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.

Edaravone attenuates monocyte adhesion to endothelial cells induced by oxidized low-density lipoprotein

International Nuclear Information System (INIS)

Li, Zhijuan; Cheng, Jianxin; Wang, Liping

2015-01-01

Oxidized low-density lipoprotein (oxLDL) plays a vital role in recruitment of monocytes to endothelial cells, which is important during early stages of atherosclerosis development. Edaravone, a potent and novel scavenger of free radicals inhibiting hydroxyl radicals, has been clinically used to reduce the neuronal damage following ischemic stroke. In the present study, Edaravone was revealed to markedly reduce oxLDL-induced monocyte adhesion to human umbilical vein endothelial cells (HUVECs). The inhibitory mechanism of Edaravone was associated with suppression of the chemokine MCP-1 and adhesion molecule VCAM-1 and ICAM-1 expression. In addition, luciferase reporter assay results revealed that administration of Edaravone attenuated the increase in NF-κB transcriptional activity induced by oxLDL. Notably, it's also shown that Edaravone treatment blocked oxLDL induced p65 nuclear translocation in HUVECs. Results indicate that Edaravone negatively regulates endothelial inflammation. - Highlights: • Edaravone reduces oxLDL-induced monocyte adhesion to HUVECs. • Edaravone attenuates oxLDL-induced expression of MCP-1, VCAM-1, and ICAM-1. • Edaravone reduces NF-κB transcriptional activity and p65 nuclear translocation.

Protective properties of artichoke (Cynara scolymus) against oxidative stress induced in cultured endothelial cells and monocytes.

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Zapolska-Downar, Danuta; Zapolski-Downar, Andrzej; Naruszewicz, Marek; Siennicka, Aldona; Krasnodebska, Barbara; Kołdziej, Blanka

2002-11-01

It is currently believed that oxidative stress and inflammation play a significant role in atherogenesis. Artichoke extract exhibits hypolipemic properties and contains numerous active substances with antioxidant properties in vitro. We have studied the influence of aqueous and ethanolic extracts from artichoke on intracellular oxidative stress stimulated by inflammatory mediators (TNFalpha and LPS) and ox-LDL in endothelial cells and monocytes. Oxidative stress which reflects the intracellular production of reactive oxygen species (ROS) was followed by measuring the oxidation of 2', 7'-dichlorofluorescin (DCFH) to 2', 7'-dichlorofluorescein (DCF). Agueous and ethanolic extracts from artichoke were found to inhibit basal and stimulated ROS production in endothelial cells and monocytes in dose dependent manner. In endothelial cells, the ethanolic extract (50 microg/ml) reduced ox-LDL-induced intracellular ROS production by 60% (partichoke extracts have marked protective properties against oxidative stress induced by inflammatory mediators and ox-LDL in cultured endothelial cells and monocytes.

Edaravone attenuates monocyte adhesion to endothelial cells induced by oxidized low-density lipoprotein

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Li, Zhijuan, E-mail: zjlee038@163.com; Cheng, Jianxin; Wang, Liping

2015-10-30

Oxidized low-density lipoprotein (oxLDL) plays a vital role in recruitment of monocytes to endothelial cells, which is important during early stages of atherosclerosis development. Edaravone, a potent and novel scavenger of free radicals inhibiting hydroxyl radicals, has been clinically used to reduce the neuronal damage following ischemic stroke. In the present study, Edaravone was revealed to markedly reduce oxLDL-induced monocyte adhesion to human umbilical vein endothelial cells (HUVECs). The inhibitory mechanism of Edaravone was associated with suppression of the chemokine MCP-1 and adhesion molecule VCAM-1 and ICAM-1 expression. In addition, luciferase reporter assay results revealed that administration of Edaravone attenuated the increase in NF-κB transcriptional activity induced by oxLDL. Notably, it's also shown that Edaravone treatment blocked oxLDL induced p65 nuclear translocation in HUVECs. Results indicate that Edaravone negatively regulates endothelial inflammation. - Highlights: • Edaravone reduces oxLDL-induced monocyte adhesion to HUVECs. • Edaravone attenuates oxLDL-induced expression of MCP-1, VCAM-1, and ICAM-1. • Edaravone reduces NF-κB transcriptional activity and p65 nuclear translocation.

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.

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

Edaravone attenuates monocyte adhesion to endothelial cells induced by oxidized low-density lipoprotein.

Science.gov (United States)

Li, Zhijuan; Cheng, Jianxin; Wang, Liping

2015-10-30

Oxidized low-density lipoprotein (oxLDL) plays a vital role in recruitment of monocytes to endothelial cells, which is important during early stages of atherosclerosis development. Edaravone, a potent and novel scavenger of free radicals inhibiting hydroxyl radicals, has been clinically used to reduce the neuronal damage following ischemic stroke. In the present study, Edaravone was revealed to markedly reduce oxLDL-induced monocyte adhesion to human umbilical vein endothelial cells (HUVECs). The inhibitory mechanism of Edaravone was associated with suppression of the chemokine MCP-1 and adhesion molecule VCAM-1 and ICAM-1 expression. In addition, luciferase reporter assay results revealed that administration of Edaravone attenuated the increase in NF-κB transcriptional activity induced by oxLDL. Notably, it's also shown that Edaravone treatment blocked oxLDL induced p65 nuclear translocation in HUVECs. Results indicate that Edaravone negatively regulates endothelial inflammation. Copyright © 2015. Published by Elsevier Inc.

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.

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.

HLA class I antibodies trigger increased adherence of monocytes to endothelial cells by eliciting an increase in endothelial P-selectin and, depending on subclass, by engaging FcγRs.

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Valenzuela, Nicole M; Mulder, Arend; Reed, Elaine F

2013-06-15

Ab-mediated rejection (AMR) of solid organ transplants is characterized by intragraft macrophages. It is incompletely understood how donor-specific Ab binding to graft endothelium promotes monocyte adhesion, and what, if any, contribution is made by the Fc region of the Ab. We investigated the mechanisms underlying monocyte recruitment by HLA class I (HLA I) Ab-activated endothelium. We used a panel of murine mAbs of different subclasses to crosslink HLA I on human aortic, venous, and microvascular endothelial cells and measured the binding of human monocytic cell lines and peripheral blood monocytes. Both anti-HLA I murine (m)IgG1 and mIgG2a induced endothelial P-selectin, which was required for monocyte adhesion to endothelium irrespective of subclass. mIgG2a but not mIgG1 could bind human FcγRs. Accordingly, HLA I mIgG2a but not mIgG1 treatment of endothelial cells significantly augmented recruitment, predominantly through FcγRI, and, to a lesser extent, FcγRIIa. Moreover, HLA I mIgG2a promoted firm adhesion of monocytes to ICAM-1 through Mac-1, which may explain the prominence of monocytes during AMR. We confirmed these observations using human HLA allele-specific mAbs and IgG purified from transplant patient sera. HLA I Abs universally elicit endothelial exocytosis leading to monocyte adherence, implying that P-selectin is a putative therapeutic target to prevent macrophage infiltration during AMR. Importantly, the subclass of donor-specific Ab may influence its pathogenesis. These results imply that human IgG1 and human IgG3 should have a greater capacity to trigger monocyte infiltration into the graft than IgG2 or IgG4 due to enhancement by FcγR interactions.

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.

PGC-1-related coactivator (PRC) negatively regulates endothelial adhesion of monocytes via inhibition of NF κB activity

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Chengye, Zhan; Daixing, Zhou, E-mail: dxzhou7246@hotmail.com; Qiang, Zhong; Shusheng, Li

2013-09-13

Highlights: •First time to display that LPS downregulate the expression of PRC. •First time to show that PRC inhibits the induction of VCAM-1 and E-selectin. •First time to show that PRC inhibit monocytes attachment to endothelial cells. •First time to display that PRC inhibits transcriptional activity of NF-κB. •PRC protects the respiration rate and suppresses the glycolysis rate against LPS. -- Abstract: PGC-1-related coactivator (PRC) is a growth-regulated transcriptional cofactor known to activate many of the nuclear genes specifying mitochondrial respiratory function. Endothelial dysfunction is a prominent feature found in many inflammatory diseases. Adhesion molecules, such as VCAM-1, mediate the attachment of monocytes to endothelial cells, thereby playing an important role in endothelial inflammation. The effects of PRC in regards to endothelial inflammation remain unknown. In this study, our findings show that PRC can be inhibited by the inflammatory cytokine LPS in cultured human umbilical vein endothelial cells (HUVECs). In the presence of LPS, the expression of endothelial cell adhesion molecular, such as VCAM1 and E-selectin, is found to be increased. These effects can be negated by overexpression of PRC. Importantly, monocyte adhesion to endothelial cells caused by LPS is significantly attenuated by PRC. In addition, overexpression of PRC protects mitochondrial metabolic function and suppresses the rate of glycolysis against LPS. It is also found that overexpression of PRC decreases the transcriptional activity of NF-κB. These findings suggest that PRC is a negative regulator of endothelial inflammation.

Cerebrospinal fluid monocyte chemoattractant protein-1 in alcoholics: support for a neuroinflammatory model of chronic alcoholism.

Science.gov (United States)

Umhau, John C; Schwandt, Melanie; Solomon, Matthew G; Yuan, Peixiong; Nugent, Allison; Zarate, Carlos A; Drevets, Wayne C; Hall, Samuel D; George, David T; Heilig, Markus

2014-05-01

Liver inflammation in alcoholism has been hypothesized to influence the development of a neuroinflammatory process in the brain characterized by neurodegeneration and altered cognitive function. Monocyte chemoattractant protein-1/chemokine (C-C motif) ligand 2 (MCP-1/CCL2) elevations have been noted in the alcoholic brain at autopsy and may have a role in this process. We studied cerebrospinal fluid (CSF) levels of MCP-1 as well as interleukin-1β and tumor necrosis factor-α in 13 healthy volunteers and 28 alcoholics during weeks 1 and 4 following detoxification. Serum liver enzymes were obtained as markers of alcohol-related liver inflammation. Compared to healthy volunteers, MCP-1 levels were significantly higher in alcoholics both on day 4 and day 25 (p alcohol-induced liver inflammation, as defined by peripheral concentrations of GGT and AST/GOT. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.

HLA class I antibodies trigger increased adherence of monocytes to endothelial cells by eliciting an increase in endothelial P-selectin and, depending on subclass, by engaging FcγRs1

Science.gov (United States)

Valenzuela, Nicole M; Mulder, Arend; Reed, Elaine F

2013-01-01

Antibody-mediated rejection of solid organ transplants is characterized by intragraft macrophages. It is incompletely understood how donor specific antibody binding to graft endothelium promotes monocyte adhesion, and what, if any, contribution is made by the Fc region of the antibody. We investigated the mechanisms underlying monocyte recruitment by HLA class I antibody-activated endothelium. We used a panel of murine monoclonal antibodies of different subclasses to crosslink HLA I on human aortic, venous and microvascular endothelial cells, and measured the binding of human monocytic cell lines and peripheral blood monocytes. Both anti-HLA I murine IgG1 and mIgG2a induced endothelial P-selectin, which was required for monocyte adhesion to endothelium irrespective of subclass. Mouse IgG2a but not mIgG1 could bind human FcγRs. Accordingly, HLA I mIgG2a but not mIgG1 treatment of endothelial cells significantly augmented recruitment, predominantly through FcγRI, and, to a lesser extent, FcγRIIa. Moreover, HLA I mIgG2a promoted firm adhesion of monocytes to ICAM-1 through Mac-1, which may explain the prominence of monocytes during antibody mediated rejection. We confirmed these observations using human HLA allele specific monoclonal antibodies and IgG purified from transplant patient sera. HLA I antibodies universally elicit endothelial exocytosis leading to monocyte adherence, implying that P-selectin is a putative therapeutic target to prevent macrophage infiltration during antibody-mediated rejection. Importantly, the subclass of donor specific antibody may influence its pathogenesis. These results imply that hIgG1 and hIgG3 should have a greater capacity to trigger monocyte infiltration into the graft than IgG2 or IgG4 due to enhancement by FcγR interactions. PMID:23690477

Suppression of lipin-1 expression increases monocyte chemoattractant protein-1 expression in 3T3-L1 adipocytes

International Nuclear Information System (INIS)

Takahashi, Nobuhiko; Yoshizaki, Takayuki; Hiranaka, Natsumi; Suzuki, Takeshi; Yui, Tomoo; Akanuma, Masayasu; Oka, Kazuya; Kanazawa, Kaoru; Yoshida, Mika; Naito, Sumiyoshi; Fujiya, Mikihiro; Kohgo, Yutaka; Ieko, Masahiro

2011-01-01

Highlights: ► Lipin-1 affects lipid metabolism, adipocyte differentiation, and transcription. ► Adipose lipin-1 expression is reduced in obesity. ► Lipin-1 depletion using siRNA in 3T3-L1 adipocytes increased MCP-1 expression. ► Lipin-1 is involved in adipose inflammation. -- Abstract: Lipin-1 plays a crucial role in the regulation of lipid metabolism and cell differentiation in adipocytes. Expression of adipose lipin-1 is reduced in obesity, and metabolic syndrome. However, the significance of this reduction remains unclear. This study investigated if and how reduced lipin-1 expression affected metabolism. We assessed mRNA expression levels of various genes related to adipocyte metabolism in lipin-1-depleted 3T3-L1 adipocytes by introducing its specific small interfering RNA. In lipin-1-depleted adipocytes, mRNA and protein expression levels of monocyte chemoattractant protein-1 (MCP-1) were significantly increased, although the other genes tested were not altered. The conditioned media from the cells promoted monocyte chemotaxis. The increase in MCP-1 expression was prevented by treatment with quinazoline or salicylate, inhibitors of nuclear factor-κB activation. Because MCP-1 is related to adipose inflammation and systemic insulin resistance, these results suggest that a reduction in adipose lipin-1 in obesity may exacerbate adipose inflammation and metabolism.

Suppression of lipin-1 expression increases monocyte chemoattractant protein-1 expression in 3T3-L1 adipocytes

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Takahashi, Nobuhiko, E-mail: ntkhs@hoku-iryo-u.ac.jp [Department of Internal Medicine, School of Dentistry, Health Sciences University of Hokkaido, 1757 Kanazawa, Ishikari-Toubetsu, Hokkaido 061-0023 (Japan); Division of Gastroenterology and Hematology/Oncology, Department of Medicine, Asahikawa Medical University, 2-1-1-1 Midorigaoka-Higashi, Asahikawa, Hokkaido 078-8510 (Japan); Yoshizaki, Takayuki [Innovation Center, Kagoshima University, 1-21-40 Korimoto, Kagoshima 890-0065 (Japan); Hiranaka, Natsumi; Suzuki, Takeshi [Department of Internal Medicine, School of Dentistry, Health Sciences University of Hokkaido, 1757 Kanazawa, Ishikari-Toubetsu, Hokkaido 061-0023 (Japan); Yui, Tomoo; Akanuma, Masayasu; Oka, Kazuya [Department of Fixed Prosthodontics and Oral Implantology, School of Dentistry, Health Sciences University of Hokkaido, 1757 Kanazawa, Ishikari-Toubetsu, Hokkaido 061-0023 (Japan); Kanazawa, Kaoru [Department of Dental Anesthesiology, School of Dentistry, Health Sciences University of Hokkaido, 1757 Kanazawa, Ishikari-Toubetsu, Hokkaido 061-0023 (Japan); Yoshida, Mika; Naito, Sumiyoshi [Department of Clinical Laboratory, Health Sciences University of Hokkaido, 1757 Kanazawa, Ishikari-Toubetsu, Hokkaido 061-0023 (Japan); Fujiya, Mikihiro; Kohgo, Yutaka [Division of Gastroenterology and Hematology/Oncology, Department of Medicine, Asahikawa Medical University, 2-1-1-1 Midorigaoka-Higashi, Asahikawa, Hokkaido 078-8510 (Japan); Ieko, Masahiro [Department of Internal Medicine, School of Dentistry, Health Sciences University of Hokkaido, 1757 Kanazawa, Ishikari-Toubetsu, Hokkaido 061-0023 (Japan)

2011-11-11

Highlights: Black-Right-Pointing-Pointer Lipin-1 affects lipid metabolism, adipocyte differentiation, and transcription. Black-Right-Pointing-Pointer Adipose lipin-1 expression is reduced in obesity. Black-Right-Pointing-Pointer Lipin-1 depletion using siRNA in 3T3-L1 adipocytes increased MCP-1 expression. Black-Right-Pointing-Pointer Lipin-1 is involved in adipose inflammation. -- Abstract: Lipin-1 plays a crucial role in the regulation of lipid metabolism and cell differentiation in adipocytes. Expression of adipose lipin-1 is reduced in obesity, and metabolic syndrome. However, the significance of this reduction remains unclear. This study investigated if and how reduced lipin-1 expression affected metabolism. We assessed mRNA expression levels of various genes related to adipocyte metabolism in lipin-1-depleted 3T3-L1 adipocytes by introducing its specific small interfering RNA. In lipin-1-depleted adipocytes, mRNA and protein expression levels of monocyte chemoattractant protein-1 (MCP-1) were significantly increased, although the other genes tested were not altered. The conditioned media from the cells promoted monocyte chemotaxis. The increase in MCP-1 expression was prevented by treatment with quinazoline or salicylate, inhibitors of nuclear factor-{kappa}B activation. Because MCP-1 is related to adipose inflammation and systemic insulin resistance, these results suggest that a reduction in adipose lipin-1 in obesity may exacerbate adipose inflammation and metabolism.

Complement-Mediated Enhancement of Monocyte Adhesion to Endothelial Cells by HLA Antibodies, and Blockade by a Specific Inhibitor of the Classical Complement Cascade, TNT003

Science.gov (United States)

Valenzuela, Nicole M.; Thomas, Kimberly A.; Mulder, Arend; Parry, Graham C.; Panicker, Sandip; Reed, Elaine F.

2017-01-01

Background Antibody-mediated rejection (AMR) of most solid organs is characterized by evidence of complement activation and/or intragraft macrophages (C4d + and CD68+ biopsies). We previously demonstrated that crosslinking of HLA I by antibodies triggered endothelial activation and monocyte adhesion. We hypothesized that activation of the classical complement pathway at the endothelial cell surface by HLA antibodies would enhance monocyte adhesion through soluble split product generation, in parallel with direct endothelial activation downstream of HLA signaling. Methods Primary human aortic endothelial cells (HAEC) were stimulated with HLA class I antibodies in the presence of intact human serum complement. C3a and C5a generation, endothelial P-selectin expression, and adhesion of human primary and immortalized monocytes (Mono Mac 6) were measured. Alternatively, HAEC or monocytes were directly stimulated with purified C3a or C5a. Classical complement activation was inhibited by pretreatment of complement with an anti-C1s antibody (TNT003). Results Treatment of HAEC with HLA antibody and human complement increased the formation of C3a and C5a. Monocyte recruitment by human HLA antibodies was enhanced in the presence of intact human serum complement or purified C3a or C5a. Specific inhibition of the classical complement pathway using TNT003 or C1q-depleted serum significantly reduced adhesion of monocytes in the presence of human complement. Conclusions Despite persistent endothelial viability in the presence of HLA antibodies and complement, upstream complement anaphylatoxin production exacerbates endothelial exocytosis and leukocyte recruitment. Upstream inhibition of classical complement may be therapeutic to dampen mononuclear cell recruitment and endothelial activation characteristic of microvascular inflammation during AMR. PMID:28640789

Monoclonal antibody OKM5 inhibits the in vitro binding of Plasmodium falciparum-infected erythrocytes to monocytes, endothelial, and C32 melanoma cells

International Nuclear Information System (INIS)

Barnwell, J.W.; Ockenhouse, C.F.; Knowles, D.M. II

1985-01-01

Plasmodium falciparum-infected erythrocytes bind in vitro to human endothelial cells, monocytes, and a certain melanoma cell line. Evidence suggests that this interaction is mediated by similar mechanisms which lead to the sequestration of parasitized erythrocytes in vivo through their attachment to endothelial cells of small blood vessels. They show here the monoclonal antibody OKM5, previously shown to react with the membranes of endothelial cells, monocyte,s and platelets, also reacts with the C32 melanoma cell line which also binds P. falciparum-infected erythrocytes. At relatively low concentrations, OKM5 inhibits and reverses the in vitro adherence of infected erythrocytes to target cells. As with monocytes, OKM5 antibody recognizes an 125 I-labeled protein of approximately 88 Kd on the surface of C32 melanoma cells. It seems likely, therefore, that the 88 Kd polypeptide plays a role in cytoadherence, possibly as the receptor or part of a receptor for a ligand on the surface of infected erythrocytes

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.

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.

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

Energy Technology Data Exchange (ETDEWEB)

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.

Identification of a Monocyte Receptor on Herpesvirus-Infected Endothelial Cells

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Etingin, Orli R.; Silverstein, Roy L.; Hajjar, David P.

1991-08-01

The adhesion of circulating blood cells to vascular endothelium may be an initial step in atherosclerosis, inflammation, and wound healing. One mechanism for promoting cell-cell adhesion involves the expression of adhesion molecules on the surface of the target cell. Herpes simplex virus infection of endothelium induces arterial injury and has been implicated in the development of human atherosclerosis. We now demonstrate that HSV-infected endothelial cells express the adhesion molecule GMP140 and that this requires cell surface expression of HSV glycoprotein C and local thrombin generation. Monocyte adhesion to HSV-infected endothelial cells was completely inhibited by anti-GMP140 antibodies but not by antibodies to other adhesion molecules such as VCAM and ELAM-1. The induction of GMP140 expression on HSV-infected endothelium may be an important pathophysiological mechanism in virus-induced cell injury and inflammation.

Monocyte chemoattractant protein 1, intercellular adhesion molecule 1, and vascular cell adhesion molecule 1 in exudative age-related macular degeneration.

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Jonas, Jost B; Tao, Yong; Neumaier, Michael; Findeisen, Peter

2010-10-01

To examine intraocular concentrations of monocyte chemoattractant protein 1 (MCP-1), soluble intercellular adhesion molecule 1 (sICAM-1), soluble vascular cell adhesion molecule 1 (sVCAM-1), and vascular endothelial growth factor (VEGF) in eyes with exudative age-related macular degeneration (AMD). The investigation included a study group of 28 patients (28 eyes) with exudative AMD and a control group of 25 patients (25 eyes) with cataract. The concentrations of MCP-1, sICAM-1, sVCAM-1, and VEGF in aqueous humor samples obtained during surgery were measured using a solid-phase chemiluminescence immunoassay. The study group as compared with the control group had higher aqueous concentrations of sICAM-1 (mean [SD], 844 [2073] vs 246 [206] pg/mL, respectively; P < .001), sVCAM-1 (mean [SD], 7978 [7120] vs 2999 [1426] pg/mL, respectively; P < .001), and MCP-1 (mean [SD], 587 [338] vs 435 [221] pg/mL, respectively; P = .07). The concentration of VEGF did not vary significantly between the groups (P = .76). The MCP-1 concentration was significantly associated with macular thickness (r = 0.40; P = .004). It decreased significantly with the type of subfoveal neovascular membrane (classic membrane type, occult membrane, retinal pigment epithelium detachment) (P = .009). The concentrations of sICAM-1, sVCAM-1, and VEGF were not significantly associated with membrane type and macular thickness (P ≥ .18). Concentrations of MCP-1, sICAM-1, and sVCAM-1 are significantly associated with exudative AMD, even in the presence of normal VEGF concentrations. Intraocular MCP-1 concentrations are correlated with the subfoveal neovascular membrane type and the amount of macular edema. One may infer that MCP-1, sICAM-1, and sVCAM-1 could potentially be additional target molecules in therapy for exudative AMD.

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

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.

Systems Biology Reveals Cigarette Smoke-Induced Concentration-Dependent Direct and Indirect Mechanisms That Promote Monocyte-Endothelial Cell Adhesion.

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Poussin, Carine; Laurent, Alexandra; Peitsch, Manuel C; Hoeng, Julia; De Leon, Hector

2015-10-01

Cigarette smoke (CS) affects the adhesion of monocytes to endothelial cells, a critical step in atherogenesis. Using an in vitro adhesion assay together with innovative computational systems biology approaches to analyze omics data, our study aimed at investigating CS-induced mechanisms by which monocyte-endothelial cell adhesion is promoted. Primary human coronary artery endothelial cells (HCAECs) were treated for 4 h with (1) conditioned media of human monocytic Mono Mac-6 (MM6) cells preincubated with low or high concentrations of aqueous CS extract (sbPBS) from reference cigarette 3R4F for 2 h (indirect treatment, I), (2) unconditioned media similarly prepared without MM6 cells (direct treatment, D), or (3) freshly generated sbPBS (fresh direct treatment, FD). sbPBS promoted MM6 cells-HCAECs adhesion following I and FD, but not D. In I, the effect was mediated at a low concentration through activation of vascular inflammation processes promoted in HCAECs by a paracrine effect of the soluble mediators secreted by sbPBS-treated MM6 cells. Tumor necrosis factor α (TNFα), a major inducer, was actually shed by unstable CS compound-activated TNFα-converting enzyme. In FD, the effect was triggered at a high concentration that also induced some toxicity. This effect was mediated through an yet unknown mechanism associated with a stress damage response promoted in HCAECs by unstable CS compounds present in freshly generated sbPBS, which had decayed in D unconditioned media. Aqueous CS extract directly and indirectly promotes monocytic cell-endothelial cell adhesion in vitro via distinct concentration-dependent mechanisms. © The Author 2015. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Outside-in HLA class I signaling regulates ICAM-1 clustering and endothelial cell-monocyte interactions via mTOR in transplant antibody-mediated rejection.

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Salehi, Sahar; Sosa, Rebecca A; Jin, Yi-Ping; Kageyama, Shoichi; Fishbein, Michael C; Rozengurt, Enrique; Kupiec-Weglinski, Jerzy W; Reed, Elaine F

2018-05-01

Antibody-mediated rejection (AMR) resulting in transplant allograft vasculopathy (TAV) is the major obstacle for long-term survival of solid organ transplants. AMR is caused by donor-specific antibodies to HLA, which contribute to TAV by initiating outside-in signaling transduction pathways that elicit monocyte recruitment to activated endothelium. Mechanistic target of rapamycin (mTOR) inhibitors can attenuate TAV; therefore, we sought to understand the mechanistic underpinnings of mTOR signaling in HLA class I Ab-mediated endothelial cell activation and monocyte recruitment. We used an in vitro model to assess monocyte binding to HLA I Ab-activated endothelial cells and found mTOR inhibition reduced ezrin/radixin/moesin (ERM) phosphorylation, intercellular adhesion molecule 1 (ICAM-1) clustering, and monocyte firm adhesion to HLA I Ab-activated endothelium. Further, in a mouse model of AMR, in which C57BL/6. RAG1 -/- recipients of BALB/c cardiac allografts were passively transferred with donor-specific MHC I antibodies, mTOR inhibition significantly reduced vascular injury, ERM phosphorylation, and macrophage infiltration of the allograft. Taken together, these studies indicate mTOR inhibition suppresses ERM phosphorylation in endothelial cells, which impedes ICAM-1 clustering in response to HLA class I Ab and prevents macrophage infiltration into cardiac allografts. These findings indicate a novel therapeutic application for mTOR inhibitors to disrupt endothelial cell-monocyte interactions during AMR. © 2017 The American Society of Transplantation and the American Society of Transplant Surgeons.

Chondroitin Sulfate Inhibits Monocyte Chemoattractant Protein-1 Release From 3T3-L1 Adipocytes: A New Treatment Opportunity for Obesity-Related Inflammation?

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Thomas V Stabler

2017-08-01

Full Text Available Monocyte chemoattractant protein-1 (MCP-1 overproduction from inflamed adipose tissue is a major contributor to obesity-related metabolic syndromes. 3T3-L1 embryonic fibroblasts were cultured and differentiated into adipocytes using an established protocol. Adipocytes were treated with lipopolysaccharide (LPS to induce inflammation and thus MCP-1 release. At the same time, varying concentrations of chondroitin sulfate (CS were added in a physiologically relevant range (10-200 µg/mL to determine its impact on MCP-1 release. Chondroitin sulfate, a natural glycosaminoglycan of connective tissue including the cartilage extracellular matrix, was chosen on the basis of our previous studies demonstrating its anti-inflammatory effect on macrophages. Because the main action of MCP-1 is to induce monocyte migration, cultured THP-1 monocytes were used to test whether CS at the highest physiologically relevant concentration could inhibit cell migration induced by human recombinant MCP-1. Chondroitin sulfate (100-200 µg/mL inhibited MCP-1 release from inflamed adipocytes in a dose-dependent manner ( P  < .01, 95% confidence interval [CI]: −5.89 to −3.858 at 100 µg/mL and P  < .001, 95% CI: −6.028 to −3.996 at 200 µg/mL but had no effect on MCP-1–driven chemotaxis of THP-1 monocytes. In summary, CS could be expected to reduce macrophage infiltration into adipose tissue by reduction in adipocyte expression and release of MCP-1 and as such might reduce adipose tissue inflammation in response to pro-inflammatory stimuli such as LPS, now increasingly recognized to be relevant in vivo.

Indirect induction of endothelial cell injury by PU- or PTFE-mediated activation of monocytes.

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Liu, Xin; Xue, Yang; Sun, Jiao

2010-01-01

Polyurethanes (PUs) and polytetrafluoroethylene (PTFE) are widely used for making cardiovascular devices, but thrombus formation on the surfaces of these devices is inevitable. Since endothelial injury can lead to thrombosis, most of the studies on PUs or PTFE focused on their damage to endothelial cells. However, few studies have attempted to clarify whether the use of foreign objects as biomaterials can cause endothelial injury by activating the innate immune system. In this study, we aimed to investigate the roles of PU- or PTFE-stimulated immune cells in endothelial-cell injury. First, monocytes (THP-1 cells) were stimulated with PU or PTFE for 24 h and, subsequently, human umbilical vein endothelial cells (HUVECs) were treated with the supernatants of the stimulated cells for 24 h. We measured the generation of intracellular reactive oxygen species (ROS) from THP-1 cells treated with PU and PTFE for 24 h, meanwhile hydrogen dioxide (H(2)O(2)), tumor necrosis factor (TNF)-α and interleukin (IL)-1β in the supernatants were also detected. Then, we assessed the apoptosis rate of the HUVECs and determined the expression of NO, inducible nitric oxide synthase (iNOS), and apoptosis-related proteins (p53, Bax, Bcl-2) in the HUVECs. The results showed that large amounts of ROS and low levels of pro-inflammatory cytokines (TNF-α and IL-1β) were produced by the stimulated THP-1 cells. After culturing with the supernatants of the PU- or PTFE-stimulated THP-1 cells, the apoptosis rate, NO production and expression of iNOS, p53 and Bax in the HUVECs were up-regulated, while Bcl-2 expression was down-regulated. In conclusion, the release of ROS by PU- or PTFE-treated THP-1 cells may induce iNOS expression and cause apoptosis in HUVECs via the p53, Bax and Bcl-2 proteins. These data provide the interesting finding that endothelial injury in the process of biomaterial-induced thrombosis can be initiated through the release of soluble mediators by monocytes.

Palmitate-induced inflammatory pathways in human adipose microvascular endothelial cells promote monocyte adhesion and impair insulin transcytosis.

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Pillon, Nicolas J; Azizi, Paymon M; Li, Yujin E; Liu, Jun; Wang, Changsen; Chan, Kenny L; Hopperton, Kathryn E; Bazinet, Richard P; Heit, Bryan; Bilan, Philip J; Lee, Warren L; Klip, Amira

2015-07-01

Obesity is associated with inflammation and immune cell recruitment to adipose tissue, muscle and intima of atherosclerotic blood vessels. Obesity and hyperlipidemia are also associated with tissue insulin resistance and can compromise insulin delivery to muscle. The muscle/fat microvascular endothelium mediates insulin delivery and facilitates monocyte transmigration, yet its contribution to the consequences of hyperlipidemia is poorly understood. Using primary endothelial cells from human adipose tissue microvasculature (HAMEC), we investigated the effects of physiological levels of fatty acids on endothelial inflammation and function. Expression of cytokines and adhesion molecules was measured by RT-qPCR. Signaling pathways were evaluated by pharmacological manipulation and immunoblotting. Surface expression of adhesion molecules was determined by immunohistochemistry. THP1 monocyte interaction with HAMEC was measured by cell adhesion and migration across transwells. Insulin transcytosis was measured by total internal reflection fluorescence microscopy. Palmitate, but not palmitoleate, elevated the expression of IL-6, IL-8, TLR2 (Toll-like receptor 2), and intercellular adhesion molecule 1 (ICAM-1). HAMEC had markedly low fatty acid uptake and oxidation, and CD36 inhibition did not reverse the palmitate-induced expression of adhesion molecules, suggesting that inflammation did not arise from palmitate uptake/metabolism. Instead, inhibition of TLR4 to NF-κB signaling blunted palmitate-induced ICAM-1 expression. Importantly, palmitate-induced surface expression of ICAM-1 promoted monocyte binding and transmigration. Conversely, palmitate reduced insulin transcytosis, an effect reversed by TLR4 inhibition. In summary, palmitate activates inflammatory pathways in primary microvascular endothelial cells, impairing insulin transport and increasing monocyte transmigration. This behavior may contribute in vivo to reduced tissue insulin action and enhanced tissue

Importance of large conductance calcium-activated potassium channels (BKCa) in interleukin-1b-induced adhesion of monocytes to endothelial cells.

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Burgazli, K M; Venker, C J; Mericliler, M; Atmaca, N; Parahuleva, M; Erdogan, A

2014-01-01

The present study investigated the role of the large conductance calcium-activated potassium channels (BKCa) in interleukin-1b (IL-1b) induced inflammation. Human umbilical vein endothelial cells (HUVECs) were isolated and cultured. Endothelial cell membrane potential measurements were accomplished using the fluorescent dye DiBAC4(3). The role of BKCa was assessed using iberiotoxin, a highly selective BKCa inhibitor. Changes in the calcium intracellular calcium were investigated using Fura-2-AM imaging. Fluorescent dyes DCF-AM and DAF-AM were further used in order to measure the formation of reactive oxygen species (ROS) and nitric oxide (NO) synthesis, respectively. Endothelial cell adhesion tests were conducted with BCECF-AM adhesion assay and tritium thymidine uptake using human monocytic cells (U937). Expression of cellular adhesion molecules (ICAM-1, VCAM-1) was determined by flow cytometer. Interleukin-1b induced a BKCa dependent hyperpolarization of HUVECs. This was followed by an increase in the intracellular calcium concentration. Furthermore, IL-1b significantly increased the synthesis of NO and ROS. The increase of intracellular calcium, radicals and NO resulted in a BKCa dependent adhesion of monocytes to HUVECs. Endothelial cells treated with IL-1b expressed both ICAM-1 and VCAM-1 in significantly higher amounts as when compared to controls. It was further shown that the cellular adhesion molecules ICAM-1 and VCAM-1 were responsible for the BKCa-dependent increase in cellular adhesion. Additionally, inhibition of the NADPH oxidase with DPI led to a significant downregulation of IL-1b-induced expression of ICAM and VCAM, as well as inhibition of eNOS by L-NMMA, and intracellular calcium by BAPTA. Activation of the endothelial BKCa plays an important role in the IL-1b-induced monocyte adhesion to endothelial cells.

Plasma cytokines eotaxin, MIP-1α, MCP-4, and vascular endothelial growth factor in acute lower respiratory tract infection

DEFF Research Database (Denmark)

Relster, Mette Marie; Holm, Anette; Pedersen, Court

2017-01-01

), monocyte chemoattractant protein 4 (MCP-4), and vascular endothelial growth factor (VEGF) in 40 patients hospitalized with acute lower respiratory tract infections (LRTI). The cytokines contribute to the pathogenesis of several inflammatory respiratory diseases, indicating a potential as markers for LRTI....... Patients were stratified according to etiology and severity of LRTI, based on baseline C-reactive protein and CURB-65 scores. Using a multiplex immunoassay of plasma, levels of eotaxin and MCP-4 were shown to increase from baseline until day 6 after admission to hospital. The four cytokines were unable...

Anti-inflammatory evaluation of the methanolic extract of Taraxacum officinale in LPS-stimulated human umbilical vein endothelial cells.

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Jeon, Daun; Kim, Seok Joong; Kim, Hong Seok

2017-11-29

Atherosclerosis is a chronic vascular inflammatory disease. Since even low-level endotoxemia constitutes a powerful and independent risk factor for the development of atherosclerosis, it is important to find therapies directed against the vascular effects of endotoxin to prevent atherosclerosis. Taraxacum officinale (TO) is used for medicinal purposes because of its choleretic, diuretic, antioxidative, anti-inflammatory, and anti-carcinogenic properties, but its anti-inflammatory effect on endothelial cells has not been established. We evaluated the anti-inflammatory activity of TO filtered methanol extracts in LPS-stimulated human umbilical vein endothelial cells (HUVECs) by monocyte adhesion and western blot assays. HUVECs were pretreated with 100 μg/ml TO for 1 h and then incubated with 1 μg/ml LPS for 24 h. The mRNA and protein expression levels of the targets (pro-inflammatory cytokines and adhesion molecules) were analyzed by real-time PCR and western blot assays. We also preformed HPLC analysis to identify the components of the TO methanol extract. The TO filtered methanol extracts dramatically inhibited LPS-induced endothelial cell-monocyte interactions by reducing vascular cell adhesion molecule-1 and monocyte chemoattractant protein-1, and pro-inflammatory cytokine expression. TO suppressed the LPS-induced nuclear translocation of NF-κB, whereas it did not affect MAPK activation. Our findings demonstrated that methanol extracts of TO could attenuate LPS-induced endothelial cell activation by inhibiting the NF-κB pathway. These results indicate the potential clinical benefits and applications of TO for the prevention of vascular inflammation and atherosclerosis.

Plasma Monocyte Chemoattractant Protein-1 Level as a Predictor of the Severity of Community-Acquired Pneumonia

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Kok-Khun Yong

2016-01-01

Full Text Available Monocyte chemoattractant protein (MCP-1 increases in the serum of immunocompetent patients with community-acquired pneumonia (CAP. However, the correlation between the circulating level of MCP-1 and severity of CAP remains unclear. This study investigated differential changes in the plasma MCP-1 levels of patients with CAP before and after an antibiotic treatment and further analyzes the association between the CAP severity and MCP-1 levels. We measured the plasma MCP-1 levels of 137 patients with CAP and 74 healthy controls by using a commercial enzyme-linked immunosorbent assay. Upon initial hospitalization, Acute Physiology and Chronic Health Evaluation II (APACHE II; confusion, urea level, respiratory rate, blood pressure, and age of >64 years (CURB-65; and pneumonia severity index (PSI scores were determined for assessing the CAP severity in these patients. The antibiotic treatment reduced the number of white blood cells (WBCs and neutrophils as well as the level of C-reactive protein (CRP and MCP-1. The plasma MCP-1 level, but not the CRP level or WBC count, correlated with the CAP severity according to the PSI (r = 0.509, p < 0.001, CURB-65 (r = 0.468, p < 0.001, and APACHE II (r = 0.360, p < 0.001 scores. We concluded that MCP-1 levels act in the development of CAP and are involved in the severity of CAP.

Monocyte chemoattractant protein-1: a proinflammatory cytokine elevated in sarcopenic obesity

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Lim JP

2015-03-01

Full Text Available Jun Pei Lim,1,2 Bernard P Leung,3 Yew Yoong Ding,1,2 Laura Tay,1,2 Noor Hafizah Ismail,2,4 Audrey Yeo,2 Suzanne Yew,2 Mei Sian Chong1,2 1Department of Geriatric Medicine, 2Institute of Geriatrics and Active Ageing, 3Department of Rheumatology, Allergy and Immunology, 4Department of Community and Continuing Care, Tan Tock Seng Hospital, Singapore Objective: Sarcopenic obesity (SO is associated with poorer physical outcomes and functional status in the older adult. A proinflammatory milieu associated with central obesity is postulated to enhance muscle catabolism. We set out to examine associations of the chemokine monocyte chemoattractant protein-1 (MCP-1 in groups of older adults, with sarcopenia, obesity, and the SO phenotypes.Methods: A total of 143 community dwelling, well, older adults were recruited. Cross-sectional clinical data, physical performance, and muscle mass measurements were collected. Obesity and sarcopenia were defined using revised National Cholesterol Education Program (NCEP obesity guidelines and those of the Asian Working Group for Sarcopenia. Serum levels of MCP-1 were measured by enzyme-linked immunosorbent assay (ELISA.Results: In all, 25.2% of subjects were normal, 15.4% sarcopenic, 48.3% obese, and 11.2% were SO. The SO groups had the lowest appendicular lean mass, highest percentage body fat, and lowest performance scores on the Short Physical Performance Battery and grip strength. The MCP-1 levels were significantly different, with the highest levels found in SO participants (P<0.05.Conclusion: Significantly raised MCP-1 levels in obese and SO subjects support the theory of chronic inflammation due to excess adiposity. Longitudinal studies will reveal whether SO represents a continuum of obesity causing accelerated sarcopenia and cardiovascular events, or the coexistence of two separate conditions with synergistic effects affecting functional performance. Keywords: chemokine C-C motif ligand 2 (CCL-2, elderly

Leonurine protects against tumor necrosis factor-α-mediated inflammation in human umbilical vein endothelial cells.

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Liu, Xinhua; Pan, Lilong; Wang, Xianli; Gong, Qihai; Zhu, Yi Zhun

2012-05-01

Leonurine, a bioactive alkaloid compound in Herba leonuri, has various pharmacological activities, including antioxidant and anti-apoptotic capacities. This study was conducted to test the hypothesis that leonurine was able to attenuate tumor necrosis factor (TNF)-α-induced human umbilical vein endothelial cells (HUVEC) activation and the underlying molecular mechanisms. Mitogen-activated protein kinases (MAPK) activation, nuclear factor-κB (NF-κB) activation, and inflammatory mediators expression were detected by Western blot or enzyme-liked immunosorbent assay, intracellular reactive oxygen species (ROS) and NF-κB p65 translocation were measured by immunofluorescence, endothelial cell-monocyte interaction was detected by microscope. Leonurine inhibited U937 cells adhesion to TNF-α-activated HUVEC in a concentration dependent manner. Treatment with leonurine blocked TNF-α-induced mRNA and protein expression of adhesion molecules (intercellular adhesion molecule-1 and vascular cell adhesion molecule-1), cyclooxygenase-2, and monocyte chemoattractant protein-1 in endothelial cells. In addition, leonurine attenuated TNF-α-induced intracellular ROS production in HUVEC. Furthermore, leonurine also suppressed the TNF-α-activated p38 phosphorylation and IκBα degradation. Subsequently, reduced NF-κB p65 phosphorylation, nuclear translocation, and DNA-binding activity were also observed. Our results demonstrated for the first time that the anti-inflammatory properties of leonurine in endothelial cells, at least in part, through suppression of NF-κB activation, which may have a potential therapeutic use for inflammatory vascular diseases. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

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.

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.

Multiple anti-inflammatory and anti-atherosclerotic properties of red wine polyphenolic extracts: differential role of hydroxycinnamic acids, flavonols and stilbenes on endothelial inflammatory gene expression.

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Calabriso, Nadia; Scoditti, Egeria; Massaro, Marika; Pellegrino, Mariangela; Storelli, Carlo; Ingrosso, Ilaria; Giovinazzo, Giovanna; Carluccio, Maria Annunziata

2016-03-01

The aim of the study was to evaluate the vascular anti-inflammatory effects of polyphenolic extracts from two typical South Italy red wines, the specific contribution of individual polyphenols and the underlying mechanisms of action. Human endothelial cells were incubated with increasing concentrations (1-50 μg/mL) of Primitivo and Negroamaro polyphenolic extracts (PWPE and NWPE, respectively) or pure polyphenols (1-25 μmol/L), including hydroxycinnamic acids (p-coumaric, caffeic and caftaric acids), flavonols (kaempferol, quercetin, myricetin) or stilbenes (trans-resveratrol, trans-piceid) before stimulation with lipopolysaccharide. Through multiple assays, we analyzed the endothelial-monocyte adhesion, the endothelial expression of adhesion molecules (ICAM-1, VCAM-1 and E-Selectin), monocyte chemoattractant protein-1 (MCP-1) and macrophage colony-stimulating factor (M-CSF), as well as ROS intracellular levels and the activation of NF-κB and AP-1. Both PWPE and NWPE, already at 1 μg/mL, inhibited monocyte adhesion to stimulated endothelial cells, a key event in triggering vascular inflammation. They down-regulated the expression of adhesion molecules, ICAM-1, VCAM-1, E-Selectin, as well as MCP-1 and M-CSF, at mRNA and protein levels. All polyphenols reduced intracellular ROS, and everything, except caftaric acid, inhibited the endothelial expression of adhesion molecules and MCP-1, although with different potency. Flavonols and resveratrol significantly reduced also the endothelial expression and release of M-CSF. The decrease in endothelial inflammatory gene expression was related to the inhibition of NF-κB and AP-1 activation but not to intracellular oxidative stress. This study showed multiple anti-inflammatory and anti-atherosclerotic properties of red wine polyphenolic extracts and indentified specific bioactive polyphenols which could counteract inflammatory diseases including atherosclerosis.

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.

Androgen-androgen receptor system improves chronic inflammatory conditions by suppressing monocyte chemoattractant protein-1 gene expression in adipocytes via transcriptional regulation

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Morooka, Nobukatsu, E-mail: amorooka@gunma-u.ac.jp [Institute for Molecular and Cellular Regulation, Gunma University, 3-39-15 Showa-machi, Maebashi, Gunma, 371-8512 (Japan); Ueguri, Kei [Institute for Molecular and Cellular Regulation, Gunma University, 3-39-15 Showa-machi, Maebashi, Gunma, 371-8512 (Japan); Yee, Karen Kar Lye [Institute for Molecular and Cellular Regulation, Gunma University, 3-39-15 Showa-machi, Maebashi, Gunma, 371-8512 (Japan); Human Resources Cultivation Center, Gunma University, 1-5-1 Tenjin-cho, Kiryushi, Gunma, 376-8515 (Japan); Yanase, Toshihiko [Department of Endocrinology and Diabetes Mellitus, School of Medicine, Fukuoka University, Jonan-ku, Fukuoka, 814-0180 (Japan); Sato, Takashi [Institute for Molecular and Cellular Regulation, Gunma University, 3-39-15 Showa-machi, Maebashi, Gunma, 371-8512 (Japan)

2016-09-02

Age-related decreases in sex hormones are closely related to chronic inflammation in obesity and metabolic diseases. Particularly, the molecular basis of androgen activity in regulating inflammation and controlling metabolism remains largely unknown. Obese adipocytes secrete monocyte chemoattractant protein-1 (MCP-1), a key chemokine that promotes the infiltration of monocytes/macrophages into adipose tissue, thereby leading to metabolic disorders. Here, we studied the role of androgen-androgen receptor (AR) action in regulating MCP-1 expression in adipose tissue. We observed the induction of Mcp-1 expression in 3T3-L1 adipocytes co-cultured with RAW264.7 macrophages. Additionally, Mcp-1 expression was upregulated by culturing in conditioned medium derived from inflammatory macrophages (M1-Mφ) containing tumor necrosis factor-alpha (TNF-α). We found that sex hormones downregulated TNF-α-induced Mcp-1 and interleukin (Il)-6 expression in 3T3-L1 adipocytes. Furthermore, luciferase-reporter analysis indicated that MCP-1 promoter activity was predominantly suppressed by dihydrotestosterone (DHT)-AR interactions through functional canonical nuclear factor-kappa B (NF-κB) sites, whereas non-canonical NF-κB site containing important flanking sequences exhibited minor contributions to DHT-AR transcriptional repression. These findings suggested that androgen-AR suppressed obesity-induced chronic inflammation in adipose tissue. - Highlights: • DHT, non-aromatizable androgen suppresses Mcp-1 expression in adipocytes. • Mcp-1 transcription was negatively regulated by DHT-AR action. • DHT-AR selectively regulates Mcp-1 transcription through distinct NF-κB sites.

Androgen-androgen receptor system improves chronic inflammatory conditions by suppressing monocyte chemoattractant protein-1 gene expression in adipocytes via transcriptional regulation

International Nuclear Information System (INIS)

Morooka, Nobukatsu; Ueguri, Kei; Yee, Karen Kar Lye; Yanase, Toshihiko; Sato, Takashi

2016-01-01

Age-related decreases in sex hormones are closely related to chronic inflammation in obesity and metabolic diseases. Particularly, the molecular basis of androgen activity in regulating inflammation and controlling metabolism remains largely unknown. Obese adipocytes secrete monocyte chemoattractant protein-1 (MCP-1), a key chemokine that promotes the infiltration of monocytes/macrophages into adipose tissue, thereby leading to metabolic disorders. Here, we studied the role of androgen-androgen receptor (AR) action in regulating MCP-1 expression in adipose tissue. We observed the induction of Mcp-1 expression in 3T3-L1 adipocytes co-cultured with RAW264.7 macrophages. Additionally, Mcp-1 expression was upregulated by culturing in conditioned medium derived from inflammatory macrophages (M1-Mφ) containing tumor necrosis factor-alpha (TNF-α). We found that sex hormones downregulated TNF-α-induced Mcp-1 and interleukin (Il)-6 expression in 3T3-L1 adipocytes. Furthermore, luciferase-reporter analysis indicated that MCP-1 promoter activity was predominantly suppressed by dihydrotestosterone (DHT)-AR interactions through functional canonical nuclear factor-kappa B (NF-κB) sites, whereas non-canonical NF-κB site containing important flanking sequences exhibited minor contributions to DHT-AR transcriptional repression. These findings suggested that androgen-AR suppressed obesity-induced chronic inflammation in adipose tissue. - Highlights: • DHT, non-aromatizable androgen suppresses Mcp-1 expression in adipocytes. • Mcp-1 transcription was negatively regulated by DHT-AR action. • DHT-AR selectively regulates Mcp-1 transcription through distinct NF-κB sites.

The role and mechanism of KCa3.1 channels in human monocyte migration induced by palmitic acid.

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Ma, Xiao-Zhen; Pang, Zheng-Da; Wang, Jun-Hong; Song, Zheng; Zhao, Li-Mei; Du, Xiao-Jun; Deng, Xiu-Ling

2018-05-21

Monocyte migration into diseased tissues contributes to the pathogenesis of diseases. Intermediate-conductance Ca 2+ -activated K + (K Ca 3.1) channels play an important role in cell migration. However, the role of K Ca 3.1 channels in mediating monocyte migration induced by palmitic acid (PA) is still unclear. Using cultured THP-1 cells and peripheral blood mononuclear cells from healthy subjects, we investigated the role and signaling mechanisms of K Ca 3.1 channels in mediating the migration induced by PA. Using methods of Western blotting analysis, RNA interference, cell migration assay and ELISA, we found that PA-treated monocytes exhibited increment of the protein levels of K Ca 3.1 channel and monocyte chemoattractant protein-1 (MCP-1), and the effects were reversed by co-incubation of PA with anti-TLR2/4 antibodies or by specific inhibitors of p38-MAPK, or NF-κB. In addition, PA increased monocyte migration, which was abolished by a specific K Ca 3.1 channel blocker, TRAM-34, or K Ca 3.1 small interfering RNA (siRNA). The expression and secretion of MCP-1 induced by PA was also similarly prevented by TRAM-34 and K Ca 3.1 siRNA. These results demonstrate for the first time that PA upregulates K Ca 3.1 channels through TLR2/4, p38-MAPK and NF-κB pathway to promote the expression of MCP-1, and then induce the trans-endothelial migration of monocytes. Copyright © 2018 Elsevier Inc. All rights reserved.

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.

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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.

A hot water extract of Curcuma longa inhibits adhesion molecule protein expression and monocyte adhesion to TNF-α-stimulated human endothelial cells.

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Kawasaki, Kengo; Muroyama, Koutarou; Yamamoto, Norio; Murosaki, Shinji

2015-01-01

The recruitment of arterial leukocytes to endothelial cells is an important step in the progression of various inflammatory diseases. Therefore, its modulation is thought to be a prospective target for the prevention or treatment of such diseases. Adhesion molecules on endothelial cells are induced by proinflammatory cytokines, including tumor necrosis factor-α (TNF-α), and contribute to the recruitment of leukocytes. In the present study, we investigated the effect of hot water extract of Curcuma longa (WEC) on the protein expression of adhesion molecules, monocyte adhesion induced by TNF-α in human umbilical vascular endothelial cells (HUVECs). Treatment of HUVECs with WEC significantly suppressed both TNF-α-induced protein expression of adhesion molecules and monocyte adhesion. WEC also suppressed phosphorylation and degradation of nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, alpha (IκBα) induced by TNF-α in HUVECs, suggesting that WEC inhibits the NF-κB signaling pathway.

Influence of HFE variants and cellular iron on monocyte chemoattractant protein-1

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Simmons Zachary

2009-02-01

Full Text Available Abstract Background Polymorphisms in the MHC class 1-like gene known as HFE have been proposed as genetic modifiers of neurodegenerative diseases that include neuroinflammation as part of the disease process. Variants of HFE are relatively common in the general population and are most commonly associated with iron overload, but can promote subclinical cellular iron loading even in the absence of clinically identified disease. The effects of the variants as well as the resulting cellular iron dyshomeostasis potentially impact a number of disease-associated pathways. We tested the hypothesis that the two most common HFE variants, H63D and C282Y, would affect cellular secretion of cytokines and trophic factors. Methods We screened a panel of cytokines and trophic factors using a multiplexed immunoassay in human neuroblastoma SH-SY5Y cells expressing different variants of HFE. The influence of cellular iron secretion on the potent chemokine monocyte chemoattractant protein-1 (MCP-1 was assessed using ferric ammonium citrate and the iron chelator, desferroxamine. Additionally, an antioxidant, Trolox, and an anti-inflammatory, minocycline, were tested for their effects on MCP-1 secretion in the presence of HFE variants. Results Expression of the HFE variants altered the labile iron pool in SH-SY5Y cells. Of the panel of cytokines and trophic factors analyzed, only the release of MCP-1 was affected by the HFE variants. We further examined the relationship between iron and MCP-1 and found MCP-1 secretion tightly associated with intracellular iron status. A potential direct effect of HFE is considered because, despite having similar levels of intracellular iron, the association between HFE genotype and MCP-1 expression was different for the H63D and C282Y HFE variants. Moreover, HFE genotype was a factor in the effect of minocycline, a multifaceted antibiotic used in treating a number of neurologic conditions associated with inflammation, on MCP-1

Mesenchymal Stem/Multipotent Stromal Cells from Human Decidua Basalis Reduce Endothelial Cell Activation.

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Alshabibi, Manal A; Al Huqail, Al Joharah; Khatlani, Tanvir; Abomaray, Fawaz M; Alaskar, Ahmed S; Alawad, Abdullah O; Kalionis, Bill; Abumaree, Mohamed Hassan

2017-09-15

Recently, we reported the isolation and characterization of mesenchymal stem cells from the decidua basalis of human placenta (DBMSCs). These cells express a unique combination of molecules involved in many important cellular functions, which make them good candidates for cell-based therapies. The endothelium is a highly specialized, metabolically active interface between blood and the underlying tissues. Inflammatory factors stimulate the endothelium to undergo a change to a proinflammatory and procoagulant state (ie, endothelial cell activation). An initial response to endothelial cell activation is monocyte adhesion. Activation typically involves increased proliferation and enhanced expression of adhesion and inflammatory markers by endothelial cells. Sustained endothelial cell activation leads to a type of damage to the body associated with inflammatory diseases, such as atherosclerosis. In this study, we examined the ability of DBMSCs to protect endothelial cells from activation through monocyte adhesion, by modulating endothelial proliferation, migration, adhesion, and inflammatory marker expression. Endothelial cells were cocultured with DBMSCs, monocytes, monocyte-pretreated with DBMSCs and DBMSC-pretreated with monocytes were also evaluated. Monocyte adhesion to endothelial cells was examined following treatment with DBMSCs. Expression of endothelial cell adhesion and inflammatory markers was also analyzed. The interaction between DBMSCs and monocytes reduced endothelial cell proliferation and monocyte adhesion to endothelial cells. In contrast, endothelial cell migration increased in response to DBMSCs and monocytes. Endothelial cell expression of adhesion and inflammatory molecules was reduced by DBMSCs and DBMSC-pretreated with monocytes. The mechanism of reduced endothelial proliferation involved enhanced phosphorylation of the tumor suppressor protein p53. Our study shows for the first time that DBMSCs protect endothelial cells from activation by

Induced migration of endothelial cells into 3D scaffolds by chemoattractants secreted by pro-inflammatory macrophages in situ.

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Li, Xuguang; Dai, Yuankun; Shen, Tao; Gao, Changyou

2017-06-01

Cell migration in scaffolds plays a crucial role in tissue regeneration, which can better mimic cell behaviors in vivo . In this study, a novel model has been proposed on controlling 3D cell migration in porous collagen-chitosan scaffolds with various pore structures under the stimulation of inflammatory cells to mimic the angiogenesis process. Endothelial cells (ECs) cultured atop the scaffolds in the Transwell molds which were placed into a well of a 24-well culture plate were promoted to migrate into the scaffolds by chemoattractants such as vascular endothelial growth factor (VEGF) and tumor necrosis factor-alpha (TNF-α) secreted by the pro-inflammatory macrophages incubated in the well culture plate. The phenotype of macrophages was mediated by 50 ng/ml interferon-gamma (IFN-γ) and different concentrations of lipopolysaccharide (LPS, 150-300 ng/ml). The cell migration depth had a positive correlation with LPS concentration, and thereby the TNF-α concentration. The ECs migrated easier to a deeper zone of the scaffolds prepared at - 10ºC (187 μm in pore diameter) than that at - 20ºC (108 μm in pore diameter) as well. The method provides a useful strategy to study the 3D cell migration, and is helpful to reveal the vascularization process during wound healing in the long run.

Complement 5a Enhances Hepatic Metastases of Colon Cancer via Monocyte Chemoattractant Protein-1-mediated Inflammatory Cell Infiltration*

Science.gov (United States)

Piao, Chunmei; Cai, Lun; Qiu, Shulan; Jia, Lixin; Song, Wenchao; Du, Jie

2015-01-01

Complement 5a (C5a), a potent immune mediator generated by complement activation, promotes tumor growth; however, its role in tumor metastasis remains unclear. We demonstrate that C5a contributes to tumor metastases by modulating tumor inflammation in hepatic metastases of colon cancer. Colon cancer cell lines generate C5a under serum-free conditions, and C5a levels increase over time in a murine syngeneic colon cancer hepatic metastasis model. Furthermore, in the absence of C5a receptor or upon pharmacological inhibition of C5a production with an anti-C5 monoclonal antibody, tumor metastasis is severely impaired. A lack of C5a receptor in colon cancer metastatic foci reduces the infiltration of macrophages, neutrophils, and dendritic cells, and the role for C5a receptor on these cells were further verified by bone marrow transplantation experiments. Moreover, C5a signaling increases the expression of the chemokine monocyte chemoattractant protein-1 and the anti-inflammatory molecules arginase-1, interleukin 10, and transforming growth factor β, but is inversely correlated with the expression of pro-inflammatory molecules, which suggests a mechanism for the role of C5a in the inflammatory microenvironment required for tumor metastasis. Our results indicate a new and potentially promising therapeutic application of complement C5a inhibitor for the treatment of malignant tumors. PMID:25739439

Adiponectin, interleukin-6, monocyte chemoattractant protein-1, and regional fat mass during 12-month randomized treatment with metformin and/or oral contraceptives in polycystic ovary syndrome

DEFF Research Database (Denmark)

Glintborg, Dorte; Mumm, Hanne; Altinok, Magda Lambaa

2014-01-01

CONTEXT: Central obesity in polycystic ovary syndrome (PCOS) is associated with increased inflammatory markers and increased risk for type 2 diabetes. OBJECTIVE: To evaluate if improved body composition during treatment with metformin (M) vs. oral contraceptive pills (OCP) was associated...... with changes in circulating adiponectin, interleukin (IL)-6, and monocyte chemoattractant protein (MCP)-1. PATIENTS AND INTERVENTIONS: Ninety patients with PCOS were randomized to 12-month treatment with M (2 g/day), M + OCP (150 mg desogestrel + 30 microgram ethinylestradiol) or OCP. Adiponectin, IL-6, MCP-1...... during the three types of medical intervention. Treatment with M and M + OCP was superior to OCP regarding decreased regional fat mass. Baseline adiponectin and IL-6 were associated with BMI, waist, and trunk fat mass. Changes in trunk fat were significantly associated with changes in IL-6 and MCP-1...

Monocyte function is severely impaired by the fluorochrome calcein acetomethylester

International Nuclear Information System (INIS)

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

Inhibitory effects of Kaempferia parviflora extract on monocyte adhesion and cellular reactive oxygen species production in human umbilical vein endothelial cells.

Science.gov (United States)

Horigome, Satoru; Yoshida, Izumi; Ito, Shihomi; Inohana, Shuichi; Fushimi, Kei; Nagai, Takeshi; Yamaguchi, Akihiro; Fujita, Kazuhiro; Satoyama, Toshiya; Katsuda, Shin-Ichi; Suzuki, Shinobu; Watai, Masatoshi; Hirose, Naoto; Mitsue, Takahiro; Shirakawa, Hitoshi; Komai, Michio

2017-04-01

The rhizome of Kaempferia parviflora (KP) is used in traditional Thai medicine. In this study, we investigated the effects of an ethanol KP extract and two of its components [5,7-dimethoxyflavone (DMF) and 5-hydroxy-3,7,3',4'-tetramethoxyflavone (TMF)] on monocyte adhesion and cellular reactive oxygen species (ROS) production in human umbilical vein endothelial cells (HUVECs), which provide an in vitro model of events relevant to the development and progression of atherosclerosis. RAW264.7 mouse macrophage-like cells were incubated with various concentrations of KP extract or polymethoxyflavonoids and stimulated with lipopolysaccharide prior to measuring nitrite levels in the culture media. Monocyte adhesion was evaluated by measuring the fluorescently labeled human monocytic leukemia THP-1 cells that is attached to tumor necrosis factor-α (TNF-α)-stimulated HUVECs. Cellular ROS production was assessed by measuring cellular antioxidant activity using pyocyanin-stimulated HUVECs. KP extract and DMF reduced nitrite levels (as indicator of nitric oxide production) in LPS-stimulated RAW264.7 cells and also inhibited THP-1 cell adhesion to HUVECs. These treatments induced mRNA expression of endothelial nitric oxide synthase in TNF-α-stimulated HUVECs and downregulated that of various cell adhesion molecules, inflammatory mediators, and endothelial function-related genes. Angiotensin-converting enzyme activity was inhibited by KP extract in vitro. Furthermore, KP extract, DMF, and TMF inhibited the production of cellular ROS in pyocyanin-stimulated HUVECs. KP extract, DMF, and TMF showed potential anti-inflammatory and antioxidant effects in these in vitro models, properties that would inhibit the development and progression of atherosclerosis.

Expression of adhesion molecules, monocyte interactions and oxidative stress in human endothelial cells exposed to wood smoke and diesel exhaust particulate matter

DEFF Research Database (Denmark)

Forchhammer, Lykke; Loft, Steffen; Roursgaard, Martin

2012-01-01

Toxicological effects of wood smoke particles are less investigated than traffic-related combustion particles. We investigated the effect of wood smoke particles, generated by smouldering combustion conditions, on human umbilical endothelial cells (HUVECs) co-cultured with or without monocytic TH...

Loss of monocyte chemoattractant protein-1 alters macrophage polarization and reduces NFκB activation in the foreign body response.

Science.gov (United States)

Moore, Laura Beth; Sawyer, Andrew J; Charokopos, Antonios; Skokos, Eleni A; Kyriakides, Themis R

2015-01-01

Implantation of biomaterials elicits a foreign body response characterized by fusion of macrophages to form foreign body giant cells and fibrotic encapsulation. Studies of the macrophage polarization involved in this response have suggested that alternative (M2) activation is associated with more favorable outcomes. Here we investigated this process in vivo by implanting mixed cellulose ester filters or polydimethylsiloxane disks in the peritoneal cavity of wild-type (WT) and monocyte chemoattractant protein-1 (MCP-1) knockout mice. We analyzed classical (M1) and alternative (M2) gene expression via quantitative polymerase chain reaction, immunohistochemistry and enzyme-linked immunosorbent assay in both non-adherent cells isolated by lavage and implant-adherent cells. Our results show that macrophages undergo unique activation that displays features of both M1 and M2 polarization including induction of tumor necrosis factor α (TNF), which induces the expression and nuclear translocation of p50 and RelA determined by immunofluorescence and Western blot. Both processes were compromised in fusion-deficient MCP-1 KO macrophages in vitro and in vivo. Furthermore, inclusion of BAY 11-7028, an inhibitor of NFκB activation, reduced nuclear translocation of RelA and fusion in WT macrophages. Our studies suggest that peritoneal implants elicit a unique macrophage polarization phenotype leading to induction of TNF and activation of the NFκB pathway. Published by Elsevier Ltd.

Complement 5a Enhances Hepatic Metastases of Colon Cancer via Monocyte Chemoattractant Protein-1-mediated Inflammatory Cell Infiltration.

Science.gov (United States)

Piao, Chunmei; Cai, Lun; Qiu, Shulan; Jia, Lixin; Song, Wenchao; Du, Jie

2015-04-24

Complement 5a (C5a), a potent immune mediator generated by complement activation, promotes tumor growth; however, its role in tumor metastasis remains unclear. We demonstrate that C5a contributes to tumor metastases by modulating tumor inflammation in hepatic metastases of colon cancer. Colon cancer cell lines generate C5a under serum-free conditions, and C5a levels increase over time in a murine syngeneic colon cancer hepatic metastasis model. Furthermore, in the absence of C5a receptor or upon pharmacological inhibition of C5a production with an anti-C5 monoclonal antibody, tumor metastasis is severely impaired. A lack of C5a receptor in colon cancer metastatic foci reduces the infiltration of macrophages, neutrophils, and dendritic cells, and the role for C5a receptor on these cells were further verified by bone marrow transplantation experiments. Moreover, C5a signaling increases the expression of the chemokine monocyte chemoattractant protein-1 and the anti-inflammatory molecules arginase-1, interleukin 10, and transforming growth factor β, but is inversely correlated with the expression of pro-inflammatory molecules, which suggests a mechanism for the role of C5a in the inflammatory microenvironment required for tumor metastasis. Our results indicate a new and potentially promising therapeutic application of complement C5a inhibitor for the treatment of malignant tumors. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

Endothelial-monocyte activating polypeptide II alters fibronectin based endothelial cell adhesion and matrix assembly via alpha5 beta1 integrin

International Nuclear Information System (INIS)

Schwarz, Margaret A.; Zheng, Hiahua; Liu, Jie; Corbett, Siobhan; Schwarz, Roderich E.

2005-01-01

Mature Endothelial-Monocyte Activating Polypeptide (mEMAP) II functions as a potent antiangiogenic peptide. Although the anti-tumor effect of mEMAP II has been described, little is known regarding its mechanism of action. Observations that mEMAP II induced apoptosis only in a subset of migrating and proliferating endothelial cells (EC) suggests a targeted effect on cells engaged in angiogenic activities which are known to rely upon cell adhesion and migration. Indeed, we demonstrate that mEMAP II inhibited fibronectin (FN) dependent microvascular EC (MEC) adhesion and spreading and we show that this depends upon the alpha5 beta1 integrin. Immunofluorescence analysis demonstrated that mEMAP II-dependent blockade of FN-alpha5 beta1 interactions was associated with disassembly of both actin stress fiber networks and FN matrix. These findings suggest that mEMAP II blocks MEC adhesion and spreading on fibronectin, via a direct interaction with the integrin alpha5 beta1, thus implicating that alpha5 integrin may be a mediator of mEMAP II's antiangiogenic function

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

Energy Technology Data Exchange (ETDEWEB)

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.

Thioredoxin reductase 1 upregulates MCP-1 release in human endothelial cells

Energy Technology Data Exchange (ETDEWEB)

Liu, Zhen-Bo [Institute of Biophysics, Chinese Academy of Sciences, and Graduate School of the Chinese Academy of Sciences, Beijing (China); Shen, Xun, E-mail: shenxun@sun5.ibp.ac.cn [Institute of Biophysics, Chinese Academy of Sciences, and Graduate School of the Chinese Academy of Sciences, Beijing (China)

2009-09-04

To know if thioredoxin reductase 1 (TrxR1) plays a role in antioxidant defense mechanisms against atherosclerosis, effect of TrxR1 on expression/release of monocyte chemoattractant protein (MCP-1) was investigated in activated human endothelial-like EAhy926 cells. The MCP-1 release and expression, cellular generation of reactive oxygen species (ROS), nuclear translocation and DNA-binding activity of NF-{kappa}B subunit p65 were assayed in cells either overexpressing recombinant TrxR1 or having their endogenous TrxR1 knocked down. It was found that overexpression of TrxR1 enhanced, while knockdown of TrxR1 reduced MCP-1 release and expression. Upregulation of MCP-1 by TrxR1 was associated with increasing generation of intracellular ROS generation, enhanced nuclear translocation and DNA-binding activity of NF-{kappa}B. Assay using NF-{kappa}B reporter revealed that TrxR1 upregulated transcriptional activity of NF-{kappa}B. This study suggests that TrxR1 enhances ROS generation, NF-{kappa}B activity and subsequent MCP-1 expression in endothelial cells, and may promote rather than prevent vascular endothelium from forming atherosclerotic plaque.

Cell proliferation and migration are modulated by Cdk-1-phosphorylated endothelial-monocyte activating polypeptide II.

Directory of Open Access Journals (Sweden)

Margaret A Schwarz

Full Text Available Endothelial-Monocyte Activating Polypeptide (EMAP II is a secreted protein with well-established anti-angiogenic activities. Intracellular EMAP II expression is increased during fetal development at epithelial/mesenchymal boundaries and in pathophysiologic fibroproliferative cells of bronchopulmonary dysplasia, emphysema, and scar fibroblast tissue following myocardial ischemia. Precise function and regulation of intracellular EMAP II, however, has not been explored to date.Here we show that high intracellular EMAP II suppresses cellular proliferation by slowing progression through the G2M cell cycle transition in epithelium and fibroblast. Furthermore, EMAP II binds to and is phosphorylated by Cdk1, and exhibits nuclear/cytoplasmic partitioning, with only nuclear EMAP II being phosphorylated. We observed that extracellular secreted EMAP II induces endothelial cell apoptosis, where as excess intracellular EMAP II facilitates epithelial and fibroblast cells migration.Our findings suggest that EMAP II has specific intracellular effects, and that this intracellular function appears to antagonize its extracellular anti-angiogenic effects during fetal development and pulmonary disease progression.

The adaptor CRADD/RAIDD controls activation of endothelial cells by proinflammatory stimuli.

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Qiao, Huan; Liu, Yan; Veach, Ruth A; Wylezinski, Lukasz; Hawiger, Jacek

2014-08-08

A hallmark of inflammation, increased vascular permeability, is induced in endothelial cells by multiple agonists through stimulus-coupled assembly of the CARMA3 signalosome, which contains the adaptor protein BCL10. Previously, we reported that BCL10 in immune cells is targeted by the "death" adaptor CRADD/RAIDD (CRADD), which negatively regulates nuclear factor κB (NFκB)-dependent cytokine and chemokine expression in T cells (Lin, Q., Liu, Y., Moore, D. J., Elizer, S. K., Veach, R. A., Hawiger, J., and Ruley, H. E. (2012) J. Immunol. 188, 2493-2497). This novel anti-inflammatory CRADD-BCL10 axis prompted us to analyze CRADD expression and its potential anti-inflammatory action in non-immune cells. We focused our study on microvascular endothelial cells because they play a key role in inflammation. We found that CRADD-deficient murine endothelial cells display heightened BCL10-mediated expression of the pleotropic proinflammatory cytokine IL-6 and chemokine monocyte chemoattractant protein-1 (MCP-1/CCL2) in response to LPS and thrombin. Moreover, these agonists also induce significantly increased permeability in cradd(-/-), as compared with cradd(+/+), primary murine endothelial cells. CRADD-deficient cells displayed more F-actin polymerization with concomitant disruption of adherens junctions. In turn, increasing intracellular CRADD by delivery of a novel recombinant cell-penetrating CRADD protein (CP-CRADD) restored endothelial barrier function and suppressed the induction of IL-6 and MCP-1 evoked by LPS and thrombin. Likewise, CP-CRADD enhanced barrier function in CRADD-sufficient endothelial cells. These results indicate that depletion of endogenous CRADD compromises endothelial barrier function in response to inflammatory signals. Thus, we define a novel function for CRADD in endothelial cells as an inducible suppressor of BCL10, a key mediator of responses to proinflammatory agonists. © 2014 by The American Society for Biochemistry and Molecular Biology

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...

Strenuous physical exercise adversely affects monocyte chemotaxis

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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...

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

[Role of phosphoinositide 3 kinase/protein kinase B signal pathway in monocyte-endothelial adhesion induced by serum of rats with electrical burn].

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Ruan, Qiongfang; Zhao, Chaoli; Ye, Ziqing; Zhang, Weidong; Xie, Qionghui; Xie, Weiguo

2014-06-01

To observe the change in phosphoinositide 3-kinase/protein kinase B (PI3K/Akt) signal pathway in monocytes as induced by serum of rats with electrical burn, and to explore the effects of PI3K/Akt pathway on monocyte-endothelial cell adhesion. Sixty-four SD rats of clean grade were inflicted with electrical burn for the collection of serum of rats with electrical burn; another group of twenty-four SD rats were used to obtain normal serum without treatment. (1) Human monocyte line THP-1 was routinely cultured. The THP-1 cells in logarithmic phase were divided into normal serum group (resuspended in RPMI 1640 medium with 20% normal rat serum) and burn serum group (resuspended with RPMI 1640 medium with 20% serum of rats with electrical burn) according to the random number table, with 6 wells in each group. Morphology of THP-1 cells in normal serum group was observed at post culture hour (PCH) 24, and that in burn serum group at PCH 3, 6, 24. The contents of TNF-α in culture supernatant were determined by double-antibody sandwich ELISA at the corresponding time point in each group. The state of Akt activation was determined by Western blotting at PCH 3, 6, 24. (2) Another portion of THP-1 cells were divided into 4 groups according to the random number table, with 6 wells in each group. Cells in normal serum group and burn serum group were given with the same culture condition as above; cells in normal serum+inhibitor group and burn serum+inhibitor group were cultured with the same culture conditions as in the former two groups correspondingly with addition of 100 nmol/L wortmannin in the nutrient solution. At PCH 3 and 6, THP-1 cells were added into the well with a monolayer of endothelial cell line EA.hy926 to observe the monocyte-endothelial cell adhesion. Data were processed with one-way analysis of variance and LSD- t test. (1) In normal serum group, THP-1 cells showed growth in suspension, with uniform shape at PCH 24. In burn serum group, the cell shape became

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.

Statins affect the presentation of endothelial chemokines by targeting to multivesicular bodies.

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Johanna Hol

Full Text Available BACKGROUND: In addition to lowering cholesterol, statins are thought to beneficially modulate inflammation. Several chemokines including CXCL1/growth-related oncogene (GRO-α, CXCL8/interleukin (IL-8 and CCL2/monocyte chemoattractant protein (MCP-1 are important in the pathogenesis of atherosclerosis and can be influenced by statin-treatment. Recently, we observed that atorvastatin-treatment alters the intracellular content and subcellular distribution of GRO-α in cultured human umbilical vein endothelial cells (HUVECs. The objective of this study was to investigate the mechanisms involved in this phenomenon. METHODOLOGY/ PRINCIPAL FINDINGS: The effect of atorvastatin on secretion levels and subcellular distribution of GRO-α, IL-8 and MCP-1 in HUVECs activated by interleukin (IL-1β were evaluated by ELISA, confocal microscopy and immunoelectron microscopy. Atorvastatin increased the intracellular contents of GRO-α, IL-8, and MCP-1 and induced colocalization with E-selectin in multivesicular bodies. This effect was prevented by adding the isoprenylation substrate GGPP, but not the cholesterol precursor squalene, indicating that atorvastatin exerts these effects by inhibiting isoprenylation rather than depleting the cells of cholesterol. CONCLUSIONS/ SIGNIFICANCE: Atorvastatin targets inflammatory chemokines to the endocytic pathway and multivesicular bodies and may contribute to explain the anti-inflammatory effect of statins at the level of endothelial cell function.

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

Influence of layer-by-layer assembled electrospun poly (L-lactic acid) nanofiber mats on the bioactivity of endothelial cells

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Wu, Keke; Zhang, Xiazhi; Yang, Wufeng; Liu, Xiaoyan; Jiao, Yanpeng; Zhou, Changren

2016-12-01

Electrospun poly(L-lactic acid) (PLLA) nanofiber mats were successfully modified by deposition of multilayers with chitosan (CS), heparin (Hep) and graphene oxide (GO) through electrostatic layer-by-layer (LBL) self-assembly method. In this study, the surface properties of PLLA nanofiber mats before and after modification were investigated via scanning electron microscope (SEM), atomic force microscopy (AFM), attenuated total reflectance fourier transformation infrared spectroscopy (ATR-FTIR), X-ray photoelectron spectroscopy (XPS) and water contact angle measurement. In addition, the cytocompatibility of the modified PLLA nanofiber mats were investigated by testing endothelial cells compatibility, including cell attachment, cell proliferation and cell cycle. The results revealed that the surfaces of modified PLLA nanofiber mats become much rougher, stifiness and the hydrophilicity of the LBL modified PLLA nanofiber mats were improved compared to original PLLA one. Moreover, the modified PLLA nanofiber mats had promoted the endothelial cells viability attachment significantly. Besides, we studied the PLLA nanofiber mats on the expression of necrosis factor (TNF-α), interleukine-1β (IL-1β), monocyte chemoattractant protein-1 (MCP-1) and vascular cell adhesion molecule-1 (VCAM-1) in endothelial cells. The results showed that modified PLLA nanofiber mats had inhibited the inflammatory response to some extent.

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.

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.

Urine Epidermal Growth Factor, Monocyte Chemoattractant Protein-1 or Their Ratio as Biomarkers for Interstitial Fibrosis and Tubular Atrophy in Primary Glomerulonephritis

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Supanat Worawichawong

2016-12-01

Full Text Available Background/Aims: The degree of tubular atrophy and interstitial fibrosis (IFTA is an important prognostic factor in glomerulonephritis. Imbalance between pro-inflammatory cytokines such as monocyte chemoattractant protein- 1 (MCP-1 and protective cytokines such as epidermal growth factor (EGF likely determine IFTA severity. In separate studies, elevated MCP-1 and decreased EGF have been shown to be associated with IFTA severity. In this study, we aim to evaluate the predictive value of urinary EGF/MCP-1 ratio compared to each biomarker individually for moderate to severe IFTA in primary glomerulonephritis (GN. Methods: Urine samples were collected at biopsy from primary GN (IgA nephropathy, focal and segmental glomerulosclerosis, minimal change disease, membranous nephropathy. MCP-1 and EGF were analyzed by enzyme-linked immunosorbent assay. Results: EGF, MCP-1 and EGF/MCP-1 ratio from primary GN, all correlated with IFTA (n=58. By univariate analysis, glomerular filtration rate, EGF, and EGF/MCP-1 ratio were associated with IFTA. By multivariate analysis, only EGF/MCP-1 ratio was independently associated with IFTA. EGF/MCP-1 ratio had a sensitivity of 88% and specificity of 74 % for IFTA. EGF/MCP-1 had good discrimination for IFTA (AUC=0.85, but the improvement over EGF alone was not significant. Conclusion: EGF/MCP-1 ratio is independently associated IFTA severity in primary glomerulonephritis, but the ability of EGF/MCP-1 ratio to discriminate moderate to severe IFTA may not be much better than EGF alone.

Monocyte chemoattractant protein-1 promoter -2518 polymorphism and susceptibility to vasculitis, rheumatoid arthritis, and multiple sclerosis: A meta-analysis.

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Lee, Y H; Bae, S-C

2016-03-20

The purpose of this study was to examine whether the monocyte chemoattractant protein-1 (MCP-1) promoter -2518 A/G polymorphism (rs1024611) is associated with susceptibility to vasculitis, rheumatoid arthritis (RA), or multiple sclerosis (MS). A meta-analysis was conducted on the association between the MCP-1 -2518 A/G polymorphism and vasculitis, RA, and MS. Fourteen studies from 13 articles, including six on vasculitis, five on RA, and three on MS, consisting of 3,038 patients and 3,545 controls were available for the meta-analysis. The meta-analysis revealed no association between the MCP-1 -2518 G allele and vasculitis (odds ratio [OR] = 0.990, 95% confidence interval [CI] = 0.749-1.309, p = 0.943). Stratification by ethnicity indicated no association between the G allele of the MCP-1 -2518 A/G polymorphism and vasculitis in Asians and Caucasians. Meta-analysis by vasculitis type revealed an association between the GG+GA genotype of the MCP-1 -2518 A/G polymorphism and Behçet's disease (BD; OR = 1.349, 95% CI = 1.013-1.796, p = 0.040). However, sensitivity analysis showed that the association was not statistically significant after removing a study that was conducted in China (OR = 1.030, 95% CI = 0.667-1.590, p = 0.895), which indicated that the association was not statistically robust. The meta-analysis revealed no association between the MCP-1 -2518 G allele and RA (OR = 0.986, 95% CI = 0.890-1.093, p = 0.793) or MS (OR = 1.281, 95% CI = 0.802-2.046, p = 0.301). Our meta-analysis demonstrates that the MCP-1 -2518 A/G polymorphism is not associated with susceptibility to vasculitis, RA, or MS.

Circulating monocyte chemoattractant protein‐1 (MCP‐1) is associated with cachexia in treatment‐naïve pancreatic cancer patients

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Talbert, Erin E.; Lewis, Heather L.; Farren, Matthew R.; Ramsey, Mitchell L.; Chakedis, Jeffery M.; Rajasekera, Priyani; Haverick, Ericka; Sarna, Angela; Bloomston, Mark; Pawlik, Timothy M.; Zimmers, Teresa A.; Lesinski, Gregory B.; Hart, Phil A.; Dillhoff, Mary E.; Schmidt, Carl R.

2018-01-01

Abstract Background Cancer‐associated wasting, termed cancer cachexia, has a profound effect on the morbidity and mortality of cancer patients but remains difficult to recognize and diagnose. While increases in circulating levels of a number of inflammatory cytokines have been associated with cancer cachexia, these associations were generally made in patients with advanced disease and thus may be associated with disease progression rather than directly with the cachexia syndrome. Thus, we sought to assess potential biomarkers of cancer‐induced cachexia in patients with earlier stages of disease. Methods A custom multiplex array was used to measure circulating levels of 25 soluble factors from 70 pancreatic cancer patients undergoing attempted tumour resections. A high‐sensitivity multiplex was used for increased sensitivity for nine cytokines. Results Resectable pancreatic cancer patients with cachexia had low levels of canonical pro‐inflammatory cytokines including interleukin‐6 (IL‐6), interleukin‐1β (IL‐1β), interferon‐γ (IFN‐γ), and tumour necrosis factor (TNF). Even in our more sensitive analysis, these cytokines were not associated with cancer cachexia. Of the 25 circulating factors tested, only monocyte chemoattractant protein‐1 (MCP‐1) was increased in treatment‐naïve cachectic patients compared with weight stable patients and identified as a potential biomarker for cancer cachexia. Although circulating levels of leptin and granulocyte‐macrophage colony‐stimulating factor (GM‐CSF) were found to be decreased in the same cohort of treatment‐naïve cachectic patients, these factors were closely associated with body mass index, limiting their utility as cancer cachexia biomarkers. Conclusions Unlike in advanced disease, it is possible that cachexia in patients with resectable pancreatic cancer is not associated with high levels of classical markers of systemic inflammation. However, cachectic, treatment‐naïve patients

HSP27 Inhibits Homocysteine-Induced Endothelial Apoptosis by Modulation of ROS Production and Mitochondrial Caspase-Dependent Apoptotic Pathway

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Xin Tian

2016-01-01

Full Text Available Objectives. Elevated plasma homocysteine (Hcy could lead to endothelial dysfunction and is viewed as an independent risk factor for atherosclerosis. Heat shock protein 27 (HSP27, a small heat shock protein, is reported to exert protective effect against atherosclerosis. This study aims to investigate the protective effect of HSP27 against Hcy-induced endothelial cell apoptosis in human umbilical vein endothelial cells (HUVECs and to determine the underlying mechanisms. Methods. Apoptosis, reactive oxygen species (ROS, and mitochondrial membrane potential (MMP of normal or HSP27-overexpressing HUVECs in the presence of Hcy were analyzed by flow cytometry. The mRNA and protein expression levels were measured by quantitative real-time polymerase chain reaction (qRT-PCR and western blot. Results. We found that Hcy could induce cell apoptosis with corresponding decrease of nitric oxide (NO level, increase of endothelin-1 (ET-1, intracellular adhesion molecule-1 (ICAM-1, vascular cellular adhesion molecule-1 (VCAM-1, and monocyte chemoattractant protein-1 (MCP-1 levels, elevation of ROS, and dissipation of MMP. In addition, HSP27 could protect the cell against Hcy-induced apoptosis and inhibit the effect of Hcy on HUVECs. Furthermore, HSP27 could increase the ratio of Bcl-2/Bax and inhibit caspase-3 activity. Conclusions. Therefore, we concluded that HSP27 played a protective role against Hcy-induced endothelial apoptosis through modulation of ROS production and the mitochondrial caspase-dependent apoptotic pathway.

Role of atrial endothelial cells in the development of atrial fibrosis and fibrillation in response to pressure overload.

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Kume, Osamu; Teshima, Yasushi; Abe, Ichitaro; Ikebe, Yuki; Oniki, Takahiro; Kondo, Hidekazu; Saito, Shotaro; Fukui, Akira; Yufu, Kunio; Miura, Masahiro; Shimada, Tatsuo; Takahashi, Naohiko

Monocyte chemoattractant protein-1 (MCP-1)-mediated inflammatory mechanisms have been shown to play a crucial role in atrial fibrosis induced by pressure overload. In the present study, we investigated whether left atrial endothelial cells would quickly respond structurally and functionally to pressure overload to trigger atrial fibrosis and fibrillation. Six-week-old male Sprague-Dawley rats underwent suprarenal abdominal aortic constriction (AAC) or a sham operation. By day 3 after surgery, macrophages were observed to infiltrate into the endocardium. The expression of MCP-1 and E-selectin in atrial endothelium and the expression of intercellular adhesion molecule-1, vascular cell adhesion molecule-1, and ED1 in left atrial tissue were enhanced. Atrial endothelial cells were irregularly hypertrophied with the disarrangement of lines of cells by scanning electron microscopy. Various-sized gap formations appeared along the border in atrial endothelial cells, and several macrophages were located just in the endothelial gap. Along with the development of heterogeneous interstitial fibrosis, interatrial conduction time was prolonged and the inducibility of atrial fibrillation by programmed extrastimuli was increased in the AAC rats compared to the sham-operated rats. Atrial endothelium responds rapidly to pressure overload by expressing adhesion molecules and MCP-1, which induce macrophage infiltration into the atrial tissues. These processes could be an initial step in the development of atrial remodeling for atrial fibrillation. Copyright © 2016 Elsevier Inc. All rights reserved.

Resuscitation Strategies for Burn Injuries Sustained in Austere Environments to Improve Renal Perfusion and Function

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2017-10-01

monocyte chemoattractant protein 1; MAP, mean arterial pressure; HIF, hypoxic inducible factor; VEGF, vascular endothelial growth factor; ROS, reactive...TNF-α, tumor necrosis factor-α; AQP, aquaporin; GSH, glutathione; MDA, malondialdehyde; TBARS, thiobarbituric acid-reactive substances; MPO...shrunken glomeruli were present and tubular necrosis was demon- strated by detached basal lamina [42]. Similarly, while models of electrical burns

Influence of layer-by-layer assembled electrospun poly (L-lactic acid) nanofiber mats on the bioactivity of endothelial cells

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Wu, Keke; Zhang, Xiazhi; Yang, Wufeng; Liu, Xiaoyan; Jiao, Yanpeng, E-mail: tjiaoyp@jnu.edu.cn; Zhou, Changren

2016-12-30

Highlights: • Layer-by-layer assembled PLLA nanofiber mats were successfully prepared. • The modified PLLA nanofiber mats enhanced the adhesion, proliferation of endothelial cells. • The modified PLLA nanofiber mats had inhibited the inflammatory response to some extent. - Abstract: Electrospun poly(L-lactic acid) (PLLA) nanofiber mats were successfully modified by deposition of multilayers with chitosan (CS), heparin (Hep) and graphene oxide (GO) through electrostatic layer-by-layer (LBL) self-assembly method. In this study, the surface properties of PLLA nanofiber mats before and after modification were investigated via scanning electron microscope (SEM), atomic force microscopy (AFM), attenuated total reflectance fourier transformation infrared spectroscopy (ATR-FTIR), X-ray photoelectron spectroscopy (XPS) and water contact angle measurement. In addition, the cytocompatibility of the modified PLLA nanofiber mats were investigated by testing endothelial cells compatibility, including cell attachment, cell proliferation and cell cycle. The results revealed that the surfaces of modified PLLA nanofiber mats become much rougher, stifiness and the hydrophilicity of the LBL modified PLLA nanofiber mats were improved compared to original PLLA one. Moreover, the modified PLLA nanofiber mats had promoted the endothelial cells viability attachment significantly. Besides, we studied the PLLA nanofiber mats on the expression of necrosis factor (TNF-α), interleukine-1β (IL-1β), monocyte chemoattractant protein-1 (MCP-1) and vascular cell adhesion molecule-1 (VCAM-1) in endothelial cells. The results showed that modified PLLA nanofiber mats had inhibited the inflammatory response to some extent.

Upregulation of endothelial cell adhesion molecules characterizes veins close to granulomatous infiltrates in the renal cortex of cats with feline infectious peritonitis and is indirectly triggered by feline infectious peritonitis virus-infected monocytes in vitro.

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Acar, Delphine D; Olyslaegers, Dominique A J; Dedeurwaerder, Annelike; Roukaerts, Inge D M; Baetens, Wendy; Van Bockstael, Sebastiaan; De Gryse, Gaëtan M A; Desmarets, Lowiese M B; Nauwynck, Hans J

2016-10-01

One of the most characteristic pathological changes in cats that have succumbed to feline infectious peritonitis (FIP) is a multifocal granulomatous phlebitis. Although it is now well established that leukocyte extravasation elicits the inflammation typically associated with FIP lesions, relatively few studies have aimed at elucidating this key pathogenic event. The upregulation of adhesion molecules on the endothelium is a prerequisite for stable leukocyte-endothelial cell (EC) adhesion that necessarily precedes leukocyte diapedesis. Therefore, the present work focused on the expression of the EC adhesion molecules and possible triggers of EC activation during the development of FIP. Immunofluorescence analysis revealed that the endothelial expression of P-selectin, E-selectin, intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1) was elevated in veins close to granulomatous infiltrates in the renal cortex of FIP patients compared to non-infiltrated regions and specimens from healthy cats. Next, we showed that feline venous ECs become activated when exposed to supernatant from feline infectious peritonitis virus (FIPV)-infected monocytes, as indicated by increased adhesion molecule expression. Active viral replication seemed to be required to induce the EC-stimulating activity in monocytes. Finally, adhesion assays revealed an increased adhesion of naive monocytes to ECs treated with supernatant from FIPV-infected monocytes. Taken together, our results strongly indicate that FIPV activates ECs to increase monocyte adhesion by an indirect route, in which proinflammatory factors released from virus-infected monocytes act as key intermediates.

Dopamine attenuates the chemoattractant effect of interleukin-8: a novel role in the systemic inflammatory response syndrome.

LENUS (Irish Health Repository)

Sookhai, S

2012-02-03

Activated neutrophil (PMN) adherence to vascular endothelium comprises a key step for both transendothelial migration and initiation of potentially deleterious release of PMN products. The biogenic amine, dopamine (DA), has been used for several decades in patients to maintain hemodynamic stability. The effect of dopamine on PMN transendothelial migration and adhesion receptor expression and on the endothelial molecules, E-selectin and ICAM-1, was evaluated. PMN were isolated from healthy controls, stimulated with lipopolysaccharide (LPS), and tumor necrosis factor-alpha (TNF-alpha) and treated with dopamine. CD 11b and CD 18 PMN adhesion receptor expression were assessed flow cytometrically. In a separate experiment, the chemoattractant peptide, IL-8, was placed in the lower chamber of transwells, and PMN migration was assessed. Human umbilical vein endothelial cells (HUVEC) were stimulated with LPS\\/TNF-alpha and incubated with dopamine. ICAM-1 and E-selectin endothelial molecule expression were assessed flow cytometrically. There was a significant increase in transendothelial migration in stimulated PMN compared with normal PMN (40 vs. 14%, P < 0.001). In addition, PMN CD11b\\/CD18 was significantly upregulated in stimulated PMN compared with normal PMN (252.4\\/352.4 vs. 76.7\\/139.4, P < 0.001) as were endothelial E-selectin\\/ICAM-1 expression compared with normal EC (8.1\\/9 vs. 3.9\\/3.8, P < 0.05). After treatment with dopamine, PMN transmigration was significantly decreased compared with stimulated PMN (8% vs. 40%, P < 0.001). Furthermore, dopamine also attenuated PMN CD11b\\/CD18 and the endothelial molecules E-selectin and ICAM-1 compared with stimulated PMN\\/EC that were not treated dopamine (174\\/240 vs. 252\\/352, P < 0.05 and 4\\/4.4 vs. 8.1\\/9, P < 0.05. respectively). The chemoattractant effect of IL-8 was also attenuated. These results identify for the first time that dopamine attenuates the initial interaction between PMN and the endothelium

Apoptosis of Endothelial Cells by 13-HPODE Contributes to Impairment of Endothelial Barrier Integrity

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Valerie E. Ryman

2016-01-01

Full Text Available Inflammation is an essential host response during bacterial infections such as bovine mastitis. Endothelial cells are critical for an appropriate inflammatory response and loss of vascular barrier integrity is implicated in the pathogenesis of Streptococcus uberis-induced mastitis. Previous studies suggested that accumulation of linoleic acid (LA oxygenation products derived from 15-lipoxygenase-1 (15-LOX-1 metabolism could regulate vascular functions. The initial LA derivative from the 15-LOX-1 pathway, 13-hydroperoxyoctadecadienoic acid (HPODE, can induce endothelial death, whereas the reduced hydroxyl product, 13-hydroxyoctadecadienoic acid (HODE, is abundantly produced during vascular activation. However, the relative contribution of specific LA-derived metabolites on impairment of mammary endothelial integrity is unknown. Our hypothesis was that S. uberis-induced LA-derived 15-LOX-1 oxygenation products impair mammary endothelial barrier integrity by apoptosis. Exposure of bovine mammary endothelial cells (BMEC to S. uberis did not increase 15-LOX-1 LA metabolism. However, S. uberis challenge of bovine monocytes demonstrated that monocytes may be a significant source of both 13-HPODE and 13-HODE during mastitis. Exposure of BMEC to 13-HPODE, but not 13-HODE, significantly reduced endothelial barrier integrity and increased apoptosis. Changing oxidant status by coexposure to an antioxidant during 13-HPODE treatment prevented adverse effects of 13-HPODE, including amelioration of apoptosis. A better understanding of how the oxidant status of the vascular microenvironment impacts endothelial barrier properties could lead to more efficacious treatments for S. uberis mastitis.

Endothelial-regenerating cells: an expanding universe.

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Steinmetz, Martin; Nickenig, Georg; Werner, Nikos

2010-03-01

Atherosclerosis is the most common cause for cardiovascular diseases and is based on endothelial dysfunction. A growing body of evidence suggests the contribution of bone marrow-derived endothelial progenitor cells, monocytic cells, and mature endothelial cells to vessel formation and endothelial rejuvenation. To this day, various subsets of these endothelial-regenerating cells have been identified according to cellular origin, phenotype, and properties in vivo and in vitro. However, the definition and biology, especially of endothelial progenitor cells, is complex and under heavy debate. In this review, we focus on current definitions of endothelial progenitor cells, highlight the clinical relevance of endothelial-regenerating cells, and provide new insights into cell-cell interactions involved in endothelial cell rejuvenation.

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.

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.

Effect of AST-120 on Endothelial Dysfunction in Adenine-Induced Uremic Rats

Directory of Open Access Journals (Sweden)

Yuko Inami

2014-01-01

Full Text Available Aim. Chronic kidney disease (CKD represents endothelial dysfunction. Monocyte adhesion is recognized as the initial step of arteriosclerosis. Indoxyl sulfate (IS is considered to be a risk factor for arteriosclerosis in CKD. Oral adsorbent AST-120 retards deterioration of renal function, reducing accumulation of IS. In the present study, we determined the monocyte adhesion in the adenine-induced uremic rats in vivo and effects of AST-120 on the adhesion molecules. Methods. Twenty-four rats were divided into control, control+AST-120, adenine, and adenine+AST-120 groups. The number of monocytes adherent to the endothelium of thoracic aorta by imaging the entire endothelial surface and the mRNA expressions of adhesion and atherosclerosis-related molecules were examined on day 49. The mRNA expressions of ICAM-1 and VCAM-1 in human umbilical vein endothelial cells were also examined. Results. Adenine increased the number of adherent monocytes, and AST-120 suppressed the increase. The monocyte adhesion was related to serum creatinine and IS in sera. Overexpression of VCAM-1 and TGF-β1 mRNA in the arterial walls was observed in uremic rats. IS induced increase of the ICAM-1 and VCAM-1 mRNA expressions in vitro. Conclusion. It appears that uremic condition introduces the monocyte adhesion to arterial wall and AST-120 might inhibit increasing of the monocyte adherence with CKD progression.

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.

Invasive Streptococcus mutans induces inflammatory cytokine production in human aortic endothelial cells via regulation of intracellular toll-like receptor 2 and nucleotide-binding oligomerization domain 2.

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Nagata, E; Oho, T

2017-04-01

Streptococcus mutans, the primary etiologic agent of dental caries, can gain access to the bloodstream and has been associated with cardiovascular disease. However, the roles of S. mutans in inflammation in cardiovascular disease remain unclear. The aim of this study was to examine cytokine production induced by S. mutans in human aortic endothelial cells (HAECs) and to evaluate the participation of toll-like receptors (TLRs) and cytoplasmic nucleotide-binding oligomerization domain (NOD) -like receptors in HAECs. Cytokine production by HAECs was determined using enzyme-linked immunosorbent assays, and the expression of TLRs and NOD-like receptors was evaluated by real-time polymerase chain reaction, flow cytometry and immunocytochemistry. The involvement of TLR2 and NOD2 in cytokine production by invaded HAECs was examined using RNA interference. The invasion efficiencies of S. mutans strains were evaluated by means of antibiotic protection assays. Five of six strains of S. mutans of various serotypes induced interleukin-6, interleukin-8 and monocyte chemoattractant protein-1 production by HAECs. All S. mutans strains upregulated TLR2 and NOD2 mRNA levels in HAECs. Streptococcus mutans Xc upregulated the intracellular TLR2 and NOD2 protein levels in HAECs. Silencing of the TLR2 and NOD2 genes in HAECs invaded by S. mutans Xc led to a reduction in interleukin-6, interleukin-8 and monocyte chemoattractant protein-1 production. Cytokine production induced by invasive S. mutans via intracellular TLR2 and NOD2 in HAECs may be associated with inflammation in cardiovascular disease. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Adiponectin, interleukin-6, monocyte chemoattractant protein-1, and regional fat mass during 12-month randomized treatment with metformin and/or oral contraceptives in polycystic ovary syndrome.

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Glintborg, Dorte; Mumm, Hanne; Altinok, Magda Lambaa; Richelsen, Bjørn; Bruun, Jens Meldgaard; Andersen, Marianne

2014-08-01

Central obesity in polycystic ovary syndrome (PCOS) is associated with increased inflammatory markers and increased risk for type 2 diabetes. To evaluate if improved body composition during treatment with metformin (M) vs. oral contraceptive pills (OCP) was associated with changes in circulating adiponectin, interleukin (IL)-6, and monocyte chemoattractant protein (MCP)-1. Ninety patients with PCOS were randomized to 12-month treatment with M (2 g/day), M + OCP (150 mg desogestrel + 30 microgram ethinylestradiol) or OCP. Adiponectin, IL-6, MCP-1, whole body DXA scans, and clinical evaluations were performed before and after the intervention period in the 65 study completers. Changes in inflammatory markers and changes in total and regional fat mass estimates. Adiponectin, IL-6, and MCP-1 levels were unchanged during the three types of medical intervention. Treatment with M and M + OCP was superior to OCP regarding decreased regional fat mass. Baseline adiponectin and IL-6 were associated with BMI, waist, and trunk fat mass. Changes in trunk fat were significantly associated with changes in IL-6 and MCP-1 during M + OCP. Long-term treatment with M alone or in combination with OCP was associated with improved body composition compared to OCP, whereas inflammatory markers were unchanged. OCP was not associated with increased inflammatory markers despite a small but significant weight gain.

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

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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.

Vascular endothelial growth factor and protein level in pleural effusion for differentiating malignant from benign pleural effusion.

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Wu, Da-Wei; Chang, Wei-An; Liu, Kuan-Ting; Yen, Meng-Chi; Kuo, Po-Lin

2017-09-01

Pleural effusion is associated with multiple benign and malignant conditions. Currently no biomarkers differentiate malignant pleural effusion (MPE) and benign pleural effusion (BPE) sensitively and specifically. The present study identified a novel combination of biomarkers in pleural effusion for differentiating MPE from BPE by enrolling 75 patients, 34 with BPE and 41 with MPE. The levels of lactate dehydrogenase, glucose, protein, and total cell, neutrophil, monocyte and lymphocyte counts in the pleural effusion were measured. The concentrations of interleukin (IL)-1β, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12, tumor necrosis factor-α, interferon γ, transforming growth factor-β1, colony stimulating factor 2, monocyte chemoattractant protein-1 and vascular endothelial growth factor (VEGF) were detected using cytometric bead arrays. Protein and VEGF levels differed significantly between patients with BPE and those with MPE. The optimal cutoff value of VEGF and protein was 214 pg/ml and 3.35 g/dl respectively, according to the receiver operating characteristic curve. A combination of VEGF >214 pg/ml and protein >3.35 g/dl in pleural effusion presented a sensitivity of 92.6% and an accuracy of 78.6% for MPE, but was not associated with a decreased survival rate. These results suggested that this novel combination strategy may provide useful biomarkers for predicting MPE and facilitating early diagnosis.

CD16+ monocytes and skewed macrophage polarization toward M2 type hallmark heart transplant acute cellular rejection

NARCIS (Netherlands)

T.P.P. van den Bosch (Thierry); K. Caliskan (Kadir); M.D. Kraaij (Marina); A.A. Constantinescu (Alina); O.C. Manintveld (Olivier); P.J. Leenen (Pieter); J. von der Thusen (Jan); M.C. Clahsen-van Groningen (Marian); C.C. Baan (Carla); A.T. Rowshani (Ajda)

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

Manufacture of endothelial colony-forming progenitor cells from steady-state peripheral blood leukapheresis using pooled human platelet lysate.

Science.gov (United States)

Siegel, Georg; Fleck, Erika; Elser, Stefanie; Hermanutz-Klein, Ursula; Waidmann, Marc; Northoff, Hinnak; Seifried, Erhard; Schäfer, Richard

2018-05-01

Endothelial colony-forming progenitor cells (ECFCs) are promising candidates for cell therapies. However, ECFC translation to the clinic requires optimized isolation and manufacture technologies according to good manufacturing practice (GMP). ECFCs were manufactured from steady-state peripheral blood (PB) leukapheresis (11 donors), using GMP-compliant technologies including pooled human platelet (PLT) lysate, and compared to human umbilical cord endothelial cells, human aortic endothelial cells, and human cerebral microvascular endothelial cells. Specific variables assessed were growth kinetics, phenotype, trophic factors production, stimulation of tube formation, and Dil-AcLDL uptake. ECFCs could be isolated from PB leukapheresis units with mean processed volume of 5411 mL and mean white blood cell (WBC) concentration factor of 8.74. The mean frequency was 1.44 × 10 -8 ECFCs per WBC, corresponding to a mean of 177.8 ECFCs per apheresis unit. Expandable for up to 12 cumulative population doublings, calculated projection showed that approximately 730 × 10 3 ECFCs could be manufactured from 1 apheresis unit. ECFCs produced epidermal growth factor, hepatocyte growth factor, vascular endothelial growth factor (VEGF)-A, PLT-derived growth factor-B, interleukin-8, and monocyte chemoattractant protein-1, featured high potential for capillary-like tubes formation, and showed no telomerase activity. They were characterized by CD29, CD31, CD44, CD105, CD117, CD133, CD144, CD146, and VEGF-R2 expression, with the most common subpopulation CD34+CD117-CD133-. Compared to controls, ECFCs featured greater Dil-AcLDL uptake and higher expression of CD29, CD31, CD34, CD44, CD144, and VEGF-R2. Here we show that isolation of ECFCs with proangiogenic profile from steady-state PB leukapheresis is feasible, marking a first step toward ECFC product manufacture according to GMP. © 2018 AABB.

Protein hydrolysate from canned sardine and brewing by-products improves TNF-α-induced inflammation in an intestinal-endothelial co-culture cell model.

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Vieira, Elsa F; Van Camp, John; Ferreira, Isabel M P L V O; Grootaert, Charlotte

2017-07-17

The anti-inflammatory activity of sardine protein hydrolysates (SPH) obtained by hydrolysis with proteases from brewing yeast surplus was ascertained. For this purpose, a digested and desalted SPH fraction with molecular weight lower than 10 kDa was investigated using an endothelial cell line (EA.hy926) as such and in a co-culture model with an intestinal cell line (Caco-2). Effects of SPH <10 kDa on nitric oxide (NO) production, reactive oxygen species (ROS) inhibition and secretion of monocyte chemoattractant protein 1 (MCP-1), vascular endothelial growth factor (VEGF), chemokine IL-8 (IL-8) and intercellular adhesion molecule-1 (ICAM-1) were evaluated in TNF-α-treated and untreated cells. Upon TNF-α treatment, levels of NO, MCP-1, VEGF, IL-8, ICAM-1 and endothelial ROS were significantly increased in both mono- and co-culture models. Treatment with SPH <10 kDa (2.0 mg peptides/mL) significantly decreased all the inflammation markers when compared to TNF-α-treated control. This protective effect was more pronounced in the co-culture model, suggesting that SPH <10 kDa Caco-2 cells metabolites produced in the course of intestinal absorption may provide a more relevant protective effect against endothelial dysfunction. Additionally, indirect cross-talk between two cell types was established, suggesting that SPH <10 kDa may also bind to receptors on the Caco-2 cells, thereby triggering a pathway to secrete the pro-inflammatory compounds. Overall, these in vitro screening results, in which intestinal digestion, absorption and endothelial bioactivity are simulated, show the potential of SPH to be used as a functional food with anti-inflammatory properties.

Niacin results in reduced monocyte adhesion in patients with type 2 diabetes mellitus.

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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.

Entamoeba lysyl-tRNA synthetase contains a cytokine-like domain with chemokine activity towards human endothelial cells.

Directory of Open Access Journals (Sweden)

Manuel Castro de Moura

2011-11-01

Full Text Available Immunological pressure encountered by protozoan parasites drives the selection of strategies to modulate or avoid the immune responses of their hosts. Here we show that the parasite Entamoeba histolytica has evolved a chemokine that mimics the sequence, structure, and function of the human cytokine HsEMAPII (Homo sapiens endothelial monocyte activating polypeptide II. This Entamoeba EMAPII-like polypeptide (EELP is translated as a domain attached to two different aminoacyl-tRNA synthetases (aaRS that are overexpressed when parasites are exposed to inflammatory signals. EELP is dispensable for the tRNA aminoacylation activity of the enzymes that harbor it, and it is cleaved from them by Entamoeba proteases to generate a standalone cytokine. Isolated EELP acts as a chemoattractant for human cells, but its cell specificity is different from that of HsEMAPII. We show that cell specificity differences between HsEMAPII and EELP can be swapped by site directed mutagenesis of only two residues in the cytokines' signal sequence. Thus, Entamoeba has evolved a functional mimic of an aaRS-associated human cytokine with modified cell specificity.

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 ...

Characterization of a receptor for human monocyte-derived neutrophil chemotactic factor/interleukin-8

International Nuclear Information System (INIS)

Grob, P.M.; David, E.; Warren, T.C.; DeLeon, R.P.; Farina, P.R.; Homon, C.A.

1990-01-01

Monocyte-derived neutrophil chemotactic factor/interleukin-8 (MDNCF/IL-8) is an 8,000-dalton protein produced by monocytes which exhibits activity as a chemoattractant for neutrophils with maximal activity achieved at a concentration of 50 ng/ml. This polypeptide has been iodinated by chloramine-T methodology (350 Ci/mM), and specific receptors for MDNCF/IL-8 have been detected on human neutrophils, U937 cells, THP-1 cells, and dimethyl sulfoxide-differentiated HL-60 cells. The binding of MDNCF/IL-8 to human neutrophils is not inhibited by interleukin-1 alpha, tumor necrosis factor-alpha, insulin, or epidermal growth factor. In addition, chemoattractants such as C5a, fMet-Leu-Phe, leukotriene B4, and platelet-activating factor fail to inhibit binding, suggesting that MDNCF/IL-8 utilizes a unique receptor. The receptor for MDNCF/IL-8 is apparently glycosylated since ligand binding is inhibited by the presence of wheat germ agglutinin, a lectin with a binding specificity for N-acetylglucosamine and neuraminic acid. Steady state binding experiments indicate Kd values of 4 and 0.5 nM and receptor numbers of 75,000 and 7,400 for human neutrophils and differentiated HL-60 cells, respectively. 125I-MDNCF/IL-8 bound to human neutrophils is rapidly internalized and subsequently released from cells as trichloroacetic acid-soluble radioactivity. Affinity labeling experiments suggest that the human neutrophil MDNCF/IL-8 receptor exhibits a mass of approximately 58,000 daltons

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.

Anthocyanin prevents CD40-activated proinflammatory signaling in endothelial cells by regulating cholesterol distribution.

Science.gov (United States)

Xia, Min; Ling, Wenhua; Zhu, Huilian; Wang, Qing; Ma, Jing; Hou, Mengjun; Tang, Zhihong; Li, Lan; Ye, Qinyuan

2007-03-01

Intracellular tumor necrosis factor receptor-associated factors (TRAFs) translocation to lipid rafts is a key element in CD40-induced signaling. The purpose of this study was to investigate the influence of anthocyanin on CD40-mediated proinflammatory events in human endothelial cells and the underlying possible molecular mechanism. Treatment of endothelial cells with anthocyanin prevented from CD40-induced proinflammatory status, measured by production of IL-6, IL-8, and monocyte chemoattractant protein-1 through inhibiting CD40-induced nuclear factor-kappaB (NF-kappaB) activation. TRAF-2 played pivotal role in CD40-NF-kappaB pathway as TRAF-2 small interference RNA (siRNA) diminished CD40-induced NF-kappaB activation and inflammation. TRAF-2 overexpression increased CD40-mediated NF-kappaB activation. Moreover, TRAF-2 almost totally recruited to lipid rafts after stimulation by CD40 ligand and depletion of cholesterol diminished CD40-mediated NF-kappaB activation. Exposure to anthocyanin not only interrupted TRAF-2 recruitment to lipid rafts but also decreased cholesterol content in Triton X-100 insoluble lipid rafts. However, anthocyanin did not influence the interaction between CD40 ligand and CD40 receptor. Our findings suggest that anthocyanin protects from CD40-induced proinflammatory signaling by preventing TRAF-2 translocation to lipid rafts through regulation of cholesterol distribution, which thereby may represent a mechanism that would explain the anti-inflammatory response of anthocyanin.

Endothelial monocyte activating polypeptide-II modulates endothelial cell responses by degrading hypoxia-inducible factor-1alpha through interaction with PSMA7, a component of the proteasome

International Nuclear Information System (INIS)

Tandle, Anita T.; Calvani, Maura; Uranchimeg, Badarch; Zahavi, David; Melillo, Giovanni; Libutti, Steven K.

2009-01-01

The majority of human tumors are angiogenesis dependent. Understanding the specific mechanisms that contribute to angiogenesis may offer the best approach to develop therapies to inhibit angiogenesis in cancer. Endothelial monocyte activating polypeptide-II (EMAP-II) is an anti-angiogenic cytokine with potent effects on endothelial cells (ECs). It inhibits EC proliferation and cord formation, and it suppresses primary and metastatic tumor growth in-vivo. However, very little is known about the molecular mechanisms behind the anti-angiogenic activity of EMAP-II. In the present study, we explored the molecular mechanism behind the anti-angiogenic activity exerted by this protein on ECs. Our results demonstrate that EMAP-II binds to the cell surface α5β1 integrin receptor. The cell surface binding of EMAP-II results in its internalization into the cytoplasmic compartment where it interacts with its cytoplasmic partner PSMA7, a component of the proteasome degradation pathway. This interaction increases hypoxia-inducible factor 1-alpha (HIF-1α) degradation under hypoxic conditions. The degradation results in the inhibition of HIF-1α mediated transcriptional activity as well as HIF-1α mediated angiogenic sprouting of ECs. HIF-1α plays a critical role in angiogenesis by activating a variety of angiogenic growth factors. Our results suggest that one of the major anti-angiogenic functions of EMAP-II is exerted through its inhibition of the HIF-1α activities.

Endothelial monocyte activating polypeptide-II modulates endothelial cell responses by degrading hypoxia-inducible factor-1alpha through interaction with PSMA7, a component of the proteasome

Energy Technology Data Exchange (ETDEWEB)

Tandle, Anita T. [Tumor Angiogenesis Section, Surgery Branch, Center for Cancer Research, National Cancer Institute, Bethesda, Maryland 20892 (United States); Calvani, Maura; Uranchimeg, Badarch [DTP-Tumor Hypoxia Laboratory, SAIC Frederick, Inc., National Cancer Institute, Frederick, Maryland 21702 (United States); Zahavi, David [Tumor Angiogenesis Section, Surgery Branch, Center for Cancer Research, National Cancer Institute, Bethesda, Maryland 20892 (United States); Melillo, Giovanni [DTP-Tumor Hypoxia Laboratory, SAIC Frederick, Inc., National Cancer Institute, Frederick, Maryland 21702 (United States); Libutti, Steven K., E-mail: slibutti@montefiore.org [Department of Surgery, Montefiore-Einstein Center for Cancer Care, Albert Einstein College of Medicine, Greene Medical Arts Pavilion, 4th Floor 3400, Bainbridge Avenue, Bronx, New York 10467 (United States)

2009-07-01

The majority of human tumors are angiogenesis dependent. Understanding the specific mechanisms that contribute to angiogenesis may offer the best approach to develop therapies to inhibit angiogenesis in cancer. Endothelial monocyte activating polypeptide-II (EMAP-II) is an anti-angiogenic cytokine with potent effects on endothelial cells (ECs). It inhibits EC proliferation and cord formation, and it suppresses primary and metastatic tumor growth in-vivo. However, very little is known about the molecular mechanisms behind the anti-angiogenic activity of EMAP-II. In the present study, we explored the molecular mechanism behind the anti-angiogenic activity exerted by this protein on ECs. Our results demonstrate that EMAP-II binds to the cell surface {alpha}5{beta}1 integrin receptor. The cell surface binding of EMAP-II results in its internalization into the cytoplasmic compartment where it interacts with its cytoplasmic partner PSMA7, a component of the proteasome degradation pathway. This interaction increases hypoxia-inducible factor 1-alpha (HIF-1{alpha}) degradation under hypoxic conditions. The degradation results in the inhibition of HIF-1{alpha} mediated transcriptional activity as well as HIF-1{alpha} mediated angiogenic sprouting of ECs. HIF-1{alpha} plays a critical role in angiogenesis by activating a variety of angiogenic growth factors. Our results suggest that one of the major anti-angiogenic functions of EMAP-II is exerted through its inhibition of the HIF-1{alpha} activities.

Suppression of endothelial cell adhesion by XJP-1, a new phenolic compound derived from banana peel.

Science.gov (United States)

Fu, Rong; Yan, Tianhua; Wang, Qiujuan; Guo, Qinglong; Yao, Hequan; Wu, Xiaoming; Li, Yang

2012-01-01

The adhesion of monocytes to activated vascular endothelial cells is a critical event in the initiation of atherosclerosis. Adhesion is mediated by oxidized low-density lipoprotein (ox-LDL) which up-regulates inflammatory markers on endothelial cells. Here we report that (±) 7, 8-dihydroxy-3-methyl-isochromanone-4 (XJP-1), an inhibitor of ox-LDL-induced adhesion of monocytes to endothelial cells blocks cellular functions which are associated with adhesion. We show that XJP-1 down-regulates ox-LDL-induced over-expression of adhesion molecules (ICAM-1 and VCAM-1) in a dose-dependent manner in human umbilical vein endothelial cells (HUVECs), attenuates ox-LDL-induced up-regulation of low-density lipoprotein receptor (LOX)-1, decreases generation of reactive oxygen species (ROS), blocks translocation of nuclear factor-kappa B (NF-κB) activity, and prevents activation of c-Jun N-terminal kinase (JNK)/p38 pathways in endothelial cells. These findings suggest that XJP-1 may attenuate ox-LDL-induced endothelial adhesion of monocytes by blocking expression of adhesion molecules through suppressing ROS/NF-κB, JNK and p38 pathways. Copyright © 2012 Elsevier Inc. All rights reserved.

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.

Novel effects of edaravone on human brain microvascular endothelial cells revealed by a proteomic approach.

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Onodera, Hidetaka; Arito, Mitsumi; Sato, Toshiyuki; Ito, Hidemichi; Hashimoto, Takuo; Tanaka, Yuichiro; Kurokawa, Manae S; Okamoto, Kazuki; Suematsu, Naoya; Kato, Tomohiro

2013-10-09

Edaravone (3-methyl-1-phenyl-2-pyrazolin-5-one) is a free radical scavenger used for acute ischemic stroke. However, it is not known whether edaravone works only as a free radical scavenger or possess other pharmacological actions. Therefore, we elucidated the effects of edaravone on human brain microvascular endothelial cells (HBMECs) by 2 dimensional fluorescence difference gel electrophoresis (2D-DIGE). We found 38 protein spots the intensity of which was significantly altered 1.3 fold on average (pedaravone treatment and successfully identified 17 proteins of those. Four of those 17 proteins were cytoskeleton proteins or cytoskeleton-regulating proteins. Therefore, we subsequently investigated the change of size and shape of the cells, the actin network, and the tight junction of HBMEC by immunocytochemistry. As a result, most edaravone-treated HBMECs became larger and rounder compared with those that were not treated. Furthermore, edaravone-treated HBMECs formed gathering zona occludens (ZO)-1, a tight junction protein, along the junction of the cells. In addition, we found that edaravone suppressed interleukin (IL)-1β-induced secretion of monocyte chemoattractant protein-1 (MCP-1), which was reported to increase cell permeability. We found a novel function of edaravone is the promotion of tight junction formations of vascular endothelial cells partly via the down-regulation of MCP-1 secretion. These data provide fundamental and useful information in the clinical use of edaravone in patients with cerebral vascular diseases. © 2013 Elsevier B.V. All rights reserved.

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.

The biophysical model for accuracy of cellular sensing spatial gradients of multiple chemoattractants

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Chang, Qiang; Zuo, Li

2013-01-01

Spatial gradients of surrounding chemoattractants are the key factors in determining the directionality of eukaryotic cell movement. Thus, it is important for cells to accurately measure the spatial gradients of surrounding chemoattractants. Here, we study the precision of sensing the spatial gradients of multiple chemoattractants using cooperative receptor clusters. Cooperative receptors on cells are modeled as an Ising chain of Monod–Wyman–Changeux clusters subject to multiple chemical-gradient fields to study the physical limits of multiple chemoattractants spatial gradients sensing. We found that eukaryotic cells cannot sense each chemoattractant gradient individually. Instead, cells can only sense a weighted sum of surrounding chemical gradients. Moreover, the precision of sensing one chemical gradient is signicantly affected by coexisting chemoattractant concentrations. These findings can provide a further insight into the role of chemoattractants in immune response and help develop novel treatments for inflammatory diseases. (paper)

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.

Interactions of TLR4 and PPARγ, Dependent on AMPK Signalling Pathway Contribute to Anti-Inflammatory Effects of Vaccariae Hypaphorine in Endothelial Cells

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Haijian Sun

2017-07-01

Full Text Available Background /Aims: Accumulating evidence indicates that endothelial inflammation is one of the critical determinants in pathogenesis of atherosclerotic cardiovascular disease. Our previous studies had demonstrated that Vaccariae prevented high glucose or oxidative stress-triggered endothelial dysfunction in vitro. Very little is known about the potential effects of hypaphorine from Vaccariae seed on inflammatory response in endothelial cells. Methods: In the present study, we evaluated the anti-inflammatory effects of Vaccariae hypaphorine (VH on lipopolysaccharide (LPS-challenged endothelial EA.hy926 cells. The inflammatory cytokines including tumor necrosis factor-α (TNF-α, interleukin-1β (IL-1β, monocyte chemoattractant protein 1 (MCP-1 and vascular cellular adhesion molecule-1 (VCAM-1 were measured by real-time PCR (RT-PCR. The expressions of adenosine monophosphate-activated protein kinase (AMPK, acetyl-CoA carboxylase (ACC, toll-like receptor 4 (TLR4, peroxisome proliferator-activated receptor γ (PPARγ were detected by Western blotting or immunofluorescence. Results: We showed that LPS stimulated the expressions of TNF-α, IL-1β, MCP-1, VCAM-1 and TLR4, but attenuated the phosphorylation of AMPK and ACC as well as PPARγ protein levels, which were reversed by VH pretreatment. Moreover, we observed that LPS-upregulated TLR4 protein expressions were inhibited by PPARγ agonist pioglitazone, and the downregulated PPARγ expressions in response to LPS were partially restored by knockdown of TLR4. The negative regulation loop between TLR4 and PPARγ response to LPS was modulated by AMPK agonist AICAR (5-Aminoimidazole-4-carboxamide riboside or acadesine or A769662. Conclusions: Taken together, our results suggested that VH ameliorated LPS-induced inflammatory cytokines production in endothelial cells via inhibition of TLR4 and activation of PPARγ, dependent on AMPK signalling pathway.

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.

Soya-cerebroside, an extract of Cordyceps militaris, suppresses monocyte migration and prevents cartilage degradation in inflammatory animal models

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Liu, Shan-Chi; Chiu, Ching-Peng; Tsai, Chun-Hao; Hung, Chun-Yin; Li, Te-Mao; Wu, Yang-Chang; Tang, Chih-Hsin

2017-01-01

Pathophysiological events that modulate the progression of structural changes in osteoarthritis (OA) include the secretion of inflammatory molecules, such as proinflammatory cytokines. Interleukin-1beta (IL-1β) is the prototypical inflammatory cytokine that activates OA synovial cells to release cytokines and chemokines in support of the inflammatory response. The monocyte chemoattractant protein-1 (MCP-1/CCL2) is one of the key chemokines that regulate migration and infiltration of monocytes in response to inflammation. We show in this study that IL-1β-induced MCP-1 expression and monocyte migration in OA synovial fibroblasts (OASFs) is effectively inhibited by soya-cerebroside, an extract of Cordyceps militaris. We found that soya-cerebroside up-regulated of microRNA (miR)-432 expression via inhibiting AMPK and AKT signaling pathways in OASFs. Soya-cerebroside also effectively decreased monocyte infiltration and prevented cartilage degradation in a rat inflammatory model. Our findings are the first to demonstrate that soya-cerebroside inhibits monocyte/macrophage infiltration into synoviocytes, attenuating synovial inflammation and preventing cartilage damage by reducing MCP-1 expression in vitro and in vivo. Taken together, we suggest a novel therapeutic strategy based on the use of soya-cerebroside for the management of OA. PMID:28225075

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.

Glycolipids from spinach suppress LPS-induced vascular inflammation through eNOS and NK-κB signaling.

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Ishii, Masakazu; Nakahara, Tatsuo; Araho, Daisuke; Murakami, Juri; Nishimura, Masahiro

2017-07-01

Glycolipids are the major constituent of the thylakoid membrane of higher plants and have a variety of biological and pharmacological activities. However, anti-inflammatory effects of glycolipids on vascular endothelial cells have not been elucidated. Here, we investigated the effect of glycolipids extracted from spinach on lipopolysaccharides (LPS)-induced endothelial inflammation and evaluated the underlying molecular mechanisms. Treatment with glycolipids from spinach had no cytotoxic effects on cultured human umbilical vein endothelial cells (HUVECs) and significantly blocked the expression of LPS-induced interleukin (IL)-6, monocyte chemoattractant protein-1 (MCP-1), vascular cell adhesion molecule-1 (VCAM-1), and intracellular adhesion molecule-1 (ICAM-1) in them. Glycolipids treatment also effectively suppressed monocyte adhesion to HUVECs. Treatment with glycolipids inhibited LPS-induced NF-κB phosphorylation and nuclear translocation. In addition, glycolipids treatment significantly promoted endothelial nitric oxide synthase (eNOS) activation and nitric oxide (NO) production in HUVECs. Furthermore, glycolipids treatment blocked LPS-induced inducible NOS (iNOS) expression in HUVECs. Pretreatment with a NOS inhibitor attenuated glycolipids-induced suppression of NF-κB activation and adhesion molecule expression, and abolished the glycolipids-mediated suppression of monocyte adhesion to HUVECs. These results indicate that glycolipids suppress LPS-induced vascular inflammation through attenuation of the NF-κB pathway by increasing NO production in endothelial cells. These findings suggest that glycolipids from spinach may have a potential therapeutic use for inflammatory vascular diseases. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Increased cerebrospinal fluid levels of cytokines monocyte chemoattractant protein-1 (MCP-1) and macrophage inflammatory protein-1β (MIP-1β) in patients with amyotrophic lateral sclerosis.

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Martínez, H R; Escamilla-Ocañas, C E; Camara-Lemarroy, C R; González-Garza, M T; Moreno-Cuevas, J; García Sarreón, M A

2017-10-10

Neuroinflammation has recently been described in amyotrophic lateral sclerosis (ALS). However, the precise role of such proinflammatory cytokines as monocyte chemoattractant protein-1 (MCP-1) and macrophage inflammatory protein-1β (MIP-1β) in ALS has not yet been determined. In this study, we determined cerebrospinal fluid (CSF) MCP-1 and MIP-1β levels and assessed their association with the duration and severity of ALS. Concentrations of MCP-1 and MIP-1β were determined in the CSF of 77 patients diagnosed with ALS and 13 controls. Cytokine levels were analysed in relation to ALS duration (12months) and severity (30points on the ALS Functional Rating Scale administered at hospital admission). Higher CSF MIP-1β (10.68pg/mL vs. 4.69pg/mL, P<.0001) and MCP-1 (234.89pg/mL vs. 160.95pg/mL, P=.011) levels were found in the 77 patients with ALS compared to controls. There were no differences in levels of either cytokine in relation to disease duration or severity. However, we did observe a significant positive correlation between MIP-1β and MCP-1 in patients with ALS. The increase in MIP-1β and MCP-1 levels suggests that these cytokines may have a synergistic effect on ALS pathogenesis. However, in our cohort, no association was found with either the duration or the clinical severity of the disease. Copyright © 2017 Sociedad Española de Neurología. Publicado por Elsevier España, S.L.U. All rights reserved.

Glutathione regulation of redox-sensitive signals in tumor necrosis factor-α-induced vascular endothelial dysfunction

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Tsou, T.-C.; Yeh, S.C.; Tsai, F.-Y.; Chen, J.-W.; Chiang, H.-C.

2007-01-01

We investigated the regulatory role of glutathione in tumor necrosis factor-alpha (TNF-α)-induced vascular endothelial dysfunction as evaluated by using vascular endothelial adhesion molecule expression and monocyte-endothelial monolayer binding. Since TNF-α induces various biological effects on vascular cells, TNF-α dosage could be a determinant factor directing vascular cells into different biological fates. Based on the adhesion molecule expression patterns responding to different TNF-α concentrations, we adopted the lower TNF-α (0.2 ng/ml) to rule out the possible involvement of other TNF-α-induced biological effects. Inhibition of glutathione synthesis by L-buthionine-(S,R)-sulfoximine (BSO) resulted in down-regulations of the TNF-α-induced adhesion molecule expression and monocyte-endothelial monolayer binding. BSO attenuated the TNF-α-induced nuclear factor-kappaB (NF-κB) activation, however, with no detectable effect on AP-1 and its related mitogen-activated protein kinases (MAPKs). Deletion of an AP-1 binding site in intercellular adhesion molecule-1 (ICAM-1) promoter totally abolished its constitutive promoter activity and its responsiveness to TNF-α. Inhibition of ERK, JNK, or NF-κB attenuates TNF-α-induced ICAM-1 promoter activation and monocyte-endothelial monolayer binding. Our study indicates that TNF-α induces adhesion molecule expression and monocyte-endothelial monolayer binding mainly via activation of NF-κB in a glutathione-sensitive manner. We also demonstrated that intracellular glutathione does not modulate the activation of MAPKs and/or their downstream AP-1 induced by lower TNF-α. Although AP-1 activation by the lower TNF-α was not detected in our systems, we could not rule out the possible involvement of transiently activated MAPKs/AP-1 in the regulation of TNF-α-induced adhesion molecule expression

Chronic Inhibition of PDE5 Limits Pro-Inflammatory Monocyte-Macrophage Polarization in Streptozotocin-Induced Diabetic Mice.

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Mary Anna Venneri

Full Text Available Diabetes mellitus is characterized by changes in endothelial cells that alter monocyte recruitment, increase classic (M1-type tissue macrophage infiltration and lead to self-sustained inflammation. Our and other groups recently showed that chronic inhibition of phosphodiesterase-5 (PDE5i affects circulating cytokine levels in patients with diabetes; whether PDE5i also affects circulating monocytes and tissue inflammatory cell infiltration remains to be established. Using murine streptozotocin (STZ-induced diabetes and in human vitro cell-cell adhesion models we show that chronic hyperglycemia induces changes in myeloid and endothelial cells that alter monocyte recruitment and lead to self-sustained inflammation. Continuous PDE5i with sildenafil (SILD expanded tissue anti-inflammatory TIE2-expressing monocytes (TEMs, which are known to limit inflammation and promote tissue repair. Specifically, SILD: 1 normalizes the frequency of circulating pro-inflammatory monocytes triggered by hyperglycemia (53.7 ± 7.9% of CD11b+Gr-1+ cells in STZ vs. 30.4 ± 8.3% in STZ+SILD and 27.1 ± 1.6% in CTRL, P<0.01; 2 prevents STZ-induced tissue inflammatory infiltration (4-fold increase in F4/80+ macrophages in diabetic vs. control mice by increasing renal and heart anti-inflammatory TEMs (30.9 ± 3.6% in STZ+SILD vs. 6.9 ± 2.7% in STZ, P <0.01, and 11.6 ± 2.9% in CTRL mice; 3 reduces vascular inflammatory proteins (iNOS, COX2, VCAM-1 promoting tissue protection; 4 lowers monocyte adhesion to human endothelial cells in vitro through the TIE2 receptor. All these changes occurred independently from changes of glycemic status. In summary, we demonstrate that circulating renal and cardiac TEMs are defective in chronic hyperglycemia and that SILD normalizes their levels by facilitating the shift from classic (M1-like to alternative (M2-like/TEM macrophage polarization. Restoration of tissue TEMs with PDE5i could represent an additional pharmacological tool to prevent

Mast cell chemotaxis – Chemoattractants and signaling pathways

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Ivana eHalova

2012-05-01

Full Text Available Migration of mast cells is essential for their recruitment within target tissues where they play an important role in innate and adaptive immune responses. These processes rely on the ability of mast cells to recognize appropriate chemotactic stimuli and react to them by a chemotactic response. Another level of intercellular communication is attained by production of chemoattractants by activated mast cells, which results in accumulation of mast cells and other hematopoietic cells at the sites of inflammation. Mast cells express numerous surface receptors for various ligands with properties of potent chemoattractants. They include the stem cell factor recognized by c-Kit, antigen, which binds to immunoglobulin E (IgE anchored to the high affinity IgE receptor (FcRI, highly cytokinergic IgE recognized by FcRI, lipid mediator sphingosine-1-phosphate (S1P, which binds to G-protein-coupled receptors (GPCRs. Other large groups of chemoattractants are eicosanoids [prostaglandin E2 and D2, leukotriene (LT B4, LTD4 and LTC4, and others] and chemokines (CC, CXC, C and CX3X, which also bind to various GPCRs. Further noteworthy chemoattractants are isoforms of transforming growth factor (TGF , which are sensitively recognized by TGF- serine/threonine type I and II  receptors, adenosine, C1q, C3a, and C5a components of the complement, 5-hydroxytryptamine, neuroendocrine peptide catestatin, interleukin-6, tumor necrosis factor- and others. Here we discuss the major types of chemoattractants recognized by mast cells, their target receptors, as well as signaling pathways they utilize. We also briefly deal with methods used for studies of mast cell chemotaxis and with ways of how these studies profited from the results obtained in other cellular systems.

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.

Monocyte Chemoattractant Protein-1 in the choroid plexus: a potential link between vascular pro-inflammatory mediators and the CNS during peripheral tissue inflammation

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Mitchell, K.; Yang, H.-Y. T.; Berk, J. D.; Tran, J. H.; Iadarola, M. J.

2009-01-01

During peripheral tissue inflammation, inflammatory processes in the CNS can be initiated by blood-borne pro-inflammatory mediators. The choroid plexus, the site of CSF production, is a highly specialized interface between the vascular system and CNS, and thus, this structure may be an important element in communication between the vascular compartment and the CNS during peripheral tissue inflammation. We investigated the potential participation of the choroid plexus in this process during peripheral tissue inflammation by examining expression of the SCYA2 gene which codes for monocyte chemoattractant protein-1 (MCP-1). MCP-1 protein was previously reported to be induced in a variety of cells during peripheral tissue inflammation. In the basal state, SCYA2 is highly expressed in the choroid plexus as compared to other CNS tissues. During hind paw inflammation, SCYA2 expression was significantly elevated in choroid plexus, whereas it remained unchanged in a variety of brain regions. The SCYA2-expressing cells were strongly associated with the choroid plexus as vascular depletion of blood cells by whole-body saline flush did not significantly alter SCYA2 expression in the choroid plexus. In situ hybridization suggested that the SCYA2-expressing cells were localized to the choroid plexus stroma. To elucidate potential molecular mechanisms of SCYA2 increase, we examined genes in the NF-κβ signaling cascade including TNF-α, IL-1β and IκBα in choroid tissue. Given that we also detected increased levels of MCP-1 protein by ELISA, we sought to identify potential downstream targets of MCP-1 and observed altered expression levels of mRNAs encoding tight junction proteins TJP2 and claudin 5. Finally, we detected a substantial up-regulation of the transcript encoding E-selectin, a molecule which could participate in leukocyte recruitment to the choroid plexus along with MCP-1. Together, these results suggest that profound changes occur in the choroid plexus during

Loss of PPAR gamma in immune cells impairs the ability of abscisic acid to improve insulin sensitivity by suppressing monocyte chemoattractant protein-1 expression and macrophage infiltration into white adipose tissue.

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Guri, Amir J; Hontecillas, Raquel; Ferrer, Gerardo; Casagran, Oriol; Wankhade, Umesh; Noble, Alexis M; Eizirik, Decio L; Ortis, Fernanda; Cnop, Miriam; Liu, Dongmin; Si, Hongwei; Bassaganya-Riera, Josep

2008-04-01

Abscisic acid (ABA) is a natural phytohormone and peroxisome proliferator-activated receptor gamma (PPARgamma) agonist that significantly improves insulin sensitivity in db/db mice. Although it has become clear that obesity is associated with macrophage infiltration into white adipose tissue (WAT), the phenotype of adipose tissue macrophages (ATMs) and the mechanisms by which insulin-sensitizing compounds modulate their infiltration remain unknown. We used a loss-of-function approach to investigate whether ABA ameliorates insulin resistance through a mechanism dependent on immune cell PPARgamma. We characterized two phenotypically distinct ATM subsets in db/db mice based on their surface expression of F4/80. F4/80(hi) ATMs were more abundant and expressed greater concentrations of chemokine receptor (CCR) 2 and CCR5 when compared to F4/80(lo) ATMs. ABA significantly decreased CCR2(+) F4/80(hi) infiltration into WAT and suppressed monocyte chemoattractant protein-1 (MCP-1) expression in WAT and plasma. Furthermore, the deficiency of PPARgamma in immune cells, including macrophages, impaired the ability of ABA to suppress the infiltration of F4/80(hi) ATMs into WAT, to repress WAT MCP-1 expression and to improve glucose tolerance. We provide molecular evidence in vivo demonstrating that ABA improves insulin sensitivity and obesity-related inflammation by inhibiting MCP-1 expression and F4/80(hi) ATM infiltration through a PPARgamma-dependent mechanism.

Cigarette smoke extract counteracts atheroprotective effects of high laminar flow on endothelial function

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Sindy Giebe

2017-08-01

Full Text Available Tobacco smoking and hemodynamic forces are key stimuli in the development of endothelial dysfunction and atherosclerosis. High laminar flow has an atheroprotective effect on the endothelium and leads to a reduced response of endothelial cells to cardiovascular risk factors compared to regions with disturbed or low laminar flow. We hypothesize that the atheroprotective effect of high laminar flow could delay the development of endothelial dysfunction caused by cigarette smoking. Primary human endothelial cells were stimulated with increasing dosages of aqueous cigarette smoke extract (CSEaq. CSEaq reduced cell viability in a dose-dependent manner. The main mediator of cellular adaption to oxidative stress, nuclear factor erythroid 2-related factor 2 (NRF2 and its target genes heme oxygenase (decycling 1 (HMOX1 or NAD(PH quinone dehydrogenase 1 (NQO1 were strongly increased by CSEaq in a dose-dependent manner. High laminar flow induced elongation of endothelial cells in the direction of flow, activated the AKT/eNOS pathway, increased eNOS expression, phosphorylation and NO release. These increases were inhibited by CSEaq. Pro-inflammatory adhesion molecules intercellular adhesion molecule-1 (ICAM1, vascular cell adhesion molecule-1 (VCAM1, selectin E (SELE and chemokine (C-C motif ligand 2 (CCL2/MCP-1 were increased by CSEaq. Low laminar flow induced VCAM1 and SELE compared to high laminar flow. High laminar flow improved endothelial wound healing. This protective effect was inhibited by CSEaq in a dose-dependent manner through the AKT/eNOS pathway. Low as well as high laminar flow decreased adhesion of monocytes to endothelial cells. Whereas, monocyte adhesion was increased by CSEaq under low laminar flow, this was not evident under high laminar flow.This study shows the activation of major atherosclerotic key parameters by CSEaq. Within this process, high laminar flow is likely to reduce the harmful effects of CSEaq to a certain degree. The

Effect of tributyltin on mammalian endothelial cell integrity.

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Botelho, G; Bernardini, C; Zannoni, A; Ventrella, V; Bacci, M L; Forni, M

2015-01-01

Tributyltin (TBT), is a man-made pollutants, known to accumulate along the food chain, acting as an endocrine disruptor in marine organisms, with toxic and adverse effects in many tissues including vascular system. Based on the absence of specific studies of TBT effects on endothelial cells, we aimed to evaluate the toxicity of TBT on primary culture of porcine aortic endothelial cells (pAECs), pig being an excellent model to study human cardiovascular disease. pAECs were exposed for 24h to TBT (100, 250, 500, 750 and 1000nM) showing a dose dependent decrease in cell viability through both apoptosis and necrosis. Moreover the ability of TBT (100 and 500nM) to influence endothelial gene expression was investigated at 1, 7 and 15h of treatment. Gene expression of tight junction molecules, occludin (OCLN) and tight junction protein-1 (ZO-1) was reduced while monocyte adhesion and adhesion molecules ICAM-1 and VCAM-1 (intercellular adhesion molecule-1 and vascular cell adhesion molecule-1) levels increased significantly at 1h. IL-6 and estrogen receptors 1 and 2 (ESR-1 and ESR-2) mRNAs, after a transient decrease, reached the maximum levels after 15h of exposure. Finally, we demonstrated that TBT altered endothelial functionality greatly increasing monocyte adhesion. These findings indicate that TBT deeply alters endothelial profile, disrupting their structure and interfering with their ability to interact with molecules and other cells. Copyright © 2015 Elsevier Inc. All rights reserved.

Monocytes infiltrate the pancreas via the MCP-1/CCR2 pathway and differentiate into stellate cells.

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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

Inhibition of tumor necrosis factor-α-induced expression of adhesion molecules in human endothelial cells by the saponins derived from roots of Platycodon grandiflorum

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Kim, Ji Young; Kim, Dong Hee; Kim, Hyung Gyun; Song, Gyu-Yong; Chung, Young Chul; Roh, Seong Hwan; Jeong, Hye Gwang

2006-01-01

Adhesion molecules play an important role in the development of atherogenesis and are produced by endothelial cells after being stimulated with various inflammatory cytokines. This study examined the effect of saponins that were isolated from the roots of Platycodon grandiflorum A. DC (Campanulaceae), Changkil saponins (CKS), on the cytokine-induced monocyte/human endothelial cell interaction, which is a crucial early event in atherogenesis. CKS significantly inhibited the TNFα-induced increase in monocyte adhesion to endothelial cells as well as decreased the protein and mRNA expression levels of vascular adhesion molecule-1 and intercellular cell adhesion molecule-1 on endothelial cells. Furthermore, CKS significantly inhibited the TNFα-induced production of intracellular reactive oxygen species (ROS) and activation of NF-κB by preventing IκB degradation and inhibiting IκB kinase activity. Overall, CKS has anti-atherosclerotic and anti-inflammatory activity, which is least in part the result of it reducing the cytokine-induced endothelial adhesion to monocytes by inhibiting intracellular ROS production, NF-κB activation, and cell adhesion molecule expression in endothelial cells

Chronic Inhibition of PDE5 Limits Pro-Inflammatory Monocyte-Macrophage Polarization in Streptozotocin-Induced Diabetic Mice.

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Venneri, Mary Anna; Giannetta, Elisa; Panio, Giuseppe; De Gaetano, Rita; Gianfrilli, Daniele; Pofi, Riccardo; Masciarelli, Silvia; Fazi, Francesco; Pellegrini, Manuela; Lenzi, Andrea; Naro, Fabio; Isidori, Andrea M

2015-01-01

Diabetes mellitus is characterized by changes in endothelial cells that alter monocyte recruitment, increase classic (M1-type) tissue macrophage infiltration and lead to self-sustained inflammation. Our and other groups recently showed that chronic inhibition of phosphodiesterase-5 (PDE5i) affects circulating cytokine levels in patients with diabetes; whether PDE5i also affects circulating monocytes and tissue inflammatory cell infiltration remains to be established. Using murine streptozotocin (STZ)-induced diabetes and in human vitro cell-cell adhesion models we show that chronic hyperglycemia induces changes in myeloid and endothelial cells that alter monocyte recruitment and lead to self-sustained inflammation. Continuous PDE5i with sildenafil (SILD) expanded tissue anti-inflammatory TIE2-expressing monocytes (TEMs), which are known to limit inflammation and promote tissue repair. Specifically, SILD: 1) normalizes the frequency of circulating pro-inflammatory monocytes triggered by hyperglycemia (53.7 ± 7.9% of CD11b+Gr-1+ cells in STZ vs. 30.4 ± 8.3% in STZ+SILD and 27.1 ± 1.6% in CTRL, PTEMs (30.9 ± 3.6% in STZ+SILD vs. 6.9 ± 2.7% in STZ, P TEMs are defective in chronic hyperglycemia and that SILD normalizes their levels by facilitating the shift from classic (M1-like) to alternative (M2-like)/TEM macrophage polarization. Restoration of tissue TEMs with PDE5i could represent an additional pharmacological tool to prevent end-organ diabetic complications.

Insulin regulates multiple signaling pathways leading to monocyte/macrophage chemotaxis into the wound tissue

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Yan Liu

2018-01-01

Full Text Available Wound healing is a complex process that involves sequential phases that overlap in time and space and affect each other dynamically at the gene and protein levels. We previously showed that insulin accelerates wound healing by stimulating faster and regenerative healing. One of the processes that insulin stimulates is an increase in monocyte/macrophage chemotaxis. In this study, we performed experiments in vivo and in vitro to elucidate the signaling transduction pathways that are involved in insulin-induced monocyte/macrophage chemotaxis. We found that insulin stimulates THP-1 cell chemotaxis in a dose-dependent and insulin receptor-dependent manner. We also show that the kinases PI3K-Akt, SPAK/JNK, and p38 MAPK are key molecules in the insulin-induced signaling pathways that lead to chemoattraction of the THP-1 cell. Furthermore, both PI3K-Akt and SPAK/JNK signaling involve Rac1 activation, an important molecule in regulating cell motility. Indeed, topical application of Rac1 inhibitor at an early stage during the healing process caused delayed and impaired healing even in the presence of insulin. These results delineate cell and molecular mechanisms involved in insulin-induced chemotaxis of monocyte/macrophage, cells that are critical for proper healing.

A novel adipocytokine, chemerin exerts anti-inflammatory roles in human vascular endothelial cells

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Yamawaki, Hideyuki, E-mail: yamawaki@vmas.kitasato-u.ac.jp [Laboratory of Veterinary Pharmacology, School of Veterinary Medicine, Kitasato University, Aomori 034-8628 (Japan); Kameshima, Satoshi; Usui, Tatsuya; Okada, Muneyoshi; Hara, Yukio [Laboratory of Veterinary Pharmacology, School of Veterinary Medicine, Kitasato University, Aomori 034-8628 (Japan)

2012-06-22

Highlights: Black-Right-Pointing-Pointer Chemerin is a novel adipocytokine with almost unknown function in vasculature. Black-Right-Pointing-Pointer Chemerin activates Akt/eNOS/NO pathways in endothelial cells. Black-Right-Pointing-Pointer Chemerin inhibits TNF-{alpha}-induced monocyte adhesion to endothelial cells. Black-Right-Pointing-Pointer Chemerin inhibits TNF-induced VCAM-1 via suppressing NF-{kappa}B and p38 signal. Black-Right-Pointing-Pointer Chemerin is anti-inflammatory through producing NO in vascular endothelium. -- Abstract: Chemerin is a recently identified adipocytokine which plays a role on inflammation and adipocytes metabolism. However, its function in vasculature is largely unknown. We examined the effects of chemerin on vascular endothelial inflammatory states. Treatment of human umbilical vein endothelial cells with chemerin (300 ng/ml, 20 min) induced phosphorylation of Akt (Ser473) and endothelial nitric oxide (NO) synthase (eNOS) (Ser1177). Consistently, chemerin increased intracellular cyclic GMP content. Pretreatment with chemerin (1-300 ng/ml, 24 h) significantly inhibited phosphorylation of nuclear factor (NF)-{kappa}B p65 (Ser536) and p38 as well as vascular cell adhesion molecule (VCAM)-1 expression induced by tumor necrosis factor (TNF)-{alpha} (5 ng/ml, 20 min-6 h). Inhibitor of NF-{kappa}B or p38 significantly inhibited the TNF-{alpha}-induced VCAM-1 expression. Chemerin also inhibited TNF-{alpha}-induced VCAM-1 expression in rat isolated aorta. Moreover, chemerin significantly inhibited monocytes adhesion to TNF-{alpha}-stimulated endothelial cells. The inhibitory effect of chemerin on TNF-{alpha}-induced VCAM-1 was reversed by a NOS inhibitor. Conversely, an NO donor, sodium nitroprusside significantly inhibited TNF-{alpha}-induced VCAM-1. The present results for the first time demonstrate that chemerin plays anti-inflammatory roles by preventing TNF-{alpha}-induced VCAM-1 expression and monocytes adhesion in vascular

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.

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.

In situ tissue regeneration: chemoattractants for endogenous stem cell recruitment.

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Vanden Berg-Foels, Wendy S

2014-02-01

Tissue engineering uses cells, signaling molecules, and/or biomaterials to regenerate injured or diseased tissues. Ex vivo expanded mesenchymal stem cells (MSC) have long been a cornerstone of regeneration therapies; however, drawbacks that include altered signaling responses and reduced homing capacity have prompted investigation of regeneration based on endogenous MSC recruitment. Recent successful proof-of-concept studies have further motivated endogenous MSC recruitment-based approaches. Stem cell migration is required for morphogenesis and organogenesis during development and for tissue maintenance and injury repair in adults. A biomimetic approach to in situ tissue regeneration by endogenous MSC requires the orchestration of three main stages: MSC recruitment, MSC differentiation, and neotissue maturation. The first stage must result in recruitment of a sufficient number of MSC, capable of effecting regeneration, to the injured or diseased tissue. One of the challenges for engineering endogenous MSC recruitment is the selection of effective chemoattractant(s). The objective of this review is to synthesize and evaluate evidence of recruitment efficacy by reported chemoattractants, including growth factors, chemokines, and other more recently appreciated MSC chemoattractants. The influence of MSC tissue sources, cell culture methods, and the in vitro and in vivo environments is discussed. This growing body of knowledge will serve as a basis for the rational design of regenerative therapies based on endogenous MSC recruitment. Successful endogenous MSC recruitment is the first step of successful tissue regeneration.

Active spice-derived components can inhibit inflammatory responses of adipose tissue in obesity by suppressing inflammatory actions of macrophages and release of monocyte chemoattractant protein-1 from adipocytes.

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Woo, Hae-Mi; Kang, Ji-Hye; Kawada, Teruo; Yoo, Hoon; Sung, Mi-Kyung; Yu, Rina

2007-02-13

Inflammation plays a key role in obesity-related pathologies such as cardiovascular disease, type II diabetes, and several types of cancer. Obesity-induced inflammation entails the enhancement of the recruitment of macrophages into adipose tissue and the release of various proinflammatory proteins from fat tissue. Therefore, the modulation of inflammatory responses in obesity may be useful for preventing or ameliorating obesity-related pathologies. Some spice-derived components, which are naturally occurring phytochemicals, elicit antiobesity and antiinflammatory properties. In this study, we investigated whether active spice-derived components can be applied to the suppression of obesity-induced inflammatory responses. Mesenteric adipose tissue was isolated from obese mice fed a high-fat diet and cultured to prepare an adipose tissue-conditioned medium. Raw 264.7 macrophages were treated with the adipose tissue-conditioned medium with or without active spice-derived components (i.e., diallyl disulfide, allyl isothiocyanate, piperine, zingerone and curcumin). Chemotaxis assay was performed to measure the degree of macrophage migration. Macrophage activation was estimated by measuring tumor necrosis factor-alpha (TNF-alpha), nitric oxide, and monocyte chemoattractant protein-1 (MCP-1) concentrations. The active spice-derived components markedly suppressed the migration of macrophages induced by the mesenteric adipose tissue-conditioned medium in a dose-dependent manner. Among the active spice-derived components studied, allyl isothiocyanate, zingerone, and curcumin significantly inhibited the cellular production of proinflammatory mediators such as TNF-alpha and nitric oxide, and significantly inhibited the release of MCP-1 from 3T3-L1 adipocytes. Our findings suggest that the spice-derived components can suppress obesity-induced inflammatory responses by suppressing adipose tissue macrophage accumulation or activation and inhibiting MCP-1 release from adipocytes

Pertussis Toxin Exploits Host Cell Signaling Pathways Induced by Meningitis-Causing E. coli K1-RS218 and Enhances Adherence of Monocytic THP-1 Cells to Human Cerebral Endothelial Cells

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Laura Julia Starost

2016-10-01

Full Text Available Pertussis toxin (PTx, the major virulence factor of the whooping cough-causing bacterial pathogen Bordetella pertussis, permeabilizes the blood–brain barrier (BBB in vitro and in vivo. Breaking barriers might promote translocation of meningitis-causing bacteria across the BBB, thereby facilitating infection. PTx activates several host cell signaling pathways exploited by the neonatal meningitis-causing Escherichia coli K1-RS218 for invasion and translocation across the BBB. Here, we investigated whether PTx and E. coli K1-RS218 exert similar effects on MAPK p38, NF-κB activation and transcription of downstream targets in human cerebral endothelial TY10 cells using qRT-PCR, Western blotting, and ELISA in combination with specific inhibitors. PTx and E. coli K1-RS218 activate MAPK p38, but only E. coli K1-RS218 activates the NF-κB pathway. mRNA and protein levels of p38 and NF-κB downstream targets including IL-6, IL-8, CxCL-1, CxCL-2 and ICAM-1 were increased. The p38 specific inhibitor SB203590 blocked PTx-enhanced activity, whereas E. coli K1-RS218’s effects were inhibited by the NF-κB inhibitor Bay 11-7082. Further, we found that PTx enhances the adherence of human monocytic THP-1 cells to human cerebral endothelial TY10 cells, thereby contributing to enhanced translocation. These modulations of host cell signaling pathways by PTx and meningitis-causing E. coli support their contributions to pathogen and monocytic THP-1 cells translocation across the BBB.

The coffee diterpene kahweol inhibits tumor necrosis factor-α-induced expression of cell adhesion molecules in human endothelial cells

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Kim, Hyung Gyun; Kim, Ji Young; Hwang, Yong Pil; Lee, Kyung Jin; Lee, Kwang Youl; Kim, Dong Hee; Kim, Dong Hyun; Jeong, Hye Gwang

2006-01-01

Endothelial cells produce adhesion molecules after being stimulated with various inflammatory cytokines. These adhesion molecules play an important role in the development of atherogenesis. Recent studies have highlighted the chemoprotective and anti-inflammatory effects of kahweol, a coffee-specific diterpene. This study examined the effects of kahweol on the cytokine-induced monocyte/human endothelial cell interaction, which is a crucial early event in atherogenesis. Kahweol inhibited the adhesion of TNFα-induced monocytes to endothelial cells and suppressed the TNFα-induced protein and mRNA expression of the cell adhesion molecules, VCAM-1 and ICAM-1. Furthermore, kahweol inhibited the TNFα-induced JAK2-PI3K/Akt-NF-κB activation pathway in these cells. Overall, kahweol has anti-inflammatory and anti-atherosclerotic activities, which occurs partly by down-regulating the pathway that affects the expression and interaction of the cell adhesion molecules on endothelial cells

Can TIE-2 expressing monocytes represent a novel marker for hepatocellular carcinoma?

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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.

Polychlorinated biphenyl-induced VCAM-1 expression is attenuated in aortic endothelial cells isolated from caveolin-1 deficient mice

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Han, Sung Gu; Eum, Sung Yong; Toborek, Michal; Smart, Eric; Hennig, Bernhard

2010-01-01

Exposure to environmental contaminants, such as polychlorinated biphenyls (PCBs), is a risk factor for the development of cardiovascular diseases such as atherosclerosis. Vascular cell adhesion molecule-1 (VCAM-1) is a critical mediator for adhesion and uptake of monocytes across the endothelium in the early stages of atherosclerosis development. The upregulation of VCAM-1 by PCBs may be dependent on functional membrane domains called caveolae. Caveolae are particularly abundant in endothelial cell membranes and involved in trafficking and signal transduction. The objective of this study was to investigate the role of caveolae in PCB-induced endothelial cell dysfunction. Primary mouse aortic endothelial cells (MAECs) isolated from caveolin-1-deficient mice and background C57BL/6 mice were treated with coplanar PCBs, such as PCB77 and PCB126. In addition, siRNA gene silencing technique was used to knockdown caveolin-1 in porcine vascular endothelial cells. In MAECs with functional caveolae, VCAM-1 protein levels were increased after exposure to both coplanar PCBs, whereas expression levels of VCAM-1 were not significantly altered in cells deficient of caveolin-1. Furthermore, PCB-induced monocyte adhesion was attenuated in caveolin-1-deficient MAECs. Similarly, siRNA silencing of caveolin-1 in porcine endothelial cells confirmed the caveolin-1-dependent VCAM-1 expression. Treatment of cells with PCB77 and PCB126 resulted in phosphorylation of extracellular signal-regulated kinase-1/2 (ERK1/2), and pharmacological inhibition of ERK1/2 diminished the observed PCB-induced increase in monocyte adhesion. These findings suggest that coplanar PCBs induce adhesion molecule expression, such as VCAM-1, in endothelial cells, and that this response is regulated by caveolin-1 and functional caveolae. Our data demonstrate a critical role of functional caveolae in the activation and dysfunction of endothelial cells by coplanar PCBs.

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

Gut Microbiota in Type 2 Diabetes Individuals and Correlation with Monocyte Chemoattractant Protein1 and Interferon Gamma from Patients Attending a Tertiary Care Centre in Chennai, India

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Premalatha Pushpanathan

2016-01-01

Full Text Available Background: Type 2 diabetes mellitus (T2DM and obesity are associated with changes in gut microbiota and characterized by chronic low-grade inflammation. Monocyte chemoattractant protein-1 (MCP-1 and interferon gamma (IFNγ are proinflammatory cytokines which play an important role in the development of T2DM. We undertook this study to analyze the gut microbiota of T2DM and nondiabetic subjects and to determine the profile of MCP 1 and IFNγ in the same subjects attending a tertiary care center in Chennai, Tamil Nadu, India. Methods: The study included 30 subjects with clinical details. Stool and blood samples were collected from all the subjects. DNA was extracted from fecal samples and polymerase chain reaction was done using fusion primers. Metagenomic analysis was performed using ion torrent sequencing. The reads obtained were in FASTA format and reported as operational taxonomic units. Human MCP 1 and IFNγ enzyme linked immunosorbent assay (ELISA were performed for 23 serum samples. Results: The study consisted of 30 subjects; 17 were T2DM and 13 were nondiabetics. The gut microbiota among T2DM consisted predominantly of Gram negative bacteria; Escherichia and Prevotella, when compared with the nondiabetic group with predominantly Gram positive organisms suchas Faecalibacterium, Eubacterium, and Bifidobacterium. The mean MCP-1 values in the diabetic group were 232.8 pg/ml and in the nondiabetic group 170.84 pg/ml. IFNγ (mean 385.5 pg/ml was raised in glycated hemoglobin (HbA1c group of 6.5–7.5% which was statistically significant. Association of Escherichia with T2DM and association of Bifidobacteria in the nondiabetics were also statistically significant. Conclusion: Escherichia counts were elevated in T2DM with HbA1c of 6.5–8.5% which was statistically significant suggesting that lipopolysaccharides present in the cell wall of Gram-negative bacteria may be responsible for low-grade inflammation as evidenced by elevated MCP-1 and

Monocyte chemoattractant protein-1 (MCP-1 regulates macrophage cytotoxicity in abdominal aortic aneurysm.

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Qiwei Wang

Full Text Available AIMS: In abdominal aortic aneurysm (AAA, macrophages are detected in the proximity of aortic smooth muscle cells (SMCs. We have previously demonstrated in a murine model of AAA that apoptotic SMCs attract monocytes and other leukocytes by producing MCP-1. Here we tested whether infiltrating macrophages also directly contribute to SMC apoptosis. METHODS AND RESULTS: Using a SMC/RAW264.7 macrophage co-culture system, we demonstrated that MCP-1-primed RAWs caused a significantly higher level of apoptosis in SMCs as compared to control macrophages. Next, we detected an enhanced Fas ligand (FasL mRNA level and membrane FasL protein expression in MCP-1-primed RAWs. Neutralizing FasL blocked SMC apoptosis in the co-culture. In situ proximity ligation assay showed that SMCs exposed to primed macrophages contained higher levels of receptor interacting protein-1 (RIP1/Caspase 8 containing cell death complexes. Silencing RIP1 conferred apoptosis resistance to SMCs. In the mouse elastase injury model of aneurysm, aneurysm induction increased the level of RIP1/Caspase 8 containing complexes in medial SMCs. Moreover, TUNEL-positive SMCs in aneurysmal tissues were frequently surrounded by CD68(+/FasL(+ macrophages. Conversely, elastase-treated arteries from MCP-1 knockout mice display a reduction of both macrophage infiltration and FasL expression, which was accompanied by diminished apoptosis of SMCs. CONCLUSION: Our data suggest that MCP-1-primed macrophages are more cytotoxic. MCP-1 appears to modulate macrophage cytotoxicity by increasing the level of membrane bound FasL. Thus, we showed that MCP-1-primed macrophages kill SMCs through a FasL/Fas-Caspase8-RIP1 mediated mechanism.

Elongated membrane tethers, individually anchored by high affinity α4β1/VCAM-1 complexes, are the quantal units of monocyte arrests.

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Calvin Chu

Full Text Available The α4β1 integrin facilitates both monocyte rolling and adhesion to the vascular endothelium and is physiologically activated by monocyte chemoattractant protein (MCP-1. The current study investigated the initial events in the adhesion of THP-1 cells to immobilized Vascular Cell Adhesion Molecule 1 (VCAM-1. Using AFM force measurements, cell adhesion was shown to be mediated by two populations of α4β1/VCAM-1 complexes. A low affinity form of α4β1 was anchored to the elastic elements of the cytoskeleton, while a higher affinity conformer was coupled to the viscous elements of the cell membrane. Within 100 ms of contact, THP-1 cells, stimulated by co-immobilized MCP-1, exhibited a tremendous increase in adhesion to VCAM-1. Enhanced cell adhesion was accompanied by a local decoupling of the cell membrane from the cytoskeleton and the formation of long membrane tethers. The tethers were individually anchored by multiple α4β1/VCAM-1 complexes that prolonged the extension of the viscous tethers. In vivo, the formation of these membrane tethers may provide the quantal structural units for the arrest of rolling monocytes within the blood vessels.

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.

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.

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.

Arachidonic acid is a chemoattractant for Dictyostelium discoideum

Indian Academy of Sciences (India)

Arachidonic acid is a chemoattractant for Dictyostelium discoideum cells ... Arachidonic acid; chemotaxis; fatty acids; iplA ... Previously, we have shown that arachidonic acid (AA) induces an increase in the cytosolic Ca2+ concentration by causing the release of Ca2+ from intracellular stores and activating influx of ...

Equine Herpesvirus Type 1 Enhances Viral Replication in CD172a+ Monocytic Cells upon Adhesion to Endothelial Cells.

Science.gov (United States)

Laval, Kathlyn; Favoreel, Herman W; Poelaert, Katrien C K; Van Cleemput, Jolien; Nauwynck, Hans J

2015-11-01

Equine herpesvirus type 1 (EHV-1) is a main cause of respiratory disease, abortion, and encephalomyelopathy in horses. Monocytic cells (CD172a(+)) are the main carrier cells of EHV-1 during primary infection and are proposed to serve as a "Trojan horse" to facilitate the dissemination of EHV-1 to target organs. However, the mechanism by which EHV-1 is transferred from CD172a(+) cells to endothelial cells (EC) remains unclear. The aim of this study was to investigate EHV-1 transmission between these two cell types. We hypothesized that EHV-1 employs specific strategies to promote the adhesion of infected CD172a(+) cells to EC to facilitate EHV-1 spread. Here, we demonstrated that EHV-1 infection of CD172a(+) cells resulted in a 3- to 5-fold increase in adhesion to EC. Antibody blocking experiments indicated that α4β1, αLβ2, and αVβ3 integrins mediated adhesion of infected CD172a(+) cells to EC. We showed that integrin-mediated phosphatidylinositol 3-kinase (PI3K) and ERK/MAPK signaling pathways were involved in EHV-1-induced CD172a(+) cell adhesion at early times of infection. EHV-1 replication was enhanced in adherent CD172a(+) cells, which correlates with the production of tumor necrosis factor alpha (TNF-α). In the presence of neutralizing antibodies, approximately 20% of infected CD172a(+) cells transferred cytoplasmic material to uninfected EC and 0.01% of infected CD172a(+) cells transmitted infectious virus to neighboring cells. Our results demonstrated that EHV-1 infection induces adhesion of CD172a(+) cells to EC, which enhances viral replication, but that transfer of viral material from CD172a(+) cells to EC is a very specific and rare event. These findings give new insights into the complex pathogenesis of EHV-1. Equine herpesvirus type 1 (EHV-1) is a highly prevalent pathogen worldwide, causing frequent outbreaks of abortion and myeloencephalopathy, even in vaccinated horses. After primary replication in the respiratory tract, EHV-1 disseminates

Anti-TNF-α activity of Portulaca oleracea in vascular endothelial cells.

Science.gov (United States)

Lee, An Sook; Kim, Jin Sook; Lee, Yun Jung; Kang, Dae Gill; Lee, Ho Sub

2012-01-01

Vascular inflammation plays a key role in the pathogenesis and progression of atherosclerosis, a main complication of diabetes. The present study investigated whether an aqueous extract of Portulaca oleracea (AP) prevents the TNF-α-induced vascular inflammatory process in the human umbilical vein endothelial cell (HUVEC). The stimulation of TNF-α induced overexpression of adhesion molecules affects vascular cell adhesion molecule (VCAM)-1, intercellular adhesion molecule (ICAM)-1 and E-selectin for example. However, AP significantly suppressed TNF-α-induced over-expression of these adhesion molecules in a dose-dependent manner. In addition, pretreatment with AP dose-dependently reduced an increase of the adhesion of HL-60 cells to TNF-α-induced HUVEC. Furthermore, we observed that stimulation of TNF-α significantly increased intracellular reactive oxygen species (ROS) production. However, pretreatment with AP markedly blocked TNF-α-induced ROS production in a dose-dependent manner. The western blot and immunofluorescence analysis showed that AP inhibited the translocation of p65 NF-κB to the nucleus. In addition, AP suppressed the TNF-α-induced degradation of IκB-α and attenuated the TNF-α-induced NF-κB binding. AP also effectively reduced TNF-α-induced mRNA expressions of monocyte chemoattractant protein (MCP)-1 and interleukin (IL)-8 in a dose-dependent manner. Taken together, AP prevents the vascular inflammatory process through the inhibition of intracellular ROS production and NF-κB activation as well as the reduction of adhesion molecule expression in TNF-α-induced HUVEC. These results suggested that AP might have a potential therapeutic effect by inhibiting the vascular inflammation process in vascular diseases such as atherosclerosis.

Chemoattraction of Ichthyophthirius multifiliis (Ciliophora) theronts to host molecules

DEFF Research Database (Denmark)

Buchmann, Kurt; Nielsen, Michael Engelbrecht

1999-01-01

not attract theronts. In contrast, sera and mucus from a range of teleosts (including marine fish) were effective attractants. Fractionation by gel filtration of fish serum allowed determination of the molecular size of the attracting proteins. Further biochemical studies suggested the chemoattractants...

Dual mechanisms of NF-κB inhibition in carnosol-treated endothelial cells

International Nuclear Information System (INIS)

Lian, K.-C.; Chuang, J.-J.; Hsieh, C.-W.; Wung, B.-S.; Huang, G.-D.; Jian, T.-Y.; Sun, Y.-W.

2010-01-01

The increased adhesion of monocytes to injured endothelial layers is a critical early event in atherogenesis. Under inflammatory conditions, there is increased expression of specific cell adhesion molecules on activated vascular endothelial cells, which increases monocyte adhesion. In our current study, we demonstrate a putative mechanism for the anti-inflammatory effects of carnosol, a diterpene derived from the herb rosemary. Our results show that both carnosol and rosemary essential oils inhibit the adhesion of TNFα-induced monocytes to endothelial cells and suppress the expression of ICAM-1 at the transcriptional level. Moreover, carnosol was found to exert its inhibitory effects by blocking the degradation of the inhibitory protein IκBα in short term pretreatments but not in 12 h pretreatments. Our data show that carnosol reduces IKK-β phosphorylation in pretreatments of less than 3 h. In TNFα-treated ECs, NF-κB nuclear translocation and transcriptional activity was abolished by up to 12 h of carnosol pretreatment and this was blocked by Nrf-2 siRNA. The long-term inhibitory effects of carnosol thus appear to be mediated through its induction of Nrf-2-related genes. The inhibition of ICAM-1 expression and p65 translocation is reversed by HO-1 siRNA. Carnosol also upregulates the Nrf-2-related glutathione synthase gene and thereby increases the GSH levels after 9 h of exposure. Treating ECs with a GSH synthesis inhibitor, BSO, blocks the inhibitory effects of carnosol. In addition, carnosol increases p65 glutathionylation. Hence, our present findings indicate that carnosol suppresses TNFα-induced singling pathways through the inhibition of IKK-β activity or the upregulation of HO-1 expression. The resulting GSH levels are dependent, however, on the length of the carnosol pretreatment period.

Omega-3 fatty acid oxidation products prevent vascular endothelial cell activation by coplanar polychlorinated biphenyls

International Nuclear Information System (INIS)

Majkova, Zuzana; Layne, Joseph; Sunkara, Manjula; Morris, Andrew J.; Toborek, Michal; Hennig, Bernhard

2011-01-01

Coplanar polychlorinated biphenyls (PCBs) may facilitate development of atherosclerosis by stimulating pro-inflammatory pathways in the vascular endothelium. Nutrition, including fish oil-derived long-chain omega-3 fatty acids, such as docosahexaenoic acid (DHA, 22:6ω-3), can reduce inflammation and thus the risk of atherosclerosis. We tested the hypothesis that cyclopentenone metabolites produced by oxidation of DHA can protect against PCB-induced endothelial cell dysfunction. Oxidized DHA (oxDHA) was prepared by incubation of the fatty acid with the free radical generator 2,2-azo-bis(2-amidinopropane) dihydrochloride (AAPH). Cellular pretreatment with oxDHA prevented production of superoxide induced by PCB77, and subsequent activation of nuclear factor-κB (NF-κB). A 4 /J 4 -neuroprostanes (NPs) were identified and quantitated using HPLC ESI tandem mass spectrometry. Levels of these NPs were markedly increased after DHA oxidation with AAPH. The protective actions of oxDHA were reversed by treatment with sodium borohydride (NaBH 4 ), which concurrently abrogated A 4 /J 4 -NP formation. Up-regulation of monocyte chemoattractant protein-1 (MCP-1) by PCB77 was markedly reduced by oxDHA, but not by un-oxidized DHA. These protective effects were proportional to the abundance of A 4 /J 4 NPs in the oxidized DHA sample. Treatment of cells with oxidized eicosapentaenoic acid (EPA, 20:5ω-3) also reduced MCP-1 expression, but less than oxDHA. Treatment with DHA-derived cyclopentenones also increased DNA binding of NF-E2-related factor-2 (Nrf2) and downstream expression of NAD(P)H:quinone oxidoreductase (NQO1), similarly to the Nrf-2 activator sulforaphane. Furthermore, sulforaphane prevented PCB77-induced MCP-1 expression, suggesting that activation of Nrf-2 mediates the observed protection against PCB77 toxicity. Our data implicate A 4 /J 4 -NPs as mediators of omega-3 fatty acid-mediated protection against the endothelial toxicity of coplanar PCBs.

Vascular endothelial genes that are responsive to tumor necrosis factor-alpha in vitro are expressed in atherosclerotic lesions, including inhibitor of apoptosis protein-1, stannin, and two novel genes

NARCIS (Netherlands)

Horrevoets, A. J.; Fontijn, R. D.; van Zonneveld, A. J.; de Vries, C. J.; ten Cate, J. W.; Pannekoek, H.

1999-01-01

Activation and dysfunction of endothelial cells play a prominent role in patho-physiological processes such as atherosclerosis. We describe the identification by differential display of 106 cytokine-responsive gene fragments from endothelial cells, activated by monocyte conditioned medium or tumor

Ex vivo expanded human regulatory T cells delay islet allograft rejection via inhibiting islet-derived monocyte chemoattractant protein-1 production in CD34+ stem cells-reconstituted NOD-scid IL2rγnull mice.

Science.gov (United States)

Xiao, Fang; Ma, Liang; Zhao, Min; Huang, Guocai; Mirenda, Vincenzo; Dorling, Anthony; Lechler, Robert; Lombardi, Giovanna

2014-01-01

Type 1 diabetes mellitus (T1DM) is an autoimmune disease caused by immune-mediated destruction of insulin-secreting β cells of the pancreas. Near complete dependence on exogenous insulin makes T1DM very difficult to control, with the result that patients are exposed to high blood glucose and risk of diabetic complications and/or intermittent low blood glucose that can cause unconsciousness, fits and even death. Allograft transplantation of pancreatic islets restores normoglycemia with a low risk of surgical complications. However, although successful immediately after transplantation, islets are progressively lost, with most of the patients requiring exogenous insulin within 2 years post-transplant. Therefore, there is an urgent requirement for the development of new strategies to prevent islet rejection. In this study, we explored the importance of human regulatory T cells in the control of islets allograft rejection. We developed a pre-clinical model of human islet transplantation by reconstituting NOD-scid IL2rγnull mice with cord blood-derived human CD34+ stem cells and demonstrated that although the engrafted human immune system mediated the rejection of human islets, their survival was significantly prolonged following adoptive transfer of ex vivo expanded human Tregs. Mechanistically, Tregs inhibited the infiltration of innate immune cells and CD4+ T cells into the graft by down-regulating the islet graft-derived monocyte chemoattractant protein-1. Our findings might contribute to the development of clinical strategies for Treg therapy to control human islet rejection. We also show for the first time that CD34+ cells-reconstituted NOD-scid IL2rγnull mouse model could be beneficial for investigating human innate immunity in vivo.

Ex Vivo Expanded Human Regulatory T Cells Delay Islet Allograft Rejection via Inhibiting Islet-Derived Monocyte Chemoattractant Protein-1 Production in CD34+ Stem Cells-Reconstituted NOD-scid IL2rγnull Mice

Science.gov (United States)

Xiao, Fang; Ma, Liang; Zhao, Min; Huang, Guocai; Mirenda, Vincenzo; Dorling, Anthony

2014-01-01

Type 1 diabetes mellitus (T1DM) is an autoimmune disease caused by immune-mediated destruction of insulin-secreting β cells of the pancreas. Near complete dependence on exogenous insulin makes T1DM very difficult to control, with the result that patients are exposed to high blood glucose and risk of diabetic complications and/or intermittent low blood glucose that can cause unconsciousness, fits and even death. Allograft transplantation of pancreatic islets restores normoglycemia with a low risk of surgical complications. However, although successful immediately after transplantation, islets are progressively lost, with most of the patients requiring exogenous insulin within 2 years post-transplant. Therefore, there is an urgent requirement for the development of new strategies to prevent islet rejection. In this study, we explored the importance of human regulatory T cells in the control of islets allograft rejection. We developed a pre-clinical model of human islet transplantation by reconstituting NOD-scid IL2rγnull mice with cord blood-derived human CD34+ stem cells and demonstrated that although the engrafted human immune system mediated the rejection of human islets, their survival was significantly prolonged following adoptive transfer of ex vivo expanded human Tregs. Mechanistically, Tregs inhibited the infiltration of innate immune cells and CD4+ T cells into the graft by down-regulating the islet graft-derived monocyte chemoattractant protein-1. Our findings might contribute to the development of clinical strategies for Treg therapy to control human islet rejection. We also show for the first time that CD34+ cells-reconstituted NOD-scid IL2rγnull mouse model could be beneficial for investigating human innate immunity in vivo. PMID:24594640

Ex vivo expanded human regulatory T cells delay islet allograft rejection via inhibiting islet-derived monocyte chemoattractant protein-1 production in CD34+ stem cells-reconstituted NOD-scid IL2rγnull mice.

Directory of Open Access Journals (Sweden)

Fang Xiao

Full Text Available Type 1 diabetes mellitus (T1DM is an autoimmune disease caused by immune-mediated destruction of insulin-secreting β cells of the pancreas. Near complete dependence on exogenous insulin makes T1DM very difficult to control, with the result that patients are exposed to high blood glucose and risk of diabetic complications and/or intermittent low blood glucose that can cause unconsciousness, fits and even death. Allograft transplantation of pancreatic islets restores normoglycemia with a low risk of surgical complications. However, although successful immediately after transplantation, islets are progressively lost, with most of the patients requiring exogenous insulin within 2 years post-transplant. Therefore, there is an urgent requirement for the development of new strategies to prevent islet rejection. In this study, we explored the importance of human regulatory T cells in the control of islets allograft rejection. We developed a pre-clinical model of human islet transplantation by reconstituting NOD-scid IL2rγnull mice with cord blood-derived human CD34+ stem cells and demonstrated that although the engrafted human immune system mediated the rejection of human islets, their survival was significantly prolonged following adoptive transfer of ex vivo expanded human Tregs. Mechanistically, Tregs inhibited the infiltration of innate immune cells and CD4+ T cells into the graft by down-regulating the islet graft-derived monocyte chemoattractant protein-1. Our findings might contribute to the development of clinical strategies for Treg therapy to control human islet rejection. We also show for the first time that CD34+ cells-reconstituted NOD-scid IL2rγnull mouse model could be beneficial for investigating human innate immunity in vivo.

Th1/M1 conversion to Th2/M2 responses in models of inflammation lacking cell death stimulates maturation of monocyte precursors to fibroblasts

Directory of Open Access Journals (Sweden)

JoAnn eTrial

2013-09-01

Full Text Available We have demonstrated that cardiac fibrosis arises from the differentiation of monocyte-derived fibroblasts. We present here evidence that this process requires sequential Th1 and Th2 induction promoting analogous M1 (classically activated and M2 (alternatively activated macrophage polarity. Our models are 1 mice subjected to daily repetitive ischemia reperfusion (I/R without infarction and 2 the in vitro transmigration of human mononuclear leukocytes through human cardiac microvascular endothelium. In the mouse heart, leukocytes entered after I/R in response to monocyte chemoattractant protein-1 (MCP-1 which is the major cytokine induced by this protocol. Monocytes within the heart then differentiated into fibroblasts making collagen while bearing the markers of M2 macrophages. T cells were seen in these hearts as well as in the human heart with cardiomyopathy. In the in vitro model, transmigration of the leukocytes was likewise induced by MCP-1 and some monocytes matured into fibroblasts bearing M2 markers. In this model, the MCP-1 stimulus induced a transient Th1 and M1 response that developed into a predominately Th2 and M2 response. An increase in the Th2 product IL-13 was present in both the human and the mouse models, consistent with its known role in fibrosis. In these simplified models, in which there is no cell death to stimulate an anti-inflammatory response, there is nonetheless a resolution of inflammation enabling a profibrotic environment. This induces the maturation of monocyte precursors into fibroblasts.

Cytokine concentration in aqueous humor of eyes with diabetic macular edema.

Science.gov (United States)

Jonas, Jost B; Jonas, Rahul A; Neumaier, Michael; Findeisen, Peter

2012-01-01

To measure cytokine concentrations in aqueous humor of eyes with diffuse diabetic macular edema. The interventional clinical comparative study included a study group of 23 patients with diffuse diabetic macular edema and a control group of 22 patients undergoing cataract surgery. Cytokine concentrations were measured in aqueous humor samples using a Luminex xMAP suspension array technology. In the study group as compared with the control group, significantly higher concentrations were measured for epidermal growth factor (P < 0.001), human growth factor (P < 0.001), intercellular adhesion molecule-1 (ICAM-1; P < 0.001), interleukin (IL)-1a2 (P = 0.04), IL-6 (P = 0.001), IL-8 (P < 0.001), interferon gamma-induced protein (P = 0.004), monocyte chemoattractant protein-1 (P < 0.001), monokine induced by interferon gamma (P < 0.001), matrix metalloproteinase 1 (P = 0.02), matrix metalloproteinase 9 (P < 0.001), plasminogen activator inhibitor 1 (P < 0.001), placenta growth factor (P < 0.001), tissue growth factor beta (P = 0.003), vascular cell adhesion molecule (P < 0.001), and vascular endothelial growth factor (P < 0.001). Retinal macula thickness was significantly associated with the concentrations of the epidermal growth factor (P = 0.005; ρ = 0.45), ICAM-1 (P < 0.001; ρ = 0.65), IL-3 (P = 0.002; ρ = 0.48), IL-6 (P = 0.003; ρ = 0.47), IL-8 (P < 0.001; ρ = 0.71), monocyte chemoattractant protein-1 (P = 0.001; ρ = 0.53), monokine induced by interferon gamma (P < 0.001; ρ = 0.57), matrix metalloproteinase 9 (P < 0.001; ρ = 0.61), tissue growth factor beta (P = 0.01; ρ = 0.42), placenta growth factor (P = 0.004; ρ = 0.46), vascular cell adhesion molecule (P = 0.006; ρ = 0.44), and vascular endothelial growth factor (P = 0.01; ρ = 0.42). In multivariate analysis, macular thickness remained to be significantly associated with the concentration of ICAM-1 (P = 0.03; r = 0.30). Vascular endothelial growth factor concentrations were correlated with concentration

Alveolar macrophage–derived type I interferons orchestrate innate immunity to RSV through recruitment of antiviral monocytes

Science.gov (United States)

Goritzka, Michelle; Makris, Spyridon; Kausar, Fahima; Durant, Lydia R.; Pereira, Catherine; Kumagai, Yutaro; Culley, Fiona J.; Mack, Matthias; Akira, Shizuo

2015-01-01

Type I interferons (IFNs) are important for host defense from viral infections, acting to restrict viral production in infected cells and to promote antiviral immune responses. However, the type I IFN system has also been associated with severe lung inflammatory disease in response to respiratory syncytial virus (RSV). Which cells produce type I IFNs upon RSV infection and how this directs immune responses to the virus, and potentially results in pathological inflammation, is unclear. Here, we show that alveolar macrophages (AMs) are the major source of type I IFNs upon RSV infection in mice. AMs detect RSV via mitochondrial antiviral signaling protein (MAVS)–coupled retinoic acid–inducible gene 1 (RIG-I)–like receptors (RLRs), and loss of MAVS greatly compromises innate immune restriction of RSV. This is largely attributable to loss of type I IFN–dependent induction of monocyte chemoattractants and subsequent reduced recruitment of inflammatory monocytes (infMo) to the lungs. Notably, the latter have potent antiviral activity and are essential to control infection and lessen disease severity. Thus, infMo recruitment constitutes an important and hitherto underappreciated, cell-extrinsic mechanism of type I IFN–mediated antiviral activity. Dysregulation of this system of host antiviral defense may underlie the development of RSV-induced severe lung inflammation. PMID:25897172

involvement of multiple cell lineages in atherogenesis

African Journals Online (AJOL)

2017-07-12

Jul 12, 2017 ... Elucidation of all ... molecular mechanisms which underly this .... intima. Monocyte chemoattractant protein-1 ... cell interaction, release of microparticles, pro – ..... Monocytes and macrophages dynamics during atherogenesis.

Monoclonal antibody to a subset of human monocytes found only in the peripheral blood and inflammatory tissues

Energy Technology Data Exchange (ETDEWEB)

Zwadlo, G.; Schlegel, R.; Sorg, C.

1986-07-15

A monoclonal antibody is described that was generated by immunizing mice with cultured human blood monocytes. The antibody (27E10) belongs to the IgG1 subclass and detects a surface antigen at M/sub r/ 17,000 that is found on 20% of peripheral blood monocytes. The antigen is increasingly expressed upon culture of monocytes, reaching a maximum between days 2 and 3. Stimulation of monocytes with interferon-..gamma.. (IFN-..gamma..), 12-O-tetradecanoyl-phorbol-13-acetate (TPA), and lipopolysaccharide (LPS) Ylalanine (fMLP) increased the 27E10 antigen density. The amount of 27E10-positive cells is not or is only weakly affected. The antigen is absent from platelets, lymphotyces, and all tested human cell lines, yet it cross-reacts with 15% of freshly isolated granulocytes. By using the indirect immunoperoxidase technique, the antibody is found to be negative on cryostat sections of normal human tissue (skin, lung, and colon) and positive on only a few monocyte-like cells in liver and on part of the cells of the splenic red pulp. In inflammatory tissue, however, the antibody is positive on monocytes/macrophages and sometimes on endothelial cells and epidermal cells, depending on the stage and type of inflammation, e.g., BCG ranulomas are negative, whereas psoriasis vulgaris, atopic dermatitis, erythrodermia, pressure urticaria, and periodontitis contain positively staining cells. In contact eczemas at different times after elicitation (6 hr, 24 hr, and 72 hr), the 27E10 antigen is seen first after 24 hr on a few infiltrating monocytes/macrophages, which increase in numbers after 72 hr.

Synthesis of sFlt-1 by platelet-monocyte aggregates contributes to the pathogenesis of preeclampsia

Science.gov (United States)

Major, Heather D.; Cambell, Robert A.; Silver, Robert M.; Branch, D. Ware; Weyrich, Andrew S.

2014-01-01

Objective Soluble fms-like tyrosine kinase (sFlt-1) is an important mediator in the pathogenesis of preeclampsia. We sought to determine if platelet-monocyte aggregates (PMAs) produced sFlt-1 and if PMAs contributed to sFlt-1 production in preeclampsia. Study Design Case-control study of sFlt-1 release from PMAs using blood samples from women with preeclampsia matched by gestational age to pregnant controls. A third group of nonpregnant, reproductive-age women comprised an additional control group. Experiments were also performed using blood from non-pregnant women to elucidate if inducing PMAs could stimulate sFlt-1 production, and if so, to determine the necessary receptors and pathways. Results Women with preeclampsia had increased total Flt-1 concentrations in platelets and monocytes at baseline compared to pregnant controls (25 vs. 10 pg/ml, p=0.0003). sFlt-1 production was elicited from monocytes incubated with thrombin-activated platelets from non-pregnant women. sFlt-1 production was regulated at the transcriptional level by p38 and NF-κB dependent pathways. Conclusion Activated platelets in preeclampsia bind monocytes to generate sFlt-1. PMAs are a previously unrecognized source of sFlt-1 that may contribute to endothelial dysfunction and systemic inflammation commonly observed in preeclampsia. PMID:24440566

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

Science.gov (United States)

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.

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

Science.gov (United States)

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.

Functional relevance of protein glycosylation to the pro-inflammatory effects of extracellular matrix metalloproteinase inducer (EMMPRIN) on monocytes/macrophages.

Science.gov (United States)

Ge, Heng; Yuan, Wei; Liu, Jidong; He, Qing; Ding, Song; Pu, Jun; He, Ben

2015-01-01

Extracellular matrix metalloproteinase inducer (EMMPRIN) is an important pro-inflammatory protein involved in the cellular functions of monocytes/macrophages. We have hypothesized that high-level heterogeneousness of protein glycosylation of EMMPRIN may have functional relevance to its biological effects and affect the inflammatory activity of monocytes/macrophages. The glycosylation patterns of EMMPRIN expressed by monocytes/macrophages (THP-1 cells) in response to different extracellular stimuli were observed, and the structures of different glycosylation forms were identified. After the purification of highly- and less-glycosylated proteins respectively, the impacts of different glycosylation forms on the pro-inflammatory effects of EMMPRIN were examined in various aspects, such as cell adhesion to endothelial cells, cell migrations, cytokine expression, and activation of inflammatory signalling pathway. 1) It was mainly the highly-glycosylated form of EMMPRIN (HG-EMMPRIN) that increased after being exposed to inflammatory signals (PMA and H2O2). 2) Glycosylation of EMMPRIN in monocytes/macrophages led to N-linked-glycans being added to the protein, with the HG form containing complex-type glycans and the less-glycosylated form (LG) the simple type. 3) Only the HG-EMMPRIN but not the LG-EMMPRIN exhibited pro-inflammatory effects and stimulated inflammatory activities of the monocytes/macrophages (i.e., activation of ERK1/2 and NF-κB pathway, enhanced monocyte-endothelium adhesion, cell migration and matrix metalloproteinase -9 expression). Post-transcriptional glycosylation represents an important mechanism that determines the biological effects of EMMPRIN in monocytes/macrophages. Glycosylation of EMMPRIN may serve as a potential target for regulating the inflammatory activities of monocytes/macrophages.

Functional relevance of protein glycosylation to the pro-inflammatory effects of extracellular matrix metalloproteinase inducer (EMMPRIN on monocytes/macrophages.

Directory of Open Access Journals (Sweden)

Heng Ge

Full Text Available Extracellular matrix metalloproteinase inducer (EMMPRIN is an important pro-inflammatory protein involved in the cellular functions of monocytes/macrophages. We have hypothesized that high-level heterogeneousness of protein glycosylation of EMMPRIN may have functional relevance to its biological effects and affect the inflammatory activity of monocytes/macrophages.The glycosylation patterns of EMMPRIN expressed by monocytes/macrophages (THP-1 cells in response to different extracellular stimuli were observed, and the structures of different glycosylation forms were identified. After the purification of highly- and less-glycosylated proteins respectively, the impacts of different glycosylation forms on the pro-inflammatory effects of EMMPRIN were examined in various aspects, such as cell adhesion to endothelial cells, cell migrations, cytokine expression, and activation of inflammatory signalling pathway.1 It was mainly the highly-glycosylated form of EMMPRIN (HG-EMMPRIN that increased after being exposed to inflammatory signals (PMA and H2O2. 2 Glycosylation of EMMPRIN in monocytes/macrophages led to N-linked-glycans being added to the protein, with the HG form containing complex-type glycans and the less-glycosylated form (LG the simple type. 3 Only the HG-EMMPRIN but not the LG-EMMPRIN exhibited pro-inflammatory effects and stimulated inflammatory activities of the monocytes/macrophages (i.e., activation of ERK1/2 and NF-κB pathway, enhanced monocyte-endothelium adhesion, cell migration and matrix metalloproteinase -9 expression.Post-transcriptional glycosylation represents an important mechanism that determines the biological effects of EMMPRIN in monocytes/macrophages. Glycosylation of EMMPRIN may serve as a potential target for regulating the inflammatory activities of monocytes/macrophages.

Progranulin protects vascular endothelium against atherosclerotic inflammatory reaction via Akt/eNOS and nuclear factor-κB pathways.

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Hwang, Hwan-Jin; Jung, Tae Woo; Hong, Ho Cheol; Choi, Hae Yoon; Seo, Ji-A; Kim, Sin Gon; Kim, Nan Hee; Choi, Kyung Mook; Choi, Dong Seop; Baik, Sei Hyun; Yoo, Hye Jin

2013-01-01

Atherosclerosis is considered a chronic inflammatory disease, initiated by activation and dysfunction of the endothelium. Recently, progranulin has been regarded as an important modulator of inflammatory processes; however, the role for prgranulin in regulating inflammation in vascular endothelial cells has not been described. Signaling pathways mediated by progranulin were analyzed in human umbilical vein endothelial cells (HUVECs) treated with progranulin. Progranulin significantly induced Akt and endothelial nitric oxide synthase (eNOS) phosphorylation in HUVECs, an effect that was blocked with Akt inhibitor. Furthermore, nitric oxide (NO) level, the end product of Akt/eNOS pathway, was significantly upregulated after progranulin treatment. Next, we showed that progranulin efficiently inhibited lipopolysaccharide (LPS)-mediated pro-inflammatory signaling. LPS-induced phosphorylation of IκB and nuclear factor-κB (NF-κB) levels decreased after progranulin treatment. Also, progranulin blocked translocation of NF-κB from the cytosol to the nucleus. In addition, progranulin significantly reduced the expression of vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) by inhibiting binding of NF- κB to their promoter regions and blocked attachment of monocytes to HUVECs. Progranulin also significantly reduced the expression of tumor necrosis factor receptor-α (TNF-α) and monocyte chemo-attractant protein-1 (MCP-1), the crucial inflammatory molecules known to aggravate atherosclerosis. Progranulin efficiently inhibited LPS-mediated pro-inflammatory signaling in endothelial cells through activation of the Akt/eNOS pathway and attenuation of the NF-κB pathway, suggesting its protective roles in vascular endothelium against inflammatory reaction underlying atherosclerosis.

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.

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.

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

[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.

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

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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

IL-17A influences essential functions of the monocyte/macrophage lineage and is involved in advanced murine and human atherosclerosis.

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Erbel, Christian; Akhavanpoor, Mohammadreza; Okuyucu, Deniz; Wangler, Susanne; Dietz, Alex; Zhao, Li; Stellos, Konstantinos; Little, Kristina M; Lasitschka, Felix; Doesch, Andreas; Hakimi, Maani; Dengler, Thomas J; Giese, Thomas; Blessing, Erwin; Katus, Hugo A; Gleissner, Christian A

2014-11-01

Atherosclerosis is a chronic inflammatory disease. Lesion progression is primarily mediated by cells of the monocyte/macrophage lineage. IL-17A is a proinflammatory cytokine, which modulates immune cell trafficking and is involved inflammation in (auto)immune and infectious diseases. But the role of IL-17A still remains controversial. In the current study, we investigated effects of IL-17A on advanced murine and human atherosclerosis, the common disease phenotype in clinical care. The 26-wk-old apolipoprotein E-deficient mice were fed a standard chow diet and treated either with IL-17A mAb (n = 15) or irrelevant Ig (n = 10) for 16 wk. Furthermore, essential mechanisms of IL-17A in atherogenesis were studied in vitro. Inhibition of IL-17A markedly prevented atherosclerotic lesion progression (p = 0.001) by reducing inflammatory burden and cellular infiltration (p = 0.01) and improved lesion stability (p = 0.01). In vitro experiments showed that IL-17A plays a role in chemoattractance, monocyte adhesion, and sensitization of APCs toward pathogen-derived TLR4 ligands. Also, IL-17A induced a unique transcriptome pattern in monocyte-derived macrophages distinct from known macrophage types. Stimulation of human carotid plaque tissue ex vivo with IL-17A induced a proinflammatory milieu and upregulation of molecules expressed by the IL-17A-induced macrophage subtype. In this study, we show that functional blockade of IL-17A prevents atherosclerotic lesion progression and induces plaque stabilization in advanced lesions in apolipoprotein E-deficient mice. The underlying mechanisms involve reduced inflammation and distinct effects of IL-17A on monocyte/macrophage lineage. In addition, translational experiments underline the relevance for the human system. Copyright © 2014 by The American Association of Immunologists, Inc.

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

The CD157-integrin partnership controls transendothelial migration and adhesion of human monocytes.

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Lo Buono, Nicola; Parrotta, Rossella; Morone, Simona; Bovino, Paola; Nacci, Giulia; Ortolan, Erika; Horenstein, Alberto L; Inzhutova, Alona; Ferrero, Enza; Funaro, Ada

2011-05-27

CD157, a member of the CD38 gene family, is an NAD-metabolizing ectoenzyme and a signaling molecule whose role in polarization, migration, and diapedesis of human granulocytes has been documented; however, the molecular events underpinning this role remain to be elucidated. This study focused on the role exerted by CD157 in monocyte migration across the endothelial lining and adhesion to extracellular matrix proteins. The results demonstrated that anti-CD157 antibodies block monocyte transmigration and adhesion to fibronectin and fibrinogen but that CD157 cross-linking is sufficient to overcome the block, suggesting an active signaling role for the molecule. Consistent with this is the observation that CD157 is prevalently located within the detergent-resistant membrane microdomains to which, upon clustering, it promotes the recruitment of β(1) and β(2) integrin, which, in turn, leads to the formation of a multimolecular complex favoring signal transduction. This functional cross-talk with integrins allows CD157 to act as a receptor despite its intrinsic structural inability to do so on its own. Intracellular signals mediated by CD157 rely on the integrin/Src/FAK (focal adhesion kinase) pathway, resulting in increased activity of the MAPK/ERK1/2 and the PI3K/Akt downstream signaling pathways, which are crucial in the control of monocyte transendothelial migration. Collectively, these findings indicate that CD157 acts as a molecular organizer of signaling-competent membrane microdomains and that it forms part of a larger molecular machine ruled by integrins. The CD157-integrin partnership provides optimal adhesion and transmigration of human monocytes.

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.

Action of a diffusible target-derived chemoattractant on cortical axon branch induction and directed growth.

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Sato, M; Lopez-Mascaraque, L; Heffner, C D; O'Leary, D D

1994-10-01

Cortical axons innervate their brainstem target, the basilar pons, by the initiation and extension of collateral branches interstitially along their length. To address whether a diffusible pons-derived chemoattractant controls these events, we used cocultures in collagen matrices and time-lapse microscopy. Pontine explants enhanced by 5-fold the de novo initiation of transient branches along cortical axons; most branches were directed toward pons. Of the branches extended toward pons, 2%-3% were stabilized; those extended away were not. Pontine explants also enhanced the stable bifurcation of growth cones and prompted directional changes by growth cone turning and collateral extension. These effects were distance dependent and mimicked by pons-conditioned medium. This evidence indicates that the pons activity promotes branch initiation interstitially along cortical axons, a novel property for a chemoattractant, and provides a directional cue for their growth. These findings suggest that the pons chemoattractant serves as a diffusible target-recognition molecule.

Primary Phenomenon in the Network Formation of Endothelial Cells: Effect of Charge.

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Arai, Shunto

2015-12-07

Blood vessels are essential organs that are involved in the supply of nutrients and oxygen and play an important role in regulating the body's internal environment, including pH, body temperature, and water homeostasis. Many studies have examined the formation of networks of endothelial cells. The results of these studies have revealed that vascular endothelial growth factor (VEGF) affects the interactions of these cells and modulates the network structure. Though almost all previous simulation studies have assumed that the chemoattractant VEGF is present before network formation, vascular endothelial cells secrete VEGF only after the cells bind to the substrate. This suggests VEGF is not essential for vasculogenesis especially at the early stage. Using a simple experiment, we find chain-like structures which last quite longer than it is expected, unless the energetically stable cluster should be compact. Using a purely physical model and simulation, we find that the hydrodynamic interaction retard the compaction of clusters and that the chains are stabilized through the effects of charge. The charge at the surface of the cells affect the interparticle potential, and the resulting repulsive forces prevent the chains from folding. The ions surrounding the cells may also be involved in this process.

In vitro and in vivo dependency of chemokine generation on C5a and TNF-alpha

DEFF Research Database (Denmark)

Czermak, B J; Sarma, V; Bless, N M

1999-01-01

production in vitro and in vivo. Two rat CXC chemokines (macrophage inflammatory protein (MIP)-2 and cytokine-induced neutrophil chemoattractant (CINC)) as well as three rat CC chemokines (MIP-1alpha, MIP-1beta, and monocyte chemoattractant protein (MCP)-1) were investigated. Chemokine generation in vitro...

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

(−-Epigallocatechin gallate inhibits endotoxin-induced expression of inflammatory cytokines in human cerebral microvascular endothelial cells

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Li Jieliang

2012-07-01

Full Text Available Abstract Background (−-Epigallocatechin gallate (EGCG is a major polyphenol component of green tea that has antioxidant activities. Lipopolysaccharide (LPS induces inflammatory cytokine production and impairs blood–brain barrier (BBB integrity. We examined the effect of EGCG on LPS-induced expression of the inflammatory cytokines in human cerebral microvascular endothelial cells (hCMECs and BBB permeability. Methods The expression of TNF-α, IL-1β and monocyte chemotactic protein-1 (MCP-1/CCL2 was determined by quantitative real time PCR (qRT-PCR and ELISA. Intercellular adhesion molecule 1 (ICAM-1 and vascular cell adhesion molecule (VCAM in hCMECs were examined by qRT-PCR and Western blotting. Monocytes that adhered to LPS-stimulated endothelial cells were measured by monocyte adhesion assay. Tight junctional factors were detected by qRT-PCR (Claudin 5 and Occludin and immunofluorescence staining (Claudin 5 and ZO-1. The permeability of the hCMEC monolayer was determined by fluorescence spectrophotometry of transmembrane fluorescin and transendothelial electrical resistance (TEER. NF-kB activation was measured by luciferase assay. Results EGCG significantly suppressed the LPS-induced expression of IL-1β and TNF-α in hCMECs. EGCG also inhibited the expression of MCP-1/CCL2, VCAM-1 and ICAM-1. Functional analysis showed that EGCG induced the expression of tight junction proteins (Occludin and Claudin-5 in hCMECs. Investigation of the mechanism showed that EGCG had the ability to inhibit LPS-mediated NF-κB activation. In addition, 67-kD laminin receptor was involved in the anti-inflammatory effect of EGCG. Conclusions Our results demonstrated that LPS induced inflammatory cytokine production in hCMECs, which could be attenuated by EGCG. These data indicate that EGCG has a therapeutic potential for endotoxin-mediated endothelial inflammation.

Sphingosine 1-phosphate receptor 5 mediates the immune quiescence of the human brain endothelial barrier

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van Doorn Ruben

2012-06-01

Full Text Available Abstract Background The sphingosine 1-phosphate (S1P receptor modulator FTY720P (Gilenya® potently reduces relapse rate and lesion activity in the neuroinflammatory disorder multiple sclerosis. Although most of its efficacy has been shown to be related to immunosuppression through the induction of lymphopenia, it has been suggested that a number of its beneficial effects are related to altered endothelial and blood–brain barrier (BBB functionality. However, to date it remains unknown whether brain endothelial S1P receptors are involved in the maintenance of the function of the BBB thereby mediating immune quiescence of the brain. Here we demonstrate that the brain endothelial receptor S1P5 largely contributes to the maintenance of brain endothelial barrier function. Methods We analyzed the expression of S1P5 in human post-mortem tissues using immunohistochemistry. The function of S1P5 at the BBB was assessed in cultured human brain endothelial cells (ECs using agonists and lentivirus-mediated knockdown of S1P5. Subsequent analyses of different aspects of the brain EC barrier included the formation of a tight barrier, the expression of BBB proteins and markers of inflammation and monocyte transmigration. Results We show that activation of S1P5 on cultured human brain ECs by a selective agonist elicits enhanced barrier integrity and reduced transendothelial migration of monocytes in vitro. These results were corroborated by genetically silencing S1P5 in brain ECs. Interestingly, functional studies with these cells revealed that S1P5 strongly contributes to brain EC barrier function and underlies the expression of specific BBB endothelial characteristics such as tight junctions and permeability. In addition, S1P5 maintains the immunoquiescent state of brain ECs with low expression levels of leukocyte adhesion molecules and inflammatory chemokines and cytokines through lowering the activation of the transcription factor NFκB. Conclusion Our

Progranulin protects vascular endothelium against atherosclerotic inflammatory reaction via Akt/eNOS and nuclear factor-κB pathways.

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Hwan-Jin Hwang

Full Text Available OBJECTIVE: Atherosclerosis is considered a chronic inflammatory disease, initiated by activation and dysfunction of the endothelium. Recently, progranulin has been regarded as an important modulator of inflammatory processes; however, the role for prgranulin in regulating inflammation in vascular endothelial cells has not been described. METHOD AND RESULTS: Signaling pathways mediated by progranulin were analyzed in human umbilical vein endothelial cells (HUVECs treated with progranulin. Progranulin significantly induced Akt and endothelial nitric oxide synthase (eNOS phosphorylation in HUVECs, an effect that was blocked with Akt inhibitor. Furthermore, nitric oxide (NO level, the end product of Akt/eNOS pathway, was significantly upregulated after progranulin treatment. Next, we showed that progranulin efficiently inhibited lipopolysaccharide (LPS-mediated pro-inflammatory signaling. LPS-induced phosphorylation of IκB and nuclear factor-κB (NF-κB levels decreased after progranulin treatment. Also, progranulin blocked translocation of NF-κB from the cytosol to the nucleus. In addition, progranulin significantly reduced the expression of vascular cell adhesion molecule-1 (VCAM-1 and intercellular adhesion molecule-1 (ICAM-1 by inhibiting binding of NF- κB to their promoter regions and blocked attachment of monocytes to HUVECs. Progranulin also significantly reduced the expression of tumor necrosis factor receptor-α (TNF-α and monocyte chemo-attractant protein-1 (MCP-1, the crucial inflammatory molecules known to aggravate atherosclerosis. CONCLUSION: Progranulin efficiently inhibited LPS-mediated pro-inflammatory signaling in endothelial cells through activation of the Akt/eNOS pathway and attenuation of the NF-κB pathway, suggesting its protective roles in vascular endothelium against inflammatory reaction underlying atherosclerosis.

Anti-Inflammatory Effects of Pomegranate Peel Extract in THP-1 Cells Exposed to Particulate Matter PM10

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Soojin Park

2016-01-01

Full Text Available Epidemiological and experimental evidence support health risks associated with the exposure to airborne particulate matter with a diameter of <10 μM (PM10. PM10 stimulates the production of reactive oxygen species (ROS and inflammatory mediators. Thus, we assumed that natural antioxidants might provide health benefits attenuating hazardous effects of PM10. In the present study, we examined the effects of pomegranate peel extract (PPE on THP-1 monocytic cells exposed to PM10. PM10 induced cytotoxicity and the production of ROS. It also increased the expression and secretion of inflammatory cytokines, such as tumor necrosis factor-α (TNF-α, interleukin-1β (IL-1β, and monocyte chemoattractant protein-1 (MCP-1, and cell adhesion molecules, such as intercellular adhesion molecule-1 (ICAM-1 and vascular cell adhesion molecule-1 (VCAM-1. PPE at 10–100 μg mL−1 attenuated the production of ROS and the expression of TNF-α, IL-1β, MCP-1, and ICAM-1, but not VCAM-1, in THP-1 cells stimulated by PM10 (100 μg mL−1. PPE also attenuated the adhesion of PM10-stimulated THP-1 cells to EA.hy926 endothelial cells. PPE constituents, punicalagin and ellagic acid, attenuated PM10-induced monocyte adhesion to endothelial cells, and punicalagin was less cytotoxic compared to ellagic acid. The present study suggests that PPE and punicalagin may be useful in alleviating inflammatory reactions due to particulate matter.

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.

Multiple Degradation Pathways of Chemoattractant Mediated Cyclic GMP Accumulation in Dictyostelium

NARCIS (Netherlands)

Haastert, Peter J.M. van; Lookeren Campagne, Michiel M. van; Kesbeke, Fanja

1983-01-01

Chemoattractants induce a transient accumulation of cGMP levels in Dictyostelium. Intracellular cGMP levels reach a peak at 10 s and prestimulated cGMP levels are recovered at about 30 s. Intracellular and extracellular cGMP levels were detected simultaneously after stimulation of D. lacteum cells

Augmented TLR2 expression on monocytes in both human Kawasaki disease and a mouse model of coronary arteritis.

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I-Chun Lin

Full Text Available BACKGROUND: Kawasaki disease (KD of unknown immunopathogenesis is an acute febrile systemic vasculitis and the leading cause of acquired heart diseases in childhood. To search for a better strategy for the prevention and treatment of KD, this study compared and validated human KD immunopathogenesis in a mouse model of Lactobacillus casei cell wall extract (LCWE-induced coronary arteritis. METHODS: Recruited subjects fulfilled the criteria of KD and were admitted for intravenous gamma globulin (IVIG treatment at the Kaohsiung Chang Gung Memorial Hospital from 2001 to 2009. Blood samples from KD patients were collected before and after IVIG treatment, and cardiovascular abnormalities were examined by transthoracic echocardiography. Wild-type male BALB/c mice (4-week-old were intraperitoneally injected with LCWE (1 mg/mL to induce coronary arteritis. The induced immune response in mice was examined on days 1, 3, 7, and 14 post injections, and histopathology studies were performed on days 7 and 14. RESULTS: Both human KD patients and LCWE-treated mice developed coronary arteritis, myocarditis, valvulitis, and pericarditis, as well as elevated plasma levels of interleukin (IL-2, IL-6, IL-10, monocyte chemoattractant protein (MCP-1, and tumor necrosis factor (TNF-α in acute phase. Most of these proinflammatory cytokines declined to normal levels in mice, whereas normal levels were achieved in patients only after IVIG treatment, with a few exceptions. Toll-like receptor (TLR-2, but not TLR4 surface enhancement on circulating CD14+ monocytes, was augmented in KD patients before IVIG treatment and in LCWE-treated mice, which declined in patients after IVIG treatment. CONCLUSION: This result suggests that that not only TLR2 augmentation on CD14+ monocytes might be an inflammatory marker for both human KD patients and LCWE-induced CAL mouse model but also this model is feasible for studying therapeutic strategies of coronary arteritis in human KD by

Augmented TLR2 expression on monocytes in both human Kawasaki disease and a mouse model of coronary arteritis.

Science.gov (United States)

Lin, I-Chun; Kuo, Ho-Chang; Lin, Ying-Jui; Wang, Feng-Shen; Wang, Lin; Huang, Shun-Chen; Chien, Shao-Ju; Huang, Chien-Fu; Wang, Chih-Lu; Yu, Hong-Ren; Chen, Rong-Fu; Yang, Kuender D

2012-01-01

Kawasaki disease (KD) of unknown immunopathogenesis is an acute febrile systemic vasculitis and the leading cause of acquired heart diseases in childhood. To search for a better strategy for the prevention and treatment of KD, this study compared and validated human KD immunopathogenesis in a mouse model of Lactobacillus casei cell wall extract (LCWE)-induced coronary arteritis. Recruited subjects fulfilled the criteria of KD and were admitted for intravenous gamma globulin (IVIG) treatment at the Kaohsiung Chang Gung Memorial Hospital from 2001 to 2009. Blood samples from KD patients were collected before and after IVIG treatment, and cardiovascular abnormalities were examined by transthoracic echocardiography. Wild-type male BALB/c mice (4-week-old) were intraperitoneally injected with LCWE (1 mg/mL) to induce coronary arteritis. The induced immune response in mice was examined on days 1, 3, 7, and 14 post injections, and histopathology studies were performed on days 7 and 14. Both human KD patients and LCWE-treated mice developed coronary arteritis, myocarditis, valvulitis, and pericarditis, as well as elevated plasma levels of interleukin (IL)-2, IL-6, IL-10, monocyte chemoattractant protein (MCP)-1, and tumor necrosis factor (TNF)-α in acute phase. Most of these proinflammatory cytokines declined to normal levels in mice, whereas normal levels were achieved in patients only after IVIG treatment, with a few exceptions. Toll-like receptor (TLR)-2, but not TLR4 surface enhancement on circulating CD14+ monocytes, was augmented in KD patients before IVIG treatment and in LCWE-treated mice, which declined in patients after IVIG treatment. This result suggests that that not only TLR2 augmentation on CD14+ monocytes might be an inflammatory marker for both human KD patients and LCWE-induced CAL mouse model but also this model is feasible for studying therapeutic strategies of coronary arteritis in human KD by modulating TLR2-mediated immune activation on CD14

The CD157-Integrin Partnership Controls Transendothelial Migration and Adhesion of Human Monocytes*

Science.gov (United States)

Lo Buono, Nicola; Parrotta, Rossella; Morone, Simona; Bovino, Paola; Nacci, Giulia; Ortolan, Erika; Horenstein, Alberto L.; Inzhutova, Alona; Ferrero, Enza; Funaro, Ada

2011-01-01

CD157, a member of the CD38 gene family, is an NAD-metabolizing ectoenzyme and a signaling molecule whose role in polarization, migration, and diapedesis of human granulocytes has been documented; however, the molecular events underpinning this role remain to be elucidated. This study focused on the role exerted by CD157 in monocyte migration across the endothelial lining and adhesion to extracellular matrix proteins. The results demonstrated that anti-CD157 antibodies block monocyte transmigration and adhesion to fibronectin and fibrinogen but that CD157 cross-linking is sufficient to overcome the block, suggesting an active signaling role for the molecule. Consistent with this is the observation that CD157 is prevalently located within the detergent-resistant membrane microdomains to which, upon clustering, it promotes the recruitment of β1 and β2 integrin, which, in turn, leads to the formation of a multimolecular complex favoring signal transduction. This functional cross-talk with integrins allows CD157 to act as a receptor despite its intrinsic structural inability to do so on its own. Intracellular signals mediated by CD157 rely on the integrin/Src/FAK (focal adhesion kinase) pathway, resulting in increased activity of the MAPK/ERK1/2 and the PI3K/Akt downstream signaling pathways, which are crucial in the control of monocyte transendothelial migration. Collectively, these findings indicate that CD157 acts as a molecular organizer of signaling-competent membrane microdomains and that it forms part of a larger molecular machine ruled by integrins. The CD157-integrin partnership provides optimal adhesion and transmigration of human monocytes. PMID:21478153

Polystyrene-Divinylbenzene-Based Adsorbents Reduce Endothelial Activation and Monocyte Adhesion Under Septic Conditions in a Pore Size-Dependent Manner

OpenAIRE

Eichhorn, Tanja; Rauscher, Sabine; Hammer, Caroline; Gr?ger, Marion; Fischer, Michael B.; Weber, Viktoria

2016-01-01

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-diviny...

Invasion of human aortic endothelial cells by oral viridans group streptococci and induction of inflammatory cytokine production.

Science.gov (United States)

Nagata, E; de Toledo, A; Oho, T

2011-02-01

Oral viridans group streptococci are the major commensal bacteria of the supragingival oral biofilm and have been detected in human atheromatous plaque. Atherosclerosis involves an ongoing inflammatory response, reportedly involving chronic infection caused by multiple pathogens. The aim of this study was to examine the invasion of human aortic endothelial cells (HAECs) by oral viridans group streptococci and the subsequent cytokine production by viable invaded HAECs. The invasion of HAECs by bacteria was examined using antibiotic protection assays and was visualized by confocal scanning laser microscopy. The inhibitory effects of catalase and cytochalasin D on the invasion of HAECs were also examined. The production of cytokines by invaded or infected HAECs was determined using enzyme-linked immunosorbent assays, and a real-time polymerase chain reaction method was used to evaluate the expression of cytokine messenger RNA. The oral streptococci tested were capable of invading HAECs. The number of invasive bacteria increased with the length of the co-culture period. After a certain co-culture period, some organisms were cytotoxic to the HAECs. Catalase and cytochalasin D inhibited the invasion of HAECs by the organism. HAECs invaded by Streptococcus mutans Xc, Streptococcus gordonii DL1 (Challis), Streptococcus gordonii ATCC 10558 and Streptococcus salivarius ATCC 13419 produced more cytokine(s) (interleukin-6, interleukin-8, monocyte chemoattractant protein-1) than non-invaded HAECs. The HAECs invaded by S. mutans Xc produced the largest amounts of cytokines, and the messenger RNA expression of cytokines by invaded HAECs increased markedly compared with that by non-invaded HAECs. These results suggest that oral streptococci may participate in the pathogenesis of atherosclerosis. © 2010 John Wiley & Sons A/S.

Circulating microparticles in acute diabetic Charcot foot exhibit a high content of inflammatory cytokines, and support monocyte-to-osteoclast cell induction.

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Pasquier, Jennifer; Thomas, Binitha; Hoarau-Véchot, Jessica; Odeh, Tala; Robay, Amal; Chidiac, Omar; Dargham, Soha R; Turjoman, Rebal; Halama, Anna; Fakhro, Khalid; Menzies, Robert; Jayyousi, Amin; Zirie, Mahmoud; Al Suwaidi, Jassim; Rafii, Arash; Malik, Rayaz A; Talal, Talal; Abi Khalil, Charbel

2017-11-27

Circulating microparticles (MPs) are major mediators in cardiovascular complications of type 2 diabetes (T2D); however, their contribution to Charcot foot (CF) disease is not known. Here, we purified and assessed the origin, concentration and content of circulating MPs from 33 individuals: 11 with T2D and acute CF, 11 T2D patients with equivalent neuropathy and 11 non-diabetic controls. First, we demonstrated that there were no differences in the distribution of MPs of endothelial, platelet origin among the 3 groups. However, MPs from leukocytes and monocytes origin were increased in CF patients. Moreover, we demonstrated that monocytes-derived MPs originated more frequently from intermediate and non-classical monocytes in CF patients. Five cytokines (G-CSF, GM-CSF, IL-1-ra, IL-2 and IL-16) were significantly increased in MPs from acute CF patients. Applying ingenuity pathways analysis, we found that those cytokines interacted well and induced the activation of pathways that are involved in osteoclast formation. Further, we treated THP-1 monocytes and monocytes sorted from healthy patients with CF-derived MPs during their differentiation into osteoclasts, which increased their differentiation into multinucleated osteoclast-like cells. Altogether, our study suggests that circulating MPs in CF disease have a high content of inflammatory cytokines and could increase osteoclast differentiation in vitro.

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

Science.gov (United States)

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.

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...

Total hip and knee replacement surgery results in changes in leukocyte and endothelial markers

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Maclean Kirsty M

2010-01-01

Full Text Available Abstract Background It is estimated that over 8 million people in the United Kingdom suffer from osteoarthritis. These patients may require orthopaedic surgical intervention to help alleviate their clinical condition. Investigations presented here was to test the hypothesis that total hip replacement (THR and total knee replacement (TKR orthopaedic surgery result in changes to leukocyte and endothelial markers thus increasing inflammatory reactions postoperatively. Methods During this 'pilot study', ten test subjects were all scheduled for THR or TKR elective surgery due to osteoarthritis. Leukocyte concentrations were measured using an automated full blood count analyser. Leukocyte CD11b (Mac-1 and CD62L cell surface expression, intracellular production of H2O2 and elastase were measured as markers of leukocyte function. Von Willebrand factor (vWF and soluble intercellular adhesion molecule-1 (sICAM-1 were measured as markers of endothelial activation. Results The results obtained during this study demonstrate that THR and TKR orthopaedic surgery result in similar changes of leukocyte and endothelial markers, suggestive of increased inflammatory reactions postoperatively. Specifically, THR and TKR surgery resulted in a leukocytosis, this being demonstrated by an increase in the total leukocyte concentration following surgery. Evidence of leukocyte activation was demonstrated by a decrease in CD62L expression and an increase in CD11b expression by neutrophils and monocytes respectively. An increase in the intracellular H2O2 production by neutrophils and monocytes and in the leukocyte elastase concentrations was also evident of leukocyte activation following orthopaedic surgery. With respect to endothelial activation, increases in vWF and sICAM-1 concentrations were demonstrated following surgery. Conclusion In general it appeared that most of the leukocyte and endothelial markers measured during these studies peaked between days 1

Celastrol nanoparticles inhibit corneal neovascularization induced by suturing in rats

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Li ZR

2012-03-01

Full Text Available Zhanrong Li1, Lin Yao1, Jingguo Li2, Wenxin Zhang1, Xianghua Wu1, Yi Liu1, Miaoli Lin1, Wenru Su1, Yongping Li1, Dan Liang11State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, 2School of Chemistry and Chemical Engineering, Sun Yat-Sen University, Guangzhou, People's Republic of ChinaPurpose: Celastrol, a traditional Chinese medicine, is widely used in anti-inflammation and anti-angiogenesis research. However, the poor water solubility of celastrol restricts its further application. This paper aims to study the effect of celastrol nanoparticles (CNPs on corneal neovascularization (CNV and determine the possible mechanism.Methods: To improve the hydrophilicity of celastrol, celastrol-loaded poly(ethylene glycol-block-poly(ε-caprolactone nanopolymeric micelles were developed. The characterization of CNPs was measured by dynamic light scattering and transmission electron microscopy analysis. Celastrol loading content and release were assessed by ultraviolet-visible analysis and high performance liquid chromatography, respectively. In vitro, human umbilical vein endothelial cell proliferation and capillary-like tube formation were assayed. In vivo, suture-induced CNV was chosen to evaluate the effect of CNPs on CNV in rats. Immunohistochemistry for CD68 assessed the macrophage infiltration of the cornea on day 6 after surgery. Real-time quantitative reverse transcription-polymerase chain reaction and enzyme-linked immunosorbent assay were used to evaluate the messenger ribonucleic acid and protein levels, respectively, of vascular endothelial growth factor, matrix metalloproteinase 9, and monocyte chemoattractant protein 1 in the cornea.Results: The mean diameter of CNPs with spherical shape was 48 nm. The celastrol loading content was 7.36%. The release behavior of CNPs in buffered solution (pH 7.4 showed a typical two-phase release profile. CNPs inhibited the proliferation of human umbilical vein endothelial

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....

Brain endothelial dysfunction in cerebral adrenoleukodystrophy.

Science.gov (United States)

Musolino, Patricia L; Gong, Yi; Snyder, Juliet M T; Jimenez, Sandra; Lok, Josephine; Lo, Eng H; Moser, Ann B; Grabowski, Eric F; Frosch, Matthew P; Eichler, Florian S

2015-11-01

See Aubourg (doi:10.1093/awv271) for a scientific commentary on this article.X-linked adrenoleukodystrophy is caused by mutations in the ABCD1 gene leading to accumulation of very long chain fatty acids. Its most severe neurological manifestation is cerebral adrenoleukodystrophy. Here we demonstrate that progressive inflammatory demyelination in cerebral adrenoleukodystrophy coincides with blood-brain barrier dysfunction, increased MMP9 expression, and changes in endothelial tight junction proteins as well as adhesion molecules. ABCD1, but not its closest homologue ABCD2, is highly expressed in human brain microvascular endothelial cells, far exceeding its expression in the systemic vasculature. Silencing of ABCD1 in human brain microvascular endothelial cells causes accumulation of very long chain fatty acids, but much later than the immediate upregulation of adhesion molecules and decrease in tight junction proteins. This results in greater adhesion and transmigration of monocytes across the endothelium. PCR-array screening of human brain microvascular endothelial cells after ABCD1 silencing revealed downregulation of both mRNA and protein levels of the transcription factor c-MYC (encoded by MYC). Interestingly, MYC silencing mimicked the effects of ABCD1 silencing on CLDN5 and ICAM1 without decreasing the levels of ABCD1 protein itself. Together, these data demonstrate that ABCD1 deficiency induces significant alterations in brain endothelium via c-MYC and may thereby contribute to the increased trafficking of leucocytes across the blood-brain barrier as seen in cerebral adrenouleukodystrophy. © The Author (2015). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Progesterone from the cumulus cells is the sperm chemoattractant secreted by the rabbit oocyte cumulus complex.

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Héctor Alejandro Guidobaldi

Full Text Available Sperm chemotaxis in mammals have been identified towards several female sources as follicular fluid (FF, oviduct fluid, and conditioned medium from the cumulus oophorus (CU and the oocyte (O. Though several substances were confirmed as sperm chemoattractant, Progesterone (P seems to be the best chemoattractant candidate, because: 1 spermatozoa express a cell surface P receptor, 2 capacitated spermatozoa are chemotactically attracted in vitro by gradients of low quantities of P; 3 the CU cells produce and secrete P after ovulation; 4 a gradient of P may be kept stable along the CU; and 5 the most probable site for sperm chemotaxis in vivo could be near and/or inside the CU. The aim of this study was to verify whether P is the sperm chemoattractant secreted by the rabbit oocyte-cumulus complex (OCC in the rabbit, as a mammalian animal model. By means of videomicroscopy and computer image analysis we observed that only the CU are a stable source of sperm attractants. The CU produce and secrete P since the hormone was localized inside these cells by immunocytochemistry and in the conditioned medium by enzyme immunoassay. In addition, rabbit spermatozoa express a cell surface P receptor detected by western blot and localized over the acrosomal region by immunocytochemistry. To confirm that P is the sperm chemoattractant secreted by the CU, the sperm chemotactic response towards the OCC conditioned medium was inhibited by three different approaches: P from the OCC conditioned medium was removed with an anti-P antibody, the attractant gradient of the OCC conditioned medium was disrupted by a P counter gradient, and the sperm P receptor was blocked with a specific antibody. We concluded that only the CU but not the oocyte secretes P, and the latter chemoattract spermatozoa by means of a cell surface receptor. Our findings may be of interest in assisted reproduction procedures in humans, animals of economic importance and endangered species.

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

Captopril increases the intensity of monocyte infection by Trypanosoma cruzi and induces human T helper type 17 cells.

Science.gov (United States)

Coelho dos Santos, J S; Menezes, C A S; Villani, F N A; Magalhães, L M D; Scharfstein, J; Gollob, K J; Dutra, W O

2010-12-01

The anti-hypertensive drug captopril is used commonly to reduce blood pressure of patients with severe forms of Chagas disease, a cardiomyopathy caused by chronic infection with the intracellular protozoan Trypanosoma cruzi. Captopril acts by inhibiting angiotensin-converting enzyme (ACE), the vasopressor metallopeptidase that generates angiotensin II and promotes the degradation of bradykinin (BK). Recent studies in mice models of Chagas disease indicated that captopril can potentiate the T helper type 1 (Th1)-directing natural adjuvant property of BK. Equipped with kinin-releasing cysteine proteases, T. cruzi trypomastigotes were shown previously to invade non-professional phagocytic cells, such as human endothelial cells and murine cardiomyocytes, through the signalling of G protein-coupled bradykinin receptors (B(2) KR). Monocytes are also parasitized by T. cruzi and these cells are known to be important for the host immune response during infection. Here we showed that captopril increases the intensity of T. cruzi infection of human monocytes in vitro. The increased parasitism was accompanied by up-regulated expression of ACE in human monocytes. While T. cruzi infection increased the expression of interleukin (IL)-10 by monocytes significantly, compared to uninfected cells, T. cruzi infection in association with captopril down-modulated IL-10 expression by the monocytes. Surprisingly, studies with peripheral blood mononuclear cells revealed that addition of the ACE inhibitor in association with T. cruzi increased expression of IL-17 by CD4(+) T cells in a B(2) KR-dependent manner. Collectively, our results suggest that captopril might interfere with host-parasite equilibrium by enhancing infection of monocytes, decreasing the expression of the modulatory cytokine IL-10, while guiding development of the proinflammatory Th17 subset. © 2010 The Authors. Clinical and Experimental Immunology © 2010 British Society for Immunology.

Orf virus interleukin-10 and vascular endothelial growth factor-E modulate gene expression in cultured equine dermal fibroblasts.

Science.gov (United States)

Wise, Lyn M; Bodaan, Christa J; Mercer, Andrew A; Riley, Christopher B; Theoret, Christine L

2016-10-01

Wounds in horses often exhibit sustained inflammation and inefficient vascularization, leading to excessive fibrosis and clinical complications such as "proud flesh". Orf virus-derived proteins, vascular endothelial growth factor (VEGF)-E and interleukin (ovIL)-10, enhance angiogenesis and control inflammation and fibrosis in skin wounds of laboratory animals. The study aimed to determine if equine dermal cells respond to VEGF-E and ovIL-10. Equine dermal cells are expected to express VEGF and IL-10 receptors, so viral protein treatment is likely to alter cellular gene expression and behaviour in a manner conducive to healing. Skin samples were harvested from the lateral thoracic wall of two healthy thoroughbred horses. Equine dermal cells were isolated using a skin explant method and their phenotype assessed by immunofluorescence. Cells were treated with recombinant proteins, with or without inflammatory stimuli. Gene expression was examined using standard and quantitative reverse transcriptase PCR. Cell behaviour was evaluated in a scratch assay. Cultured cells were half vimentin(+ve) fibroblasts and half alpha smooth muscle actin(+ve) and vimentin(+ve) myofibroblasts. VEGF-E increased basal expression of IL-10 mRNA, whereas VEGF-A and collagenase-1 mRNA expression was increased by ovIL-10. In cells exposed to inflammatory stimulus, both treatments dampened tumour necrosis factor mRNA expression, and ovIL-10 exacerbated expression of monocyte chemoattractant protein. Neither viral protein influenced cell migration greatly. This study shows that VEGF-E and ovIL-10 are active on equine dermal cells and exert anti-inflammatory and anti-fibrotic effects that may enhance skin wound healing in horses. © 2016 ESVD and ACVD.

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.

Reciprocal interactions between endothelial cells and macrophages in angiogenic vascular niches

Energy Technology Data Exchange (ETDEWEB)

Baer, Caroline; Squadrito, Mario Leonardo [The Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology Lausanne (EPFL), 1015 Lausanne (Switzerland); Iruela-Arispe, M. Luisa, E-mail: arispe@mcdb.ucla.edu [The Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology Lausanne (EPFL), 1015 Lausanne (Switzerland); Department of Molecular, Cell and Developmental Biology and Molecular Biology Institute, University of California, Los Angeles 90095, CA (United States); De Palma, Michele, E-mail: michele.depalma@epfl.ch [The Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology Lausanne (EPFL), 1015 Lausanne (Switzerland)

2013-07-01

The ability of macrophages to promote vascular growth has been associated with the secretion and local delivery of classic proangiogenic factors (e.g., VEGF-A and proteases). More recently, a series of studies have also revealed that physical contact of macrophages with growing blood vessels coordinates vascular fusion of emerging sprouts. Interestingly, the interactions between macrophages and vascular endothelial cells (ECs) appear to be bidirectional, such that activated ECs also support the expansion and differentiation of proangiogenic macrophages from myeloid progenitors. Here, we discuss recent findings suggesting that dynamic angiogenic vascular niches might also exist in vivo, e.g. in tumors, where sprouting blood vessels and immature myeloid cells like monocytes engage in heterotypic interactions that are required for angiogenesis. Finally, we provide an account of emerging mechanisms of cell-to-cell communication that rely on secreted microvesicles, such as exosomes, which can offer a vehicle for the rapid exchange of molecules and genetic information between macrophages and ECs engaged in angiogenesis. -- Highlights: • Macrophages promote angiogenesis by secreting proangiogenic factors. • Macrophages modulate angiogenesis via cell-to-cell contacts with endothelial cells. • Endothelial cells promote the differentiation of proangiogenic macrophages. • Macrophages and endothelial cells may cooperate to form angiogenic vascular niches.

Reciprocal interactions between endothelial cells and macrophages in angiogenic vascular niches

International Nuclear Information System (INIS)

Baer, Caroline; Squadrito, Mario Leonardo; Iruela-Arispe, M. Luisa; De Palma, Michele

2013-01-01

The ability of macrophages to promote vascular growth has been associated with the secretion and local delivery of classic proangiogenic factors (e.g., VEGF-A and proteases). More recently, a series of studies have also revealed that physical contact of macrophages with growing blood vessels coordinates vascular fusion of emerging sprouts. Interestingly, the interactions between macrophages and vascular endothelial cells (ECs) appear to be bidirectional, such that activated ECs also support the expansion and differentiation of proangiogenic macrophages from myeloid progenitors. Here, we discuss recent findings suggesting that dynamic angiogenic vascular niches might also exist in vivo, e.g. in tumors, where sprouting blood vessels and immature myeloid cells like monocytes engage in heterotypic interactions that are required for angiogenesis. Finally, we provide an account of emerging mechanisms of cell-to-cell communication that rely on secreted microvesicles, such as exosomes, which can offer a vehicle for the rapid exchange of molecules and genetic information between macrophages and ECs engaged in angiogenesis. -- Highlights: • Macrophages promote angiogenesis by secreting proangiogenic factors. • Macrophages modulate angiogenesis via cell-to-cell contacts with endothelial cells. • Endothelial cells promote the differentiation of proangiogenic macrophages. • Macrophages and endothelial cells may cooperate to form angiogenic vascular niches

Citrus Polyphenol Hesperidin Stimulates Production of Nitric Oxide in Endothelial Cells while Improving Endothelial Function and Reducing Inflammatory Markers in Patients with Metabolic Syndrome

Science.gov (United States)

Rizza, Stefano; Muniyappa, Ranganath; Iantorno, Micaela; Kim, Jeong-a; Chen, Hui; Pullikotil, Philomena; Senese, Nicoletta; Tesauro, Manfredi; Lauro, Davide; Cardillo, Carmine

2011-01-01

Context: Hesperidin, a citrus flavonoid, and its metabolite hesperetin may have vascular actions relevant to their health benefits. Molecular and physiological mechanisms of hesperetin actions are unknown. Objective: We tested whether hesperetin stimulates production of nitric oxide (NO) from vascular endothelium and evaluated endothelial function in subjects with metabolic syndrome on oral hesperidin therapy. Design, Setting, and Interventions: Cellular mechanisms of action of hesperetin were evaluated in bovine aortic endothelial cells (BAEC) in primary culture. A randomized, placebo-controlled, double-blind, crossover trial examined whether oral hesperidin administration (500 mg once daily for 3 wk) improves endothelial function in individuals with metabolic syndrome (n = 24). Main Outcome Measure: We measured the difference in brachial artery flow-mediated dilation between placebo and hesperidin treatment periods. Results: Treatment of BAEC with hesperetin acutely stimulated phosphorylation of Src, Akt, AMP kinase, and endothelial NO synthase to produce NO; this required generation of H2O2. Increased adhesion of monocytes to BAEC and expression of vascular cell adhesion molecule-1 in response to TNF-α treatment was reduced by pretreatment with hesperetin. In the clinical study, when compared with placebo, hesperidin treatment increased flow-mediated dilation (10.26 ± 1.19 vs. 7.78 ± 0.76%; P = 0.02) and reduced concentrations of circulating inflammatory biomarkers (high-sensitivity C-reactive protein, serum amyloid A protein, soluble E-selectin). Conclusions: Novel mechanisms for hesperetin action in endothelial cells inform effects of oral hesperidin treatment to improve endothelial dysfunction and reduce circulating markers of inflammation in our exploratory clinical trial. Hesperetin has vasculoprotective actions that may explain beneficial cardiovascular effects of citrus consumption. PMID:21346065

A specific 15-lipoxygenase inhibitor limits the progression and monocyte-macrophage enrichment of hypercholesterolemia-induced atherosclerosis in the rabbit.

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Bocan, T M; Rosebury, W S; Mueller, S B; Kuchera, S; Welch, K; Daugherty, A; Cornicelli, J A

1998-02-01

Oxidant signalling and lipoprotein oxidation may play important roles in atherosclerotic lesion development. Given coincident localization of 15-lipoxygenase (15-LO), stereospecific products of 15-LO and epitopes of modified LDL in atherosclerotic lesions, we hypothesized that inhibition of 15-LO by PD146176, an inhibitor of 15-LO with an IC50 in cells or isolated enzyme of 0.5-0.8 microM, may limit atherosclerotic lesion development through regulation of monocyte-macrophage enrichment. Rabbits exposed to chronic endothelial denudation of the iliac-femoral artery were meal-fed a 0.25% cholesterol (C), 3% peanut oil (PNO), 3% coconut oil (CNO) diet twice daily with and without 175 mg/kg PD146176 for 12 weeks. In a second study, atherosclerotic lesions were pre-established in rabbits through chronic endothelial denudation and meal-fed a 0.5% C, 3% PNO, 3% CNO diet for 9 weeks and a 0% C/fat diet for 6 weeks prior to an 8 week administration of PD146176 at 175 mg/kg, q.d. Plasma total and lipoprotein cholesterol exposure were similar in control and PD146176-treated animals in both studies but PD146176 increased plasma triglyceride exposure 2- to 4-fold. Plasma PD146176 concentrations ranged from 99 to 214 ng/ml at 2 h post-dose. In the progression study, the iliac-femoral monocyte-macrophage area was reduced 71%, cross-sectional lesion area was unchanged and cholesteryl ester (CE) content was reduced 63%. In the regression study, size and macrophage content of iliac-femoral, fibrous plaque-like lesions were decreased 34%, CE content was reduced 19% and gross extent of thoracic aortic lesions were reduced 41%. We conclude that PD146176 can limit monocyte macrophage enrichment of atherosclerotic lesions and can attenuate development of fibrofoamy and fibrous plaque lesions in the absence of changes in plasma total or lipoprotein cholesterol concentrations.

Endothelial cell-derived microparticles induce plasmacytoid dendritic cell maturation: potential implications in inflammatory diseases.

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Angelot, Fanny; Seillès, Estelle; Biichlé, Sabeha; Berda, Yael; Gaugler, Béatrice; Plumas, Joel; Chaperot, Laurence; Dignat-George, Françoise; Tiberghien, Pierre; Saas, Philippe; Garnache-Ottou, Francine

2009-11-01

Increased circulating endothelial microparticles, resulting from vascular endothelium dysfunction, and plasmacytoid dendritic cell activation are both encountered in common inflammatory disorders. The aim of our study was to determine whether interactions between endothelial microparticles and plasmacytoid dendritic cells could contribute to such pathologies. Microparticles generated from endothelial cell lines, platelets or activated T cells were incubated with human plasmacytoid dendritic cells sorted from healthy donor blood or with monocyte-derived dendritic cells. Dendritic cell maturation was evaluated by flow cytometry, cytokine secretion as well as naive T-cell activation and polarization. Labeled microparticles were also used to study cellular interactions. Endothelial microparticles induced plasmacytoid dendritic cell maturation. In contrast, conventional dendritic cells were resistant to endothelial microparticle-induced maturation. In addition to upregulation of co-stimulatory molecules, endothelial microparticle-matured plasmacytoid dendritic cells secreted inflammatory cytokines (interleukins 6 and 8, but no interferon-alpha) and also induced allogeneic naive CD4(+) T cells to proliferate and to produce type 1 cytokines such as interferon-gamma and tumor necrosis factor-alpha. Endothelial microparticle endocytosis by plasmacytoid dendritic cells appeared to be required for plasmacytoid dendritic cell maturation. Importantly, the ability of endothelial microparticles to induce plasmacytoid dendritic cells to mature was specific as microparticles derived from activated T cells or platelets (the major source of circulating microparticules in healthy subjects) did not induce such plasmacytoid dendritic cell maturation. Our data show that endothelial microparticles specifically induce plasmacytoid dendritic cell maturation and production of inflammatory cytokines. This novel activation pathway may be implicated in various inflammatory disorders and

Platelet degranulation and monocyte-platelet complex formation are increased in the acute and convalescent phases after ischaemic stroke or transient ischaemic attack.

LENUS (Irish Health Repository)

McCabe, Dominick J H

2004-06-01

Flow cytometric studies suggest that platelets are activated in ischaemic stroke or transient ischaemic attack (TIA). However, few studies have measured circulating leucocyte-platelet complexes in this patient population. Whole blood flow cytometry was used to quantify the expression of CD62P-, CD63-, and PAC1-binding, and the percentages of leucocyte-platelet complexes in acute (1-27 d, n = 79) and convalescent (79-725 d, n = 70) ischaemic cerebrovascular disease (CVD) patients compared with controls without CVD (n = 27). We performed a full blood count, and measured plasma levels of soluble P-selectin, soluble E-selectin, and von Willebrand factor antigen (VWF:Ag) as additional markers of platelet and\\/or endothelial cell activation. The median percentage CD62P expression and the median percentage monocyte-platelet complexes were higher in both acute and convalescent CVD patients than controls (P <\\/= 0.02). The mean white cell count and mean VWF:Ag levels were significantly elevated in the acute and convalescent phases after ischaemic stroke or TIA (P <\\/= 0.02). Otherwise, there was no significant increase in any other marker of platelet or endothelial activation in CVD patients. There was a positive correlation between the percentage expression of CD62P and the percentages of both neutrophil-platelet and monocyte-platelet complexes in the acute phase, and the percentages of all leucocyte-platelet complexes in the convalescent phase after ischaemic CVD. This study provides evidence for ongoing excessive platelet and\\/or endothelial activation in ischaemic CVD patients despite treatment with antithrombotic therapy.

Monocyte Trafficking to the Brain with Stress and Inflammation: A Novel Axis of Immune-to-Brain Communication that Influences Mood and Behavior

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Eric S Wohleb

2015-01-01

Full Text Available Psychological stressors cause physiological, immunological, and behavioral alterations in humans and rodents that can be maladaptive and negatively affect quality of life. Several lines of evidence indicate that psychological stress disrupts key functional interactions between the immune system and brain that ultimately affects mood and behavior. For example, activation of microglia, the resident innate immune cells of the brain, has been implicated as a key regulator of mood and behavior in the context of prolonged exposure to psychological stress. Emerging evidence implicates a novel neuroimmune circuit involving microglia activation and sympathetic outflow to the peripheral immune system that further reinforces stress-related behaviors by facilitating the recruitment of inflammatory monocytes to the brain. Evidence from various rodent models, including repeated social defeat (RSD, revealed that trafficking of monocytes to the brain promoted the establishment of anxiety-like behaviors following prolonged stress exposure. In addition, new evidence implicates monocyte trafficking from the spleen to the brain as key regulator of recurring anxiety following exposure to prolonged stress. The purpose of this review is to discuss mechanisms that cause stress-induced monocyte re-distribution in the brain and how dynamic interactions between microglia, endothelial cells, and brain macrophages lead to maladaptive behavioral responses.

Endothelial microparticles (EMP in physiology and pathology

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Ewa Sierko

2015-08-01

Full Text Available Endothelial microparticles (EMP are released from endothelial cells (ECs in the process of activation and/or apoptosis. They harbor adhesive molecules, enzymes, receptors and cytoplasmic structures and express a wide range of various constitutive antigens, typical for ECs, at their surface. Under physiological conditions the concentration of EMP in the blood is clinically insignificant. However, it was reported that under pathological conditions EMP concentration in the blood might slightly increase and contribute to blood coagulation, angiogenesis and inflammation. It has been shown that EMP directly and indirectly contribute to the activation of blood coagulation. Endothelial microparticles directly participate in blood coagulation through their surface tissue factor (TF – a major initiator of blood coagulation. Furthermore, EMP exhibit procoagulant potential via expression of negatively charged phospholipids at their surface, which may promote assembly of coagulation enzymes (TF/VII, tenases and prothrombinase complexes, leading to thrombus formation. In addition, they provide a binding surface for coagulation factors: IXa, VIII, Va and IIa. Moreover, it is possible that EMP transfer TF from TF-bearing EMP to activated platelets and monocytes by binding them through adhesion molecules. Also, EMP express von Willebrand factor, which may facilitate platelet aggregation. Apart from their procoagulant properties, it was demonstrated that EMP may express adhesive molecules and metalloproteinases (MMP-2, MMP-9 at their surface and release growth factors, which may contribute to angiogenesis. Additionally, surface presence of C3 and C4 – components of the classical pathway – suggests pro-inflammatory properties of these structures. This article contains a summary of available data on the biology and pathophysiology of endothelial microparticles and their potential role in blood coagulation, angiogenesis and inflammation.

High-intensity Interval training enhances mobilization/functionality of endothelial progenitor cells and depressed shedding of vascular endothelial cells undergoing hypoxia.

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Tsai, Hsing-Hua; Lin, Chin-Pu; Lin, Yi-Hui; Hsu, Chih-Chin; Wang, Jong-Shyan

2016-12-01

Exercise training improves endothelium-dependent vasodilation, whereas hypoxic stress causes vascular endothelial dysfunction. Monocyte-derived endothelial progenitor cells (Mon-EPCs) contribute to vascular repair process by differentiating into endothelial cells. This study investigates how high-intensity interval (HIT) and moderate-intensity continuous (MCT) exercise training affect circulating Mon-EPC levels and EPC functionality under hypoxic condition. Sixty healthy sedentary males were randomized to engage in either HIT (3-min intervals at 40 and 80 % VO 2max for five repetitions, n = 20) or MCT (sustained 60 % VO 2max , n = 20) for 30 min/day, 5 days/week for 6 weeks, or to a control group (CTL) that did not received exercise intervention (n = 20). Mon-EPC characteristics and EPC functionality under hypoxic exercise (HE, 100 W under 12 % O 2 ) were determined before and after HIT, MCT, and CTL. The results demonstrated that after the intervention, the HIT group exhibited larger improvements in VO 2peak , estimated peak cardiac output (Q C ), and estimated peak perfusions of frontal cerebral lobe (Q FC ) and vastus lateralis (Q VL ) than the MCT group. Furthermore, HIT (a) increased circulating CD14 ++ /CD16 - /CD34 + /KDR + (Mon-1 EPC) and CD14 ++ /CD16 + /CD34 + /KDR + (Mon-2 EPC) cell counts, (b) promoted the migration and tube formation of EPCs, (c) diminished the shedding of endothelial (CD34 - /KDR + /phosphatidylserine + ) cells, and (d) elevated plasma nitrite plus nitrate, stromal cell-derived factor-1, matrix metalloproteinase-9, and vascular endothelial growth factor-A concentrations at rest or following HE, compared to those of MCT. In addition, Mon-1 and -2 EPC counts were directly related to VO 2peak and estimated peak Q C , Q FC , and Q VL . HIT is superior to MCT for improving hemodynamic adaptation and Mon-EPC production. Moreover, HIT effectively enhances EPC functionality and suppresses endothelial injury undergoing hypoxia.

Progranulin Is a Chemoattractant for Microglia and Stimulates Their Endocytic Activity

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Pickford, Fiona; Marcus, Jacob; Camargo, Luiz Miguel; Xiao, Qiurong; Graham, Danielle; Mo, Jan-Rung; Burkhardt, Matthew; Kulkarni, Vinayak; Crispino, Jamie; Hering, Heike; Hutton, Michael

2011-01-01

Mutations resulting in progranulin haploinsufficiency cause disease in patients with a subset of frontotemporal lobar degeneration; however, the biological functions of progranulin in the brain remain unknown. To address this subject, the present study initially assessed changes in gene expression and cytokine secretion in rat primary cortical neurons treated with progranulin. Molecular pathways enriched in the progranulin gene set included cell adhesion and cell motility pathways and pathways involved in growth and development. Secretion of cytokines and several chemokines linked to chemoattraction but not inflammation were also increased from progranulin-treated primary neurons. Therefore, whether progranulin is involved in recruitment of immune cells in the brain was investigated. Localized lentiviral expression of progranulin in C57BL/6 mice resulted in an increase of Iba1-positive microglia around the injection site. Moreover, progranulin alone was sufficient to promote migration of primary mouse microglia in vitro. Primary microglia and C4B8 cells demonstrated more endocytosis of amyloid β1-42 when treated with progranulin. These data demonstrate that progranulin acts as a chemoattractant in the brain to recruit or activate microglia and can increase endocytosis of extracellular peptides such as amyloid β. PMID:21224065

Folic acid is a potent chemoattractant of free-living amoebae in a new and amazing species of protist, Vahlkampfia sp.

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Maeda, Yasuo; Mayanagi, Taira; Amagai, Aiko

2009-03-01

Folic acid (folate; vitamin Bc) is well recognized as essential for the proper metabolism of the essential amino acid methionine as well as for the synthesis of adenine and thymine. A folate deficiency has been Implicated in a wide variety of disorders from Alzheimer's disease to depression and neural tube defects. In the cellular slime molds, including Dictyostelium, vegetative growth-phase cells are known to chemotactically move toward folate that is secreted by bacterial food sources such as Escherichia coli. Intracellular folate signal transductlon, including G proteins, Ca(2+)channels, and the PIP3 pathway, has been reported in D. discoideum. To our surprise, the genuine chemoattractant(s) of free-living protozoan amoebae have remained to be determined, possibly because of lack of a pertinent method for assaying chemotaxis. We recently isolated a primitive free-living amoeba from the soil of Costa Rica and identified it as a new species of the genus Vahlkampfia belonging to Subclass Gymnamoebia, which includes Entamoeba and Acanthamoeba. The amoebae can grow and multiply quite rapidly, engulfing nearby bacteria such as E. coli. Importantly, we have demonstrated here using a quite simple but finely designed chemotaxis assay that the Vahlkampfia amoebae exhibit chemotaxis toward higher folate concentrations. Riboflavin and cyanocobalamin were also found to serve as positive chemoattractants. Among these chemoattractants, folate is of particular importance because its function seems to be evolutionarily conserved as a potent chemoattractant of amoeboid cells in a wide range of organisms as well as in the Protista and cellular slime molds.

Monocyte adhesion induced by multi-walled carbon nanotubes and palmitic acid in endothelial cells and alveolar-endothelial co-cultures

DEFF Research Database (Denmark)

Cao, Yi; Roursgaard, Martin; Jacobsen, Nicklas Raun

2016-01-01

Free palmitic acid (PA) is a potential pro-atherogenic stimulus that may aggravate particle-mediated cardiovascular health effects. We hypothesized that the presence of PA can aggravate oxidative stress and endothelial activation induced by multi-walled carbon nanotube (MWCNT) exposure in vitro. We...... measured in the lower chamber on HUVECs and THP-1 cells. The exposure to MWCNTs, including a short (NM400) and long (NM402) type of entangled fibers, was associated with elevated levels of reactive oxygen species as well as a decrease in the intracellular glutathione concentration in HUVEC and A549...

Monocyte transferrin-iron uptake in hereditary hemochromatosis

International Nuclear Information System (INIS)

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

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

Caffeic acid attenuates the inflammatory stress induced by glycated LDL in human endothelial cells by mechanisms involving inhibition of AGE-receptor, oxidative, and endoplasmic reticulum stress.

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Toma, Laura; Sanda, Gabriela M; Niculescu, Loredan S; Deleanu, Mariana; Stancu, Camelia S; Sima, Anca V

2017-09-10

Type 2 diabetes mellitus is a worldwide epidemic and its atherosclerotic complications determine the high morbidity and mortality of diabetic patients. Caffeic acid (CAF), a phenolic acid present in normal diets, is known for its antioxidant properties. The aim of this study was to investigate CAF's anti-inflammatory properties and its mechanism of action, using cultured human endothelial cells (HEC) incubated with glycated low-density lipoproteins (gLDL). Levels of the receptor for advanced glycation end-products (RAGE), inflammatory stress markers (C reactive protein, CRP; vascular cell adhesion molecule-1, VCAM-1; monocyte chemoattractant protein-1, MCP-1), and oxidative stress and endoplasmic reticulum stress (ERS) markers were evaluated in gLDL-exposed HEC, in the presence/absence of CAF. RAGE silencing or blocking, specific inhibitors for oxidative stress (apocynin, N-acetyl-cysteine), and ERS (salubrinal) were used. The results showed that: (i) gLDL induced CRP synthesis and secretion through mechanisms involving NADPH oxidase-dependent oxidative stress and ERS in HEC; (ii) gLDL-RAGE interaction, oxidative stress, and ERS stimulated the secretion of VCAM-1 and MCP-1 in HEC; and (iii) CAF reduced the secretion of CRP, VCAM-1, and MCP-1 in gLDL-exposed HEC by inhibiting RAGE expression, oxidative stress, and ERS. In conclusion, CAF might be a promising alternative to ameliorate a wide spectrum of disorders due to its complex mechanisms of action resulting in anti-inflammatory and antioxidative properties. © 2017 BioFactors, 43(5):685-697, 2017. © 2017 International Union of Biochemistry and Molecular Biology.

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.

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.

Angiogenesis in mucous retention cyst: a human in vivo-like model of endothelial cell differentiation in mucous substrate.

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Swelam, Wael; Ida-Yonemochi, Hiroko; Saku, Takashi

2005-01-01

Mucous retention cysts contain a mucous pool in the lumina, in which pure angiogenic processes are occasionally observed. By using this unique human material, our aim was to understand the in vivo angiogenic process. Fifteen surgical tissue samples of mucous retention cysts of the lip were examined for expression of vascular endothelial markers and extracellular matrix molecules by immunohistochemistry and in situ hybridization (ISH). Endothelial cells forming new vascular channels showed immunopositivities for CD31, CD34, vascular endothelial growth factor (VEGF), and von Willebrand factor (vWF). These newly formed capillaries were surrounded by tenascin-positive matrices and further by a dense infiltration of CD68-positive cells with foamy to epitheloid appearances. Some of these cells were simultaneously positive for CD34, VEGF, and one of its receptors, Flk-1, and they showed definite mRNA as well as protein signals for tenascin. In addition, these cells often tended to be aligned, which suggested tubule formation. The results suggest that monocyte/macrophage lineage cells are a major source for endothelial cells at least in mucous retention cysts and that tenascin produced by those cells plays an important role in differentiation of endothelial cells.

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

Adverse fibrosis in the aging heart depends on signaling between myeloid and mesenchymal cells; role of inflammatory fibroblasts.

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Cieslik, Katarzyna A; Trial, JoAnn; Crawford, Jeffrey R; Taffet, George E; Entman, Mark L

2014-05-01

Aging has been associated with adverse fibrosis. Here we formulate a new hypothesis and present new evidence that unresponsiveness of mesenchymal stem cells (MSC) and fibroblasts to transforming growth factor beta (TGF-β), due to reduced expression of TGF-β receptor I (TβRI), provides a foundation for cardiac fibrosis in the aging heart via two mechanisms. 1) TGF-β promotes expression of Nanog, a transcription factor that retains MSC in a primitive state. In MSC derived from the aging heart, Nanog expression is reduced and therefore MSC gradually differentiate and the number of mesenchymal fibroblasts expressing collagen increases. 2) As TGF-β signaling pathway components negatively regulate transcription of monocyte chemoattractant protein-1 (MCP-1), a reduced expression of TβRI prevents aging mesenchymal cells from shutting down their own MCP-1 expression. Elevated MCP-1 levels that originated from MSC attract transendothelial migration of mononuclear leukocytes from blood to the tissue. MCP-1 expressed by mesenchymal fibroblasts promotes further migration of monocytes and T lymphocytes away from the endothelial barrier and supports the monocyte transition into macrophages and finally into myeloid fibroblasts. Both myeloid and mesenchymal fibroblasts contribute to fibrosis in the aging heart via collagen synthesis. This article is part of a Special Issue entitled "Myocyte-Fibroblast Signalling in Myocardium ". © 2013. Published by Elsevier Ltd. All rights reserved.

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.

Myelosuppression of Thrombocytes and Monocytes Is Associated with a Lack of Synergy between Chemotherapy and Anti-VEGF Treatment

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Patrick Starlinger

2011-05-01

Full Text Available Purpose: Chemotherapeutic agents that have shown improved patient outcome when combined with anti-vascular endothelial growth factor (VEGF therapy were recently identified to induce the mobilization of proangiogenic Tie-2-expressing monocytes (TEMs and endothelial progenitor cells (EPCs by platelet release of stromal cell-derived factor 1α (SDF-1α. VEGF blockade was found to counteract cell mobilization. We aimed to determine why agents like gemcitabine do not elicit TEM and EPC recruitment and may therefore lack synergy with anti-VEGF therapy. Experimental Design: Locally advanced pancreatic cancer patients (n = 20 were monitored during 16 weeks of neoadjuvant therapy. Treatment was based on gemcitabine with or without the addition of bevacizumab. Blood levels of proangiogenic cell populations and angiogenesis factors were determined in 2-week intervals. Results: The lack of EPC mobilization during gemcitabine therapy was associated with severe thrombocytopenia and reduced SDF-1α blood concentrations. Furthermore, myelosuppression by gemcitabine correlated significantly with loss of TEMs. With respect to angiogenic factors stored and released by platelets, plasma levels of the angiogenesis inhibitor thrombospondin 1 (TSP-1 were selectively decreased and correlated significantly with thrombocytopenia in response to gemcitabine therapy. Conclusions: A thorough literature screen identified thrombocytopenia as a common feature of chemotherapeutic agents that lack synergy with anti-VEGF treatment. Our results on gemcitabine therapy indicate that myelosuppression (in particular, with respect to thrombocytes and monocytes interferes with the mobilization of proangiogenic cell types targeted by bevacizumab and may further counteract antiangiogenic therapy by substantially reducing the angiogenesis inhibitor TSP-1.

Mononuclear Phagocyte-Derived Microparticulate Caspase-1 Induces Pulmonary Vascular Endothelial Cell Injury.

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Srabani Mitra

Full Text Available Lung endothelial cell apoptosis and injury occurs throughout all stages of acute lung injury (ALI/ARDS and impacts disease progression. Lung endothelial injury has traditionally been focused on the role of neutrophil trafficking to lung vascular integrin receptors induced by proinflammatory cytokine expression. Although much is known about the pathogenesis of cell injury and death in ALI/ARDS, gaps remain in our knowledge; as a result of which there is currently no effective pharmacologic therapy. Enzymes known as caspases are essential for completion of the apoptotic program and secretion of pro-inflammatory cytokines. We hypothesized that caspase-1 may serve as a key regulator of human pulmonary microvascular endothelial cell (HPMVEC apoptosis in ALI/ARDS. Our recent experiments confirm that microparticles released from stimulated monocytic cells (THP1 induce lung endothelial cell apoptosis. Microparticles pretreated with the caspase-1 inhibitor, YVAD, or pan-caspase inhibitor, ZVAD, were unable to induce cell death of HPMVEC, suggesting the role of caspase-1 or its substrate in the induction of HPMVEC cell death. Neither un-induced microparticles (control nor direct treatment with LPS induced apoptosis of HPMVEC. Further experiments showed that caspase-1 uptake into HPMVEC and the induction of HPMVEC apoptosis was facilitated by caspase-1 interactions with microparticulate vesicles. Altering vesicle integrity completely abrogated apoptosis of HPMVEC suggesting an encapsulation requirement for target cell uptake of active caspase-1. Taken together, we confirm that microparticle centered caspase-1 can play a regulator role in endothelial cell injury.

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...

A knockout mutation of a constitutive GPCR in Tetrahymena decreases both G-protein activity and chemoattraction.

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Thomas J Lampert

Full Text Available Although G-protein coupled receptors (GPCRs are a common element in many chemosensory transduction pathways in eukaryotic cells, no GPCR or regulated G-protein activity has yet been shown in any ciliate. To study the possible role for a GPCR in the chemoresponses of the ciliate Tetrahymena, we have generated a number of macronuclear gene knockouts of putative GPCRs found in the Tetrahymena Genome database. One of these knockout mutants, called G6, is a complete knockout of a gene that we call GPCR6 (TTHERM_00925490. Based on sequence comparisons, the Gpcr6p protein belongs to the Rhodopsin Family of GPCRs. Notably, Gpcr6p shares highest amino acid sequence homologies to GPCRs from Paramecium and several plants. One of the phenotypes of the G6 mutant is a decreased responsiveness to the depolarizing ions Ba²⁺ and K⁺, suggesting a decrease in basal excitability (decrease in Ca²⁺ channel activity. The other major phenotype of G6 is a loss of chemoattraction to lysophosphatidic acid (LPA and proteose peptone (PP, two known chemoattractants in Tetrahymena. Using microsomal [³⁵S]GTPγS binding assays, we found that wild-type (CU427 have a prominent basal G-protein activity. This activity is decreased to the same level by pertussis toxin (a G-protein inhibitor, addition of chemoattractants, or the G6 mutant. Since the basal G-protein activity is decreased by the GPCR6 knockout, it is likely that this gene codes for a constitutively active GPCR in Tetrahymena. We propose that chemoattractants like LPA and PP cause attraction in Tetrahymena by decreasing the basal G-protein stimulating activity of Gpcr6p. This leads to decreased excitability in wild-type and longer runs of smooth forward swimming (less interrupted by direction changes towards the attractant. Therefore, these attractants may work as inverse agonists through the constitutively active Gpcr6p coupled to a pertussis-sensitive G-protein.

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.

Myelosuppression of Thrombocytes and Monocytes Is Associated with a Lack of Synergy between Chemotherapy and Anti-VEGF Treatment1

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Starlinger, Patrick; Brugger, Philipp; Schauer, Dominic; Sommerfeldt, Silvia; Tamandl, Dietmar; Kuehrer, Irene; Schoppmann, Sebastian F; Gnant, Michael; Brostjan, Christine

2011-01-01

Purpose Chemotherapeutic agents that have shown improved patient outcome when combined with anti-vascular endothelial growth factor (VEGF) therapy were recently identified to induce the mobilization of proangiogenic Tie-2-expressing monocytes (TEMs) and endothelial progenitor cells (EPCs) by platelet release of stromal cell-derived factor 1α (SDF-1α). VEGF blockade was found to counteract cell mobilization. We aimed to determine why agents like gemcitabine do not elicit TEM and EPC recruitment and may therefore lack synergy with anti-VEGF therapy. Experimental Design Locally advanced pancreatic cancer patients (n = 20) were monitored during 16 weeks of neoadjuvant therapy. Treatment was based on gemcitabine with or without the addition of bevacizumab. Blood levels of proangiogenic cell populations and angiogenesis factors were determined in 2-week intervals. Results The lack of EPC mobilization during gemcitabine therapy was associated with severe thrombocytopenia and reduced SDF-1α blood concentrations. Furthermore, myelosuppression by gemcitabine correlated significantly with loss of TEMs. With respect to angiogenic factors stored and released by platelets, plasma levels of the angiogenesis inhibitor thrombospondin 1 (TSP-1) were selectively decreased and correlated significantly with thrombocytopenia in response to gemcitabine therapy. Conclusions A thorough literature screen identified thrombocytopenia as a common feature of chemotherapeutic agents that lack synergy with anti-VEGF treatment. Our results on gemcitabine therapy indicate that myelosuppression (in particular, with respect to thrombocytes and monocytes) interferes with the mobilization of proangiogenic cell types targeted by bevacizumab and may further counteract antiangiogenic therapy by substantially reducing the angiogenesis inhibitor TSP-1. PMID:21532882

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.)

Effect of peritoneal dialysis fluid containing osmo-metabolic agents on human endothelial cells

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Bonomini M

2016-11-01

Full Text Available Mario Bonomini,1,2 Sara Di Silvestre,3,4 Pamela Di Tomo,3,4 Natalia Di Pietro,2,4 Domitilla Mandatori,3,4 Lorenzo Di Liberato,1 Vittorio Sirolli,1,2 Francesco Chiarelli,2,4 Cesare Indiveri,5 Assunta Pandolfi,3,4 Arduino Arduini6 1Unit of Nephrology and Dialysis, 2Department of Medicine and Aging Sciences, 3Department of Medical, Oral and Biotechnological Sciences, 4Aging Research Center and Translational Medicine, CeSI-MeT, University “G. d’Annunzio”, Chieti-Pescara, 5Department DiBEST (Biologia, Ecologia, Scienze della Terra, Unit of Biochemistry and Molecular Biotechnology, University of Calabria, Arcavacata di Rende CS, Italy; 6CoreQuest, Manno, Switzerland Background: The use of glucose as the only osmotic agent in peritoneal dialysis (PD solutions (PDSs is believed to exert local (peritoneal and systemic detrimental actions, particularly in diabetic PD patients. To improve peritoneal biocompatibility, we have developed more biocompatible PDSs containing xylitol and carnitine along with significantly less amounts of glucose and have tested them in cultured Human Vein Endothelial Cells (HUVECs obtained from the umbilical cords of healthy (C and gestational diabetic (GD mothers. Methods: Primary C- and GD-HUVECs were treated for 72 hours with our PDSs (xylitol 0.7% and 1.5%, whereas carnitine and glucose were fixed at 0.02% and 0.5%, respectively and two glucose-based PDSs (glucose 1.36% or 2.27%. We examined their effects on endothelial cell proliferation (cell count, viability (3-(4,5-dimethylthiazolyl-2-2,5-diphenyltetrazolium bromide assay, intracellular nitro-oxidative stress (peroxynitrite levels, Vascular Cell Adhesion Molecule-1 and Intercellular Adhesion Molecule-1 membrane exposure (flow cytometry, and HUVEC-monocyte interactions (U937 adhesion assay. Results: Compared to glucose-based PDSs, our in vitro studies demonstrated that the tested PDSs did not change the proliferative potential both in C- and GD-HUVECs. Moreover, our

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

Increased endothelial and macrophage markers are associated with disease severity and mortality in scrub typhus.

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Otterdal, Kari; Janardhanan, Jeshina; Astrup, Elisabeth; Ueland, Thor; Prakash, John A J; Lekva, Tove; Abraham, O C; Thomas, Kurien; Damås, Jan Kristian; Mathews, Prasad; Mathai, Dilip; Aukrust, Pål; Varghese, George M

2014-11-01

Scrub typhus is endemic in the Asia-Pacific region. Mortality is high even with treatment, and further knowledge of the immune response during this infection is needed. This study was aimed at comparing plasma levels of monocyte/macrophage and endothelial related inflammatory markers in patients and controls in South India and to explore a possible correlation to disease severity and clinical outcome. Plasma levels of ALCAM, VCAM-1, sCD163, sCD14, YKL-40 and MIF were measured in scrub typhus patients (n = 129), healthy controls (n = 31) and in infectious disease controls (n = 31), both in the acute phase and after recovery, by enzyme immunoassays. Patients had markedly elevated levels of all mediators in the acute phase, differing from both healthy and infectious disease controls. During follow-up levels of ALCAM, VCAM-1, sCD14 and YKL-40 remained elevated compared to levels in healthy controls. High plasma ALCAM, VCAM-1, sCD163, sCD14, and MIF, and in particular YKL-40 were all associated with disease severity and ALCAM, sCD163, MIF and especially YKL-40, were associated with mortality. Our findings show that scrub typhus is characterized by elevated levels of monocyte/macrophage and endothelial related markers. These inflammatory markers, and in particular YKL-40, may contribute to disease severity and clinical outcome. Copyright © 2014 The British Infection Association. Published by Elsevier Ltd. All rights reserved.

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

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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.

Endothelial cell activation, oxidative stress and inflammation induced by a panel of metal-based nanomaterials

DEFF Research Database (Denmark)

Danielsen, Pernille Høgh; Cao, Yi; Roursgaard, Martin

2015-01-01

The importance of composition, size, crystal structure, charge and coating of metal-based nanomaterials (NMs) were evaluated in human umbilical vein endothelial cells (HUVECs) and/or THP-1 monocytic cells. Biomarkers of oxidative stress and inflammation were assessed because they are important...... in the development of cardiovascular diseases. The NMs used were five TiO2 NMs with different charge, size and crystal structure, coated and uncoated ZnO NMs and Ag which were tested in a wide concentration range. There were major differences between the types of NMs; exposure to ZnO and Ag resulted in cytotoxicity...... and increased gene expression levels of HMOX1 and IL8. The intracellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1(VCAM-1) expression were highest in TiO2 NM-exposed cells. There was increased adhesion of THP-1 monocytic cells onto HUVECs with Ag exposure. None of the NMs increased...

Long-term, regular remote ischemic preconditioning improves endothelial function in patients with coronary heart disease

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Liang, Y.; Li, Y.P.; He, F.; Liu, X.Q.; Zhang, J.Y. [Department of Cardiology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou (China)

2015-04-28

Remote ischemic preconditioning (RIPre) can prevent myocardial injury. The purpose of this study was to assess the beneficial effects of long-term regular RIPre on human arteries. Forty patients scheduled for coronary artery bypass graft (CABG) surgery were assigned randomly to a RIPre group (n=20) or coronary heart disease (CHD) group (n=20). Twenty patients scheduled for mastectomy were enrolled as a control group. RIPre was achieved by occluding arterial blood flow 5 min with a mercury sphygmomanometer followed by a 5-min reperfusion period, and this was repeated 4 times. The RIPre procedure was repeated 3 times a day for 20 days. In all patients, arterial fragments discarded during surgery were collected to evaluate endothelial function by flow-mediated dilation (FMD), CD34{sup +} monocyte count, and endothelial nitric oxide synthase (eNOS expression). Phosphorylation levels of STAT-3 and Akt were also assayed to explore the underlying mechanisms. Compared with the CHD group, long-term regular RIPre significantly improved FMD after 20 days (8.5±2.4 vs 4.9±4.2%, P<0.05) and significantly reduced troponin after CABG surgery (0.72±0.31 and 1.64±0.19, P<0.05). RIPre activated STAT-3 and increased CD34{sup +} endothelial progenitor cell counts found in arteries. Long-term, regular RIPre improved endothelial function in patients with CHD, possibly due to STAT-3 activation, and this may have led to an increase in endothelial progenitor cells.

Heme Oxygenase-1 Inhibits HLA Class I Antibody-Dependent Endothelial Cell Activation.

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Eva Zilian

Full Text Available Antibody-mediated rejection (AMR is a key limiting factor for long-term graft survival in solid organ transplantation. Human leukocyte antigen (HLA class I (HLA I antibodies (Abs play a major role in the pathogenesis of AMR via their interactions with HLA molecules on vascular endothelial cells (ECs. The antioxidant enzyme heme oxygenase (HO-1 has anti-inflammatory functions in the endothelium. As complement-independent effects of HLA I Abs can activate ECs, it was the goal of the current study to investigate the role of HO-1 on activation of human ECs by HLA I Abs. In cell cultures of various primary human macro- and microvascular ECs treatment with monoclonal pan- and allele-specific HLA I Abs up-regulated the expression of inducible proinflammatory adhesion molecules and chemokines (vascular cell adhesion molecule-1 [VCAM-1], intercellular cell adhesion molecule-1 [ICAM-1], interleukin-8 [IL-8] and monocyte chemotactic protein 1 [MCP-1]. Pharmacological induction of HO-1 with cobalt-protoporphyrin IX reduced, whereas inhibition of HO-1 with either zinc-protoporphyrin IX or siRNA-mediated knockdown increased HLA I Ab-dependent up-regulation of VCAM-1. Treatment with two carbon monoxide (CO-releasing molecules, which liberate the gaseous HO product CO, blocked HLA I Ab-dependent EC activation. Finally, in an in vitro adhesion assay exposure of ECs to HLA I Abs led to increased monocyte binding, which was counteracted by up-regulation of HO-1. In conclusion, HLA I Ab-dependent EC activation is modulated by endothelial HO-1 and targeted induction of this enzyme may be a novel therapeutic approach for the treatment of AMR in solid organ transplantation.

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.

Purification and characterization of a chemoattractant from electric shock-induced earthworm secretion, its receptor binding, and signal transduction through the vomeronasal system of garter snakes.

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Jiang, X C; Inouchi, J; Wang, D; Halpern, M

1990-05-25

Following shocks with low voltage electric current, earthworms, Lumbricus terrestris, secrete a yellow mucus that has alarm properties for conspecifics and chemoattractive properties for garter snakes, Thamnophis sirtalis. A proteinaceous chemoattractant for garter snakes has been isolated and purified to homogeneity from such secretions by means of permeation chromatography and semipreparative nondenaturing polyacrylamide gel electrophoresis. The purified protein is highly attractive to garter snakes; it loses its activity after proteolytic digestion. It is a glycoprotein consisting of a single polypeptide chain with an NH2-terminal alanine. This chemoattractant has a minimum molecular mass of 15.4 kDa calculated from its amino acid and carbohydrate contents and an apparent molecular mass of about 20 kDa as estimated from sodium dodecyl sulfate-polyacrylamide gel electrophoresis. It has a pI of about 4.0, and it binds wheat germ agglutinin but not concanavalin A. This chemoattractant shows a protein to carbohydrate ratio of 2.0 +/- 0.08 (n = 5) and a ratio of total sugar to amino sugar of 1.9 +/- 0.08 (n = 3). The sequence of its NH2-terminal 15 amino acid residues has been determined. Studies were also conducted on the chemosignal transduction through the vomeronasal sensory system of the garter snake. Dot blot analysis showed that the purified chemoattractant bound to snake vomeronasal sensory epithelial membrane fractions. It did not bind to membrane extracts of the nonsensory epithelium of the vomeronasal mushroom body. The chemoattractant also bound specifically to vomeronasal sensory epithelial membrane in a reversible and saturable fashion with Kd and Bmax values of about 0.3 microM and 0.4 nmol/mg of protein, respectively. In electrophysiological studies, the chemoattractant applied to the vomeronasal epithelium caused an increase in firing rate of individual neurons in the accessory olfactory bulb of garter snakes, the projection site for vomeronasal

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

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

Science.gov (United States)

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.

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.

Association of Canine Osteosarcoma and Monocyte Phenotype and Chemotactic Function.

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Tuohy, J L; Lascelles, B D X; Griffith, E H; Fogle, J E

2016-07-01

Monocytes/macrophages are likely key cells in immune modulation in dogs with osteosarcoma (OSA). Increased peripheral monocyte counts are negatively correlated with shorter disease-free intervals in dogs with OSA. Understanding the monocyte/macrophage's modulatory role in dogs with OSA can direct further studies in immunotherapy development for OSA. That OSA evades the immune response by down-regulating monocyte chemokine receptor expression and migratory function, and suppresses host immune responses. Eighteen dogs with OSA that have not received definitive treatment and 14 healthy age-matched controls Clinical study-expression of peripheral blood monocyte cell surface receptors, monocyte mRNA expression and cytokine secretion, monocyte chemotaxis, and survival were compared between clinical dogs with OSA and healthy control dogs. Cell surface expression of multiple chemokine receptors is significantly down-regulated in peripheral blood monocytes of dogs with OSA. The percentage expression of CCR2 (median 58%, range 2-94%) and CXCR2 expression (median 54%, range 2-92%) was higher in control dogs compared to dogs with OSA (CCR2 median 29%, range 3-45%, P = 0.0006; CXCR2 median 23%, range 0.2-52%, P = 0.0007). Prostaglandin E2 (PGE2 ) (OSA, median 347.36 pg/mL, range 103.4-1268.5; control, 136.23 pg/mL, range 69.93-542.6, P = .04) and tumor necrosis factor-alpha (TNF-α) (P = .02) levels are increased in OSA monocyte culture supernatants compared to controls. Peripheral blood monocytes of dogs with OSA exhibit decreased chemotactic function when compared to control dogs (OSA, median 1.2 directed to random migration, range 0.8-1.25; control, 1.6, range of 0.9-1.8, P = .018). Dogs with OSA have decreased monocyte chemokine receptor expression and monocyte chemotaxis, potential mechanisms by which OSA might evade the immune response. Reversal of monocyte dysfunction using immunotherapy could improve survival in dogs with OSA. Copyright © 2016 The Authors. Journal of

Two weeks taurine supplementation reverses endothelial dysfunction in young male type 1 diabetics.

LENUS (Irish Health Repository)

Moloney, Michael A

2010-10-01

Type 1 diabetics have a well-recognised risk of accelerated cardiovascular disease. Even in the absence of clinical signs there are detectable abnormalities of conduit vessel function. Our group has previously reported reversal of endothelial dysfunction in diabetics with pravastatin. In young asymptomatic smokers, taurine supplementation has a beneficial impact on macrovascular function, assessed by FMD, and shows an up-regulation of nitric oxide from monocyte-endothelial cell interactions. We hypothesise that taurine supplementation reverses early endothelial abnormalities in young male type 1 diabetics, as assessed by applanation tonometry, brachial artery ultrasound and laser Doppler fluximetry. Asymptomatic, male diabetics (n=9) were scanned prior to treatment and then randomised in a double-blind cross-over fashion to receive either 2 weeks placebo or taurine. Control patients (n=10) underwent a baseline scan. Assessed diabetics had detectable, statistically significant abnormalities when compared with controls, in both arterial stiffness (augmentation index) and brachial artery reactivity (FMD). Both of these parameters were returned to control levels with 2 weeks taurine supplementation. In conclusion, 2 weeks taurine supplementation reverses early, detectable conduit vessel abnormalities in young male diabetics. This may have important implications in the long-term treatment of diabetic patients and their subsequent progression towards atherosclerotic disease.

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.

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.

Contribution of endothelial progenitors and proangiogenic hematopoietic cells to vascularization of tumor and ischemic tissue

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Kopp, Hans-Georg; Ramos, Carlos A.; Rafii, Shahin

2010-01-01

Purpose of review During the last several years, a substantial amount of evidence from animal as well as human studies has advanced our knowledge of how bone marrow derived cells contribute to neoangiogenesis. In the light of recent findings, we may have to redefine our thinking of endothelial cells as well as of perivascular mural cells. Recent findings Inflammatory hematopoietic cells, such as macrophages, have been shown to promote neoangiogenesis during tumor growth and wound healing. Dendritic cells, B lymphocytes, monocytes, and other immune cells have also been found to be recruited to neoangiogenic niches and to support neovessel formation. These findings have led to the concept that subsets of hematopoietic cells comprise proangiogenic cells that drive adult revascularization processes. While evidence of the importance of endothelial progenitor cells in adult vasculogenesis increased further, the role of these comobilized hematopoietic cells has been intensely studied in the last few years. Summary Angiogenic factors promote mobilization of vascular endothelial growth factor receptor 1-positive hematopoietic cells through matrix metalloproteinase-9 mediated release of soluble kit-ligand and recruit these proangiogenic cells to areas of hypoxia, where perivascular mural cells present stromal-derived factor 1 (CXCL-12) as an important retention signal. The same factors are possibly involved in mobilization of vascular endothelial growth factor receptor 2-positive endothelial precursors that may participate in neovessel formation. The complete characterization of mechanisms, mediators and signaling pathways involved in these processes will provide novel targets for both anti and proangiogenic therapeutic strategies. PMID:16567962

Bone morphogenic protein 4 produced in endothelial cells by oscillatory shear stress stimulates an inflammatory response

Science.gov (United States)

Sorescu, George P.; Sykes, Michelle; Weiss, Daiana; Platt, Manu O.; Saha, Aniket; Hwang, Jinah; Boyd, Nolan; Boo, Yong C.; Vega, J. David; Taylor, W. Robert;

Anti-Inflammatory Activity of Marine Ovothiol A in an In Vitro Model of Endothelial Dysfunction Induced by Hyperglycemia

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Immacolata Castellano

2018-01-01

Full Text Available Chronic hyperglycemia is associated with oxidative stress and vascular inflammation, both leading to endothelial dysfunction and cardiovascular disease that can be weakened by antioxidant/anti-inflammatory molecules in both healthy and diabetic subjects. Among natural molecules, ovothiol A, produced in sea urchin eggs to protect eggs/embryos from the oxidative burst at fertilization and during development, has been receiving increasing interest for its use as an antioxidant. Here, we evaluated the potential antioxidative/anti-inflammatory effect of purified ovothiol A in an in vitro cellular model of hyperglycemia-induced endothelial dysfunction employing human umbilical vein endothelial cells (HUVECs from women affected by gestational diabetes (GD and from healthy mothers. Ovothiol A was rapidly taken up by both cellular systems, resulting in increased glutathione values in GD-HUVECs, likely due to the formation of reduced ovothiol A. In tumor necrosis factor-α-stimulated cells, ovothiol A induced a downregulation of adhesion molecule expression and decrease in monocyte-HUVEC interaction. This was associated with a reduction in reactive oxygen and nitrogen species and an increase in nitric oxide bioavailability. These results point to the potential antiatherogenic properties of the natural antioxidant ovothiol A and support its therapeutic potential in pathologies related to cardiovascular diseases associated with oxidative/inflammatory stress and endothelial dysfunction.

Endothelial RIG-I activation impairs endothelial function

International Nuclear Information System (INIS)

Asdonk, Tobias; Motz, Inga; Werner, Nikos; Coch, Christoph; Barchet, Winfried; Hartmann, Gunther; Nickenig, Georg; Zimmer, Sebastian

2012-01-01

Highlights: ► RIG-I activation impairs endothelial function in vivo. ► RIG-I activation alters HCAEC biology in vitro. ► EPC function is affected by RIG-I stimulation in vitro. -- Abstract: Background: Endothelial dysfunction is a crucial part of the chronic inflammatory atherosclerotic process and is mediated by innate and acquired immune mechanisms. Recent studies suggest that pattern recognition receptors (PRR) specialized in immunorecognition of nucleic acids may play an important role in endothelial biology in a proatherogenic manner. Here, we analyzed the impact of endothelial retinoic acid inducible gene I (RIG-I) activation upon vascular endothelial biology. Methods and results: Wild type mice were injected intravenously with 32.5 μg of the RIG-ligand 3pRNA (RNA with triphosphate at the 5′end) or polyA control every other day for 7 days. In 3pRNA-treated mice, endothelium-depended vasodilation was significantly impaired, vascular oxidative stress significantly increased and circulating endothelial microparticle (EMP) numbers significantly elevated compared to controls. To gain further insight in RIG-I dependent endothelial biology, cultured human coronary endothelial cells (HCAEC) and endothelial progenitor cells (EPC) were stimulated in vitro with 3pRNA. Both cells types express RIG-I and react with receptor upregulation upon stimulation. Reactive oxygen species (ROS) formation is enhanced in both cell types, whereas apoptosis and proliferation is not significantly affected in HCAEC. Importantly, HCAEC release significant amounts of proinflammatory cytokines in response to RIG-I stimulation. Conclusion: This study shows that activation of the cytoplasmatic nucleic acid receptor RIG-I leads to endothelial dysfunction. RIG-I induced endothelial damage could therefore be an important pathway in atherogenesis.

Key role of the endothelial TGF-β/ALK1/endoglin signaling pathway in humans and rodents pulmonary hypertension.

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Benoît Gore

Full Text Available Mutations affecting transforming growth factor-beta (TGF-β superfamily receptors, activin receptor-like kinase (ALK-1, and endoglin (ENG occur in patients with pulmonary arterial hypertension (PAH. To determine whether the TGF-β/ALK1/ENG pathway was involved in PAH, we investigated pulmonary TGF-β, ALK1, ALK5, and ENG expressions in human lung tissue and cultured pulmonary-artery smooth-muscle-cells (PA-SMCs and pulmonary endothelial cells (PECs from 14 patients with idiopathic PAH (iPAH and 15 controls. Seeing that ENG was highly expressed in PEC, we assessed the effects of TGF-β on Smad1/5/8 and Smad2/3 activation and on growth factor production by the cells. Finally, we studied the consequence of ENG deficiency on the chronic hypoxic-PH development by measuring right ventricular (RV systolic pressure (RVSP, RV hypertrophy, and pulmonary arteriolar remodeling in ENG-deficient (Eng+/- and wild-type (Eng+/+ mice. We also evaluated the pulmonary blood vessel density, macrophage infiltration, and cytokine expression in the lungs of the animals. Compared to controls, iPAH patients had higher serum and pulmonary TGF-β levels and increased ALK1 and ENG expressions in lung tissue, predominantly in PECs. Incubation of the cells with TGF-β led to Smad1/5/8 phosphorylation and to a production of FGF2, PDGFb and endothelin-inducing PA-SMC growth. Endoglin deficiency protected mice from hypoxic PH. As compared to wild-type, Eng+/- mice had a lower pulmonary vessel density, and no change in macrophage infiltration after exposure to chronic hypoxia despite the higher pulmonary expressions of interleukin-6 and monocyte chemoattractant protein-1. The TGF-β/ALK1/ENG signaling pathway plays a key role in iPAH and experimental hypoxic PH via a direct effect on PECs leading to production of growth factors and inflammatory cytokines involved in the pathogenesis of PAH.

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

Science.gov (United States)

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.

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.

Bilirubin Prevents Atherosclerotic Lesion Formation in Low-Density Lipoprotein Receptor-Deficient Mice by Inhibiting Endothelial VCAM-1 and ICAM-1 Signaling.

Science.gov (United States)

Vogel, Megan E; Idelman, Gila; Konaniah, Eddy S; Zucker, Stephen D

2017-04-01

Numerous epidemiological studies support an inverse association between serum bilirubin levels and the incidence of cardiovascular disease; however, the mechanism(s) by which bilirubin may protect against atherosclerosis is undefined. The goals of the present investigations were to assess the ability of bilirubin to prevent atherosclerotic plaque formation in low-density lipoprotein receptor-deficient ( Ldlr -/- ) mice and elucidate the molecular processes underlying this effect. Bilirubin, at physiological concentrations (≤20 μmol/L), dose-dependently inhibits THP-1 monocyte migration across tumor necrosis factor α-activated human umbilical vein endothelial cell monolayers without altering leukocyte binding or cytokine production. A potent antioxidant, bilirubin effectively blocks the generation of cellular reactive oxygen species induced by the cross-linking of endothelial vascular cell adhesion molecule 1 (VCAM-1) or intercellular adhesion molecule 1 (ICAM-1). These findings were validated by treating cells with blocking antibodies or with specific inhibitors of VCAM-1 and ICAM-1 signaling. When administered to Ldlr -/- mice on a Western diet, bilirubin (30 mg/kg intraperitoneally) prevents atherosclerotic plaque formation, but does not alter circulating cholesterol or chemokine levels. Aortic roots from bilirubin-treated animals exhibit reduced lipid and collagen deposition, decreased infiltration of monocytes and lymphocytes, fewer smooth muscle cells, and diminished levels of chlorotyrosine and nitrotyrosine, without changes in VCAM-1 or ICAM-1 expression. Bilirubin suppresses atherosclerotic plaque formation in Ldlr -/- mice by disrupting endothelial VCAM-1- and ICAM-1-mediated leukocyte migration through the scavenging of reactive oxygen species signaling intermediaries. These findings suggest a potential mechanism for the apparent cardioprotective effects of bilirubin. © 2017 The Authors. Published on behalf of the American Heart Association, Inc

Monocytes/Macrophages Control Resolution of Transient Inflammatory Pain

Science.gov (United States)

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

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.

Endothelial RIG-I activation impairs endothelial function

Energy Technology Data Exchange (ETDEWEB)

Asdonk, Tobias, E-mail: tobias.asdonk@ukb.uni-bonn.de [Department of Medicine/Cardiology, University of Bonn, Sigmund-Freud-Str. 25, 53105 Bonn (Germany); Motz, Inga; Werner, Nikos [Department of Medicine/Cardiology, University of Bonn, Sigmund-Freud-Str. 25, 53105 Bonn (Germany); Coch, Christoph; Barchet, Winfried; Hartmann, Gunther [Institute for Clinical Chemistry and Clinical Pharmacology, University of Bonn, Sigmund-Freud-Str. 25, 53105 Bonn (Germany); Nickenig, Georg; Zimmer, Sebastian [Department of Medicine/Cardiology, University of Bonn, Sigmund-Freud-Str. 25, 53105 Bonn (Germany)

2012-03-30

Highlights: Black-Right-Pointing-Pointer RIG-I activation impairs endothelial function in vivo. Black-Right-Pointing-Pointer RIG-I activation alters HCAEC biology in vitro. Black-Right-Pointing-Pointer EPC function is affected by RIG-I stimulation in vitro. -- Abstract: Background: Endothelial dysfunction is a crucial part of the chronic inflammatory atherosclerotic process and is mediated by innate and acquired immune mechanisms. Recent studies suggest that pattern recognition receptors (PRR) specialized in immunorecognition of nucleic acids may play an important role in endothelial biology in a proatherogenic manner. Here, we analyzed the impact of endothelial retinoic acid inducible gene I (RIG-I) activation upon vascular endothelial biology. Methods and results: Wild type mice were injected intravenously with 32.5 {mu}g of the RIG-ligand 3pRNA (RNA with triphosphate at the 5 Prime end) or polyA control every other day for 7 days. In 3pRNA-treated mice, endothelium-depended vasodilation was significantly impaired, vascular oxidative stress significantly increased and circulating endothelial microparticle (EMP) numbers significantly elevated compared to controls. To gain further insight in RIG-I dependent endothelial biology, cultured human coronary endothelial cells (HCAEC) and endothelial progenitor cells (EPC) were stimulated in vitro with 3pRNA. Both cells types express RIG-I and react with receptor upregulation upon stimulation. Reactive oxygen species (ROS) formation is enhanced in both cell types, whereas apoptosis and proliferation is not significantly affected in HCAEC. Importantly, HCAEC release significant amounts of proinflammatory cytokines in response to RIG-I stimulation. Conclusion: This study shows that activation of the cytoplasmatic nucleic acid receptor RIG-I leads to endothelial dysfunction. RIG-I induced endothelial damage could therefore be an important pathway in atherogenesis.

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.

Effects of 17β-estradiol on the release of monocyte chemotactic protein-1 and MAPK activity in monocytes stimulated with peritoneal fluid from endometriosis patients.

Science.gov (United States)

Lee, Dong-Hyung; Kim, Seung-Chul; Joo, Jong-Kil; Kim, Hwi-Gon; Na, Young-Jin; Kwak, Jong-Young; Lee, Kyu-Sup

2012-03-01

Hormones and inflammation have been implicated in the pathological process of endometriosis; therefore, we investigated the combined effects of 17β-estradiol (E2) and peritoneal fluid obtained from patients with endometriosis (ePF) or a control peritoneal fluid (cPF) obtained from patients without endometriosis on the release of monocyte chemotactic protein-1 (MCP-1) by monocytes and the role of signaling pathways. Monocytes were cultured with ePF and cPF in the presence of E2; the MCP-1 levels in the supernatants were then measured by ELISA. In addition, mitogen activated protein kinase (MAPK) activation was measured by Western blotting of phosphorylated proteins. E2 down-regulated MCP-1 release by lipopolysaccharide- or cPF-treated monocytes, but failed to suppress its release by ePF-treated monocytes. The release of MCP-1 by ePF- and cPF-treated monocytes was efficiently abrogated by p38 mitogen activated protein kinase (MAPK) inhibitors; however, the MCP-1 release by cPF-treated monocytes, but not by ePF-treated monocytes, was blocked by a MAPK kinase inhibitor. In addition, ePF and cPF induced the phosphorylation of extracellular stress regulated kinase (ERK)1/2, p38 MAPK and c-Jun N-terminal kinase (JNK). E2 decreased the phosphorylation of p38 MAPK, but not ERK1/2 in ePF-treated monocytes; however, E2 decreased the phosphorylation of p38 MAPK, ERK1/2 and JNK in cPF-treated monocytes. The ability of E2 to modulate MCP-1 production is impaired in ePF-treated monocytes, which may be related to regulation of MAPK activity. These findings suggest that the failure of E2 to suppress ePF-treated production of MCP-1 may be involved in the pathogenesis of endometriosis. © 2012 The Authors. Journal of Obstetrics and Gynaecology Research © 2012 Japan Society of Obstetrics and Gynecology.

N-caffeoyltryptomine, a potent anti-inflammatory phenolic amide, suppressed MCP-1 expression in LPS-stimulated THP-1 cells and rats fed with a high fat diet

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Monocyte chemoattractant protein-1 (MCP-1) is a well-known chemokine critically involved in the pathophysiological progression of cardiovascular diseases such as arthrosclerosis. N-caffeoyltryptamine is a phenolic amide with strong anti-inflammatory effects. Therefore, in this paper, the potential e...

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

International Nuclear Information System (INIS)

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)

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

Science.gov (United States)

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.

Lactic acid delays the inflammatory response of human monocytes

Energy Technology Data Exchange (ETDEWEB)

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

Osteopontin Prevents Monocyte Recirculation and Apoptosis

OpenAIRE

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...

Significant sE-Selectin levels reduction after 6 months of anti-TNF-α therapy in non-diabetic patients with moderate-to-severe psoriasis.

Science.gov (United States)

Genre, Fernanda; Armesto, Susana; Corrales, Alfonso; López-Mejías, Raquel; Remuzgo-Martínez, Sara; Pina, Trinitario; Ubilla, Begoña; Mijares, Verónica; Martín-Varillas, José Luis; Rueda-Gotor, Javier; Portilla, Virginia; Dierssen-Sotos, Trinidad; González-López, Marcos Antonio; González-Vela, María Del Carmen; Blanco, Ricardo; Llorca, Javier; Hernández, José Luis; González-Gay, Miguel Ángel

2017-12-01

Psoriasis patients have high risk of atherosclerosis, characterized by endothelial dysfunction. We aimed to study the association of the endothelial activation biomarkers monocyte chemoattractant protein 1 (MCP-1), soluble (s) E-selectin and P-selectin with disease activity and severity in psoriasis patients treated with anti-TNF-α therapy. Also, to evaluate the relationship of metabolic syndrome features with these biomarkers and the effect of anti-TNF-α therapy on these molecules. Twenty-nine consecutive non-diabetic patients with moderate-to-severe psoriasis who underwent 6 months of anti-TNF-α-adalimumab therapy were studied. Metabolic and clinical evaluation was performed prior to anti-TNF-α treatment (time 0) and 6 months later. MCP-1, sE-selectin and sP-selectin serum levels were determined by ELISA. Dyslipidemic and obese patients showed higher MCP-1 levels at month 6 from the onset of anti-TNF-α therapy (p = .05 and .01, respectively). sE-selectin positively correlated with pro-inflammatory molecules such as asymmetric dimethylarginine, sP-selectin and resistin at baseline and month 6 (p psoriasis. Adalimumab therapy led to a reduction in sE-selectin levels, supporting the beneficial effect of anti-TNF-α therapy on mechanisms associated with the development of atherosclerosis in psoriasis.

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.

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.

Maturation and demise of human primary monocytes by carbon nanotubes

Science.gov (United States)

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

Energy Technology Data Exchange (ETDEWEB)

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.

Down-regulation of histamine-induced endothelial cell activation as potential anti-atherosclerotic activity of peptides from Spirulina maxima.

Science.gov (United States)

Vo, Thanh-Sang; Kim, Se-Kwon

2013-10-09

Histamine, a potent inflammatory mediator, has been known to cause the pathogenesis of atherosclerosis. In this sense, two bioactive peptides P1 (LDAVNR; 686Da) and P2 (MMLDF; 655Da) purified from gastric enzymatic hydrolysate of Spirulina maxima were examined for their protective effects against early atherosclerotic responses induced by histamine in EA.hy926 endothelial cells. Interestingly, both P1 and P2 exhibited inhibitory activities on the production and expression of IL-6 and MCP-1. Furthermore, P1 and P2 inhibited the production of adhesion molecules including P-selectin and E-selectin, and thus reducing in vitro cell adhesion of monocyte onto endothelial cells. In addition, the production of intracellular reactive oxygen species was observed to reduce in the presence of P1 or P2. Notably, the inhibitory activities of P1 and P2 were found due to down-regulating Egr-1 expression via histamine receptor and PKCδ-dependent MAPKs activation pathway. These results suggest that peptides P1 and P2 from S. maxima are effective to suppress histamine-induced endothelial cell activation that may contribute to the prevention of early atherosclerosis. Copyright © 2013 Elsevier B.V. All rights reserved.

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.

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

Science.gov (United States)

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.

The Role of miR-330-3p/PKC-α Signaling Pathway in Low-Dose Endothelial-Monocyte Activating Polypeptide-II Increasing the Permeability of Blood-Tumor Barrier

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Jiahui Liu

2017-12-01

Full Text Available This study was performed to determine whether EMAP II increases the permeability of the blood-tumor barrier (BTB by affecting the expression of miR-330-3p as well as its possible mechanisms. We determined the over-expression of miR-330-3p in glioma microvascular endothelial cells (GECs by Real-time PCR. Endothelial monocyte-activating polypeptide-II (EMAP-II significantly decreased the expression of miR-330-3p in GECs. Pre-miR-330-3p markedly decreased the permeability of BTB and increased the expression of tight junction (TJ related proteins ZO-1, occludin and claudin-5, however, anti-miR-330-3p had the opposite effects. Anti-miR-330-3p could enhance the effect of EMAP-II on increasing the permeability of BTB, however, pre-miR-330-3p partly reversed the effect of EMAP-II on that. Similarly, anti-miR-330-3p improved the effects of EMAP-II on increasing the expression levels of PKC-α and p-PKC-α in GECs and pre-miR-330-3p partly reversed the effects. MiR-330-3p could target bind to the 3′UTR of PKC-α. The results of in vivo experiments were similar to those of in vitro experiments. These suggested that EMAP-II could increase the permeability of BTB through inhibiting miR-330-3p which target negative regulation of PKC-α. Pre-miR-330-3p and PKC-α inhibitor decreased the BTB permeability and up-regulated the expression levels of ZO-1, occludin and claudin-5 while anti-miR-330-3p and PKC-α activator brought the reverse effects. Compared with EMAP-II, anti-miR-330-3p and PKC-α activator alone, the combination of the three combinations significantly increased the BTB permeability. EMAP-II combined with anti-miR-330-3p and PKCα activator could enhance the DOX’s effects on inhibiting the cell viabilities and increasing the apoptosis of U87 glioma cells. Our studies suggest that low-dose EMAP-II up-regulates the expression of PKC-α and increases the activity of PKC-α by inhibiting the expression of miR-330-3p, reduces the expression of ZO-1

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.

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

Gomesin acts in the immune system and promotes myeloid differentiation and monocyte/macrophage activation in mouse.

Science.gov (United States)

Buri, Marcus V; Dias, Carol C; Barbosa, Christiano M V; Nogueira-Pedro, Amanda; Ribeiro-Filho, Antonio C; Miranda, Antonio; Paredes-Gamero, Edgar J

2016-11-01

Due to the cytotoxic effect of antimicrobial peptides (AMP) against several microorganism and tumor cells has been proposed their association with the immune system. However, just a few reports have shown this relationship. In this study, mice were treated with gomesin, a β-hairpin AMP that exhibit high cytotoxicity against bacterial and tumor cells. Different effects in the immune system were observed, such as, decrease of CD3 + in T lymphocytes (Control: 17.7±1.4%; Gomesin: 7.67±1.2%) and in hematopoietic progenitors and increase of hematopoietic stem cell (Control: 0.046±0.004%; Gomesin: 0.067±0.003%), B220 + B lymphocytes (Control: 38.63±1.5%; Gomesin: 47.83±0.48%), and Mac-1 + F4/80 + macrophages (Control: 11.76±3.4%; Gomesin: 27.13±4.0%). Additionally, macrophage increase was accompanied by an increase of macrophage phagocytosis (Control 20.85±1.53; Gomesin 31.32±1 Geometric mean), interleukin 6 (Control: 47.24±1.9ng/mL; Gomesin: 138.68±33.68ng/mL) and monocyte chemoattractant protein-1 (Control: 0.872±0.093ng/mL; Gomesin: 1.83±0.067ng/mL). Thus, this report showed immunomodulatory activity of gomesin in the immune system of mice. Copyright © 2016 Elsevier Inc. All rights reserved.

Increasing cerebrospinal fluid chemokine concentrations despite undetectable cerebrospinal fluid HIV RNA in HIV-1-infected patients receiving antiretroviral therapy

NARCIS (Netherlands)

Gisolf, E. H.; van Praag, R. M.; Jurriaans, S.; Portegies, P.; Goudsmit, J.; Danner, S. A.; Lange, J. M.; Prins, J. M.

2000-01-01

Only limited data on cerebrospinal fluid (CSF) HIV-1 RNA responses and markers of local inflammation in CSF during antiretroviral therapy are available. HIV-RNA, soluble tumor necrosis factor (TNF)-receptor (sTNFr)-II, monocyte chemoattractant protein (MCP)-1, and interferon-gamma-inducible protein

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.

Kruppel-like factor 2 (KLF2) regulates proinflammatory activation of monocytes

Science.gov (United States)

Das, Hiranmoy; Kumar, Ajay; Lin, Zhiyong; Patino, Willmar D.; Hwang, Paul M.; Feinberg, Mark W.; Majumder, Pradip K.; Jain, Mukesh K.

2006-01-01

The mechanisms regulating activation of monocytes remain incompletely understood. Herein we provide evidence that Kruppel-like factor 2 (KLF2) inhibits proinflammatory activation of monocytes. In vitro, KLF2 expression in monocytes is reduced by cytokine activation or differentiation. Consistent with this observation, KLF2 expression in circulating monocytes is reduced in patients with chronic inflammatory conditions such as coronary artery disease. Adenoviral overexpression of KLF2 inhibits the LPS-mediated induction of proinflammatory factors, cytokines, and chemokines and reduces phagocytosis. Conversely, short interfering RNA-mediated reduction in KLF2 increased inflammatory gene expression. Reconstitution of immunodeficient mice with KLF2-overexpressing monocytes significantly reduced carrageenan-induced acute paw edema formation. Mechanistically, KLF2 inhibits the transcriptional activity of both NF-κB and activator protein 1, in part by means of recruitment of transcriptional coactivator p300/CBP-associated factor. These observations identify KLF2 as a novel negative regulator of monocytic activation. PMID:16617118

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.

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

Monocyte Trafficking, Engraftment, and Delivery of Nanoparticles and an Exogenous Gene into the Acutely Inflamed Brain Tissue - Evaluations on Monocyte-Based Delivery System for the Central Nervous System.

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Hsin-I Tong

Full Text Available The ability of monocytes and monocyte-derived macrophages (MDM to travel towards chemotactic gradient, traverse tissue barriers, and accumulate precisely at diseased sites makes them attractive candidates as drug carriers and therapeutic gene delivery vehicles targeting the brain, where treatments are often hampered by the blockade of the blood brain barrier (BBB. This study was designed to fully establish an optimized cell-based delivery system using monocytes and MDM, by evaluating their homing efficiency, engraftment potential, as well as carriage and delivery ability to transport nano-scaled particles and exogenous genes into the brain, following the non-invasive intravenous (IV cell adoptive transfer in an acute neuroinflammation mouse model induced by intracranial injection of Escherichia coli lipopolysaccharides. We demonstrated that freshly isolated monocytes had superior inflamed-brain homing ability over MDM cultured in the presence of macrophage colony stimulating factor. In addition, brain trafficking of IV infused monocytes was positively correlated with the number of adoptive transferred cells, and could be further enhanced by transient disruption of the BBB with IV administration of Mannitol, Bradykinin or Serotonin right before cell infusion. A small portion of transmigrated cells was detected to differentiate into IBA-1 positive cells with microglia morphology in the brain. Finally, with the use of superparamagnetic iron oxide nanoparticles SHP30, the ability of nanoscale agent-carriage monocytes to enter the inflamed brain region was validated. In addition, lentiviral vector DHIV-101 was used to introduce green fluorescent protein (GFP gene into monocytes, and the exogenous GFP gene was detected in the brain at 48 hours following IV infusion of the transduced monocytes. All together, our study has set up the optimized conditions for the more-in-depth tests and development of monocyte-mediated delivery, and our data supported

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

Systemic MCP1/CCR2 blockade and leukocyte specific MCP1/CCR2 inhibition affect aortic aneurysm formation differently

NARCIS (Netherlands)

de Waard, Vivian; Bot, Ilze; de Jager, Saskia C. A.; Talib, Sara; Egashira, Kensuke; de Vries, Margreet R.; Quax, Paul H. A.; Biessen, Erik A. L.; van Berkel, Theo J. C.

2010-01-01

Objective: CCR2, the receptor for monocyte chemoattractant protein 1 (MCP1), is involved in atherosclerosis and abdominal aortic aneurysms (AAAs). Here, we explored the potential beneficial blockade of the MCP1/CCR2 pathway. Methods: We applied an AAA model in aging apolipoprotein E deficient mice

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.

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

Green fluorescent protein (GFP color reporter gene visualizes parvovirus B19 non-structural segment 1 (NS1 transfected endothelial modification.

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Thomas Wurster

Full Text Available BACKGROUND: Human Parvovirus B19 (PVB19 has been associated with myocarditis putative due to endothelial infection. Whether PVB19 infects endothelial cells and causes a modification of endothelial function and inflammation and, thus, disturbance of microcirculation has not been elucidated and could not be visualized so far. METHODS AND FINDINGS: To examine the PVB19-induced endothelial modification, we used green fluorescent protein (GFP color reporter gene in the non-structural segment 1 (NS1 of PVB19. NS1-GFP-PVB19 or GFP plasmid as control were transfected in an endothelial-like cell line (ECV304. The endothelial surface expression of intercellular-adhesion molecule-1 (CD54/ICAM-1 and extracellular matrix metalloproteinase inducer (EMMPRIN/CD147 were evaluated by flow cytometry after NS-1-GFP or control-GFP transfection. To evaluate platelet adhesion on NS-1 transfected ECs, we performed a dynamic adhesion assay (flow chamber. NS-1 transfection causes endothelial activation and enhanced expression of ICAM-1 (CD54: mean ± standard deviation: NS1-GFP vs. control-GFP: 85.3 ± 11.2 vs. 61.6 ± 8.1; P<0.05 and induces endothelial expression of EMMPRIN/CD147 (CD147: mean ± SEM: NS1-GFP vs. control-GFP: 114 ± 15.3 vs. 80 ± 0.91; P<0.05 compared to control-GFP transfected cells. Dynamic adhesion assays showed that adhesion of platelets is significantly enhanced on NS1 transfected ECs when compared to control-GFP (P<0.05. The transfection of ECs was verified simultaneously through flow cytometry, immunofluorescence microscopy and polymerase chain reaction (PCR analysis. CONCLUSIONS: GFP color reporter gene shows transfection of ECs and may help to visualize NS1-PVB19 induced endothelial activation and platelet adhesion as well as an enhanced monocyte adhesion directly, providing in vitro evidence of possible microcirculatory dysfunction in PVB19-induced myocarditis and, thus, myocardial tissue damage.

Treatment of radiation exposure and regeneration medicine. Regeneration treatment of blood vessels by transplantation of autologous marrow monocytes

International Nuclear Information System (INIS)

Nagai, Kazuhiro; Kamihira, Shimeru; Matsumaru, Ichiro; Fukushima, Takuya; Yamaguchi, Hakuichiro; Miyazaki, Yasushi; Yamachika, Shiro; Eishi, Kiyoyuki; Tomonaga, Masao

2007-01-01

Described are usefulness and future view of regenerative medicine in the treatment of radiation exposure as exemplified by the vascular regeneration by autologous marrow cell transplantation. Vascular endothelial cells (VEC), possessing a high ability to divide, are known sensitive to radiation, which gives damage of blood vessel to alter its permeability leading to apoptosis of VEC, organ/tissue injuries and final damages in the cerebral blood vessels, central nervous system and skin, the acute radiation syndrome (ARS). Authors present successful cases of patients with chronic limb ischemia in the Therapeutic Angiogenesis using Cell Transplantation Trial (TACT), to whom the treatment is conducted with transplantation of autologous marrow monocyte fraction containing endothelial progenitor cells that differentiate to VEC. As well, they touch on a case of the patient encountered in a nuclear accident, mentioning that VEC are found partly derived from the donor after heamatopoietic stem cell transplantation (HSCT). Efficacy of HSCT in a literature is reviewed and commented to be an only limited one in 31 patients of various radiation accidents. However, treatment of ARS where stem cells are target, with regenerative medicine will become more useful in future, as basic and clinical researches will provide requisite findings. (T.I.)

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.

STAT3 activation in monocytes accelerates liver cancer progression

International Nuclear Information System (INIS)

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

Anthocyanin-Rich Extract from Red Chinese Cabbage Alleviates Vascular Inflammation in Endothelial Cells and Apo E−/− Mice

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Hee Kyoung Joo

2018-03-01

Full Text Available Anthocyanins, the most prevalent flavonoids in red/purple fruits and vegetables, are known to improve immune responses and reduce chronic disease risks. In this study, the anti-inflammatory activities of an anthocyanin-rich extract from red Chinese cabbage (ArCC were shown based on its inhibitory effects in cultured endothelial cells and hyperlipidemic apolipoprotein E-deficient mice. ArCC treatment suppressed monocyte adhesion to tumor necrosis factor-α-stimulated endothelial cells. This was validated by ArCC’s ability to downregulate the expression and transcription of endothelial adhesion molecules, determined by immunoblot and luciferase promoter assays, respectively. The regulation of adhesion molecules was accompanied by transcriptional inhibition of nuclear factor-κB, which restricted cytoplasmic localization as shown by immunocytochemistry. Administration of ArCC (150 or 300 mg/kg/day inhibited aortic inflammation in hyperlipidemic apolipoprotein E-deficient mice, as shown by in vivo imaging. Immunohistochemistry and plasma analysis showed that the aortas from these mice exhibited markedly lower leukocyte infiltration, reduced plaque formation, and lower concentrations of blood inflammatory cytokines than those observed in the control mice. The results suggest that the consumption of anthocyanin-rich red Chinese cabbage is closely correlated with lowering the risk of vascular inflammatory diseases.

Effects of TNF-alpha on Endothelial Cell Collective Migration

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Chen, Desu; Wu, Di; Helim Aranda-Espinoza, Jose; Losert, Wolfgang

2013-03-01

Tumor necrosis factor (TNF-alpha) is a small cell-signaling protein usually released by monocytes and macrophages during an inflammatory response. Previous work had shown the effects of TNF-alpha on single cell morphology, migration, and biomechanical properties. However, the effect on collective migrations remains unexplored. In this work, we have created scratches on monolayers of human umbilical endothelial cells (HUVECs) treated with 25ng/mL TNF-alpha on glass substrates. The wound healing like processes were imaged with phase contrast microscopy. Quantitative analysis of the collective migration of cells treated with TNF-alpha indicates that these cells maintain their persistent motion and alignment better than untreated cells. In addition, the collective migration was characterized by measuring the amount of non-affine deformations of the wound healing monolayer. We found a lower mean non-affinity and narrower distribution of non-affinities upon TNF-alpha stimulation. These results suggest that TNF-alpha introduces a higher degree of organized cell collective migration.

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.

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

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

Different effects of anthocyanins and phenolic acids from wild blueberry (Vaccinium angustifolium) on monocytes adhesion to endothelial cells in a TNF-α stimulated proinflammatory environment

DEFF Research Database (Denmark)

Del Bo', Cristian; Roursgaard, Martin; Porrini, Marisa

2016-01-01

Scope: Monocyte adhesion to the vascular endothelium is a crucial step in the early stagesof atherogenesis. This study aims to investigate the capacity of an anthocyanin (ACN) andphenolic acid (PA) rich fraction (RF) of a wild blueberry, single ACNs (cyanidin, malvidin,delphinidin) and related me...

Live Brugia malayi microfilariae inhibit transendothelial migration of neutrophils and monocytes.

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Jan-Hendrik Schroeder

Full Text Available Lymphatic filariasis is a major tropical disease caused by the parasite Brugia malayi. Microfilariae (Mf circulate in the peripheral blood for 2-3 hours in synchronisation with maximal feeding of the mosquito vector. When absent from the peripheral blood, Mf sequester in the capillaries of the lungs. Mf are therefore in close contact with vascular endothelial cells (EC and may induce EC immune function and/or wound repair mechanisms such as angiogenesis. In this study, Mf were co-cultured with human umbilical vein EC (HUVEC or human lung microvascular EC (HLMVEC and the transendothelial migration of leukocyte subsets was analysed. In addition, the protein and/or mRNA expression of chemokine, cytokine and angiogenic mediators in endothelial cells in the presence of live microfilariae were measured by a combination of cDNA arrays, protein arrays, ELISA and fluorescence antibody tests.Surprisingly, our findings indicate that Mf presence partially blocked transendothelial migration of monocytes and neutrophils, but not lymphocytes. However, Mf exposure did not result in altered vascular EC expression of key mediators of the tethering stage of extravasation, such as ICAM-1, VCAM-1 and various chemokines. To further analyse the immunological function of vascular EC in the presence of Mf, we measured the mRNA and/or protein expression of a number of pro-inflammatory mediators. We found that expression levels of the mediators tested were predominantly unaltered upon B. malayi Mf exposure. In addition, a comparison of angiogenic mediators induced by intact Mf and Wolbachia-depleted Mf revealed that even intact Mf induce the expression of remarkably few angiogenic mediators in vascular EC. Our study suggests that live microfilariae are remarkably inert in their induction and/or activation of vascular cells in their immediate local environment. Overall, this work presents important insights into the immunological function of the vascular endothelium during

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.

Study of some biochemical and genetic risk factors for ...

African Journals Online (AJOL)

The aim of this study was to evaluate the relation between asymmetric dimethylarginine (ADMA ), high sensitive C-reactive protein (hs-CRP), monocyte chemoattractant protein-1 (MCP-1) ( both serum levels and the genotypes of the MCP-1 A-2518G polymorphism) with the development of carotid atherosclerosis in systemic ...

Blow-up for a three dimensional Keller-Segel model with consumption of chemoattractant

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Jiang, Jie; Wu, Hao; Zheng, Songmu

2018-04-01

We investigate blow-up properties for the initial-boundary value problem of a Keller-Segel model with consumption of chemoattractant when the spatial dimension is three. Through a kinetic reformulation of the Keller-Segel system, we first derive some higher-order estimates and obtain certain blow-up criteria for the local classical solutions. These blow-up criteria generalize the results in [4,5] from the whole space R3 to the case of bounded smooth domain Ω ⊂R3. Lower global blow-up estimate on ‖ n ‖ L∞ (Ω) is also obtained based on our higher-order estimates. Moreover, we prove local non-degeneracy for blow-up points.

Blood monocyte oxidative burst activity in acute P. falciparum malaria

DEFF Research Database (Denmark)

Nielsen, H; Theander, T G

1989-01-01

The release of superoxide anion from blood monocytes was studied in eight patients with acute primary attack P. falciparum malaria. Before treatment a significant enhancement of the oxidative burst prevailed, which contrasts with previous findings of a depressed monocyte chemotactic responsiveness...

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

The impact of chromatin modification on the development of chronic complications in patients with diabetes

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Małgorzata Wegner

2015-08-01

Full Text Available Diabetes is a chronic, metabolic disease. Over 347 million people worldwide have diabetes. Chronic complications (retinopathy, nephropathy or neuropathy are the major dangerous outcome of this disease. Recent studies indicate a significant role of epigenetic regulation in the development of chronic complications in patients with diabetes. Hyperglycemia could cause abnormal regulation of the activity of enzymes participating in the post-translational histone modifications (PTHMs and initiation of changes in patterns of DNA methylation. It leads to modification of chromatin structure. These epigenetic abnormalities result in changes in the expression of genes involved in development of chronic inflammation, such as NF-KAPPAB (nuclear factor kappaB gene, TNFα (tumor necrosis factor a gene, IL6 (interleukin 6 gene or MCP1 (monocyte chemoattractant protein 1 gene. It enhances endothelial cell dysfunction, which plays an important role in development of chronic, diabetic complications. In addition, caused by hyperglycemia epigenetic modifications changes in structure of chromatin explains “metabolic memory”, a phenomenon of presence of pathological pathways related to the prolonged hyperglycemia in the past, despite maintaining good metabolic control later on.

Abscisic acid ameliorates atherosclerosis by suppressing macrophage and CD4+ T cell recruitment into the aortic wall.

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Guri, Amir J; Misyak, Sarah A; Hontecillas, Raquel; Hasty, Alyssa; Liu, Dongmin; Si, Hongwei; Bassaganya-Riera, Josep

2010-12-01

Abscisic acid (ABA) is a natural phytohormone which improves insulin sensitivity and reduces adipose tissue inflammation when supplemented into diets of obese mice. The objective of this study was to investigate the mechanisms by which ABA prevents or ameliorates atherosclerosis. apolipoprotein E-deficient (ApoE(-/-)) mice were fed high-fat diets with or without ABA for 84 days. Systolic blood pressure was assessed on Days 0, 28, 56 and 72. Gene expression, immune cell infiltration and histological lesions were evaluated in the aortic root wall. Human aortic endothelial cells were used to examine the effect of ABA on 3',5'-cyclic adenosine monophosphate (cAMP) and nitric oxide (NO) production in vitro. We report that ABA-treated mice had significantly improved systolic blood pressure and decreased accumulation of F4/80(+)CD11b(+) macrophages and CD4(+) T cells in aortic root walls. At the molecular level, ABA significantly enhanced aortic endothelial nitric oxide synthase (eNOS) and tended to suppress aortic vascular cell adhesion molecule-1 (VCAM-1) and monocyte chemoattractant protein-1 (MCP-1) expression and plasma MCP-1 concentrations. ABA also caused a dose-dependent increase in intracellular concentrations of cAMP and NO and up-regulated eNOS mRNA expression in human aortic endothelial cells. This is the first report showing that ABA prevents or ameliorates atherosclerosis-induced hypertension, immune cell recruitment into the aortic root wall and up-regulates aortic eNOS expression in ApoE(-/-) mice. Copyright © 2010 Elsevier Inc. All rights reserved.

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.

Exposure to ultrafine particles, intracellular production of reactive oxygen species in leukocytes and altered levels of endothelial progenitor cells

International Nuclear Information System (INIS)

Jantzen, Kim; Møller, Peter; Karottki, Dorina Gabriela; Olsen, Yulia; Bekö, Gabriel; Clausen, Geo; Hersoug, Lars-Georg; Loft, Steffen

2016-01-01

Exposure to particles in the fine and ultrafine size range has been linked to induction of low-grade systemic inflammation, oxidative stress and development of cardiovascular diseases. Declining levels of endothelial progenitor cells within systemic circulation have likewise been linked to progression of cardiovascular diseases. The objective was to determine if exposure to fine and ultrafine particles from indoor and outdoor sources, assessed by personal and residential indoor monitoring, is associated with altered levels of endothelial progenitor cells, and whether such effects are related to leukocyte-mediated oxidative stress. The study utilized a cross sectional design performed in 58 study participants from a larger cohort. Levels of circulating endothelial progenitor cells, defined as either late (CD34 + KDR + cells) or early (CD34 + CD133 + KDR + cells) subsets were measured using polychromatic flow cytometry. We additionally measured production of reactive oxygen species in leukocyte subsets (lymphocytes, monocytes and granulocytes) by flow cytometry using intracellular 2′,7′-dichlorofluoroscein. The measurements encompassed both basal levels of reactive oxygen species production and capacity for reactive oxygen species production for each leukocyte subset. We found that the late endothelial progenitor subset was negatively associated with levels of ultrafine particles measured within the participant residences and with reactive oxygen species production capacity in lymphocytes. Additionally, the early endothelial progenitor cell levels were positively associated with a personalised measure of ultrafine particle exposure and negatively associated with both basal and capacity for reactive oxygen species production in lymphocytes and granulocytes, respectively. Our results indicate that exposure to fine and ultrafine particles derived from indoor sources may have adverse effects on human vascular health.

Femtosecond laser cutting of endothelial grafts: comparison of endothelial and epithelial applanation.

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Bernard, Aurélien; He, Zhiguo; Gauthier, Anne Sophie; Trone, Marie Caroline; Baubeau, Emmanuel; Forest, Fabien; Dumollard, Jean Marc; Peocʼh, Michel; Thuret, Gilles; Gain, Philippe

2015-02-01

Stromal surface quality of endothelial lamellae cut for endothelial keratoplasty with a femtosecond laser (FSL) with epithelial applanation remains disappointing. Applanation of the endothelial side of the cornea, mounted inverted on an artificial chamber, has therefore been proposed to improve cut quality. We compared lamellar quality after FSL cutting using epithelial versus endothelial applanation. Lamellae were cut with an FSL from organ-cultured corneas. After randomization, 7 were cut with epithelial applanation and 7 with endothelial applanation. Lamellae of 50-, 75-, and 100-μm thickness were targeted. Thickness was measured by optical coherence tomography before and immediately after cutting. Viable endothelial cell density was quantified immediately after cutting using triple labeling with Hoechst/ethidium/calcein-AM coupled with image analysis with ImageJ. The stromal surface was evaluated by 9 masked observers using semiquantitative scoring of scanning electronic microscopy images. Histology of 2 samples was also analyzed before lamellar detachment. Precision (difference in target/actual thickness) and thickness regularity [coefficient of variation (CV) of 10 measurements] were significantly better with endothelial applanation (precision: 18 μm; range, 10-30; CV: 11%; range, 8-12) than with epithelial applanation (precision: 84 μm; range, 54-107; P = 0.002; CV: 24%; range, 13-47; P = 0.001). Endothelial applanation provided thinner lamellae. However, viable endothelial cell density was significantly lower after endothelial applanation (1183 cells/mm2; range, 787-1725 versus 1688 cells/mm2; range, 1288-2025; P = 0.018). FSL cutting of endothelial lamellae using endothelial applanation provides thinner more regular grafts with more predictable thickness than with conventional epithelial applanation but strongly reduces the pool of viable endothelial cells.

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

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

Tolerance of monocytes and macrophages in response to bacterial endotoxin

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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.

Inhibitory effect of trans-caryophyllene (TC) on leukocyte-endothelial attachment.

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Zhang, Zhen; Yang, Chunfeng; Dai, Xinlun; Ao, Yu; Li, Yumei

2017-08-15

trans-Caryophyllene (TC) is a major component found in the essential oils of many spices and foods/medicinal plants. It is a natural sesquiterpene and has been the subject of numerous studies. However, the effects of TC on vascular inflammation remain unknown. In this study, we reported that TC treatment in human umbilical vein endothelial cells (HUVECs) prevented attachment of monocytic leukemia cell line THP-1 cells to endothelial cells. In addition, in vivo results indicate that TC inhibited macrophage infiltration to the aortic surface and reduced total serum levels of cholesterol and triglycerides. Importantly, administration of TC could inhibit the induction of vascular cell adhesion molecule-1 (VCAM-1) both in vitro and in vivo. Notably, our data indicate that the inhibitory effects of TC on the expression of VCAM-1 are mediated by the JAK2/STAT1/IRF-1 pathway. TC is a specific agonist of the type 2 cannabinoid receptor (CB2R). Importantly, we further verified that the inhibitory effects of TC on the expression of IRF-1 and VCAM-1 are dependent on activation of CB2R. Inhibition of CB2R by either specific inhibitors or RNA interference abolished the inhibitory effects of TC on the expression of IRF-1 and VCAM-1. Our results suggest that TC might have a capacity to suppress the development of atherosclerosis. Copyright © 2017 Elsevier Inc. All rights reserved.

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.

Angiopoietin-2 regulates gene expression in TIE2-expressing monocytes and augments their inherent proangiogenic functions.

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Coffelt, Seth B; Tal, Andrea O; Scholz, Alexander; De Palma, Michele; Patel, Sunil; Urbich, Carmen; Biswas, Subhra K; Murdoch, Craig; Plate, Karl H; Reiss, Yvonne; Lewis, Claire E

2010-07-01

TIE2-expressing monocytes/macrophages (TEM) are a highly proangiogenic subset of myeloid cells in tumors. Here, we show that circulating human TEMs are already preprogrammed in the circulation to be more angiogenic and express higher levels of such proangiogenic genes as matrix metalloproteinase-9 (MMP-9), VEGFA, COX-2, and WNT5A than TIE2(-) monocytes. Additionally, angiopoietin-2 (ANG-2) markedly enhanced the proangiogenic activity of TEMs and increased their expression of two proangiogenic enzymes: thymidine phosphorylase (TP) and cathepsin B (CTSB). Three "alternatively activated" (or M2-like) macrophage markers were also upregulated by ANG-2 in TEMs: interleukin-10, mannose receptor (MRC1), and CCL17. To investigate the effects of ANG-2 on the phenotype and function of TEMs in tumors, we used a double-transgenic (DT) mouse model in which ANG-2 was specifically overexpressed by endothelial cells. Syngeneic tumors grown in these ANG-2 DT mice were more vascularized and contained greater numbers of TEMs than those in wild-type (WT) mice. In both tumor types, expression of MMP-9 and MRC1 was mainly restricted to tumor TEMs rather than TIE2(-) macrophages. Furthermore, tumor TEMs expressed higher levels of MRC1, TP, and CTSB in ANG-2 DT tumors than WT tumors. Taken together, our data show that although circulating TEMs are innately proangiogenic, exposure to tumor-derived ANG-2 stimulates these cells to exhibit a broader, tumor-promoting phenotype. As such, the ANG-2-TEM axis may represent a new target for antiangiogenic cancer therapies. Copyright 2010 AACR.

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

DEFF Research Database (Denmark)

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....

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

Endothelial mineralocorticoid receptor activation mediates endothelial dysfunction in diet-induced obesity.

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Schäfer, Nicola; Lohmann, Christine; Winnik, Stephan; van Tits, Lambertus J; Miranda, Melroy X; Vergopoulos, Athanasios; Ruschitzka, Frank; Nussberger, Jürg; Berger, Stefan; Lüscher, Thomas F; Verrey, François; Matter, Christian M

2013-12-01

Aldosterone plays a crucial role in cardiovascular disease. 'Systemic' inhibition of its mineralocorticoid receptor (MR) decreases atherosclerosis by reducing inflammation and oxidative stress. Obesity, an important cardiovascular risk factor, is an inflammatory disease associated with increased plasma aldosterone levels. We have investigated the role of the 'endothelial' MR in obesity-induced endothelial dysfunction, the earliest stage in atherogenesis. C57BL/6 mice were exposed to a normal chow diet (ND) or a high-fat diet (HFD) alone or in combination with the MR antagonist eplerenone (200 mg/kg/day) for 14 weeks. Diet-induced obesity impaired endothelium-dependent relaxation in response to acetylcholine, whereas eplerenone treatment of obese mice prevented this. Expression analyses in aortic endothelial cells isolated from these mice revealed that eplerenone attenuated expression of pro-oxidative NADPH oxidase (subunits p22phox, p40phox) and increased expression of antioxidative genes (glutathione peroxidase-1, superoxide dismutase-1 and -3) in obesity. Eplerenone did not affect obesity-induced upregulation of cyclooxygenase (COX)-1 or prostacyclin synthase. Endothelial-specific MR deletion prevented endothelial dysfunction in obese (exhibiting high 'endogenous' aldosterone) and in 'exogenous' aldosterone-infused lean mice. Pre-incubation of aortic rings from aldosterone-treated animals with the COX-inhibitor indomethacin restored endothelial function. Exogenous aldosterone administration induced endothelial expression of p22phox in the presence, but not in the absence of the endothelial MR. Obesity-induced endothelial dysfunction depends on the 'endothelial' MR and is mediated by an imbalance of oxidative stress-modulating mechanisms. Therefore, MR antagonists may represent an attractive therapeutic strategy in the increasing population of obese patients to decrease vascular dysfunction and subsequent atherosclerotic complications.

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

Stent revascularization restores cortical blood flow and reverses tissue hypoxia in atherosclerotic renal artery stenosis but fails to reverse inflammatory pathways or glomerular filtration rate.

Science.gov (United States)

Saad, Ahmed; Herrmann, Sandra M S; Crane, John; Glockner, James F; McKusick, Michael A; Misra, Sanjay; Eirin, Alfonso; Ebrahimi, Behzad; Lerman, Lilach O; Textor, Stephen C

2013-08-01

Atherosclerotic renal artery stenosis (ARAS) is known to reduce renal blood flow, glomerular filtration rate (GFR) and amplify kidney hypoxia, but the relationships between these factors and tubulointerstitial injury in the poststenotic kidney are poorly understood. The purpose of this study was to examine the effect of renal revascularization in ARAS on renal tissue hypoxia and renal injury. Inpatient studies were performed in patients with ARAS (n=17; >60% occlusion) before and 3 months after stent revascularization, or in patients with essential hypertension (n=32), during fixed Na(+) intake and angiotensin converting enzyme/angiotensin receptors blockers Rx. Single kidney cortical, medullary perfusion, and renal blood flow were measured using multidetector computed tomography, and GFR by iothalamate clearance. Tissue deoxyhemoglobin levels (R(2)*) were measured by blood oxygen level-dependent MRI at 3T, as was fractional kidney hypoxia (percentage of axial area with R(2)*>30/s). In addition, we measured renal vein levels of neutrophil gelatinase-associated lipocalin, monocyte chemoattractant protein-1, and tumor necrosis factor-α. Pre-stent single kidney renal blood flow, perfusion, and GFR were reduced in the poststenotic kidney. Renal vein neutrophil gelatinase-associated lipocalin, tumor necrosis factor-α, monocyte chemoattractant protein-1, and fractional hypoxia were higher in untreated ARAS than in essential hypertension. After stent revascularization, fractional hypoxia fell (Pblood flow, whereas GFR and neutrophil gelatinase-associated lipocalin, monocyte chemoattractant protein-1, and tumor necrosis factor-α remained unchanged. These data demonstrate that despite reversal of renal hypoxia and partial restoration of renal blood flow after revascularization, inflammatory cytokines and injury biomarkers remained elevated and GFR failed to recover in ARAS. Restoration of vessel patency alone failed to reverse tubulointerstitial damage and partly

Macrophage proinflammatory response to the titanium alloy equipment in dental implantation.

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Chen, X; Li, H S; Yin, Y; Feng, Y; Tan, X W

2015-08-07

Titanium alloy and stainless steel (SS) had been widely used as dental implant materials because of their affinity with epithelial tissue and connective tissue, and good physical, chemical, biological, mechanical properties and processability. We compared the effects of titanium alloy and SS on macrophage cytokine expression as well as their biocompatibility. Mouse macrophage RAW264.7 cells were cultured on titanium alloy and SS surfaces. Cells were counted by scanning electron microscopy. A nitride oxide kit was used to detect released nitric oxide by macrophages on the different materials. An enzyme linked immunosorbent assay was used to detect monocyte chemoattractant protein-1 levels. Scanning electron microscopy revealed fewer macrophages on the surface of titanium alloy (48.2 ± 6.4 x 10(3) cells/cm(2)) than on SS (135 ± 7.3 x 10(3) cells/cm(2)). The nitric oxide content stimulated by titanium alloy was 22.5 mM, which was lower than that stimulated by SS (26.8 mM), but the difference was not statistically significant (P = 0.07). The level of monocyte chemoattractant protein-1 released was significantly higher in the SS group (OD value = 0.128) than in the titanium alloy group (OD value = 0.081) (P = 0.024). The transforming growth factor-b1 mRNA expression levels in macrophages after stimulation by titanium alloy for 12 and 36 h were significantly higher than that after stimulation by SS (P = 0.31 and 0.25, respectively). Macrophages participate in the inflammatory response by regulating cytokines such as nitric oxide, monocyte chemoattractant protein-1, and transforming growth factor-b1. There were fewer macrophages and lower inflammation on the titanium alloy surface than on the SS surface. Titanium alloy materials exhibited better biological compatibility than did SS.

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.

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.

Recruitment of macrophages from the spleen contributes to myocardial fibrosis and hypertension induced by angiotensin II

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Ning-Ping Wang

2017-05-01

Full Text Available Introduction: The purpose of this study was to determine whether macrophages migrated from the spleen are associated with angiotensin II-induced cardiac fibrosis and hypertension. Methods: Sprague-Dawley rats were subjected to angiotensin II infusion in vehicle (500 ng/kg/min for up to four weeks. In splenectomy, the spleen was removed before angiotensin II infusion. In the angiotensin II AT1 receptor blockade, telmisartan was administered by gastric gavage (10 mg/kg/day during angiotensin II infusion. The heart and aorta were isolated for Western blot analysis and immunohistochemistry. Results: Angiotensin II infusion caused a significant reduction in the number of monocytes in the spleen through the AT1 receptor-activated monocyte chemoattractant protein-1. Comparison of angiotensin II infusion, splenectomy and telmisartan comparatively reduced the recruitment of macrophages into the heart. Associated with this change, transforming growth factor β1 expression and myofibroblast proliferation were inhibited, and Smad2/3 and collagen I/III were downregulated. Furthermore, interstitial/perivascular fibrosis was attenuated. These modifications occurred in coincidence with reduced blood pressure. At week 4, invasion of macrophages and myofibroblasts in the thoracic aorta was attenuated and expression of endothelial nitric oxide synthase was upregulated, along with a reduction in aortic fibrosis. Conclusions: These results suggest that macrophages when recruited into the heart and aorta from the spleen potentially contribute to angiotensin II-induced cardiac fibrosis and hypertension.

[The role of endothelial cells and endothelial precursor cells in angiogenesis].

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Poreba, Małgorzata; Usnarska-Zubkiewicz, Lidia; Kuliczkowski, Kazimierz

2006-01-01

Endothelium plays a key role in maintenance of vascular homeostasis in human organism. According to new data endothelial cells and hematopoietic cells have a common precursor in prenatal life--a hemangioblast, which explains the fact of sharing the same determinants on the surface of both type of cells. Circulating endothelial precursors were identified in adults and this suggests that hemangioblasts may be present not only during embriogenesis. In some clinical situations the increased numbers of endothelial cells and endothelial precursors were noted, and especially in patients with neoplastic diseases, which is probably the result of increased angiogenesis. Endothelial precursors are thought to be the promice for therapeutic purposes in future--to increase local angiogenesis.

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.

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.

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.

PI3-kinase γ promotes Rap1a-mediated activation of myeloid cell integrin α4β1, leading to tumor inflammation and growth.

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Michael C Schmid

Full Text Available Tumor inflammation, the recruitment of myeloid lineage cells into the tumor microenvironment, promotes angiogenesis, immunosuppression and metastasis. CD11b+Gr1lo monocytic lineage cells and CD11b+Gr1hi granulocytic lineage cells are recruited from the circulation by tumor-derived chemoattractants, which stimulate PI3-kinase γ (PI3Kγ-mediated integrin α4 activation and extravasation. We show here that PI3Kγ activates PLCγ, leading to RasGrp/CalDAG-GEF-I&II mediated, Rap1a-dependent activation of integrin α4β1, extravasation of monocytes and granulocytes, and inflammation-associated tumor progression. Genetic depletion of PLCγ, CalDAG-GEFI or II, Rap1a, or the Rap1 effector RIAM was sufficient to prevent integrin α4 activation by chemoattractants or activated PI3Kγ (p110γCAAX, while activated Rap (RapV12 promoted constitutive integrin activation and cell adhesion that could only be blocked by inhibition of RIAM or integrin α4β1. Similar to blockade of PI3Kγ or integrin α4β1, blockade of Rap1a suppressed both the recruitment of monocytes and granulocytes to tumors and tumor progression. These results demonstrate critical roles for a PI3Kγ-Rap1a-dependent pathway in integrin activation during tumor inflammation and suggest novel avenues for cancer therapy.

Cinnamaldehyde inhibits the tumor necrosis factor-α-induced expression of cell adhesion molecules in endothelial cells by suppressing NF-κB activation: Effects upon IκB and Nrf2

International Nuclear Information System (INIS)

Liao, B.-C.; Hsieh, C.-W.; Liu, Y.-C.; Tzeng, T.-T.; Sun, Y.-W.; Wung, B.-S.

2008-01-01

The production of adhesion molecules and subsequent attachment of leukocytes to endothelial cells (ECs) are critical early events in atherogenesis. These adhesion molecules thus play an important role in the development of this disease. Recent studies have highlighted the chemoprotective and anti-inflammatory effects of cinnamaldehyde, a Cinnamomum cassia Presl-specific diterpene. In our current study, we have examined the effects of both cinnamaldehyde and extracts of C. cassia on cytokine-induced monocyte/human endothelial cell interactions. We find that these compounds inhibit the adhesion of TNFα-induced monocytes to endothelial cells and suppress the expression of the cell adhesion molecules, VCAM-1 and ICAM-1, at the transcriptional level. Moreover, in TNFα-treated ECs, the principal downstream signal of VCAM-1 and ICAM-1, NF-κB, was also found to be abolished in a time-dependent manner. Interestingly, cinnamaldehyde exerts its anti-inflammatory effects by blocking the degradation of the inhibitory protein IκB-α, but only in short term pretreatments, whereas it does so via the induction of Nrf2-related genes, including heme-oxygenase-1 (HO-1), over long term pretreatments. Treating ECs with zinc protoporphyrin, a HO-1 inhibitor, partially blocks the anti-inflammatory effects of cinnamaldehyde. Elevated HO-1 protein levels were associated with the inhibition of TNFα-induced ICAM-1 expression. In addition to HO-1, we also found that cinnamaldehyde can upregulate Nrf2 in nuclear extracts, and can increase ARE-luciferase activity and upregulate thioredoxin reductase-1, another Nrf2-related gene. Moreover, cinnamaldehyde exposure rapidly reduces the cellular GSH levels in ECs over short term treatments but increases these levels after 9 h exposure. Hence, our present findings indicate that cinnamaldehyde suppresses TNF-induced singling pathways via two distinct mechanisms that are activated by different pretreatment periods

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.

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

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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

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.

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

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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

Anti-Inflammatory effect of Buddleja officinalis on vascular inflammation in human umbilical vein endothelial cells.

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Lee, Yun Jung; Moon, Mi Kyoung; Hwang, Sun Mi; Yoon, Jung Joo; Lee, So Min; Seo, Kwan Soo; Kim, Jin Sook; Kang, Dae Gill; Lee, Ho Sub

2010-01-01

Vascular inflammation process has been suggested to be an important risk factor in the initiation and development of atherosclerosis. In this study, we investigated whether and by what mechanisms an aqueous extract of Buddleja officinalis (ABO) inhibited the expressions of cellular adhesion molecules, which are relevant to inflammation and atherosclerosis. Pretreatment of human umbilical vein endothelial cells (HUVEC) with ABO (1-10 microg/ml) for 18 hours dose-dependently inhibited TNF-alpha-induced adhesion U937 monocytic cells, as well as mRNA and protein expressions of vascular cell adhesion molecule-1 (VCAM-1), and intercellular cell adhesion molecule-1 (ICAM-1). Pretreatment with ABO also blocked TNF-alpha-induced ROS formation. Nuclear factor-kappa B (NF-kappaB) is required in the transcription of these adhesion molecule genes. Western blot analysis revealed that ABO inhibits the translocation of the p65 subunit of NF-kappaB to the nucleus. ABO inhibited the TNF-alpha-induced degradation of IkappaB-alpha, an inhibitor of NF-kappaB, by inhibiting the phosphorylation of IkappaB-alpha in HUVEC. Taken together, ABO could reduce cytokine-induced endothelial adhesiveness throughout down-regulating intracellular ROS production, NF-kappaB, and adhesion molecule expression in HUVEC, suggesting that the natural herb Buddleja officinalis may have potential implications in atherosclerosis.

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.

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.

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.

Platelets as a Novel Source of Pro-Inflammatory Chemokine CXCL14

Directory of Open Access Journals (Sweden)

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

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.

Obesity-induced vascular inflammation involves elevated arginase activity.

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Yao, Lin; Bhatta, Anil; Xu, Zhimin; Chen, Jijun; Toque, Haroldo A; Chen, Yongjun; Xu, Yimin; Bagi, Zsolt; Lucas, Rudolf; Huo, Yuqing; Caldwell, Ruth B; Caldwell, R William

2017-11-01

Obesity-induced vascular dysfunction involves pathological remodeling of the visceral adipose tissue (VAT) and increased inflammation. Our previous studies showed that arginase 1 (A1) in endothelial cells (ECs) is critically involved in obesity-induced vascular dysfunction. We tested the hypothesis that EC-A1 activity also drives obesity-related VAT remodeling and inflammation. Our studies utilized wild-type and EC-A1 knockout (KO) mice made obese by high-fat/high-sucrose (HFHS) diet. HFHS diet induced increases in body weight, fasting blood glucose, and VAT expansion. This was accompanied by increased arginase activity and A1 expression in vascular ECs and increased expression of tumor necrosis factor-α (TNF-α), monocyte chemoattractant protein-1 (MCP-1), interleukin-10 (IL-10), vascular cell adhesion molecule-1 (VCAM-1), and intercellular adhesion molecule-1 (ICAM-1) mRNA and protein in both VAT and ECs. HFHS also markedly increased circulating inflammatory monocytes and VAT infiltration by inflammatory macrophages, while reducing reparative macrophages. Additionally, adipocyte size and fibrosis increased and capillary density decreased in VAT. These effects of HFHS, except for weight gain and hyperglycemia, were prevented or reduced in mice lacking EC-A1 or treated with the arginase inhibitor 2-( S )-amino-6-boronohexanoic acid (ABH). In mouse aortic ECs, exposure to high glucose (25 mM) and Na palmitate (200 μM) reduced nitric oxide production and increased A1, TNF-α, VCAM-1, ICAM-1, and MCP-1 mRNA, and monocyte adhesion. Knockout of EC-A1 or ABH prevented these effects. HFHS diet-induced VAT inflammation is mediated by EC-A1 expression/activity. Limiting arginase activity is a possible therapeutic means of controlling obesity-induced vascular and VAT inflammation.

Hypoxia, leukocytes, and the pulmonary circulation.

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Stenmark, Kurt R; Davie, Neil J; Reeves, John T; Frid, Maria G

2005-02-01

Data are rapidly accumulating in support of the idea that circulating monocytes and/or mononuclear fibrocytes are recruited to the pulmonary circulation of chronically hypoxic animals and that these cells play an important role in the pulmonary hypertensive process. Hypoxic induction of monocyte chemoattractant protein-1, stromal cell-derived factor-1, vascular endothelial growth factor-A, endothelin-1, and tumor growth factor-beta(1) in pulmonary vessel wall cells, either directly or indirectly via signals from hypoxic lung epithelial cells, may be a critical first step in the recruitment of circulating leukocytes to the pulmonary circulation. In addition, hypoxic stress appears to induce release of increased numbers of monocytic progenitor cells from the bone marrow, and these cells may have upregulated expression of receptors for the chemokines produced by the lung circulation, which thus facilitates their specific recruitment to the pulmonary site. Once present, macrophages/fibrocytes may exert paracrine effects on resident pulmonary vessel wall cells stimulating proliferation, phenotypic modulation, and migration of resident fibroblasts and smooth muscle cells. They may also contribute directly to the remodeling process through increased production of collagen and/or differentiation into myofibroblasts. In addition, they could play a critical role in initiating and/or supporting neovascularization of the pulmonary artery vasa vasorum. The expanded vasa network may then act as a conduit for further delivery of circulating mononuclear cells to the pulmonary arterial wall, creating a feedforward loop of pathological remodeling. Future studies will need to determine the mechanisms that selectively induce leukocyte/fibrocyte recruitment to the lung circulation under hypoxic conditions, their direct role in the remodeling process via production of extracellular matrix and/or differentiation into myofibroblasts, their impact on the phenotype of resident smooth muscle

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

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

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

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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.

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.

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.

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

Directory of Open Access Journals (Sweden)

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.

ER Alpha Rapid Signaling Is Required for Estrogen Induced Proliferation and Migration of Vascular Endothelial Cells.

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Qing Lu

Full Text Available Estrogen promotes the proliferation and migration of vascular endothelial cells (ECs, which likely underlies its ability to accelerate re-endothelialization and reduce adverse remodeling after vascular injury. In previous studies, we have shown that the protective effects of E2 (the active endogenous form of estrogen in vascular injury require the estrogen receptor alpha (ERα. ERα transduces the effects of estrogen via a classical DNA binding, "genomic" signaling pathway and via a more recently-described "rapid" signaling pathway that is mediated by a subset of ERα localized to the cell membrane. However, which of these pathways mediates the effects of estrogen on endothelial cells is poorly understood. Here we identify a triple point mutant version of ERα (KRR ERα that is specifically defective in rapid signaling, but is competent to regulate transcription through the "genomic" pathway. We find that in ECs expressing wild type ERα, E2 regulates many genes involved in cell migration and proliferation, promotes EC migration and proliferation, and also blocks the adhesion of monocytes to ECs. ECs expressing KRR mutant ERα, however, lack all of these responses. These observations establish KRR ERα as a novel tool that could greatly facilitate future studies into the vascular and non-vascular functions of ERα rapid signaling. Further, they support that rapid signaling through ERα is essential for many of the transcriptional and physiological responses of ECs to E2, and that ERα rapid signaling in ECs, in vivo, may be critical for the vasculoprotective and anti-inflammatory effects of estrogen.

γ-Oryzanol reduces adhesion molecule expression in vascular endothelial cells via suppression of nuclear factor-κB activation.

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Sakai, Satoshi; Murata, Takahisa; Tsubosaka, Yoshiki; Ushio, Hideki; Hori, Masatoshi; Ozaki, Hiroshi

2012-04-04

γ-Oryzanol (γ-ORZ) is a mixture of phytosteryl ferulates purified from rice bran oil. In this study, we examined whether γ-ORZ represents a suppressive effect on the lipopolysaccharide (LPS)-induced adhesion molecule expression on vascular endothelium. Treatment with LPS elevated the mRNA expression of vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1), and E-selectin in bovine aortic endothelial cells (BAECs). Pretreatment with γ-ORZ dose-dependently decreased the LPS-mediated expression of these genes. Western blotting also revealed that pretreatment with γ-ORZ dose-dependently inhibited LPS-induced VCAM-1 expression in human umbilical vein endothelial cells. Consistently, pretreatment with γ-ORZ dose-dependently reduced LPS-induced U937 monocyte adhesion to BAECs. In immunofluorescence, LPS caused nuclear factor-κB (NF-κB) nuclear translocation in 40% of BAECs, which indicates NF-κB activation. Pretreatment with γ-ORZ, as well as its components (cycloartenyl ferulate, ferulic acid, or cycloartenol), dose-dependently inhibited LPS-mediated NF-κB activation. Collectively, our results suggested that γ-ORZ reduced LPS-mediated adhesion molecule expression through NF-κB inhibition in vascular endothelium.

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...

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

NARCIS (Netherlands)

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

Early Diagnosis and Intervention Strategies for Post-Traumatic Heterotopic Ossification in Severely Injured Extremities

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2016-12-01

factor [GM-CSF], MCP- 1, MIP-1[ alpha ], RANTES, and tumor necrosis factor -[ alpha ]) were quantified using Beadlyte Human 22- Plex...regulated on activation, normal T cell expressed and secreted), tumor necrosis factor (TNF)-α, and monocyte chemoattractant protein (MCP)-1 were...NM_013174 Transforming growth factor , beta 3 Involved in embryogenesis and cell differentiation. Tnf NM_012675 Tumor necrosis factor

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

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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.

Myeloid-Epithelial-Reproductive Receptor Tyrosine Kinase and Milk Fat Globule Epidermal Growth Factor 8 Coordinately Improve Remodeling After Myocardial Infarction via Local Delivery of Vascular Endothelial Growth Factor.

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Howangyin, Kiave-Yune; Zlatanova, Ivana; Pinto, Cristina; Ngkelo, Anta; Cochain, Clément; Rouanet, Marie; Vilar, José; Lemitre, Mathilde; Stockmann, Christian; Fleischmann, Bernd K; Mallat, Ziad; Silvestre, Jean-Sébastien

2016-03-01

In infarcted heart, improper clearance of dying cells by activated neighboring phagocytes may precipitate the transition to heart failure. We analyzed the coordinated role of 2 major mediators of efferocytosis, the myeloid-epithelial-reproductive protein tyrosine kinase (Mertk) and the milk fat globule epidermal growth factor (Mfge8), in directing cardiac remodeling by skewing the inflammatory response after myocardial infarction. We generated double-deficient mice for Mertk and Mfge8 (Mertk(-/-)/Mfge8(-/-)) and challenged them with acute coronary ligature. Compared with wild-type, Mertk-deficient (Mertk(-/-)), or Mfge8-deficient (Mfge8(-/-)) animals, Mertk(-/-)/Mfge8(-/-) mice displayed greater alteration in cardiac function and remodeling. Mertk and Mfge8 were expressed mainly by cardiac Ly6C(High and Low) monocytes and macrophages. In parallel, Mertk(-/-)/Mfge8(-/-) bone marrow chimeras manifested increased accumulation of apoptotic cells, enhanced fibrotic area, and larger infarct size, as well as reduced angiogenesis. We found that the abrogation of efferocytosis affected neither the ability of circulating monocytes to infiltrate cardiac tissue nor the number of resident Ly6C(High) and Ly6C(How) monocytes/macrophages populating the infarcted milieu. In contrast, combined Mertk and Mfge8 deficiency in Ly6C(High)/Ly6C(Low) monocytes/macrophages either obtained from in vitro differentiation of bone marrow cells or isolated from infarcted hearts altered their capacity of efferocytosis and subsequently blunted vascular endothelial growth factor A (VEGFA) release. Using LysMCre(+)/VEGFA(fl/fl) mice, we further identified an important role for myeloid-derived VEGFA in improving cardiac function and angiogenesis. After myocardial infarction, Mertk- and Mfge8-expressing monocyte/macrophages synergistically engage the clearance of injured cardiomyocytes, favoring the secretion of VEGFA to locally repair the dysfunctional heart. © 2016 The Authors.

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.

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

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Olofsson Jan

2008-01-01

Full Text Available Abstract Background 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. Methods 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. Results All patients, as a group, had higher in vitro monocyte responsiveness in terms of IL-6 (AS (t = 2.03; p t = 2.49; p 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 p p Conclusion 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.

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

Microparticle Shedding by Erythrocytes, Monocytes and Vascular Smooth Muscular Cells Is Reduced by Aspirin in Diabetic Patients.

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Chiva-Blanch, Gemma; Suades, Rosa; Padró, Teresa; Vilahur, Gemma; Peña, Esther; Ybarra, Juan; Pou, Jose M; Badimon, Lina

2016-07-01

Diabetes mellitus is associated with an enhanced risk for cardiovascular disease and its prevalence is increasing. Diabetes induces metabolic stress on blood and vascular cells, promoting platelet activation and vascular dysfunction. The level of vascular cell activation can be measured by the number and phenotype of microparticles found in the circulation. The aim of this study was to investigate the effect of a platelet-inhibitory dose of aspirin on the number and type of microparticles shed to the circulation. Forty-three diabetic patients were enrolled in the study and received a daily dose of 100mg of aspirin for 10 days to cover the average platelet life-span in the circulation. Before and after the intervention period, circulating microparticles were characterized and quantified by flow cytometry. Type 1 diabetic patients had about twice the number of tissue factor-positive circulating microparticles (derived both from platelets and monocytes) and endothelial-derived E-selectin positive microparticles than type 2 diabetic patients. Aspirin therapy significantly inhibited platelets since cyclooxygenase 1 derived thromboxane generation levels were reduced by 99%. Microparticles derived from erythrocytes, activated monocytes, and smooth muscle cells were significantly reduced after 10 days of aspirin administration. These results indicate that: a) vascular and blood cells in type 1 diabetic patients are exposed to more sustained stress shown by their specific microparticle origin and levels; b) aspirin therapy inhibits vascular wall cell activation and microparticle shedding, and c) the effects of aspirin are similar in type 1 and 2 diabetes. Copyright © 2016 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

An elevated serum level of endothelial monocyte activating polypeptide-II in patients with arterial hypertension with and without type 2 diabetes and obesity

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Liliya Mogylnytska

2016-07-01

Conclusions: The revealed changes could reflect an endothelial dysfunction mostly pronounced in patients with arterial hypertension, type 2 diabetes mellitus and obesity. Hyperglycemia, dyslipidemia, insulin resistance, obesity appear to be significant contributing factors leading to the elevation of EMAP-II.

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.

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

Science.gov (United States)

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.

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...

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.

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.

Exercise promotes collateral artery growth mediated by monocytic nitric oxide.

Science.gov (United States)

Schirmer, Stephan H; Millenaar, Dominic N; Werner, Christian; Schuh, Lisa; Degen, Achim; Bettink, Stephanie I; Lipp, Peter; van Rooijen, Nico; Meyer, Tim; Böhm, Michael; Laufs, Ulrich

2015-08-01

Collateral artery growth (arteriogenesis) is an important adaptive response to hampered arterial perfusion. It is unknown whether preventive physical exercise before limb ischemia can improve arteriogenesis and modulate mononuclear cell function. This study aimed at investigating the effects of endurance exercise before arterial occlusion on MNC function and collateral artery growth. After 3 weeks of voluntary treadmill exercise, ligation of the right femoral artery was performed in mice. Hindlimb perfusion immediately after surgery did not differ from sedentary mice. However, previous exercise improved perfusion restoration ≤7 days after femoral artery ligation, also when exercise was stopped at ligation. This was accompanied by an accumulation of peri-collateral macrophages and increased expression of endothelial nitric oxide synthase and inducible nitric oxide synthase (iNOS) in hindlimb collateral and in MNC of blood and spleen. Systemic monocyte and macrophage depletion by liposomal clodronate but not splenectomy attenuated exercise-induced perfusion restoration, collateral artery growth, peri-collateral macrophage accumulation, and upregulation of iNOS. iNOS-deficient mice did not show exercise-induced perfusion restoration. Transplantation of bone marrow-derived MNC from iNOS-deficient mice into wild-type animals inhibited exercise-induced collateral artery growth. In contrast to sedentary controls, thrice weekly aerobic exercise training for 6 months in humans increased peripheral blood MNC iNOS expression. Circulating mononuclear cell-derived inducible nitric oxide is an important mediator of exercise-induced collateral artery growth. © 2015 American Heart Association, Inc.

Puerarin activates endothelial nitric oxide synthase through estrogen receptor-dependent PI3-kinase and calcium-dependent AMP-activated protein kinase

International Nuclear Information System (INIS)

Hwang, Yong Pil; Kim, Hyung Gyun; Hien, Tran Thi; Jeong, Myung Ho; Jeong, Tae Cheon; Jeong, Hye Gwang

2011-01-01

The cardioprotective properties of puerarin, a natural product, have been attributed to the endothelial nitric oxide synthase (eNOS)-mediated production of nitric oxide (NO) in EA.hy926 endothelial cells. However, the mechanism by which puerarin activates eNOS remains unclear. In this study, we sought to identify the intracellular pathways underlying eNOS activation by puerarin. Puerarin induced the activating phosphorylation of eNOS on Ser1177 and the production of NO in EA.hy926 cells. Puerarin-induced eNOS phosphorylation required estrogen receptor (ER)-mediated phosphatidylinositol 3-kinase (PI3K)/Akt signaling and was reversed by AMP-activated protein kinase (AMPK) and calcium/calmodulin-dependent kinase II (CaMKII) inhibition. Importantly, puerarin inhibited the adhesion of tumor necrosis factor (TNF)-α-stimulated monocytes to endothelial cells and suppressed the TNF-α induced expression of intercellular cell adhesion molecule-1. Puerarin also inhibited the TNF-α-induced nuclear factor-κB activation, which was attenuated by pretreatment with N G -nitro-L-arginine methyl ester, a NOS inhibitor. These results indicate that puerarin stimulates eNOS phosphorylation and NO production via activation of an estrogen receptor-mediated PI3K/Akt- and CaMKII/AMPK-dependent pathway. Puerarin may be useful for the treatment or prevention of endothelial dysfunction associated with diabetes and cardiovascular disease. -- Highlights: ► Puerarin induced the phosphorylation of eNOS and the production of NO. ► Puerarin activated eNOS through ER-dependent PI3-kinase and Ca 2+ -dependent AMPK. ► Puerarin-induced NO was involved in the inhibition of NF-kB activation. ► Puerarin may help for prevention of vascular dysfunction and diabetes.

Monocyte chemoattractant protein 1 (MCP-1) in temporal arteritis and polymyalgia rheumatica

DEFF Research Database (Denmark)

Ellingsen, T; Elling, P; Olson, A

2000-01-01

was localised to the vessel wall in patients with TA. In TA, PMR, and healthy controls MCP-1 was quantified by enzyme linked immunosorbent assay (ELISA) in plasma. RESULTS: MCP-1 was localised to the majority of mononuclear cells, some smooth muscle cells, and giant cells in the arterial biopsy specimens from...

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.

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.

The metabolism of L-arginine and its significance for the biosynthesis of endothelium-derived relaxing factor: L-glutamine inhibits the generation of L-arginine by cultured endothelial cells

International Nuclear Information System (INIS)

Sessa, W.C.; Hecker, M.; Mitchell, J.A.; Vane, J.R.

1990-01-01

The mechanism by which L-glutamine (L-Gln) inhibits the release of endothelium-derived factor from bovine aortic cultured endothelial cells was investigated. The intracellular concentration of L-arginine (L-Arg) in Arg-depleted endothelial cells was inversely related to the level of L-Gln. Removal of L-Gln from the culture medium (usually containing L-Gln at 2 mM) abolished the inhibitory effect of the culture medium on L-Arg generation. L-Gln (0.2 and 2 mM) but not D-Gln inhibited the generation of L-Arg by both Arg-depleted and nondepleted endothelial cells. L-Gln did not interfere with the uptake of L-Arg or the metabolism of L-Arg-L-Phe to L-Arg but inhibited the formation of L-Arg from L-citrulline (L-Cit), L-Cit-L-Phe, and N G -monomethyl-L-arginine. L-Gln also inhibited the conversion of L-[ 14 C]Cit to L-[ 14 C]Arg by Arg-depleted endothelial cells. However, L-Gln did not inhibit the conversion of L-argininosuccinic acid to L-Arg by endothelial cell homogenates. Thus, L-Gln interferes with the conversion of L-Cit to L-Arg probably by acting on argininosuccinate synthetase rather than argininosuccinate lyase. L-Gln also inhibited the generation of L-Arg by the monocyte-macrophage cell line J774 but had no effect on the conversion of L-Cit to L-Arg by these cells. As the release of endothelium-derived relaxing factor from cultured and non-cultured endothelial cells is limited by the availability of L-Arg, endogenous L-Gln may play a regulatory role in the biosynthesis of endothelium-derived relaxing factor

Human endothelial precursor cells express tumor endothelial marker 1/endosialin/CD248.

Science.gov (United States)

Bagley, Rebecca G; Rouleau, Cecile; St Martin, Thia; Boutin, Paula; Weber, William; Ruzek, Melanie; Honma, Nakayuki; Nacht, Mariana; Shankara, Srinivas; Kataoka, Shiro; Ishida, Isao; Roberts, Bruce L; Teicher, Beverly A

2008-08-01

Angiogenesis occurs during normal physiologic processes as well as under pathologic conditions such as tumor growth. Serial analysis of gene expression profiling revealed genes [tumor endothelial markers (TEM)] that are overexpressed in tumor endothelial cells compared with normal adult endothelial cells. Because blood vessel development of malignant tumors under certain conditions may include endothelial precursor cells (EPC) recruited from bone marrow, we investigated TEM expression in EPC. The expression of TEM1 or endosialin (CD248) and other TEM has been discovered in a population of vascular endothelial growth factor receptor 2+/CD31+/CD45-/VE-cadherin+ EPC derived from human CD133+/CD34+ cells. EPC share some properties with fully differentiated endothelial cells from normal tissue, yet reverse transcription-PCR and flow cytometry reveal that EPC express higher levels of endosialin at the molecular and protein levels. The elevated expression of endosialin in EPC versus mature endothelial cells suggests that endosialin is involved in the earlier stages of tumor angiogenesis. Anti-endosialin antibodies inhibited EPC migration and tube formation in vitro. In vivo, immunohistochemistry indicated that human EPC continued to express endosialin protein in a Matrigel plug angiogenesis assay established in nude mice. Anti-endosialin antibodies delivered systemically at 25 mg/kg were also able to inhibit circulating murine EPC in nude mice bearing s.c. SKNAS tumors. EPC and bone marrow-derived cells have been shown previously to incorporate into malignant blood vessels in some instances, yet they remain controversial in the field. The data presented here on endothelial genes that are up-regulated in tumor vasculature and in EPC support the hypothesis that the angiogenesis process in cancer can involve EPC.

Human endothelial progenitor cells internalize high-density lipoprotein.

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Kaemisa Srisen

Full Text Available Endothelial progenitor cells (EPCs originate either directly from hematopoietic stem cells or from a subpopulation of monocytes. Controversial views about intracellular lipid traffic prompted us to analyze the uptake of human high density lipoprotein (HDL, and HDL-cholesterol in human monocytic EPCs. Fluorescence and electron microscopy were used to investigate distribution and intracellular trafficking of HDL and its associated cholesterol using fluorescent surrogates (bodipy-cholesterol and bodipy-cholesteryl oleate, cytochemical labels and fluorochromes including horseradish peroxidase and Alexa Fluor® 568. Uptake and intracellular transport of HDL were demonstrated after internalization periods from 0.5 to 4 hours. In case of HDL-Alexa Fluor® 568, bodipy-cholesterol and bodipy-cholesteryl oleate, a photooxidation method was carried out. HDL-specific reaction products were present in invaginations of the plasma membrane at each time of treatment within endocytic vesicles, in multivesicular bodies and at longer periods of uptake, also in lysosomes. Some HDL-positive endosomes were arranged in form of "strings of pearl"- like structures. HDL-positive multivesicular bodies exhibited intensive staining of limiting and vesicular membranes. Multivesicular bodies of HDL-Alexa Fluor® 568-treated EPCs showed multilamellar intra-vacuolar membranes. At all periods of treatment, labeled endocytic vesicles and organelles were apparent close to the cell surface and in perinuclear areas around the Golgi apparatus. No HDL-related particles could be demonstrated close to its cisterns. Electron tomographic reconstructions showed an accumulation of HDL-containing endosomes close to the trans-Golgi-network. HDL-derived bodipy-cholesterol was localized in endosomal vesicles, multivesicular bodies, lysosomes and in many of the stacked Golgi cisternae and the trans-Golgi-network Internalized HDL-derived bodipy-cholesteryl oleate was channeled into the lysosomal

A real time chemotaxis assay unveils unique migratory profiles amongst different primary murine macrophages.

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Asif J Iqbal

Full Text Available Chemotaxis assays are an invaluable tool for studying the biological activity of inflammatory mediators such as CC chemokines, which have been implicated in a wide range of chronic inflammatory diseases. Conventional chemotaxis systems such as the modified Boyden chamber are limited in terms of the data captured given that the assays are analysed at a single time-point. We report the optimisation and validation of a label-free, real-time cell migration assay based on electrical cell impedance to measure chemotaxis of different primary murine macrophage populations in response to a range of CC chemokines and other chemoattractant signalling molecules. We clearly demonstrate key differences in the migratory behavior of different murine macrophage populations and show that this dynamic system measures true macrophage chemotaxis rather than chemokinesis or fugetaxis. We highlight an absolute requirement for Gαi signaling and actin cytoskeletal rearrangement as demonstrated by Pertussis toxin and cytochalasin D inhibition. We also studied the chemotaxis of CD14(+ human monocytes and demonstrate distinct chemotactic profiles amongst different monocyte donors to CCL2. This real-time chemotaxis assay will allow a detailed analysis of factors that regulate macrophage responses to chemoattractant cytokines and inflammatory mediators.

A Real Time Chemotaxis Assay Unveils Unique Migratory Profiles amongst Different Primary Murine Macrophages

Science.gov (United States)

Iqbal, Asif J.; Regan-Komito, Daniel; Christou, Ivy; White, Gemma E.; McNeill, Eileen; Kenyon, Amy; Taylor, Lewis; Kapellos, Theodore S.; Fisher, Edward A.; Channon, Keith M.; Greaves, David R.

2013-01-01

Chemotaxis assays are an invaluable tool for studying the biological activity of inflammatory mediators such as CC chemokines, which have been implicated in a wide range of chronic inflammatory diseases. Conventional chemotaxis systems such as the modified Boyden chamber are limited in terms of the data captured given that the assays are analysed at a single time-point. We report the optimisation and validation of a label-free, real-time cell migration assay based on electrical cell impedance to measure chemotaxis of different primary murine macrophage populations in response to a range of CC chemokines and other chemoattractant signalling molecules. We clearly demonstrate key differences in the migratory behavior of different murine macrophage populations and show that this dynamic system measures true macrophage chemotaxis rather than chemokinesis or fugetaxis. We highlight an absolute requirement for Gαi signaling and actin cytoskeletal rearrangement as demonstrated by Pertussis toxin and cytochalasin D inhibition. We also studied the chemotaxis of CD14+ human monocytes and demonstrate distinct chemotactic profiles amongst different monocyte donors to CCL2. This real-time chemotaxis assay will allow a detailed analysis of factors that regulate macrophage responses to chemoattractant cytokines and inflammatory mediators. PMID:23516549

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

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....

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

Science.gov (United States)

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.

Immune-Mediated Inflammation Promotes Subclinical Atherosclerosis in Recent-Onset Psoriatic Arthritis Patients without Conventional Cardiovascular Risk Factors

Directory of Open Access Journals (Sweden)

Rodolfo A. Kolliker Frers

2018-02-01

Full Text Available Studies on the inflammatory burden in recent-onset psoriatic arthritis (PsA patients without conventional cardiovascular risk factors (CVRFs are not available. This preliminary study focuses on cardiovascular risk in cutaneous psoriasis (CPs and recent-onset PsA patients. Blood biochemistry (glucose, cholesterol, uric acid, lipid profile and apolipoprotein B was analyzed using standard kits. Proatherogenic inflammation markers, C-reactive protein (CRP and interleukin-6 (IL-6, and endothelial activators monocyte chemoattractant protein-1 (MCP-1 and soluble intercellular adhesion molecule-1 (sICAM-1, were determined by enzyme-linked immunosorbent assay. Ultrasound images allowed measuring carotid intima–media thickness (cIMT. Our study first shows an increase in cIMT, and in serum levels of sICAM-1 and CRP in recent-onset PsA patients not presenting conventional CVRFs over the non-medicated time-period, from disease diagnosis to the beginning of pharmacological treatment, compared with healthy subjects. The outcome highlights the importance of monitoring serum level of sICAM1, CRP, and cIMT, and the value of primary prevention in psoriatic patients even with no history of cardiovascular events.

Subfractions of enamel matrix derivative differentially influence cytokine secretion from human oral fibroblasts

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Oscar Villa

2015-03-01

Full Text Available Enamel matrix derivative is used to promote periodontal regeneration during the corrective phase of the treatment of periodontal defects. Our main goal was to analyze the bioactivity of different molecular weight fractions of enamel matrix derivative. Enamel matrix derivative, a complex mixture of proteins, was separated into 13 fractions using size-exclusion chromatography and characterized by sodium dodecyl sulfate–polyacrylamide gel electrophoresis and liquid chromatography–electrospray ionization–tandem mass spectrometry. Human periodontal ligament fibroblasts were treated with either enamel matrix derivative or the different fractions. Proliferation and cytokine secretion to the cell culture medium were measured and compared to untreated cells. The liquid chromatography–electrospray ionization–tandem mass spectrometry analyses revealed that the most abundant peptides were amelogenin and leucine-rich amelogenin peptide related. The fractions containing proteins above 20 kDa induced an increase in vascular endothelial growth factor and interleukin-6 secretion, whereas lower molecular weight fractions enhanced proliferation and secretion of interleukin-8 and monocyte chemoattractant protein-1 and reduced interleukin-4 release. The various molecular components in the enamel matrix derivative formulation might contribute to reported effects on tissue regeneration through their influence on vascularization, the immune response, and chemotaxis.

MCPIP1-induced autophagy mediates ischemia/reperfusion injury in endothelial cells via HMGB1 and CaSR.

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Xie, Xiaolong; Zhu, Tiebing; Chen, Lulu; Ding, Shuang; Chu, Han; Wang, Jing; Yao, Honghong; Chao, Jie

2018-01-29

Monocyte chemotactic protein-1-induced protein 1 (MCPIP1) plays a important role in ischemia/reperfusion (I/R) injury. Autophagy is involved in activating endothelial cells in response to I/R. However, researchers have not clearly determined whether MCPIP1 mediates I/R injury in endothelial cells via autophagy, and its downstream mechanism remains unclear. Western blotting analyses and immunocytochemistry were applied to detect protein levels were detected in HUVECs. An in vitro scratch assay was used to detect cell migration. Cells were transfected with siRNAs to knockdown MCPIP1 and high mobility group box 1 (HMGB1) expression. The pharmacological activator of autophagy rapamycin and the specific calcium-sensing receptor (CaSR) inhibitor NPS-2143 were used to confirm the roles of autophagy and CaSR in I/R injury. I/R induced HMGB1 and CaSR expression, which subsequently upreguated the migration and apoptosis of HUVECs and coincided with the increase of autophagy. HMGB1 was involved in cell migration, whereas CaSR specifically participated in I/R-induced HUVEC apoptosis. Based on these findings, I/R-induced MCPIP1 expression regulates the migration and apoptosis of HUVECs via HMGB1 and CaSR, respectively, suggesting a new therapeutic targetof I/R injury.

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.

Increased expression of fibronectin isoforms after myocardial infarction in rats

NARCIS (Netherlands)

Ulrich, M. M.; Janssen, A. M.; Daemen, M. J.; Rappaport, L.; Samuel, J. L.; Contard, F.; Smits, J. F.; Cleutjens, J. P.

1997-01-01

Fibronectin is a known chemoattractant for several cell types which play a role in the wound healing process, like fibroblasts, endothelial cells and macrophages. In addition, fibronectin generates a scaffold to which other extracellular matrix components can attach. The possible involvement of

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

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

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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.

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.

Outer membrane vesicles from Brucella abortus promote bacterial internalization by human monocytes and modulate their innate immune response.

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Cora N Pollak

Full Text Available Outer membrane vesicles (OMVs released by some gram-negative bacteria have been shown to exert immunomodulatory effects that favor the establishment of the infection. The aim of the present study was to assess the interaction of OMVs from Brucella abortus with human epithelial cells (HeLa and monocytes (THP-1, and the potential immunomodulatory effects they may exert. Using confocal microscopy and flow cytometry, FITC-labeled OMVs were shown to be internalized by both cell types. Internalization was shown to be partially mediated by clathrin-mediated endocytosis. Pretreatment of THP-1 cells with Brucella OMVs inhibited some cytokine responses (TNF-α and IL-8 to E. coli LPS, Pam3Cys or flagellin (TLR4, TLR2 and TLR5 agonists, respectively. Similarly, pretreatment with Brucella OMVs inhibited the cytokine response of THP-1 cells to B. abortus infection. Treatment of THP-1 cells with OMVs during IFN-γ stimulation reduced significantly the inducing effect of this cytokine on MHC-II expression. OMVs induced a dose-dependent increase of ICAM-1 expression on THP-1 cells and an increased adhesion of these cells to human endothelial cells. The addition of OMVs to THP-1 cultures before the incubation with live B. abortus resulted in increased numbers of adhered and internalized bacteria as compared to cells not treated with OMVs. Overall, these results suggest that OMVs from B. abortus exert cellular effects that promote the internalization of these bacteria by human monocytes, but also downregulate the innate immune response of these cells to Brucella infection. These effects may favor the persistence of Brucella within host cells.

The endothelial αENaC contributes to vascular endothelial function in vivo

DEFF Research Database (Denmark)

Tarjus, Antoine; Maase, Martina; Jeggle, Pia

2017-01-01

The Epithelial Sodium Channel (ENaC) is a key player in renal sodium homeostasis. The expression of α β γ ENaC subunits has also been described in the endothelium and vascular smooth muscle, suggesting a role in vascular function. We recently demonstrated that endothelial ENaC is involved in aldo......-mediated dilation. Our data suggest that endothelial αENaC contributes to vascular endothelial function in vivo....

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...

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...

Impact of MCP-1 and CCR-2 gene polymorphisms on coronary artery disease susceptibility.

Science.gov (United States)

Lin, Hsiu-Ling; Ueng, Kwo-Chang; Hsieh, Yih-Shou; Chiang, Whei-Ling; Yang, Shun-Fa; Chu, Shu-Chen

2012-09-01

Coronary artery disease (CAD) was the second leading cause of death during the last 3 years in Taiwan. Smooth muscle cells, monocytes/macrophages, and endothelial cells produce monocyte chemoattractant protein-1 (MCP-1) within atherosclerotic plaques following binding to the chemokine receptor-2 (CCR-2). Previous studies have well-documented the association between MCP-1 expression and susceptibility to, or clinicopathological features, of CAD. This study investigated the relationships between MCP-1-2518A/G and CCR-2-V64I genetic polymorphisms and CAD in the Taiwanese population. A total of 608 subjects, including 392 non-CAD controls and 216 patients with CAD, were recruited and subjected to polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) to evaluate the effects of these two polymorphic variants on CAD. Results indicated a significant association between MCP-1 -2548 gene polymorphism and susceptibility to CAD. GG genotypes (OR = 1.629; 95 % CI = 1.003-2.644), or individuals with at least one G allele (OR = 1.511; 95 % CI = 1.006-2.270), had a higher risk of CAD as compared with AA genotypes. Results also revealed that subjects with at least one A allele of the V64I CCR2 gene polymorphism had significantly increased risk of CAD. G allele in MCP-1-2518 might contribute to higher prevalence of atrial fibrillation in CAD patients (OR = 4.254; p CCR-2 64I gene polymorphisms represent important factors in determining susceptibility to CAD, and the contribution of MCP-1-2518G could be through effects on atrial fibrillation in CAD patients.

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

Catalase and superoxide dismutase conjugated with platelet-endothelial cell adhesion molecule antibody distinctly alleviate abnormal endothelial permeability caused by exogenous reactive oxygen species and vascular endothelial growth factor.

Science.gov (United States)

Han, Jingyan; Shuvaev, Vladimir V; Muzykantov, Vladimir R

2011-07-01

Reactive oxygen species (ROS) superoxide anion (O(2)()) and hydrogen peroxide (H(2)O(2)) produced by activated leukocytes and endothelial cells in sites of inflammation or ischemia cause endothelial barrier dysfunction that may lead to tissue edema. Antioxidant enzymes (AOEs) catalase and superoxide dismutase (SOD) conjugated with antibodies to platelet-endothelial cell adhesion molecule-1 (PECAM-1) specifically bind to endothelium, quench the corresponding ROS, and alleviate vascular oxidative stress and inflammation. In the present work, we studied the effects of anti-PECAM/catalase and anti-PECAM/SOD conjugates on the abnormal permeability manifested by transendothelial electrical resistance decline, increased fluorescein isothiocyanate-dextran influx, and redistribution of vascular endothelial-cadherin in human umbilical vein endothelial cell (HUVEC) monolayers. Anti-PECAM/catalase protected HUVEC monolayers against H(2)O(2)-induced endothelial barrier dysfunction. Polyethylene glycol-conjugated catalase exerted orders of magnitude lower endothelial uptake and no protective effect, similarly to IgG/catalase. Anti-PECAM/catalase, but not anti-PECAM/SOD, alleviated endothelial hyperpermeability caused by exposure to hypoxanthine/xanthine oxidase, implicating primarily H(2)O(2) in the disruption of the endothelial barrier in this model. Thrombin-induced endothelial permeability was not affected by treatment with anti-PECAM/AOEs or the NADPH oxidase inhibitor apocynin or overexpression of AOEs, indicating that the endogenous ROS play no key role in thrombin-mediated endothelial barrier dysfunction. In contrast, anti-PECAM/SOD, but not anti-PECAM/catalase, inhibited a vascular endothelial growth factor (VEGF)-induced increase in endothelial permeability, identifying a key role of endogenous O(2)() in the VEGF-mediated regulation of endothelial barrier function. Therefore, AOEs targeted to endothelial cells provide versatile molecular tools for testing the roles of

Endothelial microparticle-mediated transfer of MicroRNA-126 promotes vascular endothelial cell repair via SPRED1 and is abrogated in glucose-damaged endothelial microparticles.

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Jansen, Felix; Yang, Xiaoyan; Hoelscher, Marion; Cattelan, Arianna; Schmitz, Theresa; Proebsting, Sebastian; Wenzel, Daniela; Vosen, Sarah; Franklin, Bernardo S; Fleischmann, Bernd K; Nickenig, Georg; Werner, Nikos

2013-10-29

Repair of the endothelium after vascular injury is crucial for preserving endothelial integrity and preventing the development of vascular disease. The underlying mechanisms of endothelial cell repair are largely unknown. We sought to investigate whether endothelial microparticles (EMPs), released from apoptotic endothelial cells (ECs), influence EC repair. Systemic treatment of mice with EMPs after electric denudation of the endothelium accelerated reendothelialization in vivo. In vitro experiments revealed that EMP uptake in ECs promotes EC migration and proliferation, both critical steps in endothelial repair. To dissect the underlying mechanisms, Taqman microRNA array was performed, and microRNA (miR)-126 was identified as the predominantly expressed miR in EMPs. The following experiments demonstrated that miR-126 was transported into recipient human coronary artery endothelial cells by EMPs and functionally regulated the target protein sprouty-related, EVH1 domain-containing protein 1 (SPRED1). Knockdown of miR-126 in EMPs abrogated EMP-mediated effects on human coronary artery endothelial cell migration and proliferation in vitro and reendothelialization in vivo. Interestingly, after simulating diabetic conditions, EMPs derived from glucose-treated ECs contained significantly lower amounts of miR-126 and showed reduced endothelial repair capacity in vitro and in vivo. Finally, expression analysis of miR-126 in circulating microparticles from 176 patients with stable coronary artery disease with and without diabetes mellitus revealed a significantly reduced miR-126 expression in circulating microparticles from diabetic patients. Endothelial microparticles promote vascular endothelial repair by delivering functional miR-126 into recipient cells. In pathological hyperglycemic conditions, EMP-mediated miR-126-induced EC repair is altered.

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.

Interleukin-17A and Toll-Like Receptor 3 Ligand Poly(I:C Synergistically Induced Neutrophil Chemoattractant Production by Bronchial Epithelial Cells.

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Hirotaka Matsuzaki

Full Text Available Chronic inflammatory airway diseases, such as bronchial asthma and chronic obstructive pulmonary disease, are common respiratory disorders worldwide. Exacerbations of these diseases are frequent and worsen patients' respiratory condition and overall health. However, the mechanisms of exacerbation have not been fully elucidated. Recently, it was reported that interleukin (IL-17A might play an important role in neutrophilic inflammation, which is characteristic of such exacerbations, through increased production of neutrophil chemoattractants. Therefore, we hypothesized that IL-17A was involved in the pathogenesis of acute exacerbation, due to viral infection in chronic inflammatory airway diseases. In this study, we assessed chemokine production by bronchial epithelial cells and investigated the underlying mechanisms. Comprehensive chemokine analysis showed that, compared with poly(I:C alone, co-stimulation of BEAS-2B cells with IL-17A and poly(I:C strongly induced production of such neutrophil chemoattractants as CXC chemokine ligand (CXCL8, growth-related oncogene (GRO, and CXCL1. Co-stimulation synergistically induced CXCL8 and CXCL1 mRNA and protein production by BEAS-2B cells and normal human bronchial epithelial cells. Poly(I:C induced chemokine expression by BEAS-2B cells mainly via Toll-like receptor 3/TIR-domain-containing adapter-inducing interferon-β-mediated signals. The co-stimulation with IL-17A and poly(I:C markedly activated the p38 and extracellular-signal-regulated kinase 1/2 pathway, compared with poly(I:C, although there was little change in nuclear factor-κB translocation into the nucleus or the transcriptional activities of nuclear factor-κB and activator protein 1. IL-17A promoted stabilization of CXCL8 mRNA in BEAS-2B cells treated with poly(I:C. In conclusion, IL-17A appears to be involved in the pathogenesis of chronic inflammatory airway disease exacerbation, due to viral infection by promoting release of neutrophil

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.

Endothelial MMP14 is required for endothelial-dependent growth support of human airway basal cells

Science.gov (United States)

Ding, Bi-Sen; Gomi, Kazunori; Rafii, Shahin; Crystal, Ronald G.; Walters, Matthew S.

2015-01-01

ABSTRACT Human airway basal cells are the stem (or progenitor) population of the airway epithelium, and play a central role in anchoring the epithelium to the basement membrane. The anatomic position of basal cells allows for potential paracrine signaling between them and the underlying non-epithelial stromal cells. In support of this, we have previously demonstrated that endothelial cells support growth of basal cells during co-culture through vascular endothelial growth factor A (VEGFA)-mediated signaling. Building on these findings, we found, by RNA sequencing analysis, that basal cells expressed multiple fibroblast growth factor (FGF) ligands (FGF2, FGF5, FGF11 and FGF13) and that only FGF2 and FGF5 were capable of functioning in a paracrine manner to activate classical FGF receptor (FGFR) signaling. Antibody-mediated blocking of FGFR1 during basal-cell–endothelial-cell co-culture significantly reduced the endothelial-cell-dependent basal cell growth. Stimulation of endothelial cells with basal-cell-derived growth factors induced endothelial cell expression of matrix metallopeptidase 14 (MMP14), and short hairpin RNA (shRNA)-mediated knockdown of endothelial cell MMP14 significantly reduced the endothelial-cell-dependent growth of basal cells. Overall, these data characterize a new growth-factor-mediated reciprocal ‘crosstalk’ between human airway basal cells and endothelial cells that regulates proliferation of basal cells. PMID:26116571

Whole blood flow cytometric analysis of Ureaplasma-stimulated monocytes from pregnant women.