific organs or regions which had monocytes accumulation, especially the aorta of atherosclerosis model mice, through in vivo imaging system (IVIS imaging and magnetic resonance imaging (MRI. We also performed Oil Red O staining and Prussian Blue staining to confirm the co-localization of MCP-1-motif MNPs and atherosclerosis. The results showed the promising potential of MCP-1-motif MNPs as a diagnostic agent of atherosclerosis.

In vitro differentiation of human monocytes to macrophages: change of PDE profile and its relationship to suppression of tumour necrosis factor-α release by PDE inhibitors

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Gantner, Florian; Kupferschmidt, Rochus; Schudt, Christian; Wendel, Albrecht; Hatzelmann, Armin

1997-01-01

During in vitro culture in 10% human AB serum, human peripheral blood monocytes acquire a macrophage-like phenotype. The underlying differentiation was characterized by increased activities of the macrophage marker enzymes unspecific esterase (NaF-insensitive form) and acid phosphatase, as well as by a down-regulation in surface CD14 expression. In parallel, a dramatic change in the phosphodiesterase (PDE) profile became evident within a few days that strongly resembled that previously described for human alveolar macrophages. Whereas PDE1 and PDE3 activities were augmented, PDE4 activity, which represented the major cyclic AMP-hydrolysing activity of peripheral blood monocytes, rapidly declined. Monocytes and monocyte-derived macrophages responded to lipopolysaccharide (LPS) with the release of tumour necrosis factor-α (TNF). In line with the change in CD14 expression, the EC50 value of LPS for induction of TNF release increased from approximately 0.1 ng ml−1 in peripheral blood monocytes to about 2 ng ml−1 in macrophages. Both populations of cells were equally susceptible towards inhibition of TNF release by cyclic AMP elevating agents such as dibutyryl cyclic AMP, prostaglandin E2 (PGE2) or forskolin, which all led to a complete abrogation of TNF production in a concentration-dependent manner and which were more efficient than the glucocorticoid dexamethasone. In monocytes, PDE4 selective inhibitors (rolipram, RP73401) suppressed TNF formation by 80%, whereas motapizone, a PDE3 selective compound, exerted a comparatively weak effect (10–15% inhibition). Combined use of PDE3 plus PDE4 inhibitors resulted in an additive effect and fully abrogated LPS-induced TNF release as did the mixed PDE3/4 inhibitor tolafentrine. In monocyte-derived macrophages, neither PDE3- nor PDE4-selective drugs markedly affected TNF generation when used alone (<15% inhibition), whereas in combination, they led to a maximal inhibition of TNF formation by about 40–50

Endometriosis Leads to an Increased Trefoil Factor 3 Concentration in the Peritoneal Cavity but Does Not Alter Systemic Levels.

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Henze, Diana; Doecke, Wolf-Dietrich; Hornung, Daniela; Agueusop, Inoncent; von Ahsen, Oliver; Machens, Kathrin; Schmitz, Arndt A; Gashaw, Isabella

2017-02-01

This study analyzed whether trefoil factor 3 (TFF3) is locally elevated and correlated with common biomarkers and inflammatory processes in endometriosis. Peritoneal fluid (PF) was obtained from 50 women and serum from 124 women with or without endometriosis. Experimental endometriosis was induced in female C57BL/6 mice by syngeneic transplantation of uterine tissue to the abdominal wall. Levels of TFF3 in PF of women with endometriosis were significantly increased ( P endometriosis: cancer antigen (CA) 125, CA-19-9, interleukin 8, monocyte chemotactic protein 1, and matrix metalloproteinase 7. Serum levels of TFF3 in women were significantly influenced by the menstrual cycle but were independent from disease state. In mice, local TFF3 levels were significantly elevated in early endometriosis (up to 4 weeks after transplantation, P peritoneal cavity in endometriosis and might play a role in disease pathogenesis and its associated inflammatory processes. Furthermore, the results show that TFF3 is regulated through the menstrual cycle. With respect to animal models, syngeneic mouse model does reflect local TFF3 upregulation in the peritoneal cavity affected by endometriosis.

CD14{sup +} monocytes promote the immunosuppressive effect of human umbilical cord matrix stem cells

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Wang, Ding, E-mail: qqhewd@gmail.com [The State Key Laboratory of Experimental Hematology, Institute of Hematology and Hospital of Blood Diseases, Chinese Academy of Medical Sciences and Peking Union of Medical College, 288 Nanjing Road, Tianjin 300020 (China); TEDA Life and Technology Research Center, Institute of Hematology, Chinese Academy of Medical Sciences, TEDA, Tianjin (China); Chen, Ke, E-mail: chenke_59@hotmail.com [The State Key Laboratory of Experimental Hematology, Institute of Hematology and Hospital of Blood Diseases, Chinese Academy of Medical Sciences and Peking Union of Medical College, 288 Nanjing Road, Tianjin 300020 (China); TEDA Life and Technology Research Center, Institute of Hematology, Chinese Academy of Medical Sciences, TEDA, Tianjin (China); Du, Wei Ting, E-mail: duwtpumc@yahoo.com.cn [The State Key Laboratory of Experimental Hematology, Institute of Hematology and Hospital of Blood Diseases, Chinese Academy of Medical Sciences and Peking Union of Medical College, 288 Nanjing Road, Tianjin 300020 (China); Han, Zhi-Bo, E-mail: zhibohan@hotmail.com [The State Key Laboratory of Experimental Hematology, Institute of Hematology and Hospital of Blood Diseases, Chinese Academy of Medical Sciences and Peking Union of Medical College, 288 Nanjing Road, Tianjin 300020 (China); TEDA Life and Technology Research Center, Institute of Hematology, Chinese Academy of Medical Sciences, TEDA, Tianjin (China); Ren, He, E-mail: knifesharp2000@hotmail.com [National Engineering Research Center of Cell Products, AmCellGene Co. Ltd, TEDA, Tianjin (China); Chi, Ying, E-mail: caizhuying@hotmail.com [The State Key Laboratory of Experimental Hematology, Institute of Hematology and Hospital of Blood Diseases, Chinese Academy of Medical Sciences and Peking Union of Medical College, 288 Nanjing Road, Tianjin 300020 (China); TEDA Life and Technology Research Center, Institute of Hematology, Chinese Academy of Medical Sciences, TEDA, Tianjin (China); and others

2010-09-10

Here, the effect of CD14{sup +} monocytes on human umbilical cord matrix stem cell (hUC-MSC)-mediated immunosuppression was studied in vitro. hUC-MSCs exerted a potent inhibitory effect on the proliferation and interferon-{gamma} (IFN-{gamma}) secretion capacities of CD4{sup +} and CD8{sup +} T cells in response to anti-CD3/CD28 stimulation. Transwell co-culture system revealed that the suppressive effect was primarily mediated by soluble factors. Addition of prostaglandin synthesis inhibitors (indomethacin or NS-398) almost completely abrogated the immunosuppression activity of hUC-MSCs, identifying prostaglandin E{sub 2} (PGE{sub 2}) as an important soluble mediator. CD14{sup +} monocytes were found to be able to enhance significantly the immunosuppressive effect of hUC-MSCs in a dose-dependent fashion. Moreover, the inflammatory cytokine IL-1{beta}, either exogenously added or produced by CD14{sup +} monocytes in culture, could trigger expression of high levels of PGE{sub 2} by hUC-MSCs, whereas inclusion of the IL-1 receptor antagonist (IL-1RA) in the culture down-regulated not only PGE{sub 2} expression, but also reversed the promotional effect of CD14{sup +} monocytes and partially restored CD4{sup +} and CD8{sup +} T cell proliferation and IFN-{gamma} secretion. Our data demonstrate an important role of monocytes in the hUC-MSC-induced immunomodulation, which may have important implications in future efforts to explore the clinical potentials of hUC-MSCs.

Neutrophilic nodules in the intestinal walls of Japanese monkeys associated with the neutrophil chemotactic activity of larval extracts and secretions of Oesophagostomum aculeatum.

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Horii, Y; Ishii, A; Owhashi, M; Miyoshi, M; Usui, M

1985-01-01

High neutrophil chemotactic activity was detected in the culture medium from Oesophagostomum aculeatum larvae in vitro using blind-well chambers with Millipore filters, and guinea pig leucocytes as indicator cells. Neutrophil chemotactic activity was also detected in the extract from larval worms in a dose dependent fashion. This activity was detected in the low molecular weight fractions adjacent to a sodium chloride marker by gel filtration on Sephadex G200. These results were further confirmed with monkey neutrophils. The possible role of this activity in the formation of granulomatous lesions rich in neutrophils found in O aculeatum infections in the Japanese monkey is discussed.

Modulation of the expression of chondroitin sulfate proteoglycan in stimulated human monocytes

International Nuclear Information System (INIS)

Uhlin-Hansen, L.; Eskeland, T.; Kolset, S.O.

1989-01-01

Proteoglycan biosynthesis was studied in human monocytes and monocyte-derived macrophages (MDM) after exposure to typical activators of the monocyte/macrophage system: interferon-gamma (IFN-gamma), lipopolysaccharide (LPS), and phorbol 12-myristate 13-acetate (PMA). By morphological examination, both monocytes and MDM were stimulated by these activators. Treatment with IFN-gamma resulted in a slight decrease in the expression of [35S]chondroitin sulfate proteoglycan (CSPG) in both monocytes and MDM, whereas LPS treatment increased the [35S]CSPG expression 1.8 and 2.2 times, respectively. PMA, in contrast, decreased the CSPG expression 0.4 times in monocytes, whereas MDM were stimulated to increase the biosynthesis 1.9 times. An increase in the sulfate density of the chondroitin sulfate chains was evident following differentiation of monocytes into MDM due to the expression of disulfated disaccharide units of the chondroitin sulfate E type (CS-E). However, monocytes exposed to PMA did also express disaccharides of the chondroitin sulfate E type. Furthermore, the expression of CS-E in MDM was increased 2 times following PMA treatment. An inactive phorbol ester, phorbol 12,13-diacetate, did not affect the expression of CS-E in either monocytes or MDM when compared with control cultures, suggesting that protein kinase C-dependent signal pathways may be involved in the regulation of sulfation of CSPG. Exposure to LPS or IFN-gamma did not lead to any changes in the sulfation of the chondroitin sulfate chains

Effects of acute exercise on monocyte subpopulations in metabolic syndrome patients.

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Wonner, Ralph; Wallner, Stefan; Orsó, Evelyn; Schmitz, Gerd

2016-06-10

Acute exercise induces numerous changes in peripheral blood, e.g. counts of leukocytes. CD16 pos monocytes, which play a role in the pathogenesis of arteriosclerosis and the metabolic syndrome (MetS), are among the blood cells with the highest fold increase through exercise. So far no studies have investigated the effect of exercise on the blood cell composition of patients with MetS. Blood cell counts, a wide panel of laboratory tests, as well as lipid and protein content of monocytes and granulocytes were determined in healthy subjects, persons with metabolic risk and MetS patients before and after one minute of exercise at 400 W. Leukocyte counts increased significantly in all groups with CD14 pos CD16 pos monocytes showing the highest fold-change. In MetS patients the fold increase was smaller. They had a higher resting level of CD14 pos CD16 pos monocytes and a lower basal ratio of CD16 neg /CD16 pos monocytes. A similar ratio of these cells was induced in control and risk subjects after exercise. However, absolute counts of mobilized pro-inflammatory monocytes did not differ significantly. Furthermore, we detected a decrease in protein content of monocytes in controls, but not in MetS patients. As strenuous exercise is able to mobilize the same amount of pro-inflammatory monocytes in MetS patients as in healthy persons, the elevated basal level of these cells in MetS patients is likely to be caused by enhanced maturation rather than chronic mobilization. The removal of these monocytes from the endothelium might be part of the beneficial effect of exercise on vascular disease. © 2016 International Clinical Cytometry Society. © 2016 International Clinical Cytometry Society.

A distinguishing gene signature shared by tumor-infiltrating Tie2-expressing monocytes, blood "resident" monocytes, and embryonic macrophages suggests common functions and developmental relationships.

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Pucci, Ferdinando; Venneri, Mary Anna; Biziato, Daniela; Nonis, Alessandro; Moi, Davide; Sica, Antonio; Di Serio, Clelia; Naldini, Luigi; De Palma, Michele

2009-07-23

We previously showed that Tie2-expressing monocytes (TEMs) have nonredundant proangiogenic activity in tumors. Here, we compared the gene expression profile of tumor-infiltrating TEMs with that of tumor-associated macrophages (TAMs), spleen-derived Gr1(+)Cd11b(+) neutrophils/myeloid-derived suppressor cells, circulating "inflammatory" and "resident" monocytes, and tumor-derived endothelial cells (ECs) by quantitative polymerase chain reaction-based gene arrays. TEMs sharply differed from ECs and Gr1(+)Cd11b(+) cells but were highly related to TAMs. Nevertheless, several genes were differentially expressed between TEMs and TAMs, highlighting a TEM signature consistent with enhanced proangiogenic/tissue-remodeling activity and lower proinflammatory activity. We validated these findings in models of oncogenesis and transgenic mice expressing a microRNA-regulated Tie2-GFP reporter. Remarkably, resident monocytes and TEMs on one hand, and inflammatory monocytes and TAMs on the other hand, expressed coordinated gene expression profiles, suggesting that the 2 blood monocyte subsets are committed to distinct extravascular fates in the tumor microenvironment. We further showed that a prominent proportion of embryonic/fetal macrophages, which participate in tissue morphogenesis, expressed distinguishing TEM genes. It is tempting to speculate that Tie2(+) embryonic/fetal macrophages, resident blood monocytes, and tumor-infiltrating TEMs represent distinct developmental stages of a TEM lineage committed to execute physiologic proangiogenic and tissue-remodeling programs, which can be co-opted by tumors.

Chemotactic Activity on Human Neutrophils to Streptococcus mutans

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Tetiana Haniastuti

2013-07-01

Full Text Available Objective: The aim of this study was to evaluate chemotactic activity o neutrophil to S. mutans. Chemotaxis assay was performed in blind well chambers. Materials and Methods: Hanks balanced salt solution (HBSS containing 106 S. mutans,  108 S. mutans, 10-8 M fMLP, or HBSS alone were placed in the lower wells of the chamber and covered with polycorbonate membrane filter. Neutrophils suspension (2x105 cells was then placed in the upper compartment. After incubation for 60 mins at 37ºC in a humidified atmosphere with 5% CO2, the filters were removed and stained with Giemsa. Result: ANOVA revealed statistically significant differences among groups (p<0.05, indicating that S. mutans induced neutrophils chemotaxis. The number of neutrophils migration in response to 108 S. mutans and 106 S. mutans were signifiantly greater compared to fMLP (p<0.05. Conclusion: S. mutans may activate human neutrophils, resulting in the chemotaxis of the neutrophils.DOI: 10.14693/jdi.v16i2.99

Monocyte chemotactic protein-4 (MCP-4/CCL-13) and CC ...

African Journals Online (AJOL)

EL-HAKIM

chronic inflammation and local tissue eosinophilia. Atopic asthma is characterized by a 50-fold increase in the number of eosinophils relative to neutrophils in the bronchial mucosa. This is the result of the cumulative and sequential effects of variable increases in selective eosinophil versus neutrophil migration occurring at ...

The glial scar-monocyte interplay: a pivotal resolution phase in spinal cord repair.

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Ravid Shechter

Full Text Available The inflammatory response in the injured spinal cord, an immune privileged site, has been mainly associated with the poor prognosis. However, recent data demonstrated that, in fact, some leukocytes, namely monocytes, are pivotal for repair due to their alternative anti-inflammatory phenotype. Given the pro-inflammatory milieu within the traumatized spinal cord, known to skew monocytes towards a classical phenotype, a pertinent question is how parenchymal-invading monocytes acquire resolving properties essential for healing, under such unfavorable conditions. In light of the spatial association between resolving (interleukin (IL-10 producing monocytes and the glial scar matrix chondroitin sulfate proteoglycan (CSPG, in this study we examined the mutual relationship between these two components. By inhibiting the de novo production of CSPG following spinal cord injury, we demonstrated that this extracellular matrix, mainly known for its ability to inhibit axonal growth, serves as a critical template skewing the entering monocytes towards the resolving phenotype. In vitro cell culture studies demonstrated that this matrix alone is sufficient to induce such monocyte polarization. Reciprocal conditional ablation of the monocyte-derived macrophages concentrated at the lesion margins, using diphtheria toxin, revealed that these cells have scar matrix-resolving properties. Replenishment of monocytic cell populations to the ablated mice demonstrated that this extracellular remodeling ability of the infiltrating monocytes requires their expression of the matrix-degrading enzyme, matrix metalloproteinase 13 (MMP-13, a property that was found here to be crucial for functional recovery. Altogether, this study demonstrates that the glial scar-matrix, a known obstacle to regeneration, is a critical component skewing the encountering monocytes towards a resolving phenotype. In an apparent feedback loop, monocytes were found to regulate scar resolution. This

Characterization of osteoclasts derived from CD14+ monocytes isolated from peripheral blood

DEFF Research Database (Denmark)

Sørensen, Mette Grøndahl; Henriksen, Kim; Schaller, Sophie

2007-01-01

Bone resorption is solely mediated by osteoclasts. Therefore, a pure osteoclast population is of high interest for the investigation of biological aspects of the osteoclasts, such as the direct effect of growth factors and hormones, as well as for testing and characterizing inhibitors of bone...... resorption. We have established a pure, stable, and reproducible system for purification of human osteoclasts from peripheral blood. We isolated CD14-positive (CD14+) monocytes using anti-CD14-coated beads. After isolation, the monocytes are differentiated into mature osteoclasts by stimulation...... of osteoclast precursors. No expression of osteoclast markers was observed in the absence of RANKL, whereas RANKL dose-dependently induced the expression of cathepsin K, tartrate-resistant acid phosphatase (TRACP), and matrix metallo proteinase (MMP)-9. Furthermore, morphological characterization of the cells...

Bone morphogenetic protein 9 (BMP9) and BMP10 enhance tumor necrosis factor-α-induced monocyte recruitment to the vascular endothelium mainly via activin receptor-like kinase 2.

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Mitrofan, Claudia-Gabriela; Appleby, Sarah L; Nash, Gerard B; Mallat, Ziad; Chilvers, Edwin R; Upton, Paul D; Morrell, Nicholas W

2017-08-18

Bone morphogenetic proteins 9 and 10 (BMP9/BMP10) are circulating cytokines with important roles in endothelial homeostasis. The aim of this study was to investigate the roles of BMP9 and BMP10 in mediating monocyte-endothelial interactions using an in vitro flow adhesion assay. Herein, we report that whereas BMP9/BMP10 alone had no effect on monocyte recruitment, at higher concentrations both cytokines synergized with tumor necrosis factor-α (TNFα) to increase recruitment to the vascular endothelium. The BMP9/BMP10-mediated increase in monocyte recruitment in the presence of TNFα was associated with up-regulated expression levels of E-selectin, vascular cell adhesion molecule (VCAM-1), and intercellular adhesion molecule 1 (ICAM-1) on endothelial cells. Using siRNAs to type I and II BMP receptors and the signaling intermediaries (Smads), we demonstrated a key role for ALK2 in the BMP9/BMP10-induced surface expression of E-selectin, and both ALK1 and ALK2 in the up-regulation of VCAM-1 and ICAM-1. The type II receptors, BMPR-II and ACTR-IIA were both required for this response, as was Smad1/5. The up-regulation of cell surface adhesion molecules by BMP9/10 in the presence of TNFα was inhibited by LDN193189, which inhibits ALK2 but not ALK1. Furthermore, LDN193189 inhibited monocyte recruitment induced by TNFα and BMP9/10. BMP9/10 increased basal IκBα protein expression, but did not alter p65/RelA levels. Our findings suggest that higher concentrations of BMP9/BMP10 synergize with TNFα to induce the up-regulation of endothelial selectins and adhesion molecules, ultimately resulting in increased monocyte recruitment to the vascular endothelium. This process is mediated mainly via the ALK2 type I receptor, BMPR-II/ACTR-IIA type II receptors, and downstream Smad1/5 signaling. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Increase of infiltrating monocytes in the livers of patients with chronic liver diseases.

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Huang, Rui; Wu, Hongyan; Liu, Yong; Yang, Chenchen; Pan, Zhiyun; Xia, Juan; Xiong, Yali; Wang, Guiyang; Sun, Zhenhua; Chen, Jun; Yan, Xiaomin; Zhang, Zhaoping; Wu, Chao

2016-01-01

Infiltrating monocytes have been demonstrated to contribute to tissue damage in experimental models of liver injury and fibrosis. However, less is known about monocyte infiltration in the livers of patients with chronic liver diseases (CLD). In the present study, we demonstrated that CD68+ hepatic macrophages and MAC387+ infiltrating monocytes were significantly increased in the livers of CLD patients with different etiologies as compared with normal liver tissue. In addition, CLD patients with higher inflammatory grading scores had more CD68+ macrophages and MAC387+ monocytes infiltration in their livers compared to those with lower scores. Significantly more MAC387+ infiltrating monocytes were found in the liver tissue of CLD patients with higher fibrotic staging scores compared to those with lower scores. Monocyte chemoattractant protein-1 (MCP-1) expression was significantly increased in the livers of CLD patients with different etiologies. MCP-1 staining scores were significantly positively associated with the numbers of MAC387+ infiltrating monocytes in CLD patients. Taken together, our results demonstrate that infiltrating monocytes may play a pathological role in exacerbating chronic liver inflammation and fibrosis in CLD. MCP-1 may be involved in the monocyte infiltration and progression of liver inflammation and fibrosis in CLD.

Inhibitory Effects of North American Wild Rice on Monocyte Adhesion and Inflammatory Modulators in Low-Density Lipoprotein Receptor-Knockout Mice.

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Moghadasian, Mohammed H; Zhao, Ruozhi; Ghazawwi, Nora; Le, Khuong; Apea-Bah, Franklin B; Beta, Trust; Shen, Garry X

2017-10-18

The present study examined the effects of wild rice on monocyte adhesion, inflammatory and fibrinolytic mediators in low-density lipoprotein receptor-knockout (LDLr-KO) mice. Male LDLr-KO mice received a cholesterol (0.06%, w/w)-supplemented diet with or without white or wild rice (60%, w/w) for 20 weeks. White rice significantly increased monocyte adhesion and abundances of monocyte chemoattractant protein-1, tissue necrosis factor-α, intracellular cell adhesion molecule-1, plasminogen activator inhibitor-1, urokinase plasminogen activator (uPA), and uPA receptor in aortae and hearts of LDLr-KO mice compared to the control diet. Wild rice inhibited monocyte adhesion to the aorta, atherosclerosis, and abundances of the inflammatory and fibrinolytic regulators in the cardiovascular tissue of LDLr-KO mice compared to white rice. White or wild rice did not significantly alter the levels of cholesterol, triglycerides, or antioxidant enzymes in plasma. The anti-atherosclerotic effect of wild rice may result from its inhibition on monocyte adhesion and inflammatory modulators in LDLr-KO mice.

Obese Mexican American children have elevated MCP-1, TNF-alpha, monocyte concentration, and dyslipidemia

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Obesity is an independent risk factor for chronic disease. The prevalence of obesity is especially high among Mexican American children. Peripheral blood monocytes are altered with obesity contributing to elevated systemic inflammation and increased risk of chronic disease. In addition, obesity alte...

Periodontitis-activated monocytes/macrophages cause aortic inflammation

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Miyajima, Shin-ichi; Naruse, Keiko; Kobayashi, Yasuko; Nakamura, Nobuhisa; Nishikawa, Toru; Adachi, Kei; Suzuki, Yuki; Kikuchi, Takeshi; Mitani, Akio; Mizutani, Makoto; Ohno, Norikazu; Noguchi, Toshihide; Matsubara, Tatsuaki

2014-01-01

A relationship between periodontal disease and atherosclerosis has been suggested by epidemiological studies. Ligature-induced experimental periodontitis is an adequate model for clinical periodontitis, which starts from plaque accumulation, followed by inflammation in the periodontal tissue. Here we have demonstrated using a ligature-induced periodontitis model that periodontitis activates monocytes/macrophages, which subsequently circulate in the blood and adhere to vascular endothelial cells without altering the serum TNF-α concentration. Adherent monocytes/macrophages induced NF-κB activation and VCAM-1 expression in the endothelium and increased the expression of the TNF-α signaling cascade in the aorta. Peripheral blood-derived mononuclear cells from rats with experimental periodontitis showed enhanced adhesion and increased NF-κB/VCAM-1 in cultured vascular endothelial cells. Our results suggest that periodontitis triggers the initial pathogenesis of atherosclerosis, inflammation of the vasculature, through activating monocytes/macrophages. PMID:24893991

Curcumin modulates endothelial permeability and monocyte transendothelial migration by affecting endothelial cell dynamics.

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Monfoulet, Laurent-Emmanuel; Mercier, Sylvie; Bayle, Dominique; Tamaian, Radu; Barber-Chamoux, Nicolas; Morand, Christine; Milenkovic, Dragan

2017-11-01

Curcumin is a phenolic compound that exhibits beneficial properties for cardiometabolic health. We previously showed that curcumin reduced the infiltration of immune cells into the vascular wall and prevented atherosclerosis development in mice. This study aimed to investigate the effect of curcumin on monocyte adhesion and transendothelial migration (TEM) and to decipher the underlying mechanisms of these actions. Human umbilical vein endothelial cells (HUVECs) were exposed to curcumin (0.5-1μM) for 3h prior to their activation by Tumor Necrosis Factor alpha (TNF-α). Endothelial permeability, monocyte adhesion and transendothelial migration assays were conducted under static condition and shear stress that mimics blood flow. We further investigated the impact of curcumin on signaling pathways and on the expression of genes using macroarrays. Pre-exposure of endothelial cells to curcumin reduced monocyte adhesion and their transendothelial migration in both static and shear stress conditions. Curcumin also prevented changes in both endothelial permeability and the area of HUVECs when induced by TNF-α. We showed that curcumin modulated the expression of 15 genes involved in the control of cytoskeleton and endothelial junction dynamic. Finally, we showed that curcumin inhibited NF-κB signaling likely through an antagonist interplay with several kinases as suggested by molecular docking analysis. Our findings demonstrate the ability of curcumin to reduce monocyte TEM through a multimodal regulation of the endothelial cell dynamics with a potential benefit on the vascular endothelial function barrier. Copyright © 2017 Elsevier Inc. All rights reserved.

Tie2-Expressing Monocytes Are Associated with Identification and Prognoses of Hepatitis B Virus Related Hepatocellular Carcinoma after Resection

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He, Yi-Feng; Wang, Chao-Qun; Yu, Yao; Qian, Jing; Song, Kang; Sun, Qi-Man; Zhou, Jian

2015-01-01

Background Tie2-expressing monocytes (TEMs) are found in various tumors, involved in forming tumor blood vessels and expressing several important proangiogenic factors. The goals of this study were to evaluate the value of TEMs in diagnosing and predicting the prognosis of hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC). Methods Flow cytometry was performed to identify and count TEMs in peripheral blood monocytes from HCC patients (n = 84) receiving hepatectomy, HBV cirrhotic p...

Prognostic significance of peripheral monocyte count in patients with extranodal natural killer/T-cell lymphoma

International Nuclear Information System (INIS)

Huang, Jia-Jia; Li, Zhi-Ming; Li, Ya-Jun; Xia, Yi; Wang, Yu; Wei, Wen-Xiao; Zhu, Ying-Jie; Lin, Tong-Yu; Huang, Hui-Qiang; Jiang, Wen-Qi

2013-01-01

Extranodal natural killer/T-cell lymphoma (ENKL) has heterogeneous clinical manifestations and prognosis. This study aims to evaluate the prognostic impact of absolute monocyte count (AMC) in ENKL, and provide some immunologically relevant information for better risk stratification in patients with ENKL. Retrospective data from 163 patients newly diagnosed with ENKL were analyzed. The absolute monocyte count (AMC) at diagnosis was analyzed as continuous and dichotomized variables. Independent prognostic factors of survival were determined by Cox regression analysis. The AMC at diagnosis were related to overall survival (OS) and progression-free survival (PFS) in patients with ENKL. Multivariate analysis identified AMC as independent prognostic factors of survival, independent of International Prognostic Index (IPI) and Korean prognostic index (KPI). The prognostic index incorporating AMC and absolute lymphocyte count (ALC), another surrogate factor of immune status, could be used to stratify all 163 patients with ENKL into different prognostic groups. For patients who received chemotherapy followed by radiotherapy (102 cases), the three AMC/ALC index categories identified patients with significantly different survivals. When superimposed on IPI or KPI categories, the AMC/ALC index was better able to identify high-risk patients in the low-risk IPI or KPI category. The baseline peripheral monocyte count is shown to be an effective prognostic indicator of survival in ENKL patients. The prognostic index related to tumor microenvironment might be helpful to identify high-risk patients with ENKL

Prognostic significance of peripheral monocyte count in patients with extranodal natural killer/T-cell lymphoma.

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Huang, Jia-Jia; Li, Ya-Jun; Xia, Yi; Wang, Yu; Wei, Wen-Xiao; Zhu, Ying-Jie; Lin, Tong-Yu; Huang, Hui-Qiang; Jiang, Wen-Qi; Li, Zhi-Ming

2013-05-03

Extranodal natural killer/T-cell lymphoma (ENKL) has heterogeneous clinical manifestations and prognosis. This study aims to evaluate the prognostic impact of absolute monocyte count (AMC) in ENKL, and provide some immunologically relevant information for better risk stratification in patients with ENKL. Retrospective data from 163 patients newly diagnosed with ENKL were analyzed. The absolute monocyte count (AMC) at diagnosis was analyzed as continuous and dichotomized variables. Independent prognostic factors of survival were determined by Cox regression analysis. The AMC at diagnosis were related to overall survival (OS) and progression-free survival (PFS) in patients with ENKL. Multivariate analysis identified AMC as independent prognostic factors of survival, independent of International Prognostic Index (IPI) and Korean prognostic index (KPI). The prognostic index incorporating AMC and absolute lymphocyte count (ALC), another surrogate factor of immune status, could be used to stratify all 163 patients with ENKL into different prognostic groups. For patients who received chemotherapy followed by radiotherapy (102 cases), the three AMC/ALC index categories identified patients with significantly different survivals. When superimposed on IPI or KPI categories, the AMC/ALC index was better able to identify high-risk patients in the low-risk IPI or KPI category. The baseline peripheral monocyte count is shown to be an effective prognostic indicator of survival in ENKL patients. The prognostic index related to tumor microenvironment might be helpful to identify high-risk patients with ENKL.

Chemotactic preferences govern competition and pattern formation in simulated two-strain microbial communities.

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Centler, Florian; Thullner, Martin

2015-01-01

Substrate competition is a common mode of microbial interaction in natural environments. While growth properties play an important and well-studied role in competition, we here focus on the influence of motility. In a simulated two-strain community populating a homogeneous two-dimensional environment, strains competed for a common substrate and only differed in their chemotactic preference, either responding more sensitively to a chemoattractant excreted by themselves or responding more sensitively to substrate. Starting from homogeneous distributions, three possible behaviors were observed depending on the competitors' chemotactic preferences: (i) distributions remained homogeneous, (ii) patterns formed but dissolved at a later time point, resulting in a shifted community composition, and (iii) patterns emerged and led to the extinction of one strain. When patterns formed, the more aggregating strain populated the core of microbial aggregates where starving conditions prevailed, while the less aggregating strain populated the more productive zones at the fringe or outside aggregates, leading to a competitive advantage of the less aggregating strain. The presence of a competitor was found to modulate a strain's behavior, either suppressing or promoting aggregate formation. This observation provides a potential mechanism by which an aggregated lifestyle might evolve even if it is initially disadvantageous. Adverse effects can be avoided as a competitor hinders aggregate formation by a strain which has just acquired this ability. The presented results highlight both, the importance of microbial motility for competition and pattern formation, and the importance of the temporal evolution, or history, of microbial communities when trying to explain an observed distribution.

Distinct RNA transcriptome patterns are potentially associated with angiogenesis in Tie2-expressing monocytes.

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Wang, Xinjing; Dai, Zhiyuan; Wu, Xiaoli; Wang, Kai; Wang, Xipeng

2016-04-10

Tie2-expressing Monocytes (TEMs) were previously identified as a novel subset of monocytes and were believed to have prominent pro-angiogenesis activities in human tumors. While the molecular mechanism of the angiogenesis promoting capacity of TEMs remains unclear. RNA transcriptome pattern, including non-coding RNAs as microRNA (miRNA) and long non-coding RNA (lncRNA), plays important role in cell differentiation and functions. However, little is known about the transcriptome patterns of TEMs, including those non-coding RNAs. We explore the transcriptome of TEMs and the matched monocytes that do not express Tie2 (Tie2(-)monocytes) isolated from peripheral blood of healthy adults employing the Agilent Human miRNA(8*60K,Design ID: 046064)microarray and the Agilent lncRNA Gene Expression(4*180K, Design ID: 042818)microarray. A total of 141 mRNAs, 142 lncRNAs and 75 miRNAs were found dysregulated in TEMs compared to Tie2(-)monocytes. TEMs have the distinct RNA transcriptome patterns according to the Hierarchical clustering and then the gene expression patterns were confirmed by quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR). Functional annotation by Gene Ontology (GO) analyses showed that the up-regulated mRNAs in TEMs were associated to blood vessel remodeling and positive regulation of epithelial cell proliferation, and the up-regulated insulin like growth factor 1(IGF1) mRNA was involved in both pathways. For functional analysis of those dysregulated non-coding RNAs, target genes of the miRNAs were predicted and cis/trans-regulation analysis of the lncRNAs were performed. Copyright © 2016 Elsevier B.V. All rights reserved.

The Role of Monocyte Percentage in Osteoporosis in Male Rheumatic Diseases.

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Su, Yu-Jih; Chen, Chao Tung; Tsai, Nai-Wen; Huang, Chih-Cheng; Wang, Hung-Chen; Kung, Chia-Te; Lin, Wei-Che; Cheng, Ben-Chung; Su, Chih-Min; Hsiao, Sheng-Yuan; Lu, Cheng-Hsien

2017-11-01

Osteoporosis is easily overlooked in male patients, especially in the field of rheumatic diseases mostly prevalent with female patients, and its link to pathogenesis is still lacking. Attenuated monocyte apoptosis from a transcriptome-wide expression study illustrates the role of monocytes in osteoporosis. This study tested the hypothesis that the monocyte percentage among leukocytes could be a biomarker of osteoporosis in rheumatic diseases. Eighty-seven males with rheumatic diseases were evaluated in rheumatology outpatient clinics for bone mineral density (BMD) and surrogate markers, such as routine peripheral blood parameters and autoantibodies. From the total number of 87 patients included in this study, only 15 met the criteria for diagnosis of osteoporosis. Both age and monocyte percentage remained independently associated with the presence of osteoporosis. Steroid dose (equivalent prednisolone dose) was negatively associated with BMD of the hip area and platelet counts were negatively associated with BMD and T score of the spine area. Besides age, monocyte percentage meets the major requirements for osteoporosis in male rheumatic diseases. A higher monocyte percentage in male rheumatic disease patients, aged over 50 years in this study, and BMD study should be considered in order to reduce the risk of osteoporosis-related fractures.

Differential Modulation of Annexin I Binding Sites on Monocytes and Neutrophils

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H. S. Euzger

1999-01-01

Full Text Available Specific binding sites for the anti-inflammatory protein annexin I have been detected on the surface of human monocytes and polymorphonuclear leukocytes (PMN. These binding sites are proteinaceous in nature and are sensitive to cleavage by the proteolytic enzymes trypsin, collagenase, elastase and cathepsin G. When monocytes and PMN were isolated independently from peripheral blood, only the monocytes exhibited constitutive annexin I binding. However PMN acquired the capacity to bind annexin I following co-culture with monocytes. PMN incubation with sodium azide, but not protease inhibitors, partially blocked this process. A similar increase in annexin I binding capacity was also detected in PMN following adhesion to endothelial monolayers. We propose that a juxtacrine activation rather than a cleavage-mediated transfer is involved in this process. Removal of annexin I binding sites from monocytes with elastase rendered monocytes functionally insensitive to full length annexin I or to the annexin I-derived pharmacophore, peptide Ac2-26, assessed as suppression of the respiratory burst. These data indicate that the annexin I binding site on phagocytic cells may have an important function in the feedback control of the inflammatory response and their loss through cleavage could potentiate such responses.

Maturation and demise of human primary monocytes by carbon nanotubes

KAUST Repository

De Nicola, Milena D.; Mirabile Gattia, Daniele; Traversa, Enrico; Ghibelli, Lina

2013-01-01

-competent monocytes by mechanisms related to the presence of large nanoparticle aggregates, suggesting phenomena of bulk toxicity possibly consisting of frustrated phagocytosis. At the same time, MWCNT stimulate adhesion of the phagocytosis-incompetent monocytes

Lymphotoxin-α3 mediates monocyte-endothelial interaction by TNFR I/NF-κB signaling

International Nuclear Information System (INIS)

Suna, Shinichiro; Sakata, Yasuhiko; Shimizu, Masahiko; Nakatani, Daisaku; Usami, Masaya; Matsumoto, Sen; Mizuno, Hiroya; Ozaki, Kouichi; Takashima, Seiji; Takeda, Hiroshi; Tanaka, Toshihiro; Hori, Masatsugu; Sato, Hiroshi

2009-01-01

We recently reported that the single nucleotide polymorphisms of the lymphotoxin-(LT)α gene, a member of the tumor necrosis factor (TNF) family, are closely related to acute myocardial infarction; however, the precise mechanism of LTα signaling in atherogenesis remains unclear. We investigated the role of LTα3, a secreted homotrimer of LTα, in monocyte-endothelial cell adhesion using cultured human umbilical vein endothelial cells (HUVEC). We found that LTα3 induced cell adhesion molecules and activated NF-κB p50 and p65. LTα3 also induced phosphorylation of Akt, phosphorylation and degradation of IκB, nuclear translocation of p65, and increased adhesion of THP1 monocytes to HUVEC. These effects were mediated by TNF receptor (TNFR) I and attenuated by the phosphatidylinositol triphosphate-kinase (PI3K) inhibitors LY294002 and Wortmannin. Thus, LTα3 mediates the monocyte-endothelial interaction via the classical NF-κB pathway following TNFR I/PI3K activation, indicating it may play a role in the development of coronary artery disease.

From human monocytes to genome-wide binding sites--a protocol for small amounts of blood: monocyte isolation/ChIP-protocol/library amplification/genome wide computational data analysis.

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Sebastian Weiterer

Full Text Available Chromatin immunoprecipitation in combination with a genome-wide analysis via high-throughput sequencing is the state of the art method to gain genome-wide representation of histone modification or transcription factor binding profiles. However, chromatin immunoprecipitation analysis in the context of human experimental samples is limited, especially in the case of blood cells. The typically extremely low yields of precipitated DNA are usually not compatible with library amplification for next generation sequencing. We developed a highly reproducible protocol to present a guideline from the first step of isolating monocytes from a blood sample to analyse the distribution of histone modifications in a genome-wide manner.The protocol describes the whole work flow from isolating monocytes from human blood samples followed by a high-sensitivity and small-scale chromatin immunoprecipitation assay with guidance for generating libraries compatible with next generation sequencing from small amounts of immunoprecipitated DNA.

Prion protein induced signaling cascades in monocytes

International Nuclear Information System (INIS)

Krebs, Bjarne; Dorner-Ciossek, Cornelia; Schmalzbauer, Ruediger; Vassallo, Neville; Herms, Jochen; Kretzschmar, Hans A.

2006-01-01

Prion proteins play a central role in transmission and pathogenesis of transmissible spongiform encephalopathies. The cellular prion protein (PrP C ), whose physiological function remains elusive, is anchored to the surface of a variety of cell types including neurons and cells of the lymphoreticular system. In this study, we investigated the response of a mouse monocyte/macrophage cell line to exposure with PrP C fusion proteins synthesized with a human Fc-tag. PrP C fusion proteins showed an attachment to the surface of monocyte/macrophages in nanomolar concentrations. This was accompanied by an increase of cellular tyrosine phosphorylation as a result of activated signaling pathways. Detailed investigations exhibited activation of downstream pathways through a stimulation with PrP fusion proteins, which include phosphorylation of ERK 1,2 and Akt kinase. Macrophages opsonize and present antigenic structures, contact lymphocytes, and deliver cytokines. The findings reported here may become the basis of understanding the molecular function of PrP C in monocytes and macrophages

CD147 and CD98 complex-mediated homotypic aggregation attenuates the CypA-induced chemotactic effect on Jurkat T cells.

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Guo, Na; Zhang, Kui; Lv, Minghua; Miao, Jinlin; Chen, Zhinan; Zhu, Ping

2015-02-01

Homotypic cell aggregation plays important roles in physiological and pathological processes, including embryogenesis, immune responses, angiogenesis, tumor cell invasion and metastasis. CD147 has been implicated in most of these phenomena, and it was identified as a T cell activation-associated antigen due to its obvious up-regulation in activated T cells. However, the explicit function and mechanism of CD147 in T cells have not been fully elucidated. In this study, large and compact aggregates were observed in Jurkat T cells after treatment with the specific CD147 monoclonal antibody HAb18 or after the expression of CD147 was silenced by RNA interference, which indicated an inhibitory effect of CD147 in T cell homotypic aggregation. Knocking down CD147 expression resulted in a significant decrease in CD98, along with prominent cell aggregation, similar to that treated by CD98 and CD147 monoclonal antibodies. Furthermore, decreased cell chemotactic activity was observed following CD147- and CD98-mediated cell aggregation, and increased aggregation was correlated with a decrease in the chemotactic ability of the Jurkat T cells, suggesting that CD147- and CD98-mediated homotypic cell aggregation plays a negative role in T cell chemotaxis. Our data also showed that p-ERK, p-ZAP70, p-CD3ζ and p-LCK were significantly decreased in the CD147- and CD98-knocked down Jurkat T cells, which suggested that decreased CD147- and/or CD98-induced homotypic T cell aggregation and aggregation-inhibited chemotaxis might be associated with these signaling pathways. A role for CD147 in cell aggregation and chemotaxis was further indicated in primary CD4(+) T cells. Similarly, low expression of CD147 in primary T cells induced prominent cell aggregation and this aggregation attenuated primary T cell chemotactic ability in response to CypA. Our results have demonstrated the correlation between homotypic cell aggregation and the chemotactic response of T cells to CypA, and these data

Impact of chronic and acute academic stress on lymphocyte subsets and monocyte function.

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Viktoriya Maydych

Full Text Available This study investigated the effects of a temporally confined naturalistic stressor (academic stress on immune functions. Furthermore, moderating influences of a number of psychological variables were assessed. Five blood samples were obtained from 20 students during an observation period of 8 weeks, starting 4.5 weeks before an exam period up to 1 week following the last exam. The analysis of 45 immune parameters revealed several time-dependent changes attributable to examination stress. We observed a reduction in the absolute numbers of natural killer (NK cells and monocytes in peripheral blood and a shift towards more immature and naïve cells within NK and T cell populations. In addition, IL-6 and TNF-α production by LPS-stimulated monocytes was increased. Psychological variables were grouped by means of factor analyses into two factors. One factor, which was interpreted as an indication of chronic stress, moderated the relationships between academic stress and percentages of mature CD57+ NK cells. This chronic stress factor was also associated with an increase in memory and a decrease in naïve CD8 T cells and increased serum levels of IL-17. The present study identifies important potential psychological mediators of stress-induced changes in specific immunological parameters.

[The effect of isoflurane on the secretion of TNF-alpha and IL-1 beta from LPS-stimulated human peripheral blood monocytes].

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Sato, W; Enzan, K; Masaki, Y; Kayaba, M; Suzuki, M

1995-07-01

The cytokines such as tumor necrosis factor and interleukin-1 secreted from macrophages/monocytes proved to play important roles in the pathogenesis of endotoxemia, severe pancreatitis and other surgical injuries. However, it is still unclear how inhalational anesthetic agents influence the secretion of these cytokines from macrophages/monocytes. We investigated the effects of isoflurane on TNF-alpha and IL-1 beta secretions from human peripheral blood monocytes stimulated by lipopolysaccharide. TNF-alpha and IL-1 beta secretions increased after LPS stimulation and this increase was inhibited by isoflurane in dose-dependent fashion. The inhibitory action of isoflurane disappeared between 1 and 3 hours after stopping isoflurane inhalation. We concluded that isoflurane could inhibit TNF-alpha and IL-1 beta secretions from peripheral blood monocytes stimulated by LPS in a dose-dependent fashion and that the inhibitory action of isoflurane was reversible.

Aliphatic alcohols in spirits inhibit phagocytosis by human monocytes.

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Pál, László; Árnyas, Ervin M; Bujdosó, Orsolya; Baranyi, Gergő; Rácz, Gábor; Ádány, Róza; McKee, Martin; Szűcs, Sándor

2015-04-01

A large volume of alcoholic beverages containing aliphatic alcohols is consumed worldwide. Previous studies have confirmed the presence of ethanol-induced immunosuppression in heavy drinkers, thereby increasing susceptibility to infectious diseases. However, the aliphatic alcohols contained in alcoholic beverages might also impair immune cell function, thereby contributing to a further decrease in microbicidal activity. Previous research has shown that aliphatic alcohols inhibit phagocytosis by granulocytes but their effect on human monocytes has not been studied. This is important as they play a crucial role in engulfment and killing of pathogenic microorganisms and a decrease in their phagocytic activity could lead to impaired antimicrobial defence in heavy drinkers. The aim of this study was to measure monocyte phagocytosis following their treatment with those aliphatic alcohols detected in alcoholic beverages. Monocytes were separated from human peripheral blood and phagocytosis of opsonized zymosan particles by monocytes treated with ethanol and aliphatic alcohols individually and in combination was determined. It was shown that these alcohols could suppress the phagocytic activity of monocytes in a concentration-dependent manner and when combined with ethanol, they caused a further decrease in phagocytosis. Due to their additive effects, it is possible that they may inhibit phagocytosis in a clinically meaningful way in alcoholics and episodic heavy drinkers thereby contribute to their increased susceptibility to infectious diseases. However, further research is needed to address this question.

Mycobacterium leprae alters classical activation of human monocytes in vitro.

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Fallows, Dorothy; Peixoto, Blas; Kaplan, Gilla; Manca, Claudia

2016-01-01

Macrophages play a central role in the pathogenesis of leprosy, caused by Mycobacterium leprae. The polarized clinical presentations in leprosy are associated with differential immune activation. In tuberculoid leprosy, macrophages show a classical activation phenotype (M1), while macrophages in lepromatous disease display characteristics of alternative activation (M2). Bacille Calmette-Guérin (BCG) vaccination, which protects against leprosy, can promote sustained changes in monocyte response to unrelated pathogens and may preferentially direct monocytes towards an M1 protective phenotype. We previously reported that M. leprae can dampen the response of naïve human monocytes to a strong inducer of pro-inflammatory cytokines, such as BCG. Here, we investigated the ability of the pathogen to alter the direction of macrophage polarization and the impact of BCG vaccination on the monocyte response to M. leprae. We show that in vitro exposure of monocytes from healthy donors to M. leprae interferes with subsequent M1 polarization, indicated by lower levels of M1-associated cytokine/chemokines released and reduced expression of M1 cell surface markers. Exposure to M. leprae phenolic glycolipid (PGL) 1, instead of whole bacteria, demonstrated a similar effect on M1 cytokine/chemokine release. In addition, we found that monocytes from 10-week old BCG-vaccinated infants released higher levels of the pro-inflammatory cytokines TNF-α and IL-1β in response to M. leprae compared to those from unvaccinated infants. Exposure to M. leprae has an inhibitory effect on M1 macrophage polarization, likely mediated through PGL-1. By directing monocyte/macrophages preferentially towards M1 activation, BCG vaccination may render the cells more refractory to the inhibitory effects of subsequent M. leprae infection.

Moderate Increase of Indoxyl Sulfate Promotes Monocyte Transition into Profibrotic Macrophages.

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Chiara Barisione

Full Text Available The uremic toxin Indoxyl-3-sulphate (IS, a ligand of Aryl hydrocarbon Receptor (AhR, raises in blood during early renal dysfunction as a consequence of tubular damage, which may be present even when eGFR is normal or only moderately reduced, and promotes cardiovascular damage and monocyte-macrophage activation. We previously found that patients with abdominal aortic aneurysms (AAAs have higher CD14+CD16+ monocyte frequency and prevalence of moderate chronic kidney disease (CKD than age-matched control subjects. Here we aimed to evaluate the IS levels in plasma from AAA patients and to investigate in vitro the effects of IS concentrations corresponding to mild-to-moderate CKD on monocyte polarization and macrophage differentiation.Free IS plasma levels, monocyte subsets and laboratory parameters were evaluated on blood from AAA patients and eGFR-matched controls. THP-1 monocytes, treated with IS 1, 10, 20 μM were evaluated for CD163 expression, AhR signaling and then induced to differentiate into macrophages by PMA. Their phenotype was evaluated both at the stage of semi-differentiated and fully differentiated macrophages. AAA and control sera were similarly used to treat THP-1 monocytes and the resulting macrophage phenotype was analyzed.IS plasma concentration correlated positively with CD14+CD16+ monocytes and was increased in AAA patients. In THP-1 cells, IS promoted CD163 expression and transition to macrophages with hallmarks of classical (IL-6, CCL2, COX2 and alternative phenotype (IL-10, PPARγ, TGF-β, TIMP-1, via AhR/Nrf2 activation. Analogously, AAA sera induced differentiation of macrophages with enhanced IL-6, MCP1, TGF-β, PPARγ and TIMP-1 expression.IS skews monocyte differentiation toward low-inflammatory, profibrotic macrophages and may contribute to sustain chronic inflammation and maladaptive vascular remodeling.

Tie2-Expressing Monocytes Are Associated with Identification and Prognoses of Hepatitis B Virus Related Hepatocellular Carcinoma after Resection.

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He, Yi-Feng; Wang, Chao-Qun; Yu, Yao; Qian, Jing; Song, Kang; Sun, Qi-Man; Zhou, Jian

2015-01-01

Tie2-expressing monocytes (TEMs) are found in various tumors, involved in forming tumor blood vessels and expressing several important proangiogenic factors. The goals of this study were to evaluate the value of TEMs in diagnosing and predicting the prognosis of hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC). Flow cytometry was performed to identify and count TEMs in peripheral blood monocytes from HCC patients (n = 84) receiving hepatectomy, HBV cirrhotic patients (n = 21), benign tumors patients (n = 15) and healthy volunteers (n = 23). Angiopoietin-2 (Ang-2) levels in the plasma were determined by enzyme linked immunosorbent assay. The distribution of TEMs in tumor tissue was observed by immunofluorescence staining. Then we determined the vascular area as a percentage of tumor area (vascular area/tumor area) by immunohistochemical staining. Finally the prognostic significance of TEMs and other clinicopathologic factors was evaluated. Percentage of TEMs in peripheral blood monocytes significantly increased in HCC patients compared with HBV cirrhotic patients and healthy donors (both PTEMs was positively correlated with plasma Ang-2 concentration (PTEMs was significantly higher than that of paratumoral TEMs (PTEMs was associated with poor overall survival (P = 0.043) and a shorter time to recurrence (P = 0.041). Multivariate Cox analysis also revealed that the percentage of TEMs in peripheral blood was an independent factor for HCC patients' prognosis. TEMs may promote angiogenesis in HCC regarding the angiopoietin/Tie2 signal pathway. Percentage of TEMs in peripheral blood monocytes may be applied as a biomarker for identifying HBV-related HCC and predicting the prognosis of these patients after resection.

A simple method for human peripheral blood monocyte Isolation

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Marcos C de Almeida

2000-04-01

Full Text Available We describe a simple method using percoll gradient for isolation of highly enriched human monocytes. High numbers of fully functional cells are obtained from whole blood or buffy coat cells. The use of simple laboratory equipment and a relatively cheap reagent makes the described method a convenient approach to obtaining human monocytes.

Dexamethasone Suppresses Oxysterol-Induced Differentiation of Monocytic Cells

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Yonghae Son

2016-01-01

Full Text Available Oxysterol like 27-hydroxycholesterol (27OHChol has been reported to induce differentiation of monocytic cells into a mature dendritic cell phenotype. We examined whether dexamethasone (Dx affects 27OHChol-induced differentiation using THP-1 cells. Treatment of monocytic cells with Dx resulted in almost complete inhibition of transcription and surface expression of CD80, CD83, and CD88 induced by 27OHChol. Elevated surface levels of MHC class I and II molecules induced by 27OHChol were reduced to basal levels by treatment with Dx. A decreased endocytosis ability caused by 27OHChol was recovered by Dx. We also examined effects of Dx on expression of CD molecules involved in atherosclerosis. Increased levels of surface protein and transcription of CD105, CD137, and CD166 by treatment with 27OHChol were significantly inhibited by cotreatment with Dx. These results indicate that Dx inhibits 27OHChol-induced differentiation of monocytic cells into a mature dendritic cell phenotype and expression of CD molecules whose levels are associated with atherosclerosis. In addition, we examined phosphorylation of AKT induced by 27OHChol and effect of Dx, where cotreatment with Dx inhibited the phosphorylation of AKT. The current study reports that Dx regulates oxysterol-mediated dendritic cell differentiation of monocytic cells.

Evaluating the Use of Monocytes with a Degradable Polyurethane for Vascular Tissue Regeneration

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Battiston, Kyle Giovanni

Monocytes are one of the first cell types present following the implantation of a biomaterial or tissue engineered construct. Depending on the monocyte activation state supported by the biomaterial, monocytes and their derived macrophages (MDMs) can act as positive contributors to tissue regeneration and wound healing, or conversely promote a chronic inflammatory response that leads to fibrous encapsulation and implant rejection. A degradable polar hydrophobic iconic polyurethane (D-PHI) has been shown to reduce pro-inflammatory monocyte/macrophage response compared to tissue culture polystyrene (TCPS), a substrate routinely used for in vitro culture of cells, as well as poly(lactide- co-glycolide) (PLGA), a standard synthetic biodegradable biomaterial in the tissue engineering field. D-PHI has also shown properties suitable for use in a vascular tissue engineering context. In order to understand the mechanism through which D-PHI attenuates pro-inflammatory monocyte response, this thesis investigated the ability of D-PHI to modulate interactions with adsorbed serum proteins and the properties of D-PHI that were important for this activity. D-PHI was shown to regulate protein adsorption in a manner that produced divergent monocyte responses compared to TCPS and PLGA when coated with the serum proteins alpha2-macroglobulin or immunoglobulin G (IgG). In the case of IgG, D-PHI was shown to reduce pro-inflammatory binding site exposure as a function of the material's polar, hydrophobic, and ionic character. Due to the favourable monocyte activation state supported by D-PHI, and the importance of monocytes/macrophages in regulating the response of tissue-specific cell types in vivo, the ability of a D-PHI-stimulated monocyte/macrophage activation state to contribute to modulating the response of vascular smooth muscle cells (VSMCs) in a vascular tissue engineering context was investigated. D-PHI- stimulated monocytes promoted VSMC growth and migration through biomolecule

TREM2 expression in the human brain: a marker of monocyte recruitment?

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Fahrenhold, Marie; Rakic, Sonja; Classey, John; Brayne, Carol; Ince, Paul G; Nicoll, James A R; Boche, Delphine

2017-10-07

Mutation in the triggering receptor expressed on myeloid cells (TREM) 2 gene has been identified as a risk factor for several neurodegenerative diseases including Alzheimer's disease (AD). Experimental studies using animal models of AD have highlighted a number of functions associated with TREM2 and its expression by microglial cells. It has therefore been assumed that this is also the case in humans. However, there is very limited information concerning the cellular expression of TREM2 in the human brain. As part of investigations of microglia using post-mortem resources provided by the Medical Research Council Cognitive Function and Ageing Studies (MRC-CFAS), we immunostained the cerebral cortex of 299 participants for TREM2 using the Sigma antibody HPA010917 and compared with the macrophage/microglial markers Iba1 and CD68. As expected, Iba1 and CD68 labeled microglia and perivascular macrophages. However, in most cases (284/299), the TREM2 antibody labelled monocytes within vascular lumens, but not microglia or perivascular macrophages. In contrast, in 5 out of 6 cases with acute infarcts, TREM2 immunoreaction identified cells within the brain parenchyma interpreted as recruited monocytes. Six cases with old infarcts contained phagocytic foamy macrophages which were CD68-positive but TREM2 negative. Our observations, using the HPA010917 anti-TREM2 antibody, suggest that TREM2 is not expressed by microglia but instead seems to be a marker of recruited monocytes in the human brain. This finding has implications with regards to the role of TREM2 as a risk factor, emphasizing the importance of systemic immune responses in the development and progression of Alzheimer's disease. © 2017 International Society of Neuropathology.

Inhibitory Effects of Red Wine Extracts on Endothelial-Dependent Adhesive Interactions with Monocytes Induced by Oxysterols

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Yuji Naito

2004-01-01

Full Text Available Red wine polyphenolic compounds have been demonstrated to possess antioxidant properties, and several studies have suggested that they might constitute a relevant dietary factor in the protection from coronary heart disease. The aim of the present study is to examine whether red wine extracts (RWE can ameliorate oxysterol-induced endothelial response, and whether inhibition of adhesion molecule expression is involved in monocyte adhesion to endothelial cells. Surface expression and mRNA levels of adhesion molecules (intercellular adhesion molecule 1 and vascular cell adhesion molecule 1 were determined by ELISA and RT-PCR performed on human aortic endothelial cells (HAEC monolayers stimulated with 7b-hydroxycholesterol or 25-hydroxycholesterol. Incubation of HAEC with oxysterols (10 muM increased expression of adhesion molecules in a time-dependent manner. Pretreatment of HAEC with RWE at final concentrations of 1, 10, and 100 ng/ml significantly inhibited the increase of surface protein expression and mRNA levels. Adherence of monocytes to oxysterol-stimulated HAEC was increased compared to that of unstimulated cells. Treatment of HAEC with RWE significantly inhibited adherence of monocytes. These results suggest that RWE works as an anti-atherogenic agent through the inhibition of endothelial-dependent adhesive interactions with monocytes induced by oxysterols

IL-4 induces cAMP and cGMP in human monocytic cells

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B. Dugas

1995-01-01

Full Text Available Human monocytes, preincubated with IFN-γ respond to IL-4 by a cGMP increase through activation of an inducible NO synthase. Here, IL-4 was found to induce an accumulation of cGMP (1 – 3 min and cAMP (20 – 25 min in unstimulated monocytes. This was impaired with NOS inhibitors, but also with EGTA and calcium/calmodulin inhibitors. These results suggest that: (1 IL-4 may stimulate different NOS isoforms in resting and IFN-γ activated monocytes, and (2 cAMP accumulation may be partially dependent on the NO pathway. By RT-PCR, a type III constitutive NOS mRNA was detected in U937 monocytic cells. IL-4 also increased the [Ca2+]i in these cells. Different NOS may thus be expressed in monocytic cells depending on their differentiation and the signals they receive.

Stimulation of the Angiotensin II AT2 Receptor is Anti-inflammatory in Human Lipopolysaccharide-Activated Monocytic Cells

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Menk, Mario; Graw, Jan Adriaan; von Haefen, Clarissa

2015-01-01

and the translational level over course of time. Treatment with C21 attenuated the expression of TNFα, IL-6, and IL-10 after LPS challenge in both cell lines in a time- and dose-dependent manner. We conclude that selective AT2 receptor stimulation acts anti-inflammatory in human monocytes. Modulation of cytokine......Recently, AT2 receptors have been discovered on the surface of human immunocompetent cells such as monocytes. Data on regulative properties of this receptor on the cellular immune response are poor. We hypothesized that direct stimulation of the AT2 receptor mediates anti-inflammatory responses...... in these cells. Human monocytic THP-1 and U937 cells were stimulated with lipopolysaccharide (LPS) and the selective AT2 receptor agonist Compound 21 (C21). Expression of pro- and anti-inflammatory cytokines IL-6, IL-10, tumor necrosis factor-α (TNFα), and IL-1β were analyzed on both the transcriptional...

Cis and trans acting factors involved in human cytomegalovirus experimental and natural latent infection of CD14 (+ monocytes and CD34 (+ cells.

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Cyprian C Rossetto

Full Text Available The parameters involved in human cytomegalovirus (HCMV latent infection in CD14 (+ and CD34 (+ cells remain poorly identified. Using next generation sequencing we deduced the transcriptome of HCMV latently infected CD14 (+ and CD34 (+ cells in experimental as well as natural latency settings. The gene expression profile from natural infection in HCMV seropositive donors closely matched experimental latency models, and included two long non-coding RNAs (lncRNAs, RNA4.9 and RNA2.7 as well as the mRNAs encoding replication factors UL84 and UL44. Chromatin immunoprecipitation assays on experimentally infected CD14 (+ monocytes followed by next generation sequencing (ChIP-Seq were employed to demonstrate both UL84 and UL44 proteins interacted with the latent viral genome and overlapped at 5 of the 8 loci identified. RNA4.9 interacts with components of the polycomb repression complex (PRC as well as with the MIE promoter region where the enrichment of the repressive H3K27me3 mark suggests that this lncRNA represses transcription. Formaldehyde Assisted Isolation of Regulatory Elements (FAIRE, which identifies nucleosome-depleted viral DNA, was used to confirm that latent mRNAs were associated with actively transcribed, FAIRE analysis also showed that the terminal repeat (TR region of the latent viral genome is depleted of nucleosomes suggesting that this region may contain an element mediating viral genome maintenance. ChIP assays show that the viral TR region interacts with factors associated with the pre replication complex and a plasmid subclone containing the HCMV TR element persisted in latently infected CD14 (+ monocytes, strongly suggesting that the TR region mediates viral chromosome maintenance.

Minocycline Inhibition of Monocyte Activation Correlates with Neuronal Protection in SIV NeuroAIDS

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Campbell, Jennifer H.; Burdo, Tricia H.; Autissier, Patrick; Bombardier, Jeffrey P.; Westmoreland, Susan V.; Soulas, Caroline; González, R. Gilberto; Ratai, Eva-Maria; Williams, Kenneth C.

2011-01-01

Background Minocycline is a tetracycline antibiotic that has been proposed as a potential conjunctive therapy for HIV-1 associated cognitive disorders. Precise mechanism(s) of minocycline's functions are not well defined. Methods Fourteen rhesus macaques were SIV infected and neuronal metabolites measured by proton magnetic resonance spectroscopy (1H MRS). Seven received minocycline (4 mg/kg) daily starting at day 28 post-infection (pi). Monocyte expansion and activation were assessed by flow cytometry, cell traffic to lymph nodes, CD16 regulation, viral replication, and cytokine production were studied. Results Minocycline treatment decreased plasma virus and pro-inflammatory CD14+CD16+ and CD14loCD16+ monocytes, and reduced their expression of CD11b, CD163, CD64, CCR2 and HLA-DR. There was reduced recruitment of monocyte/macrophages and productively infected cells in axillary lymph nodes. There was an inverse correlation between brain NAA/Cr (neuronal injury) and circulating CD14+CD16+ and CD14loCD16+ monocytes. Minocycline treatment in vitro reduced SIV replication CD16 expression on activated CD14+CD16+ monocytes, and IL-6 production by monocytes following LPS stimulation. Conclusion Neuroprotective effects of minocycline are due in part to reduction of activated monocytes, monocyte traffic. Mechanisms for these effects include CD16 regulation, reduced viral replication, and inhibited immune activation. PMID:21494695

Adipose Extracellular Matrix/Stromal Vascular Fraction Gel Secretes Angiogenic Factors and Enhances Skin Wound Healing in a Murine Model

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Mingliang Sun

2017-01-01

Full Text Available Mesenchymal stem cells are an attractive cell type for cytotherapy in wound healing. The authors recently developed a novel, adipose-tissue-derived, injectable extracellular matrix/stromal vascular fraction gel (ECM/SVF-gel for stem cell therapy. This study was designed to assess the therapeutic effects of ECM/SVF-gel on wound healing and potential mechanisms. ECM/SVF-gel was prepared for use in nude mouse excisional wound healing model. An SVF cell suspension and phosphate-buffered saline injection served as the control. The expression levels of vascular endothelial growth factor (VEGF, basic fibroblast growth factor (bFGF, and monocyte chemotactic protein-1 (MCP-1 in ECM/SVF-gel were analyzed at different time points. Angiogenesis (tube formation assays of ECM/SVF-gel extracts were evaluated, and vessels density in skin was determined. The ECM/SVF-gel extract promoted tube formation in vitro and increased the expression of the angiogenic factors VEGF and bFGF compared with those in the control. The expression of the inflammatory chemoattractant MCP-1 was high in ECM/SVF-gel at the early stage and decreased sharply during the late stage of wound healing. The potent angiogenic effects exerted by ECM/SVF-gel may contribute to the improvement of wound healing, and these effects could be related to the enhanced inflammatory response in ECM/SVF-gel during the early stage of wound healing.

Sympathetic Release of Splenic Monocytes Promotes Recurring Anxiety Following Repeated Social Defeat.

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McKim, Daniel B; Patterson, Jenna M; Wohleb, Eric S; Jarrett, Brant L; Reader, Brenda F; Godbout, Jonathan P; Sheridan, John F

2016-05-15

Neuroinflammatory signaling may contribute to the pathophysiology of chronic anxiety disorders. Previous work showed that repeated social defeat (RSD) in mice promoted stress-sensitization that was characterized by the recurrence of anxiety following subthreshold stress 24 days after RSD. Furthermore, splenectomy following RSD prevented the recurrence of anxiety in stress-sensitized mice. We hypothesize that the spleen of RSD-exposed mice became a reservoir of primed monocytes that were released following neuroendocrine activation by subthreshold stress. Mice were subjected to subthreshold stress (i.e., single cycle of social defeat) 24 days after RSD, and immune and behavioral measures were taken. Subthreshold stress 24 days after RSD re-established anxiety-like behavior that was associated with egress of Ly6C(hi) monocytes from the spleen. Moreover, splenectomy before RSD blocked monocyte trafficking to the brain and prevented anxiety-like behavior following subthreshold stress. Splenectomy, however, had no effect on monocyte accumulation or anxiety when determined 14 hours after RSD. In addition, splenocytes cultured 24 days after RSD exhibited a primed inflammatory phenotype. Peripheral sympathetic inhibition before subthreshold stress blocked monocyte trafficking from the spleen to the brain and prevented the re-establishment of anxiety in RSD-sensitized mice. Last, β-adrenergic antagonism also prevented splenic monocyte egress after acute stress. The spleen served as a unique reservoir of primed monocytes that were readily released following sympathetic activation by subthreshold stress that promoted the re-establishment of anxiety. Collectively, the long-term storage of primed monocytes in the spleen may have a profound influence on recurring anxiety disorders. Copyright © 2016 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

Aminopeptidase N/CD13 is associated with raft membrane microdomains in monocytes

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Navarrete Santos, A; Roentsch, J; Danielsen, E M

2000-01-01

as in adhesion and cell-cell interactions. Here, we report for the first time that aminopeptidase N/CD13 in monocytes is partially localized in detergent-insoluble membrane microdomains enriched in cholesterol, glycolipids, and glycosylphosphoinositol-anchored proteins, referred to as "rafts." Raft fractions...... of monocytes were characterized by the presence of GM1 ganglioside as raft marker molecule and by the high level of tyrosine-phosphorylated proteins. Furthermore, similar to polarized cells, rafts in monocytic cells lack Na(+), K(+)-ATPase. Cholesterol depletion of monocytes by methyl-beta-cyclodextrin greatly...... reduces raft localization of aminopeptidase N/CD13 without affecting ala-p-nitroanilide cleaving activity of cells....

Autocrine secretion of tumor necrosis factor under the influence of interferon-γ amplifies HLA-DR gene induction in human monocytes

International Nuclear Information System (INIS)

Arenzana-Seisdedos, F.; Mogensen, S.C.; Vuillier, F.; Fiers, W.; Virelizier, J.L.

1988-01-01

Recombinant interferon-γ (IFN-γ) induced HLA-DR gene expression in both U937 and THP-1 human monocytic cell lines, although the former was only very weakly inducible. Combination of recombinant tumor necrosis factor (TNF) and IFN-γ resulted in a synergistic enhancement of DR mRNA and protein induction in both cell lines. TNF alone increased the constitutive expression of the DR gene in THP-1 cells. In the HLA class II-negative U937 cells, TNF used alone was not able to induce DR gene expression. Such a negative result was not due to a lack of TNF receptor expression in U937 cells, since TNF clearly induced HLA class I and TNF gene expression in this cell line. THP-1, but not U937, cells secreted TNF under the influence of IFN-γ. Neutralization of TNF by a specific antibody decreased IFN-γ-induced DR antigen expression in THP-1 cultures. These observations indicate that TNF is not able to directly induce DR gene expression, but rather amplifies ongoing expression of this gene, whether constitutive or induced by IFN-γ. In the two cell lines tested, the level of DR inducibility under the influence of IFN-γ used alone depended on a different inducibility of TNF secretion by IFN-γ. Altogether, the observations indicate that TNF, whether exogenous or endogenously produced under the influence of IFN-γ, amplifies DR gene expression in monocytes, a phenomenon that may provide to such antigen-presenting cells a selective sensitivity to the DR-inducing effects of IFN-γ

CD14(hi)CD16+ monocytes phagocytose antibody-opsonised Plasmodium falciparum infected erythrocytes more efficiently than other monocyte subsets, and require CD16 and complement to do so.

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Zhou, Jingling; Feng, Gaoqian; Beeson, James; Hogarth, P Mark; Rogerson, Stephen J; Yan, Yan; Jaworowski, Anthony

2015-07-07

With more than 600,000 deaths from malaria, mainly of children under five years old and caused by infection with Plasmodium falciparum, comes an urgent need for an effective anti-malaria vaccine. Limited details on the mechanisms of protective immunity are a barrier to vaccine development. Antibodies play an important role in immunity to malaria and monocytes are key effectors in antibody-mediated protection by phagocytosing antibody-opsonised infected erythrocytes (IE). Eliciting antibodies that enhance phagocytosis of IE is therefore an important potential component of an effective vaccine, requiring robust assays to determine the ability of elicited antibodies to stimulate this in vivo. The mechanisms by which monocytes ingest IE and the nature of the monocytes which do so are unknown. Purified trophozoite-stage P. falciparum IE were stained with ethidium bromide, opsonised with anti-erythrocyte antibodies and incubated with fresh whole blood. Phagocytosis of IE and TNF production by individual monocyte subsets was measured by flow cytometry. Ingestion of IE was confirmed by imaging flow cytometry. CD14(hi)CD16+ monocytes phagocytosed antibody-opsonised IE and produced TNF more efficiently than CD14(hi)CD16- and CD14(lo)CD16+ monocytes. Blocking experiments showed that Fcγ receptor IIIa (CD16) but not Fcγ receptor IIa (CD32a) or Fcγ receptor I (CD64) was necessary for phagocytosis. CD14(hi)CD16+ monocytes ingested antibody-opsonised IE when peripheral blood mononuclear cells were reconstituted with autologous serum but not heat-inactivated autologous serum. Antibody-opsonised IE were rapidly opsonised with complement component C3 in serum (t1/2 = 2-3 minutes) and phagocytosis of antibody-opsonised IE was inhibited in a dose-dependent manner by an inhibitor of C3 activation, compstatin. Compared to other monocyte subsets, CD14(hi)CD16+ monocytes expressed the highest levels of complement receptor 4 (CD11c) and activated complement receptor 3 (CD11b) subunits

Granulocyte and monocyte CD11b expression during plasma separation is dependent on complement factor 5 (C5) - an ex vivo study with blood from a C5-deficient individual.

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Hardersen, Randolf; Enebakk, Terje; Christiansen, Dorte; Bergseth, Grethe; Brekke, Ole-Lars; Mollnes, Tom Eirik; Lappegård, Knut Tore; Hovland, Anders

2018-04-01

The aim of the study was to investigate the role of complement factor 5 (C5) in reactions elicited by plasma separation using blood from a C5-deficient (C5D) individual, comparing it to C5-deficient blood reconstituted with C5 (C5DR) and blood from healthy donors. Blood was circulated through an ex vivo plasma separation model. Leukocyte CD11b expression and leukocyte-platelet conjugates were measured by flow cytometry during a 30-min period. Other markers were assessed during a 240-min period. Granulocyte and monocyte CD11b expression did not increase in C5D blood during plasma separation. In C5DR samples granulocytes CD11b expression, measured by mean fluorescence intensity (MFI), increased from 10481 ± 6022 (SD) to 62703 ± 4936, and monocytes CD11b expression changed from 13837 ± 7047 to 40063 ± 713. Granulocyte-platelet conjugates showed a 2.5-fold increase in the C5DR sample compared to the C5D sample. Monocyte-platelet conjugates increased independently of C5. In the C5D samples, platelet count decreased from 210 × 10 9 /L (201-219) (median and range) to 51 × 10 9 /L (50-51), and C3bc increased from 14 CAU/mL (21-7) to 198 CAU/mL (127-269), whereas TCC formation was blocked during plasma separation. In conclusion, up-regulation of granulocyte and monocyte CD11b during plasma separation was C5-dependent. The results also indicate C5 dependency in granulocyte-platelet conjugates formation. © 2018 APMIS. Published by John Wiley & Sons Ltd.

Abnormal monocyte recruitment and collateral artery formation in monocyte chemoattractant protein-1 deficient mice

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Voskuil, Michiel; Hoefer, Imo E.; van Royen, Niels; Hua, Jing; de Graaf, Stijn; Bode, Christoph; Buschmann, Ivo R.; Piek, Jan J.

2004-01-01

Monocyte chemoattractant protein 1 (MCP-1) has been shown to be effective for the stimulation of collateral artery formation in small and large animal models. The availability of a genetic knockout mouse enables evaluation of the importance of the role of MCP-1 in the natural course of collateral

Inflammatory Monocytes Mediate Early and Organ-Specific Innate Defense During Systemic Candidiasis

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Ngo, Lisa Y.; Kasahara, Shinji; Kumasaka, Debra K.; Knoblaugh, Sue E.; Jhingran, Anupam; Hohl, Tobias M.

2014-01-01

Candida albicans is a commensal fungus that can cause systemic disease in patients with breaches in mucosal integrity, indwelling catheters, and defects in phagocyte function. Although circulating human and murine monocytes bind C. albicans and promote inflammation, it remains unclear whether C-C chemokine receptor 2 (CCR2)– and Ly6C-expressing inflammatory monocytes exert a protective or a deleterious function during systemic infection. During murine systemic candidiasis, interruption of CCR2-dependent inflammatory monocyte trafficking into infected kidneys impaired fungal clearance and decreased murine survival. Depletion of CCR2-expressing cells led to uncontrolled fungal growth in the kidneys and brain and demonstrated an essential antifungal role for inflammatory monocytes and their tissue-resident derivatives in the first 48 hours postinfection. Adoptive transfer of purified inflammatory monocytes in depleted hosts reversed the defect in fungal clearance to a substantial extent, indicating a compartmentally and temporally restricted protective function that can be transferred to enhance systemic innate antifungal immunity. PMID:23922372

Dopamine Increases CD14+CD16+ Monocyte Transmigration across the Blood Brain Barrier: Implications for Substance Abuse and HIV Neuropathogenesis.

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Calderon, Tina M; Williams, Dionna W; Lopez, Lillie; Eugenin, Eliseo A; Cheney, Laura; Gaskill, Peter J; Veenstra, Mike; Anastos, Kathryn; Morgello, Susan; Berman, Joan W

2017-06-01

In human immunodeficiency virus-1 (HIV) infected individuals, substance abuse may accelerate the development and/or increase the severity of HIV associated neurocognitive disorders (HAND). It is proposed that CD14 + CD16 + monocytes mediate HIV entry into the central nervous system (CNS) and that uninfected and infected CD14 + CD16 + monocyte transmigration across the blood brain barrier (BBB) contributes to the establishment and propagation of CNS HIV viral reservoirs and chronic neuroinflammation, important factors in the development of HAND. The effects of substance abuse on the frequency of CD14 + CD16 + monocytes in the peripheral circulation and on the entry of these cells into the CNS during HIV neuropathogenesis are not known. PBMC from HIV infected individuals were analyzed by flow cytometry and we demonstrate that the frequency of peripheral blood CD14 + CD16 + monocytes in HIV infected substance abusers is increased when compared to those without active substance use. Since drug use elevates extracellular dopamine concentrations in the CNS, we examined the effects of dopamine on CD14 + CD16 + monocyte transmigration across our in vitro model of the human BBB. The transmigration of this monocyte subpopulation is increased by dopamine and the dopamine receptor agonist, SKF 38393, implicating D1-like dopamine receptors in the increase in transmigration elicited by this neurotransmitter. Thus, elevated extracellular CNS dopamine may be a novel common mechanism by which active substance use increases uninfected and HIV infected CD14 + CD16 + monocyte transmigration across the BBB. The influx of these cells into the CNS may increase viral seeding and neuroinflammation, contributing to the development of HIV associated neurocognitive impairments.

Umbilical Cord-derived Mesenchymal Stem Cells Instruct Monocytes Towards an IL10-producing Phenotype by Secreting IL6 and HGF.

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Deng, Yinan; Zhang, Yingcai; Ye, Linsen; Zhang, Tong; Cheng, Jintao; Chen, Guihua; Zhang, Qi; Yang, Yang

2016-12-05

Human UC-MSCs are regarded as an attractive alternative to BM-MSCs for clinical applications due to their easy preparation, higher proliferation and lower immunogenicity. However, the mechanisms underlying immune suppression by UC-MSCs are still unclear. We studied the mechanism of inhibition by UC-MSCs during the differentiation of monocytes into DCs and focused on the specific source and the role of the involved cytokines. We found that UC-MSCs suppressed monocyte differentiation into DCs and instructed monocytes towards other cell types, with clear decreases in the expression of co-stimulatory molecules, in the secretion of inflammatory factors and in allostimulatory capacity. IL6, HGF and IL10 might be involved in this process because they were detected at higher levels in a coculture system. UC-MSCs produce IL-6 and HGF, and neutralization of IL-6 and HGF reversed the suppressive effect of UC-MSCs. IL10 was not produced by UC-MSCs but was exclusively produced by monocytes after exposure to UC-MSCs, IL-6 or HGF. In summary, we found that the UC-MSC-mediated inhibitory effect was dependent on IL6 and HGF secreted by UC-MSCs and that this effect induced monocyte-derived cells to produce IL10, which might indirectly strengthen the suppressive effect of UC-MSCs.

Amelioration of Glucolipotoxicity-Induced Endoplasmic Reticulum Stress by a “Chemical Chaperone” in Human THP-1 Monocytes

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Raji Lenin

2012-01-01

Full Text Available Chronic ER stress is emerging as a trigger that imbalances a number of systemic and arterial-wall factors and promote atherosclerosis. Macrophage apoptosis within advanced atherosclerotic lesions is also known to increase the risk of atherothrombotic disease. We hypothesize that glucolipotoxicity might mediate monocyte activation and apoptosis through ER stress. Therefore, the aims of this study are (a to investigate whether glucolipotoxicity could impose ER stress and apoptosis in THP-1 human monocytes and (b to investigate whether 4-Phenyl butyric acid (PBA, a chemical chaperone could resist the glucolipotoxicity-induced ER stress and apoptosis. Cells subjected to either glucolipotoxicity or tunicamycin exhibited increased ROS generation, gene and protein (PERK, GRP-78, IRE1α, and CHOP expression of ER stress markers. In addition, these cells showed increased TRPC-6 channel expression and apoptosis as revealed by DNA damage and increased caspase-3 activity. While glucolipotoxicity/tunicamycin increased oxidative stress, ER stress, mRNA expression of TRPC-6, and programmed the THP-1 monocytes towards apoptosis, all these molecular perturbations were resisted by PBA. Since ER stress is one of the underlying causes of monocyte dysfunction in diabetes and atherosclerosis, our study emphasize that chemical chaperones such as PBA could alleviate ER stress and have potential to become novel therapeutics.

Infrared spectroscopic characterization of monocytic microvesicles (microparticles) released upon lipopolysaccharide stimulation.

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Lee, Joonsup; Wen, Beryl; Carter, Elizabeth A; Combes, Valery; Grau, Georges E R; Lay, Peter A

2017-07-01

Microvesicles (MVs) are involved in cell-cell interactions, including disease pathogenesis. Nondestructive Fourier-transform infrared (FTIR) spectra from MVs were assessed as a technique to provide new biochemical insights into a LPS-induced monocyte model of septic shock. FTIR spectroscopy provided a quick method to investigate relative differences in biomolecular content of different MV populations that was complementary to traditional semiquantitative omics approaches, with which it is difficult to provide information on relative changes between classes (proteins, lipids, nucleic acids, carbohydrates) or protein conformations. Time-dependent changes were detected in biomolecular contents of MVs and in the monocytes from which they were released. Differences in phosphatidylcholine and phosphatidylserine contents were observed in MVs released under stimulation, and higher relative concentrations of RNA and α-helical structured proteins were present in stimulated MVs compared with MVs from resting cells. FTIR spectra of stimulated monocytes displayed changes that were consistent with those observed in the corresponding MVs they released. LPS-stimulated monocytes had reduced concentrations of nucleic acids, α-helical structured proteins, and phosphatidylcholine compared with resting monocytes but had an increase in total lipids. FTIR spectra of MV biomolecular content will be important in shedding new light on the mechanisms of MVs and the different roles they play in physiology and disease pathogenesis.-Lee, J., Wen, B., Carter, E. A., Combes, V., Grau, G. E. R., Lay, P. A. Infrared spectroscopic characterization of monocytic microvesicles (microparticles) released upon lipopolysaccharide stimulation. © FASEB.

Human CD68 promoter GFP transgenic mice allow analysis of monocyte to macrophage differentiation in vivo.

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Iqbal, Asif J; McNeill, Eileen; Kapellos, Theodore S; Regan-Komito, Daniel; Norman, Sophie; Burd, Sarah; Smart, Nicola; Machemer, Daniel E W; Stylianou, Elena; McShane, Helen; Channon, Keith M; Chawla, Ajay; Greaves, David R

2014-10-09

The recruitment of monocytes and their differentiation into macrophages at sites of inflammation are key events in determining the outcome of the inflammatory response and initiating the return to tissue homeostasis. To study monocyte trafficking and macrophage differentiation in vivo, we have generated a novel transgenic reporter mouse expressing a green fluorescent protein (GFP) under the control of the human CD68 promoter. CD68-GFP mice express high levels of GFP in both monocyte and embryo-derived tissue resident macrophages in adult animals. The human CD68 promoter drives GFP expression in all CD115(+) monocytes of adult blood, spleen, and bone marrow; we took advantage of this to directly compare the trafficking of bone marrow-derived CD68-GFP monocytes to that of CX3CR1(GFP) monocytes in vivo using a sterile zymosan peritonitis model. Unlike CX3CR1(GFP) monocytes, which downregulate GFP expression on differentiation into macrophages in this model, CD68-GFP monocytes retain high-level GFP expression for 72 hours after differentiation into macrophages, allowing continued cell tracking during resolution of inflammation. In summary, this novel CD68-GFP transgenic reporter mouse line represents a powerful resource for analyzing monocyte mobilization and monocyte trafficking as well as studying the fate of recruited monocytes in models of acute and chronic inflammation. © 2014 by The American Society of Hematology.

Effects of Platelets on Platelet Concentrate Product on the Activation of Human Peripheral Blood Monocyte Cells

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N Sadat Razavi Hoseini

2016-02-01

Full Text Available Introduction: Monocytes can interact with platelets due to their surface molecules such as P-selectin glycoprotein ligand-1 (PSGL-1, and form monocyte-platelet complex. In the present study, the effects of platelets interaction of platelet concentrates (PCs and peripheral blood monocytes were investigated in vitro as a model to predict the probable interactions of these cells and consequently activation of monocytes. Methods: In this experimental study, units of whole blood and PCs were prepared from Tehran Blood Transfusion Center. After isolation of monocytes from the whole blood, these cells were treated with PC- derived platelets. The activation of monocytes was assessed before and after treatment by the analysis of the respiratory burst of monocytes using dihydrorhodamine 123 (DHR-123. The study data were analyzed using the non-parametric test of Wilcoxon. Results: The purity of monocytes was determined as 86.1±2 using NycoPrep method. The respiratory burst of monocytes was increased after exposure with platelets. In fact, the difference was significant when platelets were used on the 5th day of storage (P=0.001. Conclusions: The study findings revealed that platelets have an efficient capacity to stimulate and activate monocytes. The possible involvement of molecules in the interaction of platelet-monocyte demand to be further studied in future.

CD13 is a novel mediator of monocytic/endothelial cell adhesion

DEFF Research Database (Denmark)

Mina-Osorio, Paola; Winnicka, Beata; O'Conor, Catherine

2008-01-01

During inflammation, cell surface adhesion molecules guide the adhesion and migration of circulating leukocytes across the endothelial cells lining the blood vessels to access the site of injury. The transmembrane molecule CD13 is expressed on monocytes and endothelial cells and has been shown...... to mediate homotypic cell adhesion, which may imply a role for CD13 in inflammatory monocyte trafficking. Here, we show that ligation and clustering of CD13 by mAb or viral ligands potently induce myeloid cell/endothelial adhesion in a signal transduction-dependent manner involving monocytic cytoskeletal...... rearrangement and filopodia formation. Treatment with soluble recombinant (r)CD13 blocks this CD13-dependent adhesion, and CD13 molecules from monocytic and endothelial cells are present in the same immunocomplex, suggesting a direct participation of CD13 in the adhesive interaction. This concept...

Differential effects of malignant mesothelioma cells on THP-1 monocytes and macrophages.

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Izzi, Valerio; Chiurchiù, Valerio; D'Aquilio, Fabiola; Palumbo, Camilla; Tresoldi, Ilaria; Modesti, Andrea; Baldini, Patrizia M

2009-02-01

Malignant mesothelioma (MM) is a highly fatal tumor arising from inner body membranes, whose extensive growth is facilitated by its week immunogenicity and by its ability to blunt the immune response which should arise from the huge mass of leukocytes typically infiltrating this tumor. It has been reported that the inflammatory infiltrate found in MM tissues is characterized by a high prevalence of macrophages. Thus, in this work we evaluated the ability of human MM cells to modulate the inflammatory phenotype of human THP-1 monocytes and macrophages, a widely used in vitro model of monocyte/macrophage differentiation. Furthermore, we tested the hypothesis that the exposure to MM cells could alter the differentiation of THP-1 monocytes favoring the development of alternatively activated, tumor-supporting macrophages. Our data prove for the first time that MM cells can polarize monocytes towards an altered inflammatory phenotype and macrophages towards an immunosuppressive phenotype. Moreover, we demonstrate that monocytes cocultivated with MM cells 'keep a memory' of their encounter with the tumor which influences their differentiation to macrophages. On the whole, we provide evidence that MM cells exert distinct, cell-specific effects on monocytes and macrophages. The thorough characterization of such effects may be of a crucial importance for the rational design of new immunotherapeutic protocols.

Activation of the canonical Wnt/β-catenin pathway enhances monocyte adhesion to endothelial cells

International Nuclear Information System (INIS)

Lee, Dong Kun; Nathan Grantham, R.; Trachte, Aaron L.; Mannion, John D.; Wilson, Colleen L.

2006-01-01

Monocyte adhesion to vascular endothelium has been reported to be one of the early processes in the development of atherosclerosis. In an attempt to develop strategies to prevent or delay atherosclerosis progression, we analyzed effects of the Wnt/β-catenin signaling pathway on monocyte adhesion to various human endothelial cells. Adhesion of fluorescein-labeled monocytes to various human endothelial cells was analyzed under a fluorescent microscope. Unlike sodium chloride, lithium chloride enhanced monocyte adhesion to endothelial cells in a dose-dependent manner. We further demonstrated that inhibitors for glycogen synthase kinase (GSK)-3β or proteosome enhanced monocyte-endothelial cell adhesion. Results of semi-quantitative reverse transcriptase polymerase chain reaction (RT-PCR) indicated that activation of Wnt/β-catenin pathway did not change expression levels of mRNA for adhesion molecules. In conclusion, the canonical Wnt/β-catenin pathway enhanced monocyte-endothelial cell adhesion without changing expression levels of adhesion molecules

Isolation of monocytes from leukapheretic products for large-scale GMP-grade generation of cytomegalovirus-specific T-cell lines by means of an automated elutriation device.

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Perseghin, Paolo; D'Amico, Giovanna; Dander, Erica; Gaipa, Giuseppe; Dassi, Maria; Biagi, Ettore; Biondi, Andrea

2008-08-01

Dendritic cells (DC) act as antigen-presenting cells in immune response-mediated mechanisms against malignant cells and/or viral or fungal pathogens. CD14+ monocytes have been so far isolated by techniques of plastic adherence or by using immunomagnetic methods. Here the effectiveness of a commercially available cell separation system (Elutra, Gambro BCT) in the separation of monocytes and the large-scale production of cytomegalovirus (CMV)-specific T-cell lines were investigated. Six mononuclear cell (MNC) collections were processed with the Elutra system. Monocyte-enriched fraction was differentiated into DCs by addition of granulocyte-macrophage-colony-stimulating factor and interleukin (IL)-4. After 6 days of culture, DCs were matured in the presence of interferon (IFN)-gamma, IFN-alpha, IL-1beta, tumor necrosis factor-alpha, and poly(I:C) and pulsed with a pool of 48 MHC Class I and II-binding CMV peptides. Lymphocytes were then stimulated with mature autologous CMV peptide-pulsed DCs. After elutriation, the mean monocyte yield was 0.89 x 10(9) +/- 0.65 x 10(9), with a 51.0 +/- 31.6 percent recovery and a 51.1 +/- 35.4 percent purity. A significant correlation was observed when basal monocyte content was related to the postelutriation recovery (p < 0.0116). More than 60 percent of plated monocytes were differentiated into DCs, which after pulsing with CMV peptides, were able to stimulate a robust enrichment in CMV antigen-specific T cells in all tested samples (mean percentage of pentamer-positive CD8+ cells, 35% compared to the initial 2%). Our findings might be helpful for an appropriate MNC collection, to maximize the efficiency of the elutriation system and subsequently obtain an optimal monocyte-enriched yield for further DC generation and T-cell stimulation.

Phenotype and Function of CD209+ Bovine Blood Dendritic Cells, Monocyte-Derived-Dendritic Cells and Monocyte-Derived Macrophages.

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Kun Taek Park

Full Text Available Phylogenic comparisons of the mononuclear phagocyte system (MPS of humans and mice demonstrate phenotypic divergence of dendritic cell (DC subsets that play similar roles in innate and adaptive immunity. Although differing in phenotype, DC can be classified into four groups according to ontogeny and function: conventional DC (cDC1 and cDC2, plasmacytoid DC (pDC, and monocyte derived DC (MoDC. DC of Artiodactyla (pigs and ruminants can also be sub-classified using this system, allowing direct functional and phenotypic comparison of MoDC and other DC subsets trafficking in blood (bDC. Because of the high volume of blood collections required to study DC, cattle offer the best opportunity to further our understanding of bDC and MoDC function in an outbred large animal species. As reported here, phenotyping DC using a monoclonal antibody (mAb to CD209 revealed CD209 is expressed on the major myeloid population of DC present in blood and MoDC, providing a phenotypic link between these two subsets. Additionally, the present study demonstrates that CD209 is also expressed on monocyte derived macrophages (MoΦ. Functional analysis revealed each of these populations can take up and process antigens (Ags, present them to CD4 and CD8 T cells, and elicit a T-cell recall response. Thus, bDC, MoDC, and MoΦ pulsed with pathogens or candidate vaccine antigens can be used to study factors that modulate DC-driven T-cell priming and differentiation ex vivo.

DPPC regulates COX-2 expression in monocytes via phosphorylation of CREB

International Nuclear Information System (INIS)

Morris, R.H.K.; Tonks, A.J.; Jones, K.P.; Ahluwalia, M.K.; Thomas, A.W.; Tonks, A.; Jackson, S.K.

2008-01-01

The major phospholipid in pulmonary surfactant dipalmitoyl phosphatidylcholine (DPPC) has been shown to modulate inflammatory responses. Using human monocytes, this study demonstrates that DPPC significantly increased PGE 2 (P < 0.05) production by 2.5-fold when compared to untreated monocyte controls. Mechanistically, this effect was concomitant with an increase in COX-2 expression which was abrogated in the presence of a COX-2 inhibitor. The regulation of COX-2 expression was independent of NF-κB activity. Further, DPPC increased the phosphorylation of the cyclic AMP response element binding protein (CREB; an important nuclear transcription factor important in regulating COX-2 expression). In addition, we also show that changing the fatty acid groups of PC (e.g. using L-α-phosphatidylcholine β-arachidonoyl-γ-palmitoyl (PAPC)) has a profound effect on the regulation of COX-2 expression and CREB activation. This study provides new evidence for the anti-inflammatory activity of DPPC and that this activity is at least in part mediated via CREB activation of COX-2

Diesel exhaust particle exposure in vitro alters monocyte differentiation and function.

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Nazia Chaudhuri

Full Text Available Air pollution by diesel exhaust particles is associated with elevated mortality and increased hospital admissions in individuals with respiratory diseases such as asthma and chronic obstructive pulmonary disease. During active inflammation monocytes are recruited to the airways and can replace resident alveolar macrophages. We therefore investigated whether chronic fourteen day exposure to low concentrations of diesel exhaust particles can alter the phenotype and function of monocytes from healthy individuals and those with chronic obstructive pulmonary disease. Monocytes were purified from the blood of healthy individuals and people with a diagnosis of chronic obstructive pulmonary disease. Monocyte-derived macrophages were generated in the presence or absence of diesel exhaust particles and their phenotypes studied through investigation of their lifespan, cytokine generation in response to Toll like receptor agonists and heat killed bacteria, and expression of surface markers. Chronic fourteen day exposure of monocyte-derived macrophages to concentrations of diesel exhaust particles >10 µg/ml caused mitochondrial and lysosomal dysfunction, and a gradual loss of cells over time both in healthy and chronic obstructive pulmonary disease individuals. Chronic exposure to lower concentrations of diesel exhaust particles impaired CXCL8 cytokine responses to lipopolysaccharide and heat killed E. coli, and this phenotype was associated with a reduction in CD14 and CD11b expression. Chronic diesel exhaust particle exposure may therefore alter both numbers and function of lung macrophages differentiating from locally recruited monocytes in the lungs of healthy people and patients with chronic obstructive pulmonary disease.

“Omics” Signatures in Peripheral Monocytes from Women with Low BMD Condition

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Bhavna Daswani

2018-01-01

Full Text Available Postmenopausal osteoporosis (PMO is a result of increased bone resorption compared to formation. Osteoclasts are responsible for bone resorption, which are derived from circulating monocytes that undertake a journey from the blood to the bone for the process of osteoclastogenesis. In recent times, the use of high throughput technologies to explore monocytes from women with low versus high bone density has led to the identification of candidate molecules that may be deregulated in PMO. This review provides a list of molecules in monocytes relevant to bone density which have been identified by “omics” studies in the last decade or so. The molecules in monocytes that are deregulated in low BMD condition may contribute to processes such as monocyte survival, migration/chemotaxis, adhesion, transendothelial migration, and differentiation into the osteoclast lineage. Each of these processes may be crucial to the overall route of osteoclastogenesis and an increase in any/all of these processes can lead to increased bone resorption and subsequently low bone density. Whether these molecules are indeed the cause or effect is an arena currently unexplored.

Synergic production of neutrophil chemotactic activity by colonic epithelial cells and eosinophils.

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Dent, Gordon; Loweth, Sam C; Hasan, Anwar Matar; Leslie, Fiona M

2014-10-01

The presence of eosinophils in the lumen and mucosa of the intestine is characteristic of both ulcerative colitis (UC) and Crohn's disease (CD). There is evidence of eosinophil activation in the intestine during acute inflammatory episodes of these diseases; these episodes are also characterized by an influx of neutrophils, which have the potential to cause extensive tissue damage. We undertook a study to determine whether eosinophils in contact with colonic epithelial cells produce factors that may attract neutrophils in response to immunological stimulation. Neutrophil chemotactic activity (NCA) and concentrations of three neutrophil-attracting CXC chemokines - CXCL1 (Groα), CXCL5 (Ena78) and CXCL8 (IL8) - were measured in supernatants of T84 colonic epithelial cells and blood eosinophils or eosinophil-like myeloid leukaemia cells (AML14.3D10), alone or in combination. Cells were stimulated with serum-opsonized zymosan (OZ) particles. NCA (Peosinophil co-cultures were significantly higher than in the supernatants of either cell type alone. Release of CXCL1 (Peosinophils but not higher than from OZ-stimulated epithelial cells. Eosinophils and colonic epithelial cells exhibit synergy in production of neutrophil chemoattractants in response to immunological stimulation. This may represent a mechanism for exaggerated recruitment of neutrophils to the intestine in response to acute infection in conditions that are characterized by the presence of eosinophils in the bowel. Copyright © 2014 Elsevier GmbH. All rights reserved.

Endogenous pyrogen production by human blood monocytes stimulated by staphylococcal cell wall components.

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Oken, M M; Peterson, P K; Wilkinson, B J

1981-01-01

To determine the properties of Staphylococcus aureus contributing to its pyrogenicity, we compared, in human monocytes, endogenous pyrogen production stimulated by heat-killed S. aureus with that stimulated by purified S. aureus cell walls or by particulate peptidoglycan prepared from the same strain. Peptidoglycan, but not the purified cell wall preparation, was found comparable to S. aureus as an endogenous pyrogen stimulus. This finding was associated with a more effective monocyte phagocytosis of S. aureus and peptidoglycan as compared with that of purified cell walls. Lysostaphin digestion of peptidoglycan markedly reduced its pyrogenicity. To test whether the chemical composition of the ingested particles is important, latex particles were tested as possible stimuli for monocyte endogenous pyrogen release. Although 40 to 68% of monocytes ingested latex particles during the first hour, there was no evidence of endogenous pyrogen activity in the supernatant even when supernatants equivalent to 5.2 X 10(6) monocytes were tested. This study demonstrates that the pyrogenic moiety of the S. aureus cell wall resides in the peptidoglycan component. Phagocytosis is not in itself a pyrogenic stimulus, but rather serves as an effective mechanism to bring about contact between the chemical stimulus and the monocyte.

A fragment of alpha-actinin promotes monocyte/macrophage maturation in vitro.

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Luikart, S; Wahl, D; Hinkel, T; Masri, M; Oegema, T

1999-02-01

Conditioned media (CM) from cultures of HL-60 myeloid leukemia cells grown on extracellular bone marrow matrix contains a factor that induces macrophage-like maturation of HL-60 cells. This factor was purified from the CM of HL-60 cells grown on bone marrow stroma by ammonium sulfate precipitation, then sequential chromatography on DEAE, affi-gel blue affinity, gel exclusion, and wheat germ affinity columns, followed by C-4 reverse phase HPLC, and SDS-PAGE. The maturation promoting activity of the CM was identified in a single 31 kD protein. Amino acid sequence analysis of four internal tryptic peptides of this protein confirmed significant homology with amino acid residues 48-60, 138-147, 215-220, and 221-236 of human cytoskeletal alpha-actinin. An immunoaffinity purified rabbit polyclonal anti-chicken alpha-actinin inhibited the activity of HL-60 conditioned media. A 27 kD amino-terminal fragment of alpha-actinin produced by thermolysin digestion of chicken gizzard alpha-actinin, but not intact alpha-actinin, had maturation promoting activity on several cell types, including blood monocytes, as measured by lysozyme secretion and tartrate-resistant acid phosphatase staining. We conclude that an extracellular alpha-actinin fragment can promote monocyte/macrophage maturation. This represents the first example of a fragment of a cytoskeletal component, which may be released during tissue remodeling and repair, playing a role in phagocyte maturation.

Relative uptake of technetium 99m stannous colloid by neutrophils and monocytes is altered by gram-negative infection

International Nuclear Information System (INIS)

Ramsay, Stuart C.; Maggs, Jacqueline A.; Ketheesan, Natkunam; Norton, Robert; LaBrooy, Justin

2005-01-01

Gram-negative infection alters phagocytic cell function; hence, it could affect phagocytic uptake of inorganic colloids by these cells. Neutrophil and monocyte uptake of technetium 99m stannous colloid ( 99m Tc SnC) in whole blood was measured in 10 patients with gram-negative infection (Burkholderia pseudomallei) and 7 controls. Mean uptake per individual neutrophil was reduced in infection. Uptake per monocyte was not significantly different. Blood from six normal individuals was incubated with lysed B. pseudomallei and colloid, which showed reduced neutrophil uptake, but increased monocyte uptake. These results indicate that uptake of 99m Tc SnC stannous colloid can be used to measure alteration in phagocytic cell function. They suggest that infection with B. pseudomallei is associated with reduced phagocytosis by individual neutrophils, possibly through toxic effects of bacterial products. This could have immunopathogenic consequences for this gram-negative infection and may explain why it responds to granulocyte colony-stimulating factor

Soluble vascular endothelial growth factor (VEGF) receptor-1 inhibits migration of human monocytic THP-1 cells in response to VEGF.

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Zhu, Cansheng; Xiong, Zhaojun; Chen, Xiaohong; Lu, Zhengqi; Zhou, Guoyu; Wang, Dunjing; Bao, Jian; Hu, Xueqiang

2011-08-01

We aimed to investigate the regulation and contribution of vascular endothelial growth factor (VEGF) and sFlt-1(1-3) to human monocytic THP-1 migration. Ad-sFlt-1/FLAG, a recombinant adenovirus carrying the human sFlt-1(1-3) (the first three extracellular domains of FLT-1, the hVEGF receptor-1) gene, was constructed. L929 cells were infected with Ad-sFlt-1/FLAG and the expression of sFlt-1 was detected by immunofluorescent assay and ELISA. Corning(®) Transwell(®) Filter Inserts containing polyethylene terephthalate (PET) membranes with pore sizes of 3 μm were used as an experimental model to simulate THP-1 migration. Five VEGF concentrations (0, 0.1, 1, 10 and 100 ng/ml), four concentrations of sFlt-1(1-3)/FLAG expression supernatants (0.1, 1, 10 and 100 ng/ml), and monocyte chemoattractant protein-1 (MCP-1, 10 ng/ml) were used to test the ability of THP-1 cells to migrate through PET membranes. The sFlt-1(1-3) gene was successfully recombined into Ad-sFlt-1/FLAG. sFlt-1(1-3) was expressed in L929 cells transfected with Ad-sFlt-1/FLAG. THP-1 cell migration increased with increasing concentrations of VEGF, while cell migration decreased with increasing concentrations of sFlt1(1-3)/FLAG. sFlt1(1-3)/FLAG had no effect on MCP-1-induced cell migration. This study demonstrated that VEGF is able to elicit a migratory response in THP-1 cells, and that sFlt-1(1-3) is an effective inhibitor of THP-1 migration towards VEGF.

Characterization of monocyte-derived dendritic cells maturated with IFN-alpha

DEFF Research Database (Denmark)

Svane, I M; Nikolajsen, K; Walter, M R

2006-01-01

Dendritic cells (DC) are promising candidates for cancer immunotherapy. These cells can be generated from peripheral blood monocytes cultured with granulocyte macrophage-colony stimulating factor (GM-CSF) and interleukin-4 (IL-4). In order to obtain full functional capacity, maturation is required......, maturation with IFN-alpha has only a small effect on induction of autologous T-cell stimulatory capacity of the DC. However, an increase in DC allogeneic T-cell stimulatory capacity was observed. These data suggest that IFN-alpha has a potential as a maturation agent used in DC-based cancer vaccine trials...

Direct and indirect radioiodination of protein: comparative study of chemotactic peptide labeling

International Nuclear Information System (INIS)

Lavinas, Tatiana

2004-01-01

The development of simple methods for protein radioiodination have stimulated the use of radioiodinated peptides in vivo. There are two basic methods for labeling proteins with radioiodine: direct labeling, reaction of an electrophilic radioiodine with functional activated groups on protein, like the phenol ring in the tyrosine residue, and the conjugation of a previously radioiodinated molecule to the protein, referred as indirect method. The great problem related to the direct radioiodination of proteins is the in vivo dehalogenation. This problem can be minimized if a non-phenolic prosthetic group is used in the indirect radioiodination of the peptide. The ATE prosthetic group, N-succinimidyl 3-(tri-n-butylstannyl) benzoate, when radioiodinated by electrophilic iododestannilation produces N-succinimidyl 3-[ 123 l/ 131 l] iodine benzoate (SIB) that is subsequently conjugated to the protein by the acylation of the lysine group. There are many radiopharmaceuticals employed in scintigraphic images of infection and inflammation used with some limitations. These limitations stimulated the improvement of a new class of radiopharmaceuticals, the receptor-specific related labeled peptides, as the mediators of the inflammatory response, that presents high affinity by receptors expressed in the inflammation process, and fast clearance from blood and non-target tissues. One of these molecules is the synthetic chemotactic peptide fNleLFNIeYK that presents potent chemotaxis for leukocytes, with high affinity by the receptors presented in polymorphonuclear leukocytes and mononuclear phagocytes. The objective of this work included the synthesis of ATE prosthetic group and comparative radioiodination of the chemotactic peptide fNleLFNIeYK by direct and indirect methods, with radiochemical purity determination and evaluation of in vivo and in vitro stability of the compounds. This work presented an original contribution in the comparative biological distribution studies of the

Glucose transporter expression differs between bovine monocyte and macrophage subsets and is influenced by milk production.

Science.gov (United States)

Eger, M; Hussen, J; Koy, M; Dänicke, S; Schuberth, H-J; Breves, G

2016-03-01

The peripartal period of dairy cows is characterized by negative energy balance and higher incidences of infectious diseases such as mastitis or metritis. With the onset of lactation, milk production is prioritized and large amounts of glucose are transported into the mammary gland. Decreased overall energy availability might impair the function of monocytes acting as key innate immune cells, which give rise to macrophages and dendritic cells and link innate and adaptive immunity. Information on glucose requirements of bovine immune cells is rare. Therefore, this study aims to evaluate glucose transporter expression of the 3 bovine monocyte subsets (classical, intermediate, and nonclassical monocytes) and monocyte-derived macrophages and to identify influences of the peripartal period. Blood samples were either collected from nonpregnant healthy cows or from 16 peripartal German Holstein cows at d -14, +7, and +21 relative to parturition. Quantitative real-time PCR was applied to determine mRNA expression of glucose transporters (GLUT) 1, GLUT3, and GLUT4 in monocyte subsets and monocyte-derived macrophages. The low GLUT1 and GLUT3 expression in nonclassical monocytes was unaltered during differentiation into macrophages, whereas in classical and intermediate monocytes GLUT expression was downregulated. Alternatively activated M2 macrophages consumed more glucose compared with classically activated M1 macrophages. The GLUT4 mRNA was only detectable in unstimulated macrophages. Neither monocytes nor macrophages were insulin responsive. In the peripartum period, monocyte GLUT1 and GLUT3 expression and the GLUT3/GLUT1 ratio were negatively correlated with lactose production. The high-affinity GLUT3 transporter appears to be the predominant glucose transporter on bovine monocytes and macrophages, especially in the peripartal period when blood glucose levels decline. Glucose transporter expression in monocytes is downregulated as a function of lactose production, which

Umbilical Cord-derived Mesenchymal Stem Cells Instruct Monocytes Towards an IL10-producing Phenotype by Secreting IL6 and HGF

Science.gov (United States)

Deng, Yinan; Zhang, Yingcai; Ye, Linsen; Zhang, Tong; Cheng, Jintao; Chen, Guihua; Zhang, Qi; Yang, Yang

2016-01-01

Human UC-MSCs are regarded as an attractive alternative to BM-MSCs for clinical applications due to their easy preparation, higher proliferation and lower immunogenicity. However, the mechanisms underlying immune suppression by UC-MSCs are still unclear. We studied the mechanism of inhibition by UC-MSCs during the differentiation of monocytes into DCs and focused on the specific source and the role of the involved cytokines. We found that UC-MSCs suppressed monocyte differentiation into DCs and instructed monocytes towards other cell types, with clear decreases in the expression of co-stimulatory molecules, in the secretion of inflammatory factors and in allostimulatory capacity. IL6, HGF and IL10 might be involved in this process because they were detected at higher levels in a coculture system. UC-MSCs produce IL-6 and HGF, and neutralization of IL-6 and HGF reversed the suppressive effect of UC-MSCs. IL10 was not produced by UC-MSCs but was exclusively produced by monocytes after exposure to UC-MSCs, IL-6 or HGF. In summary, we found that the UC-MSC-mediated inhibitory effect was dependent on IL6 and HGF secreted by UC-MSCs and that this effect induced monocyte-derived cells to produce IL10, which might indirectly strengthen the suppressive effect of UC-MSCs. PMID:27917866

Purification of monocytes from cryopreserved mobilized apheresis products by elutriation with the Elutra device.

Science.gov (United States)

Lemarie, Claude; Sugaye, Romina; Kaur, Indreshpaul; Taga, Tim; Chabannon, Christian; Schuyler, Robert; Mcmannis, John

2007-01-10

The Elutra biomedical device allows semi-automatic enrichment of monocytes by elutriation, using a single-use, closed and cGMP compliant tubing set, in a cost effective way. The procedure has been validated using fresh apheresis products from nonmobilized donors. We here evaluated the possibility of using Elutra to enrich monocytes from frozen/thawed apheresis products collected from mobilized healthy donors. Frozen apheresis products from 6 G CSF mobilized donors were thawed and used in 16 elutriation procedures. We compared the recovery and purity of enriched monocytes using different buffer compositions and elutriation profiles. Elutriated monocytes were cultured to generate mature dendritic cells (DCs). Depending in part of the initial granulocyte contamination in the apheresis product, the use of Desoxyribo Nuclease (DNAse) to avoid aggregation, was needed through only the initial steps or throughout the elutriation process. The average monocyte recovery was 85+/-31%. The average purity was 73+/-9%. The recovery of mature DC at d8 of culture was 20+/-6% of the input monocyte numbers. We conclude that Elutra allows the purification of monocytes from thawed mobilized apheresis. It requires no pre-processing of the cell product before elutriation, and allows the generation of phenotypically mature DC in quantities that are compatible with a clinical use.

DMPD: Monocyte/macrophage traffic in HIV and SIV encephalitis. [Dynamic Macrophage Pathway CSML Database

Lifescience Database Archive (English)

Full Text Available 12960230 Monocyte/macrophage traffic in HIV and SIV encephalitis. Kim WK, Corey S, ...Alvarez X, Williams K. J Leukoc Biol. 2003 Nov;74(5):650-6. Epub 2003 Aug 11. (.png) (.svg) (.html) (.csml) Show Monocyte/macrophage... traffic in HIV and SIV encephalitis. PubmedID 12960230 Title Monocyte/macrophage tr

Statins attenuate polymethylmethacrylate-mediated monocyte activation.

LENUS (Irish Health Repository)

Laing, Alan J

2012-02-03

BACKGROUND: Periprosthetic osteolysis precipitates aseptic loosening of components, increases the risk of periprosthetic fracture and, through massive bone loss, complicates revision surgery and ultimately is the primary cause for failure of joint arthroplasty. The anti-inflammatory properties of HMG-CoA reductase inhibitors belonging to the statin family are well recognized. We investigated a possible role for status in initiating the first stage of the osteolytic cycle, namely monocytic activation. METHODS: We used an in vitro model of the human monocyte\\/macrophage inflammatory response to poly-methylmethacrylate (PMMA) particles after pretreat-ing cells with cerivastatin, a potent member of the statin family. Cell activation based upon production of TNF-alpha and MCP-1 cytokines was analyzed and the intracellular Raf-MEK-ERK signal transduction pathway was evaluated using western blot analysis, to identify its role in cell activation and in any cerivastatin effects observed. RESULTS: We found that pretreatment with cerivastatin significantly abrogates the production of inflammatory cytokines TNF-alpha and MCP-1 by human monocytes in response to polymethylmethacrylate particle activation. This inflammatory activation and attenuation appear to be mediated through the intracellular Raf-MEK-ERK pathway. INTERPRETATION: We propose that by intervening at the upstream activation stage, subsequent osteoclast activation and osteolysis can be suppressed. We believe that the anti-inflammatory properties of statins may potentially play a prophylactic role in the setting of aseptic loosening, and in so doing increase implant longevity.

Nonclassical Ly6C− Monocytes Drive the Development of Inflammatory Arthritis in Mice

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Alexander V. Misharin

2014-10-01

Full Text Available Different subsets and/or polarized phenotypes of monocytes and macrophages may play distinct roles during the development and resolution of inflammation. Here, we demonstrate in a murine model of rheumatoid arthritis that nonclassical Ly6C− monocytes are required for the initiation and progression of sterile joint inflammation. Moreover, nonclassical Ly6C− monocytes differentiate into inflammatory macrophages (M1, which drive disease pathogenesis and display plasticity during the resolution phase. During the development of arthritis, these cells polarize toward an alternatively activated phenotype (M2, promoting the resolution of joint inflammation. The influx of Ly6C− monocytes and their subsequent classical and then alternative activation occurs without changes in synovial tissue-resident macrophages, which express markers of M2 polarization throughout the course of the arthritis and attenuate joint inflammation during the initiation phase. These data suggest that circulating Ly6C− monocytes recruited to the joint upon injury orchestrate the development and resolution of autoimmune joint inflammation.

Ureaplasma Species Differentially Modulate Pro- and Anti-Inflammatory Cytokine Responses in Newborn and Adult Human Monocytes Pushing the State Toward Pro-Inflammation

Science.gov (United States)

Glaser, Kirsten; Silwedel, Christine; Fehrholz, Markus; Waaga-Gasser, Ana M.; Henrich, Birgit; Claus, Heike; Speer, Christian P.

2017-01-01

Background: Ureaplasma species have been associated with chorioamnionitis and preterm birth and have been implicated in the pathogenesis of neonatal short and long-term morbidity. However, being mostly commensal bacteria, controversy remains on the pro-inflammatory capacity of Ureaplasma. Discussions are ongoing on the incidence and impact of prenatal, perinatal, and postnatal infection. The present study addressed the impact of Ureaplasma isolates on monocyte-driven inflammation. Methods: Cord blood monocytes of term neonates and adult monocytes, either native or LPS-primed, were cultured with Ureaplasma urealyticum (U. urealyticum) serovar 8 (Uu8) and Ureaplasma parvum serovar 3 (Up3). Using qRT-PCR, cytokine flow cytometry, and multi-analyte immunoassay, we assessed mRNA and protein expression of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-8, IL-12p40, IL-10, and IL-1 receptor antagonist (IL-1ra) as well as Toll-like receptor (TLR) 2 and TLR4. Results: Uu8 and Up3 induced mRNA expression and protein release of TNF-α, IL-1β and IL-8 in term neonatal and adult monocytes (p Ureaplasma-stimulated cells paralleled those results. Ureaplasma-induced cytokine levels did not significantly differ from LPS-mediated levels except for lower intracellular IL-1β in adult monocytes (Uu8: p ureaplasmas did not induce IL-12p40 response and promoted lower amounts of anti-inflammatory IL-10 and IL-1ra than LPS, provoking a cytokine imbalance more in favor of pro-inflammation (IL-1β/IL-10, IL-8/IL-10 and IL-8/IL-1ra: p Ureaplasma isolates in human monocytes. Stimulating pro-inflammatory cytokine responses while hardly inducing immunomodulatory and anti-inflammatory cytokines, ureaplasmas might push monocyte immune responses toward pro-inflammation. Inhibition of LPS-induced cytokines in adult monocytes in contrast to sustained inflammation in term neonatal monocytes indicates a differential modulation of host immune responses to a second stimulus. Modification of

DMPD: LPS induction of gene expression in human monocytes. [Dynamic Macrophage Pathway CSML Database

Lifescience Database Archive (English)

Full Text Available 11257452 LPS induction of gene expression in human monocytes. Guha M, Mackman N. Ce...ll Signal. 2001 Feb;13(2):85-94. (.png) (.svg) (.html) (.csml) Show LPS induction of gene expression in human... monocytes. PubmedID 11257452 Title LPS induction of gene expression in human monocytes. Authors Guha M, Ma

Toxicity of nanotitanium dioxide (TiO2-NP) on human monocytes and their mitochondria.

Science.gov (United States)

Ghanbary, Fatemeh; Seydi, Enaytollah; Naserzadeh, Parvaneh; Salimi, Ahmad

2018-03-01

The effect of nanotitanium dioxide (TiO 2 -NP) in human monocytes is still unknown. Therefore, an understanding of probable cytotoxicity of TiO 2 -NP on human monocytes and underlining the mechanisms involved is of significant interest. The aim of this study was to assess the cytotoxicity of TiO 2 -NP on human monocytes. Using biochemical and flow cytometry assessments, we demonstrated that addition of TiO 2 -NP at 10 μg/ml concentration to monocytes induced cytotoxicity following 12 h. The TiO 2 -NP-induced cytotoxicity on monocytes was associated with intracellular reactive oxygen species (ROS) generation, mitochondrial membrane potential (MMP) collapse, lysosomal membrane injury, lipid peroxidation, and depletion of glutathione. According to our results, TiO 2 -NP triggers oxidative stress and organelles damages in monocytes which are important cells in defense against foreign agents. Finally, our findings suggest that use of antioxidants and mitochondrial/lysosomal protective agents could be of benefit for the people in the exposure with TiO 2 -NP.

DMPD: Shaping of monocyte and macrophage function by adenosine receptors. [Dynamic Macrophage Pathway CSML Database

Lifescience Database Archive (English)

Full Text Available 17056121 Shaping of monocyte and macrophage function by adenosine receptors. Hasko ...tml) (.csml) Show Shaping of monocyte and macrophage function by adenosine receptors. PubmedID 17056121 Titl...e Shaping of monocyte and macrophage function by adenosine receptors. Authors Has

Virulent Type A Francisella tularensis actively suppresses cytokine responses in human monocytes

Science.gov (United States)

Gillette, Devyn D.; Curry, Heather M.; Cremer, Thomas; Ravneberg, David; Fatehchand, Kavin; Shah, Prexy A.; Wewers, Mark D.; Schlesinger, Larry S.; Butchar, Jonathan P.; Tridandapani, Susheela; Gavrilin, Mikhail A.

2014-01-01

Background: Human monocyte inflammatory responses differ between virulent and attenuated Francisella infection. Results: A mixed infection model showed that the virulent F. tularensis Schu S4 can attenuate inflammatory cytokine responses to the less virulent F. novicida in human monocytes. Conclusion: F. tularensis dampens inflammatory response by an active process. Significance: This suppression may contribute to enhanced pathogenicity of F. tularensis. Francisella tularensis is a Gram-negative facultative bacterium that can cause the disease tularemia, even upon exposure to low numbers of bacteria. One critical characteristic of Francisella is its ability to dampen or subvert the host immune response. Previous work has shown that monocytes infected with highly virulent F. tularensis subsp. tularensis strain Schu S4 responded with a general pattern of quantitatively reduced pro-inflammatory signaling pathway genes and cytokine production in comparison to those infected with the less virulent related F. novicida. However, it has been unclear whether the virulent Schu S4 was merely evading or actively suppressing monocyte responses. By using mixed infection assays with F. tularensis and F. novicida, we show that F. tularensis actively suppresses monocyte pro-inflammatory responses. Additional experiments show that this suppression occurs in a dose-dependent manner and is dependent upon the viability of F. tularensis. Importantly, F. tularensis was able to suppress pro-inflammatory responses to earlier infections with F. novicida. These results lend support that F. tularensis actively dampens human monocyte responses and this likely contributes to its enhanced pathogenicity. PMID:24783062

Measurement of the unfolded protein response (UPR) in monocytes.

LENUS (Irish Health Repository)

Carroll, Tomás P

2011-01-01

In mammalian cells, the primary function of the endoplasmic reticulum (ER) is to synthesize and assemble membrane and secreted proteins. As the main site of protein folding and posttranslational modification in the cell, the ER operates a highly conserved quality control system to ensure only correctly assembled proteins exit the ER and misfolded and unfolded proteins are retained for disposal. Any disruption in the equilibrium of the ER engages a multifaceted intracellular signaling pathway termed the unfolded protein response (UPR) to restore normal conditions in the cell. A variety of pathological conditions can induce activation of the UPR, including neurodegenerative disorders such as Parkinson\\'s disease, metabolic disorders such as atherosclerosis, and conformational disorders such as cystic fibrosis. Conformational disorders are characterized by mutations that modify the final structure of a protein and any cells that express abnormal protein risk functional impairment. The monocyte is an important and long-lived immune cell and acts as a key immunological orchestrator, dictating the intensity and duration of the host immune response. Monocytes expressing misfolded or unfolded protein may exhibit UPR activation and this can compromise the host immune system. Here, we describe in detail methods and protocols for the examination of UPR activation in peripheral blood monocytes. This guide should provide new investigators to the field with a broad understanding of the tools required to investigate the UPR in the monocyte.

Measurement of the unfolded protein response (UPR) in monocytes.

LENUS (Irish Health Repository)

Carroll, Tomas P

2012-02-01

In mammalian cells, the primary function of the endoplasmic reticulum (ER) is to synthesize and assemble membrane and secreted proteins. As the main site of protein folding and posttranslational modification in the cell, the ER operates a highly conserved quality control system to ensure only correctly assembled proteins exit the ER and misfolded and unfolded proteins are retained for disposal. Any disruption in the equilibrium of the ER engages a multifaceted intracellular signaling pathway termed the unfolded protein response (UPR) to restore normal conditions in the cell. A variety of pathological conditions can induce activation of the UPR, including neurodegenerative disorders such as Parkinson\\'s disease, metabolic disorders such as atherosclerosis, and conformational disorders such as cystic fibrosis. Conformational disorders are characterized by mutations that modify the final structure of a protein and any cells that express abnormal protein risk functional impairment. The monocyte is an important and long-lived immune cell and acts as a key immunological orchestrator, dictating the intensity and duration of the host immune response. Monocytes expressing misfolded or unfolded protein may exhibit UPR activation and this can compromise the host immune system. Here, we describe in detail methods and protocols for the examination of UPR activation in peripheral blood monocytes. This guide should provide new investigators to the field with a broad understanding of the tools required to investigate the UPR in the monocyte.

Moderate restriction of macrophage-tropic human immunodeficiency virus type 1 by SAMHD1 in monocyte-derived macrophages.

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Taya, Kahoru; Nakayama, Emi E; Shioda, Tatsuo

2014-01-01

Macrophage-tropic human immunodeficiency virus type 1 (HIV-1) strains are able to grow to high titers in human monocyte-derived macrophages. However, it was recently reported that cellular protein SAMHD1 restricts HIV-1 replication in human cells of the myeloid lineage, including monocyte-derived macrophages. Here we show that degradation of SAMHD1 in monocyte-derived macrophages was associated with moderately enhanced growth of the macrophage-tropic HIV-1 strain. SAMHD1 degradation was induced by treating target macrophages with vesicular stomatitis virus glycoprotein-pseudotyped human immunodeficiency virus type 2 (HIV-2) particles containing viral protein X. For undifferentiated monocytes, HIV-2 particle treatment allowed undifferentiated monocytes to be fully permissive for productive infection by the macrophage-tropic HIV-1 strain. In contrast, untreated monocytes were totally resistant to HIV-1 replication. These results indicated that SAMHD1 moderately restricts even a macrophage-tropic HIV-1 strain in monocyte-derived macrophages, whereas the protein potently restricts HIV-1 replication in undifferentiated monocytes.

A human coronavirus responsible for the common cold massively kills dendritic cells but not monocytes.

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Mesel-Lemoine, Mariana; Millet, Jean; Vidalain, Pierre-Olivier; Law, Helen; Vabret, Astrid; Lorin, Valérie; Escriou, Nicolas; Albert, Matthew L; Nal, Béatrice; Tangy, Frédéric

2012-07-01

Human coronaviruses are associated with upper respiratory tract infections that occasionally spread to the lungs and other organs. Although airway epithelial cells represent an important target for infection, the respiratory epithelium is also composed of an elaborate network of dendritic cells (DCs) that are essential sentinels of the immune system, sensing pathogens and presenting foreign antigens to T lymphocytes. In this report, we show that in vitro infection by human coronavirus 229E (HCoV-229E) induces massive cytopathic effects in DCs, including the formation of large syncytia and cell death within only few hours. In contrast, monocytes are much more resistant to infection and cytopathic effects despite similar expression levels of CD13, the membrane receptor for HCoV-229E. While the differentiation of monocytes into DCs in the presence of granulocyte-macrophage colony-stimulating factor and interleukin-4 requires 5 days, only 24 h are sufficient for these cytokines to sensitize monocytes to cell death and cytopathic effects when infected by HCoV-229E. Cell death induced by HCoV-229E is independent of TRAIL, FasL, tumor necrosis factor alpha, and caspase activity, indicating that viral replication is directly responsible for the observed cytopathic effects. The consequence of DC death at the early stage of HCoV-229E infection may have an impact on the early control of viral dissemination and on the establishment of long-lasting immune memory, since people can be reinfected multiple times by HCoV-229E.

Gas6 Promotes Inflammatory (CCR2hiCX3CR1lo) Monocyte Recruitment in Venous Thrombosis.

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Laurance, Sandrine; Bertin, François-René; Ebrahimian, Talin; Kassim, Yusra; Rys, Ryan N; Lehoux, Stéphanie; Lemarié, Catherine A; Blostein, Mark D

2017-07-01

Coagulation and inflammation are inter-related. Gas6 (growth arrest-specific 6) promotes venous thrombosis and participates to inflammation through endothelial-innate immune cell interactions. Innate immune cells can provide the initiating stimulus for venous thrombus development. We hypothesize that Gas6 promotes monocyte recruitment during venous thrombosis. Deep venous thrombosis was induced in wild-type and Gas6-deficient (-/-) mice using 5% FeCl 3 and flow reduction in the inferior vena cava. Total monocyte depletion was achieved by injection of clodronate before deep venous thrombosis. Inflammatory monocytes were depleted using an anti-C-C chemokine receptor type 2 (CCR2) antibody. Similarly, injection of an anti-chemokine ligand 2 (CCL2) antibody induced CCL2 depletion. Flow cytometry and immunofluorescence were used to characterize the monocytes recruited to the thrombus. In vivo, absence of Gas6 was associated with a reduction of monocyte recruitment in both deep venous thrombosis models. Global monocyte depletion by clodronate leads to smaller thrombi in wild-type mice. Compared with wild type, the thrombi from Gas6 -/- mice contain less inflammatory (CCR2 hi CX 3 CR1 lo ) monocytes, consistent with a Gas6-dependent recruitment of this monocyte subset. Correspondingly, selective depletion of CCR2 hi CX 3 CR1 lo monocytes reduced the formation of venous thrombi in wild-type mice demonstrating a predominant role of the inflammatory monocytes in thrombosis. In vitro, the expression of both CCR2 and CCL2 were Gas6 dependent in monocytes and endothelial cells, respectively, impacting monocyte migration. Moreover, Gas6-dependent CCL2 expression and monocyte migration were mediated via JNK (c-Jun N-terminal kinase). This study demonstrates that Gas6 specifically promotes the recruitment of inflammatory CCR2 hi CX 3 CR1 lo monocytes through the regulation of both CCR2 and CCL2 during deep venous thrombosis. © 2017 American Heart Association, Inc.

The effect of very-low-calorie diet on mRNA expression of inflammation-related genes in subcutaneous adipose tissue and peripheral monocytes of obese patients with type 2 diabetes mellitus.

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Mraz, M; Lacinova, Z; Drapalova, J; Haluzikova, D; Horinek, A; Matoulek, M; Trachta, P; Kavalkova, P; Svacina, S; Haluzik, M

2011-04-01

Low-grade inflammation links obesity, type 2 diabetes mellitus (T2DM), and cardiovascular diseases. To explore the expression profile of genes involved in inflammatory pathways in adipose tissue and peripheral monocytes (PM) of obese patients with and without T2DM at baseline and after dietary intervention. Two-week intervention study with very-low-calorie diet (VLCD). University hospital. Twelve obese females with T2DM, 8 obese nondiabetic females (OB) and 15 healthy age-matched females. Two weeks of VLCD (2500 kJ/d). Metabolic parameters, circulating cytokines, hormones, and mRNA expression of 39 genes in sc adipose tissue (SCAT) and PM. Both T2DM and OB group had significantly increased serum concentrations of circulating proinflammatory factors (C-reactive protein, TNFα, IL-6, IL-8), mRNA expression of macrophage antigen CD68 and proinflammatory chemokines (CCL-2, -3, -7, -8, -17, -22) in SCAT and complementary chemokine receptors (CCR-1, -2, -3, -5) and other proinflammatory receptors (toll-like receptor 2 and 4, TNF receptor superfamily 1A and 1B, IL-6R) in PM, with OB group showing less pronounced chemoattracting and proinflammatory profile compared to T2DM group. In T2DM patients VLCD decreased body weight, improved metabolic profile, and decreased mRNA expression of up-regulated CCRs in PM and chemokines [CCL 8, chemokine (C-X-C motif) ligand 10] in SCAT. VLCD markedly increased mRNA expression of T-lymphocyte attracting chemokine CCL-17 in SCAT. Obese patients with and without T2DM have increased mRNA expression of chemotactic and proinflammatory factors in SCAT and expression of corresponding receptors in PM. Two weeks of VLCD significantly improved this profile in T2DM patients.

Microbial translocation is associated with increased monocyte activation and dementia in AIDS patients.

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Petronela Ancuta

2008-06-01

Full Text Available Elevated plasma lipopolysaccharide (LPS, an indicator of microbial translocation from the gut, is a likely cause of systemic immune activation in chronic HIV infection. LPS induces monocyte activation and trafficking into brain, which are key mechanisms in the pathogenesis of HIV-associated dementia (HAD. To determine whether high LPS levels are associated with increased monocyte activation and HAD, we obtained peripheral blood samples from AIDS patients and examined plasma LPS by Limulus amebocyte lysate (LAL assay, peripheral blood monocytes by FACS, and soluble markers of monocyte activation by ELISA. Purified monocytes were isolated by FACS sorting, and HIV DNA and RNA levels were quantified by real time PCR. Circulating monocytes expressed high levels of the activation markers CD69 and HLA-DR, and harbored low levels of HIV compared to CD4(+ T-cells. High plasma LPS levels were associated with increased plasma sCD14 and LPS-binding protein (LBP levels, and low endotoxin core antibody levels. LPS levels were higher in HAD patients compared to control groups, and were associated with HAD independently of plasma viral load and CD4 counts. LPS levels were higher in AIDS patients using intravenous heroin and/or ethanol, or with Hepatitis C virus (HCV co-infection, compared to control groups. These results suggest a role for elevated LPS levels in driving monocyte activation in AIDS, thereby contributing to the pathogenesis of HAD, and provide evidence that cofactors linked to substance abuse and HCV co-infection influence these processes.

Sperm from sneaker male squids exhibit chemotactic swarming to CO₂.

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Hirohashi, Noritaka; Alvarez, Luis; Shiba, Kogiku; Fujiwara, Eiji; Iwata, Yoko; Mohri, Tatsuma; Inaba, Kazuo; Chiba, Kazuyoshi; Ochi, Hiroe; Supuran, Claudiu T; Kotzur, Nico; Kakiuchi, Yasutaka; Kaupp, U Benjamin; Baba, Shoji A

2013-05-06

Behavioral traits of sperm are adapted to the reproductive strategy that each species employs. In polyandrous species, spermatozoa often form motile clusters, which might be advantageous for competing with sperm from other males. Despite this presumed advantage for reproductive success, little is known about how sperm form such functional assemblies. Previously, we reported that males of the coastal squid Loligo bleekeri produce two morphologically different euspermatozoa that are linked to distinctly different mating behaviors. Consort and sneaker males use two distinct insemination sites, one inside and one outside the female's body, respectively. Here, we show that sperm release a self-attracting molecule that causes only sneaker sperm to swarm. We identified CO2 as the sperm chemoattractant and membrane-bound flagellar carbonic anhydrase as its sensor. Downstream signaling results from the generation of extracellular H(+), intracellular acidosis, and recovery from acidosis. These signaling events elicit Ca(2+)-dependent turning behavior, resulting in chemotactic swarming. These results illuminate the bifurcating evolution of sperm underlying the distinct fertilization strategies of this species. Copyright © 2013 Elsevier Ltd. All rights reserved.

Regulation of EMMPRIN (CD147) on monocyte subsets in patients with symptomatic coronary artery disease.

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Sturhan, Henrik; Ungern-Sternberg, Saskia N I v; Langer, Harald; Gawaz, Meinrad; Geisler, Tobias; May, Andreas E; Seizer, Peter

2015-06-01

The role of individual monocyte subsets in inflammatory cardiovascular diseases is insufficiently understood. Although the Extracellular Matrix Metalloproteinase Inducer (EMMPRIN) regulates important processes for inflammation such as MMP-release, its expression and regulation on monocyte subsets has not been characterized. In this clinical study, blood was obtained from 80 patients with stable coronary artery disease (CAD), 49 with acute myocardial infarction (AMI) and 34 healthy controls. Monocytes were divided into 3 subsets: CD14(++)CD16(-) (low), CD14(++)CD16(+) (intermediate), CD14(+)CD16(++) (high) according to phenotypic markers analyzed by flow cytometry. Surface expression of EMMPRIN was evaluated and compared with CD36 and CD47 expression. In all patients, EMMPRIN expression was significantly different among monocyte subsets with the highest expression on "classical" CD14(++)CD16(-) monocytes. EMMPRIN was upregulated on all monocyte subsets in patients with AMI as compared to patients with stable CAD. Notably, neither CD47 nor CD36 revealed a significant difference in patients with AMI compared to patients with stable CAD. EMMPRIN could serve as a marker for classical monocytes, which is upregulated in patients with acute myocardial infarction. Copyright © 2015 Elsevier Ltd. All rights reserved.

Identification of Therapeutic Targets of Inflammatory Monocyte Recruitment to Modulate the Allogeneic Injury to Donor Cornea

OpenAIRE

Lapp, T.; Zaher, S. S.; Haas, C. T.; Becker, D. L.; Thrasivoulou, C.; Chain, B. M.; Larkin, D. F. P.; Noursadeghi, M.

2015-01-01

Purpose: We sought to test the hypothesis that monocytes contribute to the immunopathogenesis of corneal allograft rejection and identify therapeutic targets to inhibit monocyte recruitment. Methods: Monocytes and proinflammatory mediators within anterior chamber samples during corneal graft rejection were quantified by flow cytometry and multiplex protein assays. Lipopolysaccharide or IFN-γ stimulation of monocyte-derived macrophages (MDMs) was used to generate inflammatory conditioned me...

Antioxidants from diet or supplements do not alter inflammatory markers in adults with cardiovascular disease risk. A pilot randomized controlled trial.

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Dewell, Antonella; Tsao, Philip; Rigdon, Joseph; Gardner, Christopher D

2018-02-01

Antioxidants have been reported to have anti-inflammatory effects, but there is a lack of research comparing food to supplement antioxidant sources. The aim of this study was to determine if increases in intake of foods naturally rich in antioxidants would lower blood levels of inflammatory markers more than consuming antioxidant supplements among adults with cardiovascular disease risk factors. Eighty-eight generally healthy adults with ≥1 elevated risk factor for cardiovascular disease were randomized in a single-blind (diets)/double-blind (supplements), parallel-group study for 8 weeks. Participants consumed (1) usual diet and placebo pills (n = 29), (2) usual diet and antioxidant supplements (n = 29), or (3) antioxidant-rich foods closely matched to antioxidant content of supplements and placebo (n = 30). Usual diet combined with antioxidant supplements or increased antioxidant-rich food intake was designed to approximately double daily habitual antioxidant intake. Antioxidant pills included carotenoids, mixed tocopherols, vitamin C, and selenium. Fasting blood samples were analyzed for inflammatory marker concentrations of interleukin-6, monocyte chemotactic protein-1, and soluble intercellular adhesion molecule-1. Participants in the intervention groups successfully doubled most antioxidants as verified by diet records and elevated blood concentrations in treatment groups. Baseline levels of inflammatory markers for the entire study group were 110 ± 65 pg/mL for monocyte chemotactic protein-1, 0.9 ± 0.7 pg/mL for interleukin-6, and 217 ± 56 ng/mL for soluble intercellular adhesion molecule-1 (means ± standard deviation) and did not differ by treatment arm. After 8 weeks, there were no significant within-group changes or between-group 8-week change differences in inflammatory marker concentrations. In conclusion, no beneficial effects were detected on the inflammatory markers investigated in response to antioxidants from foods or supplements. Copyright �

Novel ex vivo culture method for human monocytes uses shear flow to prevent total loss of transendothelial diapedesis function.

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Tsubota, Yoshiaki; Frey, Jeremy M; Raines, Elaine W

2014-01-01

Monocyte recruitment to inflammatory sites and their transendothelial migration into tissues are critical to homeostasis and pathogenesis of chronic inflammatory diseases. However, even short-term suspension culture of primary human monocytes leads to phenotypic changes. In this study, we characterize the functional effects of ex vivo monocyte culture on the steps involved in monocyte transendothelial migration. Our data demonstrate that monocyte diapedesis is impaired by as little as 4 h culture, and the locomotion step is subsequently compromised. After 16 h in culture, monocyte diapedesis is irreversibly reduced by ∼90%. However, maintenance of monocytes under conditions mimicking physiological flow (5-7.5 dyn/cm²) is sufficient to reduce diapedesis impairment significantly. Thus, through the application of shear during ex vivo culture of monocytes, our study establishes a novel protocol, allowing functional analyses of monocytes not currently possible under static culture conditions. These data further suggest that monocyte-based therapeutic applications may be measurably improved by alteration of ex vivo conditions before their use in patients.

Binding of recombinant HIV coat protein gp120 to human monocytes

International Nuclear Information System (INIS)

Finbloom, D.S.; Hoover, D.L.; Meltzer, M.S.

1991-01-01

Inasmuch as the exact level of CD4 Ag expression on macrophages is controversial and because HIV may interact with macrophages in a manner different from that on T cells, we analyzed the binding of gp120 to freshly isolated and cultured monocytes. rgp120 was iodinated using the lactoperoxidase method to a sp. act. of 600 Ci/mmol. Highly purified monocytes (greater than 90%) were isolated from the leukapheresed blood of normal volunteers by Ficoll-Hypaque sedimentation followed by countercurrent centrifugal elutriation and cultured 7 days in DMEM supplemented with 1000 U/ml macrophage CSF in 10% human serum. Whereas MOLT/4 cells consistently bound freshly prepared 125I-rgp120 at 80% specificity with 5100 +/- 700 mol/cell, MCSF cultured monocytes bound rgp120 at only 0 to 20% specificity and 420 +/- 200 mol/cell. Most of the radioactivity bound by these cells could not be blocked by the addition of unlabeled rgp120. In contrast, the U937 myeloid cell line bound rgp120 with 50% specificity and about 2500 mol/cell. Whereas the antibody OKT4a (anti-CD4) blocked 80% of the binding on MOLT/4 cells and 50% on U937 cells, binding was only inhibited on the average of 6% on cultured monocytes. When soluble rCD4 was used as an inhibitor, binding to MOLT/4 cells was blocked by 80%. In contrast, binding to cultured monocytes was inhibited by 28%. HIV infectivity was blocked by similar concentrations of OKT4a. These observations suggest that although most binding of gp120 to cultured monocytes is not to the CD4 determinant, several hundred molecules do bind to a CD4-like molecule which promotes virus entry and replication

DYSFUNCTION OF MONOCYTES AND DENDRITIC CELLS IN PATIENTS WITH PREMATURE OVARIAN FAILURE

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HOEK, A; VAN KASTEREN, Y; DE HAAN-MEULMAN, M; SCHOEMAKER, J; DREXHAGE, HA

1993-01-01

PROBLEM: Due to the presence of ovarian antibodies it has been suggested that premature ovarian failure (POF) belongs to the autoimmune endocrinopathies. Monocytes and the monocyte-derived dendritic cells play a prominent role in the initial stages of endocrine autoimmune reactions: the accumulation

Alcohol Enhances HIV Infection of Cord Blood Monocyte-Derived Macrophages

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Mastrogiannis, Dimitrios S.; Wang, Xu; Dai, Min; Li, Jieliang; Wang, Yizhong; Zhou, Yu; Sakarcan, Selin; Peña, Juliet Crystal; Ho, Wenzhe

2014-01-01

Alcohol consumption or alcohol abuse is common among pregnant HIV+ women and has been identified as a potential behavioral risk factor for the transmission of HIV. In this study, we examined the impact of alcohol on HIV infection of cord blood monocyte-derived macrophages (CBMDM). We demonstrated that alcohol treatment of CBMDM significantly enhanced HIV infection of CBMDM. Investigation of the mechanisms of alcohol action on HIV demonstrated that alcohol inhibited the expression of several HIV restriction factors, including anti-HIV microRNAs, APOBEC3G and APOBEC3H. Additionally, alcohol also suppressed the expression of IFN regulatory factor 7 (IRF-7) and retinoic acid-inducible gene I (RIG-I), an intracellular sensor of viral infection. The suppression of these IFN regulatory factors was associated with reduced expression of type I IFN. These experimental findings suggest that maternal alcohol consumption may facilitate HIV infection, promoting vertical transmission of HIV. PMID:25053361

Generation of dendritic cells for immunotherapy is minimally impaired by granulocytes in the monocyte preparation.

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ten Brinke, Anja; Karsten, Miriam L; Dieker, Miranda C; Zwaginga, Jaap Jan; Vrielink, Hans; Marieke van Ham, S

2006-01-01

The growing number of clinical studies, using monocyte-derived DC therapy, requires protocols where a sufficient number of dendritic cell (DCs) are produced according to current Good Manufacturing Practice guidelines. Therefore, a closed culture system for the generation of DCs is inevitable. One cost-effective way to isolate monocytes directly from leukapheresis material in a closed system is by elutriation with the Elutra cell separation system. In the Elutra, granulocytes co-purify with the monocytes. Therefore, we studied if and to what extent the presence of granulocytes in a monocyte product affects the generation of mature DCs. The presence of up to 16% granulocytes in the monocyte product had no significant effects on the quality of the DCs formed. The presence of higher granulocyte percentages, however, gradually altered DC quality. In this respect, the presence of higher number of granulocytes induced significant lower migratory capacity of the DCs and lower expression levels of CD80, CD40 and CD86. No effects were observed on the DC yield, cytokine production or the stimulatory capacity of the DCs in MLR. In conclusion, the presence of 20-30% granulocytes in a monocyte product has no major influence on the quality of the DCs generated from monocytes. Therefore, the Elutra is a suitable closed system apparatus to separate monocytes from other blood components for the generation of DCs, even from leukapheresis material which contains a high number of granulocytes.

Pharmacodynamic Monitoring of Tacrolimus-based Immunosuppression in CD14+ Monocytes after Kidney Transplantation

NARCIS (Netherlands)

N.M. Kannegieter (Nynke); D.A. Hesselink (Dennis); M. Dieterich (Marjolein); G.N. de Graav (Gretchen); R. Kraaijeveld (Rens); A.T. Rowshani (Ajda); P.J. Leenen (Pieter); C.C. Baan (Carla)

2017-01-01

markdownabstractBackground: Monocytes significantly contribute to ischemia-reperfusion injury and allograft rejection after kidney transplantation. However, the knowledge about the effects of immunosuppressive drugs on monocyte activation is limited. Conventional pharmacokinetic methods for

Cinnamic Acid Is Partially Involved in Propolis Immunomodulatory Action on Human Monocytes

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Bruno José Conti

2013-01-01

Full Text Available Propolis is a beehive product used in traditional medicine due to its biological properties. It shows a complex chemical composition including phenolics, such as cinnamic acid (Ci. The mechanisms of action of propolis have been the subject of research recently; however, the involvement of Ci on propolis activity was not investigated on immune cells. Ci effects were evaluated on human monocytes, assessing the expression of Toll-like receptors (TLRs, HLA-DR, and CD80. Cytokine production (TNF-α and IL-10 and the fungicidal activity of monocytes were evaluated as well. Data showed that Ci downregulated TLR-2, HLA-DR, and CD80 and upregulated TLR-4 expression by human monocytes. High concentrations of Ci inhibited both TNF-α and IL-10 production, whereas the same concentrations induced a higher fungicidal activity against Candida albicans. TNF-α and IL-10 production was decreased by blocking TLR-4, while the fungicidal activity of monocytes was not affected by blocking TLRs. These results suggest that Ci modulated antigen receptors, cytokine production, and the fungicidal activity of human monocytes depending on concentration, and TLR-4 may be involved in its mechanism of action. Ci seemed to be partially involved in propolis activities.

Interaction studies reveal specific recognition of an anti-inflammatory polyphosphorhydrazone dendrimer by human monocytes.

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Ledall, Jérémy; Fruchon, Séverine; Garzoni, Matteo; Pavan, Giovanni M; Caminade, Anne-Marie; Turrin, Cédric-Olivier; Blanzat, Muriel; Poupot, Rémy

2015-11-14

Dendrimers are nano-materials with perfectly defined structure and size, and multivalency properties that confer substantial advantages for biomedical applications. Previous work has shown that phosphorus-based polyphosphorhydrazone (PPH) dendrimers capped with azabisphosphonate (ABP) end groups have immuno-modulatory and anti-inflammatory properties leading to efficient therapeutic control of inflammatory diseases in animal models. These properties are mainly prompted through activation of monocytes. Here, we disclose new insights into the molecular mechanisms underlying the anti-inflammatory activation of human monocytes by ABP-capped PPH dendrimers. Following an interdisciplinary approach, we have characterized the physicochemical and biological behavior of the lead ABP dendrimer with model and cell membranes, and compared this experimental set of data to predictive computational modelling studies. The behavior of the ABP dendrimer was compared to the one of an isosteric analog dendrimer capped with twelve azabiscarboxylate (ABC) end groups instead of twelve ABP end groups. The ABC dendrimer displayed no biological activity on human monocytes, therefore it was considered as a negative control. In detail, we show that the ABP dendrimer can bind both non-specifically and specifically to the membrane of human monocytes. The specific binding leads to the internalization of the ABP dendrimer by human monocytes. On the contrary, the ABC dendrimer only interacts non-specifically with human monocytes and is not internalized. These data indicate that the bioactive ABP dendrimer is recognized by specific receptor(s) at the surface of human monocytes.

Functional Defects in Type 3 Innate Lymphoid Cells and Classical Monocytes in a Patient with Hyper-IgE Syndrome.

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Chang, Yuna; Kang, Sung-Yoon; Kim, Jihyun; Kang, Hye-Ryun; Kim, Hye Young

2017-10-01

Hyper-IgE syndrome (HIES) is a very rare primary immune deficiency characterized by elevated serum IgE levels, recurrent bacterial infections, chronic dermatitis, and connective tissue abnormalities. Autosomal dominant (AD) HIES involves a mutation in signal transducer and activator of transcription 3 (STAT3) that leads to an impaired T H 17 response. STAT3 signaling is also involved in the function of RORγt + type 3 innate lymphoid cells (ILC3s) and RORγt + T H 17 cells. The aim of this study was to investigate the role of innate immune cells such as innate lymphoid cells (ILCs), granulocytes, and monocytes in a patient with HIES. Peripheral blood mononuclear cells (PBMCs) from a patient with HIES and three age-matched healthy controls were obtained for the analysis of the innate and adaptive immune cells. The frequencies of ILCs in PBMCs were lower in the patient with HIES than in the controls. Moreover, granulocyte-macrophage colony-stimulating factor (GM-CSF) and IL-17A produced by ILC3s in PBMCs were lower in the patient with HIES than the controls. Compared with the controls, classical monocytes (CD14 + CD16 low ), which have a high antimicrobial capability, were also lower in the patient with HIES, while non-classical monocytes (CD14 low CD16 + ) as well as intermediate monocytes (CD14 + CD16 intermediate ) were higher. Taken together, these results indicate that the impaired immune defense against pathogenic microbes in the patient with HIES might be partially explained by functional defects in ILC3s and inflammatory monocytes.

Systemic T Cells Immunosuppression of Glioma Stem Cell-Derived Exosomes Is Mediated by Monocytic Myeloid-Derived Suppressor Cells.

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Rossana Domenis

Full Text Available A major contributing factor to glioma development and progression is its ability to evade the immune system. Nano-meter sized vesicles, exosomes, secreted by glioma-stem cells (GSC can act as mediators of intercellular communication to promote tumor immune escape. Here, we investigated the immunomodulatory properties of GCS-derived exosomes on different peripheral immune cell populations. Healthy donor peripheral blood mononuclear cells (PBMCs stimulated with anti-CD3, anti-CD28 and IL-2, were treated with GSC-derived exosomes. Phenotypic characterization, cell proliferation, Th1/Th2 cytokine secretion and intracellular cytokine production were analysed by distinguishing among effector T cells, regulatory T cells and monocytes. In unfractionated PBMCs, GSC-derived exosomes inhibited T cell activation (CD25 and CD69 expression, proliferation and Th1 cytokine production, and did not affect cell viability or regulatory T-cell suppression ability. Furthermore, exosomes were able to enhance proliferation of purified CD4+ T cells. In PBMCs culture, glioma-derived exosomes directly promoted IL-10 and arginase-1 production and downregulation of HLA-DR by unstimulated CD14+ monocytic cells, that displayed an immunophenotype resembling that of monocytic myeloid-derived suppressor cells (Mo-MDSCs. Importantly, the removal of CD14+ monocytic cell fraction from PBMCs restored T-cell proliferation. The same results were observed with exosomes purified from plasma of glioblastoma patients. Our results indicate that glioma-derived exosomes suppress T-cell immune response by acting on monocyte maturation rather than on direct interaction with T cells. Selective targeting of Mo-MDSC to treat glioma should be considered with regard to how immune cells allow the acquirement of effector functions and therefore counteracting tumor progression.

Effect of selective phosphodiesterase inhibitors on the rat eosinophil chemotactic response in vitro

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Alves Alessandra C

1997-01-01

Full Text Available In the present study, we have performed a comparative analysis of the effect of selective inhibitors of phosphodiesterase (PDE type III, IV and V on eosinophil chemotaxis triggered by platelet activating factor (PAF and leukotriene B4 (LTB4 in vitro. The effect of the analogues N6-2'-O-dibutyryladenosine 3':5' cyclic monophosphate (Bt2 cyclic AMP and N2-2'-O- dibutyrylguanosine 3':5' cyclic monophosphate (Bt2 cyclic GMP has also been determined. The eosinophils were obtained from the peritoneal cavity of naive Wistar rats and purified in discontinuous Percoll gradients to 85-95% purity. We observed that pre-incubation of eosinophils with the PDE type IV inhibitor rolipram suppressed the chemotactic response triggered by PAF and LTB4, in association with an increase in the intracellular levels of cyclic AMP. In contrast, neither zaprinast (type V inhibitor nor type III inhibitors milrinone and SK&F 94836 affected the eosinophil migration. Only at the highest concentration tested did the analogue Bt2 cyclic AMP suppress the eosinophil chemotaxis, under conditions where Bt2 cyclic GMP was ineffective. We have concluded that inhibition of PDE IV, but not PDE III or V, was able to block the eosinophil chemotaxis in vitro, suggesting that the suppressive activity of selective PDE IV inhibitors on tissue eosinophil accumulation may, at least, be partially dependent on their ability to directly inhibit the eosinophil migration.

A role for inflammatory mediators in heterologous desensitization of CysLT1 receptor in human monocytes

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Capra, Valérie; Accomazzo, Maria Rosa; Gardoni, Fabrizio; Barbieri, Silvia; Rovati, G. Enrico

2010-01-01

Cysteinyl-leukotrienes (cysteinyl-LT) are rapidly generated at sites of inflammation and, in addition to their role in asthma, rhinitis, and other immune disorders, are increasingly regarded as significant inflammatory factors in cancer, gastrointestinal, cardiovascular diseases. We recently demonstrated that in monocyte/macrophage–like U937 cells, extracellular nucleotides heterologously desensitize CysLT1 receptor (CysLT1R)-induced Ca2+ transients. Given that monocytes express a number of other inflammatory and chemoattractant receptors, this study was aimed at characterizing transregulation between these different stimuli. We demonstrate that in U937 cells and in primary human monocytes, a series of inflammatory mediators activating Gi-coupled receptor (FPR1, BLT1) desensitize CysLT1R-induced Ca2+ response unidirectionally through activation of PKC. Conversely, PAF-R, exclusively coupled to Gq, cross-desensitizes CysLT1R without the apparent involvement of any kinase. Interestingly, Gs-coupled receptors (β2AR, H1/2R, EP2/4R) are also able to desensitize CysLT1R response through activation of PKA. Heterologous desensitization seems to affect mostly the Gi-mediated signaling of the CysLT1R. The hierarchy of desensitization among agonists may be important for leukocyte signal processing at the site of inflammation. Considering that monocytes/macrophages are likely to be the major source of cysteinyl-LT in many immunological and inflammatory processes, shedding light on how their receptors are regulated will certainly help to better understand the role of these cells in orchestrating this complex network of integrated signals. PMID:19965602

Identification of proangiogenic TIE2-expressing monocytes (TEMs) in human peripheral blood and cancer

OpenAIRE

Venneri, Mary Anna; De Palma, Michele; Ponzoni, Maurilio; Pucci, Ferdinando; Scielzo, Cristina; Zonari, Erika; Mazzieri, Roberta; Doglioni, Claudio; Naldini, Luigi

2007-01-01

Tumor-infiltrating myeloid cells, including tumor-associated macrophages (TAMs), have been implicated in tumor progression. We recently described a lineage of mouse monocytes characterized by expression of the Tie2 angiopoietin receptor and required for the vascularization and growth of several tumor models. Here, we report that TIE2 expression in human blood identifies a subset of monocytes distinct from classical inflammatory monocytes and comprised within the less abundant "resident" popul...

Improvement in the Function of rat Peripheral Blood Monocytes Following Oral Administration of Curcumin

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H Zirak Marangalu

2017-06-01

Conclusions: Collectively, it seems that curcumin is a natural source to intervene the monocytes functions especially in autoimmune diseases so that monocytes hyperactivity causes immunopathological conditions.

Regulatory NK cells mediated between immunosuppressive monocytes and dysfunctional T cells in chronic HBV infection.

Science.gov (United States)

Li, Haijun; Zhai, Naicui; Wang, Zhongfeng; Song, Hongxiao; Yang, Yang; Cui, An; Li, Tianyang; Wang, Guangyi; Niu, Junqi; Crispe, Ian Nicholas; Su, Lishan; Tu, Zhengkun

2017-09-12

HBV infection represents a major health problem worldwide, but the immunological mechanisms by which HBV causes chronic persistent infection remain only partly understood. Recently, cell subsets with suppressive features have been recognised among monocytes and natural killer (NK) cells. Here we examine the effects of HBV on monocytes and NK cells. Monocytes and NK cells derived from chronic HBV-infected patients and healthy controls were purified and characterised for phenotype, gene expression and cytokines secretion by flow cytometry, quantitative real-time (qRT)-PCR, ELISA and western blotting. Culture and coculture of monocytes and NK cells were used to determine NK cell activation, using intracellular cytokines staining. In chronic HBV infection, monocytes express higher levels of PD-L1, HLA-E, interleukin (IL)-10 and TGF-β, and NK cells express higher levels of PD-1, CD94 and IL-10, compared with healthy individuals. HBV employs hepatitis B surface antigen (HBsAg) to induce suppressive monocytes with HLA-E, PD-L1, IL-10 and TGF-β expression via the MyD88/NFκB signalling pathway. HBV-treated monocytes induce NK cells to produce IL-10, via PD-L1 and HLA-E signals. Such NK cells inhibit autologous T cell activation. Our findings reveal an immunosuppressive cascade, in which HBV generates suppressive monocytes, which initiate regulatory NK cells differentiation resulting in T cell inhibition. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

A monocyte chemotaxis inhibiting factor in serum of HIV infected men shares epitopes with the HIV transmembrane protein gp41

NARCIS (Netherlands)

Tas, M.; Drexhage, H. A.; Goudsmit, J.

1988-01-01

This report describes that gp41, the transmembranous envelope protein of HIV, is able to inhibit monocyte chemotaxis (measured as FMLP-induced polarization). To study the presence of such immunosuppressive HIV env proteins in the circulation of HIV-infected men, fractions were prepared from serum

Identification of proangiogenic TIE2-expressing monocytes (TEMs) in human peripheral blood and cancer.

Science.gov (United States)

Venneri, Mary Anna; De Palma, Michele; Ponzoni, Maurilio; Pucci, Ferdinando; Scielzo, Cristina; Zonari, Erika; Mazzieri, Roberta; Doglioni, Claudio; Naldini, Luigi

2007-06-15

Tumor-infiltrating myeloid cells, including tumor-associated macrophages (TAMs), have been implicated in tumor progression. We recently described a lineage of mouse monocytes characterized by expression of the Tie2 angiopoietin receptor and required for the vascularization and growth of several tumor models. Here, we report that TIE2 expression in human blood identifies a subset of monocytes distinct from classical inflammatory monocytes and comprised within the less abundant "resident" population. These TIE2-expressing monocytes (TEMs) accounted for 2% to 7% of blood mononuclear cells in healthy donors and were distinct from rare circulating endothelial cells and progenitors. In human cancer patients, TEMs were observed in the blood and, intriguingly, within the tumors, where they represented the main monocyte population distinct from TAMs. Conversely, TEMs were hardly detected in nonneoplastic tissues. In vitro, TEMs migrated toward angiopoietin-2, a TIE2 ligand released by activated endothelial cells and angiogenic vessels, suggesting a homing mechanism for TEMs to tumors. Purified human TEMs, but not TEM-depleted monocytes, markedly promoted angiogenesis in xenotransplanted human tumors, suggesting a potentially critical role of TEMs in human cancer progression. Human TEMs may provide a novel, biologically relevant marker of angiogenesis and represent a previously unrecognized target of cancer therapy.

Niacin results in reduced monocyte adhesion in patients with type 2 diabetes mellitus.

Science.gov (United States)

Tavintharan, S; Woon, K; Pek, L T; Jauhar, N; Dong, X; Lim, S C; Sum, C F

2011-03-01

Patients with type 2 diabetes have increased expression of cell adhesion molecules (CAMs). CAMs and monocyte adhesion mediate essential processes in atherogenesis. It remains unclear if monocytes from patients on niacin have reduced adhesion function. We studied the variation of monocyte adhesion in patients with type 2 diabetes and low HDL-cholesterol, taking either extended release niacin (Niaspan®, Abbott Laboratories) or controls not on niacin. Biochemical parameters including adiponectin, CAMs and fresh monocytes from whole blood for adhesion assays, were studied at baseline and 12-weeks. Niacin 1500 mg daily raised HDL-cholesterol from 0.8 mmol/l (95% CI: 0.7-0.9) to 0.9 mmol/l (95% CI: 0.8-1.1), p=0.10, and significantly reduced PECAM-1 by 24.9% (95% CI: 10.9-39.0; p<0.05), increased adiponectin by 30.5% (95% CI: 14.1-47.0; p<0.05), with monocyte adhesion reduced by 9.2% (95%CI: 0.7-17.7; p<0.05) in endothelial cells treated in basal conditions, and 7.8% (95% CI: 3.1-12.5; p<0.05) after TNF-α stimulation. Monocytes isolated from patients on niacin had reduced adhesion to endothelial cells. Our findings suggest niacin has broad range of effects apart from lipid-modification, and these could be important in cardiovascular risk reduction. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Epigenetic Regulation of Monocyte and Macrophage Function

NARCIS (Netherlands)

Hoeksema, Marten A.; de Winther, Menno P. J.

2016-01-01

Monocytes and macrophages are key players in tissue homeostasis and immune responses. Epigenetic processes tightly regulate cellular functioning in health and disease. Recent Advances: Recent technical developments have allowed detailed characterizations of the transcriptional circuitry underlying

SIMULTANEOUS EXPRESSION AND REGULATION OF G-CSF AND IL-6 MESSENGER-RNA IN ADHERENT HUMAN MONOCYTES AND FIBROBLASTS

NARCIS (Netherlands)

VELLENGA, E; VANDERVINNE, B; DEWOLF, JTM; HALIE, MR

The regulation of granulocyte-colony stimulating factor (G-CSF) and interleukin-6 (IL-6) mRNA was studied in human adherent monocytes in response to the protein kinase C activator, oleolyl-acetylglycerol (OAG), the calcium-ionophore A23187 and the cyclic AMP elevating agents, dibutyryl c-AMP

In Vitro experimental model of trained innate immunity in human primary monocytes

DEFF Research Database (Denmark)

Bekkering, S.; Blok, B. A.; Joosten, Leo A B

2016-01-01

experimental protocol of monocyte training using three of the most commonly used training stimuli from the literature: β-glucan, the bacillus Calmette-Guérin (BCG) vaccine, and oxidized low-density lipoprotein (ox-LDL). We investigated and optimized a protocol of monocyte trained immunity induced by an initial....... All Rights Reserved....

The Effect of Aggregatibacter actinomycetemcomitans Leukotoxin on Cell-to-Cell Communication in Human Monocytes

OpenAIRE

Hussein, Bejyan; Tamali, Ali

2014-01-01

Periodontitis is a complex and multifactorial dental disease and without proper treatment it eventually leads to the loss of teeth. Individuals with a higher number of Aggregatibacter actinomycetemcomitans in their micro-flora have a greater risk of developing periodontitis and the bacterium is associated with local aggressive periodontitis that affects younger populations. Aa produces a toxic virulent factor named Leukotoxin-A that can activate monocytes by a cellular chain reaction resultin...

Electroacupuncture decreases the progression of ovarian hyperstimulation syndrome in a rat model.

Science.gov (United States)

Chen, Li; Sun, Hai-Xiang; Xia, You-Bing; Sui, Liu-Cai; Zhou, Ji; Huang, Xuan; Zhou, Jing-Wei; Shao, Yi-Dan; Shen, Tao; Sun, Qin; Liang, Yuan-Jiao; Yao, Bing

2016-05-01

This study aimed to elucidate the effect of electroacupuncture treatment on preventing early ovarian hyperstimulation syndrome (OHSS) and the potential mechanisms involved using an induced rat model. The ovarian response was examined by measuring ovary weight, vascular permeability, levels of inflammation (interleukin-6), tumour necrosis factor alpha, chemokine ligand 2 (also known as monocyte chemoactic protein 1), vascular endothelial growth factor and hormone concentrations (oestradiol, progesterone, testosterone and prolactin). Sprague-Dawley female rats underwent ovarian stimulation to induce OHSS. Hyperstimulated rats received consecutive electroacupuncture treatment from 3 days before the beginning of pregnant mare serum gonadotrophin treatment or the time point of pregnant mare serum gonadotrophin treatment respectively, and last until 3 days after HCG administration. Electroacupuncture treatment reduced ovary weight and vascular permeability in hyperstimulated rats. Electroacupuncture treatment also reduced the levels of serum steroid hormones (progesterone and testosterone), inflammatory cytokines (interleukin-6, tumour necrosis factor alpha and monocyte chemotactic protein 1 and vascular endothelial growth factor in hyperstimulated rats. The results indicate that electroacupuncture can modulate endocrine hormone secretion and affect the secretion of inflammatory cytokines and vascular endothelial growth factor, and thus prevent the progress of OHSS. Electroacupuncture may provide a simple and effective method for the prevention and treatment of OHSS. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Aged mice have increased inflammatory monocyte concentration ...

Indian Academy of Sciences (India)

monocytes from old as compared with those from young mice. The increased classic .... several instances where the isotype control antibodies stained in a similar position but at a ..... responses in young and older adults. J. Infect. Dis. 195.

Thioredoxin 80-Activated-Monocytes (TAMs) Inhibit the Replication of Intracellular Pathogens

DEFF Research Database (Denmark)

Cortes-Bratti, Ximena; Brasseres, Eugenie; Herrera-Rodriquez, Fabiola

2011-01-01

Background: Thioredoxin 80 (Trx80) is an 80 amino acid natural cleavage product of Trx, produced primarily by monocytes. Trx80 induces differentiation of human monocytes into a novel cell type, named Trx80-activated-monocytes (TAMs). Principal Findings: In this investigation we present evidence...... for a role of TAMs in the control of intracellular bacterial infections. As model pathogens we have chosen Listeria monocytogenes and Brucella abortus which replicate in the cytosol and the endoplasmic reticulum respectively. Our data indicate that TAMs efficiently inhibit intracellular growth of both L...... in TAMs compared to that observed in control cells 24 h post-infection, indicating that TAMs kill bacteria by preventing their escape from the endosomal compartments, which progress into a highly degradative phagolysosome. Significance: Our results show that Trx80 potentiates the bactericidal activities...

Synthesis of pro-inflammatory cytokines and adhesion molecules expression by the irradiated human monocyte/macrophage

International Nuclear Information System (INIS)

Pons, I.

1997-09-01

As lesions induced by ionizing radiations are essentially noticed in organs the functional and structural organisation of which depend on the highly proliferative stem cell pool, the author reports an in-vivo investigation of the effect of a gamma irradiation on the expression and secretion of pro-inflammatory cytokines par human monocytes/macrophages. In order to study the role of the cell environment in the radiation-induced inflammation, the author studied whether a co-stimulation of monocytes/macrophages by gamma irradiation, or the exposure of co-cultures of monocytes/macrophages and lymphocytes, could modulate the regulation of inflammatory cytokines. The author also studied the modulation of the expression of adhesion molecules mainly expressed by the monocyte/macrophage, and the membrane density of the CD14 receptor after irradiation of monocytes/macrophages during 24 hours, and of totally differentiated macrophages after seven days of culture

Stress, Inflammation and Pain: A Potential Role for Monocytes in Fibromyalgia-related Symptom Severity.

Science.gov (United States)

Taylor, Ann Gill; Fischer-White, Tamara G; Anderson, Joel G; Adelstein, Katharine E; Murugesan, Maheswari; Lewis, Janet E; Scott, Michael M; Gaykema, Ronald P A; Goehler, Lisa E

2016-12-01

The possibility that immunological changes might contribute to symptom severity in fibromyalgia (FM) prompted this proof-of-concept study to determine whether differences in monocyte subpopulations might be present in persons with FM compared with healthy controls. Relationships were assessed by comparing specific symptoms in those with FM (n = 20) and patterns of monocyte subpopulations with healthy age-matched and gender-matched controls (n = 20). Within the same time frame, all participants provided a blood sample and completed measures related to pain, fatigue, sleep disturbances, perceived stress, positive and negative affect and depressed mood (and the Fibromyalgia Impact Questionnaire for those with FM). Monocyte subpopulations were assessed using flow cytometry. No differences were observed in total percentages of circulating monocytes between the groups; however, pain was inversely correlated with percentages of circulating classical (r = -0.568, p = 0.011) and intermediate (r = -0.511, p = 0.025) monocytes in the FM group. Stress and pain were highly correlated (r = 0.608, p = 0.004) in the FM group. The emerging pattern of changes in the percentages of circulating monocyte subpopulations concomitant with higher ratings of perceived pain and the correlation between stress and pain found in the FM group warrant further investigation. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

The Preoperative Peripheral Blood Monocyte Count Is Associated with Liver Metastasis and Overall Survival in Colorectal Cancer Patients.

Directory of Open Access Journals (Sweden)

Shidong Hu

Full Text Available Colorectal cancer (CRC is the third most common malignancy in males and the second most common in females worldwide. Distant metastases have a strong negative impact on the prognosis of CRC patients. The most common site of CRC metastases is the liver. Both disease progression and metastasis have been related to the patient's peripheral blood monocyte count. We therefore performed a case-control study to assess the relationship between the preoperative peripheral blood monocyte count and colorectal liver metastases (CRLM.Clinical data from 117 patients with colon cancer and 93 with rectal cancer who were admitted to the Chinese People's Liberation Army General Hospital (Beijing, China between December 2003 and May 2015 were analysed retrospectively, with the permission of both the patients and the hospital.Preoperative peripheral blood monocyte counts, the T and N classifications of the primary tumour and its primary site differed significantly between the two groups (P 0.505 × 109 cells/L, high T classification and liver metastasis were independent risk factors for 5-year OS (RR: 2.737, 95% CI: 1.573~ 4.764, P <0.001; RR: 2.687, 95%CI: 1.498~4.820, P = 0.001; RR: 4.928, 95%CI: 2.871~8.457, P < 0.001.The demonstrated association between preoperative peripheral blood monocyte count and liver metastasis in patients with CRC recommends the former as a useful predictor of postoperative prognosis in CRC patients.

The Preoperative Peripheral Blood Monocyte Count Is Associated with Liver Metastasis and Overall Survival in Colorectal Cancer Patients.

Science.gov (United States)

Hu, Shidong; Zou, Zhenyu; Li, Hao; Zou, Guijun; Li, Zhao; Xu, Jian; Wang, Lingde; Du, Xiaohui

2016-01-01

Colorectal cancer (CRC) is the third most common malignancy in males and the second most common in females worldwide. Distant metastases have a strong negative impact on the prognosis of CRC patients. The most common site of CRC metastases is the liver. Both disease progression and metastasis have been related to the patient's peripheral blood monocyte count. We therefore performed a case-control study to assess the relationship between the preoperative peripheral blood monocyte count and colorectal liver metastases (CRLM). Clinical data from 117 patients with colon cancer and 93 with rectal cancer who were admitted to the Chinese People's Liberation Army General Hospital (Beijing, China) between December 2003 and May 2015 were analysed retrospectively, with the permission of both the patients and the hospital. Preoperative peripheral blood monocyte counts, the T and N classifications of the primary tumour and its primary site differed significantly between the two groups (P colon cancer (OR: 0.078, 95%CI: 0.020~0.309, P 0.505 × 109 cells/L, high T classification and liver metastasis were independent risk factors for 5-year OS (RR: 2.737, 95% CI: 1.573~ 4.764, P <0.001; RR: 2.687, 95%CI: 1.498~4.820, P = 0.001; RR: 4.928, 95%CI: 2.871~8.457, P < 0.001). The demonstrated association between preoperative peripheral blood monocyte count and liver metastasis in patients with CRC recommends the former as a useful predictor of postoperative prognosis in CRC patients.

Clinical characteristics of inflammation-associated depression: Monocyte gene expression is age-related in major depressive disorder.

Science.gov (United States)

Grosse, Laura; Carvalho, Livia A; Wijkhuijs, Annemarie J M; Bellingrath, Silja; Ruland, Tillmann; Ambrée, Oliver; Alferink, Judith; Ehring, Thomas; Drexhage, Hemmo A; Arolt, Volker

2015-02-01

Increased inflammatory activation might only be present in a subgroup of depressed individuals in which immune processes are especially relevant to disease development. We aimed to analyze demographic, depression, and trauma characteristics of major depressive disorder (MDD) patients with regard to inflammatory monocyte gene expression. Fifty-six naturalistically treated MDD patients (32 ± 12 years) and 57 healthy controls (HC; 31 ± 11 years) were analyzed by the Inventory of Depressive Symptomatology (IDS) and by the Childhood Trauma Questionnaire (CTQ). We determined the expression of 38 inflammatory and immune activation genes including the glucocorticoid receptor (GR)α and GRβ genes in purified CD14(+) monocytes using quantitative-polymerase chain reaction (RT-qPCR). Monocyte gene expression was age-dependent, particularly in MDD patients. Increased monocyte gene expression and decreased GRα/β ratio were only present in MDD patients aged ⩾ 28 years. Post hoc analyses of monocyte immune activation in patients depression (recurrent type, onset depression, onset ⩾15 years) - additionally characterized by the absence of panic symptoms - that exhibited a strongly reduced inflammatory monocyte activation compared to HC. In conclusion, monocyte immune activation was not uniformly raised in MDD patients but was increased only in patients of 28 years and older. Copyright © 2014 Elsevier Inc. All rights reserved.

Monocytes infiltrate the pancreas via the MCP-1/CCR2 pathway and differentiate into stellate cells.

Directory of Open Access Journals (Sweden)

Kazuko Ino

Full Text Available Recent studies have shown that monocytes possess pluripotent plasticity. We previously reported that monocytes could differentiate into hepatic stellate cells. Although stellate cells are also present in the pancreas, their origin remains unclear. An accumulation of enhanced green fluorescent protein (EGFP(+CD45(- cells was observed in the pancreases and livers of chimeric mice, which were transplanted with a single hematopoietic stem cell isolated from EGFP-transgenic mice and treated with carbon tetrachloride (CCl4. Because the vast majority of EGFP(+CD45(- cells in the pancreas expressed stellate cell-associated antigens such as vimentin, desmin, glial fibrillary acidic protein, procollagen-I, and α-smooth muscle actin, they were characterized as pancreatic stellate cells (PaSCs. EGFP(+ PaSCs were also observed in CCl4-treated mice adoptively transferred with monocytes but not with other cell lineages isolated from EGFP-transgenic mice. The expression of monocyte chemoattractant protein-1 (MCP-1 and angiotensin II (Ang II increased in the pancreas of CCl4-treated mice and their respective receptors, C-C chemokine receptor 2 (CCR2 and Ang II type 1 receptor (AT1R, were expressed on Ly6C(high monocytes isolated from EGFP-transgenic mice. We examined the effect of an AT1R antagonist, irbesartan, which is also a CCR2 antagonist, on the migration of monocytes into the pancreas. Monocytes migrated toward MCP-1 but not Ang II in vitro. Irbesartan inhibited not only their in vitro chemotaxis but also in vivo migration of adoptively transferred monocytes from peripheral blood into the pancreas. Irbesartan treatment significantly reduced the numbers of EGFP(+F4/80(+CCR2(+ monocytic cells and EGFP(+ PaSCs in the pancreas of CCl4-treated chimeric mice receiving EGFP(+ bone marrow cells. A specific CCR2 antagonist RS504393 inhibited the occurrence of EGFP(+ PaSCs in injured mice. We propose that CCR2(+ monocytes migrate into the pancreas possibly via the

Whole blood flow cytometric analysis of Ureaplasma-stimulated monocytes from pregnant women.

Science.gov (United States)

Friedland, Yael D; Lee-Pullen, Tracey F; Nathan, Elizabeth; Watts, Rory; Keelan, Jeffrey A; Payne, Matthew S; Ireland, Demelza J

2015-06-01

We hypothesised that circulating monocytes of women with vaginal colonisation with Ureaplasma spp., genital microorganisms known to cause inflammation-driven preterm birth, would elicit a tolerised cytokine response to subsequent in vitro Ureaplasma parvum serovar 3 (UpSV3) stimulation. Using multi-parameter flow cytometry, we found no differences with regard to maternal colonisation status in the frequency of TNF-α-, IL-6-, IL-8- and IL-1β-expressing monocytes in response to subsequent UpSV3 stimulation (P > 0.10 for all cytokines). We conclude that vaginal Ureaplasma spp. colonisation does not specifically tolerise monocytes of pregnant women towards decreased responses to subsequent stimulation. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Integrin αMβ2 is differently expressed by subsets of human osteoclast precursors and mediates adhesion of classical monocytes to bone

Energy Technology Data Exchange (ETDEWEB)

Sprangers, Sara, E-mail: s.l.sprangers@acta.nl [Department of Oral Cell Biology and Functional Anatomy, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and VU University Amsterdam, MOVE Research Institute Amsterdam, Gustav Mahlerlaan 3004, 1081 LA Amsterdam The Netherlands (Netherlands); Schoenmaker, Ton, E-mail: t.schoenmaker@acta.nl [Department of Oral Cell Biology and Functional Anatomy, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and VU University Amsterdam, MOVE Research Institute Amsterdam, Gustav Mahlerlaan 3004, 1081 LA Amsterdam The Netherlands (Netherlands); Department of Periodontology, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and VU University Amsterdam, MOVE Research Institute Amsterdam, Gustav Mahlerlaan 3004, 1081 LA Amsterdam The Netherlands (Netherlands); Cao, Yixuan, E-mail: y.cao@acta.nl [Department of Oral Cell Biology and Functional Anatomy, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and VU University Amsterdam, MOVE Research Institute Amsterdam, Gustav Mahlerlaan 3004, 1081 LA Amsterdam The Netherlands (Netherlands); Everts, Vincent, E-mail: v.everts@acta.nl [Department of Oral Cell Biology and Functional Anatomy, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and VU University Amsterdam, MOVE Research Institute Amsterdam, Gustav Mahlerlaan 3004, 1081 LA Amsterdam The Netherlands (Netherlands); Vries, Teun J. de, E-mail: teun.devries@acta.nl [Department of Oral Cell Biology and Functional Anatomy, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and VU University Amsterdam, MOVE Research Institute Amsterdam, Gustav Mahlerlaan 3004, 1081 LA Amsterdam The Netherlands (Netherlands); Department of Periodontology, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and VU University Amsterdam, MOVE Research Institute Amsterdam, Gustav Mahlerlaan 3004, 1081 LA Amsterdam The Netherlands (Netherlands)

2017-01-01

Bone-degrading osteoclasts are formed through fusion of their monocytic precursors. In the population of human peripheral blood monocytes, three distinct subsets have been identified: classical, intermediate and non-classical monocytes. We have previously shown that when the monocyte subsets are cultured on bone, significantly more osteoclasts are formed from classical monocytes than from intermediate or non-classical monocytes. Considering that this difference does not exist when monocyte subsets are cultured on plastic, we hypothesized that classical monocytes adhere better to the bone surface compared to intermediate and non-classical monocytes. To investigate this, the different monocyte subsets were isolated from human peripheral blood and cultured on slices of human bone in the presence of the cytokine M-CSF. We found that classical monocytes adhere better to bone due to a higher expression of the integrin αMβ2 and that their ability to attach to bone is significantly decreased when the integrin is blocked. This suggests that integrin αMβ2 mediates attachment of osteoclast precursors to bone and thereby enables the formation of osteoclasts.

Gamma interferon augments Fc gamma receptor-mediated dengue virus infection of human monocytic cells.

OpenAIRE

Kontny, U; Kurane, I; Ennis, F A

1988-01-01

It has been reported that anti-dengue antibodies at subneutralizing concentrations augment dengue virus infection of monocytic cells. This is due to the increased uptake of dengue virus in the form of virus-antibody complexes by cells via Fc gamma receptors. We analyzed the effects of recombinant human gamma interferon (rIFN-gamma) on dengue virus infection of human monocytic cells. U937 cells, a human monocytic cell line, were infected with dengue virus in the form of virus-antibody complexe...

Fatty Acid Oxidation Compensates for Lipopolysaccharide-Induced Warburg Effect in Glucose-Deprived Monocytes

Directory of Open Access Journals (Sweden)

Nora Raulien

2017-05-01

Full Text Available Monocytes enter sites of microbial or sterile inflammation as the first line of defense of the immune system and initiate pro-inflammatory effector mechanisms. We show that activation with bacterial lipopolysaccharide (LPS induces them to undergo a metabolic shift toward aerobic glycolysis, similar to the Warburg effect observed in cancer cells. At sites of inflammation, however, glucose concentrations are often drastically decreased, which prompted us to study monocyte function under conditions of glucose deprivation and abrogated Warburg effect. Experiments using the Seahorse Extracellular Flux Analyzer revealed that limited glucose supply shifts monocyte metabolism toward oxidative phosphorylation, fueled largely by fatty acid oxidation at the expense of lipid droplets. While this metabolic state appears to provide sufficient energy to sustain functional properties like cytokine secretion, migration, and phagocytosis, it cannot prevent a rise in the AMP/ATP ratio and a decreased respiratory burst. The molecular trigger mediating the metabolic shift and the functional consequences is activation of AMP-activated protein kinase (AMPK. Taken together, our results indicate that monocytes are sufficiently metabolically flexible to perform pro-inflammatory functions at sites of inflammation despite glucose deprivation and inhibition of the LPS-induced Warburg effect. AMPK seems to play a pivotal role in orchestrating these processes during glucose deprivation in monocytes.

Can TIE-2 expressing monocytes represent a novel marker for hepatocellular carcinoma?

Science.gov (United States)

Dapas, Barbara; Grassi, Mario; Grassi, Gabriele

2014-08-01

Hepatocellular carcinoma (HCC), the predominant form of primary liver cancer, is a global health problem representing the sixth most common cancer and the third cause of cancer related death worldwide. The number of deaths per year in HCC is comparable to the incidence number, underlying the aggressive behavior of HCC and the modest efficacy of available curative treatments. Effective HCC treatment is problematic also due to the lack of early and specific diagnostic markers. In this regard, particular interest has been put on the tyrosine kinase with Ig and endothelial growth factor (EGF) homology domains 2 (TIE2), a receptor of angiopoietins, predominantly present on endothelial cells but also observed on monocytes [TIE-2-expressing monocytes (TEMs)]. Recently, a work by Matsubara et al. showed that the amount of circulating TEMs is higher in hepatitis virus C (HCV)/HCC patients compared to HCV patients or healthy subjects. Additionally the authors showed that TEMs have a diagnostic potential for HCC. Whereas the molecular mechanisms responsible for this observation remain elusive and further studies are necessary to confirm this finding, the work of Matsubara et al. may contribute to the identification of a novel HCC prognostic and diagnostic marker.

CD16+ Monocytes and Skewed Macrophage Polarization toward M2 Type Hallmark Heart Transplant Acute Cellular Rejection.

Science.gov (United States)

van den Bosch, Thierry P P; Caliskan, Kadir; Kraaij, Marina D; Constantinescu, Alina A; Manintveld, Olivier C; Leenen, Pieter J M; von der Thüsen, Jan H; Clahsen-van Groningen, Marian C; Baan, Carla C; Rowshani, Ajda T

2017-01-01

During acute heart transplant rejection, infiltration of lymphocytes and monocytes is followed by endothelial injury and eventually myocardial fibrosis. To date, no information is available on monocyte-macrophage-related cellular shifts and their polarization status during rejection. Here, we aimed to define and correlate monocyte-macrophage endomyocardial tissue profiles obtained at rejection and time points prior to rejection, with corresponding serial blood samples in 25 heart transplant recipients experiencing acute cellular rejection. Additionally, 33 healthy individuals served as control. Using histology, immunohistochemistry, confocal laser scan microscopy, and digital imaging expression of CD14, CD16, CD56, CD68, CD80, and CD163 were explored to define monocyte and macrophage tissue profiles during rejection. Fibrosis was investigated using Sirius Red stainings of rejection, non-rejection, and 1-year biopsies. Expression of co-stimulatory and migration-related molecules on circulating monocytes, and production potential for pro- and anti-inflammatory cytokines were studied using flow cytometry. At tissue level, striking CD16+ monocyte infiltration was observed during rejection ( p  rejection compared to barely present CD68+CD80+ M1 macrophages. Rejection was associated with severe fibrosis in 1-year biopsies ( p  rejection status, decreased frequencies of circulating CD16+ monocytes were found in patients compared to healthy individuals. Rejection was reflected by significantly increased CD54 and HLA-DR expression on CD16+ monocytes with retained cytokine production potential. CD16+ monocytes and M2 macrophages hallmark the correlates of heart transplant acute cellular rejection on tissue level and seem to be associated with fibrosis in the long term.

Binding of α2-macroglobulin-thrombin complexes and methylamine-treated α2-macroglobulin to human blood monocytes

International Nuclear Information System (INIS)

Straight, D.L.; Jakoi, L.; McKee, P.A.; Snyderman, R.

1988-01-01

The binding of α 2 -macroglobulin (α 2 M) to human peripheral blood monocytes was investigated. Monocytes, the precursors of tissue macrophages, were isolated from fresh blood by centrifugal elutriation or density gradient centrifugation. Binding studies were performed using 125 I-labeled α 2 M. Cells and bound ligand were separated from free ligand by rapid vacuum filtration. Nonlinear least-squares analysis of data obtained in direct binding studies at 0 0 C showed that monocytes bound the α 2 M-thrombin complex with a K/sub d/ 3.0 +- .09 nM and the monocyte had 1545 +- 153 sitescell. Thrombin alone did not compete for the site. Binding was divalent cation dependent. Direct binding studies also demonstrated that monocytes bound methylamine-treated α 2 M in a manner similar to α 2 M-thrombin. Competitive binding studies showed that α 2 M-thrombin and methylamine-treated α 2 M bound to the same sites on the monocyte. In contrast, native α 2 M did not compete with α 2 M-thrombin for the site. Studies done at 37 0 C suggested that after binding, the monocyte internalized and degraded α 2 M-thrombin and excreted the degradation products. Receptor turnover and degradation of α 2 M-thrombin complexes were blocked in monocytes treated with chloroquine, an inhibitor of lysosomal function. The results indicate that human monocytes have a divalent cation dependent, high-affinity binding site for α 2 M-thrombin and methylamine-treated α 2 M which may function to clear α 2 M-proteinase complexes from the circulation

Glycoengineering of therapeutic antibodies enhances monocyte/macrophage-mediated phagocytosis and cytotoxicity.

Science.gov (United States)

Herter, Sylvia; Birk, Martina C; Klein, Christian; Gerdes, Christian; Umana, Pablo; Bacac, Marina

2014-03-01

Therapeutic Abs possess several clinically relevant mechanisms of action including perturbation of tumor cell signaling, activation of complement-dependent cytotoxicity, Ab-dependent cellular cytotoxicity (ADCC), Ab-dependent cellular phagocytosis (ADCP), and induction of adaptive immunity. In view of the important role of phagocytic lineage cells in the mechanism of action of therapeutic Abs, we analyzed FcγR receptor-dependent effector functions of monocytes and macrophages triggered by glycoengineered (GE) Abs (having enhanced FcγRIIIa [CD16a] binding affinity) versus their wild-type (WT) counterparts under different experimental conditions. We first defined the precise FcγR repertoire on classical and nonclassical intermediate monocytes--M1 and M2c macrophage populations. We further show that WT and GE Abs display comparable binding and induce similar effector functions (ADCC and ADCP) in the absence of nonspecific, endogenous IgGs. However, in the presence of these IgGs (i.e., in a situation that more closely mimics physiologic conditions), GE Abs display significantly superior binding and promote stronger monocyte and macrophage activity. These data show that in addition to enhancing CD16a-dependent NK cell cytotoxicity, glycoengineering also enhances monocyte and macrophage phagocytic and cytotoxic activities through enhanced binding to CD16a under conditions that more closely resemble the physiologic setting.

Efficient elutriation of monocytes within a closed system (Elutra) for clinical-scale generation of dendritic cells.

Science.gov (United States)

Berger, Thomas G; Strasser, Erwin; Smith, Richard; Carste, Curt; Schuler-Thurner, Beatrice; Kaempgen, Eckhart; Schuler, Gerold

2005-03-01

Dendritic cells (DC) are promising tools for the immunotherapy of cancer. The induction of tumor-specific T cells and clinical regressions have already been observed in early phase I/II vaccination trials. As DC vaccination is now facing trials with larger patient collectives it becomes increasingly important to obtain large numbers of cells suitable for therapeutic applications under labor- and cost-effective conditions. We describe here a procedure that uses a novel cell separator (Elutra, Gambro BCT) to enrich monocytes from an entire apheresis product within one hour. Cells are separated on the basis of size and to a lesser extent density, by elutriation in a 40-ml conical chamber. The total monocyte recovery following elutriation (n = 6) was 98.53% (+/-8.07%), the recovery in the monocyte-rich fraction 75.45% (+/-11.31%), and the mean purity 82.95% (+/-6.01%). These monocytes can be cultured either in conventional culture dishes or in closed cell culture bags and differentiated, by using GM-CSF+IL-4 followed by a maturation cocktail composed of IL-1beta+IL-6+TNF-alpha+PGE2, into fully mature DC. The Elutra separator allows for fast and easy enrichment of monocytes within a closed system. Subsequently, elutriated monocytes can be successfully cultured into phenotypically and functionally mature DC for immunotherapeutic approaches. The method neither requires a density gradient step to enrich PBMC from leucapheresis products nor does it apply (xenogeneic) antibodies to target monocytes. Isolation of monocytes with Elutra may greatly facilitate future DC-based vaccination approaches.

Prevention of UV irradiation induced suppression of monocyte functions by retinoids and carotenoids in vitro

International Nuclear Information System (INIS)

Schoen, D.J.; Watson, R.R.

1988-01-01

The effects of stimulation of human peripheral blood monocytes in vitro with retinoids and carotenoids, and subsequent exposure to ultraviolet light of the B wavelength were measured. The compounds were applied to the monocytes in culture for 24 h, and the washed cells were then exposed to UVB light up to 220 J/m 2 . The compounds tested protected the monocyte from UVB induced damage to phagocytic activity. This protection may be due to the antioxidant or UVB energy-quenching properties of these compounds. Monocyte cytotoxicity against a melanoma cell line was stimulated by exposure to the retinoids or carotenoids, but a protective effect in vitro against UVB damage was not seen for this cell function. (author)

Phenotypic, functional, and quantitative characterization of canine peripheral blood monocyte-derived macrophages

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R Bueno

2005-08-01

Full Text Available The yield as well as phenotypic and functional parameters of canine peripheral blood monocyte-derived macrophages were analyzed. The cells that remained adherent to Teflon after 10 days of culture had high phagocytic activity when inoculated with Leishmania chagasi. Flow cytometric analysis demonstrated that more than 80% of cultured cells were positive for the monocyte/macrophage marker CD14.

Expression profiling feline peripheral blood monocytes identifies a transcriptional signature associated with type two diabetes mellitus.

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O'Leary, Caroline A; Sedhom, Mamdouh; Reeve-Johnson, Mia; Mallyon, John; Irvine, Katharine M

2017-04-01

Diabetes mellitus is a common disease of cats and is similar to type 2 diabetes (T2D) in humans, especially with respect to the role of obesity-induced insulin resistance, glucose toxicity, decreased number of pancreatic β-cells and pancreatic amyloid deposition. Cats have thus been proposed as a valuable translational model of T2D. In humans, inflammation associated with adipose tissue is believed to be central to T2D development, and peripheral blood monocytes (PBM) are important in the inflammatory cascade which leads to insulin resistance and β-cell failure. PBM may thus provide a useful window to study the pathogenesis of diabetes mellitus in cats, however feline monocytes are poorly characterised. In this study, we used the Affymetrix Feline 1.0ST array to profile peripheral blood monocytes from 3 domestic cats with T2D and 3 cats with normal glucose tolerance. Feline monocytes were enriched for genes expressed in human monocytes, and, despite heterogeneous gene expression, we identified a T2D-associated expression signature associated with cell cycle perturbations, DNA repair and the unfolded protein response, oxidative phosphorylation and inflammatory responses. Our data provide novel insights into the feline monocyte transcriptome, and support the hypothesis that inflammatory monocytes contribute to T2D pathogenesis in cats as well as in humans. Copyright © 2017 Elsevier B.V. All rights reserved.

Studies on the mechanism of endogenous pyrogen production. III. Human blood monocytes.

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Bodel, P

1974-10-01

The characteristics of pyrogen production and release by human blood monocytes were investigated. A dose-response assay of monocyte pyrogen in rabbits indicated a linear relationship of temperature elevation to dose of pyrogen at lower doses. Monocytes did not contain pyrogen when first obtained, nor did they release it spontaneously even after 5 days of incubation in vitro. Pyrogen production was apparent 4 h after stimulation by endotoxin or phagocytosis, and continued for 24 h or more. Puromycin, an inhibitor of protein synthesis, prevented both initiation and continuation of pyrogen production and release. Pyrogen-containing supernates retained most pyrogenic activity during overnight incubation even in the presence of activated cells. Lymphocytes appeared to play no role in either initiation or continuation of pyrogen production in these studies.

Dopamine Increases CD14+CD16+ Monocyte Migration and Adhesion in the Context of Substance Abuse and HIV Neuropathogenesis

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Coley, Jacqueline S.; Calderon, Tina M.; Gaskill, Peter J.; Eugenin, Eliseo A.; Berman, Joan W.

2015-01-01

Drug abuse is a major comorbidity of HIV infection and cognitive disorders are often more severe in the drug abusing HIV infected population. CD14+CD16+ monocytes, a mature subpopulation of peripheral blood monocytes, are key mediators of HIV neuropathogenesis. Infected CD14+CD16+ monocyte transmigration across the blood brain barrier mediates HIV entry into the brain and establishes a viral reservoir within the CNS. Despite successful antiretroviral therapy, continued influx of CD14+CD16+ monocytes, both infected and uninfected, contributes to chronic neuroinflammation and the development of HIV associated neurocognitive disorders (HAND). Drug abuse increases extracellular dopamine in the CNS. Once in the brain, CD14+CD16+ monocytes can be exposed to extracellular dopamine due to drug abuse. The direct effects of dopamine on CD14+CD16+ monocytes and their contribution to HIV neuropathogenesis are not known. In this study, we showed that CD14+CD16+ monocytes express mRNA for all five dopamine receptors by qRT-PCR and D1R, D5R and D4R surface protein by flow cytometry. Dopamine and the D1-like dopamine receptor agonist, SKF38393, increased CD14+CD16+ monocyte migration that was characterized as chemokinesis. To determine whether dopamine affected cell motility and adhesion, live cell imaging was used to monitor the accumulation of CD14+CD16+ monocytes on the surface of a tissue culture dish. Dopamine increased the number and the rate at which CD14+CD16+ monocytes in suspension settled to the dish surface. In a spreading assay, dopamine increased the area of CD14+CD16+ monocytes during the early stages of cell adhesion. In addition, adhesion assays showed that the overall total number of adherent CD14+CD16+ monocytes increased in the presence of dopamine. These data suggest that elevated extracellular dopamine in the CNS of HIV infected drug abusers contributes to HIV neuropathogenesis by increasing the accumulation of CD14+CD16+ monocytes in dopamine rich brain

Effect of endogenous factors on the chemical perception of Grapholita molesta (Busck) (Lepidoptera: Tortricidae) to sex pheromone; Efeito de fatores endogenos na percepcao quimica de Grapholita molesta(Busck) (Lepidoptera: Tortricidae) ao feromonio sexual

Energy Technology Data Exchange (ETDEWEB)

Altafini, Deisi L.; Sant' Ana, Josue; Redaelli, Luiza R., E-mail: deisila@gmail.co [Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS (Brazil). Dept. de Fitossanidade. Programa de Pos-Graduacao em Fitotecnia

2010-06-15

The oriental fruit moth, Grapholita molesta (Busck), stands out as one of the most important pest in Rosaceae orchards in Brazil. During feeding, caterpillars bore into shoots, branches and fruits, impairing the commercial production. This work aimed to study the effect of endogenous factors in the chemical perception and in the species chemotactic behavior, seeking to optimize monitoring and the behavioral control of this pest. We evaluated male electroantennographical (EAG) and chemotactical (olfactometry) responses to the synthetic sex pheromone in different ages, virgins or mated and fed or unfed. The EAG responses of males did not differ for all evaluated factors. Nevertheless, the chemotactical behavior of males seems to decrease with age, not varying as a function of mating or feeding conditions. The knowledge about the interference of these factors in G. molesta may help with the interpretation of fi eld results, allowing the development of suitable and reliable control measures based on infochemicals for behavioral control. (author)

Monocyte-mediated delivery of polymeric backpacks to inflamed tissues: a generalized strategy to deliver drugs to treat inflammation.

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Anselmo, Aaron C; Gilbert, Jonathan B; Kumar, Sunny; Gupta, Vivek; Cohen, Robert E; Rubner, Michael F; Mitragotri, Samir

2015-02-10

Targeted delivery of drugs and imaging agents to inflamed tissues, as in the cases of cancer, Alzheimer's disease, Parkinson's disease, and arthritis, represents one of the major challenges in drug delivery. Monocytes possess a unique ability to target and penetrate into sites of inflammation. Here, we describe a broad approach to take advantage of the natural ability of monocytes to target and deliver flat polymeric particles ("Cellular Backpacks") to inflamed tissues. Cellular backpacks attach strongly to the surface of monocytes but do not undergo phagocytosis due to backpack's size, disk-like shape and flexibility. Following attachment of backpacks, monocytes retain important cellular functions including transmigration through an endothelial monolayer and differentiation into macrophages. In two separate in vivo inflammation models, backpack-laden monocytes exhibit increased targeting to inflamed tissues. Cellular backpacks, and their abilities to attach to monocytes without impairing monocyte functions and 'hitchhike' to a variety of inflamed tissues, offer a new platform for both cell-mediated therapies and broad targeting of inflamed tissues. Copyright © 2014 Elsevier B.V. All rights reserved.

Raman spectroscopy of individual monocytes reveals that single-beam optical trapping of mononuclear cells occurs by their nucleus

International Nuclear Information System (INIS)

Fore, Samantha; Chan, James; Taylor, Douglas; Huser, Thomas

2011-01-01

We show that laser tweezers Raman spectroscopy of eukaryotic cells with a significantly larger diameter than the tight focus of a single-beam laser trap leads to optical trapping of the cell by its optically densest part, i.e. typically the cell's nucleus. Raman spectra of individual optically trapped monocytes are compared with location-specific Raman spectra of monocytes adhered to a substrate. When the cell's nucleus is stained with a fluorescent live cell stain, the Raman spectrum of the DNA-specific stain is observed only in the nucleus of individual monocytes. Optically trapped monocytes display the same behavior. We also show that the Raman spectra of individual monocytes exhibit the characteristic Raman signature of cells that have not yet fully differentiated and that individual primary monocytes can be distinguished from transformed monocytes based on their Raman spectra. This work provides further evidence that laser tweezers Raman spectroscopy of individual cells provides meaningful biochemical information in an entirely non-destructive fashion that permits discerning differences between cell types and cellular activity

FGF23 inhibits extra-renal synthesis of 1,25-dihydroxyvitamin D in human monocytes

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Bacchetta, Justine; Sea, Jessica L; Chun, Rene F; Lisse, Thomas S; Wesseling-Perry, Katherine; Gales, Barbara; Adams, John S.; Salusky, Isidro B; Hewison, Martin

2012-01-01

Vitamin D is a potent stimulator of monocyte innate immunity, with this effect being mediated via intracrine conversion of 25-hydroxyvitamin D (25OHD) to 1,25-dihydroxyvitamin D (1,25(OH)2D). In the kidney synthesis of 1,25(OH)2D is suppressed by fibroblast growth factor 23 (FGF23), via transcriptional suppression of the vitamin D-activating enzyme 1α-hydroxylase (CYP27B1). We hypothesized that FGF23 also suppresses CYP27B1 in monocytes, with concomitant effects on intracrine responses to 1,25(OH)2D. Monocytes from healthy donor peripheral blood mononuclear cells (PBMCm) and from peritoneal dialysate effluent from kidney disease patients (PDm) were assessed at baseline to confirm the presence of mRNA for FGF23 receptors (FGFRs), with Klotho and FGFR1 being more strongly expressed than FGFR2/3/4 in both cell types. Immunohistochemistry showed co-expression of Klotho and FGFR1 in PBMCm and PDm, with this effect being enhanced following treatment with FGF23 in PBMCm but not PDm. Treatment with FGF23 activated MAP kinase (MAPK) and Akt pathways in PBMCm, demonstrating functional FGFR signaling in these cells. FGF23 treatment of PBMCm and PDm decreased expression of mRNA for CYP27B1. In PBMCm this was associated with downregulation of 25OHD to 1,25(OH)2D metabolism, and concomitant suppression of intracrine induced 24-hydroxylase (CYP24A1) and antibacterial cathelicidin (LL37). FGF23 suppression of CYP27B1 was particularly pronounced in PBMCm treated with interleukin-15 to stimulate synthesis of 1,25(OH)2D. These data indicate that FGF23 can inhibit extra-renal expression of CYP27B1 and subsequent intracrine responses to 1,25(OH)2D in two different human monocyte models. Elevated expression of FGF23 may therefore play a crucial role in defining immune responses to vitamin D and this, in turn, may be a key determinant of infection in patients with CKD. PMID:22886720

Virulent Type A Francisella tularensis actively suppresses cytokine responses in human monocytes

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Devyn D Gilette

2014-04-01

Full Text Available Francisella tularensis is a Gram-negative facultative bacterium that can cause the disease tularemia, even upon exposure to low numbers of bacteria. One critical characteristic of Francisella is its ability to dampen or subvert the host immune response. Previous work has shown that monocytes infected with highly virulent F. tularensis subsp. tularensis strain Schu S4 responded with a general pattern of quantitatively reduced pro-inflammatory signaling pathway genes and cytokine production in comparison to those infected with the less virulent related F. novicida. However, it has been unclear whether the virulent Schu S4 was merely evading or actively suppressing monocyte responses. By using mixed infection assays with F. tularensis and F. novicida, we show that F. tularensis actively suppresses monocyte pro-inflammatory responses. Additional experiments show that this suppression occurs in a dose-dependent manner and is dependent upon the viability of F. tularensis. Importantly, F. tularensis was able to suppress pro-inflammatory responses to earlier infections with F. novicida. These results lend support that F. tularensis actively dampens human monocyte responses and this likely contributes to its enhanced pathogenicity.

Maggot secretions skew monocyte-macrophage differentiation away from a pro-inflammatory to a pro-angiogenic type

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van der Plas, Mariena J A; van Dissel, Jaap T; Nibbering, Peter H

2009-01-01

BACKGROUND: Maggots of the blowfly Lucilia sericata are used for the treatment of chronic wounds. Earlier we reported maggot secretions to inhibit pro-inflammatory responses of human monocytes. The aim of this study was to investigate the effect of maggot secretions on the differentiation...... for 18 h. The expression of cell surface molecules and the levels of cytokines, chemokines and growth factors in supernatants were measured. Our results showed secretions to affect monocyte-macrophage differentiation leading to MØ-1 with a partial MØ-2-like morphology but lacking CD163, which...... is characteristic for MØ-2. In response to LPS or LTA, secretions-differentiated MØ-1 produced less pro-inflammatory cytokines (TNF-alpha, IL-12p40 and MIF) than control cells. Similar results were observed for MØ-2 when stimulated with low concentrations of LPS. Furthermore, secretions dose-dependently led to MØ-1...

Monocyte Proteomics Reveals Involvement of Phosphorylated HSP27 in the Pathogenesis of Osteoporosis

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Bhavna Daswani

2015-01-01

Full Text Available Peripheral monocytes, precursors of osteoclasts, have emerged as important candidates for identifying proteins relevant to osteoporosis, a condition characterized by low Bone Mineral Density (BMD and increased susceptibility for fractures. We employed 4-plex iTRAQ (isobaric tags for relative and absolute quantification coupled with LC-MS/MS (liquid chromatography coupled with tandem mass spectrometry to identify differentially expressed monocyte proteins from premenopausal and postmenopausal women with low versus high BMD. Of 1801 proteins identified, 45 were differentially abundant in low versus high BMD, with heat shock protein 27 (HSP27 distinctly upregulated in low BMD condition in both premenopausal and postmenopausal categories. Validation in individual samples (n=80 using intracellular ELISA confirmed that total HSP27 (tHSP27 as well as phosphorylated HSP27 (pHSP27 was elevated in low BMD condition in both categories (P<0.05. Further, using transwell assays, pHSP27, when placed in the upper chamber, could increase monocyte migration (P<0.0001 and this was additive in combination with RANKL (receptor activator of NFkB ligand placed in the lower chamber (P=0.05. Effect of pHSP27 in monocyte migration towards bone milieu can result in increased osteoclast formation and thus contribute to pathogenesis of osteoporosis. Overall, this study reveals for the first time a novel link between monocyte HSP27 and BMD.

Age-Related Gene Expression Differences in Monocytes from Human Neonates, Young Adults, and Older Adults.

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Lissner, Michelle M; Thomas, Brandon J; Wee, Kathleen; Tong, Ann-Jay; Kollmann, Tobias R; Smale, Stephen T

2015-01-01

A variety of age-related differences in the innate and adaptive immune systems have been proposed to contribute to the increased susceptibility to infection of human neonates and older adults. The emergence of RNA sequencing (RNA-seq) provides an opportunity to obtain an unbiased, comprehensive, and quantitative view of gene expression differences in defined cell types from different age groups. An examination of ex vivo human monocyte responses to lipopolysaccharide stimulation or Listeria monocytogenes infection by RNA-seq revealed extensive similarities between neonates, young adults, and older adults, with an unexpectedly small number of genes exhibiting statistically significant age-dependent differences. By examining the differentially induced genes in the context of transcription factor binding motifs and RNA-seq data sets from mutant mouse strains, a previously described deficiency in interferon response factor-3 activity could be implicated in most of the differences between newborns and young adults. Contrary to these observations, older adults exhibited elevated expression of inflammatory genes at baseline, yet the responses following stimulation correlated more closely with those observed in younger adults. Notably, major differences in the expression of constitutively expressed genes were not observed, suggesting that the age-related differences are driven by environmental influences rather than cell-autonomous differences in monocyte development.

PU.1 is essential for CD11c expression in CD8(+/CD8(- lymphoid and monocyte-derived dendritic cells during GM-CSF or FLT3L-induced differentiation.

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Xue-Jun Zhu

Full Text Available Dendritic cells (DCs regulate innate and acquired immunity through their roles as antigen-presenting cells. Specific subsets of mature DCs, including monocyte-derived and lymphoid-derived DCs, can be distinguished based on distinct immunophenotypes and functional properties. The leukocyte integrin, CD11c, is considered a specific marker for DCs and it is expressed by all DC subsets. We created a strain of mice in which DCs and their progenitors could be lineage traced based on activity of the CD11c proximal promoter. Surprisingly, we observed levels of CD11c promoter activity that were similar in DCs and in other mature leukocytes, including monocytes, granulocytes, and lymphocytes. We sought to identify DNA elements and transcription factors that regulate DC-associated expression of CD11c. The ets transcription factor, PU.1, is a key regulator of DC development, and expression of PU.1 varies in different DC subsets. GM-CSF increased monocyte-derived DCs in mice and from mouse bone marrow cultured in vitro, but it did not increase CD8(+ lymphoid-derived DCs or B220(+ plasmacytoid DCs. FLT3L increased both monocyte-derived DCs and lymphoid-derived DCs from mouse bone marrow cultured in vitro. GM-CSF increased the 5.3 Kb CD11c proximal promoter activity in monocyte-derived DCs and CD8(+ lymphoid-derived DCs, but not in B220(+ plasmacytoid DCs. In contrast, FLT3L increased the CD11c proximal promoter activity in both monocyte-derived DCs and B220(+ plasmacytoid DCs. We used shRNA gene knockdown and chromatin immunoprecipitation to demonstrate that PU.1 is required for the effects of GM-CSF or FLT3L on monocyte-derived DCs. We conclude that both GM-CSF and FLT3L act through PU.1 to activate the 5.3 Kb CD11c proximal promoter in DCs and to induce differentiation of monocyte-derived DCs. We also confirm that the CD11c proximal promoter is not sufficient to direct lineage specificity of CD11c expression, and that additional DNA elements are required

Endotoxin-induced monocytic microparticles have contrasting effects on endothelial inflammatory responses.

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Beryl Wen

Full Text Available Septic shock is a severe disease state characterised by the body's life threatening response to infection. Complex interactions between endothelial cells and circulating monocytes are responsible for microvasculature dysfunction contributing to the pathogenesis of this syndrome. Here, we intended to determine whether microparticles derived from activated monocytes contribute towards inflammatory processes and notably vascular permeability. We found that endotoxin stimulation of human monocytes enhances the release of microparticles of varying phenotypes and mRNA contents. Elevated numbers of LPS-induced monocytic microparticles (mMP expressed CD54 and contained higher levels of transcripts for pro-inflammatory cytokines such as TNF, IL-6 and IL-8. Using a prothrombin time assay, a greater reduction in plasma coagulation time was observed with LPS-induced mMP than with non-stimulated mMP. Co-incubation of mMP with the human brain endothelial cell line hCMEC/D3 triggered their time-dependent uptake and significantly enhanced endothelial microparticle release. Unexpectedly, mMP also modified signalling pathways by diminishing pSrc (tyr416 expression and promoted endothelial monolayer tightness, as demonstrated by endothelial impedance and permeability assays. Altogether, these data strongly suggest that LPS-induced mMP have contrasting effects on the intercellular communication network and display a dual potential: enhanced pro-inflammatory and procoagulant properties, together with protective function of the endothelium.

Human platelet lysate is a successful alternative serum supplement for propagation of monocyte-derived dendritic cells.

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Švajger, Urban

2017-04-01

Clinical protocols for dendritic cell (DC) generation from monocytes require the use of animal serum-free supplements. Serum-free media can also require up to 1% of serum supplementation. In addition, recommendations based on the 3Rs (Refinement, Reduction, Replacement) principle also recommend the use of non-animal sera in in vitro studies. The aim of this study was to explore the potential use of platelet lysate (PL) for generation of optimally differentiated DCs from monocytes. Cells were isolated from buffy coats from healthy volunteers using immunomagnetic selection. DCs were differentiated in RPMI1640 supplemented with either 10% fetal bovine serum (FBS), 10% AB serum or 10% PL with the addition of granulocyte monocyte colony stimulating factor and interleukin-4. Generated DCs were assessed for their morphology, viability, endocytotic capacity, surface phenotype (immature, mature and tolerogenic DCs) and activation of important signaling pathways. DC function was evaluated on the basis of their allostimulatory capacity, cytokine profile and ability to induce different T-helper subsets. DCs generated with PL displayed normal viability, morphology and endocytotic capacity. Their differentiation and maturation phenotype was comparable to FBS-cultured DCs. They showed functional plasticity and up-regulated tolerogenic markers in response to their environment. PL-cultured mature DCs displayed unhindered allostimulatory potential and the capacity to induce Th1 responses. The use of PL allowed for activation of crucial signaling proteins associated with DC differentiation and maturation. This study demonstrates for the first time that human PL represents a successful alternative to FBS in differentiation of DCs from monocytes. DCs display the major phenotypic and functional characteristics compared with existing culture protocols. Copyright © 2017 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

Facilitated monocyte-macrophage uptake and tissue distribution of superparmagnetic iron-oxide nanoparticles.

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Arnaud Beduneau

Full Text Available BACKGROUND: We posit that the same mononuclear phagocytes (MP that serve as target cells and vehicles for a host of microbial infections can be used to improve diagnostics and drug delivery. We also theorize that physical and biological processes such as particle shape, size, coating and opsonization that affect MP clearance of debris and microbes can be harnessed to facilitate uptake of nanoparticles (NP and tissue delivery. METHODS: Monocytes and monocyte-derived macrophages (MDM were used as vehicles of superparamagnetic iron oxide (SPIO NP and immunoglobulin (IgG or albumin coated SPIO for studies of uptake and distribution. IgG coated SPIO was synthesized by covalent linkage and uptake into monocytes and MDM investigated related to size, time, temperature, concentration, and coatings. SPIO and IgG SPIO were infused intravenously into naïve mice. T(2 measures using magnetic resonance imaging (MRI were used to monitor tissue distribution in animals. RESULTS: Oxidation of dextran on the SPIO surface generated reactive aldehyde groups and permitted covalent linkage to amino groups of murine and human IgG and F(ab'(2 fragments and for Alexa Fluor(R 488 hydroxylamine to form a Schiff base. This labile intermediate was immediately reduced with sodium cyanoborohydride in order to stabilize the NP conjugate. Optical density measurements of the oxidized IgG, F(ab'(2, and/or Alexa Fluor(R 488 SPIO demonstrated approximately 50% coupling yield. IgG-SPIO was found stable at 4 degrees C for a period of 1 month during which size and polydispersity index varied little from 175 nm and 200 nm, respectively. In vitro, NP accumulated readily within monocyte and MDM cytoplasm after IgG-SPIO exposure; whereas, the uptake of native SPIO in monocytes and MDM was 10-fold less. No changes in cell viability were noted for the SPIO-containing monocytes and MDM. Cell morphology was not changed as observed by transmission electron microscopy. Compared to unconjugated

LysoPC and PAF Trigger Arachidonic Acid Release by Divergent Signaling Mechanisms in Monocytes

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Janne Oestvang

2011-01-01

Full Text Available Oxidized low-density lipoproteins (LDLs play an important role during the development of atherosclerosis characterized by intimal inflammation and macrophage accumulation. A key component of LDL is lysophosphatidylcholine (lysoPC. LysoPC is a strong proinflammatory mediator, and its mechanism is uncertain, but it has been suggested to be mediated via the platelet activating factor (PAF receptor. Here, we report that PAF triggers a pertussis toxin- (PTX- sensitive intracellular signaling pathway leading to sequential activation of sPLA2, PLD, cPLA2, and AA release in human-derived monocytes. In contrast, lysoPC initiates two signaling pathways, one sequentially activating PLD and cPLA2, and a second parallel PTX-sensitive pathway activating cPLA2 with concomitant activation of sPLA2, all leading to AA release. In conclusion, lysoPC and PAF stimulate AA release by divergent pathways suggesting involvement of independent receptors. Elucidation of monocyte lysoPC-specific signaling mechanisms will aid in the development of novel strategies for atherosclerosis prevention, diagnosis, and therapy.

The kampo medicine Daikenchuto inhibits peritoneal fibrosis in mice.

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Kitamura, Mineaki; Nishino, Tomoya; Obata, Yoko; Oka, Satoru; Abe, Shinichi; Muta, Kumiko; Ozono, Yoshiyuki; Koji, Takehiko; Kohno, Shigeru

2015-01-01

Long-term peritoneal dialysis therapy causes inflammation and histological changes in the peritoneal membrane. Inflammation generally activates fibroblasts and results in fibroblast-myofibroblast differentiation. Heat-shock protein 47 (HSP 47), a collagen-specific molecular chaperone, is localized in myofibroblasts and is involved in the progression of peritoneal fibrosis. Daikenchuto (DKT), a Kampo medicine, is used to prevent postoperative colon adhesion. It inhibits inflammation and HSP 47 expression in the gastrointestinal tract. We examined the effect of DKT on chlorhexidine gluconate (CG)-induced peritoneal fibrosis in mice injected with 0.1% CG dissolved in 15% ethanol. DKT was dissolved in the drinking water. Histological changes were assessed using Masson trichrome staining. Cells expressing α-smooth muscle actin (α-SMA), HSP 47, phospho-Smad 2/3, F4/80, and monocyte chemotactic protein-1 were examined immunohistochemically. Compared with the control group, the peritoneal tissues of the CG group were markedly thickened, and the number of cells expressing α-SMA, HSP 47, phospho-Smad 2/3, F4/80, and monocyte chemotactic protein-1 was significantly increased. However, these changes were inhibited in the DKT-treated group. These results indicate that DKT can prevent peritoneal fibrosis by inhibiting inflammation and HSP 47 expression.

Presence of estrogen receptors in human myeloid monocytic cells (THP-1 cell line).

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Cutolo, M; Villaggio, B; Bisso, A; Sulli, A; Coviello, D; Dayer, J M

2001-01-01

To test THP-1 cells for the presence of estrogen receptors (ER) since studies have demonstrated in vivo and in vitro, the influence of estrogens on cells involved in immune response (i.e. macrophages), and since it has been demonstrated that human myeloid monocytic THP-1 cells acquire phenotypic and functional macrophage-like features after incubation with several cytokines or pharmacological agents. Stimulation of THP-1 cells with phorbol myristate acetate (PMA) to prompt their differentiation into macrophage-like cells and evaluation of the possible induction of ER. The expression of ER was analyzed by immunocytochemical assay, reverse transcriptase polymerase chain reaction (RT-PCR) and Western blot analysis. After stimulation by PMA, the human myeloid monocytic THP-1 cells showed the presence of ER, together with markers of monocytic cell differentiation such as CD68, CD54 and HLA-DR. Estrogen effects may be exerted directly through ER on monocytes/macrophages. PMA-treated THP-1 cells may constitute a useful in vitro model to determine the effects of estrogens on macrophage-like cells and their implications in the inflammatory and immune processes.

Tailored HIV-1 vectors for genetic modification of primary human dendritic cells and monocytes.

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Durand, Stéphanie; Nguyen, Xuan-Nhi; Turpin, Jocelyn; Cordeil, Stephanie; Nazaret, Nicolas; Croze, Séverine; Mahieux, Renaud; Lachuer, Joël; Legras-Lachuer, Catherine; Cimarelli, Andrea

2013-01-01

Monocyte-derived dendritic cells (MDDCs) play a key role in the regulation of the immune system and are the target of numerous gene therapy applications. The genetic modification of MDDCs is possible with human immunodeficiency virus type 1 (HIV-1)-derived lentiviral vectors (LVs) but requires high viral doses to bypass their natural resistance to viral infection, and this in turn affects their physiological properties. To date, a single viral protein is able to counter this restrictive phenotype, Vpx, a protein derived from members of the HIV-2/simian immunodeficiency virus SM lineage that counters at least two restriction factors present in myeloid cells. By tagging Vpx with a short heterologous membrane-targeting domain, we have obtained HIV-1 LVs incorporating high levels of this protein (HIV-1-Src-Vpx). These vectors efficiently transduce differentiated MDDCs and monocytes either as previously purified populations or as populations within unsorted peripheral blood mononuclear cells (PBMCs). In addition, these vectors can be efficiently pseudotyped with receptor-specific envelopes, further restricting their cellular tropism almost uniquely to MDDCs. Compared to conventional HIV-1 LVs, these novel vectors allow for an efficient genetic modification of MDDCs and, more importantly, do not cause their maturation or affect their survival, which are unwanted side effects of the transduction process. This study describes HIV-1-Src-Vpx LVs as a novel potent tool for the genetic modification of differentiated MDDCs and of circulating monocyte precursors with strong potential for a wide range of gene therapy applications.

Expansion of CD14+CD16+ monocytes producing TNF-α in complication-free diabetes type 1 juvenile onset patients.

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Myśliwska, Jolanta; Smardzewski, Marcin; Marek-Trzonkowska, Natalia; Myśliwiec, Małgorzata; Raczyńska, Krystyna

2012-10-01

We concentrated on the complication-free phase of juvenile onset type 1 diabetes mellitus (T1DM) searching for associations between concentration of inflammatory factors TNF-α, CRP and VEGF and two monocyte subsets the CD14(++)CD16(-) and CD14(+)CD16(+). We analysed a randomly selected group of 150 patients without complications (disease duration 2.74 ± 2.51 years) at the start of the project and 5 years later. They were compared with 24 patients with retinopathy (6.53 ± 3.39 years of disease) and 30 healthy volunteers. Our results indicate that in the complication-free period the concentration of TNF-α significantly increased and continued to increase after retinopathy was established. After 5 years the percentage and absolute number of CD14(+)CD16(+) monocytes doubled in complication-free patients. Our study indicates that the size of CD14(+)CD16(+) monocyte subset may be used alternatively to CRP values as an indicator of inflammation grade. Our results imply the necessity of trials using anti-TNF-α therapy in the complication-free phase of the disease. Copyright © 2012 Elsevier Ltd. All rights reserved.

Polystyrene-Divinylbenzene-Based Adsorbents Reduce Endothelial Activation and Monocyte Adhesion Under Septic Conditions in a Pore Size-Dependent Manner.

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Eichhorn, Tanja; Rauscher, Sabine; Hammer, Caroline; Gröger, Marion; Fischer, Michael B; Weber, Viktoria

2016-10-01

Endothelial activation with excessive recruitment and adhesion of immune cells plays a central role in the progression of sepsis. We established a microfluidic system to study the activation of human umbilical vein endothelial cells by conditioned medium containing plasma from lipopolysaccharide-stimulated whole blood or from septic blood and to investigate the effect of adsorption of inflammatory mediators on endothelial activation. Treatment of stimulated whole blood with polystyrene-divinylbenzene-based cytokine adsorbents (average pore sizes 15 or 30 nm) prior to passage over the endothelial layer resulted in significantly reduced endothelial cytokine and chemokine release, plasminogen activator inhibitor-1 secretion, adhesion molecule expression, and in diminished monocyte adhesion. Plasma samples from sepsis patients differed substantially in their potential to induce endothelial activation and monocyte adhesion despite their almost identical interleukin-6 and tumor necrosis factor-alpha levels. Pre-incubation of the plasma samples with a polystyrene-divinylbenzene-based adsorbent (30 nm average pore size) reduced endothelial intercellular adhesion molecule-1 expression to baseline levels, resulting in significantly diminished monocyte adhesion. Our data support the potential of porous polystyrene-divinylbenzene-based adsorbents to reduce endothelial activation under septic conditions by depletion of a broad range of inflammatory mediators.

Plasminogen activator inhibitor-2 in patients with monocytic leukemia.

Science.gov (United States)

Scherrer, A; Kruithof, E K; Grob, J P

1991-06-01

Plasma and tumor cells from 103 patients with leukemia or lymphoma at initial presentation were investigated for the presence of plasminogen activator inhibitor-2 (PAI-2) antigen, a potent inhibitor of urokinase. PAI-2 was detected in plasma and leukemic cells of the 21 patients with leukemia having a monocytic component [acute myelomonocytic (M4), acute monoblastic (M5), and chronic myelomonocytic leukemias], and in the three patients with acute undifferentiated myeloblastic leukemia (M0). In contrast, this serine protease inhibitor was undetectable in 79 patients with other subtypes of acute myeloid leukemia or other hematological malignancies. Serial serum PAI-2 determinations in 16 patients with acute leukemia at presentation, during therapy, remission, and relapse revealed that in the five patients with M4-M5, elevated PAI-2 levels rapidly normalized under therapy and during remission, but increased again in the patients with a relapse associated with an M4-M5 phenotype. Thus, PAI-2 seems to be a marker highly specific for the active stages of monocytic leukemia, i.e. presentation and relapse. The presence of PAI-2 in the plasma and cells of patients with M0 may give a clue to a monocytic origin of these cells.

Differential oxidative stress induced by dengue virus in monocytes from human neonates, adult and elderly individuals.

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Nereida Valero

Full Text Available Changes in immune response during lifespan of man are well known. These changes involve decreased neonatal and elderly immune response. In addition, it has been shown a relationship between immune and oxidative mechanisms, suggesting that altered immune response could be associated to altered oxidative response. Increased expression of nitric oxide (NO has been documented in dengue and in monocyte cultures infected with different types of dengue virus. However, there is no information about the age-dependent NO oxidative response in humans infected by dengue virus. In this study, monocyte cultures from neonatal, elderly and adult individuals (n = 10 each group were infected with different dengue virus types (DENV- 1 to 4 and oxidative/antioxidative responses and apoptosis were measured at days 1 and 3 of culture. Increased production of NO, lipid peroxidation and enzymatic and nonenzymatic anti-oxidative responses in dengue infected monocyte cultures were observed. However, neonatal and elderly monocytes had lower values of studied parameters when compared to those in adult-derived cultures. Apoptosis was present in infected monocytes with higher values at day 3 of culture. This reduced oxidant/antioxidant response of neonatal and elderly monocytes could be relevant in the pathogenesis of dengue disease.

Functional contribution of elevated circulating and hepatic non-classical CD14CD16 monocytes to inflammation and human liver fibrosis.

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Henning W Zimmermann

Full Text Available BACKGROUND: Monocyte-derived macrophages critically perpetuate inflammatory responses after liver injury as a prerequisite for organ fibrosis. Experimental murine models identified an essential role for the CCR2-dependent infiltration of classical Gr1/Ly6C(+ monocytes in hepatic fibrosis. Moreover, the monocyte-related chemokine receptors CCR1 and CCR5 were recently recognized as important fibrosis modulators in mice. In humans, monocytes consist of classical CD14(+CD16(- and non-classical CD14(+CD16(+ cells. We aimed at investigating the relevance of monocyte subpopulations for human liver fibrosis, and hypothesized that 'non-classical' monocytes critically exert inflammatory as well as profibrogenic functions in patients during liver disease progression. METHODOLOGY/PRINCIPAL FINDINGS: We analyzed circulating monocyte subsets from freshly drawn blood samples of 226 patients with chronic liver disease (CLD and 184 healthy controls by FACS analysis. Circulating monocytes were significantly expanded in CLD-patients compared to controls with a marked increase of the non-classical CD14(+CD16(+ subset that showed an activated phenotype in patients and correlated with proinflammatory cytokines and clinical progression. Correspondingly, CD14(+CD16(+ macrophages massively accumulated in fibrotic/cirrhotic livers, as evidenced by immunofluorescence and FACS. Ligands of monocyte-related chemokine receptors CCR2, CCR1 and CCR5 were expressed at higher levels in fibrotic and cirrhotic livers, while CCL3 and CCL4 were also systemically elevated in CLD-patients. Isolated monocyte/macrophage subpopulations were functionally characterized regarding cytokine/chemokine expression and interactions with primary human hepatic stellate cells (HSC in vitro. CD14(+CD16(+ monocytes released abundant proinflammatory cytokines. Furthermore, CD14(+CD16(+, but not CD14(+CD16(- monocytes could directly activate collagen-producing HSC. CONCLUSIONS/SIGNIFICANCE: Our data

Monocytes from cystic fibrosis patients are locked in an LPS tolerance state: down-regulation of TREM-1 as putative underlying mechanism.

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Carlos del Fresno

Full Text Available Cystic Fibrosis (CF is an inherited pleiotropic disease that results from abnormalities in the gene that codes for the chloride channel, Cystic Fibrosis Transmembrane Conductance Regulator (CFTR. CF patients are frequently colonized by several pathogens, but the mechanisms that allow colonization in spite of apparently functional immune systems are incompletely understood. In this paper we show that blood peripheral monocytes isolated from CF patients are found in an endotoxin tolerance state, yet this is not due to a deficient TLR activation. On the other hand, levels of the amplifier of inflammatory responses, TREM-1 (Triggering Receptor Expressed on Myeloid cells, are notably down-regulated in monocytes from patients, in comparison to those extracted from healthy volunteers. Furthermore, the soluble form of TREM-1 (sTREM-1 was not detected in the sera of patients. Additionally, and in strict contrast to patients who suffer from Chronic Obstructive Pulmonary Disease (COPD, CF monocytes challenged ex vivo with LPS neither up-regulated membrane-anchored TREM-1 nor sTREM-1. Finally, similar levels of PGE(2 expression and p65 translocation into the nucleus were found in both patients and healthy volunteers, thus suggesting that TREM-1 regulation is neither controlled by PGE(2 levels nor by p65 activation in this case. However, PU.1 translocation into the nucleus was significantly higher in CF monocytes than in controls, suggesting a role for this transcription factor in the control of TREM-1 expression. We conclude that down-regulation of TREM-1 expression in cystic fibrosis patients is at least partly responsible for the endotoxin tolerance state in which their monocytes are locked.

Leishmania infection modulates beta-1 integrin activation and alters the kinetics of monocyte spreading over fibronectin

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Figueira, Cláudio Pereira; Carvalhal, Djalma Gomes Ferrão; Almeida, Rafaela Andrade; Hermida, Micely d’ El-Rei; Touchard, Dominique; Robert, Phillipe; Pierres, Anne; Bongrand, Pierre; dos-Santos, Washington LC

2015-01-01

Contact with Leishmania leads to a decreases in mononuclear phagocyte adherence to connective tissue. In this work, we studied the early stages of bond formation between VLA4 and fibronectin, measured the kinetics of membrane alignment and the monocyte cytoplasm spreading area over a fibronectin-coated surface, and studied the expression of high affinity integrin epitope in uninfected and Leishmania-infected human monocytes. Our results show that the initial VLA4-mediated interaction of Leishmania-infected monocyte with a fibronectin-coated surface is preserved, however, the later stage, leukocyte spreading over the substrate is abrogated in Leishmania-infected cells. The median of spreading area was 72 [55–89] μm2 for uninfected and 41 [34–51] μm2 for Leishmania-infected monocyte. This cytoplasm spread was inhibited using an anti-VLA4 blocking antibody. After the initial contact with the fibronectrin-coated surface, uninfected monocyte quickly spread the cytoplasm at a 15 μm2 s−1 ratio whilst Leishmania-infected monocytes only made small contacts at a 5.5 μm2 s−1 ratio. The expression of high affinity epitope by VLA4 (from 39 ± 21% to 14 ± 3%); and LFA1 (from 37 ± 32% to 18 ± 16%) molecules was reduced in Leishmania-infected monocytes. These changes in phagocyte function may be important for parasite dissemination and distribution of lesions in leishmaniasis. PMID:26249106

Unlike PPARγ, PPARα or PPARβ/δ activation does not promote human monocyte differentiation toward alternative macrophages

International Nuclear Information System (INIS)

Bouhlel, Mohamed Amine; Brozek, John; Derudas, Bruno; Zawadzki, Christophe; Jude, Brigitte; Staels, Bart; Chinetti-Gbaguidi, Giulia

2009-01-01

Macrophages adapt their response to micro-environmental signals. While Th1 cytokines promote pro-inflammatory M1 macrophages, Th2 cytokines promote an 'alternative' anti-inflammatory M2 macrophage phenotype. Peroxisome proliferator-activated receptors (PPARs) are ligand-activated transcription factors expressed in macrophages where they control the inflammatory response. It has been shown that PPARγ promotes the differentiation of monocytes into anti-inflammatory M2 macrophages in humans and mice, while a role for PPARβ/δ in this process has been reported only in mice and no data are available for PPARα. Here, we show that in contrast to PPARγ, expression of PPARα and PPARβ/δ overall does not correlate with the expression of M2 markers in human atherosclerotic lesions, whereas a positive correlation with genes of lipid metabolism exists. Moreover, unlike PPARγ, PPARα or PPARβ/δ activation does not influence human monocyte differentiation into M2 macrophages in vitro. Thus, PPARα and PPARβ/δ do not appear to modulate the alternative differentiation of human macrophages.

Monocyte Locomotion Inhibitory Factor Produced by E. histolytica Improves Motor Recovery and Develops Neuroprotection after Traumatic Injury to the Spinal Cord

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Bermeo, Gabriela; García, Elisa; Flores-Romero, Adrian; Rico-Rosillo, Guadalupe; Marroquín, Rubén; Flores, Carmina; Blanco-Favela, Francisco; Silva-García, Raúl

2013-01-01

Monocyte locomotion inhibitory factor (MLIF) is a pentapeptide produced by Entamoeba histolytica that has a potent anti-inflammatory effect. Either MLIF or phosphate buffered saline (PBS) was administered directly onto the spinal cord (SC) immediately after injury. Motor recovery was evaluated. We also analyzed neuroprotection by quantifying the number of surviving ventral horn motor neurons and the persistence of rubrospinal tract neurons. To evaluate the mechanism through which MLIF improved the outcome of SC injury, we quantified the expression of inducible nitric oxide synthase (iNOS), interleukin-10 (IL-10), and transforming growth factor-β (TGF-β) genes at the site of injury. Finally, the levels of nitric oxide and of lipid peroxidation were also determined in peripheral blood. Results showed that MLIF improved the rate of motor recovery and this correlated with an increased survival of ventral horn and rubrospinal neurons. These beneficial effects were in turn associated with a reduction in iNOS gene products and a significant upregulation of IL-10 and TGF-β expression. In the same way, MLIF reduced the concentration of nitric oxide and the levels of lipid peroxidation in systemic circulation. The present results demonstrate for the first time the neuroprotective effects endowed by MLIF after SC injury. PMID:24294606

Phenotypic and functional modulation of porcine monocyte-derived ...

African Journals Online (AJOL)

Jane

2011-08-08

Aug 8, 2011 ... monocyte-derived dendritic cells for foot-and-mouth disease virus. Hai-yan Shen1# ... tissues, to migrate to secondary lymphoid organs and to provide the ... innate and adaptive immune responses mentioned earlier led us to ...

The effect of insulin resistance and exercise on the percentage of CD16(+) monocyte subset in obese individuals.

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de Matos, Mariana A; Duarte, Tamiris C; Ottone, Vinícius de O; Sampaio, Pâmela F da M; Costa, Karine B; de Oliveira, Marcos F Andrade; Moseley, Pope L; Schneider, Suzanne M; Coimbra, Cândido C; Brito-Melo, Gustavo E A; Magalhães, Flávio de C; Amorim, Fabiano T; Rocha-Vieira, Etel

2016-06-01

Obesity is a low-grade chronic inflammation condition, and macrophages, and possibly monocytes, are involved in the pathological outcomes of obesity. Physical exercise is a low-cost strategy to prevent and treat obesity, probably because of its anti-inflammatory action. We evaluated the percentage of CD16(-) and CD16(+) monocyte subsets in obese insulin-resistant individuals and the effect of an exercise bout on the percentage of these cells. Twenty-seven volunteers were divided into three experimental groups: lean insulin sensitive, obese insulin sensitive and obese insulin resistant. Venous blood samples collected before and 1 h after an aerobic exercise session on a cycle ergometer were used for determination of monocyte subsets by flow cytometry. Insulin-resistant obese individuals have a higher percentage of CD16(+) monocytes (14.8 ± 2.4%) than the lean group (10.0 ± 1.3%). A positive correlation of the percentage of CD16(+) monocytes with body mass index and fasting plasma insulin levels was found. One bout of moderate exercise reduced the percentage of CD16(+) monocytes by 10% in all the groups evaluated. Also, the absolute monocyte count, as well as all other leukocyte populations, in lean and obese individuals, increased after exercise. This fact may partially account for the observed reduction in the percentage of CD16(+) cells in response to exercise. Insulin-resistant, but not insulin-sensitive obese individuals, have an increased percentage of CD16(+) monocytes that can be slightly modulated by a single bout of moderate aerobic exercise. These findings may be clinically relevant to the population studied, considering the involvement of CD16(+) monocytes in the pathophysiology of obesity. Copyright © 2016 John Wiley & Sons, Ltd. Obesity is now considered to be an inflammatory condition associated with many pathological consequences, including insulin resistance. It is proposed that insulin resistance contributes to the aggravation of the

Pro-inflammatory capacity of classically activated monocytes relates positively to muscle mass and strength.

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Beenakker, Karel G M; Westendorp, Rudi G J; de Craen, Anton J M; Slagboom, Pieternella E; van Heemst, Diana; Maier, Andrea B

2013-08-01

In mice, monocytes that exhibit a pro-inflammatory profile enter muscle tissue after muscle injury and are crucial for clearance of necrotic tissue and stimulation of muscle progenitor cell proliferation and differentiation. The aim of this study was to test if pro-inflammatory capacity of classically activated (M1) monocytes relates to muscle mass and strength in humans. This study included 191 male and 195 female subjects (mean age 64.2 years (SD 6.4) and 61.9 ± 6.4, respectively) of the Leiden Longevity Study. Pro-inflammatory capacity of M1 monocytes was assessed by ex vivo stimulation of whole blood with Toll-like receptor (TLR) 4 agonist lipopolysaccharide (LPS) and TLR-2/1 agonist tripalmitoyl-S-glycerylcysteine (Pam₃Cys-SK₄), both M1 phenotype activators. Cytokines that stimulate M1 monocyte response (IFN-γ and GM-CSF) as well as cytokines that are secreted by M1 monocytes (IL-6, TNF-α, IL-12, and IL-1β) were measured. Analyses were adjusted for age, height, and body fat mass. Upon stimulation with LPS, the cytokine production capacity of INF-γ, GM-CSF, and TNF-α was significantly positively associated with lean body mass, appendicular lean mass and handgrip strength in men, but not in women. Upon stimulation with Pam₃Cys-SK₄, IL-6; TNF-α; and Il-1β were significantly positively associated with lean body mass and appendicular lean in women, but not in men. Taken together, this study shows that higher pro-inflammatory capacity of M1 monocytes upon stimulation is associated with muscle characteristics and sex dependent. © 2013 John Wiley & Sons Ltd and the Anatomical Society.

alpha-MSH and its receptors in regulation of tumor necrosis factor-alpha production by human monocyte/macrophages.

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Taherzadeh, S; Sharma, S; Chhajlani, V; Gantz, I; Rajora, N; Demitri, M T; Kelly, L; Zhao, H; Ichiyama, T; Catania, A; Lipton, J M

1999-05-01

The hypothesis that macrophages contain an autocrine circuit based on melanocortin [ACTH and alpha-melanocyte-stimulating hormone (alpha-MSH)] peptides has major implications for neuroimmunomodulation research and inflammation therapy. To test this hypothesis, cells of the THP-1 human monocyte/macrophage line were stimulated with lipopolysaccharide (LPS) in the presence and absence of alpha-MSH. The inflammatory cytokine tumor necrosis factor (TNF)-alpha was inhibited in relation to alpha-MSH concentration. Similar inhibitory effects on TNF-alpha were observed with ACTH peptides that contain the alpha-MSH amino acid sequence and act on melanocortin receptors. Nuclease protection assays indicated that expression of the human melanocortin-1 receptor subtype (hMC-1R) occurs in THP-1 cells; Southern blots of RT-PCR product revealed that additional subtypes, hMC-3R and hMC-5R, also occur. Incubation of resting macrophages with antibody to hMC-1R increased TNF-alpha concentration; the antibody also markedly reduced the inhibitory influence of alpha-MSH on TNF-alpha in macrophages treated with LPS. These results in cells known to produce alpha-MSH at rest and to increase secretion of the peptide when challenged are consistent with an endogenous regulatory circuit based on melanocortin peptides and their receptors. Targeting of this neuroimmunomodulatory circuit in inflammatory diseases in which myelomonocytic cells are prominent should be beneficial.

Soluble fibrin inhibits monocyte adherence and cytotoxicity against tumor cells: implications for cancer metastasis

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Patel Shonak

2006-08-01

Full Text Available Abstract Background Soluble fibrin (sFn is a marker for disseminated intravascular coagulation and may have prognostic significance, especially in metastasis. However, a role for sFn in the etiology of metastatic cancer growth has not been extensively studied. We have reported that sFn cross-linked platelet binding to tumor cells via the major platelet fibrin receptor αIIbβ3, and tumor cell CD54 (ICAM-1, which is the receptor for two of the leukocyte β2 integrins (αLβ2 and aMβ2. We hypothesized that sFn may also affect leukocyte adherence, recognition, and killing of tumor cells. Furthermore, in a rat experimental metastasis model sFn pre-treatment of tumor cells enhanced metastasis by over 60% compared to untreated cells. Other studies have shown that fibrin(ogen binds to the monocyte integrin αMβ2. This study therefore sought to investigate the effect of sFn on β2 integrin mediated monocyte adherence and killing of tumor cells. Methods The role of sFn in monocyte adherence and cytotoxicity against tumor cells was initially studied using static microplate adherence and cytotoxicity assays, and under physiologically relevant flow conditions in a microscope perfusion incubator system. Blocking studies were performed using monoclonal antibodies specific for β2 integrins and CD54, and specific peptides which inhibit sFn binding to these receptors. Results Enhancement of monocyte/tumor cell adherence was observed when only one cell type was bound to sFn, but profound inhibition was observed when sFn was bound to both monocytes and tumor cells. This effect was also reflected in the pattern of monocyte cytotoxicity. Studies using monoclonal blocking antibodies and specific blocking peptides (which did not affect normal coagulation showed that the predominant mechanism of fibrin inhibition is via its binding to αMβ2 on monocytes, and to CD54 on both leukocytes and tumor cells. Conclusion sFn inhibits monocyte adherence and cytotoxicity of

CD16+ Monocytes and Skewed Macrophage Polarization toward M2 Type Hallmark Heart Transplant Acute Cellular Rejection

OpenAIRE

van den Bosch, Thierry P. P.; Caliskan, Kadir; Kraaij, Marina D.; Constantinescu, Alina A.; Manintveld, Olivier C.; Leenen, Pieter J. M.; von der Th?sen, Jan H.; Clahsen-van Groningen, Marian C.; Baan, Carla C.; Rowshani, Ajda T.

2017-01-01

textabstractBackground: During acute heart transplant rejection, infiltration of lymphocytes and monocytes is followed by endothelial injury and eventually myocardial fibrosis. To date, no information is available on monocyte-macrophage-related cellular shifts and their polarization status during rejection. Here, we aimed to define and correlate monocyte-macrophage endomyocardial tissue profiles obtained at rejection and time points prior to rejection, with corresponding serial blood samples ...

Human monocytes undergo excessive apoptosis following temozolomide activating the ATM/ATR pathway while dendritic cells and macrophages are resistant.

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Martina Bauer

Full Text Available Immunodeficiency is a severe therapy-limiting side effect of anticancer chemotherapy resulting from sensitivity of immunocompetent cells to DNA damaging agents. A central role in the immune system is played by monocytes that differentiate into macrophages and dendritic cells (DCs. In this study we compared human monocytes isolated from peripheral blood and cytokine matured macrophages and DCs derived from them and assessed the mechanism of toxicity of the DNA methylating anticancer drug temozolomide (TMZ in these cell populations. We observed that monocytes, but not DCs and macrophages, were highly sensitive to the killing effect of TMZ. Studies on DNA damage and repair revealed that the initial DNA incision was efficient in monocytes while the re-ligation step of base excision repair (BER can not be accomplished, resulting in an accumulation of DNA single-strand breaks (SSBs. Furthermore, monocytes accumulated DNA double-strand breaks (DSBs following TMZ treatment, while DCs and macrophages were able to repair DSBs. Monocytes lack the DNA repair proteins XRCC1, ligase IIIα and PARP-1 whose expression is restored during differentiation into macrophages and DCs following treatment with GM-CSF and GM-CSF plus IL-4, respectively. These proteins play a key role both in BER and DSB repair by B-NHEJ, which explains the accumulation of DNA breaks in monocytes following TMZ treatment. Although TMZ provoked an upregulation of XRCC1 and ligase IIIα, BER was not enhanced likely because PARP-1 was not upregulated. Accordingly, inhibition of PARP-1 did not sensitize monocytes, but monocyte-derived DCs in which strong PARP activation was observed. TMZ induced in monocytes the DNA damage response pathways ATM-Chk2 and ATR-Chk1 resulting in p53 activation. Finally, upon activation of the Fas-receptor and the mitochondrial pathway apoptosis was executed in a caspase-dependent manner. The downregulation of DNA repair in monocytes, resulting in their selective

Expression of EMAP-II in the rat dental follicle and its potential role in tooth eruption

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Liu, Dawen; Wise, Gary E.

2008-01-01

Endothelial monocyte-activating polypeptide II (EMAP-II) is an inflammatory cytokine with chemotactic activity. Because the dental follicle (DF) recruits mononuclear cells (osteoclast precursors) to promote the osteoclastogenesis needed for tooth eruption, it was the aim of this study to determine if EMAP-II may contribute to this recruitment. Using a DNA microarray, EMAP-II was found to be highly expressed in vivo in the DFs of day 1 to day 11 postnatal rats, with its expression elevated at days 1 and 3. Using a siRNA to knock down EMAP-II expression also resulted in a reduction in expression of CSF-1 and MCP-1 in the DF cells. Addition of EMAP-II protein to the DF cells partially restored the expression of CSF-1 and MCP-1. In chemotaxis assays using either conditioned medium of the DF cells with anti-EMAP-II antibody added or conditioned medium of DF cells with EMAP-II knocked down by siRNA, migration indexes of bone marrow mononuclear cells were significantly reduced. These results suggest that EMAP-II is another chemotactic molecule in the dental follicle involved in recruitment of mononuclear cells, and that EMAP-II may exert its chemotactic function directly by recruiting mononuclear cells and indirectly by enhancing the expression of other chemotactic molecules (CSF-1 and MCP-1). PMID:18705801

Decreased glucose uptake by hyperglycemia is regulated by different mechanisms in human cancer cells and monocytes

International Nuclear Information System (INIS)

Kim, Chae Kyun; Chung, June Key; Lee, Yong Jin; Hong, Mee Kyoung; Jeong, Jae Min; Lee, Dong Soo; Lee, Myung Chul

2002-01-01

To clarify the difference in glucose uptake between human cancer cells and monocytes, we studied ( 18 F) fluorodeoxyglucose (FDG) uptake in three human colon cancer cell lines (SNU-C2A, SNU-C4, SNU-C5), one human lung cancer cell line (NCI-H522), and human peripheral blood monocytes. The FDG uptake of both cancer cells and monocytes was increased in glucose-free medium, but decreased in the medium containing 16.7 mM glucose (hyperglycemic). The level of Glut1 mRNA decreased in human colon cancer cells and NCI-H522 under hyperglycemic condition. Glut1 protein expression was also decreased in the four human cancer cell lines under hyperglycemic condition, whereas it was consistently undetectable in monocytes. SNU-C2A, SNU-C4 and NCI-H522 showed a similar level of hexokinase activity (7.5-10.8 mU/mg), while SNU-C5 and moncytes showed lower range of hexokinase activity (4.3-6.5 mU/mg). These data suggest that glucose uptake is regulated by different mechanisms in human cancer cells and monocytes

ALV-J infection induces chicken monocyte death accompanied with the production of IL-1β and IL-18.

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Dai, Manman; Feng, Min; Xie, Tingting; Li, Yuanfang; Ruan, Zhuohao; Shi, Meiqing; Liao, Ming; Zhang, Xiquan

2017-11-21

Immunosuppression induced by avian leukosis virus subgroup J (ALV-J) causes serious reproduction problems and secondary infections in chickens. Given that monocytes are important precursors of immune cells including macrophages and dendritic cells, we investigated the fate of chicken monocytes after ALV-J infection. Our results indicated that most monocytes infected with ALV-J including field or laboratory strains could not successfully differentiate into macrophages due to cells death. And cells death was dependent upon viral titer and accompanied with increased IL-1β and IL-18 mRNA levels. In addition, ALV-J infection up-regulated caspase-1 and caspase-3 activity in monocytes. Collectively, we found that ALV-J could cause cell death in chicken monocytes, especially pyroptosis, which may be a significant reason for ALV-J induced immunosuppression.

Src Family Kinases Regulate Interferon Regulatory Factor 1 K63 Ubiquitination following Activation by TLR7/8 Vaccine Adjuvant in Human Monocytes and B Cells

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Lorenza Tulli

2018-03-01

Full Text Available Toll-like receptors (TLRs play a key role in the activation of innate immune cells, in which their engagement leads to production of cytokines and co-stimulatory molecules. TLRs signaling requires recruitment of toll/IL-1R (TIR domain-containing adaptors, such as MyD88 and/or TRIF, and leads to activation of several transcription factors, such as NF-κB, the AP1 complex, and various members of the interferon regulatory factor (IRF family, which in turn results in triggering of several cellular functions associated with these receptors. A role for Src family kinases (SFKs in this signaling pathway has also been established. Our work and that of others have shown that this type of kinases is activated following engagement of several TLRs, and that this event is essential for the initiation of specific downstream cellular response. In particular, we have previously demonstrated that activation of SFKs is required for balanced production of pro-inflammatory cytokines by monocyte-derived dendritic cells after stimulation with R848, an agonist of human TLRs 7/8. We also showed that TLR7/8 triggering leads to an increase in interferon regulatory factor 1 (IRF-1 protein levels and that this effect is abolished by inhibition of SFKs, suggesting a critical role of these kinases in IRF-1 regulation. In this study, we first confirmed the key role of SFKs in TLR7/8 signaling for cytokine production and accumulation of IRF-1 protein in monocytes and in B lymphocytes, two other type of antigen-presenting cells. Then, we demonstrate that TLR7 triggering leads to an increase of K63-linked ubiquitination of IRF-1, which is prevented by SFKs inhibition, suggesting a key role of these kinases in posttranslational regulation of IRF-1 in the immune cells. In order to understand the mechanism that links SFKs activation to IRF-1 K63-linked ubiquitination, we examined SFKs and IRF-1 possible interactors and proved that activation of SFKs is necessary for their

Enhanced interleukin-8 production in THP-1 human monocytic cells by lipopolysaccharide from oral microorganisms and granulocyte-macrophage colony-stimulating factor.

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Baqui, A A; Meiller, T F; Falkler, W A

1999-10-01

Granulocyte-macrophage colony-stimulating factor (GM-CSF) has been used to assist in bone marrow recovery during cancer chemotherapy. Interleukin-8 (IL-8) plays an important role in macrophage mediated inflammatory processes including exacerbation of periodontal diseases, one of the most common complications in GM-CSF receiving cancer patients. The effect of GM-CSF supplementation on IL-8 production was investigated in a human monocyte cell line THP-1, stimulated with lipopolysaccharide extracted from two oral microorganisms, Porphyromonas gingivalis and Fusobacterium nucleatum. Resting THP-1 cells were treated with lipopolysaccharide (1 microgram/ml) of P. gingivalis or F. nucleatum and/or GM-CSF (50 IU/ml) for varying time periods. The production of IL-8 in THP-1 cells was measured by a solid-phase enzyme-linked immunosorbent assay (ELISA). A very low level of the cytokine IL-8 was produced constitutive in THP-1 cells. Starting from 8 h of treatment and afterwards GM-CSF alone significantly increased IL-8 production in THP-1 cells. Lipopolysaccharide (1 microgram/ml) extracts from either F. nucleatum or P. gingivalis amplified IL-8 production 500-800 times in comparison to resting THP-1 cells. When lipopolysaccharide of F. nucleatum or P. gingivalis was supplemented with 50 IU/ml of GM-CSF, there was a statistically significant enhanced production of IL-8 by THP-1 cells after 1 day to 7 days of treatment as compared with lipopolysaccharide treatment alone. GM-CSF (50 IU/ml) also significantly increased IL-8 production from 2-7 days of treatment of THP-1 cells when supplemented with a positive control, phorbol-12-myristate-13 acetate (PMA), as compared to PMA treatment alone. These investigations using the in vitro THP-1 human monocyte cell model indicate that there may be an increase in the response on a cellular level to oral endotoxin following GM-CSF therapy as evidenced by enhanced production of the tissue-reactive inflammatory cytokine, IL-8.

Activated human mast cells induce LOX-1-specific scavenger receptor expression in human monocyte-derived macrophages.

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Mervi Alanne-Kinnunen

Full Text Available Activated mast cells in atherosclerotic lesions degranulate and release bioactive compounds capable of regulating atherogenesis. Here we examined the ability of activated human primary mast cells to regulate the expression of the major scavenger receptors in cultured human primary monocyte-derived macrophages (HMDMs.Components released by immunologically activated human primary mast cells induced a transient expression of lectin-like oxidized LDL receptor (LOX-1 mRNA in HMDMs, while the expression of two other scavenger receptors, MSR1 and CD36, remained unaffected. The LOX-1-inducing secretory components were identified as histamine, tumor necrosis factor alpha (TNF-α, and transforming growth factor beta (TGF-β1, which exhibited a synergistic effect on LOX-1 mRNA expression. Histamine induced a transient expression of LOX-1 protein. Mast cell -induced increase in LOX-1 expression was not associated with increased uptake of oxidized LDL by the macrophages.Mast cell-derived histamine, TNF-α, and TGF-β1 act in concert to induce a transient increase in LOX-1 expression in human primary monocyte-derived macrophages. The LOX-1-inducing activity potentially endows mast cells a hitherto unrecognized role in the regulation of innate immune reactions in atherogenesis.

DMPD: Monocyte CD14: a multifunctional receptor engaged in apoptosis from both sides. [Dynamic Macrophage Pathway CSML Database

Lifescience Database Archive (English)

Full Text Available 10380893 Monocyte CD14: a multifunctional receptor engaged in apoptosis from both s...ides. Heidenreich S. J Leukoc Biol. 1999 Jun;65(6):737-43. (.png) (.svg) (.html) (.csml) Show Monocyte CD14: a multifunction...al receptor engaged in apoptosis from both sides. PubmedID 10380893 Title Monocyte CD14: a multifunction

Chemical dampening of Ly6C(hi) monocytes in the periphery produces anti-depressant effects in mice.

Science.gov (United States)

Zheng, Xiao; Ma, Sijing; Kang, An; Wu, Mengqiu; Wang, Lin; Wang, Qiong; Wang, Guangji; Hao, Haiping

2016-01-19

The involvement of systemic immunity in depression pathogenesis promises a periphery-targeting paradigm in novel anti-depressant discovery. However, relatively little is known about druggable targets in the periphery for mental and behavioral control. Here we report that targeting Ly6C(hi) monocytes in blood can serve as a strategy for anti-depressant purpose. A natural compound, ginsenoside Rg1 (Rg1), was firstly validated as a periphery-restricted chemical probe. Rg1 selectively suppressed Ly6C(hi) monocytes recruitment to the inflamed mice brain. The proinflammatory potential of Ly6C(hi) monocytes to activate astrocytes was abrogated by Rg1, which led to a blunted feedback release of CCL2 to recruit the peripheral monocytes. In vitro study demonstrated that Rg1 pretreatment on activated THP-1 monocytes retarded their ability to trigger CCL2 secretion from co-cultured U251 MG astrocytes. CCL2-triggered p38/MAPK and PI3K/Akt activation were involved in the action of Rg1. Importantly, in mice models, we found that dampening Ly6C(hi) monocytes at the periphery ameliorated depression-like behavior induced by neuroinflammation or chronic social defeat stress. Together, our work unravels that blood Ly6C(hi) monocytes may serve as the target to enable remote intervention on the depressed brain, and identifies Rg1 as a lead compound for designing drugs targeting peripheral CCL2 signals.

Hypoxia-induced pulmonary vascular remodeling requires recruitment of circulating mesenchymal precursors of a monocyte/macrophage lineage.

Science.gov (United States)

Frid, Maria G; Brunetti, Jacqueline A; Burke, Danielle L; Carpenter, Todd C; Davie, Neil J; Reeves, John T; Roedersheimer, Mark T; van Rooijen, Nico; Stenmark, Kurt R

2006-02-01

Vascular remodeling in chronic hypoxic pulmonary hypertension includes marked fibroproliferative changes in the pulmonary artery (PA) adventitia. Although resident PA fibroblasts have long been considered the primary contributors to these processes, we tested the hypothesis that hypoxia-induced pulmonary vascular remodeling requires recruitment of circulating mesenchymal precursors of a monocyte/macrophage lineage, termed fibrocytes. Using two neonatal animal models (rats and calves) of chronic hypoxic pulmonary hypertension, we demonstrated a dramatic perivascular accumulation of mononuclear cells of a monocyte/macrophage lineage (expressing CD45, CD11b, CD14, CD68, ED1, ED2). Many of these cells produced type I collagen, expressed alpha-smooth muscle actin, and proliferated, thus exhibiting mesenchymal cell characteristics attributed to fibrocytes. The blood-borne origin of these cells was confirmed in experiments wherein circulating monocytes/macrophages of chronically hypoxic rats were in vivo-labeled with DiI fluorochrome via liposome delivery and subsequently identified in the remodeled pulmonary, but not systemic, arterial adventitia. The DiI-labeled cells that appeared in the vessel wall expressed monocyte/macrophage markers and procollagen. Selective depletion of this monocytic cell population, using either clodronate-liposomes or gadolinium chloride, prevented pulmonary adventitial remodeling (ie, production of collagen, fibronectin, and tenascin-C and accumulation of myofibroblasts). We conclude that circulating mesenchymal precursors of a monocyte/macrophage lineage, including fibrocytes, are essential contributors to hypoxia-induced pulmonary vascular remodeling.

The major surface glycoprotein of Pneumocystis carinii induces release and gene expression of interleukin-8 and tumor necrosis factor alpha in monocytes

DEFF Research Database (Denmark)

Benfield, T L; Lundgren, Bettina; Levine, S J

1997-01-01

Recent studies suggest that interleukin-8 (IL-8) and tumor necrosis factor alpha (TNF-alpha) may play a central role in host defense and pathogenesis during Pneumocystis carinii pneumonia. In order to investigate whether the major surface antigen (MSG) of human P. carinii is capable of eliciting...... the release of IL-8 and TNF-alpha, human monocytes were cultured in the presence of purified MSG. MSG-stimulated cells released significant amounts of IL-8 within 4 h, and at 20 h, cells stimulated with MSG released 45.5 +/- 9.3 ng of IL-8/ml versus 3.7 +/- 1.1 ng/ml for control cultures (P = 0.......01). In a similar fashion, MSG elicited release of TNF-alpha. Initial increases were also seen at 4 h, and at 20 h, TNF-alpha levels reached 6.4 +/- 1.1 ng/ml, compared to 0.08 +/- 0.01 ng/ml for control cultures (P alpha secretion was observed at 20 h...

Anti-CD20 B-cell depletion enhances monocyte reactivity in neuroimmunological disorders

Directory of Open Access Journals (Sweden)

Hohlfeld Reinhard

2011-10-01

Full Text Available Abstract Background Clinical trials evaluating anti-CD20-mediated B-cell depletion in multiple sclerosis (MS and neuromyelitis optica (NMO generated encouraging results. Our recent studies in the MS model experimental autoimmune encephalomyelitis (EAE attributed clinical benefit to extinction of activated B-cells, but cautioned that depletion of naïve B-cells may be undesirable. We elucidated the regulatory role of un-activated B-cells in EAE and investigated whether anti-CD20 may collaterally diminish regulatory B-cell properties in treatment of neuroimmunological disorders. Methods Myelin oligodendrocyte glycoprotein (MOG peptide-immunized C57Bl/6 mice were depleted of B-cells. Functional consequences for regulatory T-cells (Treg and cytokine production of CD11b+ antigen presenting cells (APC were assessed. Peripheral blood mononuclear cells from 22 patients receiving anti-CD20 and 23 untreated neuroimmunological patients were evaluated for frequencies of B-cells, T-cells and monocytes; monocytic reactivity was determined by TNF-production and expression of signalling lymphocytic activation molecule (SLAM. Results We observed that EAE-exacerbation upon depletion of un-activated B-cells closely correlated with an enhanced production of pro-inflammatory TNF by CD11b+ APC. Paralleling this pre-clinical finding, anti-CD20 treatment of human neuroimmunological disorders increased the relative frequency of monocytes and accentuated pro-inflammatory monocyte function; when reactivated ex vivo, a higher frequency of monocytes from B-cell depleted patients produced TNF and expressed the activation marker SLAM. Conclusions These data suggest that in neuroimmunological disorders, pro-inflammatory APC activity is controlled by a subset of B-cells which is eliminated concomitantly upon anti-CD20 treatment. While this observation does not conflict with the general concept of B-cell depletion in human autoimmunity, it implies that its safety and

A high-fat meal promotes lipid-load and apolipoprotein B-48 receptor transcriptional activity in circulating monocytes.

Science.gov (United States)

Varela, Lourdes M; Ortega, Almudena; Bermudez, Beatriz; Lopez, Sergio; Pacheco, Yolanda M; Villar, Jose; Abia, Rocio; Muriana, Francisco J G

2011-05-01

The postprandial metabolism of dietary fats results in the production of apolipoprotein B-48 (apoB48)-containing triglyceride-rich lipoproteins (TRLs), which cause rapid receptor-mediated macrophage lipid engorgement via the apoB48 cell surface receptor (apoB48R). Monocytes circulate together with apoB48-containing TRLs in the postprandial bloodstream and may start accumulating lipids even before their migration to tissues and differentiation to macrophages. We sought to determine whether circulating monocytes are equipped with apoB48R and whether, in the postprandial state, circulating monocytes accumulate lipids and modulate apoB48R transcriptional activity after intake of a high-fat meal. In a crossover design, we studied the effect of a high-fat meal on fasting and postprandial concentrations of triglycerides, free fatty acids, cholesterol, and insulin in 12 healthy men. TRLs and monocytes were freshly isolated at fasting, hourly until the postprandial peak, and at the late postprandial phase. TRLs were subjected to triglycerides, apoB48, and apolipoprotein B-100 analyses; and lipid accumulation and apoB48R mRNA expression levels were measured in monocytes. Monocytes showed a time-dependent lipid accumulation in response to the high-fat meal, which was paralleled by an increase in apoB48R mRNA expression levels. These effects were coincident only with an increase in apoB48-containing TRLs in the postprandial phase and were also observed ex vivo in freshly isolated monocytes incubated with apoB48-containing TRLs. In a setting of abundant plasma apoB48-containing TRLs, these findings highlight the role of dietary fat in inducing lipid accumulation and apoB48R gene transcription in circulating monocytes.

DMPD: Differential responses of human monocytes and macrophages to IL-4 and IL-13. [Dynamic Macrophage Pathway CSML Database

Lifescience Database Archive (English)

Full Text Available 10534111 Differential responses of human monocytes and macrophages to IL-4 and IL-1...):575-8. (.png) (.svg) (.html) (.csml) Show Differential responses of human monocytes and macrophages to IL-...4 and IL-13. PubmedID 10534111 Title Differential responses of human monocytes an

Inhibition of osteoclast differentiation by overexpression of NDRG2 in monocytes

Energy Technology Data Exchange (ETDEWEB)

Kang, Kyeongah; Nam, Sorim; Kim, Bomi; Lim, Ji Hyun; Yang, Young; Lee, Myeong-Sok; Lim, Jong-Seok, E-mail: jslim@sookmyung.ac.kr

2015-12-25

N-Myc downstream-regulated gene 2 (NDRG2), a member of the NDRG family of differentiation-related genes, has been characterized as a regulator of dendritic cell differentiation from monocytes, CD34{sup +} progenitor cells, and myelomonocytic leukemic cells. In this study, we show that NDRG2 overexpression inhibits the differentiation of U937 cells into osteoclasts in response to stimulation with a combination of macrophage colony-stimulating factor (M-CSF) and soluble receptor activator of NF-κB ligand (RANKL). U937 cells stably expressing NDRG2 are unable to differentiate into multinucleated osteoclast-like cells and display reduced tartrate-resistant acid phosphatase (TRAP) activity and resorption pit formation. Furthermore, NDRG2 expression significantly suppresses the expression of genes that are crucial for the proliferation, survival, differentiation, and function of osteoclasts, including c-Fos, Atp6v0d2, RANK, and OSCAR. The activation of ERK1/2 and p38 is also inhibited by NDRG2 expression during osteoclastogenesis, and the inhibition of osteoclastogenesis by NDRG2 correlates with the down-regulation of the expression of the transcription factor PU.1. Taken together, our results suggest that the expression of NDRG2 potentially inhibits osteoclast differentiation and plays a role in modulating the signal transduction pathway responsible for osteoclastogenesis. - Highlights: • The expression of NDRG2 significantly impairs osteoclast differentiation. • PU.1 and p38 MAPK inhibitions by NDRG2 are critical for the inhibition of osteoclastogenesis. • Knockdown of NDRG2 rescues the ability of monocytes to differentiate into osteoclasts. • NDRG2 expression in BM and primary macrophages also impairs osteoclast differentiation. • This study implies the potential of NDRG2 expression in the inhibition of osteoclastogenesis.

The effect of short-chain fatty acids on human monocyte-derived dendritic cells

DEFF Research Database (Denmark)

Nastasi, Claudia; Candela, Marco; Bonefeld, Charlotte Menné

2015-01-01

negligible effects, while both butyrate and propionate strongly modulated gene expression in both immature and mature human monocyte-derived DC. An Ingenuity pathway analysis based on the differentially expressed genes suggested that propionate and butyrate modulate leukocyte trafficking, as SCFA strongly......The gut microbiota is essential for human health and plays an important role in the pathogenesis of several diseases. Short-chain fatty acids (SCFA), such as acetate, butyrate and propionate, are end-products of microbial fermentation of macronutrients that distribute systemically via the blood....... The aim of this study was to investigate the transcriptional response of immature and LPS-matured human monocyte-derived DC to SCFA. Our data revealed distinct effects exerted by each individual SCFA on gene expression in human monocyte-derived DC, especially in the mature ones. Acetate only exerted...

Epigenetic modulators of monocytic function: implication for steady state and disease in the CNS .

Directory of Open Access Journals (Sweden)

F. Nina Papavasiliou

2016-01-01

Full Text Available Epigenetic alterations are necessary for the establishment of functional and phenotypic diversity in populations of immune cells of the monocytic lineage. The epigenetic status of individual genes at different time points defines their transcriptional responses throughout development and in response to environmental stimuli. Epigenetic states are defined at the level of DNA modifications, chromatin modifications, as well as at the level of RNA base changes through RNA editing. Drawing from lessons regarding the epigenome and epitranscriptome of cells of the monocytic lineage in the periphery, and from recently published RNAseq data deriving from brain-resident monocytes, we discuss the impact of modulation of these epigenetic states and how they affect processes important for the development of a healthy brain, as well as mechanisms of neurodegenerative disease and aging. An understanding of the varied brain responses and pathologies in light of these novel gene regulatory systems in monocytes will lead to important new insights in the understanding of the aging process and the treatment and diagnosis of neurodegenerative disease.

Monocytes, neutrophils, and platelets cooperate to initiate and propagate venous thrombosis in mice in vivo

Science.gov (United States)

von Brühl, Marie-Luise; Stark, Konstantin; Steinhart, Alexander; Chandraratne, Sue; Konrad, Ildiko; Lorenz, Michael; Khandoga, Alexander; Tirniceriu, Anca; Coletti, Raffaele; Köllnberger, Maria; Byrne, Robert A.; Laitinen, Iina; Walch, Axel; Brill, Alexander; Pfeiler, Susanne; Manukyan, Davit; Braun, Siegmund; Lange, Philipp; Riegger, Julia; Ware, Jerry; Eckart, Annekathrin; Haidari, Selgai; Rudelius, Martina; Schulz, Christian; Echtler, Katrin; Brinkmann, Volker; Schwaiger, Markus; Preissner, Klaus T.; Wagner, Denisa D.; Mackman, Nigel; Engelmann, Bernd

2012-01-01

Deep vein thrombosis (DVT) is a major cause of cardiovascular death. The sequence of events that promote DVT remains obscure, largely as a result of the lack of an appropriate rodent model. We describe a novel mouse model of DVT which reproduces a frequent trigger and resembles the time course, histological features, and clinical presentation of DVT in humans. We demonstrate by intravital two-photon and epifluorescence microscopy that blood monocytes and neutrophils crawling along and adhering to the venous endothelium provide the initiating stimulus for DVT development. Using conditional mutants and bone marrow chimeras, we show that intravascular activation of the extrinsic pathway of coagulation via tissue factor (TF) derived from myeloid leukocytes causes the extensive intraluminal fibrin formation characteristic of DVT. We demonstrate that thrombus-resident neutrophils are indispensable for subsequent DVT propagation by binding factor XII (FXII) and by supporting its activation through the release of neutrophil extracellular traps (NETs). Correspondingly, neutropenia, genetic ablation of FXII, or disintegration of NETs each confers protection against DVT amplification. Platelets associate with innate immune cells via glycoprotein Ibα and contribute to DVT progression by promoting leukocyte recruitment and stimulating neutrophil-dependent coagulation. Hence, we identified a cross talk between monocytes, neutrophils, and platelets responsible for the initiation and amplification of DVT and for inducing its unique clinical features. PMID:22451716

Modulation of the counts and functions of neutrophils and monocytes under in vivo hyperthermia conditions

DEFF Research Database (Denmark)

Kappel, M; Kharazmi, A; Nielsen, H

1994-01-01

reduced 2 h after hot WI. The total amount (per litre of blood) of superoxide production by PMN stimulated with opsonized zymosan (OZ) was significantly augmented at 39 and 39.5 degrees C and 2 h after WI. In vivo hyperthermia did not affect the function of monocytes, but when correlated to the changes...... in the concentrations of monocytes (response per litre blood) a significant increase in the phorbol myristate acetate (PMA)- and OZ-enhanced superoxide production occurred at 38 and 39 degrees C, as well as 2 h after termination of hot WI. Furthermore the OZ-enhanced monocyte chemiluminescence response per litre...

Monocytes and macrophages in pregnancy and pre-eclampsia

NARCIS (Netherlands)

Faas, Marijke M.; Spaans, Floor; De Vos, Paul

2014-01-01

Preeclampsia is an important complication in pregnancy, characterized by hypertension and proteinuria in the second half of pregnancy. Generalized activation of the inflammatory response is thought to play a role in the pathogenesis of pre-eclampsia. Monocytes may play a central role in this

PU.1 target genes undergo Tet2-coupled demethylation and DNMT3b-mediated methylation in monocyte-to-osteoclast differentiation

DEFF Research Database (Denmark)

de la Rica, Lorenzo; Rodríguez-Ubreva, Javier; García, Mireia

2013-01-01

to osteoclasts is a unique terminal differentiation process within the hematopoietic system. This differentiation model is relevant to autoimmune disease and cancer, and there is abundant knowledge on the sets of transcription factors involved.......DNA methylation is a key epigenetic mechanism for driving and stabilizing cell-fate decisions. Local deposition and removal of DNA methylation are tightly coupled with transcription factor binding, although the relationship varies with the specific differentiation process. Conversion of monocytes...

Treatment of Ebola Virus Infection With a Recombinant Inhibitor of Factor Vlla/Tissue Factor: A Study in Rhesus Monkeys

National Research Council Canada - National Science Library

Geisbert, Thomas W; Hensley, Lisa E; Jahrling, Peter B; Larsen, Tom; Geisbert, Joan B

2003-01-01

Infection with the Ebola virus induces overexpression of the procoagulant tissue factor in primate monocytes and macrophages, suggesting that inhibition of the tissue-factor pathway could ameliorate...

A curated compendium of monocyte transcriptome datasets of relevance to human monocyte immunobiology research [version 2; referees: 2 approved

Directory of Open Access Journals (Sweden)

Darawan Rinchai

2016-04-01

Full Text Available Systems-scale profiling approaches have become widely used in translational research settings. The resulting accumulation of large-scale datasets in public repositories represents a critical opportunity to promote insight and foster knowledge discovery. However, resources that can serve as an interface between biomedical researchers and such vast and heterogeneous dataset collections are needed in order to fulfill this potential. Recently, we have developed an interactive data browsing and visualization web application, the Gene Expression Browser (GXB. This tool can be used to overlay deep molecular phenotyping data with rich contextual information about analytes, samples and studies along with ancillary clinical or immunological profiling data. In this note, we describe a curated compendium of 93 public datasets generated in the context of human monocyte immunological studies, representing a total of 4,516 transcriptome profiles. Datasets were uploaded to an instance of GXB along with study description and sample annotations. Study samples were arranged in different groups. Ranked gene lists were generated based on relevant group comparisons. This resource is publicly available online at http://monocyte.gxbsidra.org/dm3/landing.gsp.

Gastrin-releasing peptide induces monocyte adhesion to vascular endothelium by upregulating endothelial adhesion molecules

International Nuclear Information System (INIS)

Kim, Mi-Kyoung; Park, Hyun-Joo; Kim, Yeon; Kim, Hyung Joon; Bae, Soo-Kyung; Bae, Moon-Kyoung

2017-01-01

Gastrin-releasing peptide (GRP) is a neuropeptide that plays roles in various pathophysiological conditions including inflammatory diseases in peripheral tissues; however, little is known about whether GRP can directly regulate endothelial inflammatory processes. In this study, we showed that GRP promotes the adhesion of leukocytes to human umbilical vein endothelial cells (HUVECs) and the aortic endothelium. GRP increased the expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) by activating nuclear factor-κB (NF-κB) in endothelial cells. In addition, GRP activated extracellular signal-regulated kinase 1/2 (ERK1/2), p38MAPK, and AKT, and the inhibition of these signaling pathways significantly reduced GRP-induced monocyte adhesion to the endothelium. Overall, our results suggested that GRP may cause endothelial dysfunction, which could be of particular relevance in the development of vascular inflammatory disorders. - Highlights: • GRP induces adhesion of monocytes to vascular endothelium. • GRP increases the expression of endothelial adhesion molecules through the activation of NF-κB. • ERK1/2, p38MAPK, and Akt pathways are involved in the GRP-induced leukocyte adhesiveness to endothelium.